diff options
Diffstat (limited to 'drivers/gpu/drm/display')
| -rw-r--r-- | drivers/gpu/drm/display/Kconfig | 51 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/Makefile | 16 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_display_helper_mod.c | 22 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_aux_bus.c | 386 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_aux_dev.c | 354 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_cec.c | 451 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_dual_mode_helper.c | 537 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_helper.c | 3893 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_helper_internal.h | 33 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_mst_topology.c | 5929 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_mst_topology_internal.h | 24 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_dsc_helper.c | 409 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_hdcp_helper.c | 421 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_hdmi_helper.c | 197 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_scdc_helper.c | 263 |
15 files changed, 12986 insertions, 0 deletions
diff --git a/drivers/gpu/drm/display/Kconfig b/drivers/gpu/drm/display/Kconfig new file mode 100644 index 000000000..09712b88a --- /dev/null +++ b/drivers/gpu/drm/display/Kconfig @@ -0,0 +1,51 @@ +# SPDX-License-Identifier: MIT + +config DRM_DP_AUX_BUS + tristate + depends on DRM + depends on OF || COMPILE_TEST + +config DRM_DISPLAY_HELPER + tristate + depends on DRM + help + DRM helpers for display adapters. + +config DRM_DISPLAY_DP_HELPER + bool + depends on DRM_DISPLAY_HELPER + help + DRM display helpers for DisplayPort. + +config DRM_DISPLAY_HDCP_HELPER + bool + depends on DRM_DISPLAY_HELPER + help + DRM display helpers for HDCP. + +config DRM_DISPLAY_HDMI_HELPER + bool + depends on DRM_DISPLAY_HELPER + help + DRM display helpers for HDMI. + +config DRM_DP_AUX_CHARDEV + bool "DRM DP AUX Interface" + depends on DRM && DRM_DISPLAY_HELPER + select DRM_DISPLAY_DP_HELPER + help + Choose this option to enable a /dev/drm_dp_auxN node that allows to + read and write values to arbitrary DPCD registers on the DP aux + channel. + +config DRM_DP_CEC + bool "Enable DisplayPort CEC-Tunneling-over-AUX HDMI support" + depends on DRM && DRM_DISPLAY_HELPER + select DRM_DISPLAY_DP_HELPER + select CEC_CORE + help + Choose this option if you want to enable HDMI CEC support for + DisplayPort/USB-C to HDMI adapters. + + Note: not all adapters support this feature, and even for those + that do support this they often do not hook up the CEC pin. diff --git a/drivers/gpu/drm/display/Makefile b/drivers/gpu/drm/display/Makefile new file mode 100644 index 000000000..52cdda118 --- /dev/null +++ b/drivers/gpu/drm/display/Makefile @@ -0,0 +1,16 @@ +# SPDX-License-Identifier: MIT + +obj-$(CONFIG_DRM_DP_AUX_BUS) += drm_dp_aux_bus.o + +drm_display_helper-y := drm_display_helper_mod.o +drm_display_helper-$(CONFIG_DRM_DISPLAY_DP_HELPER) += drm_dp_dual_mode_helper.o \ + drm_dp_helper.o \ + drm_dp_mst_topology.o \ + drm_dsc_helper.o +drm_display_helper-$(CONFIG_DRM_DISPLAY_HDCP_HELPER) += drm_hdcp_helper.o +drm_display_helper-$(CONFIG_DRM_DISPLAY_HDMI_HELPER) += drm_hdmi_helper.o \ + drm_scdc_helper.o +drm_display_helper-$(CONFIG_DRM_DP_AUX_CHARDEV) += drm_dp_aux_dev.o +drm_display_helper-$(CONFIG_DRM_DP_CEC) += drm_dp_cec.o + +obj-$(CONFIG_DRM_DISPLAY_HELPER) += drm_display_helper.o diff --git a/drivers/gpu/drm/display/drm_display_helper_mod.c b/drivers/gpu/drm/display/drm_display_helper_mod.c new file mode 100644 index 000000000..d8a6e6228 --- /dev/null +++ b/drivers/gpu/drm/display/drm_display_helper_mod.c @@ -0,0 +1,22 @@ +// SPDX-License-Identifier: MIT + +#include <linux/module.h> + +#include "drm_dp_helper_internal.h" + +MODULE_DESCRIPTION("DRM display adapter helper"); +MODULE_LICENSE("GPL and additional rights"); + +static int __init drm_display_helper_module_init(void) +{ + return drm_dp_aux_dev_init(); +} + +static void __exit drm_display_helper_module_exit(void) +{ + /* Call exit functions from specific dp helpers here */ + drm_dp_aux_dev_exit(); +} + +module_init(drm_display_helper_module_init); +module_exit(drm_display_helper_module_exit); diff --git a/drivers/gpu/drm/display/drm_dp_aux_bus.c b/drivers/gpu/drm/display/drm_dp_aux_bus.c new file mode 100644 index 000000000..f5741b45c --- /dev/null +++ b/drivers/gpu/drm/display/drm_dp_aux_bus.c @@ -0,0 +1,386 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2021 Google Inc. + * + * The DP AUX bus is used for devices that are connected over a DisplayPort + * AUX bus. The device on the far side of the bus is referred to as an + * endpoint in this code. + * + * There is only one device connected to the DP AUX bus: an eDP panel. + * Though historically panels (even DP panels) have been modeled as simple + * platform devices, putting them under the DP AUX bus allows the panel driver + * to perform transactions on that bus. + */ + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/pm_domain.h> +#include <linux/pm_runtime.h> + +#include <drm/display/drm_dp_aux_bus.h> +#include <drm/display/drm_dp_helper.h> + +struct dp_aux_ep_device_with_data { + struct dp_aux_ep_device aux_ep; + int (*done_probing)(struct drm_dp_aux *aux); +}; + +/** + * dp_aux_ep_match() - The match function for the dp_aux_bus. + * @dev: The device to match. + * @drv: The driver to try to match against. + * + * At the moment, we just match on device tree. + * + * Return: True if this driver matches this device; false otherwise. + */ +static int dp_aux_ep_match(struct device *dev, struct device_driver *drv) +{ + return !!of_match_device(drv->of_match_table, dev); +} + +/** + * dp_aux_ep_probe() - The probe function for the dp_aux_bus. + * @dev: The device to probe. + * + * Calls through to the endpoint driver probe. + * + * Return: 0 if no error or negative error code. + */ +static int dp_aux_ep_probe(struct device *dev) +{ + struct dp_aux_ep_driver *aux_ep_drv = to_dp_aux_ep_drv(dev->driver); + struct dp_aux_ep_device *aux_ep = to_dp_aux_ep_dev(dev); + struct dp_aux_ep_device_with_data *aux_ep_with_data = + container_of(aux_ep, struct dp_aux_ep_device_with_data, aux_ep); + int ret; + + ret = dev_pm_domain_attach(dev, true); + if (ret) + return dev_err_probe(dev, ret, "Failed to attach to PM Domain\n"); + + ret = aux_ep_drv->probe(aux_ep); + if (ret) + goto err_attached; + + if (aux_ep_with_data->done_probing) { + ret = aux_ep_with_data->done_probing(aux_ep->aux); + if (ret) { + /* + * The done_probing() callback should not return + * -EPROBE_DEFER to us. If it does, we treat it as an + * error. Passing it on as-is would cause the _panel_ + * to defer. + */ + if (ret == -EPROBE_DEFER) { + dev_err(dev, + "DP AUX done_probing() can't defer\n"); + ret = -EINVAL; + } + goto err_probed; + } + } + + return 0; +err_probed: + if (aux_ep_drv->remove) + aux_ep_drv->remove(aux_ep); +err_attached: + dev_pm_domain_detach(dev, true); + + return ret; +} + +/** + * dp_aux_ep_remove() - The remove function for the dp_aux_bus. + * @dev: The device to remove. + * + * Calls through to the endpoint driver remove. + */ +static void dp_aux_ep_remove(struct device *dev) +{ + struct dp_aux_ep_driver *aux_ep_drv = to_dp_aux_ep_drv(dev->driver); + struct dp_aux_ep_device *aux_ep = to_dp_aux_ep_dev(dev); + + if (aux_ep_drv->remove) + aux_ep_drv->remove(aux_ep); + dev_pm_domain_detach(dev, true); +} + +/** + * dp_aux_ep_shutdown() - The shutdown function for the dp_aux_bus. + * @dev: The device to shutdown. + * + * Calls through to the endpoint driver shutdown. + */ +static void dp_aux_ep_shutdown(struct device *dev) +{ + struct dp_aux_ep_driver *aux_ep_drv; + + if (!dev->driver) + return; + + aux_ep_drv = to_dp_aux_ep_drv(dev->driver); + if (aux_ep_drv->shutdown) + aux_ep_drv->shutdown(to_dp_aux_ep_dev(dev)); +} + +static struct bus_type dp_aux_bus_type = { + .name = "dp-aux", + .match = dp_aux_ep_match, + .probe = dp_aux_ep_probe, + .remove = dp_aux_ep_remove, + .shutdown = dp_aux_ep_shutdown, +}; + +static ssize_t modalias_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return of_device_modalias(dev, buf, PAGE_SIZE); +} +static DEVICE_ATTR_RO(modalias); + +static struct attribute *dp_aux_ep_dev_attrs[] = { + &dev_attr_modalias.attr, + NULL, +}; +ATTRIBUTE_GROUPS(dp_aux_ep_dev); + +/** + * dp_aux_ep_dev_release() - Free memory for the dp_aux_ep device + * @dev: The device to free. + */ +static void dp_aux_ep_dev_release(struct device *dev) +{ + struct dp_aux_ep_device *aux_ep = to_dp_aux_ep_dev(dev); + struct dp_aux_ep_device_with_data *aux_ep_with_data = + container_of(aux_ep, struct dp_aux_ep_device_with_data, aux_ep); + + kfree(aux_ep_with_data); +} + +static struct device_type dp_aux_device_type_type = { + .groups = dp_aux_ep_dev_groups, + .uevent = of_device_uevent_modalias, + .release = dp_aux_ep_dev_release, +}; + +/** + * of_dp_aux_ep_destroy() - Destroy an DP AUX endpoint device + * @dev: The device to destroy. + * @data: Not used + * + * This is just used as a callback by of_dp_aux_depopulate_bus() and + * is called for _all_ of the child devices of the device providing the AUX bus. + * We'll only act on those that are of type "dp_aux_bus_type". + * + * This function is effectively an inverse of what's in + * of_dp_aux_populate_bus(). NOTE: since we only populate one child + * then it's expected that only one device will match all the "if" tests in + * this function and get to the device_unregister(). + * + * Return: 0 if no error or negative error code. + */ +static int of_dp_aux_ep_destroy(struct device *dev, void *data) +{ + struct device_node *np = dev->of_node; + + if (dev->bus != &dp_aux_bus_type) + return 0; + + if (!of_node_check_flag(np, OF_POPULATED)) + return 0; + + of_node_clear_flag(np, OF_POPULATED); + of_node_put(np); + + device_unregister(dev); + + return 0; +} + +/** + * of_dp_aux_depopulate_bus() - Undo of_dp_aux_populate_bus + * @aux: The AUX channel whose device we want to depopulate + * + * This will destroy the device that was created + * by of_dp_aux_populate_bus(). + */ +void of_dp_aux_depopulate_bus(struct drm_dp_aux *aux) +{ + device_for_each_child_reverse(aux->dev, NULL, of_dp_aux_ep_destroy); +} +EXPORT_SYMBOL_GPL(of_dp_aux_depopulate_bus); + +/** + * of_dp_aux_populate_bus() - Populate the endpoint device on the DP AUX + * @aux: The AUX channel whose device we want to populate. It is required that + * drm_dp_aux_init() has already been called for this AUX channel. + * @done_probing: Callback functions to call after EP device finishes probing. + * Will not be called if there are no EP devices and this + * function will return -ENODEV. + * + * This will populate the device (expected to be an eDP panel) under the + * "aux-bus" node of the device providing the AUX channel (AKA aux->dev). + * + * When this function finishes, it is _possible_ (but not guaranteed) that + * our sub-device will have finished probing. It should be noted that if our + * sub-device returns -EPROBE_DEFER or is probing asynchronously for some + * reason that we will not return any error codes ourselves but our + * sub-device will _not_ have actually probed successfully yet. + * + * In many cases it's important for the caller of this function to be notified + * when our sub device finishes probing. Our sub device is expected to be an + * eDP panel and the caller is expected to be an eDP controller. The eDP + * controller needs to be able to get a reference to the panel when it finishes + * probing. For this reason the caller can pass in a function pointer that + * will be called when our sub-device finishes probing. + * + * If this function succeeds you should later make sure you call + * of_dp_aux_depopulate_bus() to undo it, or just use the devm version + * of this function. + * + * Return: 0 if no error or negative error code; returns -ENODEV if there are + * no children. The done_probing() function won't be called in that + * case. + */ +int of_dp_aux_populate_bus(struct drm_dp_aux *aux, + int (*done_probing)(struct drm_dp_aux *aux)) +{ + struct device_node *bus = NULL, *np = NULL; + struct dp_aux_ep_device *aux_ep; + struct dp_aux_ep_device_with_data *aux_ep_with_data; + int ret; + + /* drm_dp_aux_init() should have been called already; warn if not */ + WARN_ON_ONCE(!aux->ddc.algo); + + if (!aux->dev->of_node) + return -ENODEV; + bus = of_get_child_by_name(aux->dev->of_node, "aux-bus"); + if (!bus) + return -ENODEV; + + np = of_get_next_available_child(bus, NULL); + of_node_put(bus); + if (!np) + return -ENODEV; + + if (of_node_test_and_set_flag(np, OF_POPULATED)) { + dev_err(aux->dev, "DP AUX EP device already populated\n"); + ret = -EINVAL; + goto err_did_get_np; + } + + aux_ep_with_data = kzalloc(sizeof(*aux_ep_with_data), GFP_KERNEL); + if (!aux_ep_with_data) { + ret = -ENOMEM; + goto err_did_set_populated; + } + + aux_ep_with_data->done_probing = done_probing; + + aux_ep = &aux_ep_with_data->aux_ep; + aux_ep->aux = aux; + aux_ep->dev.parent = aux->dev; + aux_ep->dev.bus = &dp_aux_bus_type; + aux_ep->dev.type = &dp_aux_device_type_type; + aux_ep->dev.of_node = of_node_get(np); + dev_set_name(&aux_ep->dev, "aux-%s", dev_name(aux->dev)); + + ret = device_register(&aux_ep->dev); + if (ret) { + dev_err(aux->dev, "Failed to create AUX EP for %pOF: %d\n", np, ret); + + /* + * As per docs of device_register(), call this instead + * of kfree() directly for error cases. + */ + put_device(&aux_ep->dev); + + goto err_did_set_populated; + } + + return 0; + +err_did_set_populated: + of_node_clear_flag(np, OF_POPULATED); + +err_did_get_np: + of_node_put(np); + + return ret; +} +EXPORT_SYMBOL_GPL(of_dp_aux_populate_bus); + +static void of_dp_aux_depopulate_bus_void(void *data) +{ + of_dp_aux_depopulate_bus(data); +} + +/** + * devm_of_dp_aux_populate_bus() - devm wrapper for of_dp_aux_populate_bus() + * @aux: The AUX channel whose device we want to populate + * @done_probing: Callback functions to call after EP device finishes probing. + * Will not be called if there are no EP devices and this + * function will return -ENODEV. + * + * Handles freeing w/ devm on the device "aux->dev". + * + * Return: 0 if no error or negative error code; returns -ENODEV if there are + * no children. The done_probing() function won't be called in that + * case. + */ +int devm_of_dp_aux_populate_bus(struct drm_dp_aux *aux, + int (*done_probing)(struct drm_dp_aux *aux)) +{ + int ret; + + ret = of_dp_aux_populate_bus(aux, done_probing); + if (ret) + return ret; + + return devm_add_action_or_reset(aux->dev, + of_dp_aux_depopulate_bus_void, aux); +} +EXPORT_SYMBOL_GPL(devm_of_dp_aux_populate_bus); + +int __dp_aux_dp_driver_register(struct dp_aux_ep_driver *drv, struct module *owner) +{ + drv->driver.owner = owner; + drv->driver.bus = &dp_aux_bus_type; + + return driver_register(&drv->driver); +} +EXPORT_SYMBOL_GPL(__dp_aux_dp_driver_register); + +void dp_aux_dp_driver_unregister(struct dp_aux_ep_driver *drv) +{ + driver_unregister(&drv->driver); +} +EXPORT_SYMBOL_GPL(dp_aux_dp_driver_unregister); + +static int __init dp_aux_bus_init(void) +{ + int ret; + + ret = bus_register(&dp_aux_bus_type); + if (ret) + return ret; + + return 0; +} + +static void __exit dp_aux_bus_exit(void) +{ + bus_unregister(&dp_aux_bus_type); +} + +subsys_initcall(dp_aux_bus_init); +module_exit(dp_aux_bus_exit); + +MODULE_AUTHOR("Douglas Anderson <dianders@chromium.org>"); +MODULE_DESCRIPTION("DRM DisplayPort AUX bus"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/gpu/drm/display/drm_dp_aux_dev.c b/drivers/gpu/drm/display/drm_dp_aux_dev.c new file mode 100644 index 000000000..098e482e6 --- /dev/null +++ b/drivers/gpu/drm/display/drm_dp_aux_dev.c @@ -0,0 +1,354 @@ +/* + * Copyright © 2015 Intel Corporation + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + * + * Authors: + * Rafael Antognolli <rafael.antognolli@intel.com> + * + */ + +#include <linux/device.h> +#include <linux/fs.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/sched/signal.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <linux/uio.h> + +#include <drm/display/drm_dp_helper.h> +#include <drm/display/drm_dp_mst_helper.h> +#include <drm/drm_crtc.h> +#include <drm/drm_print.h> + +#include "drm_dp_helper_internal.h" + +struct drm_dp_aux_dev { + unsigned index; + struct drm_dp_aux *aux; + struct device *dev; + struct kref refcount; + atomic_t usecount; +}; + +#define DRM_AUX_MINORS 256 +#define AUX_MAX_OFFSET (1 << 20) +static DEFINE_IDR(aux_idr); +static DEFINE_MUTEX(aux_idr_mutex); +static struct class *drm_dp_aux_dev_class; +static int drm_dev_major = -1; + +static struct drm_dp_aux_dev *drm_dp_aux_dev_get_by_minor(unsigned index) +{ + struct drm_dp_aux_dev *aux_dev = NULL; + + mutex_lock(&aux_idr_mutex); + aux_dev = idr_find(&aux_idr, index); + if (aux_dev && !kref_get_unless_zero(&aux_dev->refcount)) + aux_dev = NULL; + mutex_unlock(&aux_idr_mutex); + + return aux_dev; +} + +static struct drm_dp_aux_dev *alloc_drm_dp_aux_dev(struct drm_dp_aux *aux) +{ + struct drm_dp_aux_dev *aux_dev; + int index; + + aux_dev = kzalloc(sizeof(*aux_dev), GFP_KERNEL); + if (!aux_dev) + return ERR_PTR(-ENOMEM); + aux_dev->aux = aux; + atomic_set(&aux_dev->usecount, 1); + kref_init(&aux_dev->refcount); + + mutex_lock(&aux_idr_mutex); + index = idr_alloc(&aux_idr, aux_dev, 0, DRM_AUX_MINORS, GFP_KERNEL); + mutex_unlock(&aux_idr_mutex); + if (index < 0) { + kfree(aux_dev); + return ERR_PTR(index); + } + aux_dev->index = index; + + return aux_dev; +} + +static void release_drm_dp_aux_dev(struct kref *ref) +{ + struct drm_dp_aux_dev *aux_dev = + container_of(ref, struct drm_dp_aux_dev, refcount); + + kfree(aux_dev); +} + +static ssize_t name_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + ssize_t res; + struct drm_dp_aux_dev *aux_dev = + drm_dp_aux_dev_get_by_minor(MINOR(dev->devt)); + + if (!aux_dev) + return -ENODEV; + + res = sprintf(buf, "%s\n", aux_dev->aux->name); + kref_put(&aux_dev->refcount, release_drm_dp_aux_dev); + + return res; +} +static DEVICE_ATTR_RO(name); + +static struct attribute *drm_dp_aux_attrs[] = { + &dev_attr_name.attr, + NULL, +}; +ATTRIBUTE_GROUPS(drm_dp_aux); + +static int auxdev_open(struct inode *inode, struct file *file) +{ + unsigned int minor = iminor(inode); + struct drm_dp_aux_dev *aux_dev; + + aux_dev = drm_dp_aux_dev_get_by_minor(minor); + if (!aux_dev) + return -ENODEV; + + file->private_data = aux_dev; + return 0; +} + +static loff_t auxdev_llseek(struct file *file, loff_t offset, int whence) +{ + return fixed_size_llseek(file, offset, whence, AUX_MAX_OFFSET); +} + +static ssize_t auxdev_read_iter(struct kiocb *iocb, struct iov_iter *to) +{ + struct drm_dp_aux_dev *aux_dev = iocb->ki_filp->private_data; + loff_t pos = iocb->ki_pos; + ssize_t res = 0; + + if (!atomic_inc_not_zero(&aux_dev->usecount)) + return -ENODEV; + + iov_iter_truncate(to, AUX_MAX_OFFSET - pos); + + while (iov_iter_count(to)) { + uint8_t buf[DP_AUX_MAX_PAYLOAD_BYTES]; + ssize_t todo = min(iov_iter_count(to), sizeof(buf)); + + if (signal_pending(current)) { + res = -ERESTARTSYS; + break; + } + + res = drm_dp_dpcd_read(aux_dev->aux, pos, buf, todo); + + if (res <= 0) + break; + + if (copy_to_iter(buf, res, to) != res) { + res = -EFAULT; + break; + } + + pos += res; + } + + if (pos != iocb->ki_pos) + res = pos - iocb->ki_pos; + iocb->ki_pos = pos; + + if (atomic_dec_and_test(&aux_dev->usecount)) + wake_up_var(&aux_dev->usecount); + + return res; +} + +static ssize_t auxdev_write_iter(struct kiocb *iocb, struct iov_iter *from) +{ + struct drm_dp_aux_dev *aux_dev = iocb->ki_filp->private_data; + loff_t pos = iocb->ki_pos; + ssize_t res = 0; + + if (!atomic_inc_not_zero(&aux_dev->usecount)) + return -ENODEV; + + iov_iter_truncate(from, AUX_MAX_OFFSET - pos); + + while (iov_iter_count(from)) { + uint8_t buf[DP_AUX_MAX_PAYLOAD_BYTES]; + ssize_t todo = min(iov_iter_count(from), sizeof(buf)); + + if (signal_pending(current)) { + res = -ERESTARTSYS; + break; + } + + if (!copy_from_iter_full(buf, todo, from)) { + res = -EFAULT; + break; + } + + res = drm_dp_dpcd_write(aux_dev->aux, pos, buf, todo); + + if (res <= 0) + break; + + pos += res; + } + + if (pos != iocb->ki_pos) + res = pos - iocb->ki_pos; + iocb->ki_pos = pos; + + if (atomic_dec_and_test(&aux_dev->usecount)) + wake_up_var(&aux_dev->usecount); + + return res; +} + +static int auxdev_release(struct inode *inode, struct file *file) +{ + struct drm_dp_aux_dev *aux_dev = file->private_data; + + kref_put(&aux_dev->refcount, release_drm_dp_aux_dev); + return 0; +} + +static const struct file_operations auxdev_fops = { + .owner = THIS_MODULE, + .llseek = auxdev_llseek, + .read_iter = auxdev_read_iter, + .write_iter = auxdev_write_iter, + .open = auxdev_open, + .release = auxdev_release, +}; + +#define to_auxdev(d) container_of(d, struct drm_dp_aux_dev, aux) + +static struct drm_dp_aux_dev *drm_dp_aux_dev_get_by_aux(struct drm_dp_aux *aux) +{ + struct drm_dp_aux_dev *iter, *aux_dev = NULL; + int id; + + /* don't increase kref count here because this function should only be + * used by drm_dp_aux_unregister_devnode. Thus, it will always have at + * least one reference - the one that drm_dp_aux_register_devnode + * created + */ + mutex_lock(&aux_idr_mutex); + idr_for_each_entry(&aux_idr, iter, id) { + if (iter->aux == aux) { + aux_dev = iter; + break; + } + } + mutex_unlock(&aux_idr_mutex); + return aux_dev; +} + +void drm_dp_aux_unregister_devnode(struct drm_dp_aux *aux) +{ + struct drm_dp_aux_dev *aux_dev; + unsigned int minor; + + aux_dev = drm_dp_aux_dev_get_by_aux(aux); + if (!aux_dev) /* attach must have failed */ + return; + + /* + * As some AUX adapters may exist as platform devices which outlive their respective DRM + * devices, we clear drm_dev to ensure that we never accidentally reference a stale pointer + */ + aux->drm_dev = NULL; + + mutex_lock(&aux_idr_mutex); + idr_remove(&aux_idr, aux_dev->index); + mutex_unlock(&aux_idr_mutex); + + atomic_dec(&aux_dev->usecount); + wait_var_event(&aux_dev->usecount, !atomic_read(&aux_dev->usecount)); + + minor = aux_dev->index; + if (aux_dev->dev) + device_destroy(drm_dp_aux_dev_class, + MKDEV(drm_dev_major, minor)); + + DRM_DEBUG("drm_dp_aux_dev: aux [%s] unregistering\n", aux->name); + kref_put(&aux_dev->refcount, release_drm_dp_aux_dev); +} + +int drm_dp_aux_register_devnode(struct drm_dp_aux *aux) +{ + struct drm_dp_aux_dev *aux_dev; + int res; + + aux_dev = alloc_drm_dp_aux_dev(aux); + if (IS_ERR(aux_dev)) + return PTR_ERR(aux_dev); + + aux_dev->dev = device_create(drm_dp_aux_dev_class, aux->dev, + MKDEV(drm_dev_major, aux_dev->index), NULL, + "drm_dp_aux%d", aux_dev->index); + if (IS_ERR(aux_dev->dev)) { + res = PTR_ERR(aux_dev->dev); + aux_dev->dev = NULL; + goto error; + } + + DRM_DEBUG("drm_dp_aux_dev: aux [%s] registered as minor %d\n", + aux->name, aux_dev->index); + return 0; +error: + drm_dp_aux_unregister_devnode(aux); + return res; +} + +int drm_dp_aux_dev_init(void) +{ + int res; + + drm_dp_aux_dev_class = class_create(THIS_MODULE, "drm_dp_aux_dev"); + if (IS_ERR(drm_dp_aux_dev_class)) { + return PTR_ERR(drm_dp_aux_dev_class); + } + drm_dp_aux_dev_class->dev_groups = drm_dp_aux_groups; + + res = register_chrdev(0, "aux", &auxdev_fops); + if (res < 0) + goto out; + drm_dev_major = res; + + return 0; +out: + class_destroy(drm_dp_aux_dev_class); + return res; +} + +void drm_dp_aux_dev_exit(void) +{ + unregister_chrdev(drm_dev_major, "aux"); + class_destroy(drm_dp_aux_dev_class); +} diff --git a/drivers/gpu/drm/display/drm_dp_cec.c b/drivers/gpu/drm/display/drm_dp_cec.c new file mode 100644 index 000000000..ae39dc794 --- /dev/null +++ b/drivers/gpu/drm/display/drm_dp_cec.c @@ -0,0 +1,451 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DisplayPort CEC-Tunneling-over-AUX support + * + * Copyright 2018 Cisco Systems, Inc. and/or its affiliates. All rights reserved. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> + +#include <media/cec.h> + +#include <drm/display/drm_dp_helper.h> +#include <drm/drm_connector.h> +#include <drm/drm_device.h> + +/* + * Unfortunately it turns out that we have a chicken-and-egg situation + * here. Quite a few active (mini-)DP-to-HDMI or USB-C-to-HDMI adapters + * have a converter chip that supports CEC-Tunneling-over-AUX (usually the + * Parade PS176), but they do not wire up the CEC pin, thus making CEC + * useless. Note that MegaChips 2900-based adapters appear to have good + * support for CEC tunneling. Those adapters that I have tested using + * this chipset all have the CEC line connected. + * + * Sadly there is no way for this driver to know this. What happens is + * that a /dev/cecX device is created that is isolated and unable to see + * any of the other CEC devices. Quite literally the CEC wire is cut + * (or in this case, never connected in the first place). + * + * The reason so few adapters support this is that this tunneling protocol + * was never supported by any OS. So there was no easy way of testing it, + * and no incentive to correctly wire up the CEC pin. + * + * Hopefully by creating this driver it will be easier for vendors to + * finally fix their adapters and test the CEC functionality. + * + * I keep a list of known working adapters here: + * + * https://hverkuil.home.xs4all.nl/cec-status.txt + * + * Please mail me (hverkuil@xs4all.nl) if you find an adapter that works + * and is not yet listed there. + * + * Note that the current implementation does not support CEC over an MST hub. + * As far as I can see there is no mechanism defined in the DisplayPort + * standard to transport CEC interrupts over an MST device. It might be + * possible to do this through polling, but I have not been able to get that + * to work. + */ + +/** + * DOC: dp cec helpers + * + * These functions take care of supporting the CEC-Tunneling-over-AUX + * feature of DisplayPort-to-HDMI adapters. + */ + +/* + * When the EDID is unset because the HPD went low, then the CEC DPCD registers + * typically can no longer be read (true for a DP-to-HDMI adapter since it is + * powered by the HPD). However, some displays toggle the HPD off and on for a + * short period for one reason or another, and that would cause the CEC adapter + * to be removed and added again, even though nothing else changed. + * + * This module parameter sets a delay in seconds before the CEC adapter is + * actually unregistered. Only if the HPD does not return within that time will + * the CEC adapter be unregistered. + * + * If it is set to a value >= NEVER_UNREG_DELAY, then the CEC adapter will never + * be unregistered for as long as the connector remains registered. + * + * If it is set to 0, then the CEC adapter will be unregistered immediately as + * soon as the HPD disappears. + * + * The default is one second to prevent short HPD glitches from unregistering + * the CEC adapter. + * + * Note that for integrated HDMI branch devices that support CEC the DPCD + * registers remain available even if the HPD goes low since it is not powered + * by the HPD. In that case the CEC adapter will never be unregistered during + * the life time of the connector. At least, this is the theory since I do not + * have hardware with an integrated HDMI branch device that supports CEC. + */ +#define NEVER_UNREG_DELAY 1000 +static unsigned int drm_dp_cec_unregister_delay = 1; +module_param(drm_dp_cec_unregister_delay, uint, 0600); +MODULE_PARM_DESC(drm_dp_cec_unregister_delay, + "CEC unregister delay in seconds, 0: no delay, >= 1000: never unregister"); + +static int drm_dp_cec_adap_enable(struct cec_adapter *adap, bool enable) +{ + struct drm_dp_aux *aux = cec_get_drvdata(adap); + u32 val = enable ? DP_CEC_TUNNELING_ENABLE : 0; + ssize_t err = 0; + + err = drm_dp_dpcd_writeb(aux, DP_CEC_TUNNELING_CONTROL, val); + return (enable && err < 0) ? err : 0; +} + +static int drm_dp_cec_adap_log_addr(struct cec_adapter *adap, u8 addr) +{ + struct drm_dp_aux *aux = cec_get_drvdata(adap); + /* Bit 15 (logical address 15) should always be set */ + u16 la_mask = 1 << CEC_LOG_ADDR_BROADCAST; + u8 mask[2]; + ssize_t err; + + if (addr != CEC_LOG_ADDR_INVALID) + la_mask |= adap->log_addrs.log_addr_mask | (1 << addr); + mask[0] = la_mask & 0xff; + mask[1] = la_mask >> 8; + err = drm_dp_dpcd_write(aux, DP_CEC_LOGICAL_ADDRESS_MASK, mask, 2); + return (addr != CEC_LOG_ADDR_INVALID && err < 0) ? err : 0; +} + +static int drm_dp_cec_adap_transmit(struct cec_adapter *adap, u8 attempts, + u32 signal_free_time, struct cec_msg *msg) +{ + struct drm_dp_aux *aux = cec_get_drvdata(adap); + unsigned int retries = min(5, attempts - 1); + ssize_t err; + + err = drm_dp_dpcd_write(aux, DP_CEC_TX_MESSAGE_BUFFER, + msg->msg, msg->len); + if (err < 0) + return err; + + err = drm_dp_dpcd_writeb(aux, DP_CEC_TX_MESSAGE_INFO, + (msg->len - 1) | (retries << 4) | + DP_CEC_TX_MESSAGE_SEND); + return err < 0 ? err : 0; +} + +static int drm_dp_cec_adap_monitor_all_enable(struct cec_adapter *adap, + bool enable) +{ + struct drm_dp_aux *aux = cec_get_drvdata(adap); + ssize_t err; + u8 val; + + if (!(adap->capabilities & CEC_CAP_MONITOR_ALL)) + return 0; + + err = drm_dp_dpcd_readb(aux, DP_CEC_TUNNELING_CONTROL, &val); + if (err >= 0) { + if (enable) + val |= DP_CEC_SNOOPING_ENABLE; + else + val &= ~DP_CEC_SNOOPING_ENABLE; + err = drm_dp_dpcd_writeb(aux, DP_CEC_TUNNELING_CONTROL, val); + } + return (enable && err < 0) ? err : 0; +} + +static void drm_dp_cec_adap_status(struct cec_adapter *adap, + struct seq_file *file) +{ + struct drm_dp_aux *aux = cec_get_drvdata(adap); + struct drm_dp_desc desc; + struct drm_dp_dpcd_ident *id = &desc.ident; + + if (drm_dp_read_desc(aux, &desc, true)) + return; + seq_printf(file, "OUI: %*phD\n", + (int)sizeof(id->oui), id->oui); + seq_printf(file, "ID: %*pE\n", + (int)strnlen(id->device_id, sizeof(id->device_id)), + id->device_id); + seq_printf(file, "HW Rev: %d.%d\n", id->hw_rev >> 4, id->hw_rev & 0xf); + /* + * Show this both in decimal and hex: at least one vendor + * always reports this in hex. + */ + seq_printf(file, "FW/SW Rev: %d.%d (0x%02x.0x%02x)\n", + id->sw_major_rev, id->sw_minor_rev, + id->sw_major_rev, id->sw_minor_rev); +} + +static const struct cec_adap_ops drm_dp_cec_adap_ops = { + .adap_enable = drm_dp_cec_adap_enable, + .adap_log_addr = drm_dp_cec_adap_log_addr, + .adap_transmit = drm_dp_cec_adap_transmit, + .adap_monitor_all_enable = drm_dp_cec_adap_monitor_all_enable, + .adap_status = drm_dp_cec_adap_status, +}; + +static int drm_dp_cec_received(struct drm_dp_aux *aux) +{ + struct cec_adapter *adap = aux->cec.adap; + struct cec_msg msg; + u8 rx_msg_info; + ssize_t err; + + err = drm_dp_dpcd_readb(aux, DP_CEC_RX_MESSAGE_INFO, &rx_msg_info); + if (err < 0) + return err; + + if (!(rx_msg_info & DP_CEC_RX_MESSAGE_ENDED)) + return 0; + + msg.len = (rx_msg_info & DP_CEC_RX_MESSAGE_LEN_MASK) + 1; + err = drm_dp_dpcd_read(aux, DP_CEC_RX_MESSAGE_BUFFER, msg.msg, msg.len); + if (err < 0) + return err; + + cec_received_msg(adap, &msg); + return 0; +} + +static void drm_dp_cec_handle_irq(struct drm_dp_aux *aux) +{ + struct cec_adapter *adap = aux->cec.adap; + u8 flags; + + if (drm_dp_dpcd_readb(aux, DP_CEC_TUNNELING_IRQ_FLAGS, &flags) < 0) + return; + + if (flags & DP_CEC_RX_MESSAGE_INFO_VALID) + drm_dp_cec_received(aux); + + if (flags & DP_CEC_TX_MESSAGE_SENT) + cec_transmit_attempt_done(adap, CEC_TX_STATUS_OK); + else if (flags & DP_CEC_TX_LINE_ERROR) + cec_transmit_attempt_done(adap, CEC_TX_STATUS_ERROR | + CEC_TX_STATUS_MAX_RETRIES); + else if (flags & + (DP_CEC_TX_ADDRESS_NACK_ERROR | DP_CEC_TX_DATA_NACK_ERROR)) + cec_transmit_attempt_done(adap, CEC_TX_STATUS_NACK | + CEC_TX_STATUS_MAX_RETRIES); + drm_dp_dpcd_writeb(aux, DP_CEC_TUNNELING_IRQ_FLAGS, flags); +} + +/** + * drm_dp_cec_irq() - handle CEC interrupt, if any + * @aux: DisplayPort AUX channel + * + * Should be called when handling an IRQ_HPD request. If CEC-tunneling-over-AUX + * is present, then it will check for a CEC_IRQ and handle it accordingly. + */ +void drm_dp_cec_irq(struct drm_dp_aux *aux) +{ + u8 cec_irq; + int ret; + + /* No transfer function was set, so not a DP connector */ + if (!aux->transfer) + return; + + mutex_lock(&aux->cec.lock); + if (!aux->cec.adap) + goto unlock; + + ret = drm_dp_dpcd_readb(aux, DP_DEVICE_SERVICE_IRQ_VECTOR_ESI1, + &cec_irq); + if (ret < 0 || !(cec_irq & DP_CEC_IRQ)) + goto unlock; + + drm_dp_cec_handle_irq(aux); + drm_dp_dpcd_writeb(aux, DP_DEVICE_SERVICE_IRQ_VECTOR_ESI1, DP_CEC_IRQ); +unlock: + mutex_unlock(&aux->cec.lock); +} +EXPORT_SYMBOL(drm_dp_cec_irq); + +static bool drm_dp_cec_cap(struct drm_dp_aux *aux, u8 *cec_cap) +{ + u8 cap = 0; + + if (drm_dp_dpcd_readb(aux, DP_CEC_TUNNELING_CAPABILITY, &cap) != 1 || + !(cap & DP_CEC_TUNNELING_CAPABLE)) + return false; + if (cec_cap) + *cec_cap = cap; + return true; +} + +/* + * Called if the HPD was low for more than drm_dp_cec_unregister_delay + * seconds. This unregisters the CEC adapter. + */ +static void drm_dp_cec_unregister_work(struct work_struct *work) +{ + struct drm_dp_aux *aux = container_of(work, struct drm_dp_aux, + cec.unregister_work.work); + + mutex_lock(&aux->cec.lock); + cec_unregister_adapter(aux->cec.adap); + aux->cec.adap = NULL; + mutex_unlock(&aux->cec.lock); +} + +/* + * A new EDID is set. If there is no CEC adapter, then create one. If + * there was a CEC adapter, then check if the CEC adapter properties + * were unchanged and just update the CEC physical address. Otherwise + * unregister the old CEC adapter and create a new one. + */ +void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid) +{ + struct drm_connector *connector = aux->cec.connector; + u32 cec_caps = CEC_CAP_DEFAULTS | CEC_CAP_NEEDS_HPD | + CEC_CAP_CONNECTOR_INFO; + struct cec_connector_info conn_info; + unsigned int num_las = 1; + u8 cap; + + /* No transfer function was set, so not a DP connector */ + if (!aux->transfer) + return; + +#ifndef CONFIG_MEDIA_CEC_RC + /* + * CEC_CAP_RC is part of CEC_CAP_DEFAULTS, but it is stripped by + * cec_allocate_adapter() if CONFIG_MEDIA_CEC_RC is undefined. + * + * Do this here as well to ensure the tests against cec_caps are + * correct. + */ + cec_caps &= ~CEC_CAP_RC; +#endif + cancel_delayed_work_sync(&aux->cec.unregister_work); + + mutex_lock(&aux->cec.lock); + if (!drm_dp_cec_cap(aux, &cap)) { + /* CEC is not supported, unregister any existing adapter */ + cec_unregister_adapter(aux->cec.adap); + aux->cec.adap = NULL; + goto unlock; + } + + if (cap & DP_CEC_SNOOPING_CAPABLE) + cec_caps |= CEC_CAP_MONITOR_ALL; + if (cap & DP_CEC_MULTIPLE_LA_CAPABLE) + num_las = CEC_MAX_LOG_ADDRS; + + if (aux->cec.adap) { + if (aux->cec.adap->capabilities == cec_caps && + aux->cec.adap->available_log_addrs == num_las) { + /* Unchanged, so just set the phys addr */ + cec_s_phys_addr_from_edid(aux->cec.adap, edid); + goto unlock; + } + /* + * The capabilities changed, so unregister the old + * adapter first. + */ + cec_unregister_adapter(aux->cec.adap); + } + + /* Create a new adapter */ + aux->cec.adap = cec_allocate_adapter(&drm_dp_cec_adap_ops, + aux, connector->name, cec_caps, + num_las); + if (IS_ERR(aux->cec.adap)) { + aux->cec.adap = NULL; + goto unlock; + } + + cec_fill_conn_info_from_drm(&conn_info, connector); + cec_s_conn_info(aux->cec.adap, &conn_info); + + if (cec_register_adapter(aux->cec.adap, connector->dev->dev)) { + cec_delete_adapter(aux->cec.adap); + aux->cec.adap = NULL; + } else { + /* + * Update the phys addr for the new CEC adapter. When called + * from drm_dp_cec_register_connector() edid == NULL, so in + * that case the phys addr is just invalidated. + */ + cec_s_phys_addr_from_edid(aux->cec.adap, edid); + } +unlock: + mutex_unlock(&aux->cec.lock); +} +EXPORT_SYMBOL(drm_dp_cec_set_edid); + +/* + * The EDID disappeared (likely because of the HPD going down). + */ +void drm_dp_cec_unset_edid(struct drm_dp_aux *aux) +{ + /* No transfer function was set, so not a DP connector */ + if (!aux->transfer) + return; + + cancel_delayed_work_sync(&aux->cec.unregister_work); + + mutex_lock(&aux->cec.lock); + if (!aux->cec.adap) + goto unlock; + + cec_phys_addr_invalidate(aux->cec.adap); + /* + * We're done if we want to keep the CEC device + * (drm_dp_cec_unregister_delay is >= NEVER_UNREG_DELAY) or if the + * DPCD still indicates the CEC capability (expected for an integrated + * HDMI branch device). + */ + if (drm_dp_cec_unregister_delay < NEVER_UNREG_DELAY && + !drm_dp_cec_cap(aux, NULL)) { + /* + * Unregister the CEC adapter after drm_dp_cec_unregister_delay + * seconds. This to debounce short HPD off-and-on cycles from + * displays. + */ + schedule_delayed_work(&aux->cec.unregister_work, + drm_dp_cec_unregister_delay * HZ); + } +unlock: + mutex_unlock(&aux->cec.lock); +} +EXPORT_SYMBOL(drm_dp_cec_unset_edid); + +/** + * drm_dp_cec_register_connector() - register a new connector + * @aux: DisplayPort AUX channel + * @connector: drm connector + * + * A new connector was registered with associated CEC adapter name and + * CEC adapter parent device. After registering the name and parent + * drm_dp_cec_set_edid() is called to check if the connector supports + * CEC and to register a CEC adapter if that is the case. + */ +void drm_dp_cec_register_connector(struct drm_dp_aux *aux, + struct drm_connector *connector) +{ + WARN_ON(aux->cec.adap); + if (WARN_ON(!aux->transfer)) + return; + aux->cec.connector = connector; + INIT_DELAYED_WORK(&aux->cec.unregister_work, + drm_dp_cec_unregister_work); +} +EXPORT_SYMBOL(drm_dp_cec_register_connector); + +/** + * drm_dp_cec_unregister_connector() - unregister the CEC adapter, if any + * @aux: DisplayPort AUX channel + */ +void drm_dp_cec_unregister_connector(struct drm_dp_aux *aux) +{ + if (!aux->cec.adap) + return; + cancel_delayed_work_sync(&aux->cec.unregister_work); + cec_unregister_adapter(aux->cec.adap); + aux->cec.adap = NULL; +} +EXPORT_SYMBOL(drm_dp_cec_unregister_connector); diff --git a/drivers/gpu/drm/display/drm_dp_dual_mode_helper.c b/drivers/gpu/drm/display/drm_dp_dual_mode_helper.c new file mode 100644 index 000000000..bd61e2077 --- /dev/null +++ b/drivers/gpu/drm/display/drm_dp_dual_mode_helper.c @@ -0,0 +1,537 @@ +/* + * Copyright © 2016 Intel Corporation + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + */ + +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/export.h> +#include <linux/i2c.h> +#include <linux/slab.h> +#include <linux/string.h> + +#include <drm/display/drm_dp_dual_mode_helper.h> +#include <drm/drm_device.h> +#include <drm/drm_print.h> + +/** + * DOC: dp dual mode helpers + * + * Helper functions to deal with DP dual mode (aka. DP++) adaptors. + * + * Type 1: + * Adaptor registers (if any) and the sink DDC bus may be accessed via I2C. + * + * Type 2: + * Adaptor registers and sink DDC bus can be accessed either via I2C or + * I2C-over-AUX. Source devices may choose to implement either of these + * access methods. + */ + +#define DP_DUAL_MODE_SLAVE_ADDRESS 0x40 + +/** + * drm_dp_dual_mode_read - Read from the DP dual mode adaptor register(s) + * @adapter: I2C adapter for the DDC bus + * @offset: register offset + * @buffer: buffer for return data + * @size: sizo of the buffer + * + * Reads @size bytes from the DP dual mode adaptor registers + * starting at @offset. + * + * Returns: + * 0 on success, negative error code on failure + */ +ssize_t drm_dp_dual_mode_read(struct i2c_adapter *adapter, + u8 offset, void *buffer, size_t size) +{ + u8 zero = 0; + char *tmpbuf = NULL; + /* + * As sub-addressing is not supported by all adaptors, + * always explicitly read from the start and discard + * any bytes that come before the requested offset. + * This way, no matter whether the adaptor supports it + * or not, we'll end up reading the proper data. + */ + struct i2c_msg msgs[] = { + { + .addr = DP_DUAL_MODE_SLAVE_ADDRESS, + .flags = 0, + .len = 1, + .buf = &zero, + }, + { + .addr = DP_DUAL_MODE_SLAVE_ADDRESS, + .flags = I2C_M_RD, + .len = size + offset, + .buf = buffer, + }, + }; + int ret; + + if (offset) { + tmpbuf = kmalloc(size + offset, GFP_KERNEL); + if (!tmpbuf) + return -ENOMEM; + + msgs[1].buf = tmpbuf; + } + + ret = i2c_transfer(adapter, msgs, ARRAY_SIZE(msgs)); + if (tmpbuf) + memcpy(buffer, tmpbuf + offset, size); + + kfree(tmpbuf); + + if (ret < 0) + return ret; + if (ret != ARRAY_SIZE(msgs)) + return -EPROTO; + + return 0; +} +EXPORT_SYMBOL(drm_dp_dual_mode_read); + +/** + * drm_dp_dual_mode_write - Write to the DP dual mode adaptor register(s) + * @adapter: I2C adapter for the DDC bus + * @offset: register offset + * @buffer: buffer for write data + * @size: sizo of the buffer + * + * Writes @size bytes to the DP dual mode adaptor registers + * starting at @offset. + * + * Returns: + * 0 on success, negative error code on failure + */ +ssize_t drm_dp_dual_mode_write(struct i2c_adapter *adapter, + u8 offset, const void *buffer, size_t size) +{ + struct i2c_msg msg = { + .addr = DP_DUAL_MODE_SLAVE_ADDRESS, + .flags = 0, + .len = 1 + size, + .buf = NULL, + }; + void *data; + int ret; + + data = kmalloc(msg.len, GFP_KERNEL); + if (!data) + return -ENOMEM; + + msg.buf = data; + + memcpy(data, &offset, 1); + memcpy(data + 1, buffer, size); + + ret = i2c_transfer(adapter, &msg, 1); + + kfree(data); + + if (ret < 0) + return ret; + if (ret != 1) + return -EPROTO; + + return 0; +} +EXPORT_SYMBOL(drm_dp_dual_mode_write); + +static bool is_hdmi_adaptor(const char hdmi_id[DP_DUAL_MODE_HDMI_ID_LEN]) +{ + static const char dp_dual_mode_hdmi_id[DP_DUAL_MODE_HDMI_ID_LEN] = + "DP-HDMI ADAPTOR\x04"; + + return memcmp(hdmi_id, dp_dual_mode_hdmi_id, + sizeof(dp_dual_mode_hdmi_id)) == 0; +} + +static bool is_type1_adaptor(uint8_t adaptor_id) +{ + return adaptor_id == 0 || adaptor_id == 0xff; +} + +static bool is_type2_adaptor(uint8_t adaptor_id) +{ + return adaptor_id == (DP_DUAL_MODE_TYPE_TYPE2 | + DP_DUAL_MODE_REV_TYPE2); +} + +static bool is_lspcon_adaptor(const char hdmi_id[DP_DUAL_MODE_HDMI_ID_LEN], + const uint8_t adaptor_id) +{ + return is_hdmi_adaptor(hdmi_id) && + (adaptor_id == (DP_DUAL_MODE_TYPE_TYPE2 | + DP_DUAL_MODE_TYPE_HAS_DPCD)); +} + +/** + * drm_dp_dual_mode_detect - Identify the DP dual mode adaptor + * @dev: &drm_device to use + * @adapter: I2C adapter for the DDC bus + * + * Attempt to identify the type of the DP dual mode adaptor used. + * + * Note that when the answer is @DRM_DP_DUAL_MODE_UNKNOWN it's not + * certain whether we're dealing with a native HDMI port or + * a type 1 DVI dual mode adaptor. The driver will have to use + * some other hardware/driver specific mechanism to make that + * distinction. + * + * Returns: + * The type of the DP dual mode adaptor used + */ +enum drm_dp_dual_mode_type drm_dp_dual_mode_detect(const struct drm_device *dev, + struct i2c_adapter *adapter) +{ + char hdmi_id[DP_DUAL_MODE_HDMI_ID_LEN] = {}; + uint8_t adaptor_id = 0x00; + ssize_t ret; + + /* + * Let's see if the adaptor is there the by reading the + * HDMI ID registers. + * + * Note that type 1 DVI adaptors are not required to implemnt + * any registers, and that presents a problem for detection. + * If the i2c transfer is nacked, we may or may not be dealing + * with a type 1 DVI adaptor. Some other mechanism of detecting + * the presence of the adaptor is required. One way would be + * to check the state of the CONFIG1 pin, Another method would + * simply require the driver to know whether the port is a DP++ + * port or a native HDMI port. Both of these methods are entirely + * hardware/driver specific so we can't deal with them here. + */ + ret = drm_dp_dual_mode_read(adapter, DP_DUAL_MODE_HDMI_ID, + hdmi_id, sizeof(hdmi_id)); + drm_dbg_kms(dev, "DP dual mode HDMI ID: %*pE (err %zd)\n", + ret ? 0 : (int)sizeof(hdmi_id), hdmi_id, ret); + if (ret) + return DRM_DP_DUAL_MODE_UNKNOWN; + + ret = drm_dp_dual_mode_read(adapter, DP_DUAL_MODE_ADAPTOR_ID, + &adaptor_id, sizeof(adaptor_id)); + drm_dbg_kms(dev, "DP dual mode adaptor ID: %02x (err %zd)\n", adaptor_id, ret); + if (ret == 0) { + if (is_lspcon_adaptor(hdmi_id, adaptor_id)) + return DRM_DP_DUAL_MODE_LSPCON; + if (is_type2_adaptor(adaptor_id)) { + if (is_hdmi_adaptor(hdmi_id)) + return DRM_DP_DUAL_MODE_TYPE2_HDMI; + else + return DRM_DP_DUAL_MODE_TYPE2_DVI; + } + /* + * If not a proper type 1 ID, still assume type 1, but let + * the user know that we may have misdetected the type. + */ + if (!is_type1_adaptor(adaptor_id)) + drm_err(dev, "Unexpected DP dual mode adaptor ID %02x\n", adaptor_id); + + } + + if (is_hdmi_adaptor(hdmi_id)) + return DRM_DP_DUAL_MODE_TYPE1_HDMI; + else + return DRM_DP_DUAL_MODE_TYPE1_DVI; +} +EXPORT_SYMBOL(drm_dp_dual_mode_detect); + +/** + * drm_dp_dual_mode_max_tmds_clock - Max TMDS clock for DP dual mode adaptor + * @dev: &drm_device to use + * @type: DP dual mode adaptor type + * @adapter: I2C adapter for the DDC bus + * + * Determine the max TMDS clock the adaptor supports based on the + * type of the dual mode adaptor and the DP_DUAL_MODE_MAX_TMDS_CLOCK + * register (on type2 adaptors). As some type 1 adaptors have + * problems with registers (see comments in drm_dp_dual_mode_detect()) + * we don't read the register on those, instead we simply assume + * a 165 MHz limit based on the specification. + * + * Returns: + * Maximum supported TMDS clock rate for the DP dual mode adaptor in kHz. + */ +int drm_dp_dual_mode_max_tmds_clock(const struct drm_device *dev, enum drm_dp_dual_mode_type type, + struct i2c_adapter *adapter) +{ + uint8_t max_tmds_clock; + ssize_t ret; + + /* native HDMI so no limit */ + if (type == DRM_DP_DUAL_MODE_NONE) + return 0; + + /* + * Type 1 adaptors are limited to 165MHz + * Type 2 adaptors can tells us their limit + */ + if (type < DRM_DP_DUAL_MODE_TYPE2_DVI) + return 165000; + + ret = drm_dp_dual_mode_read(adapter, DP_DUAL_MODE_MAX_TMDS_CLOCK, + &max_tmds_clock, sizeof(max_tmds_clock)); + if (ret || max_tmds_clock == 0x00 || max_tmds_clock == 0xff) { + drm_dbg_kms(dev, "Failed to query max TMDS clock\n"); + return 165000; + } + + return max_tmds_clock * 5000 / 2; +} +EXPORT_SYMBOL(drm_dp_dual_mode_max_tmds_clock); + +/** + * drm_dp_dual_mode_get_tmds_output - Get the state of the TMDS output buffers in the DP dual mode adaptor + * @dev: &drm_device to use + * @type: DP dual mode adaptor type + * @adapter: I2C adapter for the DDC bus + * @enabled: current state of the TMDS output buffers + * + * Get the state of the TMDS output buffers in the adaptor. For + * type2 adaptors this is queried from the DP_DUAL_MODE_TMDS_OEN + * register. As some type 1 adaptors have problems with registers + * (see comments in drm_dp_dual_mode_detect()) we don't read the + * register on those, instead we simply assume that the buffers + * are always enabled. + * + * Returns: + * 0 on success, negative error code on failure + */ +int drm_dp_dual_mode_get_tmds_output(const struct drm_device *dev, + enum drm_dp_dual_mode_type type, struct i2c_adapter *adapter, + bool *enabled) +{ + uint8_t tmds_oen; + ssize_t ret; + + if (type < DRM_DP_DUAL_MODE_TYPE2_DVI) { + *enabled = true; + return 0; + } + + ret = drm_dp_dual_mode_read(adapter, DP_DUAL_MODE_TMDS_OEN, + &tmds_oen, sizeof(tmds_oen)); + if (ret) { + drm_dbg_kms(dev, "Failed to query state of TMDS output buffers\n"); + return ret; + } + + *enabled = !(tmds_oen & DP_DUAL_MODE_TMDS_DISABLE); + + return 0; +} +EXPORT_SYMBOL(drm_dp_dual_mode_get_tmds_output); + +/** + * drm_dp_dual_mode_set_tmds_output - Enable/disable TMDS output buffers in the DP dual mode adaptor + * @dev: &drm_device to use + * @type: DP dual mode adaptor type + * @adapter: I2C adapter for the DDC bus + * @enable: enable (as opposed to disable) the TMDS output buffers + * + * Set the state of the TMDS output buffers in the adaptor. For + * type2 this is set via the DP_DUAL_MODE_TMDS_OEN register. + * Type1 adaptors do not support any register writes. + * + * Returns: + * 0 on success, negative error code on failure + */ +int drm_dp_dual_mode_set_tmds_output(const struct drm_device *dev, enum drm_dp_dual_mode_type type, + struct i2c_adapter *adapter, bool enable) +{ + uint8_t tmds_oen = enable ? 0 : DP_DUAL_MODE_TMDS_DISABLE; + ssize_t ret; + int retry; + + if (type < DRM_DP_DUAL_MODE_TYPE2_DVI) + return 0; + + /* + * LSPCON adapters in low-power state may ignore the first write, so + * read back and verify the written value a few times. + */ + for (retry = 0; retry < 3; retry++) { + uint8_t tmp; + + ret = drm_dp_dual_mode_write(adapter, DP_DUAL_MODE_TMDS_OEN, + &tmds_oen, sizeof(tmds_oen)); + if (ret) { + drm_dbg_kms(dev, "Failed to %s TMDS output buffers (%d attempts)\n", + enable ? "enable" : "disable", retry + 1); + return ret; + } + + ret = drm_dp_dual_mode_read(adapter, DP_DUAL_MODE_TMDS_OEN, + &tmp, sizeof(tmp)); + if (ret) { + drm_dbg_kms(dev, + "I2C read failed during TMDS output buffer %s (%d attempts)\n", + enable ? "enabling" : "disabling", retry + 1); + return ret; + } + + if (tmp == tmds_oen) + return 0; + } + + drm_dbg_kms(dev, "I2C write value mismatch during TMDS output buffer %s\n", + enable ? "enabling" : "disabling"); + + return -EIO; +} +EXPORT_SYMBOL(drm_dp_dual_mode_set_tmds_output); + +/** + * drm_dp_get_dual_mode_type_name - Get the name of the DP dual mode adaptor type as a string + * @type: DP dual mode adaptor type + * + * Returns: + * String representation of the DP dual mode adaptor type + */ +const char *drm_dp_get_dual_mode_type_name(enum drm_dp_dual_mode_type type) +{ + switch (type) { + case DRM_DP_DUAL_MODE_NONE: + return "none"; + case DRM_DP_DUAL_MODE_TYPE1_DVI: + return "type 1 DVI"; + case DRM_DP_DUAL_MODE_TYPE1_HDMI: + return "type 1 HDMI"; + case DRM_DP_DUAL_MODE_TYPE2_DVI: + return "type 2 DVI"; + case DRM_DP_DUAL_MODE_TYPE2_HDMI: + return "type 2 HDMI"; + case DRM_DP_DUAL_MODE_LSPCON: + return "lspcon"; + default: + WARN_ON(type != DRM_DP_DUAL_MODE_UNKNOWN); + return "unknown"; + } +} +EXPORT_SYMBOL(drm_dp_get_dual_mode_type_name); + +/** + * drm_lspcon_get_mode: Get LSPCON's current mode of operation by + * reading offset (0x80, 0x41) + * @dev: &drm_device to use + * @adapter: I2C-over-aux adapter + * @mode: current lspcon mode of operation output variable + * + * Returns: + * 0 on success, sets the current_mode value to appropriate mode + * -error on failure + */ +int drm_lspcon_get_mode(const struct drm_device *dev, struct i2c_adapter *adapter, + enum drm_lspcon_mode *mode) +{ + u8 data; + int ret = 0; + int retry; + + if (!mode) { + drm_err(dev, "NULL input\n"); + return -EINVAL; + } + + /* Read Status: i2c over aux */ + for (retry = 0; retry < 6; retry++) { + if (retry) + usleep_range(500, 1000); + + ret = drm_dp_dual_mode_read(adapter, + DP_DUAL_MODE_LSPCON_CURRENT_MODE, + &data, sizeof(data)); + if (!ret) + break; + } + + if (ret < 0) { + drm_dbg_kms(dev, "LSPCON read(0x80, 0x41) failed\n"); + return -EFAULT; + } + + if (data & DP_DUAL_MODE_LSPCON_MODE_PCON) + *mode = DRM_LSPCON_MODE_PCON; + else + *mode = DRM_LSPCON_MODE_LS; + return 0; +} +EXPORT_SYMBOL(drm_lspcon_get_mode); + +/** + * drm_lspcon_set_mode: Change LSPCON's mode of operation by + * writing offset (0x80, 0x40) + * @dev: &drm_device to use + * @adapter: I2C-over-aux adapter + * @mode: required mode of operation + * + * Returns: + * 0 on success, -error on failure/timeout + */ +int drm_lspcon_set_mode(const struct drm_device *dev, struct i2c_adapter *adapter, + enum drm_lspcon_mode mode) +{ + u8 data = 0; + int ret; + int time_out = 200; + enum drm_lspcon_mode current_mode; + + if (mode == DRM_LSPCON_MODE_PCON) + data = DP_DUAL_MODE_LSPCON_MODE_PCON; + + /* Change mode */ + ret = drm_dp_dual_mode_write(adapter, DP_DUAL_MODE_LSPCON_MODE_CHANGE, + &data, sizeof(data)); + if (ret < 0) { + drm_err(dev, "LSPCON mode change failed\n"); + return ret; + } + + /* + * Confirm mode change by reading the status bit. + * Sometimes, it takes a while to change the mode, + * so wait and retry until time out or done. + */ + do { + ret = drm_lspcon_get_mode(dev, adapter, ¤t_mode); + if (ret) { + drm_err(dev, "can't confirm LSPCON mode change\n"); + return ret; + } else { + if (current_mode != mode) { + msleep(10); + time_out -= 10; + } else { + drm_dbg_kms(dev, "LSPCON mode changed to %s\n", + mode == DRM_LSPCON_MODE_LS ? "LS" : "PCON"); + return 0; + } + } + } while (time_out); + + drm_err(dev, "LSPCON mode change timed out\n"); + return -ETIMEDOUT; +} +EXPORT_SYMBOL(drm_lspcon_set_mode); diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c new file mode 100644 index 000000000..16565a0a5 --- /dev/null +++ b/drivers/gpu/drm/display/drm_dp_helper.c @@ -0,0 +1,3893 @@ +/* + * Copyright © 2009 Keith Packard + * + * Permission to use, copy, modify, distribute, and sell this software and its + * documentation for any purpose is hereby granted without fee, provided that + * the above copyright notice appear in all copies and that both that copyright + * notice and this permission notice appear in supporting documentation, and + * that the name of the copyright holders not be used in advertising or + * publicity pertaining to distribution of the software without specific, + * written prior permission. The copyright holders make no representations + * about the suitability of this software for any purpose. It is provided "as + * is" without express or implied warranty. + * + * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, + * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO + * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR + * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, + * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER + * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE + * OF THIS SOFTWARE. + */ + +#include <linux/backlight.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/seq_file.h> +#include <linux/string_helpers.h> +#include <linux/dynamic_debug.h> + +#include <drm/display/drm_dp_helper.h> +#include <drm/display/drm_dp_mst_helper.h> +#include <drm/drm_edid.h> +#include <drm/drm_print.h> +#include <drm/drm_vblank.h> +#include <drm/drm_panel.h> + +#include "drm_dp_helper_internal.h" + +DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0, + "DRM_UT_CORE", + "DRM_UT_DRIVER", + "DRM_UT_KMS", + "DRM_UT_PRIME", + "DRM_UT_ATOMIC", + "DRM_UT_VBL", + "DRM_UT_STATE", + "DRM_UT_LEASE", + "DRM_UT_DP", + "DRM_UT_DRMRES"); + +struct dp_aux_backlight { + struct backlight_device *base; + struct drm_dp_aux *aux; + struct drm_edp_backlight_info info; + bool enabled; +}; + +/** + * DOC: dp helpers + * + * These functions contain some common logic and helpers at various abstraction + * levels to deal with Display Port sink devices and related things like DP aux + * channel transfers, EDID reading over DP aux channels, decoding certain DPCD + * blocks, ... + */ + +/* Helpers for DP link training */ +static u8 dp_link_status(const u8 link_status[DP_LINK_STATUS_SIZE], int r) +{ + return link_status[r - DP_LANE0_1_STATUS]; +} + +static u8 dp_get_lane_status(const u8 link_status[DP_LINK_STATUS_SIZE], + int lane) +{ + int i = DP_LANE0_1_STATUS + (lane >> 1); + int s = (lane & 1) * 4; + u8 l = dp_link_status(link_status, i); + + return (l >> s) & 0xf; +} + +bool drm_dp_channel_eq_ok(const u8 link_status[DP_LINK_STATUS_SIZE], + int lane_count) +{ + u8 lane_align; + u8 lane_status; + int lane; + + lane_align = dp_link_status(link_status, + DP_LANE_ALIGN_STATUS_UPDATED); + if ((lane_align & DP_INTERLANE_ALIGN_DONE) == 0) + return false; + for (lane = 0; lane < lane_count; lane++) { + lane_status = dp_get_lane_status(link_status, lane); + if ((lane_status & DP_CHANNEL_EQ_BITS) != DP_CHANNEL_EQ_BITS) + return false; + } + return true; +} +EXPORT_SYMBOL(drm_dp_channel_eq_ok); + +bool drm_dp_clock_recovery_ok(const u8 link_status[DP_LINK_STATUS_SIZE], + int lane_count) +{ + int lane; + u8 lane_status; + + for (lane = 0; lane < lane_count; lane++) { + lane_status = dp_get_lane_status(link_status, lane); + if ((lane_status & DP_LANE_CR_DONE) == 0) + return false; + } + return true; +} +EXPORT_SYMBOL(drm_dp_clock_recovery_ok); + +u8 drm_dp_get_adjust_request_voltage(const u8 link_status[DP_LINK_STATUS_SIZE], + int lane) +{ + int i = DP_ADJUST_REQUEST_LANE0_1 + (lane >> 1); + int s = ((lane & 1) ? + DP_ADJUST_VOLTAGE_SWING_LANE1_SHIFT : + DP_ADJUST_VOLTAGE_SWING_LANE0_SHIFT); + u8 l = dp_link_status(link_status, i); + + return ((l >> s) & 0x3) << DP_TRAIN_VOLTAGE_SWING_SHIFT; +} +EXPORT_SYMBOL(drm_dp_get_adjust_request_voltage); + +u8 drm_dp_get_adjust_request_pre_emphasis(const u8 link_status[DP_LINK_STATUS_SIZE], + int lane) +{ + int i = DP_ADJUST_REQUEST_LANE0_1 + (lane >> 1); + int s = ((lane & 1) ? + DP_ADJUST_PRE_EMPHASIS_LANE1_SHIFT : + DP_ADJUST_PRE_EMPHASIS_LANE0_SHIFT); + u8 l = dp_link_status(link_status, i); + + return ((l >> s) & 0x3) << DP_TRAIN_PRE_EMPHASIS_SHIFT; +} +EXPORT_SYMBOL(drm_dp_get_adjust_request_pre_emphasis); + +/* DP 2.0 128b/132b */ +u8 drm_dp_get_adjust_tx_ffe_preset(const u8 link_status[DP_LINK_STATUS_SIZE], + int lane) +{ + int i = DP_ADJUST_REQUEST_LANE0_1 + (lane >> 1); + int s = ((lane & 1) ? + DP_ADJUST_TX_FFE_PRESET_LANE1_SHIFT : + DP_ADJUST_TX_FFE_PRESET_LANE0_SHIFT); + u8 l = dp_link_status(link_status, i); + + return (l >> s) & 0xf; +} +EXPORT_SYMBOL(drm_dp_get_adjust_tx_ffe_preset); + +/* DP 2.0 errata for 128b/132b */ +bool drm_dp_128b132b_lane_channel_eq_done(const u8 link_status[DP_LINK_STATUS_SIZE], + int lane_count) +{ + u8 lane_align, lane_status; + int lane; + + lane_align = dp_link_status(link_status, DP_LANE_ALIGN_STATUS_UPDATED); + if (!(lane_align & DP_INTERLANE_ALIGN_DONE)) + return false; + + for (lane = 0; lane < lane_count; lane++) { + lane_status = dp_get_lane_status(link_status, lane); + if (!(lane_status & DP_LANE_CHANNEL_EQ_DONE)) + return false; + } + return true; +} +EXPORT_SYMBOL(drm_dp_128b132b_lane_channel_eq_done); + +/* DP 2.0 errata for 128b/132b */ +bool drm_dp_128b132b_lane_symbol_locked(const u8 link_status[DP_LINK_STATUS_SIZE], + int lane_count) +{ + u8 lane_status; + int lane; + + for (lane = 0; lane < lane_count; lane++) { + lane_status = dp_get_lane_status(link_status, lane); + if (!(lane_status & DP_LANE_SYMBOL_LOCKED)) + return false; + } + return true; +} +EXPORT_SYMBOL(drm_dp_128b132b_lane_symbol_locked); + +/* DP 2.0 errata for 128b/132b */ +bool drm_dp_128b132b_eq_interlane_align_done(const u8 link_status[DP_LINK_STATUS_SIZE]) +{ + u8 status = dp_link_status(link_status, DP_LANE_ALIGN_STATUS_UPDATED); + + return status & DP_128B132B_DPRX_EQ_INTERLANE_ALIGN_DONE; +} +EXPORT_SYMBOL(drm_dp_128b132b_eq_interlane_align_done); + +/* DP 2.0 errata for 128b/132b */ +bool drm_dp_128b132b_cds_interlane_align_done(const u8 link_status[DP_LINK_STATUS_SIZE]) +{ + u8 status = dp_link_status(link_status, DP_LANE_ALIGN_STATUS_UPDATED); + + return status & DP_128B132B_DPRX_CDS_INTERLANE_ALIGN_DONE; +} +EXPORT_SYMBOL(drm_dp_128b132b_cds_interlane_align_done); + +/* DP 2.0 errata for 128b/132b */ +bool drm_dp_128b132b_link_training_failed(const u8 link_status[DP_LINK_STATUS_SIZE]) +{ + u8 status = dp_link_status(link_status, DP_LANE_ALIGN_STATUS_UPDATED); + + return status & DP_128B132B_LT_FAILED; +} +EXPORT_SYMBOL(drm_dp_128b132b_link_training_failed); + +static int __8b10b_clock_recovery_delay_us(const struct drm_dp_aux *aux, u8 rd_interval) +{ + if (rd_interval > 4) + drm_dbg_kms(aux->drm_dev, "%s: invalid AUX interval 0x%02x (max 4)\n", + aux->name, rd_interval); + + if (rd_interval == 0) + return 100; + + return rd_interval * 4 * USEC_PER_MSEC; +} + +static int __8b10b_channel_eq_delay_us(const struct drm_dp_aux *aux, u8 rd_interval) +{ + if (rd_interval > 4) + drm_dbg_kms(aux->drm_dev, "%s: invalid AUX interval 0x%02x (max 4)\n", + aux->name, rd_interval); + + if (rd_interval == 0) + return 400; + + return rd_interval * 4 * USEC_PER_MSEC; +} + +static int __128b132b_channel_eq_delay_us(const struct drm_dp_aux *aux, u8 rd_interval) +{ + switch (rd_interval) { + default: + drm_dbg_kms(aux->drm_dev, "%s: invalid AUX interval 0x%02x\n", + aux->name, rd_interval); + fallthrough; + case DP_128B132B_TRAINING_AUX_RD_INTERVAL_400_US: + return 400; + case DP_128B132B_TRAINING_AUX_RD_INTERVAL_4_MS: + return 4000; + case DP_128B132B_TRAINING_AUX_RD_INTERVAL_8_MS: + return 8000; + case DP_128B132B_TRAINING_AUX_RD_INTERVAL_12_MS: + return 12000; + case DP_128B132B_TRAINING_AUX_RD_INTERVAL_16_MS: + return 16000; + case DP_128B132B_TRAINING_AUX_RD_INTERVAL_32_MS: + return 32000; + case DP_128B132B_TRAINING_AUX_RD_INTERVAL_64_MS: + return 64000; + } +} + +/* + * The link training delays are different for: + * + * - Clock recovery vs. channel equalization + * - DPRX vs. LTTPR + * - 128b/132b vs. 8b/10b + * - DPCD rev 1.3 vs. later + * + * Get the correct delay in us, reading DPCD if necessary. + */ +static int __read_delay(struct drm_dp_aux *aux, const u8 dpcd[DP_RECEIVER_CAP_SIZE], + enum drm_dp_phy dp_phy, bool uhbr, bool cr) +{ + int (*parse)(const struct drm_dp_aux *aux, u8 rd_interval); + unsigned int offset; + u8 rd_interval, mask; + + if (dp_phy == DP_PHY_DPRX) { + if (uhbr) { + if (cr) + return 100; + + offset = DP_128B132B_TRAINING_AUX_RD_INTERVAL; + mask = DP_128B132B_TRAINING_AUX_RD_INTERVAL_MASK; + parse = __128b132b_channel_eq_delay_us; + } else { + if (cr && dpcd[DP_DPCD_REV] >= DP_DPCD_REV_14) + return 100; + + offset = DP_TRAINING_AUX_RD_INTERVAL; + mask = DP_TRAINING_AUX_RD_MASK; + if (cr) + parse = __8b10b_clock_recovery_delay_us; + else + parse = __8b10b_channel_eq_delay_us; + } + } else { + if (uhbr) { + offset = DP_128B132B_TRAINING_AUX_RD_INTERVAL_PHY_REPEATER(dp_phy); + mask = DP_128B132B_TRAINING_AUX_RD_INTERVAL_MASK; + parse = __128b132b_channel_eq_delay_us; + } else { + if (cr) + return 100; + + offset = DP_TRAINING_AUX_RD_INTERVAL_PHY_REPEATER(dp_phy); + mask = DP_TRAINING_AUX_RD_MASK; + parse = __8b10b_channel_eq_delay_us; + } + } + + if (offset < DP_RECEIVER_CAP_SIZE) { + rd_interval = dpcd[offset]; + } else { + if (drm_dp_dpcd_readb(aux, offset, &rd_interval) != 1) { + drm_dbg_kms(aux->drm_dev, "%s: failed rd interval read\n", + aux->name); + /* arbitrary default delay */ + return 400; + } + } + + return parse(aux, rd_interval & mask); +} + +int drm_dp_read_clock_recovery_delay(struct drm_dp_aux *aux, const u8 dpcd[DP_RECEIVER_CAP_SIZE], + enum drm_dp_phy dp_phy, bool uhbr) +{ + return __read_delay(aux, dpcd, dp_phy, uhbr, true); +} +EXPORT_SYMBOL(drm_dp_read_clock_recovery_delay); + +int drm_dp_read_channel_eq_delay(struct drm_dp_aux *aux, const u8 dpcd[DP_RECEIVER_CAP_SIZE], + enum drm_dp_phy dp_phy, bool uhbr) +{ + return __read_delay(aux, dpcd, dp_phy, uhbr, false); +} +EXPORT_SYMBOL(drm_dp_read_channel_eq_delay); + +/* Per DP 2.0 Errata */ +int drm_dp_128b132b_read_aux_rd_interval(struct drm_dp_aux *aux) +{ + int unit; + u8 val; + + if (drm_dp_dpcd_readb(aux, DP_128B132B_TRAINING_AUX_RD_INTERVAL, &val) != 1) { + drm_err(aux->drm_dev, "%s: failed rd interval read\n", + aux->name); + /* default to max */ + val = DP_128B132B_TRAINING_AUX_RD_INTERVAL_MASK; + } + + unit = (val & DP_128B132B_TRAINING_AUX_RD_INTERVAL_1MS_UNIT) ? 1 : 2; + val &= DP_128B132B_TRAINING_AUX_RD_INTERVAL_MASK; + + return (val + 1) * unit * 1000; +} +EXPORT_SYMBOL(drm_dp_128b132b_read_aux_rd_interval); + +void drm_dp_link_train_clock_recovery_delay(const struct drm_dp_aux *aux, + const u8 dpcd[DP_RECEIVER_CAP_SIZE]) +{ + u8 rd_interval = dpcd[DP_TRAINING_AUX_RD_INTERVAL] & + DP_TRAINING_AUX_RD_MASK; + int delay_us; + + if (dpcd[DP_DPCD_REV] >= DP_DPCD_REV_14) + delay_us = 100; + else + delay_us = __8b10b_clock_recovery_delay_us(aux, rd_interval); + + usleep_range(delay_us, delay_us * 2); +} +EXPORT_SYMBOL(drm_dp_link_train_clock_recovery_delay); + +static void __drm_dp_link_train_channel_eq_delay(const struct drm_dp_aux *aux, + u8 rd_interval) +{ + int delay_us = __8b10b_channel_eq_delay_us(aux, rd_interval); + + usleep_range(delay_us, delay_us * 2); +} + +void drm_dp_link_train_channel_eq_delay(const struct drm_dp_aux *aux, + const u8 dpcd[DP_RECEIVER_CAP_SIZE]) +{ + __drm_dp_link_train_channel_eq_delay(aux, + dpcd[DP_TRAINING_AUX_RD_INTERVAL] & + DP_TRAINING_AUX_RD_MASK); +} +EXPORT_SYMBOL(drm_dp_link_train_channel_eq_delay); + +/** + * drm_dp_phy_name() - Get the name of the given DP PHY + * @dp_phy: The DP PHY identifier + * + * Given the @dp_phy, get a user friendly name of the DP PHY, either "DPRX" or + * "LTTPR <N>", or "<INVALID DP PHY>" on errors. The returned string is always + * non-NULL and valid. + * + * Returns: Name of the DP PHY. + */ +const char *drm_dp_phy_name(enum drm_dp_phy dp_phy) +{ + static const char * const phy_names[] = { + [DP_PHY_DPRX] = "DPRX", + [DP_PHY_LTTPR1] = "LTTPR 1", + [DP_PHY_LTTPR2] = "LTTPR 2", + [DP_PHY_LTTPR3] = "LTTPR 3", + [DP_PHY_LTTPR4] = "LTTPR 4", + [DP_PHY_LTTPR5] = "LTTPR 5", + [DP_PHY_LTTPR6] = "LTTPR 6", + [DP_PHY_LTTPR7] = "LTTPR 7", + [DP_PHY_LTTPR8] = "LTTPR 8", + }; + + if (dp_phy < 0 || dp_phy >= ARRAY_SIZE(phy_names) || + WARN_ON(!phy_names[dp_phy])) + return "<INVALID DP PHY>"; + + return phy_names[dp_phy]; +} +EXPORT_SYMBOL(drm_dp_phy_name); + +void drm_dp_lttpr_link_train_clock_recovery_delay(void) +{ + usleep_range(100, 200); +} +EXPORT_SYMBOL(drm_dp_lttpr_link_train_clock_recovery_delay); + +static u8 dp_lttpr_phy_cap(const u8 phy_cap[DP_LTTPR_PHY_CAP_SIZE], int r) +{ + return phy_cap[r - DP_TRAINING_AUX_RD_INTERVAL_PHY_REPEATER1]; +} + +void drm_dp_lttpr_link_train_channel_eq_delay(const struct drm_dp_aux *aux, + const u8 phy_cap[DP_LTTPR_PHY_CAP_SIZE]) +{ + u8 interval = dp_lttpr_phy_cap(phy_cap, + DP_TRAINING_AUX_RD_INTERVAL_PHY_REPEATER1) & + DP_TRAINING_AUX_RD_MASK; + + __drm_dp_link_train_channel_eq_delay(aux, interval); +} +EXPORT_SYMBOL(drm_dp_lttpr_link_train_channel_eq_delay); + +u8 drm_dp_link_rate_to_bw_code(int link_rate) +{ + switch (link_rate) { + case 1000000: + return DP_LINK_BW_10; + case 1350000: + return DP_LINK_BW_13_5; + case 2000000: + return DP_LINK_BW_20; + default: + /* Spec says link_bw = link_rate / 0.27Gbps */ + return link_rate / 27000; + } +} +EXPORT_SYMBOL(drm_dp_link_rate_to_bw_code); + +int drm_dp_bw_code_to_link_rate(u8 link_bw) +{ + switch (link_bw) { + case DP_LINK_BW_10: + return 1000000; + case DP_LINK_BW_13_5: + return 1350000; + case DP_LINK_BW_20: + return 2000000; + default: + /* Spec says link_rate = link_bw * 0.27Gbps */ + return link_bw * 27000; + } +} +EXPORT_SYMBOL(drm_dp_bw_code_to_link_rate); + +#define AUX_RETRY_INTERVAL 500 /* us */ + +static inline void +drm_dp_dump_access(const struct drm_dp_aux *aux, + u8 request, uint offset, void *buffer, int ret) +{ + const char *arrow = request == DP_AUX_NATIVE_READ ? "->" : "<-"; + + if (ret > 0) + drm_dbg_dp(aux->drm_dev, "%s: 0x%05x AUX %s (ret=%3d) %*ph\n", + aux->name, offset, arrow, ret, min(ret, 20), buffer); + else + drm_dbg_dp(aux->drm_dev, "%s: 0x%05x AUX %s (ret=%3d)\n", + aux->name, offset, arrow, ret); +} + +/** + * DOC: dp helpers + * + * The DisplayPort AUX channel is an abstraction to allow generic, driver- + * independent access to AUX functionality. Drivers can take advantage of + * this by filling in the fields of the drm_dp_aux structure. + * + * Transactions are described using a hardware-independent drm_dp_aux_msg + * structure, which is passed into a driver's .transfer() implementation. + * Both native and I2C-over-AUX transactions are supported. + */ + +static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8 request, + unsigned int offset, void *buffer, size_t size) +{ + struct drm_dp_aux_msg msg; + unsigned int retry, native_reply; + int err = 0, ret = 0; + + memset(&msg, 0, sizeof(msg)); + msg.address = offset; + msg.request = request; + msg.buffer = buffer; + msg.size = size; + + mutex_lock(&aux->hw_mutex); + + /* + * The specification doesn't give any recommendation on how often to + * retry native transactions. We used to retry 7 times like for + * aux i2c transactions but real world devices this wasn't + * sufficient, bump to 32 which makes Dell 4k monitors happier. + */ + for (retry = 0; retry < 32; retry++) { + if (ret != 0 && ret != -ETIMEDOUT) { + usleep_range(AUX_RETRY_INTERVAL, + AUX_RETRY_INTERVAL + 100); + } + + ret = aux->transfer(aux, &msg); + if (ret >= 0) { + native_reply = msg.reply & DP_AUX_NATIVE_REPLY_MASK; + if (native_reply == DP_AUX_NATIVE_REPLY_ACK) { + if (ret == size) + goto unlock; + + ret = -EPROTO; + } else + ret = -EIO; + } + + /* + * We want the error we return to be the error we received on + * the first transaction, since we may get a different error the + * next time we retry + */ + if (!err) + err = ret; + } + + drm_dbg_kms(aux->drm_dev, "%s: Too many retries, giving up. First error: %d\n", + aux->name, err); + ret = err; + +unlock: + mutex_unlock(&aux->hw_mutex); + return ret; +} + +/** + * drm_dp_dpcd_probe() - probe a given DPCD address with a 1-byte read access + * @aux: DisplayPort AUX channel (SST) + * @offset: address of the register to probe + * + * Probe the provided DPCD address by reading 1 byte from it. The function can + * be used to trigger some side-effect the read access has, like waking up the + * sink, without the need for the read-out value. + * + * Returns 0 if the read access suceeded, or a negative error code on failure. + */ +int drm_dp_dpcd_probe(struct drm_dp_aux *aux, unsigned int offset) +{ + u8 buffer; + int ret; + + ret = drm_dp_dpcd_access(aux, DP_AUX_NATIVE_READ, offset, &buffer, 1); + WARN_ON(ret == 0); + + drm_dp_dump_access(aux, DP_AUX_NATIVE_READ, offset, &buffer, ret); + + return ret < 0 ? ret : 0; +} +EXPORT_SYMBOL(drm_dp_dpcd_probe); + +/** + * drm_dp_dpcd_read() - read a series of bytes from the DPCD + * @aux: DisplayPort AUX channel (SST or MST) + * @offset: address of the (first) register to read + * @buffer: buffer to store the register values + * @size: number of bytes in @buffer + * + * Returns the number of bytes transferred on success, or a negative error + * code on failure. -EIO is returned if the request was NAKed by the sink or + * if the retry count was exceeded. If not all bytes were transferred, this + * function returns -EPROTO. Errors from the underlying AUX channel transfer + * function, with the exception of -EBUSY (which causes the transaction to + * be retried), are propagated to the caller. + */ +ssize_t drm_dp_dpcd_read(struct drm_dp_aux *aux, unsigned int offset, + void *buffer, size_t size) +{ + int ret; + + /* + * HP ZR24w corrupts the first DPCD access after entering power save + * mode. Eg. on a read, the entire buffer will be filled with the same + * byte. Do a throw away read to avoid corrupting anything we care + * about. Afterwards things will work correctly until the monitor + * gets woken up and subsequently re-enters power save mode. + * + * The user pressing any button on the monitor is enough to wake it + * up, so there is no particularly good place to do the workaround. + * We just have to do it before any DPCD access and hope that the + * monitor doesn't power down exactly after the throw away read. + */ + if (!aux->is_remote) { + ret = drm_dp_dpcd_probe(aux, DP_DPCD_REV); + if (ret < 0) + return ret; + } + + if (aux->is_remote) + ret = drm_dp_mst_dpcd_read(aux, offset, buffer, size); + else + ret = drm_dp_dpcd_access(aux, DP_AUX_NATIVE_READ, offset, + buffer, size); + + drm_dp_dump_access(aux, DP_AUX_NATIVE_READ, offset, buffer, ret); + return ret; +} +EXPORT_SYMBOL(drm_dp_dpcd_read); + +/** + * drm_dp_dpcd_write() - write a series of bytes to the DPCD + * @aux: DisplayPort AUX channel (SST or MST) + * @offset: address of the (first) register to write + * @buffer: buffer containing the values to write + * @size: number of bytes in @buffer + * + * Returns the number of bytes transferred on success, or a negative error + * code on failure. -EIO is returned if the request was NAKed by the sink or + * if the retry count was exceeded. If not all bytes were transferred, this + * function returns -EPROTO. Errors from the underlying AUX channel transfer + * function, with the exception of -EBUSY (which causes the transaction to + * be retried), are propagated to the caller. + */ +ssize_t drm_dp_dpcd_write(struct drm_dp_aux *aux, unsigned int offset, + void *buffer, size_t size) +{ + int ret; + + if (aux->is_remote) + ret = drm_dp_mst_dpcd_write(aux, offset, buffer, size); + else + ret = drm_dp_dpcd_access(aux, DP_AUX_NATIVE_WRITE, offset, + buffer, size); + + drm_dp_dump_access(aux, DP_AUX_NATIVE_WRITE, offset, buffer, ret); + return ret; +} +EXPORT_SYMBOL(drm_dp_dpcd_write); + +/** + * drm_dp_dpcd_read_link_status() - read DPCD link status (bytes 0x202-0x207) + * @aux: DisplayPort AUX channel + * @status: buffer to store the link status in (must be at least 6 bytes) + * + * Returns the number of bytes transferred on success or a negative error + * code on failure. + */ +int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux, + u8 status[DP_LINK_STATUS_SIZE]) +{ + return drm_dp_dpcd_read(aux, DP_LANE0_1_STATUS, status, + DP_LINK_STATUS_SIZE); +} +EXPORT_SYMBOL(drm_dp_dpcd_read_link_status); + +/** + * drm_dp_dpcd_read_phy_link_status - get the link status information for a DP PHY + * @aux: DisplayPort AUX channel + * @dp_phy: the DP PHY to get the link status for + * @link_status: buffer to return the status in + * + * Fetch the AUX DPCD registers for the DPRX or an LTTPR PHY link status. The + * layout of the returned @link_status matches the DPCD register layout of the + * DPRX PHY link status. + * + * Returns 0 if the information was read successfully or a negative error code + * on failure. + */ +int drm_dp_dpcd_read_phy_link_status(struct drm_dp_aux *aux, + enum drm_dp_phy dp_phy, + u8 link_status[DP_LINK_STATUS_SIZE]) +{ + int ret; + + if (dp_phy == DP_PHY_DPRX) { + ret = drm_dp_dpcd_read(aux, + DP_LANE0_1_STATUS, + link_status, + DP_LINK_STATUS_SIZE); + + if (ret < 0) + return ret; + + WARN_ON(ret != DP_LINK_STATUS_SIZE); + + return 0; + } + + ret = drm_dp_dpcd_read(aux, + DP_LANE0_1_STATUS_PHY_REPEATER(dp_phy), + link_status, + DP_LINK_STATUS_SIZE - 1); + + if (ret < 0) + return ret; + + WARN_ON(ret != DP_LINK_STATUS_SIZE - 1); + + /* Convert the LTTPR to the sink PHY link status layout */ + memmove(&link_status[DP_SINK_STATUS - DP_LANE0_1_STATUS + 1], + &link_status[DP_SINK_STATUS - DP_LANE0_1_STATUS], + DP_LINK_STATUS_SIZE - (DP_SINK_STATUS - DP_LANE0_1_STATUS) - 1); + link_status[DP_SINK_STATUS - DP_LANE0_1_STATUS] = 0; + + return 0; +} +EXPORT_SYMBOL(drm_dp_dpcd_read_phy_link_status); + +static bool is_edid_digital_input_dp(const struct edid *edid) +{ + return edid && edid->revision >= 4 && + edid->input & DRM_EDID_INPUT_DIGITAL && + (edid->input & DRM_EDID_DIGITAL_TYPE_MASK) == DRM_EDID_DIGITAL_TYPE_DP; +} + +/** + * drm_dp_downstream_is_type() - is the downstream facing port of certain type? + * @dpcd: DisplayPort configuration data + * @port_cap: port capabilities + * @type: port type to be checked. Can be: + * %DP_DS_PORT_TYPE_DP, %DP_DS_PORT_TYPE_VGA, %DP_DS_PORT_TYPE_DVI, + * %DP_DS_PORT_TYPE_HDMI, %DP_DS_PORT_TYPE_NON_EDID, + * %DP_DS_PORT_TYPE_DP_DUALMODE or %DP_DS_PORT_TYPE_WIRELESS. + * + * Caveat: Only works with DPCD 1.1+ port caps. + * + * Returns: whether the downstream facing port matches the type. + */ +bool drm_dp_downstream_is_type(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4], u8 type) +{ + return drm_dp_is_branch(dpcd) && + dpcd[DP_DPCD_REV] >= 0x11 && + (port_cap[0] & DP_DS_PORT_TYPE_MASK) == type; +} +EXPORT_SYMBOL(drm_dp_downstream_is_type); + +/** + * drm_dp_downstream_is_tmds() - is the downstream facing port TMDS? + * @dpcd: DisplayPort configuration data + * @port_cap: port capabilities + * @edid: EDID + * + * Returns: whether the downstream facing port is TMDS (HDMI/DVI). + */ +bool drm_dp_downstream_is_tmds(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4], + const struct edid *edid) +{ + if (dpcd[DP_DPCD_REV] < 0x11) { + switch (dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_TYPE_MASK) { + case DP_DWN_STRM_PORT_TYPE_TMDS: + return true; + default: + return false; + } + } + + switch (port_cap[0] & DP_DS_PORT_TYPE_MASK) { + case DP_DS_PORT_TYPE_DP_DUALMODE: + if (is_edid_digital_input_dp(edid)) + return false; + fallthrough; + case DP_DS_PORT_TYPE_DVI: + case DP_DS_PORT_TYPE_HDMI: + return true; + default: + return false; + } +} +EXPORT_SYMBOL(drm_dp_downstream_is_tmds); + +/** + * drm_dp_send_real_edid_checksum() - send back real edid checksum value + * @aux: DisplayPort AUX channel + * @real_edid_checksum: real edid checksum for the last block + * + * Returns: + * True on success + */ +bool drm_dp_send_real_edid_checksum(struct drm_dp_aux *aux, + u8 real_edid_checksum) +{ + u8 link_edid_read = 0, auto_test_req = 0, test_resp = 0; + + if (drm_dp_dpcd_read(aux, DP_DEVICE_SERVICE_IRQ_VECTOR, + &auto_test_req, 1) < 1) { + drm_err(aux->drm_dev, "%s: DPCD failed read at register 0x%x\n", + aux->name, DP_DEVICE_SERVICE_IRQ_VECTOR); + return false; + } + auto_test_req &= DP_AUTOMATED_TEST_REQUEST; + + if (drm_dp_dpcd_read(aux, DP_TEST_REQUEST, &link_edid_read, 1) < 1) { + drm_err(aux->drm_dev, "%s: DPCD failed read at register 0x%x\n", + aux->name, DP_TEST_REQUEST); + return false; + } + link_edid_read &= DP_TEST_LINK_EDID_READ; + + if (!auto_test_req || !link_edid_read) { + drm_dbg_kms(aux->drm_dev, "%s: Source DUT does not support TEST_EDID_READ\n", + aux->name); + return false; + } + + if (drm_dp_dpcd_write(aux, DP_DEVICE_SERVICE_IRQ_VECTOR, + &auto_test_req, 1) < 1) { + drm_err(aux->drm_dev, "%s: DPCD failed write at register 0x%x\n", + aux->name, DP_DEVICE_SERVICE_IRQ_VECTOR); + return false; + } + + /* send back checksum for the last edid extension block data */ + if (drm_dp_dpcd_write(aux, DP_TEST_EDID_CHECKSUM, + &real_edid_checksum, 1) < 1) { + drm_err(aux->drm_dev, "%s: DPCD failed write at register 0x%x\n", + aux->name, DP_TEST_EDID_CHECKSUM); + return false; + } + + test_resp |= DP_TEST_EDID_CHECKSUM_WRITE; + if (drm_dp_dpcd_write(aux, DP_TEST_RESPONSE, &test_resp, 1) < 1) { + drm_err(aux->drm_dev, "%s: DPCD failed write at register 0x%x\n", + aux->name, DP_TEST_RESPONSE); + return false; + } + + return true; +} +EXPORT_SYMBOL(drm_dp_send_real_edid_checksum); + +static u8 drm_dp_downstream_port_count(const u8 dpcd[DP_RECEIVER_CAP_SIZE]) +{ + u8 port_count = dpcd[DP_DOWN_STREAM_PORT_COUNT] & DP_PORT_COUNT_MASK; + + if (dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DETAILED_CAP_INFO_AVAILABLE && port_count > 4) + port_count = 4; + + return port_count; +} + +static int drm_dp_read_extended_dpcd_caps(struct drm_dp_aux *aux, + u8 dpcd[DP_RECEIVER_CAP_SIZE]) +{ + u8 dpcd_ext[DP_RECEIVER_CAP_SIZE]; + int ret; + + /* + * Prior to DP1.3 the bit represented by + * DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT was reserved. + * If it is set DP_DPCD_REV at 0000h could be at a value less than + * the true capability of the panel. The only way to check is to + * then compare 0000h and 2200h. + */ + if (!(dpcd[DP_TRAINING_AUX_RD_INTERVAL] & + DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT)) + return 0; + + ret = drm_dp_dpcd_read(aux, DP_DP13_DPCD_REV, &dpcd_ext, + sizeof(dpcd_ext)); + if (ret < 0) + return ret; + if (ret != sizeof(dpcd_ext)) + return -EIO; + + if (dpcd[DP_DPCD_REV] > dpcd_ext[DP_DPCD_REV]) { + drm_dbg_kms(aux->drm_dev, + "%s: Extended DPCD rev less than base DPCD rev (%d > %d)\n", + aux->name, dpcd[DP_DPCD_REV], dpcd_ext[DP_DPCD_REV]); + return 0; + } + + if (!memcmp(dpcd, dpcd_ext, sizeof(dpcd_ext))) + return 0; + + drm_dbg_kms(aux->drm_dev, "%s: Base DPCD: %*ph\n", aux->name, DP_RECEIVER_CAP_SIZE, dpcd); + + memcpy(dpcd, dpcd_ext, sizeof(dpcd_ext)); + + return 0; +} + +/** + * drm_dp_read_dpcd_caps() - read DPCD caps and extended DPCD caps if + * available + * @aux: DisplayPort AUX channel + * @dpcd: Buffer to store the resulting DPCD in + * + * Attempts to read the base DPCD caps for @aux. Additionally, this function + * checks for and reads the extended DPRX caps (%DP_DP13_DPCD_REV) if + * present. + * + * Returns: %0 if the DPCD was read successfully, negative error code + * otherwise. + */ +int drm_dp_read_dpcd_caps(struct drm_dp_aux *aux, + u8 dpcd[DP_RECEIVER_CAP_SIZE]) +{ + int ret; + + ret = drm_dp_dpcd_read(aux, DP_DPCD_REV, dpcd, DP_RECEIVER_CAP_SIZE); + if (ret < 0) + return ret; + if (ret != DP_RECEIVER_CAP_SIZE || dpcd[DP_DPCD_REV] == 0) + return -EIO; + + ret = drm_dp_read_extended_dpcd_caps(aux, dpcd); + if (ret < 0) + return ret; + + drm_dbg_kms(aux->drm_dev, "%s: DPCD: %*ph\n", aux->name, DP_RECEIVER_CAP_SIZE, dpcd); + + return ret; +} +EXPORT_SYMBOL(drm_dp_read_dpcd_caps); + +/** + * drm_dp_read_downstream_info() - read DPCD downstream port info if available + * @aux: DisplayPort AUX channel + * @dpcd: A cached copy of the port's DPCD + * @downstream_ports: buffer to store the downstream port info in + * + * See also: + * drm_dp_downstream_max_clock() + * drm_dp_downstream_max_bpc() + * + * Returns: 0 if either the downstream port info was read successfully or + * there was no downstream info to read, or a negative error code otherwise. + */ +int drm_dp_read_downstream_info(struct drm_dp_aux *aux, + const u8 dpcd[DP_RECEIVER_CAP_SIZE], + u8 downstream_ports[DP_MAX_DOWNSTREAM_PORTS]) +{ + int ret; + u8 len; + + memset(downstream_ports, 0, DP_MAX_DOWNSTREAM_PORTS); + + /* No downstream info to read */ + if (!drm_dp_is_branch(dpcd) || dpcd[DP_DPCD_REV] == DP_DPCD_REV_10) + return 0; + + /* Some branches advertise having 0 downstream ports, despite also advertising they have a + * downstream port present. The DP spec isn't clear on if this is allowed or not, but since + * some branches do it we need to handle it regardless. + */ + len = drm_dp_downstream_port_count(dpcd); + if (!len) + return 0; + + if (dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DETAILED_CAP_INFO_AVAILABLE) + len *= 4; + + ret = drm_dp_dpcd_read(aux, DP_DOWNSTREAM_PORT_0, downstream_ports, len); + if (ret < 0) + return ret; + if (ret != len) + return -EIO; + + drm_dbg_kms(aux->drm_dev, "%s: DPCD DFP: %*ph\n", aux->name, len, downstream_ports); + + return 0; +} +EXPORT_SYMBOL(drm_dp_read_downstream_info); + +/** + * drm_dp_downstream_max_dotclock() - extract downstream facing port max dot clock + * @dpcd: DisplayPort configuration data + * @port_cap: port capabilities + * + * Returns: Downstream facing port max dot clock in kHz on success, + * or 0 if max clock not defined + */ +int drm_dp_downstream_max_dotclock(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4]) +{ + if (!drm_dp_is_branch(dpcd)) + return 0; + + if (dpcd[DP_DPCD_REV] < 0x11) + return 0; + + switch (port_cap[0] & DP_DS_PORT_TYPE_MASK) { + case DP_DS_PORT_TYPE_VGA: + if ((dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DETAILED_CAP_INFO_AVAILABLE) == 0) + return 0; + return port_cap[1] * 8000; + default: + return 0; + } +} +EXPORT_SYMBOL(drm_dp_downstream_max_dotclock); + +/** + * drm_dp_downstream_max_tmds_clock() - extract downstream facing port max TMDS clock + * @dpcd: DisplayPort configuration data + * @port_cap: port capabilities + * @edid: EDID + * + * Returns: HDMI/DVI downstream facing port max TMDS clock in kHz on success, + * or 0 if max TMDS clock not defined + */ +int drm_dp_downstream_max_tmds_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4], + const struct edid *edid) +{ + if (!drm_dp_is_branch(dpcd)) + return 0; + + if (dpcd[DP_DPCD_REV] < 0x11) { + switch (dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_TYPE_MASK) { + case DP_DWN_STRM_PORT_TYPE_TMDS: + return 165000; + default: + return 0; + } + } + + switch (port_cap[0] & DP_DS_PORT_TYPE_MASK) { + case DP_DS_PORT_TYPE_DP_DUALMODE: + if (is_edid_digital_input_dp(edid)) + return 0; + /* + * It's left up to the driver to check the + * DP dual mode adapter's max TMDS clock. + * + * Unfortunately it looks like branch devices + * may not fordward that the DP dual mode i2c + * access so we just usually get i2c nak :( + */ + fallthrough; + case DP_DS_PORT_TYPE_HDMI: + /* + * We should perhaps assume 165 MHz when detailed cap + * info is not available. But looks like many typical + * branch devices fall into that category and so we'd + * probably end up with users complaining that they can't + * get high resolution modes with their favorite dongle. + * + * So let's limit to 300 MHz instead since DPCD 1.4 + * HDMI 2.0 DFPs are required to have the detailed cap + * info. So it's more likely we're dealing with a HDMI 1.4 + * compatible* device here. + */ + if ((dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DETAILED_CAP_INFO_AVAILABLE) == 0) + return 300000; + return port_cap[1] * 2500; + case DP_DS_PORT_TYPE_DVI: + if ((dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DETAILED_CAP_INFO_AVAILABLE) == 0) + return 165000; + /* FIXME what to do about DVI dual link? */ + return port_cap[1] * 2500; + default: + return 0; + } +} +EXPORT_SYMBOL(drm_dp_downstream_max_tmds_clock); + +/** + * drm_dp_downstream_min_tmds_clock() - extract downstream facing port min TMDS clock + * @dpcd: DisplayPort configuration data + * @port_cap: port capabilities + * @edid: EDID + * + * Returns: HDMI/DVI downstream facing port min TMDS clock in kHz on success, + * or 0 if max TMDS clock not defined + */ +int drm_dp_downstream_min_tmds_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4], + const struct edid *edid) +{ + if (!drm_dp_is_branch(dpcd)) + return 0; + + if (dpcd[DP_DPCD_REV] < 0x11) { + switch (dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_TYPE_MASK) { + case DP_DWN_STRM_PORT_TYPE_TMDS: + return 25000; + default: + return 0; + } + } + + switch (port_cap[0] & DP_DS_PORT_TYPE_MASK) { + case DP_DS_PORT_TYPE_DP_DUALMODE: + if (is_edid_digital_input_dp(edid)) + return 0; + fallthrough; + case DP_DS_PORT_TYPE_DVI: + case DP_DS_PORT_TYPE_HDMI: + /* + * Unclear whether the protocol converter could + * utilize pixel replication. Assume it won't. + */ + return 25000; + default: + return 0; + } +} +EXPORT_SYMBOL(drm_dp_downstream_min_tmds_clock); + +/** + * drm_dp_downstream_max_bpc() - extract downstream facing port max + * bits per component + * @dpcd: DisplayPort configuration data + * @port_cap: downstream facing port capabilities + * @edid: EDID + * + * Returns: Max bpc on success or 0 if max bpc not defined + */ +int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4], + const struct edid *edid) +{ + if (!drm_dp_is_branch(dpcd)) + return 0; + + if (dpcd[DP_DPCD_REV] < 0x11) { + switch (dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_TYPE_MASK) { + case DP_DWN_STRM_PORT_TYPE_DP: + return 0; + default: + return 8; + } + } + + switch (port_cap[0] & DP_DS_PORT_TYPE_MASK) { + case DP_DS_PORT_TYPE_DP: + return 0; + case DP_DS_PORT_TYPE_DP_DUALMODE: + if (is_edid_digital_input_dp(edid)) + return 0; + fallthrough; + case DP_DS_PORT_TYPE_HDMI: + case DP_DS_PORT_TYPE_DVI: + case DP_DS_PORT_TYPE_VGA: + if ((dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DETAILED_CAP_INFO_AVAILABLE) == 0) + return 8; + + switch (port_cap[2] & DP_DS_MAX_BPC_MASK) { + case DP_DS_8BPC: + return 8; + case DP_DS_10BPC: + return 10; + case DP_DS_12BPC: + return 12; + case DP_DS_16BPC: + return 16; + default: + return 8; + } + break; + default: + return 8; + } +} +EXPORT_SYMBOL(drm_dp_downstream_max_bpc); + +/** + * drm_dp_downstream_420_passthrough() - determine downstream facing port + * YCbCr 4:2:0 pass-through capability + * @dpcd: DisplayPort configuration data + * @port_cap: downstream facing port capabilities + * + * Returns: whether the downstream facing port can pass through YCbCr 4:2:0 + */ +bool drm_dp_downstream_420_passthrough(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4]) +{ + if (!drm_dp_is_branch(dpcd)) + return false; + + if (dpcd[DP_DPCD_REV] < 0x13) + return false; + + switch (port_cap[0] & DP_DS_PORT_TYPE_MASK) { + case DP_DS_PORT_TYPE_DP: + return true; + case DP_DS_PORT_TYPE_HDMI: + if ((dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DETAILED_CAP_INFO_AVAILABLE) == 0) + return false; + + return port_cap[3] & DP_DS_HDMI_YCBCR420_PASS_THROUGH; + default: + return false; + } +} +EXPORT_SYMBOL(drm_dp_downstream_420_passthrough); + +/** + * drm_dp_downstream_444_to_420_conversion() - determine downstream facing port + * YCbCr 4:4:4->4:2:0 conversion capability + * @dpcd: DisplayPort configuration data + * @port_cap: downstream facing port capabilities + * + * Returns: whether the downstream facing port can convert YCbCr 4:4:4 to 4:2:0 + */ +bool drm_dp_downstream_444_to_420_conversion(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4]) +{ + if (!drm_dp_is_branch(dpcd)) + return false; + + if (dpcd[DP_DPCD_REV] < 0x13) + return false; + + switch (port_cap[0] & DP_DS_PORT_TYPE_MASK) { + case DP_DS_PORT_TYPE_HDMI: + if ((dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DETAILED_CAP_INFO_AVAILABLE) == 0) + return false; + + return port_cap[3] & DP_DS_HDMI_YCBCR444_TO_420_CONV; + default: + return false; + } +} +EXPORT_SYMBOL(drm_dp_downstream_444_to_420_conversion); + +/** + * drm_dp_downstream_rgb_to_ycbcr_conversion() - determine downstream facing port + * RGB->YCbCr conversion capability + * @dpcd: DisplayPort configuration data + * @port_cap: downstream facing port capabilities + * @color_spc: Colorspace for which conversion cap is sought + * + * Returns: whether the downstream facing port can convert RGB->YCbCr for a given + * colorspace. + */ +bool drm_dp_downstream_rgb_to_ycbcr_conversion(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4], + u8 color_spc) +{ + if (!drm_dp_is_branch(dpcd)) + return false; + + if (dpcd[DP_DPCD_REV] < 0x13) + return false; + + switch (port_cap[0] & DP_DS_PORT_TYPE_MASK) { + case DP_DS_PORT_TYPE_HDMI: + if ((dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DETAILED_CAP_INFO_AVAILABLE) == 0) + return false; + + return port_cap[3] & color_spc; + default: + return false; + } +} +EXPORT_SYMBOL(drm_dp_downstream_rgb_to_ycbcr_conversion); + +/** + * drm_dp_downstream_mode() - return a mode for downstream facing port + * @dev: DRM device + * @dpcd: DisplayPort configuration data + * @port_cap: port capabilities + * + * Provides a suitable mode for downstream facing ports without EDID. + * + * Returns: A new drm_display_mode on success or NULL on failure + */ +struct drm_display_mode * +drm_dp_downstream_mode(struct drm_device *dev, + const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4]) + +{ + u8 vic; + + if (!drm_dp_is_branch(dpcd)) + return NULL; + + if (dpcd[DP_DPCD_REV] < 0x11) + return NULL; + + switch (port_cap[0] & DP_DS_PORT_TYPE_MASK) { + case DP_DS_PORT_TYPE_NON_EDID: + switch (port_cap[0] & DP_DS_NON_EDID_MASK) { + case DP_DS_NON_EDID_720x480i_60: + vic = 6; + break; + case DP_DS_NON_EDID_720x480i_50: + vic = 21; + break; + case DP_DS_NON_EDID_1920x1080i_60: + vic = 5; + break; + case DP_DS_NON_EDID_1920x1080i_50: + vic = 20; + break; + case DP_DS_NON_EDID_1280x720_60: + vic = 4; + break; + case DP_DS_NON_EDID_1280x720_50: + vic = 19; + break; + default: + return NULL; + } + return drm_display_mode_from_cea_vic(dev, vic); + default: + return NULL; + } +} +EXPORT_SYMBOL(drm_dp_downstream_mode); + +/** + * drm_dp_downstream_id() - identify branch device + * @aux: DisplayPort AUX channel + * @id: DisplayPort branch device id + * + * Returns branch device id on success or NULL on failure + */ +int drm_dp_downstream_id(struct drm_dp_aux *aux, char id[6]) +{ + return drm_dp_dpcd_read(aux, DP_BRANCH_ID, id, 6); +} +EXPORT_SYMBOL(drm_dp_downstream_id); + +/** + * drm_dp_downstream_debug() - debug DP branch devices + * @m: pointer for debugfs file + * @dpcd: DisplayPort configuration data + * @port_cap: port capabilities + * @edid: EDID + * @aux: DisplayPort AUX channel + * + */ +void drm_dp_downstream_debug(struct seq_file *m, + const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4], + const struct edid *edid, + struct drm_dp_aux *aux) +{ + bool detailed_cap_info = dpcd[DP_DOWNSTREAMPORT_PRESENT] & + DP_DETAILED_CAP_INFO_AVAILABLE; + int clk; + int bpc; + char id[7]; + int len; + uint8_t rev[2]; + int type = port_cap[0] & DP_DS_PORT_TYPE_MASK; + bool branch_device = drm_dp_is_branch(dpcd); + + seq_printf(m, "\tDP branch device present: %s\n", + str_yes_no(branch_device)); + + if (!branch_device) + return; + + switch (type) { + case DP_DS_PORT_TYPE_DP: + seq_puts(m, "\t\tType: DisplayPort\n"); + break; + case DP_DS_PORT_TYPE_VGA: + seq_puts(m, "\t\tType: VGA\n"); + break; + case DP_DS_PORT_TYPE_DVI: + seq_puts(m, "\t\tType: DVI\n"); + break; + case DP_DS_PORT_TYPE_HDMI: + seq_puts(m, "\t\tType: HDMI\n"); + break; + case DP_DS_PORT_TYPE_NON_EDID: + seq_puts(m, "\t\tType: others without EDID support\n"); + break; + case DP_DS_PORT_TYPE_DP_DUALMODE: + seq_puts(m, "\t\tType: DP++\n"); + break; + case DP_DS_PORT_TYPE_WIRELESS: + seq_puts(m, "\t\tType: Wireless\n"); + break; + default: + seq_puts(m, "\t\tType: N/A\n"); + } + + memset(id, 0, sizeof(id)); + drm_dp_downstream_id(aux, id); + seq_printf(m, "\t\tID: %s\n", id); + + len = drm_dp_dpcd_read(aux, DP_BRANCH_HW_REV, &rev[0], 1); + if (len > 0) + seq_printf(m, "\t\tHW: %d.%d\n", + (rev[0] & 0xf0) >> 4, rev[0] & 0xf); + + len = drm_dp_dpcd_read(aux, DP_BRANCH_SW_REV, rev, 2); + if (len > 0) + seq_printf(m, "\t\tSW: %d.%d\n", rev[0], rev[1]); + + if (detailed_cap_info) { + clk = drm_dp_downstream_max_dotclock(dpcd, port_cap); + if (clk > 0) + seq_printf(m, "\t\tMax dot clock: %d kHz\n", clk); + + clk = drm_dp_downstream_max_tmds_clock(dpcd, port_cap, edid); + if (clk > 0) + seq_printf(m, "\t\tMax TMDS clock: %d kHz\n", clk); + + clk = drm_dp_downstream_min_tmds_clock(dpcd, port_cap, edid); + if (clk > 0) + seq_printf(m, "\t\tMin TMDS clock: %d kHz\n", clk); + + bpc = drm_dp_downstream_max_bpc(dpcd, port_cap, edid); + + if (bpc > 0) + seq_printf(m, "\t\tMax bpc: %d\n", bpc); + } +} +EXPORT_SYMBOL(drm_dp_downstream_debug); + +/** + * drm_dp_subconnector_type() - get DP branch device type + * @dpcd: DisplayPort configuration data + * @port_cap: port capabilities + */ +enum drm_mode_subconnector +drm_dp_subconnector_type(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4]) +{ + int type; + if (!drm_dp_is_branch(dpcd)) + return DRM_MODE_SUBCONNECTOR_Native; + /* DP 1.0 approach */ + if (dpcd[DP_DPCD_REV] == DP_DPCD_REV_10) { + type = dpcd[DP_DOWNSTREAMPORT_PRESENT] & + DP_DWN_STRM_PORT_TYPE_MASK; + + switch (type) { + case DP_DWN_STRM_PORT_TYPE_TMDS: + /* Can be HDMI or DVI-D, DVI-D is a safer option */ + return DRM_MODE_SUBCONNECTOR_DVID; + case DP_DWN_STRM_PORT_TYPE_ANALOG: + /* Can be VGA or DVI-A, VGA is more popular */ + return DRM_MODE_SUBCONNECTOR_VGA; + case DP_DWN_STRM_PORT_TYPE_DP: + return DRM_MODE_SUBCONNECTOR_DisplayPort; + case DP_DWN_STRM_PORT_TYPE_OTHER: + default: + return DRM_MODE_SUBCONNECTOR_Unknown; + } + } + type = port_cap[0] & DP_DS_PORT_TYPE_MASK; + + switch (type) { + case DP_DS_PORT_TYPE_DP: + case DP_DS_PORT_TYPE_DP_DUALMODE: + return DRM_MODE_SUBCONNECTOR_DisplayPort; + case DP_DS_PORT_TYPE_VGA: + return DRM_MODE_SUBCONNECTOR_VGA; + case DP_DS_PORT_TYPE_DVI: + return DRM_MODE_SUBCONNECTOR_DVID; + case DP_DS_PORT_TYPE_HDMI: + return DRM_MODE_SUBCONNECTOR_HDMIA; + case DP_DS_PORT_TYPE_WIRELESS: + return DRM_MODE_SUBCONNECTOR_Wireless; + case DP_DS_PORT_TYPE_NON_EDID: + default: + return DRM_MODE_SUBCONNECTOR_Unknown; + } +} +EXPORT_SYMBOL(drm_dp_subconnector_type); + +/** + * drm_dp_set_subconnector_property - set subconnector for DP connector + * @connector: connector to set property on + * @status: connector status + * @dpcd: DisplayPort configuration data + * @port_cap: port capabilities + * + * Called by a driver on every detect event. + */ +void drm_dp_set_subconnector_property(struct drm_connector *connector, + enum drm_connector_status status, + const u8 *dpcd, + const u8 port_cap[4]) +{ + enum drm_mode_subconnector subconnector = DRM_MODE_SUBCONNECTOR_Unknown; + + if (status == connector_status_connected) + subconnector = drm_dp_subconnector_type(dpcd, port_cap); + drm_object_property_set_value(&connector->base, + connector->dev->mode_config.dp_subconnector_property, + subconnector); +} +EXPORT_SYMBOL(drm_dp_set_subconnector_property); + +/** + * drm_dp_read_sink_count_cap() - Check whether a given connector has a valid sink + * count + * @connector: The DRM connector to check + * @dpcd: A cached copy of the connector's DPCD RX capabilities + * @desc: A cached copy of the connector's DP descriptor + * + * See also: drm_dp_read_sink_count() + * + * Returns: %True if the (e)DP connector has a valid sink count that should + * be probed, %false otherwise. + */ +bool drm_dp_read_sink_count_cap(struct drm_connector *connector, + const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const struct drm_dp_desc *desc) +{ + /* Some eDP panels don't set a valid value for the sink count */ + return connector->connector_type != DRM_MODE_CONNECTOR_eDP && + dpcd[DP_DPCD_REV] >= DP_DPCD_REV_11 && + dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_PRESENT && + !drm_dp_has_quirk(desc, DP_DPCD_QUIRK_NO_SINK_COUNT); +} +EXPORT_SYMBOL(drm_dp_read_sink_count_cap); + +/** + * drm_dp_read_sink_count() - Retrieve the sink count for a given sink + * @aux: The DP AUX channel to use + * + * See also: drm_dp_read_sink_count_cap() + * + * Returns: The current sink count reported by @aux, or a negative error code + * otherwise. + */ +int drm_dp_read_sink_count(struct drm_dp_aux *aux) +{ + u8 count; + int ret; + + ret = drm_dp_dpcd_readb(aux, DP_SINK_COUNT, &count); + if (ret < 0) + return ret; + if (ret != 1) + return -EIO; + + return DP_GET_SINK_COUNT(count); +} +EXPORT_SYMBOL(drm_dp_read_sink_count); + +/* + * I2C-over-AUX implementation + */ + +static u32 drm_dp_i2c_functionality(struct i2c_adapter *adapter) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | + I2C_FUNC_SMBUS_READ_BLOCK_DATA | + I2C_FUNC_SMBUS_BLOCK_PROC_CALL | + I2C_FUNC_10BIT_ADDR; +} + +static void drm_dp_i2c_msg_write_status_update(struct drm_dp_aux_msg *msg) +{ + /* + * In case of i2c defer or short i2c ack reply to a write, + * we need to switch to WRITE_STATUS_UPDATE to drain the + * rest of the message + */ + if ((msg->request & ~DP_AUX_I2C_MOT) == DP_AUX_I2C_WRITE) { + msg->request &= DP_AUX_I2C_MOT; + msg->request |= DP_AUX_I2C_WRITE_STATUS_UPDATE; + } +} + +#define AUX_PRECHARGE_LEN 10 /* 10 to 16 */ +#define AUX_SYNC_LEN (16 + 4) /* preamble + AUX_SYNC_END */ +#define AUX_STOP_LEN 4 +#define AUX_CMD_LEN 4 +#define AUX_ADDRESS_LEN 20 +#define AUX_REPLY_PAD_LEN 4 +#define AUX_LENGTH_LEN 8 + +/* + * Calculate the duration of the AUX request/reply in usec. Gives the + * "best" case estimate, ie. successful while as short as possible. + */ +static int drm_dp_aux_req_duration(const struct drm_dp_aux_msg *msg) +{ + int len = AUX_PRECHARGE_LEN + AUX_SYNC_LEN + AUX_STOP_LEN + + AUX_CMD_LEN + AUX_ADDRESS_LEN + AUX_LENGTH_LEN; + + if ((msg->request & DP_AUX_I2C_READ) == 0) + len += msg->size * 8; + + return len; +} + +static int drm_dp_aux_reply_duration(const struct drm_dp_aux_msg *msg) +{ + int len = AUX_PRECHARGE_LEN + AUX_SYNC_LEN + AUX_STOP_LEN + + AUX_CMD_LEN + AUX_REPLY_PAD_LEN; + + /* + * For read we expect what was asked. For writes there will + * be 0 or 1 data bytes. Assume 0 for the "best" case. + */ + if (msg->request & DP_AUX_I2C_READ) + len += msg->size * 8; + + return len; +} + +#define I2C_START_LEN 1 +#define I2C_STOP_LEN 1 +#define I2C_ADDR_LEN 9 /* ADDRESS + R/W + ACK/NACK */ +#define I2C_DATA_LEN 9 /* DATA + ACK/NACK */ + +/* + * Calculate the length of the i2c transfer in usec, assuming + * the i2c bus speed is as specified. Gives the "worst" + * case estimate, ie. successful while as long as possible. + * Doesn't account the "MOT" bit, and instead assumes each + * message includes a START, ADDRESS and STOP. Neither does it + * account for additional random variables such as clock stretching. + */ +static int drm_dp_i2c_msg_duration(const struct drm_dp_aux_msg *msg, + int i2c_speed_khz) +{ + /* AUX bitrate is 1MHz, i2c bitrate as specified */ + return DIV_ROUND_UP((I2C_START_LEN + I2C_ADDR_LEN + + msg->size * I2C_DATA_LEN + + I2C_STOP_LEN) * 1000, i2c_speed_khz); +} + +/* + * Determine how many retries should be attempted to successfully transfer + * the specified message, based on the estimated durations of the + * i2c and AUX transfers. + */ +static int drm_dp_i2c_retry_count(const struct drm_dp_aux_msg *msg, + int i2c_speed_khz) +{ + int aux_time_us = drm_dp_aux_req_duration(msg) + + drm_dp_aux_reply_duration(msg); + int i2c_time_us = drm_dp_i2c_msg_duration(msg, i2c_speed_khz); + + return DIV_ROUND_UP(i2c_time_us, aux_time_us + AUX_RETRY_INTERVAL); +} + +/* + * FIXME currently assumes 10 kHz as some real world devices seem + * to require it. We should query/set the speed via DPCD if supported. + */ +static int dp_aux_i2c_speed_khz __read_mostly = 10; +module_param_unsafe(dp_aux_i2c_speed_khz, int, 0644); +MODULE_PARM_DESC(dp_aux_i2c_speed_khz, + "Assumed speed of the i2c bus in kHz, (1-400, default 10)"); + +/* + * Transfer a single I2C-over-AUX message and handle various error conditions, + * retrying the transaction as appropriate. It is assumed that the + * &drm_dp_aux.transfer function does not modify anything in the msg other than the + * reply field. + * + * Returns bytes transferred on success, or a negative error code on failure. + */ +static int drm_dp_i2c_do_msg(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) +{ + unsigned int retry, defer_i2c; + int ret; + /* + * DP1.2 sections 2.7.7.1.5.6.1 and 2.7.7.1.6.6.1: A DP Source device + * is required to retry at least seven times upon receiving AUX_DEFER + * before giving up the AUX transaction. + * + * We also try to account for the i2c bus speed. + */ + int max_retries = max(7, drm_dp_i2c_retry_count(msg, dp_aux_i2c_speed_khz)); + + for (retry = 0, defer_i2c = 0; retry < (max_retries + defer_i2c); retry++) { + ret = aux->transfer(aux, msg); + if (ret < 0) { + if (ret == -EBUSY) + continue; + + /* + * While timeouts can be errors, they're usually normal + * behavior (for instance, when a driver tries to + * communicate with a non-existent DisplayPort device). + * Avoid spamming the kernel log with timeout errors. + */ + if (ret == -ETIMEDOUT) + drm_dbg_kms_ratelimited(aux->drm_dev, "%s: transaction timed out\n", + aux->name); + else + drm_dbg_kms(aux->drm_dev, "%s: transaction failed: %d\n", + aux->name, ret); + return ret; + } + + + switch (msg->reply & DP_AUX_NATIVE_REPLY_MASK) { + case DP_AUX_NATIVE_REPLY_ACK: + /* + * For I2C-over-AUX transactions this isn't enough, we + * need to check for the I2C ACK reply. + */ + break; + + case DP_AUX_NATIVE_REPLY_NACK: + drm_dbg_kms(aux->drm_dev, "%s: native nack (result=%d, size=%zu)\n", + aux->name, ret, msg->size); + return -EREMOTEIO; + + case DP_AUX_NATIVE_REPLY_DEFER: + drm_dbg_kms(aux->drm_dev, "%s: native defer\n", aux->name); + /* + * We could check for I2C bit rate capabilities and if + * available adjust this interval. We could also be + * more careful with DP-to-legacy adapters where a + * long legacy cable may force very low I2C bit rates. + * + * For now just defer for long enough to hopefully be + * safe for all use-cases. + */ + usleep_range(AUX_RETRY_INTERVAL, AUX_RETRY_INTERVAL + 100); + continue; + + default: + drm_err(aux->drm_dev, "%s: invalid native reply %#04x\n", + aux->name, msg->reply); + return -EREMOTEIO; + } + + switch (msg->reply & DP_AUX_I2C_REPLY_MASK) { + case DP_AUX_I2C_REPLY_ACK: + /* + * Both native ACK and I2C ACK replies received. We + * can assume the transfer was successful. + */ + if (ret != msg->size) + drm_dp_i2c_msg_write_status_update(msg); + return ret; + + case DP_AUX_I2C_REPLY_NACK: + drm_dbg_kms(aux->drm_dev, "%s: I2C nack (result=%d, size=%zu)\n", + aux->name, ret, msg->size); + aux->i2c_nack_count++; + return -EREMOTEIO; + + case DP_AUX_I2C_REPLY_DEFER: + drm_dbg_kms(aux->drm_dev, "%s: I2C defer\n", aux->name); + /* DP Compliance Test 4.2.2.5 Requirement: + * Must have at least 7 retries for I2C defers on the + * transaction to pass this test + */ + aux->i2c_defer_count++; + if (defer_i2c < 7) + defer_i2c++; + usleep_range(AUX_RETRY_INTERVAL, AUX_RETRY_INTERVAL + 100); + drm_dp_i2c_msg_write_status_update(msg); + + continue; + + default: + drm_err(aux->drm_dev, "%s: invalid I2C reply %#04x\n", + aux->name, msg->reply); + return -EREMOTEIO; + } + } + + drm_dbg_kms(aux->drm_dev, "%s: Too many retries, giving up\n", aux->name); + return -EREMOTEIO; +} + +static void drm_dp_i2c_msg_set_request(struct drm_dp_aux_msg *msg, + const struct i2c_msg *i2c_msg) +{ + msg->request = (i2c_msg->flags & I2C_M_RD) ? + DP_AUX_I2C_READ : DP_AUX_I2C_WRITE; + if (!(i2c_msg->flags & I2C_M_STOP)) + msg->request |= DP_AUX_I2C_MOT; +} + +/* + * Keep retrying drm_dp_i2c_do_msg until all data has been transferred. + * + * Returns an error code on failure, or a recommended transfer size on success. + */ +static int drm_dp_i2c_drain_msg(struct drm_dp_aux *aux, struct drm_dp_aux_msg *orig_msg) +{ + int err, ret = orig_msg->size; + struct drm_dp_aux_msg msg = *orig_msg; + + while (msg.size > 0) { + err = drm_dp_i2c_do_msg(aux, &msg); + if (err <= 0) + return err == 0 ? -EPROTO : err; + + if (err < msg.size && err < ret) { + drm_dbg_kms(aux->drm_dev, + "%s: Partial I2C reply: requested %zu bytes got %d bytes\n", + aux->name, msg.size, err); + ret = err; + } + + msg.size -= err; + msg.buffer += err; + } + + return ret; +} + +/* + * Bizlink designed DP->DVI-D Dual Link adapters require the I2C over AUX + * packets to be as large as possible. If not, the I2C transactions never + * succeed. Hence the default is maximum. + */ +static int dp_aux_i2c_transfer_size __read_mostly = DP_AUX_MAX_PAYLOAD_BYTES; +module_param_unsafe(dp_aux_i2c_transfer_size, int, 0644); +MODULE_PARM_DESC(dp_aux_i2c_transfer_size, + "Number of bytes to transfer in a single I2C over DP AUX CH message, (1-16, default 16)"); + +static int drm_dp_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, + int num) +{ + struct drm_dp_aux *aux = adapter->algo_data; + unsigned int i, j; + unsigned transfer_size; + struct drm_dp_aux_msg msg; + int err = 0; + + dp_aux_i2c_transfer_size = clamp(dp_aux_i2c_transfer_size, 1, DP_AUX_MAX_PAYLOAD_BYTES); + + memset(&msg, 0, sizeof(msg)); + + for (i = 0; i < num; i++) { + msg.address = msgs[i].addr; + drm_dp_i2c_msg_set_request(&msg, &msgs[i]); + /* Send a bare address packet to start the transaction. + * Zero sized messages specify an address only (bare + * address) transaction. + */ + msg.buffer = NULL; + msg.size = 0; + err = drm_dp_i2c_do_msg(aux, &msg); + + /* + * Reset msg.request in case in case it got + * changed into a WRITE_STATUS_UPDATE. + */ + drm_dp_i2c_msg_set_request(&msg, &msgs[i]); + + if (err < 0) + break; + /* We want each transaction to be as large as possible, but + * we'll go to smaller sizes if the hardware gives us a + * short reply. + */ + transfer_size = dp_aux_i2c_transfer_size; + for (j = 0; j < msgs[i].len; j += msg.size) { + msg.buffer = msgs[i].buf + j; + msg.size = min(transfer_size, msgs[i].len - j); + + err = drm_dp_i2c_drain_msg(aux, &msg); + + /* + * Reset msg.request in case in case it got + * changed into a WRITE_STATUS_UPDATE. + */ + drm_dp_i2c_msg_set_request(&msg, &msgs[i]); + + if (err < 0) + break; + transfer_size = err; + } + if (err < 0) + break; + } + if (err >= 0) + err = num; + /* Send a bare address packet to close out the transaction. + * Zero sized messages specify an address only (bare + * address) transaction. + */ + msg.request &= ~DP_AUX_I2C_MOT; + msg.buffer = NULL; + msg.size = 0; + (void)drm_dp_i2c_do_msg(aux, &msg); + + return err; +} + +static const struct i2c_algorithm drm_dp_i2c_algo = { + .functionality = drm_dp_i2c_functionality, + .master_xfer = drm_dp_i2c_xfer, +}; + +static struct drm_dp_aux *i2c_to_aux(struct i2c_adapter *i2c) +{ + return container_of(i2c, struct drm_dp_aux, ddc); +} + +static void lock_bus(struct i2c_adapter *i2c, unsigned int flags) +{ + mutex_lock(&i2c_to_aux(i2c)->hw_mutex); +} + +static int trylock_bus(struct i2c_adapter *i2c, unsigned int flags) +{ + return mutex_trylock(&i2c_to_aux(i2c)->hw_mutex); +} + +static void unlock_bus(struct i2c_adapter *i2c, unsigned int flags) +{ + mutex_unlock(&i2c_to_aux(i2c)->hw_mutex); +} + +static const struct i2c_lock_operations drm_dp_i2c_lock_ops = { + .lock_bus = lock_bus, + .trylock_bus = trylock_bus, + .unlock_bus = unlock_bus, +}; + +static int drm_dp_aux_get_crc(struct drm_dp_aux *aux, u8 *crc) +{ + u8 buf, count; + int ret; + + ret = drm_dp_dpcd_readb(aux, DP_TEST_SINK, &buf); + if (ret < 0) + return ret; + + WARN_ON(!(buf & DP_TEST_SINK_START)); + + ret = drm_dp_dpcd_readb(aux, DP_TEST_SINK_MISC, &buf); + if (ret < 0) + return ret; + + count = buf & DP_TEST_COUNT_MASK; + if (count == aux->crc_count) + return -EAGAIN; /* No CRC yet */ + + aux->crc_count = count; + + /* + * At DP_TEST_CRC_R_CR, there's 6 bytes containing CRC data, 2 bytes + * per component (RGB or CrYCb). + */ + ret = drm_dp_dpcd_read(aux, DP_TEST_CRC_R_CR, crc, 6); + if (ret < 0) + return ret; + + return 0; +} + +static void drm_dp_aux_crc_work(struct work_struct *work) +{ + struct drm_dp_aux *aux = container_of(work, struct drm_dp_aux, + crc_work); + struct drm_crtc *crtc; + u8 crc_bytes[6]; + uint32_t crcs[3]; + int ret; + + if (WARN_ON(!aux->crtc)) + return; + + crtc = aux->crtc; + while (crtc->crc.opened) { + drm_crtc_wait_one_vblank(crtc); + if (!crtc->crc.opened) + break; + + ret = drm_dp_aux_get_crc(aux, crc_bytes); + if (ret == -EAGAIN) { + usleep_range(1000, 2000); + ret = drm_dp_aux_get_crc(aux, crc_bytes); + } + + if (ret == -EAGAIN) { + drm_dbg_kms(aux->drm_dev, "%s: Get CRC failed after retrying: %d\n", + aux->name, ret); + continue; + } else if (ret) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to get a CRC: %d\n", aux->name, ret); + continue; + } + + crcs[0] = crc_bytes[0] | crc_bytes[1] << 8; + crcs[1] = crc_bytes[2] | crc_bytes[3] << 8; + crcs[2] = crc_bytes[4] | crc_bytes[5] << 8; + drm_crtc_add_crc_entry(crtc, false, 0, crcs); + } +} + +/** + * drm_dp_remote_aux_init() - minimally initialise a remote aux channel + * @aux: DisplayPort AUX channel + * + * Used for remote aux channel in general. Merely initialize the crc work + * struct. + */ +void drm_dp_remote_aux_init(struct drm_dp_aux *aux) +{ + INIT_WORK(&aux->crc_work, drm_dp_aux_crc_work); +} +EXPORT_SYMBOL(drm_dp_remote_aux_init); + +/** + * drm_dp_aux_init() - minimally initialise an aux channel + * @aux: DisplayPort AUX channel + * + * If you need to use the drm_dp_aux's i2c adapter prior to registering it with + * the outside world, call drm_dp_aux_init() first. For drivers which are + * grandparents to their AUX adapters (e.g. the AUX adapter is parented by a + * &drm_connector), you must still call drm_dp_aux_register() once the connector + * has been registered to allow userspace access to the auxiliary DP channel. + * Likewise, for such drivers you should also assign &drm_dp_aux.drm_dev as + * early as possible so that the &drm_device that corresponds to the AUX adapter + * may be mentioned in debugging output from the DRM DP helpers. + * + * For devices which use a separate platform device for their AUX adapters, this + * may be called as early as required by the driver. + * + */ +void drm_dp_aux_init(struct drm_dp_aux *aux) +{ + mutex_init(&aux->hw_mutex); + mutex_init(&aux->cec.lock); + INIT_WORK(&aux->crc_work, drm_dp_aux_crc_work); + + aux->ddc.algo = &drm_dp_i2c_algo; + aux->ddc.algo_data = aux; + aux->ddc.retries = 3; + + aux->ddc.lock_ops = &drm_dp_i2c_lock_ops; +} +EXPORT_SYMBOL(drm_dp_aux_init); + +/** + * drm_dp_aux_register() - initialise and register aux channel + * @aux: DisplayPort AUX channel + * + * Automatically calls drm_dp_aux_init() if this hasn't been done yet. This + * should only be called once the parent of @aux, &drm_dp_aux.dev, is + * initialized. For devices which are grandparents of their AUX channels, + * &drm_dp_aux.dev will typically be the &drm_connector &device which + * corresponds to @aux. For these devices, it's advised to call + * drm_dp_aux_register() in &drm_connector_funcs.late_register, and likewise to + * call drm_dp_aux_unregister() in &drm_connector_funcs.early_unregister. + * Functions which don't follow this will likely Oops when + * %CONFIG_DRM_DP_AUX_CHARDEV is enabled. + * + * For devices where the AUX channel is a device that exists independently of + * the &drm_device that uses it, such as SoCs and bridge devices, it is + * recommended to call drm_dp_aux_register() after a &drm_device has been + * assigned to &drm_dp_aux.drm_dev, and likewise to call + * drm_dp_aux_unregister() once the &drm_device should no longer be associated + * with the AUX channel (e.g. on bridge detach). + * + * Drivers which need to use the aux channel before either of the two points + * mentioned above need to call drm_dp_aux_init() in order to use the AUX + * channel before registration. + * + * Returns 0 on success or a negative error code on failure. + */ +int drm_dp_aux_register(struct drm_dp_aux *aux) +{ + int ret; + + WARN_ON_ONCE(!aux->drm_dev); + + if (!aux->ddc.algo) + drm_dp_aux_init(aux); + + aux->ddc.class = I2C_CLASS_DDC; + aux->ddc.owner = THIS_MODULE; + aux->ddc.dev.parent = aux->dev; + + strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev), + sizeof(aux->ddc.name)); + + ret = drm_dp_aux_register_devnode(aux); + if (ret) + return ret; + + ret = i2c_add_adapter(&aux->ddc); + if (ret) { + drm_dp_aux_unregister_devnode(aux); + return ret; + } + + return 0; +} +EXPORT_SYMBOL(drm_dp_aux_register); + +/** + * drm_dp_aux_unregister() - unregister an AUX adapter + * @aux: DisplayPort AUX channel + */ +void drm_dp_aux_unregister(struct drm_dp_aux *aux) +{ + drm_dp_aux_unregister_devnode(aux); + i2c_del_adapter(&aux->ddc); +} +EXPORT_SYMBOL(drm_dp_aux_unregister); + +#define PSR_SETUP_TIME(x) [DP_PSR_SETUP_TIME_ ## x >> DP_PSR_SETUP_TIME_SHIFT] = (x) + +/** + * drm_dp_psr_setup_time() - PSR setup in time usec + * @psr_cap: PSR capabilities from DPCD + * + * Returns: + * PSR setup time for the panel in microseconds, negative + * error code on failure. + */ +int drm_dp_psr_setup_time(const u8 psr_cap[EDP_PSR_RECEIVER_CAP_SIZE]) +{ + static const u16 psr_setup_time_us[] = { + PSR_SETUP_TIME(330), + PSR_SETUP_TIME(275), + PSR_SETUP_TIME(220), + PSR_SETUP_TIME(165), + PSR_SETUP_TIME(110), + PSR_SETUP_TIME(55), + PSR_SETUP_TIME(0), + }; + int i; + + i = (psr_cap[1] & DP_PSR_SETUP_TIME_MASK) >> DP_PSR_SETUP_TIME_SHIFT; + if (i >= ARRAY_SIZE(psr_setup_time_us)) + return -EINVAL; + + return psr_setup_time_us[i]; +} +EXPORT_SYMBOL(drm_dp_psr_setup_time); + +#undef PSR_SETUP_TIME + +/** + * drm_dp_start_crc() - start capture of frame CRCs + * @aux: DisplayPort AUX channel + * @crtc: CRTC displaying the frames whose CRCs are to be captured + * + * Returns 0 on success or a negative error code on failure. + */ +int drm_dp_start_crc(struct drm_dp_aux *aux, struct drm_crtc *crtc) +{ + u8 buf; + int ret; + + ret = drm_dp_dpcd_readb(aux, DP_TEST_SINK, &buf); + if (ret < 0) + return ret; + + ret = drm_dp_dpcd_writeb(aux, DP_TEST_SINK, buf | DP_TEST_SINK_START); + if (ret < 0) + return ret; + + aux->crc_count = 0; + aux->crtc = crtc; + schedule_work(&aux->crc_work); + + return 0; +} +EXPORT_SYMBOL(drm_dp_start_crc); + +/** + * drm_dp_stop_crc() - stop capture of frame CRCs + * @aux: DisplayPort AUX channel + * + * Returns 0 on success or a negative error code on failure. + */ +int drm_dp_stop_crc(struct drm_dp_aux *aux) +{ + u8 buf; + int ret; + + ret = drm_dp_dpcd_readb(aux, DP_TEST_SINK, &buf); + if (ret < 0) + return ret; + + ret = drm_dp_dpcd_writeb(aux, DP_TEST_SINK, buf & ~DP_TEST_SINK_START); + if (ret < 0) + return ret; + + flush_work(&aux->crc_work); + aux->crtc = NULL; + + return 0; +} +EXPORT_SYMBOL(drm_dp_stop_crc); + +struct dpcd_quirk { + u8 oui[3]; + u8 device_id[6]; + bool is_branch; + u32 quirks; +}; + +#define OUI(first, second, third) { (first), (second), (third) } +#define DEVICE_ID(first, second, third, fourth, fifth, sixth) \ + { (first), (second), (third), (fourth), (fifth), (sixth) } + +#define DEVICE_ID_ANY DEVICE_ID(0, 0, 0, 0, 0, 0) + +static const struct dpcd_quirk dpcd_quirk_list[] = { + /* Analogix 7737 needs reduced M and N at HBR2 link rates */ + { OUI(0x00, 0x22, 0xb9), DEVICE_ID_ANY, true, BIT(DP_DPCD_QUIRK_CONSTANT_N) }, + /* LG LP140WF6-SPM1 eDP panel */ + { OUI(0x00, 0x22, 0xb9), DEVICE_ID('s', 'i', 'v', 'a', 'r', 'T'), false, BIT(DP_DPCD_QUIRK_CONSTANT_N) }, + /* Apple panels need some additional handling to support PSR */ + { OUI(0x00, 0x10, 0xfa), DEVICE_ID_ANY, false, BIT(DP_DPCD_QUIRK_NO_PSR) }, + /* CH7511 seems to leave SINK_COUNT zeroed */ + { OUI(0x00, 0x00, 0x00), DEVICE_ID('C', 'H', '7', '5', '1', '1'), false, BIT(DP_DPCD_QUIRK_NO_SINK_COUNT) }, + /* Synaptics DP1.4 MST hubs can support DSC without virtual DPCD */ + { OUI(0x90, 0xCC, 0x24), DEVICE_ID_ANY, true, BIT(DP_DPCD_QUIRK_DSC_WITHOUT_VIRTUAL_DPCD) }, + /* Apple MacBookPro 2017 15 inch eDP Retina panel reports too low DP_MAX_LINK_RATE */ + { OUI(0x00, 0x10, 0xfa), DEVICE_ID(101, 68, 21, 101, 98, 97), false, BIT(DP_DPCD_QUIRK_CAN_DO_MAX_LINK_RATE_3_24_GBPS) }, +}; + +#undef OUI + +/* + * Get a bit mask of DPCD quirks for the sink/branch device identified by + * ident. The quirk data is shared but it's up to the drivers to act on the + * data. + * + * For now, only the OUI (first three bytes) is used, but this may be extended + * to device identification string and hardware/firmware revisions later. + */ +static u32 +drm_dp_get_quirks(const struct drm_dp_dpcd_ident *ident, bool is_branch) +{ + const struct dpcd_quirk *quirk; + u32 quirks = 0; + int i; + u8 any_device[] = DEVICE_ID_ANY; + + for (i = 0; i < ARRAY_SIZE(dpcd_quirk_list); i++) { + quirk = &dpcd_quirk_list[i]; + + if (quirk->is_branch != is_branch) + continue; + + if (memcmp(quirk->oui, ident->oui, sizeof(ident->oui)) != 0) + continue; + + if (memcmp(quirk->device_id, any_device, sizeof(any_device)) != 0 && + memcmp(quirk->device_id, ident->device_id, sizeof(ident->device_id)) != 0) + continue; + + quirks |= quirk->quirks; + } + + return quirks; +} + +#undef DEVICE_ID_ANY +#undef DEVICE_ID + +/** + * drm_dp_read_desc - read sink/branch descriptor from DPCD + * @aux: DisplayPort AUX channel + * @desc: Device descriptor to fill from DPCD + * @is_branch: true for branch devices, false for sink devices + * + * Read DPCD 0x400 (sink) or 0x500 (branch) into @desc. Also debug log the + * identification. + * + * Returns 0 on success or a negative error code on failure. + */ +int drm_dp_read_desc(struct drm_dp_aux *aux, struct drm_dp_desc *desc, + bool is_branch) +{ + struct drm_dp_dpcd_ident *ident = &desc->ident; + unsigned int offset = is_branch ? DP_BRANCH_OUI : DP_SINK_OUI; + int ret, dev_id_len; + + ret = drm_dp_dpcd_read(aux, offset, ident, sizeof(*ident)); + if (ret < 0) + return ret; + + desc->quirks = drm_dp_get_quirks(ident, is_branch); + + dev_id_len = strnlen(ident->device_id, sizeof(ident->device_id)); + + drm_dbg_kms(aux->drm_dev, + "%s: DP %s: OUI %*phD dev-ID %*pE HW-rev %d.%d SW-rev %d.%d quirks 0x%04x\n", + aux->name, is_branch ? "branch" : "sink", + (int)sizeof(ident->oui), ident->oui, dev_id_len, + ident->device_id, ident->hw_rev >> 4, ident->hw_rev & 0xf, + ident->sw_major_rev, ident->sw_minor_rev, desc->quirks); + + return 0; +} +EXPORT_SYMBOL(drm_dp_read_desc); + +/** + * drm_dp_dsc_sink_max_slice_count() - Get the max slice count + * supported by the DSC sink. + * @dsc_dpcd: DSC capabilities from DPCD + * @is_edp: true if its eDP, false for DP + * + * Read the slice capabilities DPCD register from DSC sink to get + * the maximum slice count supported. This is used to populate + * the DSC parameters in the &struct drm_dsc_config by the driver. + * Driver creates an infoframe using these parameters to populate + * &struct drm_dsc_pps_infoframe. These are sent to the sink using DSC + * infoframe using the helper function drm_dsc_pps_infoframe_pack() + * + * Returns: + * Maximum slice count supported by DSC sink or 0 its invalid + */ +u8 drm_dp_dsc_sink_max_slice_count(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE], + bool is_edp) +{ + u8 slice_cap1 = dsc_dpcd[DP_DSC_SLICE_CAP_1 - DP_DSC_SUPPORT]; + + if (is_edp) { + /* For eDP, register DSC_SLICE_CAPABILITIES_1 gives slice count */ + if (slice_cap1 & DP_DSC_4_PER_DP_DSC_SINK) + return 4; + if (slice_cap1 & DP_DSC_2_PER_DP_DSC_SINK) + return 2; + if (slice_cap1 & DP_DSC_1_PER_DP_DSC_SINK) + return 1; + } else { + /* For DP, use values from DSC_SLICE_CAP_1 and DSC_SLICE_CAP2 */ + u8 slice_cap2 = dsc_dpcd[DP_DSC_SLICE_CAP_2 - DP_DSC_SUPPORT]; + + if (slice_cap2 & DP_DSC_24_PER_DP_DSC_SINK) + return 24; + if (slice_cap2 & DP_DSC_20_PER_DP_DSC_SINK) + return 20; + if (slice_cap2 & DP_DSC_16_PER_DP_DSC_SINK) + return 16; + if (slice_cap1 & DP_DSC_12_PER_DP_DSC_SINK) + return 12; + if (slice_cap1 & DP_DSC_10_PER_DP_DSC_SINK) + return 10; + if (slice_cap1 & DP_DSC_8_PER_DP_DSC_SINK) + return 8; + if (slice_cap1 & DP_DSC_6_PER_DP_DSC_SINK) + return 6; + if (slice_cap1 & DP_DSC_4_PER_DP_DSC_SINK) + return 4; + if (slice_cap1 & DP_DSC_2_PER_DP_DSC_SINK) + return 2; + if (slice_cap1 & DP_DSC_1_PER_DP_DSC_SINK) + return 1; + } + + return 0; +} +EXPORT_SYMBOL(drm_dp_dsc_sink_max_slice_count); + +/** + * drm_dp_dsc_sink_line_buf_depth() - Get the line buffer depth in bits + * @dsc_dpcd: DSC capabilities from DPCD + * + * Read the DSC DPCD register to parse the line buffer depth in bits which is + * number of bits of precision within the decoder line buffer supported by + * the DSC sink. This is used to populate the DSC parameters in the + * &struct drm_dsc_config by the driver. + * Driver creates an infoframe using these parameters to populate + * &struct drm_dsc_pps_infoframe. These are sent to the sink using DSC + * infoframe using the helper function drm_dsc_pps_infoframe_pack() + * + * Returns: + * Line buffer depth supported by DSC panel or 0 its invalid + */ +u8 drm_dp_dsc_sink_line_buf_depth(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE]) +{ + u8 line_buf_depth = dsc_dpcd[DP_DSC_LINE_BUF_BIT_DEPTH - DP_DSC_SUPPORT]; + + switch (line_buf_depth & DP_DSC_LINE_BUF_BIT_DEPTH_MASK) { + case DP_DSC_LINE_BUF_BIT_DEPTH_9: + return 9; + case DP_DSC_LINE_BUF_BIT_DEPTH_10: + return 10; + case DP_DSC_LINE_BUF_BIT_DEPTH_11: + return 11; + case DP_DSC_LINE_BUF_BIT_DEPTH_12: + return 12; + case DP_DSC_LINE_BUF_BIT_DEPTH_13: + return 13; + case DP_DSC_LINE_BUF_BIT_DEPTH_14: + return 14; + case DP_DSC_LINE_BUF_BIT_DEPTH_15: + return 15; + case DP_DSC_LINE_BUF_BIT_DEPTH_16: + return 16; + case DP_DSC_LINE_BUF_BIT_DEPTH_8: + return 8; + } + + return 0; +} +EXPORT_SYMBOL(drm_dp_dsc_sink_line_buf_depth); + +/** + * drm_dp_dsc_sink_supported_input_bpcs() - Get all the input bits per component + * values supported by the DSC sink. + * @dsc_dpcd: DSC capabilities from DPCD + * @dsc_bpc: An array to be filled by this helper with supported + * input bpcs. + * + * Read the DSC DPCD from the sink device to parse the supported bits per + * component values. This is used to populate the DSC parameters + * in the &struct drm_dsc_config by the driver. + * Driver creates an infoframe using these parameters to populate + * &struct drm_dsc_pps_infoframe. These are sent to the sink using DSC + * infoframe using the helper function drm_dsc_pps_infoframe_pack() + * + * Returns: + * Number of input BPC values parsed from the DPCD + */ +int drm_dp_dsc_sink_supported_input_bpcs(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE], + u8 dsc_bpc[3]) +{ + int num_bpc = 0; + u8 color_depth = dsc_dpcd[DP_DSC_DEC_COLOR_DEPTH_CAP - DP_DSC_SUPPORT]; + + if (color_depth & DP_DSC_12_BPC) + dsc_bpc[num_bpc++] = 12; + if (color_depth & DP_DSC_10_BPC) + dsc_bpc[num_bpc++] = 10; + if (color_depth & DP_DSC_8_BPC) + dsc_bpc[num_bpc++] = 8; + + return num_bpc; +} +EXPORT_SYMBOL(drm_dp_dsc_sink_supported_input_bpcs); + +static int drm_dp_read_lttpr_regs(struct drm_dp_aux *aux, + const u8 dpcd[DP_RECEIVER_CAP_SIZE], int address, + u8 *buf, int buf_size) +{ + /* + * At least the DELL P2715Q monitor with a DPCD_REV < 0x14 returns + * corrupted values when reading from the 0xF0000- range with a block + * size bigger than 1. + */ + int block_size = dpcd[DP_DPCD_REV] < 0x14 ? 1 : buf_size; + int offset; + int ret; + + for (offset = 0; offset < buf_size; offset += block_size) { + ret = drm_dp_dpcd_read(aux, + address + offset, + &buf[offset], block_size); + if (ret < 0) + return ret; + + WARN_ON(ret != block_size); + } + + return 0; +} + +/** + * drm_dp_read_lttpr_common_caps - read the LTTPR common capabilities + * @aux: DisplayPort AUX channel + * @dpcd: DisplayPort configuration data + * @caps: buffer to return the capability info in + * + * Read capabilities common to all LTTPRs. + * + * Returns 0 on success or a negative error code on failure. + */ +int drm_dp_read_lttpr_common_caps(struct drm_dp_aux *aux, + const u8 dpcd[DP_RECEIVER_CAP_SIZE], + u8 caps[DP_LTTPR_COMMON_CAP_SIZE]) +{ + return drm_dp_read_lttpr_regs(aux, dpcd, + DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV, + caps, DP_LTTPR_COMMON_CAP_SIZE); +} +EXPORT_SYMBOL(drm_dp_read_lttpr_common_caps); + +/** + * drm_dp_read_lttpr_phy_caps - read the capabilities for a given LTTPR PHY + * @aux: DisplayPort AUX channel + * @dpcd: DisplayPort configuration data + * @dp_phy: LTTPR PHY to read the capabilities for + * @caps: buffer to return the capability info in + * + * Read the capabilities for the given LTTPR PHY. + * + * Returns 0 on success or a negative error code on failure. + */ +int drm_dp_read_lttpr_phy_caps(struct drm_dp_aux *aux, + const u8 dpcd[DP_RECEIVER_CAP_SIZE], + enum drm_dp_phy dp_phy, + u8 caps[DP_LTTPR_PHY_CAP_SIZE]) +{ + return drm_dp_read_lttpr_regs(aux, dpcd, + DP_TRAINING_AUX_RD_INTERVAL_PHY_REPEATER(dp_phy), + caps, DP_LTTPR_PHY_CAP_SIZE); +} +EXPORT_SYMBOL(drm_dp_read_lttpr_phy_caps); + +static u8 dp_lttpr_common_cap(const u8 caps[DP_LTTPR_COMMON_CAP_SIZE], int r) +{ + return caps[r - DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV]; +} + +/** + * drm_dp_lttpr_count - get the number of detected LTTPRs + * @caps: LTTPR common capabilities + * + * Get the number of detected LTTPRs from the LTTPR common capabilities info. + * + * Returns: + * -ERANGE if more than supported number (8) of LTTPRs are detected + * -EINVAL if the DP_PHY_REPEATER_CNT register contains an invalid value + * otherwise the number of detected LTTPRs + */ +int drm_dp_lttpr_count(const u8 caps[DP_LTTPR_COMMON_CAP_SIZE]) +{ + u8 count = dp_lttpr_common_cap(caps, DP_PHY_REPEATER_CNT); + + switch (hweight8(count)) { + case 0: + return 0; + case 1: + return 8 - ilog2(count); + case 8: + return -ERANGE; + default: + return -EINVAL; + } +} +EXPORT_SYMBOL(drm_dp_lttpr_count); + +/** + * drm_dp_lttpr_max_link_rate - get the maximum link rate supported by all LTTPRs + * @caps: LTTPR common capabilities + * + * Returns the maximum link rate supported by all detected LTTPRs. + */ +int drm_dp_lttpr_max_link_rate(const u8 caps[DP_LTTPR_COMMON_CAP_SIZE]) +{ + u8 rate = dp_lttpr_common_cap(caps, DP_MAX_LINK_RATE_PHY_REPEATER); + + return drm_dp_bw_code_to_link_rate(rate); +} +EXPORT_SYMBOL(drm_dp_lttpr_max_link_rate); + +/** + * drm_dp_lttpr_max_lane_count - get the maximum lane count supported by all LTTPRs + * @caps: LTTPR common capabilities + * + * Returns the maximum lane count supported by all detected LTTPRs. + */ +int drm_dp_lttpr_max_lane_count(const u8 caps[DP_LTTPR_COMMON_CAP_SIZE]) +{ + u8 max_lanes = dp_lttpr_common_cap(caps, DP_MAX_LANE_COUNT_PHY_REPEATER); + + return max_lanes & DP_MAX_LANE_COUNT_MASK; +} +EXPORT_SYMBOL(drm_dp_lttpr_max_lane_count); + +/** + * drm_dp_lttpr_voltage_swing_level_3_supported - check for LTTPR vswing3 support + * @caps: LTTPR PHY capabilities + * + * Returns true if the @caps for an LTTPR TX PHY indicate support for + * voltage swing level 3. + */ +bool +drm_dp_lttpr_voltage_swing_level_3_supported(const u8 caps[DP_LTTPR_PHY_CAP_SIZE]) +{ + u8 txcap = dp_lttpr_phy_cap(caps, DP_TRANSMITTER_CAPABILITY_PHY_REPEATER1); + + return txcap & DP_VOLTAGE_SWING_LEVEL_3_SUPPORTED; +} +EXPORT_SYMBOL(drm_dp_lttpr_voltage_swing_level_3_supported); + +/** + * drm_dp_lttpr_pre_emphasis_level_3_supported - check for LTTPR preemph3 support + * @caps: LTTPR PHY capabilities + * + * Returns true if the @caps for an LTTPR TX PHY indicate support for + * pre-emphasis level 3. + */ +bool +drm_dp_lttpr_pre_emphasis_level_3_supported(const u8 caps[DP_LTTPR_PHY_CAP_SIZE]) +{ + u8 txcap = dp_lttpr_phy_cap(caps, DP_TRANSMITTER_CAPABILITY_PHY_REPEATER1); + + return txcap & DP_PRE_EMPHASIS_LEVEL_3_SUPPORTED; +} +EXPORT_SYMBOL(drm_dp_lttpr_pre_emphasis_level_3_supported); + +/** + * drm_dp_get_phy_test_pattern() - get the requested pattern from the sink. + * @aux: DisplayPort AUX channel + * @data: DP phy compliance test parameters. + * + * Returns 0 on success or a negative error code on failure. + */ +int drm_dp_get_phy_test_pattern(struct drm_dp_aux *aux, + struct drm_dp_phy_test_params *data) +{ + int err; + u8 rate, lanes; + + err = drm_dp_dpcd_readb(aux, DP_TEST_LINK_RATE, &rate); + if (err < 0) + return err; + data->link_rate = drm_dp_bw_code_to_link_rate(rate); + + err = drm_dp_dpcd_readb(aux, DP_TEST_LANE_COUNT, &lanes); + if (err < 0) + return err; + data->num_lanes = lanes & DP_MAX_LANE_COUNT_MASK; + + if (lanes & DP_ENHANCED_FRAME_CAP) + data->enhanced_frame_cap = true; + + err = drm_dp_dpcd_readb(aux, DP_PHY_TEST_PATTERN, &data->phy_pattern); + if (err < 0) + return err; + + switch (data->phy_pattern) { + case DP_PHY_TEST_PATTERN_80BIT_CUSTOM: + err = drm_dp_dpcd_read(aux, DP_TEST_80BIT_CUSTOM_PATTERN_7_0, + &data->custom80, sizeof(data->custom80)); + if (err < 0) + return err; + + break; + case DP_PHY_TEST_PATTERN_CP2520: + err = drm_dp_dpcd_read(aux, DP_TEST_HBR2_SCRAMBLER_RESET, + &data->hbr2_reset, + sizeof(data->hbr2_reset)); + if (err < 0) + return err; + } + + return 0; +} +EXPORT_SYMBOL(drm_dp_get_phy_test_pattern); + +/** + * drm_dp_set_phy_test_pattern() - set the pattern to the sink. + * @aux: DisplayPort AUX channel + * @data: DP phy compliance test parameters. + * @dp_rev: DP revision to use for compliance testing + * + * Returns 0 on success or a negative error code on failure. + */ +int drm_dp_set_phy_test_pattern(struct drm_dp_aux *aux, + struct drm_dp_phy_test_params *data, u8 dp_rev) +{ + int err, i; + u8 test_pattern; + + test_pattern = data->phy_pattern; + if (dp_rev < 0x12) { + test_pattern = (test_pattern << 2) & + DP_LINK_QUAL_PATTERN_11_MASK; + err = drm_dp_dpcd_writeb(aux, DP_TRAINING_PATTERN_SET, + test_pattern); + if (err < 0) + return err; + } else { + for (i = 0; i < data->num_lanes; i++) { + err = drm_dp_dpcd_writeb(aux, + DP_LINK_QUAL_LANE0_SET + i, + test_pattern); + if (err < 0) + return err; + } + } + + return 0; +} +EXPORT_SYMBOL(drm_dp_set_phy_test_pattern); + +static const char *dp_pixelformat_get_name(enum dp_pixelformat pixelformat) +{ + if (pixelformat < 0 || pixelformat > DP_PIXELFORMAT_RESERVED) + return "Invalid"; + + switch (pixelformat) { + case DP_PIXELFORMAT_RGB: + return "RGB"; + case DP_PIXELFORMAT_YUV444: + return "YUV444"; + case DP_PIXELFORMAT_YUV422: + return "YUV422"; + case DP_PIXELFORMAT_YUV420: + return "YUV420"; + case DP_PIXELFORMAT_Y_ONLY: + return "Y_ONLY"; + case DP_PIXELFORMAT_RAW: + return "RAW"; + default: + return "Reserved"; + } +} + +static const char *dp_colorimetry_get_name(enum dp_pixelformat pixelformat, + enum dp_colorimetry colorimetry) +{ + if (pixelformat < 0 || pixelformat > DP_PIXELFORMAT_RESERVED) + return "Invalid"; + + switch (colorimetry) { + case DP_COLORIMETRY_DEFAULT: + switch (pixelformat) { + case DP_PIXELFORMAT_RGB: + return "sRGB"; + case DP_PIXELFORMAT_YUV444: + case DP_PIXELFORMAT_YUV422: + case DP_PIXELFORMAT_YUV420: + return "BT.601"; + case DP_PIXELFORMAT_Y_ONLY: + return "DICOM PS3.14"; + case DP_PIXELFORMAT_RAW: + return "Custom Color Profile"; + default: + return "Reserved"; + } + case DP_COLORIMETRY_RGB_WIDE_FIXED: /* and DP_COLORIMETRY_BT709_YCC */ + switch (pixelformat) { + case DP_PIXELFORMAT_RGB: + return "Wide Fixed"; + case DP_PIXELFORMAT_YUV444: + case DP_PIXELFORMAT_YUV422: + case DP_PIXELFORMAT_YUV420: + return "BT.709"; + default: + return "Reserved"; + } + case DP_COLORIMETRY_RGB_WIDE_FLOAT: /* and DP_COLORIMETRY_XVYCC_601 */ + switch (pixelformat) { + case DP_PIXELFORMAT_RGB: + return "Wide Float"; + case DP_PIXELFORMAT_YUV444: + case DP_PIXELFORMAT_YUV422: + case DP_PIXELFORMAT_YUV420: + return "xvYCC 601"; + default: + return "Reserved"; + } + case DP_COLORIMETRY_OPRGB: /* and DP_COLORIMETRY_XVYCC_709 */ + switch (pixelformat) { + case DP_PIXELFORMAT_RGB: + return "OpRGB"; + case DP_PIXELFORMAT_YUV444: + case DP_PIXELFORMAT_YUV422: + case DP_PIXELFORMAT_YUV420: + return "xvYCC 709"; + default: + return "Reserved"; + } + case DP_COLORIMETRY_DCI_P3_RGB: /* and DP_COLORIMETRY_SYCC_601 */ + switch (pixelformat) { + case DP_PIXELFORMAT_RGB: + return "DCI-P3"; + case DP_PIXELFORMAT_YUV444: + case DP_PIXELFORMAT_YUV422: + case DP_PIXELFORMAT_YUV420: + return "sYCC 601"; + default: + return "Reserved"; + } + case DP_COLORIMETRY_RGB_CUSTOM: /* and DP_COLORIMETRY_OPYCC_601 */ + switch (pixelformat) { + case DP_PIXELFORMAT_RGB: + return "Custom Profile"; + case DP_PIXELFORMAT_YUV444: + case DP_PIXELFORMAT_YUV422: + case DP_PIXELFORMAT_YUV420: + return "OpYCC 601"; + default: + return "Reserved"; + } + case DP_COLORIMETRY_BT2020_RGB: /* and DP_COLORIMETRY_BT2020_CYCC */ + switch (pixelformat) { + case DP_PIXELFORMAT_RGB: + return "BT.2020 RGB"; + case DP_PIXELFORMAT_YUV444: + case DP_PIXELFORMAT_YUV422: + case DP_PIXELFORMAT_YUV420: + return "BT.2020 CYCC"; + default: + return "Reserved"; + } + case DP_COLORIMETRY_BT2020_YCC: + switch (pixelformat) { + case DP_PIXELFORMAT_YUV444: + case DP_PIXELFORMAT_YUV422: + case DP_PIXELFORMAT_YUV420: + return "BT.2020 YCC"; + default: + return "Reserved"; + } + default: + return "Invalid"; + } +} + +static const char *dp_dynamic_range_get_name(enum dp_dynamic_range dynamic_range) +{ + switch (dynamic_range) { + case DP_DYNAMIC_RANGE_VESA: + return "VESA range"; + case DP_DYNAMIC_RANGE_CTA: + return "CTA range"; + default: + return "Invalid"; + } +} + +static const char *dp_content_type_get_name(enum dp_content_type content_type) +{ + switch (content_type) { + case DP_CONTENT_TYPE_NOT_DEFINED: + return "Not defined"; + case DP_CONTENT_TYPE_GRAPHICS: + return "Graphics"; + case DP_CONTENT_TYPE_PHOTO: + return "Photo"; + case DP_CONTENT_TYPE_VIDEO: + return "Video"; + case DP_CONTENT_TYPE_GAME: + return "Game"; + default: + return "Reserved"; + } +} + +void drm_dp_vsc_sdp_log(const char *level, struct device *dev, + const struct drm_dp_vsc_sdp *vsc) +{ +#define DP_SDP_LOG(fmt, ...) dev_printk(level, dev, fmt, ##__VA_ARGS__) + DP_SDP_LOG("DP SDP: %s, revision %u, length %u\n", "VSC", + vsc->revision, vsc->length); + DP_SDP_LOG(" pixelformat: %s\n", + dp_pixelformat_get_name(vsc->pixelformat)); + DP_SDP_LOG(" colorimetry: %s\n", + dp_colorimetry_get_name(vsc->pixelformat, vsc->colorimetry)); + DP_SDP_LOG(" bpc: %u\n", vsc->bpc); + DP_SDP_LOG(" dynamic range: %s\n", + dp_dynamic_range_get_name(vsc->dynamic_range)); + DP_SDP_LOG(" content type: %s\n", + dp_content_type_get_name(vsc->content_type)); +#undef DP_SDP_LOG +} +EXPORT_SYMBOL(drm_dp_vsc_sdp_log); + +/** + * drm_dp_get_pcon_max_frl_bw() - maximum frl supported by PCON + * @dpcd: DisplayPort configuration data + * @port_cap: port capabilities + * + * Returns maximum frl bandwidth supported by PCON in GBPS, + * returns 0 if not supported. + */ +int drm_dp_get_pcon_max_frl_bw(const u8 dpcd[DP_RECEIVER_CAP_SIZE], + const u8 port_cap[4]) +{ + int bw; + u8 buf; + + buf = port_cap[2]; + bw = buf & DP_PCON_MAX_FRL_BW; + + switch (bw) { + case DP_PCON_MAX_9GBPS: + return 9; + case DP_PCON_MAX_18GBPS: + return 18; + case DP_PCON_MAX_24GBPS: + return 24; + case DP_PCON_MAX_32GBPS: + return 32; + case DP_PCON_MAX_40GBPS: + return 40; + case DP_PCON_MAX_48GBPS: + return 48; + case DP_PCON_MAX_0GBPS: + default: + return 0; + } + + return 0; +} +EXPORT_SYMBOL(drm_dp_get_pcon_max_frl_bw); + +/** + * drm_dp_pcon_frl_prepare() - Prepare PCON for FRL. + * @aux: DisplayPort AUX channel + * @enable_frl_ready_hpd: Configure DP_PCON_ENABLE_HPD_READY. + * + * Returns 0 if success, else returns negative error code. + */ +int drm_dp_pcon_frl_prepare(struct drm_dp_aux *aux, bool enable_frl_ready_hpd) +{ + int ret; + u8 buf = DP_PCON_ENABLE_SOURCE_CTL_MODE | + DP_PCON_ENABLE_LINK_FRL_MODE; + + if (enable_frl_ready_hpd) + buf |= DP_PCON_ENABLE_HPD_READY; + + ret = drm_dp_dpcd_writeb(aux, DP_PCON_HDMI_LINK_CONFIG_1, buf); + + return ret; +} +EXPORT_SYMBOL(drm_dp_pcon_frl_prepare); + +/** + * drm_dp_pcon_is_frl_ready() - Is PCON ready for FRL + * @aux: DisplayPort AUX channel + * + * Returns true if success, else returns false. + */ +bool drm_dp_pcon_is_frl_ready(struct drm_dp_aux *aux) +{ + int ret; + u8 buf; + + ret = drm_dp_dpcd_readb(aux, DP_PCON_HDMI_TX_LINK_STATUS, &buf); + if (ret < 0) + return false; + + if (buf & DP_PCON_FRL_READY) + return true; + + return false; +} +EXPORT_SYMBOL(drm_dp_pcon_is_frl_ready); + +/** + * drm_dp_pcon_frl_configure_1() - Set HDMI LINK Configuration-Step1 + * @aux: DisplayPort AUX channel + * @max_frl_gbps: maximum frl bw to be configured between PCON and HDMI sink + * @frl_mode: FRL Training mode, it can be either Concurrent or Sequential. + * In Concurrent Mode, the FRL link bring up can be done along with + * DP Link training. In Sequential mode, the FRL link bring up is done prior to + * the DP Link training. + * + * Returns 0 if success, else returns negative error code. + */ + +int drm_dp_pcon_frl_configure_1(struct drm_dp_aux *aux, int max_frl_gbps, + u8 frl_mode) +{ + int ret; + u8 buf; + + ret = drm_dp_dpcd_readb(aux, DP_PCON_HDMI_LINK_CONFIG_1, &buf); + if (ret < 0) + return ret; + + if (frl_mode == DP_PCON_ENABLE_CONCURRENT_LINK) + buf |= DP_PCON_ENABLE_CONCURRENT_LINK; + else + buf &= ~DP_PCON_ENABLE_CONCURRENT_LINK; + + switch (max_frl_gbps) { + case 9: + buf |= DP_PCON_ENABLE_MAX_BW_9GBPS; + break; + case 18: + buf |= DP_PCON_ENABLE_MAX_BW_18GBPS; + break; + case 24: + buf |= DP_PCON_ENABLE_MAX_BW_24GBPS; + break; + case 32: + buf |= DP_PCON_ENABLE_MAX_BW_32GBPS; + break; + case 40: + buf |= DP_PCON_ENABLE_MAX_BW_40GBPS; + break; + case 48: + buf |= DP_PCON_ENABLE_MAX_BW_48GBPS; + break; + case 0: + buf |= DP_PCON_ENABLE_MAX_BW_0GBPS; + break; + default: + return -EINVAL; + } + + ret = drm_dp_dpcd_writeb(aux, DP_PCON_HDMI_LINK_CONFIG_1, buf); + if (ret < 0) + return ret; + + return 0; +} +EXPORT_SYMBOL(drm_dp_pcon_frl_configure_1); + +/** + * drm_dp_pcon_frl_configure_2() - Set HDMI Link configuration Step-2 + * @aux: DisplayPort AUX channel + * @max_frl_mask : Max FRL BW to be tried by the PCON with HDMI Sink + * @frl_type : FRL training type, can be Extended, or Normal. + * In Normal FRL training, the PCON tries each frl bw from the max_frl_mask + * starting from min, and stops when link training is successful. In Extended + * FRL training, all frl bw selected in the mask are trained by the PCON. + * + * Returns 0 if success, else returns negative error code. + */ +int drm_dp_pcon_frl_configure_2(struct drm_dp_aux *aux, int max_frl_mask, + u8 frl_type) +{ + int ret; + u8 buf = max_frl_mask; + + if (frl_type == DP_PCON_FRL_LINK_TRAIN_EXTENDED) + buf |= DP_PCON_FRL_LINK_TRAIN_EXTENDED; + else + buf &= ~DP_PCON_FRL_LINK_TRAIN_EXTENDED; + + ret = drm_dp_dpcd_writeb(aux, DP_PCON_HDMI_LINK_CONFIG_2, buf); + if (ret < 0) + return ret; + + return 0; +} +EXPORT_SYMBOL(drm_dp_pcon_frl_configure_2); + +/** + * drm_dp_pcon_reset_frl_config() - Re-Set HDMI Link configuration. + * @aux: DisplayPort AUX channel + * + * Returns 0 if success, else returns negative error code. + */ +int drm_dp_pcon_reset_frl_config(struct drm_dp_aux *aux) +{ + int ret; + + ret = drm_dp_dpcd_writeb(aux, DP_PCON_HDMI_LINK_CONFIG_1, 0x0); + if (ret < 0) + return ret; + + return 0; +} +EXPORT_SYMBOL(drm_dp_pcon_reset_frl_config); + +/** + * drm_dp_pcon_frl_enable() - Enable HDMI link through FRL + * @aux: DisplayPort AUX channel + * + * Returns 0 if success, else returns negative error code. + */ +int drm_dp_pcon_frl_enable(struct drm_dp_aux *aux) +{ + int ret; + u8 buf = 0; + + ret = drm_dp_dpcd_readb(aux, DP_PCON_HDMI_LINK_CONFIG_1, &buf); + if (ret < 0) + return ret; + if (!(buf & DP_PCON_ENABLE_SOURCE_CTL_MODE)) { + drm_dbg_kms(aux->drm_dev, "%s: PCON in Autonomous mode, can't enable FRL\n", + aux->name); + return -EINVAL; + } + buf |= DP_PCON_ENABLE_HDMI_LINK; + ret = drm_dp_dpcd_writeb(aux, DP_PCON_HDMI_LINK_CONFIG_1, buf); + if (ret < 0) + return ret; + + return 0; +} +EXPORT_SYMBOL(drm_dp_pcon_frl_enable); + +/** + * drm_dp_pcon_hdmi_link_active() - check if the PCON HDMI LINK status is active. + * @aux: DisplayPort AUX channel + * + * Returns true if link is active else returns false. + */ +bool drm_dp_pcon_hdmi_link_active(struct drm_dp_aux *aux) +{ + u8 buf; + int ret; + + ret = drm_dp_dpcd_readb(aux, DP_PCON_HDMI_TX_LINK_STATUS, &buf); + if (ret < 0) + return false; + + return buf & DP_PCON_HDMI_TX_LINK_ACTIVE; +} +EXPORT_SYMBOL(drm_dp_pcon_hdmi_link_active); + +/** + * drm_dp_pcon_hdmi_link_mode() - get the PCON HDMI LINK MODE + * @aux: DisplayPort AUX channel + * @frl_trained_mask: pointer to store bitmask of the trained bw configuration. + * Valid only if the MODE returned is FRL. For Normal Link training mode + * only 1 of the bits will be set, but in case of Extended mode, more than + * one bits can be set. + * + * Returns the link mode : TMDS or FRL on success, else returns negative error + * code. + */ +int drm_dp_pcon_hdmi_link_mode(struct drm_dp_aux *aux, u8 *frl_trained_mask) +{ + u8 buf; + int mode; + int ret; + + ret = drm_dp_dpcd_readb(aux, DP_PCON_HDMI_POST_FRL_STATUS, &buf); + if (ret < 0) + return ret; + + mode = buf & DP_PCON_HDMI_LINK_MODE; + + if (frl_trained_mask && DP_PCON_HDMI_MODE_FRL == mode) + *frl_trained_mask = (buf & DP_PCON_HDMI_FRL_TRAINED_BW) >> 1; + + return mode; +} +EXPORT_SYMBOL(drm_dp_pcon_hdmi_link_mode); + +/** + * drm_dp_pcon_hdmi_frl_link_error_count() - print the error count per lane + * during link failure between PCON and HDMI sink + * @aux: DisplayPort AUX channel + * @connector: DRM connector + * code. + **/ + +void drm_dp_pcon_hdmi_frl_link_error_count(struct drm_dp_aux *aux, + struct drm_connector *connector) +{ + u8 buf, error_count; + int i, num_error; + struct drm_hdmi_info *hdmi = &connector->display_info.hdmi; + + for (i = 0; i < hdmi->max_lanes; i++) { + if (drm_dp_dpcd_readb(aux, DP_PCON_HDMI_ERROR_STATUS_LN0 + i, &buf) < 0) + return; + + error_count = buf & DP_PCON_HDMI_ERROR_COUNT_MASK; + switch (error_count) { + case DP_PCON_HDMI_ERROR_COUNT_HUNDRED_PLUS: + num_error = 100; + break; + case DP_PCON_HDMI_ERROR_COUNT_TEN_PLUS: + num_error = 10; + break; + case DP_PCON_HDMI_ERROR_COUNT_THREE_PLUS: + num_error = 3; + break; + default: + num_error = 0; + } + + drm_err(aux->drm_dev, "%s: More than %d errors since the last read for lane %d", + aux->name, num_error, i); + } +} +EXPORT_SYMBOL(drm_dp_pcon_hdmi_frl_link_error_count); + +/* + * drm_dp_pcon_enc_is_dsc_1_2 - Does PCON Encoder supports DSC 1.2 + * @pcon_dsc_dpcd: DSC capabilities of the PCON DSC Encoder + * + * Returns true is PCON encoder is DSC 1.2 else returns false. + */ +bool drm_dp_pcon_enc_is_dsc_1_2(const u8 pcon_dsc_dpcd[DP_PCON_DSC_ENCODER_CAP_SIZE]) +{ + u8 buf; + u8 major_v, minor_v; + + buf = pcon_dsc_dpcd[DP_PCON_DSC_VERSION - DP_PCON_DSC_ENCODER]; + major_v = (buf & DP_PCON_DSC_MAJOR_MASK) >> DP_PCON_DSC_MAJOR_SHIFT; + minor_v = (buf & DP_PCON_DSC_MINOR_MASK) >> DP_PCON_DSC_MINOR_SHIFT; + + if (major_v == 1 && minor_v == 2) + return true; + + return false; +} +EXPORT_SYMBOL(drm_dp_pcon_enc_is_dsc_1_2); + +/* + * drm_dp_pcon_dsc_max_slices - Get max slices supported by PCON DSC Encoder + * @pcon_dsc_dpcd: DSC capabilities of the PCON DSC Encoder + * + * Returns maximum no. of slices supported by the PCON DSC Encoder. + */ +int drm_dp_pcon_dsc_max_slices(const u8 pcon_dsc_dpcd[DP_PCON_DSC_ENCODER_CAP_SIZE]) +{ + u8 slice_cap1, slice_cap2; + + slice_cap1 = pcon_dsc_dpcd[DP_PCON_DSC_SLICE_CAP_1 - DP_PCON_DSC_ENCODER]; + slice_cap2 = pcon_dsc_dpcd[DP_PCON_DSC_SLICE_CAP_2 - DP_PCON_DSC_ENCODER]; + + if (slice_cap2 & DP_PCON_DSC_24_PER_DSC_ENC) + return 24; + if (slice_cap2 & DP_PCON_DSC_20_PER_DSC_ENC) + return 20; + if (slice_cap2 & DP_PCON_DSC_16_PER_DSC_ENC) + return 16; + if (slice_cap1 & DP_PCON_DSC_12_PER_DSC_ENC) + return 12; + if (slice_cap1 & DP_PCON_DSC_10_PER_DSC_ENC) + return 10; + if (slice_cap1 & DP_PCON_DSC_8_PER_DSC_ENC) + return 8; + if (slice_cap1 & DP_PCON_DSC_6_PER_DSC_ENC) + return 6; + if (slice_cap1 & DP_PCON_DSC_4_PER_DSC_ENC) + return 4; + if (slice_cap1 & DP_PCON_DSC_2_PER_DSC_ENC) + return 2; + if (slice_cap1 & DP_PCON_DSC_1_PER_DSC_ENC) + return 1; + + return 0; +} +EXPORT_SYMBOL(drm_dp_pcon_dsc_max_slices); + +/* + * drm_dp_pcon_dsc_max_slice_width() - Get max slice width for Pcon DSC encoder + * @pcon_dsc_dpcd: DSC capabilities of the PCON DSC Encoder + * + * Returns maximum width of the slices in pixel width i.e. no. of pixels x 320. + */ +int drm_dp_pcon_dsc_max_slice_width(const u8 pcon_dsc_dpcd[DP_PCON_DSC_ENCODER_CAP_SIZE]) +{ + u8 buf; + + buf = pcon_dsc_dpcd[DP_PCON_DSC_MAX_SLICE_WIDTH - DP_PCON_DSC_ENCODER]; + + return buf * DP_DSC_SLICE_WIDTH_MULTIPLIER; +} +EXPORT_SYMBOL(drm_dp_pcon_dsc_max_slice_width); + +/* + * drm_dp_pcon_dsc_bpp_incr() - Get bits per pixel increment for PCON DSC encoder + * @pcon_dsc_dpcd: DSC capabilities of the PCON DSC Encoder + * + * Returns the bpp precision supported by the PCON encoder. + */ +int drm_dp_pcon_dsc_bpp_incr(const u8 pcon_dsc_dpcd[DP_PCON_DSC_ENCODER_CAP_SIZE]) +{ + u8 buf; + + buf = pcon_dsc_dpcd[DP_PCON_DSC_BPP_INCR - DP_PCON_DSC_ENCODER]; + + switch (buf & DP_PCON_DSC_BPP_INCR_MASK) { + case DP_PCON_DSC_ONE_16TH_BPP: + return 16; + case DP_PCON_DSC_ONE_8TH_BPP: + return 8; + case DP_PCON_DSC_ONE_4TH_BPP: + return 4; + case DP_PCON_DSC_ONE_HALF_BPP: + return 2; + case DP_PCON_DSC_ONE_BPP: + return 1; + } + + return 0; +} +EXPORT_SYMBOL(drm_dp_pcon_dsc_bpp_incr); + +static +int drm_dp_pcon_configure_dsc_enc(struct drm_dp_aux *aux, u8 pps_buf_config) +{ + u8 buf; + int ret; + + ret = drm_dp_dpcd_readb(aux, DP_PROTOCOL_CONVERTER_CONTROL_2, &buf); + if (ret < 0) + return ret; + + buf |= DP_PCON_ENABLE_DSC_ENCODER; + + if (pps_buf_config <= DP_PCON_ENC_PPS_OVERRIDE_EN_BUFFER) { + buf &= ~DP_PCON_ENCODER_PPS_OVERRIDE_MASK; + buf |= pps_buf_config << 2; + } + + ret = drm_dp_dpcd_writeb(aux, DP_PROTOCOL_CONVERTER_CONTROL_2, buf); + if (ret < 0) + return ret; + + return 0; +} + +/** + * drm_dp_pcon_pps_default() - Let PCON fill the default pps parameters + * for DSC1.2 between PCON & HDMI2.1 sink + * @aux: DisplayPort AUX channel + * + * Returns 0 on success, else returns negative error code. + */ +int drm_dp_pcon_pps_default(struct drm_dp_aux *aux) +{ + int ret; + + ret = drm_dp_pcon_configure_dsc_enc(aux, DP_PCON_ENC_PPS_OVERRIDE_DISABLED); + if (ret < 0) + return ret; + + return 0; +} +EXPORT_SYMBOL(drm_dp_pcon_pps_default); + +/** + * drm_dp_pcon_pps_override_buf() - Configure PPS encoder override buffer for + * HDMI sink + * @aux: DisplayPort AUX channel + * @pps_buf: 128 bytes to be written into PPS buffer for HDMI sink by PCON. + * + * Returns 0 on success, else returns negative error code. + */ +int drm_dp_pcon_pps_override_buf(struct drm_dp_aux *aux, u8 pps_buf[128]) +{ + int ret; + + ret = drm_dp_dpcd_write(aux, DP_PCON_HDMI_PPS_OVERRIDE_BASE, &pps_buf, 128); + if (ret < 0) + return ret; + + ret = drm_dp_pcon_configure_dsc_enc(aux, DP_PCON_ENC_PPS_OVERRIDE_EN_BUFFER); + if (ret < 0) + return ret; + + return 0; +} +EXPORT_SYMBOL(drm_dp_pcon_pps_override_buf); + +/* + * drm_dp_pcon_pps_override_param() - Write PPS parameters to DSC encoder + * override registers + * @aux: DisplayPort AUX channel + * @pps_param: 3 Parameters (2 Bytes each) : Slice Width, Slice Height, + * bits_per_pixel. + * + * Returns 0 on success, else returns negative error code. + */ +int drm_dp_pcon_pps_override_param(struct drm_dp_aux *aux, u8 pps_param[6]) +{ + int ret; + + ret = drm_dp_dpcd_write(aux, DP_PCON_HDMI_PPS_OVRD_SLICE_HEIGHT, &pps_param[0], 2); + if (ret < 0) + return ret; + ret = drm_dp_dpcd_write(aux, DP_PCON_HDMI_PPS_OVRD_SLICE_WIDTH, &pps_param[2], 2); + if (ret < 0) + return ret; + ret = drm_dp_dpcd_write(aux, DP_PCON_HDMI_PPS_OVRD_BPP, &pps_param[4], 2); + if (ret < 0) + return ret; + + ret = drm_dp_pcon_configure_dsc_enc(aux, DP_PCON_ENC_PPS_OVERRIDE_EN_BUFFER); + if (ret < 0) + return ret; + + return 0; +} +EXPORT_SYMBOL(drm_dp_pcon_pps_override_param); + +/* + * drm_dp_pcon_convert_rgb_to_ycbcr() - Configure the PCon to convert RGB to Ycbcr + * @aux: displayPort AUX channel + * @color_spc: Color-space/s for which conversion is to be enabled, 0 for disable. + * + * Returns 0 on success, else returns negative error code. + */ +int drm_dp_pcon_convert_rgb_to_ycbcr(struct drm_dp_aux *aux, u8 color_spc) +{ + int ret; + u8 buf; + + ret = drm_dp_dpcd_readb(aux, DP_PROTOCOL_CONVERTER_CONTROL_2, &buf); + if (ret < 0) + return ret; + + if (color_spc & DP_CONVERSION_RGB_YCBCR_MASK) + buf |= (color_spc & DP_CONVERSION_RGB_YCBCR_MASK); + else + buf &= ~DP_CONVERSION_RGB_YCBCR_MASK; + + ret = drm_dp_dpcd_writeb(aux, DP_PROTOCOL_CONVERTER_CONTROL_2, buf); + if (ret < 0) + return ret; + + return 0; +} +EXPORT_SYMBOL(drm_dp_pcon_convert_rgb_to_ycbcr); + +/** + * drm_edp_backlight_set_level() - Set the backlight level of an eDP panel via AUX + * @aux: The DP AUX channel to use + * @bl: Backlight capability info from drm_edp_backlight_init() + * @level: The brightness level to set + * + * Sets the brightness level of an eDP panel's backlight. Note that the panel's backlight must + * already have been enabled by the driver by calling drm_edp_backlight_enable(). + * + * Returns: %0 on success, negative error code on failure + */ +int drm_edp_backlight_set_level(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl, + u16 level) +{ + int ret; + u8 buf[2] = { 0 }; + + /* The panel uses the PWM for controlling brightness levels */ + if (!bl->aux_set) + return 0; + + if (bl->lsb_reg_used) { + buf[0] = (level & 0xff00) >> 8; + buf[1] = (level & 0x00ff); + } else { + buf[0] = level; + } + + ret = drm_dp_dpcd_write(aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, buf, sizeof(buf)); + if (ret != sizeof(buf)) { + drm_err(aux->drm_dev, + "%s: Failed to write aux backlight level: %d\n", + aux->name, ret); + return ret < 0 ? ret : -EIO; + } + + return 0; +} +EXPORT_SYMBOL(drm_edp_backlight_set_level); + +static int +drm_edp_backlight_set_enable(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl, + bool enable) +{ + int ret; + u8 buf; + + /* This panel uses the EDP_BL_PWR GPIO for enablement */ + if (!bl->aux_enable) + return 0; + + ret = drm_dp_dpcd_readb(aux, DP_EDP_DISPLAY_CONTROL_REGISTER, &buf); + if (ret != 1) { + drm_err(aux->drm_dev, "%s: Failed to read eDP display control register: %d\n", + aux->name, ret); + return ret < 0 ? ret : -EIO; + } + if (enable) + buf |= DP_EDP_BACKLIGHT_ENABLE; + else + buf &= ~DP_EDP_BACKLIGHT_ENABLE; + + ret = drm_dp_dpcd_writeb(aux, DP_EDP_DISPLAY_CONTROL_REGISTER, buf); + if (ret != 1) { + drm_err(aux->drm_dev, "%s: Failed to write eDP display control register: %d\n", + aux->name, ret); + return ret < 0 ? ret : -EIO; + } + + return 0; +} + +/** + * drm_edp_backlight_enable() - Enable an eDP panel's backlight using DPCD + * @aux: The DP AUX channel to use + * @bl: Backlight capability info from drm_edp_backlight_init() + * @level: The initial backlight level to set via AUX, if there is one + * + * This function handles enabling DPCD backlight controls on a panel over DPCD, while additionally + * restoring any important backlight state such as the given backlight level, the brightness byte + * count, backlight frequency, etc. + * + * Note that certain panels do not support being enabled or disabled via DPCD, but instead require + * that the driver handle enabling/disabling the panel through implementation-specific means using + * the EDP_BL_PWR GPIO. For such panels, &drm_edp_backlight_info.aux_enable will be set to %false, + * this function becomes a no-op, and the driver is expected to handle powering the panel on using + * the EDP_BL_PWR GPIO. + * + * Returns: %0 on success, negative error code on failure. + */ +int drm_edp_backlight_enable(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl, + const u16 level) +{ + int ret; + u8 dpcd_buf; + + if (bl->aux_set) + dpcd_buf = DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD; + else + dpcd_buf = DP_EDP_BACKLIGHT_CONTROL_MODE_PWM; + + if (bl->pwmgen_bit_count) { + ret = drm_dp_dpcd_writeb(aux, DP_EDP_PWMGEN_BIT_COUNT, bl->pwmgen_bit_count); + if (ret != 1) + drm_dbg_kms(aux->drm_dev, "%s: Failed to write aux pwmgen bit count: %d\n", + aux->name, ret); + } + + if (bl->pwm_freq_pre_divider) { + ret = drm_dp_dpcd_writeb(aux, DP_EDP_BACKLIGHT_FREQ_SET, bl->pwm_freq_pre_divider); + if (ret != 1) + drm_dbg_kms(aux->drm_dev, + "%s: Failed to write aux backlight frequency: %d\n", + aux->name, ret); + else + dpcd_buf |= DP_EDP_BACKLIGHT_FREQ_AUX_SET_ENABLE; + } + + ret = drm_dp_dpcd_writeb(aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, dpcd_buf); + if (ret != 1) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to write aux backlight mode: %d\n", + aux->name, ret); + return ret < 0 ? ret : -EIO; + } + + ret = drm_edp_backlight_set_level(aux, bl, level); + if (ret < 0) + return ret; + ret = drm_edp_backlight_set_enable(aux, bl, true); + if (ret < 0) + return ret; + + return 0; +} +EXPORT_SYMBOL(drm_edp_backlight_enable); + +/** + * drm_edp_backlight_disable() - Disable an eDP backlight using DPCD, if supported + * @aux: The DP AUX channel to use + * @bl: Backlight capability info from drm_edp_backlight_init() + * + * This function handles disabling DPCD backlight controls on a panel over AUX. + * + * Note that certain panels do not support being enabled or disabled via DPCD, but instead require + * that the driver handle enabling/disabling the panel through implementation-specific means using + * the EDP_BL_PWR GPIO. For such panels, &drm_edp_backlight_info.aux_enable will be set to %false, + * this function becomes a no-op, and the driver is expected to handle powering the panel off using + * the EDP_BL_PWR GPIO. + * + * Returns: %0 on success or no-op, negative error code on failure. + */ +int drm_edp_backlight_disable(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl) +{ + int ret; + + ret = drm_edp_backlight_set_enable(aux, bl, false); + if (ret < 0) + return ret; + + return 0; +} +EXPORT_SYMBOL(drm_edp_backlight_disable); + +static inline int +drm_edp_backlight_probe_max(struct drm_dp_aux *aux, struct drm_edp_backlight_info *bl, + u16 driver_pwm_freq_hz, const u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE]) +{ + int fxp, fxp_min, fxp_max, fxp_actual, f = 1; + int ret; + u8 pn, pn_min, pn_max; + + if (!bl->aux_set) + return 0; + + ret = drm_dp_dpcd_readb(aux, DP_EDP_PWMGEN_BIT_COUNT, &pn); + if (ret != 1) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to read pwmgen bit count cap: %d\n", + aux->name, ret); + return -ENODEV; + } + + pn &= DP_EDP_PWMGEN_BIT_COUNT_MASK; + bl->max = (1 << pn) - 1; + if (!driver_pwm_freq_hz) + return 0; + + /* + * Set PWM Frequency divider to match desired frequency provided by the driver. + * The PWM Frequency is calculated as 27Mhz / (F x P). + * - Where F = PWM Frequency Pre-Divider value programmed by field 7:0 of the + * EDP_BACKLIGHT_FREQ_SET register (DPCD Address 00728h) + * - Where P = 2^Pn, where Pn is the value programmed by field 4:0 of the + * EDP_PWMGEN_BIT_COUNT register (DPCD Address 00724h) + */ + + /* Find desired value of (F x P) + * Note that, if F x P is out of supported range, the maximum value or minimum value will + * applied automatically. So no need to check that. + */ + fxp = DIV_ROUND_CLOSEST(1000 * DP_EDP_BACKLIGHT_FREQ_BASE_KHZ, driver_pwm_freq_hz); + + /* Use highest possible value of Pn for more granularity of brightness adjustment while + * satisfying the conditions below. + * - Pn is in the range of Pn_min and Pn_max + * - F is in the range of 1 and 255 + * - FxP is within 25% of desired value. + * Note: 25% is arbitrary value and may need some tweak. + */ + ret = drm_dp_dpcd_readb(aux, DP_EDP_PWMGEN_BIT_COUNT_CAP_MIN, &pn_min); + if (ret != 1) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to read pwmgen bit count cap min: %d\n", + aux->name, ret); + return 0; + } + ret = drm_dp_dpcd_readb(aux, DP_EDP_PWMGEN_BIT_COUNT_CAP_MAX, &pn_max); + if (ret != 1) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to read pwmgen bit count cap max: %d\n", + aux->name, ret); + return 0; + } + pn_min &= DP_EDP_PWMGEN_BIT_COUNT_MASK; + pn_max &= DP_EDP_PWMGEN_BIT_COUNT_MASK; + + /* Ensure frequency is within 25% of desired value */ + fxp_min = DIV_ROUND_CLOSEST(fxp * 3, 4); + fxp_max = DIV_ROUND_CLOSEST(fxp * 5, 4); + if (fxp_min < (1 << pn_min) || (255 << pn_max) < fxp_max) { + drm_dbg_kms(aux->drm_dev, + "%s: Driver defined backlight frequency (%d) out of range\n", + aux->name, driver_pwm_freq_hz); + return 0; + } + + for (pn = pn_max; pn >= pn_min; pn--) { + f = clamp(DIV_ROUND_CLOSEST(fxp, 1 << pn), 1, 255); + fxp_actual = f << pn; + if (fxp_min <= fxp_actual && fxp_actual <= fxp_max) + break; + } + + ret = drm_dp_dpcd_writeb(aux, DP_EDP_PWMGEN_BIT_COUNT, pn); + if (ret != 1) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to write aux pwmgen bit count: %d\n", + aux->name, ret); + return 0; + } + bl->pwmgen_bit_count = pn; + bl->max = (1 << pn) - 1; + + if (edp_dpcd[2] & DP_EDP_BACKLIGHT_FREQ_AUX_SET_CAP) { + bl->pwm_freq_pre_divider = f; + drm_dbg_kms(aux->drm_dev, "%s: Using backlight frequency from driver (%dHz)\n", + aux->name, driver_pwm_freq_hz); + } + + return 0; +} + +static inline int +drm_edp_backlight_probe_state(struct drm_dp_aux *aux, struct drm_edp_backlight_info *bl, + u8 *current_mode) +{ + int ret; + u8 buf[2]; + u8 mode_reg; + + ret = drm_dp_dpcd_readb(aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, &mode_reg); + if (ret != 1) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to read backlight mode: %d\n", + aux->name, ret); + return ret < 0 ? ret : -EIO; + } + + *current_mode = (mode_reg & DP_EDP_BACKLIGHT_CONTROL_MODE_MASK); + if (!bl->aux_set) + return 0; + + if (*current_mode == DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) { + int size = 1 + bl->lsb_reg_used; + + ret = drm_dp_dpcd_read(aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, buf, size); + if (ret != size) { + drm_dbg_kms(aux->drm_dev, "%s: Failed to read backlight level: %d\n", + aux->name, ret); + return ret < 0 ? ret : -EIO; + } + + if (bl->lsb_reg_used) + return (buf[0] << 8) | buf[1]; + else + return buf[0]; + } + + /* + * If we're not in DPCD control mode yet, the programmed brightness value is meaningless and + * the driver should assume max brightness + */ + return bl->max; +} + +/** + * drm_edp_backlight_init() - Probe a display panel's TCON using the standard VESA eDP backlight + * interface. + * @aux: The DP aux device to use for probing + * @bl: The &drm_edp_backlight_info struct to fill out with information on the backlight + * @driver_pwm_freq_hz: Optional PWM frequency from the driver in hz + * @edp_dpcd: A cached copy of the eDP DPCD + * @current_level: Where to store the probed brightness level, if any + * @current_mode: Where to store the currently set backlight control mode + * + * Initializes a &drm_edp_backlight_info struct by probing @aux for it's backlight capabilities, + * along with also probing the current and maximum supported brightness levels. + * + * If @driver_pwm_freq_hz is non-zero, this will be used as the backlight frequency. Otherwise, the + * default frequency from the panel is used. + * + * Returns: %0 on success, negative error code on failure. + */ +int +drm_edp_backlight_init(struct drm_dp_aux *aux, struct drm_edp_backlight_info *bl, + u16 driver_pwm_freq_hz, const u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE], + u16 *current_level, u8 *current_mode) +{ + int ret; + + if (edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP) + bl->aux_enable = true; + if (edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP) + bl->aux_set = true; + if (edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_BYTE_COUNT) + bl->lsb_reg_used = true; + + /* Sanity check caps */ + if (!bl->aux_set && !(edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_PWM_PIN_CAP)) { + drm_dbg_kms(aux->drm_dev, + "%s: Panel supports neither AUX or PWM brightness control? Aborting\n", + aux->name); + return -EINVAL; + } + + ret = drm_edp_backlight_probe_max(aux, bl, driver_pwm_freq_hz, edp_dpcd); + if (ret < 0) + return ret; + + ret = drm_edp_backlight_probe_state(aux, bl, current_mode); + if (ret < 0) + return ret; + *current_level = ret; + + drm_dbg_kms(aux->drm_dev, + "%s: Found backlight: aux_set=%d aux_enable=%d mode=%d\n", + aux->name, bl->aux_set, bl->aux_enable, *current_mode); + if (bl->aux_set) { + drm_dbg_kms(aux->drm_dev, + "%s: Backlight caps: level=%d/%d pwm_freq_pre_divider=%d lsb_reg_used=%d\n", + aux->name, *current_level, bl->max, bl->pwm_freq_pre_divider, + bl->lsb_reg_used); + } + + return 0; +} +EXPORT_SYMBOL(drm_edp_backlight_init); + +#if IS_BUILTIN(CONFIG_BACKLIGHT_CLASS_DEVICE) || \ + (IS_MODULE(CONFIG_DRM_KMS_HELPER) && IS_MODULE(CONFIG_BACKLIGHT_CLASS_DEVICE)) + +static int dp_aux_backlight_update_status(struct backlight_device *bd) +{ + struct dp_aux_backlight *bl = bl_get_data(bd); + u16 brightness = backlight_get_brightness(bd); + int ret = 0; + + if (!backlight_is_blank(bd)) { + if (!bl->enabled) { + drm_edp_backlight_enable(bl->aux, &bl->info, brightness); + bl->enabled = true; + return 0; + } + ret = drm_edp_backlight_set_level(bl->aux, &bl->info, brightness); + } else { + if (bl->enabled) { + drm_edp_backlight_disable(bl->aux, &bl->info); + bl->enabled = false; + } + } + + return ret; +} + +static const struct backlight_ops dp_aux_bl_ops = { + .update_status = dp_aux_backlight_update_status, +}; + +/** + * drm_panel_dp_aux_backlight - create and use DP AUX backlight + * @panel: DRM panel + * @aux: The DP AUX channel to use + * + * Use this function to create and handle backlight if your panel + * supports backlight control over DP AUX channel using DPCD + * registers as per VESA's standard backlight control interface. + * + * When the panel is enabled backlight will be enabled after a + * successful call to &drm_panel_funcs.enable() + * + * When the panel is disabled backlight will be disabled before the + * call to &drm_panel_funcs.disable(). + * + * A typical implementation for a panel driver supporting backlight + * control over DP AUX will call this function at probe time. + * Backlight will then be handled transparently without requiring + * any intervention from the driver. + * + * drm_panel_dp_aux_backlight() must be called after the call to drm_panel_init(). + * + * Return: 0 on success or a negative error code on failure. + */ +int drm_panel_dp_aux_backlight(struct drm_panel *panel, struct drm_dp_aux *aux) +{ + struct dp_aux_backlight *bl; + struct backlight_properties props = { 0 }; + u16 current_level; + u8 current_mode; + u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE]; + int ret; + + if (!panel || !panel->dev || !aux) + return -EINVAL; + + ret = drm_dp_dpcd_read(aux, DP_EDP_DPCD_REV, edp_dpcd, + EDP_DISPLAY_CTL_CAP_SIZE); + if (ret < 0) + return ret; + + if (!drm_edp_backlight_supported(edp_dpcd)) { + DRM_DEV_INFO(panel->dev, "DP AUX backlight is not supported\n"); + return 0; + } + + bl = devm_kzalloc(panel->dev, sizeof(*bl), GFP_KERNEL); + if (!bl) + return -ENOMEM; + + bl->aux = aux; + + ret = drm_edp_backlight_init(aux, &bl->info, 0, edp_dpcd, + ¤t_level, ¤t_mode); + if (ret < 0) + return ret; + + props.type = BACKLIGHT_RAW; + props.brightness = current_level; + props.max_brightness = bl->info.max; + + bl->base = devm_backlight_device_register(panel->dev, "dp_aux_backlight", + panel->dev, bl, + &dp_aux_bl_ops, &props); + if (IS_ERR(bl->base)) + return PTR_ERR(bl->base); + + backlight_disable(bl->base); + + panel->backlight = bl->base; + + return 0; +} +EXPORT_SYMBOL(drm_panel_dp_aux_backlight); + +#endif diff --git a/drivers/gpu/drm/display/drm_dp_helper_internal.h b/drivers/gpu/drm/display/drm_dp_helper_internal.h new file mode 100644 index 000000000..8917fc3af --- /dev/null +++ b/drivers/gpu/drm/display/drm_dp_helper_internal.h @@ -0,0 +1,33 @@ +/* SPDX-License-Identifier: MIT */ + +#ifndef DRM_DP_HELPER_INTERNAL_H +#define DRM_DP_HELPER_INTERNAL_H + +struct drm_dp_aux; + +#ifdef CONFIG_DRM_DP_AUX_CHARDEV +int drm_dp_aux_dev_init(void); +void drm_dp_aux_dev_exit(void); +int drm_dp_aux_register_devnode(struct drm_dp_aux *aux); +void drm_dp_aux_unregister_devnode(struct drm_dp_aux *aux); +#else +static inline int drm_dp_aux_dev_init(void) +{ + return 0; +} + +static inline void drm_dp_aux_dev_exit(void) +{ +} + +static inline int drm_dp_aux_register_devnode(struct drm_dp_aux *aux) +{ + return 0; +} + +static inline void drm_dp_aux_unregister_devnode(struct drm_dp_aux *aux) +{ +} +#endif + +#endif diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c new file mode 100644 index 000000000..72b2b171e --- /dev/null +++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c @@ -0,0 +1,5929 @@ +/* + * Copyright © 2014 Red Hat + * + * Permission to use, copy, modify, distribute, and sell this software and its + * documentation for any purpose is hereby granted without fee, provided that + * the above copyright notice appear in all copies and that both that copyright + * notice and this permission notice appear in supporting documentation, and + * that the name of the copyright holders not be used in advertising or + * publicity pertaining to distribution of the software without specific, + * written prior permission. The copyright holders make no representations + * about the suitability of this software for any purpose. It is provided "as + * is" without express or implied warranty. + * + * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, + * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO + * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR + * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, + * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER + * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE + * OF THIS SOFTWARE. + */ + +#include <linux/bitfield.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/random.h> +#include <linux/sched.h> +#include <linux/seq_file.h> +#include <linux/iopoll.h> + +#if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS) +#include <linux/stacktrace.h> +#include <linux/sort.h> +#include <linux/timekeeping.h> +#include <linux/math64.h> +#endif + +#include <drm/display/drm_dp_mst_helper.h> +#include <drm/drm_atomic.h> +#include <drm/drm_atomic_helper.h> +#include <drm/drm_drv.h> +#include <drm/drm_edid.h> +#include <drm/drm_print.h> +#include <drm/drm_probe_helper.h> + +#include "drm_dp_helper_internal.h" +#include "drm_dp_mst_topology_internal.h" + +/** + * DOC: dp mst helper + * + * These functions contain parts of the DisplayPort 1.2a MultiStream Transport + * protocol. The helpers contain a topology manager and bandwidth manager. + * The helpers encapsulate the sending and received of sideband msgs. + */ +struct drm_dp_pending_up_req { + struct drm_dp_sideband_msg_hdr hdr; + struct drm_dp_sideband_msg_req_body msg; + struct list_head next; +}; + +static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr, + char *buf); + +static void drm_dp_mst_topology_put_port(struct drm_dp_mst_port *port); + +static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr, + int id, u8 start_slot, u8 num_slots); + +static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port, + int offset, int size, u8 *bytes); +static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port, + int offset, int size, u8 *bytes); + +static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_branch *mstb); + +static void +drm_dp_send_clear_payload_id_table(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_branch *mstb); + +static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_branch *mstb, + struct drm_dp_mst_port *port); +static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr, + u8 *guid); + +static int drm_dp_mst_register_i2c_bus(struct drm_dp_mst_port *port); +static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_mst_port *port); +static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr); + +static bool drm_dp_mst_port_downstream_of_branch(struct drm_dp_mst_port *port, + struct drm_dp_mst_branch *branch); + +#define DBG_PREFIX "[dp_mst]" + +#define DP_STR(x) [DP_ ## x] = #x + +static const char *drm_dp_mst_req_type_str(u8 req_type) +{ + static const char * const req_type_str[] = { + DP_STR(GET_MSG_TRANSACTION_VERSION), + DP_STR(LINK_ADDRESS), + DP_STR(CONNECTION_STATUS_NOTIFY), + DP_STR(ENUM_PATH_RESOURCES), + DP_STR(ALLOCATE_PAYLOAD), + DP_STR(QUERY_PAYLOAD), + DP_STR(RESOURCE_STATUS_NOTIFY), + DP_STR(CLEAR_PAYLOAD_ID_TABLE), + DP_STR(REMOTE_DPCD_READ), + DP_STR(REMOTE_DPCD_WRITE), + DP_STR(REMOTE_I2C_READ), + DP_STR(REMOTE_I2C_WRITE), + DP_STR(POWER_UP_PHY), + DP_STR(POWER_DOWN_PHY), + DP_STR(SINK_EVENT_NOTIFY), + DP_STR(QUERY_STREAM_ENC_STATUS), + }; + + if (req_type >= ARRAY_SIZE(req_type_str) || + !req_type_str[req_type]) + return "unknown"; + + return req_type_str[req_type]; +} + +#undef DP_STR +#define DP_STR(x) [DP_NAK_ ## x] = #x + +static const char *drm_dp_mst_nak_reason_str(u8 nak_reason) +{ + static const char * const nak_reason_str[] = { + DP_STR(WRITE_FAILURE), + DP_STR(INVALID_READ), + DP_STR(CRC_FAILURE), + DP_STR(BAD_PARAM), + DP_STR(DEFER), + DP_STR(LINK_FAILURE), + DP_STR(NO_RESOURCES), + DP_STR(DPCD_FAIL), + DP_STR(I2C_NAK), + DP_STR(ALLOCATE_FAIL), + }; + + if (nak_reason >= ARRAY_SIZE(nak_reason_str) || + !nak_reason_str[nak_reason]) + return "unknown"; + + return nak_reason_str[nak_reason]; +} + +#undef DP_STR +#define DP_STR(x) [DRM_DP_SIDEBAND_TX_ ## x] = #x + +static const char *drm_dp_mst_sideband_tx_state_str(int state) +{ + static const char * const sideband_reason_str[] = { + DP_STR(QUEUED), + DP_STR(START_SEND), + DP_STR(SENT), + DP_STR(RX), + DP_STR(TIMEOUT), + }; + + if (state >= ARRAY_SIZE(sideband_reason_str) || + !sideband_reason_str[state]) + return "unknown"; + + return sideband_reason_str[state]; +} + +static int +drm_dp_mst_rad_to_str(const u8 rad[8], u8 lct, char *out, size_t len) +{ + int i; + u8 unpacked_rad[16]; + + for (i = 0; i < lct; i++) { + if (i % 2) + unpacked_rad[i] = rad[i / 2] >> 4; + else + unpacked_rad[i] = rad[i / 2] & BIT_MASK(4); + } + + /* TODO: Eventually add something to printk so we can format the rad + * like this: 1.2.3 + */ + return snprintf(out, len, "%*phC", lct, unpacked_rad); +} + +/* sideband msg handling */ +static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles) +{ + u8 bitmask = 0x80; + u8 bitshift = 7; + u8 array_index = 0; + int number_of_bits = num_nibbles * 4; + u8 remainder = 0; + + while (number_of_bits != 0) { + number_of_bits--; + remainder <<= 1; + remainder |= (data[array_index] & bitmask) >> bitshift; + bitmask >>= 1; + bitshift--; + if (bitmask == 0) { + bitmask = 0x80; + bitshift = 7; + array_index++; + } + if ((remainder & 0x10) == 0x10) + remainder ^= 0x13; + } + + number_of_bits = 4; + while (number_of_bits != 0) { + number_of_bits--; + remainder <<= 1; + if ((remainder & 0x10) != 0) + remainder ^= 0x13; + } + + return remainder; +} + +static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes) +{ + u8 bitmask = 0x80; + u8 bitshift = 7; + u8 array_index = 0; + int number_of_bits = number_of_bytes * 8; + u16 remainder = 0; + + while (number_of_bits != 0) { + number_of_bits--; + remainder <<= 1; + remainder |= (data[array_index] & bitmask) >> bitshift; + bitmask >>= 1; + bitshift--; + if (bitmask == 0) { + bitmask = 0x80; + bitshift = 7; + array_index++; + } + if ((remainder & 0x100) == 0x100) + remainder ^= 0xd5; + } + + number_of_bits = 8; + while (number_of_bits != 0) { + number_of_bits--; + remainder <<= 1; + if ((remainder & 0x100) != 0) + remainder ^= 0xd5; + } + + return remainder & 0xff; +} +static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr) +{ + u8 size = 3; + + size += (hdr->lct / 2); + return size; +} + +static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr, + u8 *buf, int *len) +{ + int idx = 0; + int i; + u8 crc4; + + buf[idx++] = ((hdr->lct & 0xf) << 4) | (hdr->lcr & 0xf); + for (i = 0; i < (hdr->lct / 2); i++) + buf[idx++] = hdr->rad[i]; + buf[idx++] = (hdr->broadcast << 7) | (hdr->path_msg << 6) | + (hdr->msg_len & 0x3f); + buf[idx++] = (hdr->somt << 7) | (hdr->eomt << 6) | (hdr->seqno << 4); + + crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1); + buf[idx - 1] |= (crc4 & 0xf); + + *len = idx; +} + +static bool drm_dp_decode_sideband_msg_hdr(const struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_sideband_msg_hdr *hdr, + u8 *buf, int buflen, u8 *hdrlen) +{ + u8 crc4; + u8 len; + int i; + u8 idx; + + if (buf[0] == 0) + return false; + len = 3; + len += ((buf[0] & 0xf0) >> 4) / 2; + if (len > buflen) + return false; + crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1); + + if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) { + drm_dbg_kms(mgr->dev, "crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]); + return false; + } + + hdr->lct = (buf[0] & 0xf0) >> 4; + hdr->lcr = (buf[0] & 0xf); + idx = 1; + for (i = 0; i < (hdr->lct / 2); i++) + hdr->rad[i] = buf[idx++]; + hdr->broadcast = (buf[idx] >> 7) & 0x1; + hdr->path_msg = (buf[idx] >> 6) & 0x1; + hdr->msg_len = buf[idx] & 0x3f; + idx++; + hdr->somt = (buf[idx] >> 7) & 0x1; + hdr->eomt = (buf[idx] >> 6) & 0x1; + hdr->seqno = (buf[idx] >> 4) & 0x1; + idx++; + *hdrlen = idx; + return true; +} + +void +drm_dp_encode_sideband_req(const struct drm_dp_sideband_msg_req_body *req, + struct drm_dp_sideband_msg_tx *raw) +{ + int idx = 0; + int i; + u8 *buf = raw->msg; + + buf[idx++] = req->req_type & 0x7f; + + switch (req->req_type) { + case DP_ENUM_PATH_RESOURCES: + case DP_POWER_DOWN_PHY: + case DP_POWER_UP_PHY: + buf[idx] = (req->u.port_num.port_number & 0xf) << 4; + idx++; + break; + case DP_ALLOCATE_PAYLOAD: + buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 | + (req->u.allocate_payload.number_sdp_streams & 0xf); + idx++; + buf[idx] = (req->u.allocate_payload.vcpi & 0x7f); + idx++; + buf[idx] = (req->u.allocate_payload.pbn >> 8); + idx++; + buf[idx] = (req->u.allocate_payload.pbn & 0xff); + idx++; + for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) { + buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) | + (req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf); + idx++; + } + if (req->u.allocate_payload.number_sdp_streams & 1) { + i = req->u.allocate_payload.number_sdp_streams - 1; + buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4; + idx++; + } + break; + case DP_QUERY_PAYLOAD: + buf[idx] = (req->u.query_payload.port_number & 0xf) << 4; + idx++; + buf[idx] = (req->u.query_payload.vcpi & 0x7f); + idx++; + break; + case DP_REMOTE_DPCD_READ: + buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4; + buf[idx] |= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf; + idx++; + buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8; + idx++; + buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff); + idx++; + buf[idx] = (req->u.dpcd_read.num_bytes); + idx++; + break; + + case DP_REMOTE_DPCD_WRITE: + buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4; + buf[idx] |= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf; + idx++; + buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8; + idx++; + buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff); + idx++; + buf[idx] = (req->u.dpcd_write.num_bytes); + idx++; + memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes); + idx += req->u.dpcd_write.num_bytes; + break; + case DP_REMOTE_I2C_READ: + buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4; + buf[idx] |= (req->u.i2c_read.num_transactions & 0x3); + idx++; + for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) { + buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f; + idx++; + buf[idx] = req->u.i2c_read.transactions[i].num_bytes; + idx++; + memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes); + idx += req->u.i2c_read.transactions[i].num_bytes; + + buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 4; + buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf); + idx++; + } + buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f; + idx++; + buf[idx] = (req->u.i2c_read.num_bytes_read); + idx++; + break; + + case DP_REMOTE_I2C_WRITE: + buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4; + idx++; + buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f; + idx++; + buf[idx] = (req->u.i2c_write.num_bytes); + idx++; + memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes); + idx += req->u.i2c_write.num_bytes; + break; + case DP_QUERY_STREAM_ENC_STATUS: { + const struct drm_dp_query_stream_enc_status *msg; + + msg = &req->u.enc_status; + buf[idx] = msg->stream_id; + idx++; + memcpy(&buf[idx], msg->client_id, sizeof(msg->client_id)); + idx += sizeof(msg->client_id); + buf[idx] = 0; + buf[idx] |= FIELD_PREP(GENMASK(1, 0), msg->stream_event); + buf[idx] |= msg->valid_stream_event ? BIT(2) : 0; + buf[idx] |= FIELD_PREP(GENMASK(4, 3), msg->stream_behavior); + buf[idx] |= msg->valid_stream_behavior ? BIT(5) : 0; + idx++; + } + break; + } + raw->cur_len = idx; +} +EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_dp_encode_sideband_req); + +/* Decode a sideband request we've encoded, mainly used for debugging */ +int +drm_dp_decode_sideband_req(const struct drm_dp_sideband_msg_tx *raw, + struct drm_dp_sideband_msg_req_body *req) +{ + const u8 *buf = raw->msg; + int i, idx = 0; + + req->req_type = buf[idx++] & 0x7f; + switch (req->req_type) { + case DP_ENUM_PATH_RESOURCES: + case DP_POWER_DOWN_PHY: + case DP_POWER_UP_PHY: + req->u.port_num.port_number = (buf[idx] >> 4) & 0xf; + break; + case DP_ALLOCATE_PAYLOAD: + { + struct drm_dp_allocate_payload *a = + &req->u.allocate_payload; + + a->number_sdp_streams = buf[idx] & 0xf; + a->port_number = (buf[idx] >> 4) & 0xf; + + WARN_ON(buf[++idx] & 0x80); + a->vcpi = buf[idx] & 0x7f; + + a->pbn = buf[++idx] << 8; + a->pbn |= buf[++idx]; + + idx++; + for (i = 0; i < a->number_sdp_streams; i++) { + a->sdp_stream_sink[i] = + (buf[idx + (i / 2)] >> ((i % 2) ? 0 : 4)) & 0xf; + } + } + break; + case DP_QUERY_PAYLOAD: + req->u.query_payload.port_number = (buf[idx] >> 4) & 0xf; + WARN_ON(buf[++idx] & 0x80); + req->u.query_payload.vcpi = buf[idx] & 0x7f; + break; + case DP_REMOTE_DPCD_READ: + { + struct drm_dp_remote_dpcd_read *r = &req->u.dpcd_read; + + r->port_number = (buf[idx] >> 4) & 0xf; + + r->dpcd_address = (buf[idx] << 16) & 0xf0000; + r->dpcd_address |= (buf[++idx] << 8) & 0xff00; + r->dpcd_address |= buf[++idx] & 0xff; + + r->num_bytes = buf[++idx]; + } + break; + case DP_REMOTE_DPCD_WRITE: + { + struct drm_dp_remote_dpcd_write *w = + &req->u.dpcd_write; + + w->port_number = (buf[idx] >> 4) & 0xf; + + w->dpcd_address = (buf[idx] << 16) & 0xf0000; + w->dpcd_address |= (buf[++idx] << 8) & 0xff00; + w->dpcd_address |= buf[++idx] & 0xff; + + w->num_bytes = buf[++idx]; + + w->bytes = kmemdup(&buf[++idx], w->num_bytes, + GFP_KERNEL); + if (!w->bytes) + return -ENOMEM; + } + break; + case DP_REMOTE_I2C_READ: + { + struct drm_dp_remote_i2c_read *r = &req->u.i2c_read; + struct drm_dp_remote_i2c_read_tx *tx; + bool failed = false; + + r->num_transactions = buf[idx] & 0x3; + r->port_number = (buf[idx] >> 4) & 0xf; + for (i = 0; i < r->num_transactions; i++) { + tx = &r->transactions[i]; + + tx->i2c_dev_id = buf[++idx] & 0x7f; + tx->num_bytes = buf[++idx]; + tx->bytes = kmemdup(&buf[++idx], + tx->num_bytes, + GFP_KERNEL); + if (!tx->bytes) { + failed = true; + break; + } + idx += tx->num_bytes; + tx->no_stop_bit = (buf[idx] >> 5) & 0x1; + tx->i2c_transaction_delay = buf[idx] & 0xf; + } + + if (failed) { + for (i = 0; i < r->num_transactions; i++) { + tx = &r->transactions[i]; + kfree(tx->bytes); + } + return -ENOMEM; + } + + r->read_i2c_device_id = buf[++idx] & 0x7f; + r->num_bytes_read = buf[++idx]; + } + break; + case DP_REMOTE_I2C_WRITE: + { + struct drm_dp_remote_i2c_write *w = &req->u.i2c_write; + + w->port_number = (buf[idx] >> 4) & 0xf; + w->write_i2c_device_id = buf[++idx] & 0x7f; + w->num_bytes = buf[++idx]; + w->bytes = kmemdup(&buf[++idx], w->num_bytes, + GFP_KERNEL); + if (!w->bytes) + return -ENOMEM; + } + break; + case DP_QUERY_STREAM_ENC_STATUS: + req->u.enc_status.stream_id = buf[idx++]; + for (i = 0; i < sizeof(req->u.enc_status.client_id); i++) + req->u.enc_status.client_id[i] = buf[idx++]; + + req->u.enc_status.stream_event = FIELD_GET(GENMASK(1, 0), + buf[idx]); + req->u.enc_status.valid_stream_event = FIELD_GET(BIT(2), + buf[idx]); + req->u.enc_status.stream_behavior = FIELD_GET(GENMASK(4, 3), + buf[idx]); + req->u.enc_status.valid_stream_behavior = FIELD_GET(BIT(5), + buf[idx]); + break; + } + + return 0; +} +EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_dp_decode_sideband_req); + +void +drm_dp_dump_sideband_msg_req_body(const struct drm_dp_sideband_msg_req_body *req, + int indent, struct drm_printer *printer) +{ + int i; + +#define P(f, ...) drm_printf_indent(printer, indent, f, ##__VA_ARGS__) + if (req->req_type == DP_LINK_ADDRESS) { + /* No contents to print */ + P("type=%s\n", drm_dp_mst_req_type_str(req->req_type)); + return; + } + + P("type=%s contents:\n", drm_dp_mst_req_type_str(req->req_type)); + indent++; + + switch (req->req_type) { + case DP_ENUM_PATH_RESOURCES: + case DP_POWER_DOWN_PHY: + case DP_POWER_UP_PHY: + P("port=%d\n", req->u.port_num.port_number); + break; + case DP_ALLOCATE_PAYLOAD: + P("port=%d vcpi=%d pbn=%d sdp_streams=%d %*ph\n", + req->u.allocate_payload.port_number, + req->u.allocate_payload.vcpi, req->u.allocate_payload.pbn, + req->u.allocate_payload.number_sdp_streams, + req->u.allocate_payload.number_sdp_streams, + req->u.allocate_payload.sdp_stream_sink); + break; + case DP_QUERY_PAYLOAD: + P("port=%d vcpi=%d\n", + req->u.query_payload.port_number, + req->u.query_payload.vcpi); + break; + case DP_REMOTE_DPCD_READ: + P("port=%d dpcd_addr=%05x len=%d\n", + req->u.dpcd_read.port_number, req->u.dpcd_read.dpcd_address, + req->u.dpcd_read.num_bytes); + break; + case DP_REMOTE_DPCD_WRITE: + P("port=%d addr=%05x len=%d: %*ph\n", + req->u.dpcd_write.port_number, + req->u.dpcd_write.dpcd_address, + req->u.dpcd_write.num_bytes, req->u.dpcd_write.num_bytes, + req->u.dpcd_write.bytes); + break; + case DP_REMOTE_I2C_READ: + P("port=%d num_tx=%d id=%d size=%d:\n", + req->u.i2c_read.port_number, + req->u.i2c_read.num_transactions, + req->u.i2c_read.read_i2c_device_id, + req->u.i2c_read.num_bytes_read); + + indent++; + for (i = 0; i < req->u.i2c_read.num_transactions; i++) { + const struct drm_dp_remote_i2c_read_tx *rtx = + &req->u.i2c_read.transactions[i]; + + P("%d: id=%03d size=%03d no_stop_bit=%d tx_delay=%03d: %*ph\n", + i, rtx->i2c_dev_id, rtx->num_bytes, + rtx->no_stop_bit, rtx->i2c_transaction_delay, + rtx->num_bytes, rtx->bytes); + } + break; + case DP_REMOTE_I2C_WRITE: + P("port=%d id=%d size=%d: %*ph\n", + req->u.i2c_write.port_number, + req->u.i2c_write.write_i2c_device_id, + req->u.i2c_write.num_bytes, req->u.i2c_write.num_bytes, + req->u.i2c_write.bytes); + break; + case DP_QUERY_STREAM_ENC_STATUS: + P("stream_id=%u client_id=%*ph stream_event=%x " + "valid_event=%d stream_behavior=%x valid_behavior=%d", + req->u.enc_status.stream_id, + (int)ARRAY_SIZE(req->u.enc_status.client_id), + req->u.enc_status.client_id, req->u.enc_status.stream_event, + req->u.enc_status.valid_stream_event, + req->u.enc_status.stream_behavior, + req->u.enc_status.valid_stream_behavior); + break; + default: + P("???\n"); + break; + } +#undef P +} +EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_dp_dump_sideband_msg_req_body); + +static inline void +drm_dp_mst_dump_sideband_msg_tx(struct drm_printer *p, + const struct drm_dp_sideband_msg_tx *txmsg) +{ + struct drm_dp_sideband_msg_req_body req; + char buf[64]; + int ret; + int i; + + drm_dp_mst_rad_to_str(txmsg->dst->rad, txmsg->dst->lct, buf, + sizeof(buf)); + drm_printf(p, "txmsg cur_offset=%x cur_len=%x seqno=%x state=%s path_msg=%d dst=%s\n", + txmsg->cur_offset, txmsg->cur_len, txmsg->seqno, + drm_dp_mst_sideband_tx_state_str(txmsg->state), + txmsg->path_msg, buf); + + ret = drm_dp_decode_sideband_req(txmsg, &req); + if (ret) { + drm_printf(p, "<failed to decode sideband req: %d>\n", ret); + return; + } + drm_dp_dump_sideband_msg_req_body(&req, 1, p); + + switch (req.req_type) { + case DP_REMOTE_DPCD_WRITE: + kfree(req.u.dpcd_write.bytes); + break; + case DP_REMOTE_I2C_READ: + for (i = 0; i < req.u.i2c_read.num_transactions; i++) + kfree(req.u.i2c_read.transactions[i].bytes); + break; + case DP_REMOTE_I2C_WRITE: + kfree(req.u.i2c_write.bytes); + break; + } +} + +static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len) +{ + u8 crc4; + + crc4 = drm_dp_msg_data_crc4(msg, len); + msg[len] = crc4; +} + +static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep, + struct drm_dp_sideband_msg_tx *raw) +{ + int idx = 0; + u8 *buf = raw->msg; + + buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f); + + raw->cur_len = idx; +} + +static int drm_dp_sideband_msg_set_header(struct drm_dp_sideband_msg_rx *msg, + struct drm_dp_sideband_msg_hdr *hdr, + u8 hdrlen) +{ + /* + * ignore out-of-order messages or messages that are part of a + * failed transaction + */ + if (!hdr->somt && !msg->have_somt) + return false; + + /* get length contained in this portion */ + msg->curchunk_idx = 0; + msg->curchunk_len = hdr->msg_len; + msg->curchunk_hdrlen = hdrlen; + + /* we have already gotten an somt - don't bother parsing */ + if (hdr->somt && msg->have_somt) + return false; + + if (hdr->somt) { + memcpy(&msg->initial_hdr, hdr, + sizeof(struct drm_dp_sideband_msg_hdr)); + msg->have_somt = true; + } + if (hdr->eomt) + msg->have_eomt = true; + + return true; +} + +/* this adds a chunk of msg to the builder to get the final msg */ +static bool drm_dp_sideband_append_payload(struct drm_dp_sideband_msg_rx *msg, + u8 *replybuf, u8 replybuflen) +{ + u8 crc4; + + memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen); + msg->curchunk_idx += replybuflen; + + if (msg->curchunk_idx >= msg->curchunk_len) { + /* do CRC */ + crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1); + if (crc4 != msg->chunk[msg->curchunk_len - 1]) + print_hex_dump(KERN_DEBUG, "wrong crc", + DUMP_PREFIX_NONE, 16, 1, + msg->chunk, msg->curchunk_len, false); + /* copy chunk into bigger msg */ + memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1); + msg->curlen += msg->curchunk_len - 1; + } + return true; +} + +static bool drm_dp_sideband_parse_link_address(const struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_sideband_msg_rx *raw, + struct drm_dp_sideband_msg_reply_body *repmsg) +{ + int idx = 1; + int i; + + memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16); + idx += 16; + repmsg->u.link_addr.nports = raw->msg[idx] & 0xf; + idx++; + if (idx > raw->curlen) + goto fail_len; + for (i = 0; i < repmsg->u.link_addr.nports; i++) { + if (raw->msg[idx] & 0x80) + repmsg->u.link_addr.ports[i].input_port = 1; + + repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7; + repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf); + + idx++; + if (idx > raw->curlen) + goto fail_len; + repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1; + repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1; + if (repmsg->u.link_addr.ports[i].input_port == 0) + repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1; + idx++; + if (idx > raw->curlen) + goto fail_len; + if (repmsg->u.link_addr.ports[i].input_port == 0) { + repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]); + idx++; + if (idx > raw->curlen) + goto fail_len; + memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16); + idx += 16; + if (idx > raw->curlen) + goto fail_len; + repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf; + repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf); + idx++; + + } + if (idx > raw->curlen) + goto fail_len; + } + + return true; +fail_len: + DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen); + return false; +} + +static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw, + struct drm_dp_sideband_msg_reply_body *repmsg) +{ + int idx = 1; + + repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf; + idx++; + if (idx > raw->curlen) + goto fail_len; + repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx]; + idx++; + if (idx > raw->curlen) + goto fail_len; + + memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes); + return true; +fail_len: + DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen); + return false; +} + +static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw, + struct drm_dp_sideband_msg_reply_body *repmsg) +{ + int idx = 1; + + repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf; + idx++; + if (idx > raw->curlen) + goto fail_len; + return true; +fail_len: + DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen); + return false; +} + +static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw, + struct drm_dp_sideband_msg_reply_body *repmsg) +{ + int idx = 1; + + repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf); + idx++; + if (idx > raw->curlen) + goto fail_len; + repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx]; + idx++; + /* TODO check */ + memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes); + return true; +fail_len: + DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen); + return false; +} + +static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw, + struct drm_dp_sideband_msg_reply_body *repmsg) +{ + int idx = 1; + + repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf; + repmsg->u.path_resources.fec_capable = raw->msg[idx] & 0x1; + idx++; + if (idx > raw->curlen) + goto fail_len; + repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]); + idx += 2; + if (idx > raw->curlen) + goto fail_len; + repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]); + idx += 2; + if (idx > raw->curlen) + goto fail_len; + return true; +fail_len: + DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen); + return false; +} + +static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw, + struct drm_dp_sideband_msg_reply_body *repmsg) +{ + int idx = 1; + + repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf; + idx++; + if (idx > raw->curlen) + goto fail_len; + repmsg->u.allocate_payload.vcpi = raw->msg[idx]; + idx++; + if (idx > raw->curlen) + goto fail_len; + repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]); + idx += 2; + if (idx > raw->curlen) + goto fail_len; + return true; +fail_len: + DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen); + return false; +} + +static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx *raw, + struct drm_dp_sideband_msg_reply_body *repmsg) +{ + int idx = 1; + + repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf; + idx++; + if (idx > raw->curlen) + goto fail_len; + repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]); + idx += 2; + if (idx > raw->curlen) + goto fail_len; + return true; +fail_len: + DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen); + return false; +} + +static bool drm_dp_sideband_parse_power_updown_phy_ack(struct drm_dp_sideband_msg_rx *raw, + struct drm_dp_sideband_msg_reply_body *repmsg) +{ + int idx = 1; + + repmsg->u.port_number.port_number = (raw->msg[idx] >> 4) & 0xf; + idx++; + if (idx > raw->curlen) { + DRM_DEBUG_KMS("power up/down phy parse length fail %d %d\n", + idx, raw->curlen); + return false; + } + return true; +} + +static bool +drm_dp_sideband_parse_query_stream_enc_status( + struct drm_dp_sideband_msg_rx *raw, + struct drm_dp_sideband_msg_reply_body *repmsg) +{ + struct drm_dp_query_stream_enc_status_ack_reply *reply; + + reply = &repmsg->u.enc_status; + + reply->stream_id = raw->msg[3]; + + reply->reply_signed = raw->msg[2] & BIT(0); + + /* + * NOTE: It's my impression from reading the spec that the below parsing + * is correct. However I noticed while testing with an HDCP 1.4 display + * through an HDCP 2.2 hub that only bit 3 was set. In that case, I + * would expect both bits to be set. So keep the parsing following the + * spec, but beware reality might not match the spec (at least for some + * configurations). + */ + reply->hdcp_1x_device_present = raw->msg[2] & BIT(4); + reply->hdcp_2x_device_present = raw->msg[2] & BIT(3); + + reply->query_capable_device_present = raw->msg[2] & BIT(5); + reply->legacy_device_present = raw->msg[2] & BIT(6); + reply->unauthorizable_device_present = raw->msg[2] & BIT(7); + + reply->auth_completed = !!(raw->msg[1] & BIT(3)); + reply->encryption_enabled = !!(raw->msg[1] & BIT(4)); + reply->repeater_present = !!(raw->msg[1] & BIT(5)); + reply->state = (raw->msg[1] & GENMASK(7, 6)) >> 6; + + return true; +} + +static bool drm_dp_sideband_parse_reply(const struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_sideband_msg_rx *raw, + struct drm_dp_sideband_msg_reply_body *msg) +{ + memset(msg, 0, sizeof(*msg)); + msg->reply_type = (raw->msg[0] & 0x80) >> 7; + msg->req_type = (raw->msg[0] & 0x7f); + + if (msg->reply_type == DP_SIDEBAND_REPLY_NAK) { + memcpy(msg->u.nak.guid, &raw->msg[1], 16); + msg->u.nak.reason = raw->msg[17]; + msg->u.nak.nak_data = raw->msg[18]; + return false; + } + + switch (msg->req_type) { + case DP_LINK_ADDRESS: + return drm_dp_sideband_parse_link_address(mgr, raw, msg); + case DP_QUERY_PAYLOAD: + return drm_dp_sideband_parse_query_payload_ack(raw, msg); + case DP_REMOTE_DPCD_READ: + return drm_dp_sideband_parse_remote_dpcd_read(raw, msg); + case DP_REMOTE_DPCD_WRITE: + return drm_dp_sideband_parse_remote_dpcd_write(raw, msg); + case DP_REMOTE_I2C_READ: + return drm_dp_sideband_parse_remote_i2c_read_ack(raw, msg); + case DP_REMOTE_I2C_WRITE: + return true; /* since there's nothing to parse */ + case DP_ENUM_PATH_RESOURCES: + return drm_dp_sideband_parse_enum_path_resources_ack(raw, msg); + case DP_ALLOCATE_PAYLOAD: + return drm_dp_sideband_parse_allocate_payload_ack(raw, msg); + case DP_POWER_DOWN_PHY: + case DP_POWER_UP_PHY: + return drm_dp_sideband_parse_power_updown_phy_ack(raw, msg); + case DP_CLEAR_PAYLOAD_ID_TABLE: + return true; /* since there's nothing to parse */ + case DP_QUERY_STREAM_ENC_STATUS: + return drm_dp_sideband_parse_query_stream_enc_status(raw, msg); + default: + drm_err(mgr->dev, "Got unknown reply 0x%02x (%s)\n", + msg->req_type, drm_dp_mst_req_type_str(msg->req_type)); + return false; + } +} + +static bool +drm_dp_sideband_parse_connection_status_notify(const struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_sideband_msg_rx *raw, + struct drm_dp_sideband_msg_req_body *msg) +{ + int idx = 1; + + msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4; + idx++; + if (idx > raw->curlen) + goto fail_len; + + memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16); + idx += 16; + if (idx > raw->curlen) + goto fail_len; + + msg->u.conn_stat.legacy_device_plug_status = (raw->msg[idx] >> 6) & 0x1; + msg->u.conn_stat.displayport_device_plug_status = (raw->msg[idx] >> 5) & 0x1; + msg->u.conn_stat.message_capability_status = (raw->msg[idx] >> 4) & 0x1; + msg->u.conn_stat.input_port = (raw->msg[idx] >> 3) & 0x1; + msg->u.conn_stat.peer_device_type = (raw->msg[idx] & 0x7); + idx++; + return true; +fail_len: + drm_dbg_kms(mgr->dev, "connection status reply parse length fail %d %d\n", + idx, raw->curlen); + return false; +} + +static bool drm_dp_sideband_parse_resource_status_notify(const struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_sideband_msg_rx *raw, + struct drm_dp_sideband_msg_req_body *msg) +{ + int idx = 1; + + msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4; + idx++; + if (idx > raw->curlen) + goto fail_len; + + memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16); + idx += 16; + if (idx > raw->curlen) + goto fail_len; + + msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]); + idx++; + return true; +fail_len: + drm_dbg_kms(mgr->dev, "resource status reply parse length fail %d %d\n", idx, raw->curlen); + return false; +} + +static bool drm_dp_sideband_parse_req(const struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_sideband_msg_rx *raw, + struct drm_dp_sideband_msg_req_body *msg) +{ + memset(msg, 0, sizeof(*msg)); + msg->req_type = (raw->msg[0] & 0x7f); + + switch (msg->req_type) { + case DP_CONNECTION_STATUS_NOTIFY: + return drm_dp_sideband_parse_connection_status_notify(mgr, raw, msg); + case DP_RESOURCE_STATUS_NOTIFY: + return drm_dp_sideband_parse_resource_status_notify(mgr, raw, msg); + default: + drm_err(mgr->dev, "Got unknown request 0x%02x (%s)\n", + msg->req_type, drm_dp_mst_req_type_str(msg->req_type)); + return false; + } +} + +static void build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, + u8 port_num, u32 offset, u8 num_bytes, u8 *bytes) +{ + struct drm_dp_sideband_msg_req_body req; + + req.req_type = DP_REMOTE_DPCD_WRITE; + req.u.dpcd_write.port_number = port_num; + req.u.dpcd_write.dpcd_address = offset; + req.u.dpcd_write.num_bytes = num_bytes; + req.u.dpcd_write.bytes = bytes; + drm_dp_encode_sideband_req(&req, msg); +} + +static void build_link_address(struct drm_dp_sideband_msg_tx *msg) +{ + struct drm_dp_sideband_msg_req_body req; + + req.req_type = DP_LINK_ADDRESS; + drm_dp_encode_sideband_req(&req, msg); +} + +static void build_clear_payload_id_table(struct drm_dp_sideband_msg_tx *msg) +{ + struct drm_dp_sideband_msg_req_body req; + + req.req_type = DP_CLEAR_PAYLOAD_ID_TABLE; + drm_dp_encode_sideband_req(&req, msg); + msg->path_msg = true; +} + +static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, + int port_num) +{ + struct drm_dp_sideband_msg_req_body req; + + req.req_type = DP_ENUM_PATH_RESOURCES; + req.u.port_num.port_number = port_num; + drm_dp_encode_sideband_req(&req, msg); + msg->path_msg = true; + return 0; +} + +static void build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, + int port_num, + u8 vcpi, uint16_t pbn, + u8 number_sdp_streams, + u8 *sdp_stream_sink) +{ + struct drm_dp_sideband_msg_req_body req; + + memset(&req, 0, sizeof(req)); + req.req_type = DP_ALLOCATE_PAYLOAD; + req.u.allocate_payload.port_number = port_num; + req.u.allocate_payload.vcpi = vcpi; + req.u.allocate_payload.pbn = pbn; + req.u.allocate_payload.number_sdp_streams = number_sdp_streams; + memcpy(req.u.allocate_payload.sdp_stream_sink, sdp_stream_sink, + number_sdp_streams); + drm_dp_encode_sideband_req(&req, msg); + msg->path_msg = true; +} + +static void build_power_updown_phy(struct drm_dp_sideband_msg_tx *msg, + int port_num, bool power_up) +{ + struct drm_dp_sideband_msg_req_body req; + + if (power_up) + req.req_type = DP_POWER_UP_PHY; + else + req.req_type = DP_POWER_DOWN_PHY; + + req.u.port_num.port_number = port_num; + drm_dp_encode_sideband_req(&req, msg); + msg->path_msg = true; +} + +static int +build_query_stream_enc_status(struct drm_dp_sideband_msg_tx *msg, u8 stream_id, + u8 *q_id) +{ + struct drm_dp_sideband_msg_req_body req; + + req.req_type = DP_QUERY_STREAM_ENC_STATUS; + req.u.enc_status.stream_id = stream_id; + memcpy(req.u.enc_status.client_id, q_id, + sizeof(req.u.enc_status.client_id)); + req.u.enc_status.stream_event = 0; + req.u.enc_status.valid_stream_event = false; + req.u.enc_status.stream_behavior = 0; + req.u.enc_status.valid_stream_behavior = false; + + drm_dp_encode_sideband_req(&req, msg); + return 0; +} + +static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_sideband_msg_tx *txmsg) +{ + unsigned int state; + + /* + * All updates to txmsg->state are protected by mgr->qlock, and the two + * cases we check here are terminal states. For those the barriers + * provided by the wake_up/wait_event pair are enough. + */ + state = READ_ONCE(txmsg->state); + return (state == DRM_DP_SIDEBAND_TX_RX || + state == DRM_DP_SIDEBAND_TX_TIMEOUT); +} + +static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb, + struct drm_dp_sideband_msg_tx *txmsg) +{ + struct drm_dp_mst_topology_mgr *mgr = mstb->mgr; + unsigned long wait_timeout = msecs_to_jiffies(4000); + unsigned long wait_expires = jiffies + wait_timeout; + int ret; + + for (;;) { + /* + * If the driver provides a way for this, change to + * poll-waiting for the MST reply interrupt if we didn't receive + * it for 50 msec. This would cater for cases where the HPD + * pulse signal got lost somewhere, even though the sink raised + * the corresponding MST interrupt correctly. One example is the + * Club 3D CAC-1557 TypeC -> DP adapter which for some reason + * filters out short pulses with a duration less than ~540 usec. + * + * The poll period is 50 msec to avoid missing an interrupt + * after the sink has cleared it (after a 110msec timeout + * since it raised the interrupt). + */ + ret = wait_event_timeout(mgr->tx_waitq, + check_txmsg_state(mgr, txmsg), + mgr->cbs->poll_hpd_irq ? + msecs_to_jiffies(50) : + wait_timeout); + + if (ret || !mgr->cbs->poll_hpd_irq || + time_after(jiffies, wait_expires)) + break; + + mgr->cbs->poll_hpd_irq(mgr); + } + + mutex_lock(&mgr->qlock); + if (ret > 0) { + if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) { + ret = -EIO; + goto out; + } + } else { + drm_dbg_kms(mgr->dev, "timedout msg send %p %d %d\n", + txmsg, txmsg->state, txmsg->seqno); + + /* dump some state */ + ret = -EIO; + + /* remove from q */ + if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED || + txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND || + txmsg->state == DRM_DP_SIDEBAND_TX_SENT) + list_del(&txmsg->next); + } +out: + if (unlikely(ret == -EIO) && drm_debug_enabled(DRM_UT_DP)) { + struct drm_printer p = drm_debug_printer(DBG_PREFIX); + + drm_dp_mst_dump_sideband_msg_tx(&p, txmsg); + } + mutex_unlock(&mgr->qlock); + + drm_dp_mst_kick_tx(mgr); + return ret; +} + +static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad) +{ + struct drm_dp_mst_branch *mstb; + + mstb = kzalloc(sizeof(*mstb), GFP_KERNEL); + if (!mstb) + return NULL; + + mstb->lct = lct; + if (lct > 1) + memcpy(mstb->rad, rad, lct / 2); + INIT_LIST_HEAD(&mstb->ports); + kref_init(&mstb->topology_kref); + kref_init(&mstb->malloc_kref); + return mstb; +} + +static void drm_dp_free_mst_branch_device(struct kref *kref) +{ + struct drm_dp_mst_branch *mstb = + container_of(kref, struct drm_dp_mst_branch, malloc_kref); + + if (mstb->port_parent) + drm_dp_mst_put_port_malloc(mstb->port_parent); + + kfree(mstb); +} + +/** + * DOC: Branch device and port refcounting + * + * Topology refcount overview + * ~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * The refcounting schemes for &struct drm_dp_mst_branch and &struct + * drm_dp_mst_port are somewhat unusual. Both ports and branch devices have + * two different kinds of refcounts: topology refcounts, and malloc refcounts. + * + * Topology refcounts are not exposed to drivers, and are handled internally + * by the DP MST helpers. The helpers use them in order to prevent the + * in-memory topology state from being changed in the middle of critical + * operations like changing the internal state of payload allocations. This + * means each branch and port will be considered to be connected to the rest + * of the topology until its topology refcount reaches zero. Additionally, + * for ports this means that their associated &struct drm_connector will stay + * registered with userspace until the port's refcount reaches 0. + * + * Malloc refcount overview + * ~~~~~~~~~~~~~~~~~~~~~~~~ + * + * Malloc references are used to keep a &struct drm_dp_mst_port or &struct + * drm_dp_mst_branch allocated even after all of its topology references have + * been dropped, so that the driver or MST helpers can safely access each + * branch's last known state before it was disconnected from the topology. + * When the malloc refcount of a port or branch reaches 0, the memory + * allocation containing the &struct drm_dp_mst_branch or &struct + * drm_dp_mst_port respectively will be freed. + * + * For &struct drm_dp_mst_branch, malloc refcounts are not currently exposed + * to drivers. As of writing this documentation, there are no drivers that + * have a usecase for accessing &struct drm_dp_mst_branch outside of the MST + * helpers. Exposing this API to drivers in a race-free manner would take more + * tweaking of the refcounting scheme, however patches are welcome provided + * there is a legitimate driver usecase for this. + * + * Refcount relationships in a topology + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * Let's take a look at why the relationship between topology and malloc + * refcounts is designed the way it is. + * + * .. kernel-figure:: dp-mst/topology-figure-1.dot + * + * An example of topology and malloc refs in a DP MST topology with two + * active payloads. Topology refcount increments are indicated by solid + * lines, and malloc refcount increments are indicated by dashed lines. + * Each starts from the branch which incremented the refcount, and ends at + * the branch to which the refcount belongs to, i.e. the arrow points the + * same way as the C pointers used to reference a structure. + * + * As you can see in the above figure, every branch increments the topology + * refcount of its children, and increments the malloc refcount of its + * parent. Additionally, every payload increments the malloc refcount of its + * assigned port by 1. + * + * So, what would happen if MSTB #3 from the above figure was unplugged from + * the system, but the driver hadn't yet removed payload #2 from port #3? The + * topology would start to look like the figure below. + * + * .. kernel-figure:: dp-mst/topology-figure-2.dot + * + * Ports and branch devices which have been released from memory are + * colored grey, and references which have been removed are colored red. + * + * Whenever a port or branch device's topology refcount reaches zero, it will + * decrement the topology refcounts of all its children, the malloc refcount + * of its parent, and finally its own malloc refcount. For MSTB #4 and port + * #4, this means they both have been disconnected from the topology and freed + * from memory. But, because payload #2 is still holding a reference to port + * #3, port #3 is removed from the topology but its &struct drm_dp_mst_port + * is still accessible from memory. This also means port #3 has not yet + * decremented the malloc refcount of MSTB #3, so its &struct + * drm_dp_mst_branch will also stay allocated in memory until port #3's + * malloc refcount reaches 0. + * + * This relationship is necessary because in order to release payload #2, we + * need to be able to figure out the last relative of port #3 that's still + * connected to the topology. In this case, we would travel up the topology as + * shown below. + * + * .. kernel-figure:: dp-mst/topology-figure-3.dot + * + * And finally, remove payload #2 by communicating with port #2 through + * sideband transactions. + */ + +/** + * drm_dp_mst_get_mstb_malloc() - Increment the malloc refcount of a branch + * device + * @mstb: The &struct drm_dp_mst_branch to increment the malloc refcount of + * + * Increments &drm_dp_mst_branch.malloc_kref. When + * &drm_dp_mst_branch.malloc_kref reaches 0, the memory allocation for @mstb + * will be released and @mstb may no longer be used. + * + * See also: drm_dp_mst_put_mstb_malloc() + */ +static void +drm_dp_mst_get_mstb_malloc(struct drm_dp_mst_branch *mstb) +{ + kref_get(&mstb->malloc_kref); + drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->malloc_kref)); +} + +/** + * drm_dp_mst_put_mstb_malloc() - Decrement the malloc refcount of a branch + * device + * @mstb: The &struct drm_dp_mst_branch to decrement the malloc refcount of + * + * Decrements &drm_dp_mst_branch.malloc_kref. When + * &drm_dp_mst_branch.malloc_kref reaches 0, the memory allocation for @mstb + * will be released and @mstb may no longer be used. + * + * See also: drm_dp_mst_get_mstb_malloc() + */ +static void +drm_dp_mst_put_mstb_malloc(struct drm_dp_mst_branch *mstb) +{ + drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->malloc_kref) - 1); + kref_put(&mstb->malloc_kref, drm_dp_free_mst_branch_device); +} + +static void drm_dp_free_mst_port(struct kref *kref) +{ + struct drm_dp_mst_port *port = + container_of(kref, struct drm_dp_mst_port, malloc_kref); + + drm_dp_mst_put_mstb_malloc(port->parent); + kfree(port); +} + +/** + * drm_dp_mst_get_port_malloc() - Increment the malloc refcount of an MST port + * @port: The &struct drm_dp_mst_port to increment the malloc refcount of + * + * Increments &drm_dp_mst_port.malloc_kref. When &drm_dp_mst_port.malloc_kref + * reaches 0, the memory allocation for @port will be released and @port may + * no longer be used. + * + * Because @port could potentially be freed at any time by the DP MST helpers + * if &drm_dp_mst_port.malloc_kref reaches 0, including during a call to this + * function, drivers that which to make use of &struct drm_dp_mst_port should + * ensure that they grab at least one main malloc reference to their MST ports + * in &drm_dp_mst_topology_cbs.add_connector. This callback is called before + * there is any chance for &drm_dp_mst_port.malloc_kref to reach 0. + * + * See also: drm_dp_mst_put_port_malloc() + */ +void +drm_dp_mst_get_port_malloc(struct drm_dp_mst_port *port) +{ + kref_get(&port->malloc_kref); + drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->malloc_kref)); +} +EXPORT_SYMBOL(drm_dp_mst_get_port_malloc); + +/** + * drm_dp_mst_put_port_malloc() - Decrement the malloc refcount of an MST port + * @port: The &struct drm_dp_mst_port to decrement the malloc refcount of + * + * Decrements &drm_dp_mst_port.malloc_kref. When &drm_dp_mst_port.malloc_kref + * reaches 0, the memory allocation for @port will be released and @port may + * no longer be used. + * + * See also: drm_dp_mst_get_port_malloc() + */ +void +drm_dp_mst_put_port_malloc(struct drm_dp_mst_port *port) +{ + drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->malloc_kref) - 1); + kref_put(&port->malloc_kref, drm_dp_free_mst_port); +} +EXPORT_SYMBOL(drm_dp_mst_put_port_malloc); + +#if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS) + +#define STACK_DEPTH 8 + +static noinline void +__topology_ref_save(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_topology_ref_history *history, + enum drm_dp_mst_topology_ref_type type) +{ + struct drm_dp_mst_topology_ref_entry *entry = NULL; + depot_stack_handle_t backtrace; + ulong stack_entries[STACK_DEPTH]; + uint n; + int i; + + n = stack_trace_save(stack_entries, ARRAY_SIZE(stack_entries), 1); + backtrace = stack_depot_save(stack_entries, n, GFP_KERNEL); + if (!backtrace) + return; + + /* Try to find an existing entry for this backtrace */ + for (i = 0; i < history->len; i++) { + if (history->entries[i].backtrace == backtrace) { + entry = &history->entries[i]; + break; + } + } + + /* Otherwise add one */ + if (!entry) { + struct drm_dp_mst_topology_ref_entry *new; + int new_len = history->len + 1; + + new = krealloc(history->entries, sizeof(*new) * new_len, + GFP_KERNEL); + if (!new) + return; + + entry = &new[history->len]; + history->len = new_len; + history->entries = new; + + entry->backtrace = backtrace; + entry->type = type; + entry->count = 0; + } + entry->count++; + entry->ts_nsec = ktime_get_ns(); +} + +static int +topology_ref_history_cmp(const void *a, const void *b) +{ + const struct drm_dp_mst_topology_ref_entry *entry_a = a, *entry_b = b; + + if (entry_a->ts_nsec > entry_b->ts_nsec) + return 1; + else if (entry_a->ts_nsec < entry_b->ts_nsec) + return -1; + else + return 0; +} + +static inline const char * +topology_ref_type_to_str(enum drm_dp_mst_topology_ref_type type) +{ + if (type == DRM_DP_MST_TOPOLOGY_REF_GET) + return "get"; + else + return "put"; +} + +static void +__dump_topology_ref_history(struct drm_dp_mst_topology_ref_history *history, + void *ptr, const char *type_str) +{ + struct drm_printer p = drm_debug_printer(DBG_PREFIX); + char *buf = kzalloc(PAGE_SIZE, GFP_KERNEL); + int i; + + if (!buf) + return; + + if (!history->len) + goto out; + + /* First, sort the list so that it goes from oldest to newest + * reference entry + */ + sort(history->entries, history->len, sizeof(*history->entries), + topology_ref_history_cmp, NULL); + + drm_printf(&p, "%s (%p) topology count reached 0, dumping history:\n", + type_str, ptr); + + for (i = 0; i < history->len; i++) { + const struct drm_dp_mst_topology_ref_entry *entry = + &history->entries[i]; + u64 ts_nsec = entry->ts_nsec; + u32 rem_nsec = do_div(ts_nsec, 1000000000); + + stack_depot_snprint(entry->backtrace, buf, PAGE_SIZE, 4); + + drm_printf(&p, " %d %ss (last at %5llu.%06u):\n%s", + entry->count, + topology_ref_type_to_str(entry->type), + ts_nsec, rem_nsec / 1000, buf); + } + + /* Now free the history, since this is the only time we expose it */ + kfree(history->entries); +out: + kfree(buf); +} + +static __always_inline void +drm_dp_mst_dump_mstb_topology_history(struct drm_dp_mst_branch *mstb) +{ + __dump_topology_ref_history(&mstb->topology_ref_history, mstb, + "MSTB"); +} + +static __always_inline void +drm_dp_mst_dump_port_topology_history(struct drm_dp_mst_port *port) +{ + __dump_topology_ref_history(&port->topology_ref_history, port, + "Port"); +} + +static __always_inline void +save_mstb_topology_ref(struct drm_dp_mst_branch *mstb, + enum drm_dp_mst_topology_ref_type type) +{ + __topology_ref_save(mstb->mgr, &mstb->topology_ref_history, type); +} + +static __always_inline void +save_port_topology_ref(struct drm_dp_mst_port *port, + enum drm_dp_mst_topology_ref_type type) +{ + __topology_ref_save(port->mgr, &port->topology_ref_history, type); +} + +static inline void +topology_ref_history_lock(struct drm_dp_mst_topology_mgr *mgr) +{ + mutex_lock(&mgr->topology_ref_history_lock); +} + +static inline void +topology_ref_history_unlock(struct drm_dp_mst_topology_mgr *mgr) +{ + mutex_unlock(&mgr->topology_ref_history_lock); +} +#else +static inline void +topology_ref_history_lock(struct drm_dp_mst_topology_mgr *mgr) {} +static inline void +topology_ref_history_unlock(struct drm_dp_mst_topology_mgr *mgr) {} +static inline void +drm_dp_mst_dump_mstb_topology_history(struct drm_dp_mst_branch *mstb) {} +static inline void +drm_dp_mst_dump_port_topology_history(struct drm_dp_mst_port *port) {} +#define save_mstb_topology_ref(mstb, type) +#define save_port_topology_ref(port, type) +#endif + +struct drm_dp_mst_atomic_payload * +drm_atomic_get_mst_payload_state(struct drm_dp_mst_topology_state *state, + struct drm_dp_mst_port *port) +{ + struct drm_dp_mst_atomic_payload *payload; + + list_for_each_entry(payload, &state->payloads, next) + if (payload->port == port) + return payload; + + return NULL; +} +EXPORT_SYMBOL(drm_atomic_get_mst_payload_state); + +static void drm_dp_destroy_mst_branch_device(struct kref *kref) +{ + struct drm_dp_mst_branch *mstb = + container_of(kref, struct drm_dp_mst_branch, topology_kref); + struct drm_dp_mst_topology_mgr *mgr = mstb->mgr; + + drm_dp_mst_dump_mstb_topology_history(mstb); + + INIT_LIST_HEAD(&mstb->destroy_next); + + /* + * This can get called under mgr->mutex, so we need to perform the + * actual destruction of the mstb in another worker + */ + mutex_lock(&mgr->delayed_destroy_lock); + list_add(&mstb->destroy_next, &mgr->destroy_branch_device_list); + mutex_unlock(&mgr->delayed_destroy_lock); + queue_work(mgr->delayed_destroy_wq, &mgr->delayed_destroy_work); +} + +/** + * drm_dp_mst_topology_try_get_mstb() - Increment the topology refcount of a + * branch device unless it's zero + * @mstb: &struct drm_dp_mst_branch to increment the topology refcount of + * + * Attempts to grab a topology reference to @mstb, if it hasn't yet been + * removed from the topology (e.g. &drm_dp_mst_branch.topology_kref has + * reached 0). Holding a topology reference implies that a malloc reference + * will be held to @mstb as long as the user holds the topology reference. + * + * Care should be taken to ensure that the user has at least one malloc + * reference to @mstb. If you already have a topology reference to @mstb, you + * should use drm_dp_mst_topology_get_mstb() instead. + * + * See also: + * drm_dp_mst_topology_get_mstb() + * drm_dp_mst_topology_put_mstb() + * + * Returns: + * * 1: A topology reference was grabbed successfully + * * 0: @port is no longer in the topology, no reference was grabbed + */ +static int __must_check +drm_dp_mst_topology_try_get_mstb(struct drm_dp_mst_branch *mstb) +{ + int ret; + + topology_ref_history_lock(mstb->mgr); + ret = kref_get_unless_zero(&mstb->topology_kref); + if (ret) { + drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->topology_kref)); + save_mstb_topology_ref(mstb, DRM_DP_MST_TOPOLOGY_REF_GET); + } + + topology_ref_history_unlock(mstb->mgr); + + return ret; +} + +/** + * drm_dp_mst_topology_get_mstb() - Increment the topology refcount of a + * branch device + * @mstb: The &struct drm_dp_mst_branch to increment the topology refcount of + * + * Increments &drm_dp_mst_branch.topology_refcount without checking whether or + * not it's already reached 0. This is only valid to use in scenarios where + * you are already guaranteed to have at least one active topology reference + * to @mstb. Otherwise, drm_dp_mst_topology_try_get_mstb() must be used. + * + * See also: + * drm_dp_mst_topology_try_get_mstb() + * drm_dp_mst_topology_put_mstb() + */ +static void drm_dp_mst_topology_get_mstb(struct drm_dp_mst_branch *mstb) +{ + topology_ref_history_lock(mstb->mgr); + + save_mstb_topology_ref(mstb, DRM_DP_MST_TOPOLOGY_REF_GET); + WARN_ON(kref_read(&mstb->topology_kref) == 0); + kref_get(&mstb->topology_kref); + drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->topology_kref)); + + topology_ref_history_unlock(mstb->mgr); +} + +/** + * drm_dp_mst_topology_put_mstb() - release a topology reference to a branch + * device + * @mstb: The &struct drm_dp_mst_branch to release the topology reference from + * + * Releases a topology reference from @mstb by decrementing + * &drm_dp_mst_branch.topology_kref. + * + * See also: + * drm_dp_mst_topology_try_get_mstb() + * drm_dp_mst_topology_get_mstb() + */ +static void +drm_dp_mst_topology_put_mstb(struct drm_dp_mst_branch *mstb) +{ + topology_ref_history_lock(mstb->mgr); + + drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->topology_kref) - 1); + save_mstb_topology_ref(mstb, DRM_DP_MST_TOPOLOGY_REF_PUT); + + topology_ref_history_unlock(mstb->mgr); + kref_put(&mstb->topology_kref, drm_dp_destroy_mst_branch_device); +} + +static void drm_dp_destroy_port(struct kref *kref) +{ + struct drm_dp_mst_port *port = + container_of(kref, struct drm_dp_mst_port, topology_kref); + struct drm_dp_mst_topology_mgr *mgr = port->mgr; + + drm_dp_mst_dump_port_topology_history(port); + + /* There's nothing that needs locking to destroy an input port yet */ + if (port->input) { + drm_dp_mst_put_port_malloc(port); + return; + } + + kfree(port->cached_edid); + + /* + * we can't destroy the connector here, as we might be holding the + * mode_config.mutex from an EDID retrieval + */ + mutex_lock(&mgr->delayed_destroy_lock); + list_add(&port->next, &mgr->destroy_port_list); + mutex_unlock(&mgr->delayed_destroy_lock); + queue_work(mgr->delayed_destroy_wq, &mgr->delayed_destroy_work); +} + +/** + * drm_dp_mst_topology_try_get_port() - Increment the topology refcount of a + * port unless it's zero + * @port: &struct drm_dp_mst_port to increment the topology refcount of + * + * Attempts to grab a topology reference to @port, if it hasn't yet been + * removed from the topology (e.g. &drm_dp_mst_port.topology_kref has reached + * 0). Holding a topology reference implies that a malloc reference will be + * held to @port as long as the user holds the topology reference. + * + * Care should be taken to ensure that the user has at least one malloc + * reference to @port. If you already have a topology reference to @port, you + * should use drm_dp_mst_topology_get_port() instead. + * + * See also: + * drm_dp_mst_topology_get_port() + * drm_dp_mst_topology_put_port() + * + * Returns: + * * 1: A topology reference was grabbed successfully + * * 0: @port is no longer in the topology, no reference was grabbed + */ +static int __must_check +drm_dp_mst_topology_try_get_port(struct drm_dp_mst_port *port) +{ + int ret; + + topology_ref_history_lock(port->mgr); + ret = kref_get_unless_zero(&port->topology_kref); + if (ret) { + drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->topology_kref)); + save_port_topology_ref(port, DRM_DP_MST_TOPOLOGY_REF_GET); + } + + topology_ref_history_unlock(port->mgr); + return ret; +} + +/** + * drm_dp_mst_topology_get_port() - Increment the topology refcount of a port + * @port: The &struct drm_dp_mst_port to increment the topology refcount of + * + * Increments &drm_dp_mst_port.topology_refcount without checking whether or + * not it's already reached 0. This is only valid to use in scenarios where + * you are already guaranteed to have at least one active topology reference + * to @port. Otherwise, drm_dp_mst_topology_try_get_port() must be used. + * + * See also: + * drm_dp_mst_topology_try_get_port() + * drm_dp_mst_topology_put_port() + */ +static void drm_dp_mst_topology_get_port(struct drm_dp_mst_port *port) +{ + topology_ref_history_lock(port->mgr); + + WARN_ON(kref_read(&port->topology_kref) == 0); + kref_get(&port->topology_kref); + drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->topology_kref)); + save_port_topology_ref(port, DRM_DP_MST_TOPOLOGY_REF_GET); + + topology_ref_history_unlock(port->mgr); +} + +/** + * drm_dp_mst_topology_put_port() - release a topology reference to a port + * @port: The &struct drm_dp_mst_port to release the topology reference from + * + * Releases a topology reference from @port by decrementing + * &drm_dp_mst_port.topology_kref. + * + * See also: + * drm_dp_mst_topology_try_get_port() + * drm_dp_mst_topology_get_port() + */ +static void drm_dp_mst_topology_put_port(struct drm_dp_mst_port *port) +{ + topology_ref_history_lock(port->mgr); + + drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->topology_kref) - 1); + save_port_topology_ref(port, DRM_DP_MST_TOPOLOGY_REF_PUT); + + topology_ref_history_unlock(port->mgr); + kref_put(&port->topology_kref, drm_dp_destroy_port); +} + +static struct drm_dp_mst_branch * +drm_dp_mst_topology_get_mstb_validated_locked(struct drm_dp_mst_branch *mstb, + struct drm_dp_mst_branch *to_find) +{ + struct drm_dp_mst_port *port; + struct drm_dp_mst_branch *rmstb; + + if (to_find == mstb) + return mstb; + + list_for_each_entry(port, &mstb->ports, next) { + if (port->mstb) { + rmstb = drm_dp_mst_topology_get_mstb_validated_locked( + port->mstb, to_find); + if (rmstb) + return rmstb; + } + } + return NULL; +} + +static struct drm_dp_mst_branch * +drm_dp_mst_topology_get_mstb_validated(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_branch *mstb) +{ + struct drm_dp_mst_branch *rmstb = NULL; + + mutex_lock(&mgr->lock); + if (mgr->mst_primary) { + rmstb = drm_dp_mst_topology_get_mstb_validated_locked( + mgr->mst_primary, mstb); + + if (rmstb && !drm_dp_mst_topology_try_get_mstb(rmstb)) + rmstb = NULL; + } + mutex_unlock(&mgr->lock); + return rmstb; +} + +static struct drm_dp_mst_port * +drm_dp_mst_topology_get_port_validated_locked(struct drm_dp_mst_branch *mstb, + struct drm_dp_mst_port *to_find) +{ + struct drm_dp_mst_port *port, *mport; + + list_for_each_entry(port, &mstb->ports, next) { + if (port == to_find) + return port; + + if (port->mstb) { + mport = drm_dp_mst_topology_get_port_validated_locked( + port->mstb, to_find); + if (mport) + return mport; + } + } + return NULL; +} + +static struct drm_dp_mst_port * +drm_dp_mst_topology_get_port_validated(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port) +{ + struct drm_dp_mst_port *rport = NULL; + + mutex_lock(&mgr->lock); + if (mgr->mst_primary) { + rport = drm_dp_mst_topology_get_port_validated_locked( + mgr->mst_primary, port); + + if (rport && !drm_dp_mst_topology_try_get_port(rport)) + rport = NULL; + } + mutex_unlock(&mgr->lock); + return rport; +} + +static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num) +{ + struct drm_dp_mst_port *port; + int ret; + + list_for_each_entry(port, &mstb->ports, next) { + if (port->port_num == port_num) { + ret = drm_dp_mst_topology_try_get_port(port); + return ret ? port : NULL; + } + } + + return NULL; +} + +/* + * calculate a new RAD for this MST branch device + * if parent has an LCT of 2 then it has 1 nibble of RAD, + * if parent has an LCT of 3 then it has 2 nibbles of RAD, + */ +static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port, + u8 *rad) +{ + int parent_lct = port->parent->lct; + int shift = 4; + int idx = (parent_lct - 1) / 2; + + if (parent_lct > 1) { + memcpy(rad, port->parent->rad, idx + 1); + shift = (parent_lct % 2) ? 4 : 0; + } else + rad[0] = 0; + + rad[idx] |= port->port_num << shift; + return parent_lct + 1; +} + +static bool drm_dp_mst_is_end_device(u8 pdt, bool mcs) +{ + switch (pdt) { + case DP_PEER_DEVICE_DP_LEGACY_CONV: + case DP_PEER_DEVICE_SST_SINK: + return true; + case DP_PEER_DEVICE_MST_BRANCHING: + /* For sst branch device */ + if (!mcs) + return true; + + return false; + } + return true; +} + +static int +drm_dp_port_set_pdt(struct drm_dp_mst_port *port, u8 new_pdt, + bool new_mcs) +{ + struct drm_dp_mst_topology_mgr *mgr = port->mgr; + struct drm_dp_mst_branch *mstb; + u8 rad[8], lct; + int ret = 0; + + if (port->pdt == new_pdt && port->mcs == new_mcs) + return 0; + + /* Teardown the old pdt, if there is one */ + if (port->pdt != DP_PEER_DEVICE_NONE) { + if (drm_dp_mst_is_end_device(port->pdt, port->mcs)) { + /* + * If the new PDT would also have an i2c bus, + * don't bother with reregistering it + */ + if (new_pdt != DP_PEER_DEVICE_NONE && + drm_dp_mst_is_end_device(new_pdt, new_mcs)) { + port->pdt = new_pdt; + port->mcs = new_mcs; + return 0; + } + + /* remove i2c over sideband */ + drm_dp_mst_unregister_i2c_bus(port); + } else { + mutex_lock(&mgr->lock); + drm_dp_mst_topology_put_mstb(port->mstb); + port->mstb = NULL; + mutex_unlock(&mgr->lock); + } + } + + port->pdt = new_pdt; + port->mcs = new_mcs; + + if (port->pdt != DP_PEER_DEVICE_NONE) { + if (drm_dp_mst_is_end_device(port->pdt, port->mcs)) { + /* add i2c over sideband */ + ret = drm_dp_mst_register_i2c_bus(port); + } else { + lct = drm_dp_calculate_rad(port, rad); + mstb = drm_dp_add_mst_branch_device(lct, rad); + if (!mstb) { + ret = -ENOMEM; + drm_err(mgr->dev, "Failed to create MSTB for port %p", port); + goto out; + } + + mutex_lock(&mgr->lock); + port->mstb = mstb; + mstb->mgr = port->mgr; + mstb->port_parent = port; + + /* + * Make sure this port's memory allocation stays + * around until its child MSTB releases it + */ + drm_dp_mst_get_port_malloc(port); + mutex_unlock(&mgr->lock); + + /* And make sure we send a link address for this */ + ret = 1; + } + } + +out: + if (ret < 0) + port->pdt = DP_PEER_DEVICE_NONE; + return ret; +} + +/** + * drm_dp_mst_dpcd_read() - read a series of bytes from the DPCD via sideband + * @aux: Fake sideband AUX CH + * @offset: address of the (first) register to read + * @buffer: buffer to store the register values + * @size: number of bytes in @buffer + * + * Performs the same functionality for remote devices via + * sideband messaging as drm_dp_dpcd_read() does for local + * devices via actual AUX CH. + * + * Return: Number of bytes read, or negative error code on failure. + */ +ssize_t drm_dp_mst_dpcd_read(struct drm_dp_aux *aux, + unsigned int offset, void *buffer, size_t size) +{ + struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, + aux); + + return drm_dp_send_dpcd_read(port->mgr, port, + offset, size, buffer); +} + +/** + * drm_dp_mst_dpcd_write() - write a series of bytes to the DPCD via sideband + * @aux: Fake sideband AUX CH + * @offset: address of the (first) register to write + * @buffer: buffer containing the values to write + * @size: number of bytes in @buffer + * + * Performs the same functionality for remote devices via + * sideband messaging as drm_dp_dpcd_write() does for local + * devices via actual AUX CH. + * + * Return: number of bytes written on success, negative error code on failure. + */ +ssize_t drm_dp_mst_dpcd_write(struct drm_dp_aux *aux, + unsigned int offset, void *buffer, size_t size) +{ + struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, + aux); + + return drm_dp_send_dpcd_write(port->mgr, port, + offset, size, buffer); +} + +static int drm_dp_check_mstb_guid(struct drm_dp_mst_branch *mstb, u8 *guid) +{ + int ret = 0; + + memcpy(mstb->guid, guid, 16); + + if (!drm_dp_validate_guid(mstb->mgr, mstb->guid)) { + if (mstb->port_parent) { + ret = drm_dp_send_dpcd_write(mstb->mgr, + mstb->port_parent, + DP_GUID, 16, mstb->guid); + } else { + ret = drm_dp_dpcd_write(mstb->mgr->aux, + DP_GUID, mstb->guid, 16); + } + } + + if (ret < 16 && ret > 0) + return -EPROTO; + + return ret == 16 ? 0 : ret; +} + +static void build_mst_prop_path(const struct drm_dp_mst_branch *mstb, + int pnum, + char *proppath, + size_t proppath_size) +{ + int i; + char temp[8]; + + snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id); + for (i = 0; i < (mstb->lct - 1); i++) { + int shift = (i % 2) ? 0 : 4; + int port_num = (mstb->rad[i / 2] >> shift) & 0xf; + + snprintf(temp, sizeof(temp), "-%d", port_num); + strlcat(proppath, temp, proppath_size); + } + snprintf(temp, sizeof(temp), "-%d", pnum); + strlcat(proppath, temp, proppath_size); +} + +/** + * drm_dp_mst_connector_late_register() - Late MST connector registration + * @connector: The MST connector + * @port: The MST port for this connector + * + * Helper to register the remote aux device for this MST port. Drivers should + * call this from their mst connector's late_register hook to enable MST aux + * devices. + * + * Return: 0 on success, negative error code on failure. + */ +int drm_dp_mst_connector_late_register(struct drm_connector *connector, + struct drm_dp_mst_port *port) +{ + drm_dbg_kms(port->mgr->dev, "registering %s remote bus for %s\n", + port->aux.name, connector->kdev->kobj.name); + + port->aux.dev = connector->kdev; + return drm_dp_aux_register_devnode(&port->aux); +} +EXPORT_SYMBOL(drm_dp_mst_connector_late_register); + +/** + * drm_dp_mst_connector_early_unregister() - Early MST connector unregistration + * @connector: The MST connector + * @port: The MST port for this connector + * + * Helper to unregister the remote aux device for this MST port, registered by + * drm_dp_mst_connector_late_register(). Drivers should call this from their mst + * connector's early_unregister hook. + */ +void drm_dp_mst_connector_early_unregister(struct drm_connector *connector, + struct drm_dp_mst_port *port) +{ + drm_dbg_kms(port->mgr->dev, "unregistering %s remote bus for %s\n", + port->aux.name, connector->kdev->kobj.name); + drm_dp_aux_unregister_devnode(&port->aux); +} +EXPORT_SYMBOL(drm_dp_mst_connector_early_unregister); + +static void +drm_dp_mst_port_add_connector(struct drm_dp_mst_branch *mstb, + struct drm_dp_mst_port *port) +{ + struct drm_dp_mst_topology_mgr *mgr = port->mgr; + char proppath[255]; + int ret; + + build_mst_prop_path(mstb, port->port_num, proppath, sizeof(proppath)); + port->connector = mgr->cbs->add_connector(mgr, port, proppath); + if (!port->connector) { + ret = -ENOMEM; + goto error; + } + + if (port->pdt != DP_PEER_DEVICE_NONE && + drm_dp_mst_is_end_device(port->pdt, port->mcs) && + port->port_num >= DP_MST_LOGICAL_PORT_0) + port->cached_edid = drm_get_edid(port->connector, + &port->aux.ddc); + + drm_connector_register(port->connector); + return; + +error: + drm_err(mgr->dev, "Failed to create connector for port %p: %d\n", port, ret); +} + +/* + * Drop a topology reference, and unlink the port from the in-memory topology + * layout + */ +static void +drm_dp_mst_topology_unlink_port(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port) +{ + mutex_lock(&mgr->lock); + port->parent->num_ports--; + list_del(&port->next); + mutex_unlock(&mgr->lock); + drm_dp_mst_topology_put_port(port); +} + +static struct drm_dp_mst_port * +drm_dp_mst_add_port(struct drm_device *dev, + struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_branch *mstb, u8 port_number) +{ + struct drm_dp_mst_port *port = kzalloc(sizeof(*port), GFP_KERNEL); + + if (!port) + return NULL; + + kref_init(&port->topology_kref); + kref_init(&port->malloc_kref); + port->parent = mstb; + port->port_num = port_number; + port->mgr = mgr; + port->aux.name = "DPMST"; + port->aux.dev = dev->dev; + port->aux.is_remote = true; + + /* initialize the MST downstream port's AUX crc work queue */ + port->aux.drm_dev = dev; + drm_dp_remote_aux_init(&port->aux); + + /* + * Make sure the memory allocation for our parent branch stays + * around until our own memory allocation is released + */ + drm_dp_mst_get_mstb_malloc(mstb); + + return port; +} + +static int +drm_dp_mst_handle_link_address_port(struct drm_dp_mst_branch *mstb, + struct drm_device *dev, + struct drm_dp_link_addr_reply_port *port_msg) +{ + struct drm_dp_mst_topology_mgr *mgr = mstb->mgr; + struct drm_dp_mst_port *port; + int old_ddps = 0, ret; + u8 new_pdt = DP_PEER_DEVICE_NONE; + bool new_mcs = 0; + bool created = false, send_link_addr = false, changed = false; + + port = drm_dp_get_port(mstb, port_msg->port_number); + if (!port) { + port = drm_dp_mst_add_port(dev, mgr, mstb, + port_msg->port_number); + if (!port) + return -ENOMEM; + created = true; + changed = true; + } else if (!port->input && port_msg->input_port && port->connector) { + /* Since port->connector can't be changed here, we create a + * new port if input_port changes from 0 to 1 + */ + drm_dp_mst_topology_unlink_port(mgr, port); + drm_dp_mst_topology_put_port(port); + port = drm_dp_mst_add_port(dev, mgr, mstb, + port_msg->port_number); + if (!port) + return -ENOMEM; + changed = true; + created = true; + } else if (port->input && !port_msg->input_port) { + changed = true; + } else if (port->connector) { + /* We're updating a port that's exposed to userspace, so do it + * under lock + */ + drm_modeset_lock(&mgr->base.lock, NULL); + + old_ddps = port->ddps; + changed = port->ddps != port_msg->ddps || + (port->ddps && + (port->ldps != port_msg->legacy_device_plug_status || + port->dpcd_rev != port_msg->dpcd_revision || + port->mcs != port_msg->mcs || + port->pdt != port_msg->peer_device_type || + port->num_sdp_stream_sinks != + port_msg->num_sdp_stream_sinks)); + } + + port->input = port_msg->input_port; + if (!port->input) + new_pdt = port_msg->peer_device_type; + new_mcs = port_msg->mcs; + port->ddps = port_msg->ddps; + port->ldps = port_msg->legacy_device_plug_status; + port->dpcd_rev = port_msg->dpcd_revision; + port->num_sdp_streams = port_msg->num_sdp_streams; + port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks; + + /* manage mstb port lists with mgr lock - take a reference + for this list */ + if (created) { + mutex_lock(&mgr->lock); + drm_dp_mst_topology_get_port(port); + list_add(&port->next, &mstb->ports); + mstb->num_ports++; + mutex_unlock(&mgr->lock); + } + + /* + * Reprobe PBN caps on both hotplug, and when re-probing the link + * for our parent mstb + */ + if (old_ddps != port->ddps || !created) { + if (port->ddps && !port->input) { + ret = drm_dp_send_enum_path_resources(mgr, mstb, + port); + if (ret == 1) + changed = true; + } else { + port->full_pbn = 0; + } + } + + ret = drm_dp_port_set_pdt(port, new_pdt, new_mcs); + if (ret == 1) { + send_link_addr = true; + } else if (ret < 0) { + drm_err(dev, "Failed to change PDT on port %p: %d\n", port, ret); + goto fail; + } + + /* + * If this port wasn't just created, then we're reprobing because + * we're coming out of suspend. In this case, always resend the link + * address if there's an MSTB on this port + */ + if (!created && port->pdt == DP_PEER_DEVICE_MST_BRANCHING && + port->mcs) + send_link_addr = true; + + if (port->connector) + drm_modeset_unlock(&mgr->base.lock); + else if (!port->input) + drm_dp_mst_port_add_connector(mstb, port); + + if (send_link_addr && port->mstb) { + ret = drm_dp_send_link_address(mgr, port->mstb); + if (ret == 1) /* MSTB below us changed */ + changed = true; + else if (ret < 0) + goto fail_put; + } + + /* put reference to this port */ + drm_dp_mst_topology_put_port(port); + return changed; + +fail: + drm_dp_mst_topology_unlink_port(mgr, port); + if (port->connector) + drm_modeset_unlock(&mgr->base.lock); +fail_put: + drm_dp_mst_topology_put_port(port); + return ret; +} + +static int +drm_dp_mst_handle_conn_stat(struct drm_dp_mst_branch *mstb, + struct drm_dp_connection_status_notify *conn_stat) +{ + struct drm_dp_mst_topology_mgr *mgr = mstb->mgr; + struct drm_dp_mst_port *port; + int old_ddps, ret; + u8 new_pdt; + bool new_mcs; + bool dowork = false, create_connector = false; + + port = drm_dp_get_port(mstb, conn_stat->port_number); + if (!port) + return 0; + + if (port->connector) { + if (!port->input && conn_stat->input_port) { + /* + * We can't remove a connector from an already exposed + * port, so just throw the port out and make sure we + * reprobe the link address of it's parent MSTB + */ + drm_dp_mst_topology_unlink_port(mgr, port); + mstb->link_address_sent = false; + dowork = true; + goto out; + } + + /* Locking is only needed if the port's exposed to userspace */ + drm_modeset_lock(&mgr->base.lock, NULL); + } else if (port->input && !conn_stat->input_port) { + create_connector = true; + /* Reprobe link address so we get num_sdp_streams */ + mstb->link_address_sent = false; + dowork = true; + } + + old_ddps = port->ddps; + port->input = conn_stat->input_port; + port->ldps = conn_stat->legacy_device_plug_status; + port->ddps = conn_stat->displayport_device_plug_status; + + if (old_ddps != port->ddps) { + if (port->ddps && !port->input) + drm_dp_send_enum_path_resources(mgr, mstb, port); + else + port->full_pbn = 0; + } + + new_pdt = port->input ? DP_PEER_DEVICE_NONE : conn_stat->peer_device_type; + new_mcs = conn_stat->message_capability_status; + ret = drm_dp_port_set_pdt(port, new_pdt, new_mcs); + if (ret == 1) { + dowork = true; + } else if (ret < 0) { + drm_err(mgr->dev, "Failed to change PDT for port %p: %d\n", port, ret); + dowork = false; + } + + if (port->connector) + drm_modeset_unlock(&mgr->base.lock); + else if (create_connector) + drm_dp_mst_port_add_connector(mstb, port); + +out: + drm_dp_mst_topology_put_port(port); + return dowork; +} + +static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr, + u8 lct, u8 *rad) +{ + struct drm_dp_mst_branch *mstb; + struct drm_dp_mst_port *port; + int i, ret; + /* find the port by iterating down */ + + mutex_lock(&mgr->lock); + mstb = mgr->mst_primary; + + if (!mstb) + goto out; + + for (i = 0; i < lct - 1; i++) { + int shift = (i % 2) ? 0 : 4; + int port_num = (rad[i / 2] >> shift) & 0xf; + + list_for_each_entry(port, &mstb->ports, next) { + if (port->port_num == port_num) { + mstb = port->mstb; + if (!mstb) { + drm_err(mgr->dev, + "failed to lookup MSTB with lct %d, rad %02x\n", + lct, rad[0]); + goto out; + } + + break; + } + } + } + ret = drm_dp_mst_topology_try_get_mstb(mstb); + if (!ret) + mstb = NULL; +out: + mutex_unlock(&mgr->lock); + return mstb; +} + +static struct drm_dp_mst_branch *get_mst_branch_device_by_guid_helper( + struct drm_dp_mst_branch *mstb, + const uint8_t *guid) +{ + struct drm_dp_mst_branch *found_mstb; + struct drm_dp_mst_port *port; + + if (!mstb) + return NULL; + + if (memcmp(mstb->guid, guid, 16) == 0) + return mstb; + + + list_for_each_entry(port, &mstb->ports, next) { + found_mstb = get_mst_branch_device_by_guid_helper(port->mstb, guid); + + if (found_mstb) + return found_mstb; + } + + return NULL; +} + +static struct drm_dp_mst_branch * +drm_dp_get_mst_branch_device_by_guid(struct drm_dp_mst_topology_mgr *mgr, + const uint8_t *guid) +{ + struct drm_dp_mst_branch *mstb; + int ret; + + /* find the port by iterating down */ + mutex_lock(&mgr->lock); + + mstb = get_mst_branch_device_by_guid_helper(mgr->mst_primary, guid); + if (mstb) { + ret = drm_dp_mst_topology_try_get_mstb(mstb); + if (!ret) + mstb = NULL; + } + + mutex_unlock(&mgr->lock); + return mstb; +} + +static int drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_branch *mstb) +{ + struct drm_dp_mst_port *port; + int ret; + bool changed = false; + + if (!mstb->link_address_sent) { + ret = drm_dp_send_link_address(mgr, mstb); + if (ret == 1) + changed = true; + else if (ret < 0) + return ret; + } + + list_for_each_entry(port, &mstb->ports, next) { + if (port->input || !port->ddps || !port->mstb) + continue; + + ret = drm_dp_check_and_send_link_address(mgr, port->mstb); + if (ret == 1) + changed = true; + else if (ret < 0) + return ret; + } + + return changed; +} + +static void drm_dp_mst_link_probe_work(struct work_struct *work) +{ + struct drm_dp_mst_topology_mgr *mgr = + container_of(work, struct drm_dp_mst_topology_mgr, work); + struct drm_device *dev = mgr->dev; + struct drm_dp_mst_branch *mstb; + int ret; + bool clear_payload_id_table; + + mutex_lock(&mgr->probe_lock); + + mutex_lock(&mgr->lock); + clear_payload_id_table = !mgr->payload_id_table_cleared; + mgr->payload_id_table_cleared = true; + + mstb = mgr->mst_primary; + if (mstb) { + ret = drm_dp_mst_topology_try_get_mstb(mstb); + if (!ret) + mstb = NULL; + } + mutex_unlock(&mgr->lock); + if (!mstb) { + mutex_unlock(&mgr->probe_lock); + return; + } + + /* + * Certain branch devices seem to incorrectly report an available_pbn + * of 0 on downstream sinks, even after clearing the + * DP_PAYLOAD_ALLOCATE_* registers in + * drm_dp_mst_topology_mgr_set_mst(). Namely, the CableMatters USB-C + * 2x DP hub. Sending a CLEAR_PAYLOAD_ID_TABLE message seems to make + * things work again. + */ + if (clear_payload_id_table) { + drm_dbg_kms(dev, "Clearing payload ID table\n"); + drm_dp_send_clear_payload_id_table(mgr, mstb); + } + + ret = drm_dp_check_and_send_link_address(mgr, mstb); + drm_dp_mst_topology_put_mstb(mstb); + + mutex_unlock(&mgr->probe_lock); + if (ret > 0) + drm_kms_helper_hotplug_event(dev); +} + +static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr, + u8 *guid) +{ + u64 salt; + + if (memchr_inv(guid, 0, 16)) + return true; + + salt = get_jiffies_64(); + + memcpy(&guid[0], &salt, sizeof(u64)); + memcpy(&guid[8], &salt, sizeof(u64)); + + return false; +} + +static void build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, + u8 port_num, u32 offset, u8 num_bytes) +{ + struct drm_dp_sideband_msg_req_body req; + + req.req_type = DP_REMOTE_DPCD_READ; + req.u.dpcd_read.port_number = port_num; + req.u.dpcd_read.dpcd_address = offset; + req.u.dpcd_read.num_bytes = num_bytes; + drm_dp_encode_sideband_req(&req, msg); +} + +static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr, + bool up, u8 *msg, int len) +{ + int ret; + int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE; + int tosend, total, offset; + int retries = 0; + +retry: + total = len; + offset = 0; + do { + tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total); + + ret = drm_dp_dpcd_write(mgr->aux, regbase + offset, + &msg[offset], + tosend); + if (ret != tosend) { + if (ret == -EIO && retries < 5) { + retries++; + goto retry; + } + drm_dbg_kms(mgr->dev, "failed to dpcd write %d %d\n", tosend, ret); + + return -EIO; + } + offset += tosend; + total -= tosend; + } while (total > 0); + return 0; +} + +static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr, + struct drm_dp_sideband_msg_tx *txmsg) +{ + struct drm_dp_mst_branch *mstb = txmsg->dst; + u8 req_type; + + req_type = txmsg->msg[0] & 0x7f; + if (req_type == DP_CONNECTION_STATUS_NOTIFY || + req_type == DP_RESOURCE_STATUS_NOTIFY || + req_type == DP_CLEAR_PAYLOAD_ID_TABLE) + hdr->broadcast = 1; + else + hdr->broadcast = 0; + hdr->path_msg = txmsg->path_msg; + if (hdr->broadcast) { + hdr->lct = 1; + hdr->lcr = 6; + } else { + hdr->lct = mstb->lct; + hdr->lcr = mstb->lct - 1; + } + + memcpy(hdr->rad, mstb->rad, hdr->lct / 2); + + return 0; +} +/* + * process a single block of the next message in the sideband queue + */ +static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_sideband_msg_tx *txmsg, + bool up) +{ + u8 chunk[48]; + struct drm_dp_sideband_msg_hdr hdr; + int len, space, idx, tosend; + int ret; + + if (txmsg->state == DRM_DP_SIDEBAND_TX_SENT) + return 0; + + memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr)); + + if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) + txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND; + + /* make hdr from dst mst */ + ret = set_hdr_from_dst_qlock(&hdr, txmsg); + if (ret < 0) + return ret; + + /* amount left to send in this message */ + len = txmsg->cur_len - txmsg->cur_offset; + + /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */ + space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr); + + tosend = min(len, space); + if (len == txmsg->cur_len) + hdr.somt = 1; + if (space >= len) + hdr.eomt = 1; + + + hdr.msg_len = tosend + 1; + drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx); + memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend); + /* add crc at end */ + drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend); + idx += tosend + 1; + + ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx); + if (ret) { + if (drm_debug_enabled(DRM_UT_DP)) { + struct drm_printer p = drm_debug_printer(DBG_PREFIX); + + drm_printf(&p, "sideband msg failed to send\n"); + drm_dp_mst_dump_sideband_msg_tx(&p, txmsg); + } + return ret; + } + + txmsg->cur_offset += tosend; + if (txmsg->cur_offset == txmsg->cur_len) { + txmsg->state = DRM_DP_SIDEBAND_TX_SENT; + return 1; + } + return 0; +} + +static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr) +{ + struct drm_dp_sideband_msg_tx *txmsg; + int ret; + + WARN_ON(!mutex_is_locked(&mgr->qlock)); + + /* construct a chunk from the first msg in the tx_msg queue */ + if (list_empty(&mgr->tx_msg_downq)) + return; + + txmsg = list_first_entry(&mgr->tx_msg_downq, + struct drm_dp_sideband_msg_tx, next); + ret = process_single_tx_qlock(mgr, txmsg, false); + if (ret < 0) { + drm_dbg_kms(mgr->dev, "failed to send msg in q %d\n", ret); + list_del(&txmsg->next); + txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT; + wake_up_all(&mgr->tx_waitq); + } +} + +static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_sideband_msg_tx *txmsg) +{ + mutex_lock(&mgr->qlock); + list_add_tail(&txmsg->next, &mgr->tx_msg_downq); + + if (drm_debug_enabled(DRM_UT_DP)) { + struct drm_printer p = drm_debug_printer(DBG_PREFIX); + + drm_dp_mst_dump_sideband_msg_tx(&p, txmsg); + } + + if (list_is_singular(&mgr->tx_msg_downq)) + process_single_down_tx_qlock(mgr); + mutex_unlock(&mgr->qlock); +} + +static void +drm_dp_dump_link_address(const struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_link_address_ack_reply *reply) +{ + struct drm_dp_link_addr_reply_port *port_reply; + int i; + + for (i = 0; i < reply->nports; i++) { + port_reply = &reply->ports[i]; + drm_dbg_kms(mgr->dev, + "port %d: input %d, pdt: %d, pn: %d, dpcd_rev: %02x, mcs: %d, ddps: %d, ldps %d, sdp %d/%d\n", + i, + port_reply->input_port, + port_reply->peer_device_type, + port_reply->port_number, + port_reply->dpcd_revision, + port_reply->mcs, + port_reply->ddps, + port_reply->legacy_device_plug_status, + port_reply->num_sdp_streams, + port_reply->num_sdp_stream_sinks); + } +} + +static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_branch *mstb) +{ + struct drm_dp_sideband_msg_tx *txmsg; + struct drm_dp_link_address_ack_reply *reply; + struct drm_dp_mst_port *port, *tmp; + int i, ret, port_mask = 0; + bool changed = false; + + txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); + if (!txmsg) + return -ENOMEM; + + txmsg->dst = mstb; + build_link_address(txmsg); + + mstb->link_address_sent = true; + drm_dp_queue_down_tx(mgr, txmsg); + + /* FIXME: Actually do some real error handling here */ + ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); + if (ret <= 0) { + drm_err(mgr->dev, "Sending link address failed with %d\n", ret); + goto out; + } + if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) { + drm_err(mgr->dev, "link address NAK received\n"); + ret = -EIO; + goto out; + } + + reply = &txmsg->reply.u.link_addr; + drm_dbg_kms(mgr->dev, "link address reply: %d\n", reply->nports); + drm_dp_dump_link_address(mgr, reply); + + ret = drm_dp_check_mstb_guid(mstb, reply->guid); + if (ret) { + char buf[64]; + + drm_dp_mst_rad_to_str(mstb->rad, mstb->lct, buf, sizeof(buf)); + drm_err(mgr->dev, "GUID check on %s failed: %d\n", buf, ret); + goto out; + } + + for (i = 0; i < reply->nports; i++) { + port_mask |= BIT(reply->ports[i].port_number); + ret = drm_dp_mst_handle_link_address_port(mstb, mgr->dev, + &reply->ports[i]); + if (ret == 1) + changed = true; + else if (ret < 0) + goto out; + } + + /* Prune any ports that are currently a part of mstb in our in-memory + * topology, but were not seen in this link address. Usually this + * means that they were removed while the topology was out of sync, + * e.g. during suspend/resume + */ + mutex_lock(&mgr->lock); + list_for_each_entry_safe(port, tmp, &mstb->ports, next) { + if (port_mask & BIT(port->port_num)) + continue; + + drm_dbg_kms(mgr->dev, "port %d was not in link address, removing\n", + port->port_num); + list_del(&port->next); + drm_dp_mst_topology_put_port(port); + changed = true; + } + mutex_unlock(&mgr->lock); + +out: + if (ret <= 0) + mstb->link_address_sent = false; + kfree(txmsg); + return ret < 0 ? ret : changed; +} + +static void +drm_dp_send_clear_payload_id_table(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_branch *mstb) +{ + struct drm_dp_sideband_msg_tx *txmsg; + int ret; + + txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); + if (!txmsg) + return; + + txmsg->dst = mstb; + build_clear_payload_id_table(txmsg); + + drm_dp_queue_down_tx(mgr, txmsg); + + ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); + if (ret > 0 && txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) + drm_dbg_kms(mgr->dev, "clear payload table id nak received\n"); + + kfree(txmsg); +} + +static int +drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_branch *mstb, + struct drm_dp_mst_port *port) +{ + struct drm_dp_enum_path_resources_ack_reply *path_res; + struct drm_dp_sideband_msg_tx *txmsg; + int ret; + + txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); + if (!txmsg) + return -ENOMEM; + + txmsg->dst = mstb; + build_enum_path_resources(txmsg, port->port_num); + + drm_dp_queue_down_tx(mgr, txmsg); + + ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); + if (ret > 0) { + ret = 0; + path_res = &txmsg->reply.u.path_resources; + + if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) { + drm_dbg_kms(mgr->dev, "enum path resources nak received\n"); + } else { + if (port->port_num != path_res->port_number) + DRM_ERROR("got incorrect port in response\n"); + + drm_dbg_kms(mgr->dev, "enum path resources %d: %d %d\n", + path_res->port_number, + path_res->full_payload_bw_number, + path_res->avail_payload_bw_number); + + /* + * If something changed, make sure we send a + * hotplug + */ + if (port->full_pbn != path_res->full_payload_bw_number || + port->fec_capable != path_res->fec_capable) + ret = 1; + + port->full_pbn = path_res->full_payload_bw_number; + port->fec_capable = path_res->fec_capable; + } + } + + kfree(txmsg); + return ret; +} + +static struct drm_dp_mst_port *drm_dp_get_last_connected_port_to_mstb(struct drm_dp_mst_branch *mstb) +{ + if (!mstb->port_parent) + return NULL; + + if (mstb->port_parent->mstb != mstb) + return mstb->port_parent; + + return drm_dp_get_last_connected_port_to_mstb(mstb->port_parent->parent); +} + +/* + * Searches upwards in the topology starting from mstb to try to find the + * closest available parent of mstb that's still connected to the rest of the + * topology. This can be used in order to perform operations like releasing + * payloads, where the branch device which owned the payload may no longer be + * around and thus would require that the payload on the last living relative + * be freed instead. + */ +static struct drm_dp_mst_branch * +drm_dp_get_last_connected_port_and_mstb(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_branch *mstb, + int *port_num) +{ + struct drm_dp_mst_branch *rmstb = NULL; + struct drm_dp_mst_port *found_port; + + mutex_lock(&mgr->lock); + if (!mgr->mst_primary) + goto out; + + do { + found_port = drm_dp_get_last_connected_port_to_mstb(mstb); + if (!found_port) + break; + + if (drm_dp_mst_topology_try_get_mstb(found_port->parent)) { + rmstb = found_port->parent; + *port_num = found_port->port_num; + } else { + /* Search again, starting from this parent */ + mstb = found_port->parent; + } + } while (!rmstb); +out: + mutex_unlock(&mgr->lock); + return rmstb; +} + +static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port, + int id, + int pbn) +{ + struct drm_dp_sideband_msg_tx *txmsg; + struct drm_dp_mst_branch *mstb; + int ret, port_num; + u8 sinks[DRM_DP_MAX_SDP_STREAMS]; + int i; + + port_num = port->port_num; + mstb = drm_dp_mst_topology_get_mstb_validated(mgr, port->parent); + if (!mstb) { + mstb = drm_dp_get_last_connected_port_and_mstb(mgr, + port->parent, + &port_num); + + if (!mstb) + return -EINVAL; + } + + txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); + if (!txmsg) { + ret = -ENOMEM; + goto fail_put; + } + + for (i = 0; i < port->num_sdp_streams; i++) + sinks[i] = i; + + txmsg->dst = mstb; + build_allocate_payload(txmsg, port_num, + id, + pbn, port->num_sdp_streams, sinks); + + drm_dp_queue_down_tx(mgr, txmsg); + + /* + * FIXME: there is a small chance that between getting the last + * connected mstb and sending the payload message, the last connected + * mstb could also be removed from the topology. In the future, this + * needs to be fixed by restarting the + * drm_dp_get_last_connected_port_and_mstb() search in the event of a + * timeout if the topology is still connected to the system. + */ + ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); + if (ret > 0) { + if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) + ret = -EINVAL; + else + ret = 0; + } + kfree(txmsg); +fail_put: + drm_dp_mst_topology_put_mstb(mstb); + return ret; +} + +int drm_dp_send_power_updown_phy(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port, bool power_up) +{ + struct drm_dp_sideband_msg_tx *txmsg; + int ret; + + port = drm_dp_mst_topology_get_port_validated(mgr, port); + if (!port) + return -EINVAL; + + txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); + if (!txmsg) { + drm_dp_mst_topology_put_port(port); + return -ENOMEM; + } + + txmsg->dst = port->parent; + build_power_updown_phy(txmsg, port->port_num, power_up); + drm_dp_queue_down_tx(mgr, txmsg); + + ret = drm_dp_mst_wait_tx_reply(port->parent, txmsg); + if (ret > 0) { + if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) + ret = -EINVAL; + else + ret = 0; + } + kfree(txmsg); + drm_dp_mst_topology_put_port(port); + + return ret; +} +EXPORT_SYMBOL(drm_dp_send_power_updown_phy); + +int drm_dp_send_query_stream_enc_status(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port, + struct drm_dp_query_stream_enc_status_ack_reply *status) +{ + struct drm_dp_mst_topology_state *state; + struct drm_dp_mst_atomic_payload *payload; + struct drm_dp_sideband_msg_tx *txmsg; + u8 nonce[7]; + int ret; + + txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); + if (!txmsg) + return -ENOMEM; + + port = drm_dp_mst_topology_get_port_validated(mgr, port); + if (!port) { + ret = -EINVAL; + goto out_get_port; + } + + get_random_bytes(nonce, sizeof(nonce)); + + drm_modeset_lock(&mgr->base.lock, NULL); + state = to_drm_dp_mst_topology_state(mgr->base.state); + payload = drm_atomic_get_mst_payload_state(state, port); + + /* + * "Source device targets the QUERY_STREAM_ENCRYPTION_STATUS message + * transaction at the MST Branch device directly connected to the + * Source" + */ + txmsg->dst = mgr->mst_primary; + + build_query_stream_enc_status(txmsg, payload->vcpi, nonce); + + drm_dp_queue_down_tx(mgr, txmsg); + + ret = drm_dp_mst_wait_tx_reply(mgr->mst_primary, txmsg); + if (ret < 0) { + goto out; + } else if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) { + drm_dbg_kms(mgr->dev, "query encryption status nak received\n"); + ret = -ENXIO; + goto out; + } + + ret = 0; + memcpy(status, &txmsg->reply.u.enc_status, sizeof(*status)); + +out: + drm_modeset_unlock(&mgr->base.lock); + drm_dp_mst_topology_put_port(port); +out_get_port: + kfree(txmsg); + return ret; +} +EXPORT_SYMBOL(drm_dp_send_query_stream_enc_status); + +static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_atomic_payload *payload) +{ + return drm_dp_dpcd_write_payload(mgr, payload->vcpi, payload->vc_start_slot, + payload->time_slots); +} + +static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_atomic_payload *payload) +{ + int ret; + struct drm_dp_mst_port *port = drm_dp_mst_topology_get_port_validated(mgr, payload->port); + + if (!port) + return -EIO; + + ret = drm_dp_payload_send_msg(mgr, port, payload->vcpi, payload->pbn); + drm_dp_mst_topology_put_port(port); + return ret; +} + +static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_topology_state *mst_state, + struct drm_dp_mst_atomic_payload *payload) +{ + drm_dbg_kms(mgr->dev, "\n"); + + /* it's okay for these to fail */ + drm_dp_payload_send_msg(mgr, payload->port, payload->vcpi, 0); + drm_dp_dpcd_write_payload(mgr, payload->vcpi, payload->vc_start_slot, 0); + + return 0; +} + +/** + * drm_dp_add_payload_part1() - Execute payload update part 1 + * @mgr: Manager to use. + * @mst_state: The MST atomic state + * @payload: The payload to write + * + * Determines the starting time slot for the given payload, and programs the VCPI for this payload + * into hardware. After calling this, the driver should generate ACT and payload packets. + * + * Returns: 0 on success, error code on failure. In the event that this fails, + * @payload.vc_start_slot will also be set to -1. + */ +int drm_dp_add_payload_part1(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_topology_state *mst_state, + struct drm_dp_mst_atomic_payload *payload) +{ + struct drm_dp_mst_port *port; + int ret; + + port = drm_dp_mst_topology_get_port_validated(mgr, payload->port); + if (!port) { + drm_dbg_kms(mgr->dev, + "VCPI %d for port %p not in topology, not creating a payload\n", + payload->vcpi, payload->port); + payload->vc_start_slot = -1; + return 0; + } + + if (mgr->payload_count == 0) + mgr->next_start_slot = mst_state->start_slot; + + payload->vc_start_slot = mgr->next_start_slot; + + ret = drm_dp_create_payload_step1(mgr, payload); + drm_dp_mst_topology_put_port(port); + if (ret < 0) { + drm_warn(mgr->dev, "Failed to create MST payload for port %p: %d\n", + payload->port, ret); + payload->vc_start_slot = -1; + return ret; + } + + mgr->payload_count++; + mgr->next_start_slot += payload->time_slots; + + return 0; +} +EXPORT_SYMBOL(drm_dp_add_payload_part1); + +/** + * drm_dp_remove_payload() - Remove an MST payload + * @mgr: Manager to use. + * @mst_state: The MST atomic state + * @old_payload: The payload with its old state + * @new_payload: The payload to write + * + * Removes a payload from an MST topology if it was successfully assigned a start slot. Also updates + * the starting time slots of all other payloads which would have been shifted towards the start of + * the VC table as a result. After calling this, the driver should generate ACT and payload packets. + */ +void drm_dp_remove_payload(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_topology_state *mst_state, + const struct drm_dp_mst_atomic_payload *old_payload, + struct drm_dp_mst_atomic_payload *new_payload) +{ + struct drm_dp_mst_atomic_payload *pos; + bool send_remove = false; + + /* We failed to make the payload, so nothing to do */ + if (new_payload->vc_start_slot == -1) + return; + + mutex_lock(&mgr->lock); + send_remove = drm_dp_mst_port_downstream_of_branch(new_payload->port, mgr->mst_primary); + mutex_unlock(&mgr->lock); + + if (send_remove) + drm_dp_destroy_payload_step1(mgr, mst_state, new_payload); + else + drm_dbg_kms(mgr->dev, "Payload for VCPI %d not in topology, not sending remove\n", + new_payload->vcpi); + + list_for_each_entry(pos, &mst_state->payloads, next) { + if (pos != new_payload && pos->vc_start_slot > new_payload->vc_start_slot) + pos->vc_start_slot -= old_payload->time_slots; + } + new_payload->vc_start_slot = -1; + + mgr->payload_count--; + mgr->next_start_slot -= old_payload->time_slots; + + if (new_payload->delete) + drm_dp_mst_put_port_malloc(new_payload->port); +} +EXPORT_SYMBOL(drm_dp_remove_payload); + +/** + * drm_dp_add_payload_part2() - Execute payload update part 2 + * @mgr: Manager to use. + * @state: The global atomic state + * @payload: The payload to update + * + * If @payload was successfully assigned a starting time slot by drm_dp_add_payload_part1(), this + * function will send the sideband messages to finish allocating this payload. + * + * Returns: 0 on success, negative error code on failure. + */ +int drm_dp_add_payload_part2(struct drm_dp_mst_topology_mgr *mgr, + struct drm_atomic_state *state, + struct drm_dp_mst_atomic_payload *payload) +{ + int ret = 0; + + /* Skip failed payloads */ + if (payload->vc_start_slot == -1) { + drm_dbg_kms(mgr->dev, "Part 1 of payload creation for %s failed, skipping part 2\n", + payload->port->connector->name); + return -EIO; + } + + ret = drm_dp_create_payload_step2(mgr, payload); + if (ret < 0) { + if (!payload->delete) + drm_err(mgr->dev, "Step 2 of creating MST payload for %p failed: %d\n", + payload->port, ret); + else + drm_dbg_kms(mgr->dev, "Step 2 of removing MST payload for %p failed: %d\n", + payload->port, ret); + } + + return ret; +} +EXPORT_SYMBOL(drm_dp_add_payload_part2); + +static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port, + int offset, int size, u8 *bytes) +{ + int ret = 0; + struct drm_dp_sideband_msg_tx *txmsg; + struct drm_dp_mst_branch *mstb; + + mstb = drm_dp_mst_topology_get_mstb_validated(mgr, port->parent); + if (!mstb) + return -EINVAL; + + txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); + if (!txmsg) { + ret = -ENOMEM; + goto fail_put; + } + + build_dpcd_read(txmsg, port->port_num, offset, size); + txmsg->dst = port->parent; + + drm_dp_queue_down_tx(mgr, txmsg); + + ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); + if (ret < 0) + goto fail_free; + + if (txmsg->reply.reply_type == 1) { + drm_dbg_kms(mgr->dev, "mstb %p port %d: DPCD read on addr 0x%x for %d bytes NAKed\n", + mstb, port->port_num, offset, size); + ret = -EIO; + goto fail_free; + } + + if (txmsg->reply.u.remote_dpcd_read_ack.num_bytes != size) { + ret = -EPROTO; + goto fail_free; + } + + ret = min_t(size_t, txmsg->reply.u.remote_dpcd_read_ack.num_bytes, + size); + memcpy(bytes, txmsg->reply.u.remote_dpcd_read_ack.bytes, ret); + +fail_free: + kfree(txmsg); +fail_put: + drm_dp_mst_topology_put_mstb(mstb); + + return ret; +} + +static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port, + int offset, int size, u8 *bytes) +{ + int ret; + struct drm_dp_sideband_msg_tx *txmsg; + struct drm_dp_mst_branch *mstb; + + mstb = drm_dp_mst_topology_get_mstb_validated(mgr, port->parent); + if (!mstb) + return -EINVAL; + + txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); + if (!txmsg) { + ret = -ENOMEM; + goto fail_put; + } + + build_dpcd_write(txmsg, port->port_num, offset, size, bytes); + txmsg->dst = mstb; + + drm_dp_queue_down_tx(mgr, txmsg); + + ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); + if (ret > 0) { + if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) + ret = -EIO; + else + ret = size; + } + + kfree(txmsg); +fail_put: + drm_dp_mst_topology_put_mstb(mstb); + return ret; +} + +static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type) +{ + struct drm_dp_sideband_msg_reply_body reply; + + reply.reply_type = DP_SIDEBAND_REPLY_ACK; + reply.req_type = req_type; + drm_dp_encode_sideband_reply(&reply, msg); + return 0; +} + +static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_branch *mstb, + int req_type, bool broadcast) +{ + struct drm_dp_sideband_msg_tx *txmsg; + + txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); + if (!txmsg) + return -ENOMEM; + + txmsg->dst = mstb; + drm_dp_encode_up_ack_reply(txmsg, req_type); + + mutex_lock(&mgr->qlock); + /* construct a chunk from the first msg in the tx_msg queue */ + process_single_tx_qlock(mgr, txmsg, true); + mutex_unlock(&mgr->qlock); + + kfree(txmsg); + return 0; +} + +/** + * drm_dp_get_vc_payload_bw - get the VC payload BW for an MST link + * @mgr: The &drm_dp_mst_topology_mgr to use + * @link_rate: link rate in 10kbits/s units + * @link_lane_count: lane count + * + * Calculate the total bandwidth of a MultiStream Transport link. The returned + * value is in units of PBNs/(timeslots/1 MTP). This value can be used to + * convert the number of PBNs required for a given stream to the number of + * timeslots this stream requires in each MTP. + */ +int drm_dp_get_vc_payload_bw(const struct drm_dp_mst_topology_mgr *mgr, + int link_rate, int link_lane_count) +{ + if (link_rate == 0 || link_lane_count == 0) + drm_dbg_kms(mgr->dev, "invalid link rate/lane count: (%d / %d)\n", + link_rate, link_lane_count); + + /* See DP v2.0 2.6.4.2, VCPayload_Bandwidth_for_OneTimeSlotPer_MTP_Allocation */ + return link_rate * link_lane_count / 54000; +} +EXPORT_SYMBOL(drm_dp_get_vc_payload_bw); + +/** + * drm_dp_read_mst_cap() - check whether or not a sink supports MST + * @aux: The DP AUX channel to use + * @dpcd: A cached copy of the DPCD capabilities for this sink + * + * Returns: %True if the sink supports MST, %false otherwise + */ +bool drm_dp_read_mst_cap(struct drm_dp_aux *aux, + const u8 dpcd[DP_RECEIVER_CAP_SIZE]) +{ + u8 mstm_cap; + + if (dpcd[DP_DPCD_REV] < DP_DPCD_REV_12) + return false; + + if (drm_dp_dpcd_readb(aux, DP_MSTM_CAP, &mstm_cap) != 1) + return false; + + return mstm_cap & DP_MST_CAP; +} +EXPORT_SYMBOL(drm_dp_read_mst_cap); + +/** + * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager + * @mgr: manager to set state for + * @mst_state: true to enable MST on this connector - false to disable. + * + * This is called by the driver when it detects an MST capable device plugged + * into a DP MST capable port, or when a DP MST capable device is unplugged. + */ +int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state) +{ + int ret = 0; + struct drm_dp_mst_branch *mstb = NULL; + + mutex_lock(&mgr->lock); + if (mst_state == mgr->mst_state) + goto out_unlock; + + mgr->mst_state = mst_state; + /* set the device into MST mode */ + if (mst_state) { + WARN_ON(mgr->mst_primary); + + /* get dpcd info */ + ret = drm_dp_read_dpcd_caps(mgr->aux, mgr->dpcd); + if (ret < 0) { + drm_dbg_kms(mgr->dev, "%s: failed to read DPCD, ret %d\n", + mgr->aux->name, ret); + goto out_unlock; + } + + /* add initial branch device at LCT 1 */ + mstb = drm_dp_add_mst_branch_device(1, NULL); + if (mstb == NULL) { + ret = -ENOMEM; + goto out_unlock; + } + mstb->mgr = mgr; + + /* give this the main reference */ + mgr->mst_primary = mstb; + drm_dp_mst_topology_get_mstb(mgr->mst_primary); + + ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, + DP_MST_EN | + DP_UP_REQ_EN | + DP_UPSTREAM_IS_SRC); + if (ret < 0) + goto out_unlock; + + /* Write reset payload */ + drm_dp_dpcd_write_payload(mgr, 0, 0, 0x3f); + + queue_work(system_long_wq, &mgr->work); + + ret = 0; + } else { + /* disable MST on the device */ + mstb = mgr->mst_primary; + mgr->mst_primary = NULL; + /* this can fail if the device is gone */ + drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0); + ret = 0; + mgr->payload_id_table_cleared = false; + + memset(&mgr->down_rep_recv, 0, sizeof(mgr->down_rep_recv)); + memset(&mgr->up_req_recv, 0, sizeof(mgr->up_req_recv)); + } + +out_unlock: + mutex_unlock(&mgr->lock); + if (mstb) + drm_dp_mst_topology_put_mstb(mstb); + return ret; + +} +EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst); + +static void +drm_dp_mst_topology_mgr_invalidate_mstb(struct drm_dp_mst_branch *mstb) +{ + struct drm_dp_mst_port *port; + + /* The link address will need to be re-sent on resume */ + mstb->link_address_sent = false; + + list_for_each_entry(port, &mstb->ports, next) + if (port->mstb) + drm_dp_mst_topology_mgr_invalidate_mstb(port->mstb); +} + +/** + * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager + * @mgr: manager to suspend + * + * This function tells the MST device that we can't handle UP messages + * anymore. This should stop it from sending any since we are suspended. + */ +void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr) +{ + mutex_lock(&mgr->lock); + drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, + DP_MST_EN | DP_UPSTREAM_IS_SRC); + mutex_unlock(&mgr->lock); + flush_work(&mgr->up_req_work); + flush_work(&mgr->work); + flush_work(&mgr->delayed_destroy_work); + + mutex_lock(&mgr->lock); + if (mgr->mst_state && mgr->mst_primary) + drm_dp_mst_topology_mgr_invalidate_mstb(mgr->mst_primary); + mutex_unlock(&mgr->lock); +} +EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend); + +/** + * drm_dp_mst_topology_mgr_resume() - resume the MST manager + * @mgr: manager to resume + * @sync: whether or not to perform topology reprobing synchronously + * + * This will fetch DPCD and see if the device is still there, + * if it is, it will rewrite the MSTM control bits, and return. + * + * If the device fails this returns -1, and the driver should do + * a full MST reprobe, in case we were undocked. + * + * During system resume (where it is assumed that the driver will be calling + * drm_atomic_helper_resume()) this function should be called beforehand with + * @sync set to true. In contexts like runtime resume where the driver is not + * expected to be calling drm_atomic_helper_resume(), this function should be + * called with @sync set to false in order to avoid deadlocking. + * + * Returns: -1 if the MST topology was removed while we were suspended, 0 + * otherwise. + */ +int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr, + bool sync) +{ + int ret; + u8 guid[16]; + + mutex_lock(&mgr->lock); + if (!mgr->mst_primary) + goto out_fail; + + if (drm_dp_read_dpcd_caps(mgr->aux, mgr->dpcd) < 0) { + drm_dbg_kms(mgr->dev, "dpcd read failed - undocked during suspend?\n"); + goto out_fail; + } + + ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, + DP_MST_EN | + DP_UP_REQ_EN | + DP_UPSTREAM_IS_SRC); + if (ret < 0) { + drm_dbg_kms(mgr->dev, "mst write failed - undocked during suspend?\n"); + goto out_fail; + } + + /* Some hubs forget their guids after they resume */ + ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, guid, 16); + if (ret != 16) { + drm_dbg_kms(mgr->dev, "dpcd read failed - undocked during suspend?\n"); + goto out_fail; + } + + ret = drm_dp_check_mstb_guid(mgr->mst_primary, guid); + if (ret) { + drm_dbg_kms(mgr->dev, "check mstb failed - undocked during suspend?\n"); + goto out_fail; + } + + /* + * For the final step of resuming the topology, we need to bring the + * state of our in-memory topology back into sync with reality. So, + * restart the probing process as if we're probing a new hub + */ + queue_work(system_long_wq, &mgr->work); + mutex_unlock(&mgr->lock); + + if (sync) { + drm_dbg_kms(mgr->dev, + "Waiting for link probe work to finish re-syncing topology...\n"); + flush_work(&mgr->work); + } + + return 0; + +out_fail: + mutex_unlock(&mgr->lock); + return -1; +} +EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume); + +static bool +drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up, + struct drm_dp_mst_branch **mstb) +{ + int len; + u8 replyblock[32]; + int replylen, curreply; + int ret; + u8 hdrlen; + struct drm_dp_sideband_msg_hdr hdr; + struct drm_dp_sideband_msg_rx *msg = + up ? &mgr->up_req_recv : &mgr->down_rep_recv; + int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : + DP_SIDEBAND_MSG_DOWN_REP_BASE; + + if (!up) + *mstb = NULL; + + len = min(mgr->max_dpcd_transaction_bytes, 16); + ret = drm_dp_dpcd_read(mgr->aux, basereg, replyblock, len); + if (ret != len) { + drm_dbg_kms(mgr->dev, "failed to read DPCD down rep %d %d\n", len, ret); + return false; + } + + ret = drm_dp_decode_sideband_msg_hdr(mgr, &hdr, replyblock, len, &hdrlen); + if (ret == false) { + print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, + 1, replyblock, len, false); + drm_dbg_kms(mgr->dev, "ERROR: failed header\n"); + return false; + } + + if (!up) { + /* Caller is responsible for giving back this reference */ + *mstb = drm_dp_get_mst_branch_device(mgr, hdr.lct, hdr.rad); + if (!*mstb) { + drm_dbg_kms(mgr->dev, "Got MST reply from unknown device %d\n", hdr.lct); + return false; + } + } + + if (!drm_dp_sideband_msg_set_header(msg, &hdr, hdrlen)) { + drm_dbg_kms(mgr->dev, "sideband msg set header failed %d\n", replyblock[0]); + return false; + } + + replylen = min(msg->curchunk_len, (u8)(len - hdrlen)); + ret = drm_dp_sideband_append_payload(msg, replyblock + hdrlen, replylen); + if (!ret) { + drm_dbg_kms(mgr->dev, "sideband msg build failed %d\n", replyblock[0]); + return false; + } + + replylen = msg->curchunk_len + msg->curchunk_hdrlen - len; + curreply = len; + while (replylen > 0) { + len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16); + ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply, + replyblock, len); + if (ret != len) { + drm_dbg_kms(mgr->dev, "failed to read a chunk (len %d, ret %d)\n", + len, ret); + return false; + } + + ret = drm_dp_sideband_append_payload(msg, replyblock, len); + if (!ret) { + drm_dbg_kms(mgr->dev, "failed to build sideband msg\n"); + return false; + } + + curreply += len; + replylen -= len; + } + return true; +} + +static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr) +{ + struct drm_dp_sideband_msg_tx *txmsg; + struct drm_dp_mst_branch *mstb = NULL; + struct drm_dp_sideband_msg_rx *msg = &mgr->down_rep_recv; + + if (!drm_dp_get_one_sb_msg(mgr, false, &mstb)) + goto out_clear_reply; + + /* Multi-packet message transmission, don't clear the reply */ + if (!msg->have_eomt) + goto out; + + /* find the message */ + mutex_lock(&mgr->qlock); + txmsg = list_first_entry_or_null(&mgr->tx_msg_downq, + struct drm_dp_sideband_msg_tx, next); + mutex_unlock(&mgr->qlock); + + /* Were we actually expecting a response, and from this mstb? */ + if (!txmsg || txmsg->dst != mstb) { + struct drm_dp_sideband_msg_hdr *hdr; + + hdr = &msg->initial_hdr; + drm_dbg_kms(mgr->dev, "Got MST reply with no msg %p %d %d %02x %02x\n", + mstb, hdr->seqno, hdr->lct, hdr->rad[0], msg->msg[0]); + goto out_clear_reply; + } + + drm_dp_sideband_parse_reply(mgr, msg, &txmsg->reply); + + if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) { + drm_dbg_kms(mgr->dev, + "Got NAK reply: req 0x%02x (%s), reason 0x%02x (%s), nak data 0x%02x\n", + txmsg->reply.req_type, + drm_dp_mst_req_type_str(txmsg->reply.req_type), + txmsg->reply.u.nak.reason, + drm_dp_mst_nak_reason_str(txmsg->reply.u.nak.reason), + txmsg->reply.u.nak.nak_data); + } + + memset(msg, 0, sizeof(struct drm_dp_sideband_msg_rx)); + drm_dp_mst_topology_put_mstb(mstb); + + mutex_lock(&mgr->qlock); + txmsg->state = DRM_DP_SIDEBAND_TX_RX; + list_del(&txmsg->next); + mutex_unlock(&mgr->qlock); + + wake_up_all(&mgr->tx_waitq); + + return 0; + +out_clear_reply: + memset(msg, 0, sizeof(struct drm_dp_sideband_msg_rx)); +out: + if (mstb) + drm_dp_mst_topology_put_mstb(mstb); + + return 0; +} + +static inline bool +drm_dp_mst_process_up_req(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_pending_up_req *up_req) +{ + struct drm_dp_mst_branch *mstb = NULL; + struct drm_dp_sideband_msg_req_body *msg = &up_req->msg; + struct drm_dp_sideband_msg_hdr *hdr = &up_req->hdr; + bool hotplug = false, dowork = false; + + if (hdr->broadcast) { + const u8 *guid = NULL; + + if (msg->req_type == DP_CONNECTION_STATUS_NOTIFY) + guid = msg->u.conn_stat.guid; + else if (msg->req_type == DP_RESOURCE_STATUS_NOTIFY) + guid = msg->u.resource_stat.guid; + + if (guid) + mstb = drm_dp_get_mst_branch_device_by_guid(mgr, guid); + } else { + mstb = drm_dp_get_mst_branch_device(mgr, hdr->lct, hdr->rad); + } + + if (!mstb) { + drm_dbg_kms(mgr->dev, "Got MST reply from unknown device %d\n", hdr->lct); + return false; + } + + /* TODO: Add missing handler for DP_RESOURCE_STATUS_NOTIFY events */ + if (msg->req_type == DP_CONNECTION_STATUS_NOTIFY) { + dowork = drm_dp_mst_handle_conn_stat(mstb, &msg->u.conn_stat); + hotplug = true; + } + + drm_dp_mst_topology_put_mstb(mstb); + + if (dowork) + queue_work(system_long_wq, &mgr->work); + return hotplug; +} + +static void drm_dp_mst_up_req_work(struct work_struct *work) +{ + struct drm_dp_mst_topology_mgr *mgr = + container_of(work, struct drm_dp_mst_topology_mgr, + up_req_work); + struct drm_dp_pending_up_req *up_req; + bool send_hotplug = false; + + mutex_lock(&mgr->probe_lock); + while (true) { + mutex_lock(&mgr->up_req_lock); + up_req = list_first_entry_or_null(&mgr->up_req_list, + struct drm_dp_pending_up_req, + next); + if (up_req) + list_del(&up_req->next); + mutex_unlock(&mgr->up_req_lock); + + if (!up_req) + break; + + send_hotplug |= drm_dp_mst_process_up_req(mgr, up_req); + kfree(up_req); + } + mutex_unlock(&mgr->probe_lock); + + if (send_hotplug) + drm_kms_helper_hotplug_event(mgr->dev); +} + +static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr) +{ + struct drm_dp_pending_up_req *up_req; + + if (!drm_dp_get_one_sb_msg(mgr, true, NULL)) + goto out; + + if (!mgr->up_req_recv.have_eomt) + return 0; + + up_req = kzalloc(sizeof(*up_req), GFP_KERNEL); + if (!up_req) + return -ENOMEM; + + INIT_LIST_HEAD(&up_req->next); + + drm_dp_sideband_parse_req(mgr, &mgr->up_req_recv, &up_req->msg); + + if (up_req->msg.req_type != DP_CONNECTION_STATUS_NOTIFY && + up_req->msg.req_type != DP_RESOURCE_STATUS_NOTIFY) { + drm_dbg_kms(mgr->dev, "Received unknown up req type, ignoring: %x\n", + up_req->msg.req_type); + kfree(up_req); + goto out; + } + + drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, up_req->msg.req_type, + false); + + if (up_req->msg.req_type == DP_CONNECTION_STATUS_NOTIFY) { + const struct drm_dp_connection_status_notify *conn_stat = + &up_req->msg.u.conn_stat; + + drm_dbg_kms(mgr->dev, "Got CSN: pn: %d ldps:%d ddps: %d mcs: %d ip: %d pdt: %d\n", + conn_stat->port_number, + conn_stat->legacy_device_plug_status, + conn_stat->displayport_device_plug_status, + conn_stat->message_capability_status, + conn_stat->input_port, + conn_stat->peer_device_type); + } else if (up_req->msg.req_type == DP_RESOURCE_STATUS_NOTIFY) { + const struct drm_dp_resource_status_notify *res_stat = + &up_req->msg.u.resource_stat; + + drm_dbg_kms(mgr->dev, "Got RSN: pn: %d avail_pbn %d\n", + res_stat->port_number, + res_stat->available_pbn); + } + + up_req->hdr = mgr->up_req_recv.initial_hdr; + mutex_lock(&mgr->up_req_lock); + list_add_tail(&up_req->next, &mgr->up_req_list); + mutex_unlock(&mgr->up_req_lock); + queue_work(system_long_wq, &mgr->up_req_work); + +out: + memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); + return 0; +} + +/** + * drm_dp_mst_hpd_irq_handle_event() - MST hotplug IRQ handle MST event + * @mgr: manager to notify irq for. + * @esi: 4 bytes from SINK_COUNT_ESI + * @ack: 4 bytes used to ack events starting from SINK_COUNT_ESI + * @handled: whether the hpd interrupt was consumed or not + * + * This should be called from the driver when it detects a HPD IRQ, + * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The + * topology manager will process the sideband messages received + * as indicated in the DEVICE_SERVICE_IRQ_VECTOR_ESI0 and set the + * corresponding flags that Driver has to ack the DP receiver later. + * + * Note that driver shall also call + * drm_dp_mst_hpd_irq_send_new_request() if the 'handled' is set + * after calling this function, to try to kick off a new request in + * the queue if the previous message transaction is completed. + * + * See also: + * drm_dp_mst_hpd_irq_send_new_request() + */ +int drm_dp_mst_hpd_irq_handle_event(struct drm_dp_mst_topology_mgr *mgr, const u8 *esi, + u8 *ack, bool *handled) +{ + int ret = 0; + int sc; + *handled = false; + sc = DP_GET_SINK_COUNT(esi[0]); + + if (sc != mgr->sink_count) { + mgr->sink_count = sc; + *handled = true; + } + + if (esi[1] & DP_DOWN_REP_MSG_RDY) { + ret = drm_dp_mst_handle_down_rep(mgr); + *handled = true; + ack[1] |= DP_DOWN_REP_MSG_RDY; + } + + if (esi[1] & DP_UP_REQ_MSG_RDY) { + ret |= drm_dp_mst_handle_up_req(mgr); + *handled = true; + ack[1] |= DP_UP_REQ_MSG_RDY; + } + + return ret; +} +EXPORT_SYMBOL(drm_dp_mst_hpd_irq_handle_event); + +/** + * drm_dp_mst_hpd_irq_send_new_request() - MST hotplug IRQ kick off new request + * @mgr: manager to notify irq for. + * + * This should be called from the driver when mst irq event is handled + * and acked. Note that new down request should only be sent when + * previous message transaction is completed. Source is not supposed to generate + * interleaved message transactions. + */ +void drm_dp_mst_hpd_irq_send_new_request(struct drm_dp_mst_topology_mgr *mgr) +{ + struct drm_dp_sideband_msg_tx *txmsg; + bool kick = true; + + mutex_lock(&mgr->qlock); + txmsg = list_first_entry_or_null(&mgr->tx_msg_downq, + struct drm_dp_sideband_msg_tx, next); + /* If last transaction is not completed yet*/ + if (!txmsg || + txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND || + txmsg->state == DRM_DP_SIDEBAND_TX_SENT) + kick = false; + mutex_unlock(&mgr->qlock); + + if (kick) + drm_dp_mst_kick_tx(mgr); +} +EXPORT_SYMBOL(drm_dp_mst_hpd_irq_send_new_request); +/** + * drm_dp_mst_detect_port() - get connection status for an MST port + * @connector: DRM connector for this port + * @ctx: The acquisition context to use for grabbing locks + * @mgr: manager for this port + * @port: pointer to a port + * + * This returns the current connection state for a port. + */ +int +drm_dp_mst_detect_port(struct drm_connector *connector, + struct drm_modeset_acquire_ctx *ctx, + struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port) +{ + int ret; + + /* we need to search for the port in the mgr in case it's gone */ + port = drm_dp_mst_topology_get_port_validated(mgr, port); + if (!port) + return connector_status_disconnected; + + ret = drm_modeset_lock(&mgr->base.lock, ctx); + if (ret) + goto out; + + ret = connector_status_disconnected; + + if (!port->ddps) + goto out; + + switch (port->pdt) { + case DP_PEER_DEVICE_NONE: + break; + case DP_PEER_DEVICE_MST_BRANCHING: + if (!port->mcs) + ret = connector_status_connected; + break; + + case DP_PEER_DEVICE_SST_SINK: + ret = connector_status_connected; + /* for logical ports - cache the EDID */ + if (port->port_num >= DP_MST_LOGICAL_PORT_0 && !port->cached_edid) + port->cached_edid = drm_get_edid(connector, &port->aux.ddc); + break; + case DP_PEER_DEVICE_DP_LEGACY_CONV: + if (port->ldps) + ret = connector_status_connected; + break; + } +out: + drm_dp_mst_topology_put_port(port); + return ret; +} +EXPORT_SYMBOL(drm_dp_mst_detect_port); + +/** + * drm_dp_mst_get_edid() - get EDID for an MST port + * @connector: toplevel connector to get EDID for + * @mgr: manager for this port + * @port: unverified pointer to a port. + * + * This returns an EDID for the port connected to a connector, + * It validates the pointer still exists so the caller doesn't require a + * reference. + */ +struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) +{ + struct edid *edid = NULL; + + /* we need to search for the port in the mgr in case it's gone */ + port = drm_dp_mst_topology_get_port_validated(mgr, port); + if (!port) + return NULL; + + if (port->cached_edid) + edid = drm_edid_duplicate(port->cached_edid); + else { + edid = drm_get_edid(connector, &port->aux.ddc); + } + port->has_audio = drm_detect_monitor_audio(edid); + drm_dp_mst_topology_put_port(port); + return edid; +} +EXPORT_SYMBOL(drm_dp_mst_get_edid); + +/** + * drm_dp_atomic_find_time_slots() - Find and add time slots to the state + * @state: global atomic state + * @mgr: MST topology manager for the port + * @port: port to find time slots for + * @pbn: bandwidth required for the mode in PBN + * + * Allocates time slots to @port, replacing any previous time slot allocations it may + * have had. Any atomic drivers which support MST must call this function in + * their &drm_encoder_helper_funcs.atomic_check() callback unconditionally to + * change the current time slot allocation for the new state, and ensure the MST + * atomic state is added whenever the state of payloads in the topology changes. + * + * Allocations set by this function are not checked against the bandwidth + * restraints of @mgr until the driver calls drm_dp_mst_atomic_check(). + * + * Additionally, it is OK to call this function multiple times on the same + * @port as needed. It is not OK however, to call this function and + * drm_dp_atomic_release_time_slots() in the same atomic check phase. + * + * See also: + * drm_dp_atomic_release_time_slots() + * drm_dp_mst_atomic_check() + * + * Returns: + * Total slots in the atomic state assigned for this port, or a negative error + * code if the port no longer exists + */ +int drm_dp_atomic_find_time_slots(struct drm_atomic_state *state, + struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port, int pbn) +{ + struct drm_dp_mst_topology_state *topology_state; + struct drm_dp_mst_atomic_payload *payload = NULL; + struct drm_connector_state *conn_state; + int prev_slots = 0, prev_bw = 0, req_slots; + + topology_state = drm_atomic_get_mst_topology_state(state, mgr); + if (IS_ERR(topology_state)) + return PTR_ERR(topology_state); + + conn_state = drm_atomic_get_new_connector_state(state, port->connector); + topology_state->pending_crtc_mask |= drm_crtc_mask(conn_state->crtc); + + /* Find the current allocation for this port, if any */ + payload = drm_atomic_get_mst_payload_state(topology_state, port); + if (payload) { + prev_slots = payload->time_slots; + prev_bw = payload->pbn; + + /* + * This should never happen, unless the driver tries + * releasing and allocating the same timeslot allocation, + * which is an error + */ + if (drm_WARN_ON(mgr->dev, payload->delete)) { + drm_err(mgr->dev, + "cannot allocate and release time slots on [MST PORT:%p] in the same state\n", + port); + return -EINVAL; + } + } + + req_slots = DIV_ROUND_UP(pbn, topology_state->pbn_div); + + drm_dbg_atomic(mgr->dev, "[CONNECTOR:%d:%s] [MST PORT:%p] TU %d -> %d\n", + port->connector->base.id, port->connector->name, + port, prev_slots, req_slots); + drm_dbg_atomic(mgr->dev, "[CONNECTOR:%d:%s] [MST PORT:%p] PBN %d -> %d\n", + port->connector->base.id, port->connector->name, + port, prev_bw, pbn); + + /* Add the new allocation to the state, note the VCPI isn't assigned until the end */ + if (!payload) { + payload = kzalloc(sizeof(*payload), GFP_KERNEL); + if (!payload) + return -ENOMEM; + + drm_dp_mst_get_port_malloc(port); + payload->port = port; + payload->vc_start_slot = -1; + list_add(&payload->next, &topology_state->payloads); + } + payload->time_slots = req_slots; + payload->pbn = pbn; + + return req_slots; +} +EXPORT_SYMBOL(drm_dp_atomic_find_time_slots); + +/** + * drm_dp_atomic_release_time_slots() - Release allocated time slots + * @state: global atomic state + * @mgr: MST topology manager for the port + * @port: The port to release the time slots from + * + * Releases any time slots that have been allocated to a port in the atomic + * state. Any atomic drivers which support MST must call this function + * unconditionally in their &drm_connector_helper_funcs.atomic_check() callback. + * This helper will check whether time slots would be released by the new state and + * respond accordingly, along with ensuring the MST state is always added to the + * atomic state whenever a new state would modify the state of payloads on the + * topology. + * + * It is OK to call this even if @port has been removed from the system. + * Additionally, it is OK to call this function multiple times on the same + * @port as needed. It is not OK however, to call this function and + * drm_dp_atomic_find_time_slots() on the same @port in a single atomic check + * phase. + * + * See also: + * drm_dp_atomic_find_time_slots() + * drm_dp_mst_atomic_check() + * + * Returns: + * 0 on success, negative error code otherwise + */ +int drm_dp_atomic_release_time_slots(struct drm_atomic_state *state, + struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port) +{ + struct drm_dp_mst_topology_state *topology_state; + struct drm_dp_mst_atomic_payload *payload; + struct drm_connector_state *old_conn_state, *new_conn_state; + bool update_payload = true; + + old_conn_state = drm_atomic_get_old_connector_state(state, port->connector); + if (!old_conn_state->crtc) + return 0; + + /* If the CRTC isn't disabled by this state, don't release it's payload */ + new_conn_state = drm_atomic_get_new_connector_state(state, port->connector); + if (new_conn_state->crtc) { + struct drm_crtc_state *crtc_state = + drm_atomic_get_new_crtc_state(state, new_conn_state->crtc); + + /* No modeset means no payload changes, so it's safe to not pull in the MST state */ + if (!crtc_state || !drm_atomic_crtc_needs_modeset(crtc_state)) + return 0; + + if (!crtc_state->mode_changed && !crtc_state->connectors_changed) + update_payload = false; + } + + topology_state = drm_atomic_get_mst_topology_state(state, mgr); + if (IS_ERR(topology_state)) + return PTR_ERR(topology_state); + + topology_state->pending_crtc_mask |= drm_crtc_mask(old_conn_state->crtc); + if (!update_payload) + return 0; + + payload = drm_atomic_get_mst_payload_state(topology_state, port); + if (WARN_ON(!payload)) { + drm_err(mgr->dev, "No payload for [MST PORT:%p] found in mst state %p\n", + port, &topology_state->base); + return -EINVAL; + } + + if (new_conn_state->crtc) + return 0; + + drm_dbg_atomic(mgr->dev, "[MST PORT:%p] TU %d -> 0\n", port, payload->time_slots); + if (!payload->delete) { + payload->pbn = 0; + payload->delete = true; + topology_state->payload_mask &= ~BIT(payload->vcpi - 1); + } + + return 0; +} +EXPORT_SYMBOL(drm_dp_atomic_release_time_slots); + +/** + * drm_dp_mst_atomic_setup_commit() - setup_commit hook for MST helpers + * @state: global atomic state + * + * This function saves all of the &drm_crtc_commit structs in an atomic state that touch any CRTCs + * currently assigned to an MST topology. Drivers must call this hook from their + * &drm_mode_config_helper_funcs.atomic_commit_setup hook. + * + * Returns: + * 0 if all CRTC commits were retrieved successfully, negative error code otherwise + */ +int drm_dp_mst_atomic_setup_commit(struct drm_atomic_state *state) +{ + struct drm_dp_mst_topology_mgr *mgr; + struct drm_dp_mst_topology_state *mst_state; + struct drm_crtc *crtc; + struct drm_crtc_state *crtc_state; + int i, j, commit_idx, num_commit_deps; + + for_each_new_mst_mgr_in_state(state, mgr, mst_state, i) { + if (!mst_state->pending_crtc_mask) + continue; + + num_commit_deps = hweight32(mst_state->pending_crtc_mask); + mst_state->commit_deps = kmalloc_array(num_commit_deps, + sizeof(*mst_state->commit_deps), GFP_KERNEL); + if (!mst_state->commit_deps) + return -ENOMEM; + mst_state->num_commit_deps = num_commit_deps; + + commit_idx = 0; + for_each_new_crtc_in_state(state, crtc, crtc_state, j) { + if (mst_state->pending_crtc_mask & drm_crtc_mask(crtc)) { + mst_state->commit_deps[commit_idx++] = + drm_crtc_commit_get(crtc_state->commit); + } + } + } + + return 0; +} +EXPORT_SYMBOL(drm_dp_mst_atomic_setup_commit); + +/** + * drm_dp_mst_atomic_wait_for_dependencies() - Wait for all pending commits on MST topologies, + * prepare new MST state for commit + * @state: global atomic state + * + * Goes through any MST topologies in this atomic state, and waits for any pending commits which + * touched CRTCs that were/are on an MST topology to be programmed to hardware and flipped to before + * returning. This is to prevent multiple non-blocking commits affecting an MST topology from racing + * with eachother by forcing them to be executed sequentially in situations where the only resources + * the modeset objects in these commits share are an MST topology. + * + * This function also prepares the new MST state for commit by performing some state preparation + * which can't be done until this point, such as reading back the final VC start slots (which are + * determined at commit-time) from the previous state. + * + * All MST drivers must call this function after calling drm_atomic_helper_wait_for_dependencies(), + * or whatever their equivalent of that is. + */ +void drm_dp_mst_atomic_wait_for_dependencies(struct drm_atomic_state *state) +{ + struct drm_dp_mst_topology_state *old_mst_state, *new_mst_state; + struct drm_dp_mst_topology_mgr *mgr; + struct drm_dp_mst_atomic_payload *old_payload, *new_payload; + int i, j, ret; + + for_each_oldnew_mst_mgr_in_state(state, mgr, old_mst_state, new_mst_state, i) { + for (j = 0; j < old_mst_state->num_commit_deps; j++) { + ret = drm_crtc_commit_wait(old_mst_state->commit_deps[j]); + if (ret < 0) + drm_err(state->dev, "Failed to wait for %s: %d\n", + old_mst_state->commit_deps[j]->crtc->name, ret); + } + + /* Now that previous state is committed, it's safe to copy over the start slot + * assignments + */ + list_for_each_entry(old_payload, &old_mst_state->payloads, next) { + if (old_payload->delete) + continue; + + new_payload = drm_atomic_get_mst_payload_state(new_mst_state, + old_payload->port); + new_payload->vc_start_slot = old_payload->vc_start_slot; + } + } +} +EXPORT_SYMBOL(drm_dp_mst_atomic_wait_for_dependencies); + +/** + * drm_dp_mst_root_conn_atomic_check() - Serialize CRTC commits on MST-capable connectors operating + * in SST mode + * @new_conn_state: The new connector state of the &drm_connector + * @mgr: The MST topology manager for the &drm_connector + * + * Since MST uses fake &drm_encoder structs, the generic atomic modesetting code isn't able to + * serialize non-blocking commits happening on the real DP connector of an MST topology switching + * into/away from MST mode - as the CRTC on the real DP connector and the CRTCs on the connector's + * MST topology will never share the same &drm_encoder. + * + * This function takes care of this serialization issue, by checking a root MST connector's atomic + * state to determine if it is about to have a modeset - and then pulling in the MST topology state + * if so, along with adding any relevant CRTCs to &drm_dp_mst_topology_state.pending_crtc_mask. + * + * Drivers implementing MST must call this function from the + * &drm_connector_helper_funcs.atomic_check hook of any physical DP &drm_connector capable of + * driving MST sinks. + * + * Returns: + * 0 on success, negative error code otherwise + */ +int drm_dp_mst_root_conn_atomic_check(struct drm_connector_state *new_conn_state, + struct drm_dp_mst_topology_mgr *mgr) +{ + struct drm_atomic_state *state = new_conn_state->state; + struct drm_connector_state *old_conn_state = + drm_atomic_get_old_connector_state(state, new_conn_state->connector); + struct drm_crtc_state *crtc_state; + struct drm_dp_mst_topology_state *mst_state = NULL; + + if (new_conn_state->crtc) { + crtc_state = drm_atomic_get_new_crtc_state(state, new_conn_state->crtc); + if (crtc_state && drm_atomic_crtc_needs_modeset(crtc_state)) { + mst_state = drm_atomic_get_mst_topology_state(state, mgr); + if (IS_ERR(mst_state)) + return PTR_ERR(mst_state); + + mst_state->pending_crtc_mask |= drm_crtc_mask(new_conn_state->crtc); + } + } + + if (old_conn_state->crtc) { + crtc_state = drm_atomic_get_new_crtc_state(state, old_conn_state->crtc); + if (crtc_state && drm_atomic_crtc_needs_modeset(crtc_state)) { + if (!mst_state) { + mst_state = drm_atomic_get_mst_topology_state(state, mgr); + if (IS_ERR(mst_state)) + return PTR_ERR(mst_state); + } + + mst_state->pending_crtc_mask |= drm_crtc_mask(old_conn_state->crtc); + } + } + + return 0; +} +EXPORT_SYMBOL(drm_dp_mst_root_conn_atomic_check); + +/** + * drm_dp_mst_update_slots() - updates the slot info depending on the DP ecoding format + * @mst_state: mst_state to update + * @link_encoding_cap: the ecoding format on the link + */ +void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_encoding_cap) +{ + if (link_encoding_cap == DP_CAP_ANSI_128B132B) { + mst_state->total_avail_slots = 64; + mst_state->start_slot = 0; + } else { + mst_state->total_avail_slots = 63; + mst_state->start_slot = 1; + } + + DRM_DEBUG_KMS("%s encoding format on mst_state 0x%p\n", + (link_encoding_cap == DP_CAP_ANSI_128B132B) ? "128b/132b":"8b/10b", + mst_state); +} +EXPORT_SYMBOL(drm_dp_mst_update_slots); + +static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr, + int id, u8 start_slot, u8 num_slots) +{ + u8 payload_alloc[3], status; + int ret; + int retries = 0; + + drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, + DP_PAYLOAD_TABLE_UPDATED); + + payload_alloc[0] = id; + payload_alloc[1] = start_slot; + payload_alloc[2] = num_slots; + + ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3); + if (ret != 3) { + drm_dbg_kms(mgr->dev, "failed to write payload allocation %d\n", ret); + goto fail; + } + +retry: + ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status); + if (ret < 0) { + drm_dbg_kms(mgr->dev, "failed to read payload table status %d\n", ret); + goto fail; + } + + if (!(status & DP_PAYLOAD_TABLE_UPDATED)) { + retries++; + if (retries < 20) { + usleep_range(10000, 20000); + goto retry; + } + drm_dbg_kms(mgr->dev, "status not set after read payload table status %d\n", + status); + ret = -EINVAL; + goto fail; + } + ret = 0; +fail: + return ret; +} + +static int do_get_act_status(struct drm_dp_aux *aux) +{ + int ret; + u8 status; + + ret = drm_dp_dpcd_readb(aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status); + if (ret < 0) + return ret; + + return status; +} + +/** + * drm_dp_check_act_status() - Polls for ACT handled status. + * @mgr: manager to use + * + * Tries waiting for the MST hub to finish updating it's payload table by + * polling for the ACT handled bit for up to 3 seconds (yes-some hubs really + * take that long). + * + * Returns: + * 0 if the ACT was handled in time, negative error code on failure. + */ +int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr) +{ + /* + * There doesn't seem to be any recommended retry count or timeout in + * the MST specification. Since some hubs have been observed to take + * over 1 second to update their payload allocations under certain + * conditions, we use a rather large timeout value. + */ + const int timeout_ms = 3000; + int ret, status; + + ret = readx_poll_timeout(do_get_act_status, mgr->aux, status, + status & DP_PAYLOAD_ACT_HANDLED || status < 0, + 200, timeout_ms * USEC_PER_MSEC); + if (ret < 0 && status >= 0) { + drm_err(mgr->dev, "Failed to get ACT after %dms, last status: %02x\n", + timeout_ms, status); + return -EINVAL; + } else if (status < 0) { + /* + * Failure here isn't unexpected - the hub may have + * just been unplugged + */ + drm_dbg_kms(mgr->dev, "Failed to read payload table status: %d\n", status); + return status; + } + + return 0; +} +EXPORT_SYMBOL(drm_dp_check_act_status); + +/** + * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode. + * @clock: dot clock for the mode + * @bpp: bpp for the mode. + * @dsc: DSC mode. If true, bpp has units of 1/16 of a bit per pixel + * + * This uses the formula in the spec to calculate the PBN value for a mode. + */ +int drm_dp_calc_pbn_mode(int clock, int bpp, bool dsc) +{ + /* + * margin 5300ppm + 300ppm ~ 0.6% as per spec, factor is 1.006 + * The unit of 54/64Mbytes/sec is an arbitrary unit chosen based on + * common multiplier to render an integer PBN for all link rate/lane + * counts combinations + * calculate + * peak_kbps *= (1006/1000) + * peak_kbps *= (64/54) + * peak_kbps *= 8 convert to bytes + * + * If the bpp is in units of 1/16, further divide by 16. Put this + * factor in the numerator rather than the denominator to avoid + * integer overflow + */ + + if (dsc) + return DIV_ROUND_UP_ULL(mul_u32_u32(clock * (bpp / 16), 64 * 1006), + 8 * 54 * 1000 * 1000); + + return DIV_ROUND_UP_ULL(mul_u32_u32(clock * bpp, 64 * 1006), + 8 * 54 * 1000 * 1000); +} +EXPORT_SYMBOL(drm_dp_calc_pbn_mode); + +/* we want to kick the TX after we've ack the up/down IRQs. */ +static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr) +{ + queue_work(system_long_wq, &mgr->tx_work); +} + +/* + * Helper function for parsing DP device types into convenient strings + * for use with dp_mst_topology + */ +static const char *pdt_to_string(u8 pdt) +{ + switch (pdt) { + case DP_PEER_DEVICE_NONE: + return "NONE"; + case DP_PEER_DEVICE_SOURCE_OR_SST: + return "SOURCE OR SST"; + case DP_PEER_DEVICE_MST_BRANCHING: + return "MST BRANCHING"; + case DP_PEER_DEVICE_SST_SINK: + return "SST SINK"; + case DP_PEER_DEVICE_DP_LEGACY_CONV: + return "DP LEGACY CONV"; + default: + return "ERR"; + } +} + +static void drm_dp_mst_dump_mstb(struct seq_file *m, + struct drm_dp_mst_branch *mstb) +{ + struct drm_dp_mst_port *port; + int tabs = mstb->lct; + char prefix[10]; + int i; + + for (i = 0; i < tabs; i++) + prefix[i] = '\t'; + prefix[i] = '\0'; + + seq_printf(m, "%smstb - [%p]: num_ports: %d\n", prefix, mstb, mstb->num_ports); + list_for_each_entry(port, &mstb->ports, next) { + seq_printf(m, "%sport %d - [%p] (%s - %s): ddps: %d, ldps: %d, sdp: %d/%d, fec: %s, conn: %p\n", + prefix, + port->port_num, + port, + port->input ? "input" : "output", + pdt_to_string(port->pdt), + port->ddps, + port->ldps, + port->num_sdp_streams, + port->num_sdp_stream_sinks, + port->fec_capable ? "true" : "false", + port->connector); + if (port->mstb) + drm_dp_mst_dump_mstb(m, port->mstb); + } +} + +#define DP_PAYLOAD_TABLE_SIZE 64 + +static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr, + char *buf) +{ + int i; + + for (i = 0; i < DP_PAYLOAD_TABLE_SIZE; i += 16) { + if (drm_dp_dpcd_read(mgr->aux, + DP_PAYLOAD_TABLE_UPDATE_STATUS + i, + &buf[i], 16) != 16) + return false; + } + return true; +} + +static void fetch_monitor_name(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_port *port, char *name, + int namelen) +{ + struct edid *mst_edid; + + mst_edid = drm_dp_mst_get_edid(port->connector, mgr, port); + drm_edid_get_monitor_name(mst_edid, name, namelen); + kfree(mst_edid); +} + +/** + * drm_dp_mst_dump_topology(): dump topology to seq file. + * @m: seq_file to dump output to + * @mgr: manager to dump current topology for. + * + * helper to dump MST topology to a seq file for debugfs. + */ +void drm_dp_mst_dump_topology(struct seq_file *m, + struct drm_dp_mst_topology_mgr *mgr) +{ + struct drm_dp_mst_topology_state *state; + struct drm_dp_mst_atomic_payload *payload; + int i, ret; + + mutex_lock(&mgr->lock); + if (mgr->mst_primary) + drm_dp_mst_dump_mstb(m, mgr->mst_primary); + + /* dump VCPIs */ + mutex_unlock(&mgr->lock); + + ret = drm_modeset_lock_single_interruptible(&mgr->base.lock); + if (ret < 0) + return; + + state = to_drm_dp_mst_topology_state(mgr->base.state); + seq_printf(m, "\n*** Atomic state info ***\n"); + seq_printf(m, "payload_mask: %x, max_payloads: %d, start_slot: %u, pbn_div: %d\n", + state->payload_mask, mgr->max_payloads, state->start_slot, state->pbn_div); + + seq_printf(m, "\n| idx | port | vcpi | slots | pbn | dsc | sink name |\n"); + for (i = 0; i < mgr->max_payloads; i++) { + list_for_each_entry(payload, &state->payloads, next) { + char name[14]; + + if (payload->vcpi != i || payload->delete) + continue; + + fetch_monitor_name(mgr, payload->port, name, sizeof(name)); + seq_printf(m, " %5d %6d %6d %02d - %02d %5d %5s %19s\n", + i, + payload->port->port_num, + payload->vcpi, + payload->vc_start_slot, + payload->vc_start_slot + payload->time_slots - 1, + payload->pbn, + payload->dsc_enabled ? "Y" : "N", + (*name != 0) ? name : "Unknown"); + } + } + + seq_printf(m, "\n*** DPCD Info ***\n"); + mutex_lock(&mgr->lock); + if (mgr->mst_primary) { + u8 buf[DP_PAYLOAD_TABLE_SIZE]; + int ret; + + if (drm_dp_read_dpcd_caps(mgr->aux, buf) < 0) { + seq_printf(m, "dpcd read failed\n"); + goto out; + } + seq_printf(m, "dpcd: %*ph\n", DP_RECEIVER_CAP_SIZE, buf); + + ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2); + if (ret != 2) { + seq_printf(m, "faux/mst read failed\n"); + goto out; + } + seq_printf(m, "faux/mst: %*ph\n", 2, buf); + + ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1); + if (ret != 1) { + seq_printf(m, "mst ctrl read failed\n"); + goto out; + } + seq_printf(m, "mst ctrl: %*ph\n", 1, buf); + + /* dump the standard OUI branch header */ + ret = drm_dp_dpcd_read(mgr->aux, DP_BRANCH_OUI, buf, DP_BRANCH_OUI_HEADER_SIZE); + if (ret != DP_BRANCH_OUI_HEADER_SIZE) { + seq_printf(m, "branch oui read failed\n"); + goto out; + } + seq_printf(m, "branch oui: %*phN devid: ", 3, buf); + + for (i = 0x3; i < 0x8 && buf[i]; i++) + seq_printf(m, "%c", buf[i]); + seq_printf(m, " revision: hw: %x.%x sw: %x.%x\n", + buf[0x9] >> 4, buf[0x9] & 0xf, buf[0xa], buf[0xb]); + if (dump_dp_payload_table(mgr, buf)) + seq_printf(m, "payload table: %*ph\n", DP_PAYLOAD_TABLE_SIZE, buf); + } + +out: + mutex_unlock(&mgr->lock); + drm_modeset_unlock(&mgr->base.lock); +} +EXPORT_SYMBOL(drm_dp_mst_dump_topology); + +static void drm_dp_tx_work(struct work_struct *work) +{ + struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work); + + mutex_lock(&mgr->qlock); + if (!list_empty(&mgr->tx_msg_downq)) + process_single_down_tx_qlock(mgr); + mutex_unlock(&mgr->qlock); +} + +static inline void +drm_dp_delayed_destroy_port(struct drm_dp_mst_port *port) +{ + drm_dp_port_set_pdt(port, DP_PEER_DEVICE_NONE, port->mcs); + + if (port->connector) { + drm_connector_unregister(port->connector); + drm_connector_put(port->connector); + } + + drm_dp_mst_put_port_malloc(port); +} + +static inline void +drm_dp_delayed_destroy_mstb(struct drm_dp_mst_branch *mstb) +{ + struct drm_dp_mst_topology_mgr *mgr = mstb->mgr; + struct drm_dp_mst_port *port, *port_tmp; + struct drm_dp_sideband_msg_tx *txmsg, *txmsg_tmp; + bool wake_tx = false; + + mutex_lock(&mgr->lock); + list_for_each_entry_safe(port, port_tmp, &mstb->ports, next) { + list_del(&port->next); + drm_dp_mst_topology_put_port(port); + } + mutex_unlock(&mgr->lock); + + /* drop any tx slot msg */ + mutex_lock(&mstb->mgr->qlock); + list_for_each_entry_safe(txmsg, txmsg_tmp, &mgr->tx_msg_downq, next) { + if (txmsg->dst != mstb) + continue; + + txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT; + list_del(&txmsg->next); + wake_tx = true; + } + mutex_unlock(&mstb->mgr->qlock); + + if (wake_tx) + wake_up_all(&mstb->mgr->tx_waitq); + + drm_dp_mst_put_mstb_malloc(mstb); +} + +static void drm_dp_delayed_destroy_work(struct work_struct *work) +{ + struct drm_dp_mst_topology_mgr *mgr = + container_of(work, struct drm_dp_mst_topology_mgr, + delayed_destroy_work); + bool send_hotplug = false, go_again; + + /* + * Not a regular list traverse as we have to drop the destroy + * connector lock before destroying the mstb/port, to avoid AB->BA + * ordering between this lock and the config mutex. + */ + do { + go_again = false; + + for (;;) { + struct drm_dp_mst_branch *mstb; + + mutex_lock(&mgr->delayed_destroy_lock); + mstb = list_first_entry_or_null(&mgr->destroy_branch_device_list, + struct drm_dp_mst_branch, + destroy_next); + if (mstb) + list_del(&mstb->destroy_next); + mutex_unlock(&mgr->delayed_destroy_lock); + + if (!mstb) + break; + + drm_dp_delayed_destroy_mstb(mstb); + go_again = true; + } + + for (;;) { + struct drm_dp_mst_port *port; + + mutex_lock(&mgr->delayed_destroy_lock); + port = list_first_entry_or_null(&mgr->destroy_port_list, + struct drm_dp_mst_port, + next); + if (port) + list_del(&port->next); + mutex_unlock(&mgr->delayed_destroy_lock); + + if (!port) + break; + + drm_dp_delayed_destroy_port(port); + send_hotplug = true; + go_again = true; + } + } while (go_again); + + if (send_hotplug) + drm_kms_helper_hotplug_event(mgr->dev); +} + +static struct drm_private_state * +drm_dp_mst_duplicate_state(struct drm_private_obj *obj) +{ + struct drm_dp_mst_topology_state *state, *old_state = + to_dp_mst_topology_state(obj->state); + struct drm_dp_mst_atomic_payload *pos, *payload; + + state = kmemdup(old_state, sizeof(*state), GFP_KERNEL); + if (!state) + return NULL; + + __drm_atomic_helper_private_obj_duplicate_state(obj, &state->base); + + INIT_LIST_HEAD(&state->payloads); + state->commit_deps = NULL; + state->num_commit_deps = 0; + state->pending_crtc_mask = 0; + + list_for_each_entry(pos, &old_state->payloads, next) { + /* Prune leftover freed timeslot allocations */ + if (pos->delete) + continue; + + payload = kmemdup(pos, sizeof(*payload), GFP_KERNEL); + if (!payload) + goto fail; + + drm_dp_mst_get_port_malloc(payload->port); + list_add(&payload->next, &state->payloads); + } + + return &state->base; + +fail: + list_for_each_entry_safe(pos, payload, &state->payloads, next) { + drm_dp_mst_put_port_malloc(pos->port); + kfree(pos); + } + kfree(state); + + return NULL; +} + +static void drm_dp_mst_destroy_state(struct drm_private_obj *obj, + struct drm_private_state *state) +{ + struct drm_dp_mst_topology_state *mst_state = + to_dp_mst_topology_state(state); + struct drm_dp_mst_atomic_payload *pos, *tmp; + int i; + + list_for_each_entry_safe(pos, tmp, &mst_state->payloads, next) { + /* We only keep references to ports with active payloads */ + if (!pos->delete) + drm_dp_mst_put_port_malloc(pos->port); + kfree(pos); + } + + for (i = 0; i < mst_state->num_commit_deps; i++) + drm_crtc_commit_put(mst_state->commit_deps[i]); + + kfree(mst_state->commit_deps); + kfree(mst_state); +} + +static bool drm_dp_mst_port_downstream_of_branch(struct drm_dp_mst_port *port, + struct drm_dp_mst_branch *branch) +{ + while (port->parent) { + if (port->parent == branch) + return true; + + if (port->parent->port_parent) + port = port->parent->port_parent; + else + break; + } + return false; +} + +static int +drm_dp_mst_atomic_check_port_bw_limit(struct drm_dp_mst_port *port, + struct drm_dp_mst_topology_state *state); + +static int +drm_dp_mst_atomic_check_mstb_bw_limit(struct drm_dp_mst_branch *mstb, + struct drm_dp_mst_topology_state *state) +{ + struct drm_dp_mst_atomic_payload *payload; + struct drm_dp_mst_port *port; + int pbn_used = 0, ret; + bool found = false; + + /* Check that we have at least one port in our state that's downstream + * of this branch, otherwise we can skip this branch + */ + list_for_each_entry(payload, &state->payloads, next) { + if (!payload->pbn || + !drm_dp_mst_port_downstream_of_branch(payload->port, mstb)) + continue; + + found = true; + break; + } + if (!found) + return 0; + + if (mstb->port_parent) + drm_dbg_atomic(mstb->mgr->dev, + "[MSTB:%p] [MST PORT:%p] Checking bandwidth limits on [MSTB:%p]\n", + mstb->port_parent->parent, mstb->port_parent, mstb); + else + drm_dbg_atomic(mstb->mgr->dev, "[MSTB:%p] Checking bandwidth limits\n", mstb); + + list_for_each_entry(port, &mstb->ports, next) { + ret = drm_dp_mst_atomic_check_port_bw_limit(port, state); + if (ret < 0) + return ret; + + pbn_used += ret; + } + + return pbn_used; +} + +static int +drm_dp_mst_atomic_check_port_bw_limit(struct drm_dp_mst_port *port, + struct drm_dp_mst_topology_state *state) +{ + struct drm_dp_mst_atomic_payload *payload; + int pbn_used = 0; + + if (port->pdt == DP_PEER_DEVICE_NONE) + return 0; + + if (drm_dp_mst_is_end_device(port->pdt, port->mcs)) { + payload = drm_atomic_get_mst_payload_state(state, port); + if (!payload) + return 0; + + /* + * This could happen if the sink deasserted its HPD line, but + * the branch device still reports it as attached (PDT != NONE). + */ + if (!port->full_pbn) { + drm_dbg_atomic(port->mgr->dev, + "[MSTB:%p] [MST PORT:%p] no BW available for the port\n", + port->parent, port); + return -EINVAL; + } + + pbn_used = payload->pbn; + } else { + pbn_used = drm_dp_mst_atomic_check_mstb_bw_limit(port->mstb, + state); + if (pbn_used <= 0) + return pbn_used; + } + + if (pbn_used > port->full_pbn) { + drm_dbg_atomic(port->mgr->dev, + "[MSTB:%p] [MST PORT:%p] required PBN of %d exceeds port limit of %d\n", + port->parent, port, pbn_used, port->full_pbn); + return -ENOSPC; + } + + drm_dbg_atomic(port->mgr->dev, "[MSTB:%p] [MST PORT:%p] uses %d out of %d PBN\n", + port->parent, port, pbn_used, port->full_pbn); + + return pbn_used; +} + +static inline int +drm_dp_mst_atomic_check_payload_alloc_limits(struct drm_dp_mst_topology_mgr *mgr, + struct drm_dp_mst_topology_state *mst_state) +{ + struct drm_dp_mst_atomic_payload *payload; + int avail_slots = mst_state->total_avail_slots, payload_count = 0; + + list_for_each_entry(payload, &mst_state->payloads, next) { + /* Releasing payloads is always OK-even if the port is gone */ + if (payload->delete) { + drm_dbg_atomic(mgr->dev, "[MST PORT:%p] releases all time slots\n", + payload->port); + continue; + } + + drm_dbg_atomic(mgr->dev, "[MST PORT:%p] requires %d time slots\n", + payload->port, payload->time_slots); + + avail_slots -= payload->time_slots; + if (avail_slots < 0) { + drm_dbg_atomic(mgr->dev, + "[MST PORT:%p] not enough time slots in mst state %p (avail=%d)\n", + payload->port, mst_state, avail_slots + payload->time_slots); + return -ENOSPC; + } + + if (++payload_count > mgr->max_payloads) { + drm_dbg_atomic(mgr->dev, + "[MST MGR:%p] state %p has too many payloads (max=%d)\n", + mgr, mst_state, mgr->max_payloads); + return -EINVAL; + } + + /* Assign a VCPI */ + if (!payload->vcpi) { + payload->vcpi = ffz(mst_state->payload_mask) + 1; + drm_dbg_atomic(mgr->dev, "[MST PORT:%p] assigned VCPI #%d\n", + payload->port, payload->vcpi); + mst_state->payload_mask |= BIT(payload->vcpi - 1); + } + } + + if (!payload_count) + mst_state->pbn_div = 0; + + drm_dbg_atomic(mgr->dev, "[MST MGR:%p] mst state %p TU pbn_div=%d avail=%d used=%d\n", + mgr, mst_state, mst_state->pbn_div, avail_slots, + mst_state->total_avail_slots - avail_slots); + + return 0; +} + +/** + * drm_dp_mst_add_affected_dsc_crtcs + * @state: Pointer to the new struct drm_dp_mst_topology_state + * @mgr: MST topology manager + * + * Whenever there is a change in mst topology + * DSC configuration would have to be recalculated + * therefore we need to trigger modeset on all affected + * CRTCs in that topology + * + * See also: + * drm_dp_mst_atomic_enable_dsc() + */ +int drm_dp_mst_add_affected_dsc_crtcs(struct drm_atomic_state *state, struct drm_dp_mst_topology_mgr *mgr) +{ + struct drm_dp_mst_topology_state *mst_state; + struct drm_dp_mst_atomic_payload *pos; + struct drm_connector *connector; + struct drm_connector_state *conn_state; + struct drm_crtc *crtc; + struct drm_crtc_state *crtc_state; + + mst_state = drm_atomic_get_mst_topology_state(state, mgr); + + if (IS_ERR(mst_state)) + return PTR_ERR(mst_state); + + list_for_each_entry(pos, &mst_state->payloads, next) { + + connector = pos->port->connector; + + if (!connector) + return -EINVAL; + + conn_state = drm_atomic_get_connector_state(state, connector); + + if (IS_ERR(conn_state)) + return PTR_ERR(conn_state); + + crtc = conn_state->crtc; + + if (!crtc) + continue; + + if (!drm_dp_mst_dsc_aux_for_port(pos->port)) + continue; + + crtc_state = drm_atomic_get_crtc_state(mst_state->base.state, crtc); + + if (IS_ERR(crtc_state)) + return PTR_ERR(crtc_state); + + drm_dbg_atomic(mgr->dev, "[MST MGR:%p] Setting mode_changed flag on CRTC %p\n", + mgr, crtc); + + crtc_state->mode_changed = true; + } + return 0; +} +EXPORT_SYMBOL(drm_dp_mst_add_affected_dsc_crtcs); + +/** + * drm_dp_mst_atomic_enable_dsc - Set DSC Enable Flag to On/Off + * @state: Pointer to the new drm_atomic_state + * @port: Pointer to the affected MST Port + * @pbn: Newly recalculated bw required for link with DSC enabled + * @enable: Boolean flag to enable or disable DSC on the port + * + * This function enables DSC on the given Port + * by recalculating its vcpi from pbn provided + * and sets dsc_enable flag to keep track of which + * ports have DSC enabled + * + */ +int drm_dp_mst_atomic_enable_dsc(struct drm_atomic_state *state, + struct drm_dp_mst_port *port, + int pbn, bool enable) +{ + struct drm_dp_mst_topology_state *mst_state; + struct drm_dp_mst_atomic_payload *payload; + int time_slots = 0; + + mst_state = drm_atomic_get_mst_topology_state(state, port->mgr); + if (IS_ERR(mst_state)) + return PTR_ERR(mst_state); + + payload = drm_atomic_get_mst_payload_state(mst_state, port); + if (!payload) { + drm_dbg_atomic(state->dev, + "[MST PORT:%p] Couldn't find payload in mst state %p\n", + port, mst_state); + return -EINVAL; + } + + if (payload->dsc_enabled == enable) { + drm_dbg_atomic(state->dev, + "[MST PORT:%p] DSC flag is already set to %d, returning %d time slots\n", + port, enable, payload->time_slots); + time_slots = payload->time_slots; + } + + if (enable) { + time_slots = drm_dp_atomic_find_time_slots(state, port->mgr, port, pbn); + drm_dbg_atomic(state->dev, + "[MST PORT:%p] Enabling DSC flag, reallocating %d time slots on the port\n", + port, time_slots); + if (time_slots < 0) + return -EINVAL; + } + + payload->dsc_enabled = enable; + + return time_slots; +} +EXPORT_SYMBOL(drm_dp_mst_atomic_enable_dsc); + +/** + * drm_dp_mst_atomic_check - Check that the new state of an MST topology in an + * atomic update is valid + * @state: Pointer to the new &struct drm_dp_mst_topology_state + * + * Checks the given topology state for an atomic update to ensure that it's + * valid. This includes checking whether there's enough bandwidth to support + * the new timeslot allocations in the atomic update. + * + * Any atomic drivers supporting DP MST must make sure to call this after + * checking the rest of their state in their + * &drm_mode_config_funcs.atomic_check() callback. + * + * See also: + * drm_dp_atomic_find_time_slots() + * drm_dp_atomic_release_time_slots() + * + * Returns: + * + * 0 if the new state is valid, negative error code otherwise. + */ +int drm_dp_mst_atomic_check(struct drm_atomic_state *state) +{ + struct drm_dp_mst_topology_mgr *mgr; + struct drm_dp_mst_topology_state *mst_state; + int i, ret = 0; + + for_each_new_mst_mgr_in_state(state, mgr, mst_state, i) { + if (!mgr->mst_state) + continue; + + ret = drm_dp_mst_atomic_check_payload_alloc_limits(mgr, mst_state); + if (ret) + break; + + mutex_lock(&mgr->lock); + ret = drm_dp_mst_atomic_check_mstb_bw_limit(mgr->mst_primary, + mst_state); + mutex_unlock(&mgr->lock); + if (ret < 0) + break; + else + ret = 0; + } + + return ret; +} +EXPORT_SYMBOL(drm_dp_mst_atomic_check); + +const struct drm_private_state_funcs drm_dp_mst_topology_state_funcs = { + .atomic_duplicate_state = drm_dp_mst_duplicate_state, + .atomic_destroy_state = drm_dp_mst_destroy_state, +}; +EXPORT_SYMBOL(drm_dp_mst_topology_state_funcs); + +/** + * drm_atomic_get_mst_topology_state: get MST topology state + * @state: global atomic state + * @mgr: MST topology manager, also the private object in this case + * + * This function wraps drm_atomic_get_priv_obj_state() passing in the MST atomic + * state vtable so that the private object state returned is that of a MST + * topology object. + * + * RETURNS: + * + * The MST topology state or error pointer. + */ +struct drm_dp_mst_topology_state *drm_atomic_get_mst_topology_state(struct drm_atomic_state *state, + struct drm_dp_mst_topology_mgr *mgr) +{ + return to_dp_mst_topology_state(drm_atomic_get_private_obj_state(state, &mgr->base)); +} +EXPORT_SYMBOL(drm_atomic_get_mst_topology_state); + +/** + * drm_atomic_get_old_mst_topology_state: get old MST topology state in atomic state, if any + * @state: global atomic state + * @mgr: MST topology manager, also the private object in this case + * + * This function wraps drm_atomic_get_old_private_obj_state() passing in the MST atomic + * state vtable so that the private object state returned is that of a MST + * topology object. + * + * Returns: + * + * The old MST topology state, or NULL if there's no topology state for this MST mgr + * in the global atomic state + */ +struct drm_dp_mst_topology_state * +drm_atomic_get_old_mst_topology_state(struct drm_atomic_state *state, + struct drm_dp_mst_topology_mgr *mgr) +{ + struct drm_private_state *old_priv_state = + drm_atomic_get_old_private_obj_state(state, &mgr->base); + + return old_priv_state ? to_dp_mst_topology_state(old_priv_state) : NULL; +} +EXPORT_SYMBOL(drm_atomic_get_old_mst_topology_state); + +/** + * drm_atomic_get_new_mst_topology_state: get new MST topology state in atomic state, if any + * @state: global atomic state + * @mgr: MST topology manager, also the private object in this case + * + * This function wraps drm_atomic_get_new_private_obj_state() passing in the MST atomic + * state vtable so that the private object state returned is that of a MST + * topology object. + * + * Returns: + * + * The new MST topology state, or NULL if there's no topology state for this MST mgr + * in the global atomic state + */ +struct drm_dp_mst_topology_state * +drm_atomic_get_new_mst_topology_state(struct drm_atomic_state *state, + struct drm_dp_mst_topology_mgr *mgr) +{ + struct drm_private_state *new_priv_state = + drm_atomic_get_new_private_obj_state(state, &mgr->base); + + return new_priv_state ? to_dp_mst_topology_state(new_priv_state) : NULL; +} +EXPORT_SYMBOL(drm_atomic_get_new_mst_topology_state); + +/** + * drm_dp_mst_topology_mgr_init - initialise a topology manager + * @mgr: manager struct to initialise + * @dev: device providing this structure - for i2c addition. + * @aux: DP helper aux channel to talk to this device + * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit + * @max_payloads: maximum number of payloads this GPU can source + * @conn_base_id: the connector object ID the MST device is connected to. + * + * Return 0 for success, or negative error code on failure + */ +int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr, + struct drm_device *dev, struct drm_dp_aux *aux, + int max_dpcd_transaction_bytes, int max_payloads, + int conn_base_id) +{ + struct drm_dp_mst_topology_state *mst_state; + + mutex_init(&mgr->lock); + mutex_init(&mgr->qlock); + mutex_init(&mgr->delayed_destroy_lock); + mutex_init(&mgr->up_req_lock); + mutex_init(&mgr->probe_lock); +#if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS) + mutex_init(&mgr->topology_ref_history_lock); + stack_depot_init(); +#endif + INIT_LIST_HEAD(&mgr->tx_msg_downq); + INIT_LIST_HEAD(&mgr->destroy_port_list); + INIT_LIST_HEAD(&mgr->destroy_branch_device_list); + INIT_LIST_HEAD(&mgr->up_req_list); + + /* + * delayed_destroy_work will be queued on a dedicated WQ, so that any + * requeuing will be also flushed when deiniting the topology manager. + */ + mgr->delayed_destroy_wq = alloc_ordered_workqueue("drm_dp_mst_wq", 0); + if (mgr->delayed_destroy_wq == NULL) + return -ENOMEM; + + INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work); + INIT_WORK(&mgr->tx_work, drm_dp_tx_work); + INIT_WORK(&mgr->delayed_destroy_work, drm_dp_delayed_destroy_work); + INIT_WORK(&mgr->up_req_work, drm_dp_mst_up_req_work); + init_waitqueue_head(&mgr->tx_waitq); + mgr->dev = dev; + mgr->aux = aux; + mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes; + mgr->max_payloads = max_payloads; + mgr->conn_base_id = conn_base_id; + + mst_state = kzalloc(sizeof(*mst_state), GFP_KERNEL); + if (mst_state == NULL) + return -ENOMEM; + + mst_state->total_avail_slots = 63; + mst_state->start_slot = 1; + + mst_state->mgr = mgr; + INIT_LIST_HEAD(&mst_state->payloads); + + drm_atomic_private_obj_init(dev, &mgr->base, + &mst_state->base, + &drm_dp_mst_topology_state_funcs); + + return 0; +} +EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init); + +/** + * drm_dp_mst_topology_mgr_destroy() - destroy topology manager. + * @mgr: manager to destroy + */ +void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr) +{ + drm_dp_mst_topology_mgr_set_mst(mgr, false); + flush_work(&mgr->work); + /* The following will also drain any requeued work on the WQ. */ + if (mgr->delayed_destroy_wq) { + destroy_workqueue(mgr->delayed_destroy_wq); + mgr->delayed_destroy_wq = NULL; + } + mgr->dev = NULL; + mgr->aux = NULL; + drm_atomic_private_obj_fini(&mgr->base); + mgr->funcs = NULL; + + mutex_destroy(&mgr->delayed_destroy_lock); + mutex_destroy(&mgr->qlock); + mutex_destroy(&mgr->lock); + mutex_destroy(&mgr->up_req_lock); + mutex_destroy(&mgr->probe_lock); +#if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS) + mutex_destroy(&mgr->topology_ref_history_lock); +#endif +} +EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy); + +static bool remote_i2c_read_ok(const struct i2c_msg msgs[], int num) +{ + int i; + + if (num - 1 > DP_REMOTE_I2C_READ_MAX_TRANSACTIONS) + return false; + + for (i = 0; i < num - 1; i++) { + if (msgs[i].flags & I2C_M_RD || + msgs[i].len > 0xff) + return false; + } + + return msgs[num - 1].flags & I2C_M_RD && + msgs[num - 1].len <= 0xff; +} + +static bool remote_i2c_write_ok(const struct i2c_msg msgs[], int num) +{ + int i; + + for (i = 0; i < num - 1; i++) { + if (msgs[i].flags & I2C_M_RD || !(msgs[i].flags & I2C_M_STOP) || + msgs[i].len > 0xff) + return false; + } + + return !(msgs[num - 1].flags & I2C_M_RD) && msgs[num - 1].len <= 0xff; +} + +static int drm_dp_mst_i2c_read(struct drm_dp_mst_branch *mstb, + struct drm_dp_mst_port *port, + struct i2c_msg *msgs, int num) +{ + struct drm_dp_mst_topology_mgr *mgr = port->mgr; + unsigned int i; + struct drm_dp_sideband_msg_req_body msg; + struct drm_dp_sideband_msg_tx *txmsg = NULL; + int ret; + + memset(&msg, 0, sizeof(msg)); + msg.req_type = DP_REMOTE_I2C_READ; + msg.u.i2c_read.num_transactions = num - 1; + msg.u.i2c_read.port_number = port->port_num; + for (i = 0; i < num - 1; i++) { + msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr; + msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len; + msg.u.i2c_read.transactions[i].bytes = msgs[i].buf; + msg.u.i2c_read.transactions[i].no_stop_bit = !(msgs[i].flags & I2C_M_STOP); + } + msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr; + msg.u.i2c_read.num_bytes_read = msgs[num - 1].len; + + txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); + if (!txmsg) { + ret = -ENOMEM; + goto out; + } + + txmsg->dst = mstb; + drm_dp_encode_sideband_req(&msg, txmsg); + + drm_dp_queue_down_tx(mgr, txmsg); + + ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); + if (ret > 0) { + + if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) { + ret = -EREMOTEIO; + goto out; + } + if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) { + ret = -EIO; + goto out; + } + memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len); + ret = num; + } +out: + kfree(txmsg); + return ret; +} + +static int drm_dp_mst_i2c_write(struct drm_dp_mst_branch *mstb, + struct drm_dp_mst_port *port, + struct i2c_msg *msgs, int num) +{ + struct drm_dp_mst_topology_mgr *mgr = port->mgr; + unsigned int i; + struct drm_dp_sideband_msg_req_body msg; + struct drm_dp_sideband_msg_tx *txmsg = NULL; + int ret; + + txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); + if (!txmsg) { + ret = -ENOMEM; + goto out; + } + for (i = 0; i < num; i++) { + memset(&msg, 0, sizeof(msg)); + msg.req_type = DP_REMOTE_I2C_WRITE; + msg.u.i2c_write.port_number = port->port_num; + msg.u.i2c_write.write_i2c_device_id = msgs[i].addr; + msg.u.i2c_write.num_bytes = msgs[i].len; + msg.u.i2c_write.bytes = msgs[i].buf; + + memset(txmsg, 0, sizeof(*txmsg)); + txmsg->dst = mstb; + + drm_dp_encode_sideband_req(&msg, txmsg); + drm_dp_queue_down_tx(mgr, txmsg); + + ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); + if (ret > 0) { + if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) { + ret = -EREMOTEIO; + goto out; + } + } else { + goto out; + } + } + ret = num; +out: + kfree(txmsg); + return ret; +} + +/* I2C device */ +static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, + struct i2c_msg *msgs, int num) +{ + struct drm_dp_aux *aux = adapter->algo_data; + struct drm_dp_mst_port *port = + container_of(aux, struct drm_dp_mst_port, aux); + struct drm_dp_mst_branch *mstb; + struct drm_dp_mst_topology_mgr *mgr = port->mgr; + int ret; + + mstb = drm_dp_mst_topology_get_mstb_validated(mgr, port->parent); + if (!mstb) + return -EREMOTEIO; + + if (remote_i2c_read_ok(msgs, num)) { + ret = drm_dp_mst_i2c_read(mstb, port, msgs, num); + } else if (remote_i2c_write_ok(msgs, num)) { + ret = drm_dp_mst_i2c_write(mstb, port, msgs, num); + } else { + drm_dbg_kms(mgr->dev, "Unsupported I2C transaction for MST device\n"); + ret = -EIO; + } + + drm_dp_mst_topology_put_mstb(mstb); + return ret; +} + +static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | + I2C_FUNC_SMBUS_READ_BLOCK_DATA | + I2C_FUNC_SMBUS_BLOCK_PROC_CALL | + I2C_FUNC_10BIT_ADDR; +} + +static const struct i2c_algorithm drm_dp_mst_i2c_algo = { + .functionality = drm_dp_mst_i2c_functionality, + .master_xfer = drm_dp_mst_i2c_xfer, +}; + +/** + * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX + * @port: The port to add the I2C bus on + * + * Returns 0 on success or a negative error code on failure. + */ +static int drm_dp_mst_register_i2c_bus(struct drm_dp_mst_port *port) +{ + struct drm_dp_aux *aux = &port->aux; + struct device *parent_dev = port->mgr->dev->dev; + + aux->ddc.algo = &drm_dp_mst_i2c_algo; + aux->ddc.algo_data = aux; + aux->ddc.retries = 3; + + aux->ddc.class = I2C_CLASS_DDC; + aux->ddc.owner = THIS_MODULE; + /* FIXME: set the kdev of the port's connector as parent */ + aux->ddc.dev.parent = parent_dev; + aux->ddc.dev.of_node = parent_dev->of_node; + + strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(parent_dev), + sizeof(aux->ddc.name)); + + return i2c_add_adapter(&aux->ddc); +} + +/** + * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter + * @port: The port to remove the I2C bus from + */ +static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_mst_port *port) +{ + i2c_del_adapter(&port->aux.ddc); +} + +/** + * drm_dp_mst_is_virtual_dpcd() - Is the given port a virtual DP Peer Device + * @port: The port to check + * + * A single physical MST hub object can be represented in the topology + * by multiple branches, with virtual ports between those branches. + * + * As of DP1.4, An MST hub with internal (virtual) ports must expose + * certain DPCD registers over those ports. See sections 2.6.1.1.1 + * and 2.6.1.1.2 of Display Port specification v1.4 for details. + * + * May acquire mgr->lock + * + * Returns: + * true if the port is a virtual DP peer device, false otherwise + */ +static bool drm_dp_mst_is_virtual_dpcd(struct drm_dp_mst_port *port) +{ + struct drm_dp_mst_port *downstream_port; + + if (!port || port->dpcd_rev < DP_DPCD_REV_14) + return false; + + /* Virtual DP Sink (Internal Display Panel) */ + if (port->port_num >= 8) + return true; + + /* DP-to-HDMI Protocol Converter */ + if (port->pdt == DP_PEER_DEVICE_DP_LEGACY_CONV && + !port->mcs && + port->ldps) + return true; + + /* DP-to-DP */ + mutex_lock(&port->mgr->lock); + if (port->pdt == DP_PEER_DEVICE_MST_BRANCHING && + port->mstb && + port->mstb->num_ports == 2) { + list_for_each_entry(downstream_port, &port->mstb->ports, next) { + if (downstream_port->pdt == DP_PEER_DEVICE_SST_SINK && + !downstream_port->input) { + mutex_unlock(&port->mgr->lock); + return true; + } + } + } + mutex_unlock(&port->mgr->lock); + + return false; +} + +/** + * drm_dp_mst_dsc_aux_for_port() - Find the correct aux for DSC + * @port: The port to check. A leaf of the MST tree with an attached display. + * + * Depending on the situation, DSC may be enabled via the endpoint aux, + * the immediately upstream aux, or the connector's physical aux. + * + * This is both the correct aux to read DSC_CAPABILITY and the + * correct aux to write DSC_ENABLED. + * + * This operation can be expensive (up to four aux reads), so + * the caller should cache the return. + * + * Returns: + * NULL if DSC cannot be enabled on this port, otherwise the aux device + */ +struct drm_dp_aux *drm_dp_mst_dsc_aux_for_port(struct drm_dp_mst_port *port) +{ + struct drm_dp_mst_port *immediate_upstream_port; + struct drm_dp_mst_port *fec_port; + struct drm_dp_desc desc = {}; + u8 endpoint_fec; + u8 endpoint_dsc; + + if (!port) + return NULL; + + if (port->parent->port_parent) + immediate_upstream_port = port->parent->port_parent; + else + immediate_upstream_port = NULL; + + fec_port = immediate_upstream_port; + while (fec_port) { + /* + * Each physical link (i.e. not a virtual port) between the + * output and the primary device must support FEC + */ + if (!drm_dp_mst_is_virtual_dpcd(fec_port) && + !fec_port->fec_capable) + return NULL; + + fec_port = fec_port->parent->port_parent; + } + + /* DP-to-DP peer device */ + if (drm_dp_mst_is_virtual_dpcd(immediate_upstream_port)) { + u8 upstream_dsc; + + if (drm_dp_dpcd_read(&port->aux, + DP_DSC_SUPPORT, &endpoint_dsc, 1) != 1) + return NULL; + if (drm_dp_dpcd_read(&port->aux, + DP_FEC_CAPABILITY, &endpoint_fec, 1) != 1) + return NULL; + if (drm_dp_dpcd_read(&immediate_upstream_port->aux, + DP_DSC_SUPPORT, &upstream_dsc, 1) != 1) + return NULL; + + /* Enpoint decompression with DP-to-DP peer device */ + if ((endpoint_dsc & DP_DSC_DECOMPRESSION_IS_SUPPORTED) && + (endpoint_fec & DP_FEC_CAPABLE) && + (upstream_dsc & DP_DSC_PASSTHROUGH_IS_SUPPORTED)) { + port->passthrough_aux = &immediate_upstream_port->aux; + return &port->aux; + } + + /* Virtual DPCD decompression with DP-to-DP peer device */ + return &immediate_upstream_port->aux; + } + + /* Virtual DPCD decompression with DP-to-HDMI or Virtual DP Sink */ + if (drm_dp_mst_is_virtual_dpcd(port)) + return &port->aux; + + /* + * Synaptics quirk + * Applies to ports for which: + * - Physical aux has Synaptics OUI + * - DPv1.4 or higher + * - Port is on primary branch device + * - Not a VGA adapter (DP_DWN_STRM_PORT_TYPE_ANALOG) + */ + if (drm_dp_read_desc(port->mgr->aux, &desc, true)) + return NULL; + + if (drm_dp_has_quirk(&desc, DP_DPCD_QUIRK_DSC_WITHOUT_VIRTUAL_DPCD) && + port->mgr->dpcd[DP_DPCD_REV] >= DP_DPCD_REV_14 && + port->parent == port->mgr->mst_primary) { + u8 dpcd_ext[DP_RECEIVER_CAP_SIZE]; + + if (drm_dp_read_dpcd_caps(port->mgr->aux, dpcd_ext) < 0) + return NULL; + + if ((dpcd_ext[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_PRESENT) && + ((dpcd_ext[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_TYPE_MASK) + != DP_DWN_STRM_PORT_TYPE_ANALOG)) + return port->mgr->aux; + } + + /* + * The check below verifies if the MST sink + * connected to the GPU is capable of DSC - + * therefore the endpoint needs to be + * both DSC and FEC capable. + */ + if (drm_dp_dpcd_read(&port->aux, + DP_DSC_SUPPORT, &endpoint_dsc, 1) != 1) + return NULL; + if (drm_dp_dpcd_read(&port->aux, + DP_FEC_CAPABILITY, &endpoint_fec, 1) != 1) + return NULL; + if ((endpoint_dsc & DP_DSC_DECOMPRESSION_IS_SUPPORTED) && + (endpoint_fec & DP_FEC_CAPABLE)) + return &port->aux; + + return NULL; +} +EXPORT_SYMBOL(drm_dp_mst_dsc_aux_for_port); diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology_internal.h b/drivers/gpu/drm/display/drm_dp_mst_topology_internal.h new file mode 100644 index 000000000..a785ccbfd --- /dev/null +++ b/drivers/gpu/drm/display/drm_dp_mst_topology_internal.h @@ -0,0 +1,24 @@ +/* SPDX-License-Identifier: GPL-2.0-only + * + * Declarations for DP MST related functions which are only used in selftests + * + * Copyright © 2018 Red Hat + * Authors: + * Lyude Paul <lyude@redhat.com> + */ + +#ifndef _DRM_DP_MST_HELPER_INTERNAL_H_ +#define _DRM_DP_MST_HELPER_INTERNAL_H_ + +#include <drm/display/drm_dp_mst_helper.h> + +void +drm_dp_encode_sideband_req(const struct drm_dp_sideband_msg_req_body *req, + struct drm_dp_sideband_msg_tx *raw); +int drm_dp_decode_sideband_req(const struct drm_dp_sideband_msg_tx *raw, + struct drm_dp_sideband_msg_req_body *req); +void +drm_dp_dump_sideband_msg_req_body(const struct drm_dp_sideband_msg_req_body *req, + int indent, struct drm_printer *printer); + +#endif /* !_DRM_DP_MST_HELPER_INTERNAL_H_ */ diff --git a/drivers/gpu/drm/display/drm_dsc_helper.c b/drivers/gpu/drm/display/drm_dsc_helper.c new file mode 100644 index 000000000..c869c6e51 --- /dev/null +++ b/drivers/gpu/drm/display/drm_dsc_helper.c @@ -0,0 +1,409 @@ +// SPDX-License-Identifier: MIT +/* + * Copyright © 2018 Intel Corp + * + * Author: + * Manasi Navare <manasi.d.navare@intel.com> + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/errno.h> +#include <linux/byteorder/generic.h> + +#include <drm/display/drm_dp_helper.h> +#include <drm/display/drm_dsc_helper.h> +#include <drm/drm_print.h> + +/** + * DOC: dsc helpers + * + * VESA specification for DP 1.4 adds a new feature called Display Stream + * Compression (DSC) used to compress the pixel bits before sending it on + * DP/eDP/MIPI DSI interface. DSC is required to be enabled so that the existing + * display interfaces can support high resolutions at higher frames rates uisng + * the maximum available link capacity of these interfaces. + * + * These functions contain some common logic and helpers to deal with VESA + * Display Stream Compression standard required for DSC on Display Port/eDP or + * MIPI display interfaces. + */ + +/** + * drm_dsc_dp_pps_header_init() - Initializes the PPS Header + * for DisplayPort as per the DP 1.4 spec. + * @pps_header: Secondary data packet header for DSC Picture + * Parameter Set as defined in &struct dp_sdp_header + * + * DP 1.4 spec defines the secondary data packet for sending the + * picture parameter infoframes from the source to the sink. + * This function populates the SDP header defined in + * &struct dp_sdp_header. + */ +void drm_dsc_dp_pps_header_init(struct dp_sdp_header *pps_header) +{ + memset(pps_header, 0, sizeof(*pps_header)); + + pps_header->HB1 = DP_SDP_PPS; + pps_header->HB2 = DP_SDP_PPS_HEADER_PAYLOAD_BYTES_MINUS_1; +} +EXPORT_SYMBOL(drm_dsc_dp_pps_header_init); + +/** + * drm_dsc_dp_rc_buffer_size - get rc buffer size in bytes + * @rc_buffer_block_size: block size code, according to DPCD offset 62h + * @rc_buffer_size: number of blocks - 1, according to DPCD offset 63h + * + * return: + * buffer size in bytes, or 0 on invalid input + */ +int drm_dsc_dp_rc_buffer_size(u8 rc_buffer_block_size, u8 rc_buffer_size) +{ + int size = 1024 * (rc_buffer_size + 1); + + switch (rc_buffer_block_size) { + case DP_DSC_RC_BUF_BLK_SIZE_1: + return 1 * size; + case DP_DSC_RC_BUF_BLK_SIZE_4: + return 4 * size; + case DP_DSC_RC_BUF_BLK_SIZE_16: + return 16 * size; + case DP_DSC_RC_BUF_BLK_SIZE_64: + return 64 * size; + default: + return 0; + } +} +EXPORT_SYMBOL(drm_dsc_dp_rc_buffer_size); + +/** + * drm_dsc_pps_payload_pack() - Populates the DSC PPS + * + * @pps_payload: + * Bitwise struct for DSC Picture Parameter Set. This is defined + * by &struct drm_dsc_picture_parameter_set + * @dsc_cfg: + * DSC Configuration data filled by driver as defined by + * &struct drm_dsc_config + * + * DSC source device sends a picture parameter set (PPS) containing the + * information required by the sink to decode the compressed frame. Driver + * populates the DSC PPS struct using the DSC configuration parameters in + * the order expected by the DSC Display Sink device. For the DSC, the sink + * device expects the PPS payload in big endian format for fields + * that span more than 1 byte. + */ +void drm_dsc_pps_payload_pack(struct drm_dsc_picture_parameter_set *pps_payload, + const struct drm_dsc_config *dsc_cfg) +{ + int i; + + /* Protect against someone accidentally changing struct size */ + BUILD_BUG_ON(sizeof(*pps_payload) != + DP_SDP_PPS_HEADER_PAYLOAD_BYTES_MINUS_1 + 1); + + memset(pps_payload, 0, sizeof(*pps_payload)); + + /* PPS 0 */ + pps_payload->dsc_version = + dsc_cfg->dsc_version_minor | + dsc_cfg->dsc_version_major << DSC_PPS_VERSION_MAJOR_SHIFT; + + /* PPS 1, 2 is 0 */ + + /* PPS 3 */ + pps_payload->pps_3 = + dsc_cfg->line_buf_depth | + dsc_cfg->bits_per_component << DSC_PPS_BPC_SHIFT; + + /* PPS 4 */ + pps_payload->pps_4 = + ((dsc_cfg->bits_per_pixel & DSC_PPS_BPP_HIGH_MASK) >> + DSC_PPS_MSB_SHIFT) | + dsc_cfg->vbr_enable << DSC_PPS_VBR_EN_SHIFT | + dsc_cfg->simple_422 << DSC_PPS_SIMPLE422_SHIFT | + dsc_cfg->convert_rgb << DSC_PPS_CONVERT_RGB_SHIFT | + dsc_cfg->block_pred_enable << DSC_PPS_BLOCK_PRED_EN_SHIFT; + + /* PPS 5 */ + pps_payload->bits_per_pixel_low = + (dsc_cfg->bits_per_pixel & DSC_PPS_LSB_MASK); + + /* + * The DSC panel expects the PPS packet to have big endian format + * for data spanning 2 bytes. Use a macro cpu_to_be16() to convert + * to big endian format. If format is little endian, it will swap + * bytes to convert to Big endian else keep it unchanged. + */ + + /* PPS 6, 7 */ + pps_payload->pic_height = cpu_to_be16(dsc_cfg->pic_height); + + /* PPS 8, 9 */ + pps_payload->pic_width = cpu_to_be16(dsc_cfg->pic_width); + + /* PPS 10, 11 */ + pps_payload->slice_height = cpu_to_be16(dsc_cfg->slice_height); + + /* PPS 12, 13 */ + pps_payload->slice_width = cpu_to_be16(dsc_cfg->slice_width); + + /* PPS 14, 15 */ + pps_payload->chunk_size = cpu_to_be16(dsc_cfg->slice_chunk_size); + + /* PPS 16 */ + pps_payload->initial_xmit_delay_high = + ((dsc_cfg->initial_xmit_delay & + DSC_PPS_INIT_XMIT_DELAY_HIGH_MASK) >> + DSC_PPS_MSB_SHIFT); + + /* PPS 17 */ + pps_payload->initial_xmit_delay_low = + (dsc_cfg->initial_xmit_delay & DSC_PPS_LSB_MASK); + + /* PPS 18, 19 */ + pps_payload->initial_dec_delay = + cpu_to_be16(dsc_cfg->initial_dec_delay); + + /* PPS 20 is 0 */ + + /* PPS 21 */ + pps_payload->initial_scale_value = + dsc_cfg->initial_scale_value; + + /* PPS 22, 23 */ + pps_payload->scale_increment_interval = + cpu_to_be16(dsc_cfg->scale_increment_interval); + + /* PPS 24 */ + pps_payload->scale_decrement_interval_high = + ((dsc_cfg->scale_decrement_interval & + DSC_PPS_SCALE_DEC_INT_HIGH_MASK) >> + DSC_PPS_MSB_SHIFT); + + /* PPS 25 */ + pps_payload->scale_decrement_interval_low = + (dsc_cfg->scale_decrement_interval & DSC_PPS_LSB_MASK); + + /* PPS 26[7:0], PPS 27[7:5] RESERVED */ + + /* PPS 27 */ + pps_payload->first_line_bpg_offset = + dsc_cfg->first_line_bpg_offset; + + /* PPS 28, 29 */ + pps_payload->nfl_bpg_offset = + cpu_to_be16(dsc_cfg->nfl_bpg_offset); + + /* PPS 30, 31 */ + pps_payload->slice_bpg_offset = + cpu_to_be16(dsc_cfg->slice_bpg_offset); + + /* PPS 32, 33 */ + pps_payload->initial_offset = + cpu_to_be16(dsc_cfg->initial_offset); + + /* PPS 34, 35 */ + pps_payload->final_offset = cpu_to_be16(dsc_cfg->final_offset); + + /* PPS 36 */ + pps_payload->flatness_min_qp = dsc_cfg->flatness_min_qp; + + /* PPS 37 */ + pps_payload->flatness_max_qp = dsc_cfg->flatness_max_qp; + + /* PPS 38, 39 */ + pps_payload->rc_model_size = cpu_to_be16(dsc_cfg->rc_model_size); + + /* PPS 40 */ + pps_payload->rc_edge_factor = DSC_RC_EDGE_FACTOR_CONST; + + /* PPS 41 */ + pps_payload->rc_quant_incr_limit0 = + dsc_cfg->rc_quant_incr_limit0; + + /* PPS 42 */ + pps_payload->rc_quant_incr_limit1 = + dsc_cfg->rc_quant_incr_limit1; + + /* PPS 43 */ + pps_payload->rc_tgt_offset = DSC_RC_TGT_OFFSET_LO_CONST | + DSC_RC_TGT_OFFSET_HI_CONST << DSC_PPS_RC_TGT_OFFSET_HI_SHIFT; + + /* PPS 44 - 57 */ + for (i = 0; i < DSC_NUM_BUF_RANGES - 1; i++) + pps_payload->rc_buf_thresh[i] = + dsc_cfg->rc_buf_thresh[i]; + + /* PPS 58 - 87 */ + /* + * For DSC sink programming the RC Range parameter fields + * are as follows: Min_qp[15:11], max_qp[10:6], offset[5:0] + */ + for (i = 0; i < DSC_NUM_BUF_RANGES; i++) { + pps_payload->rc_range_parameters[i] = + cpu_to_be16((dsc_cfg->rc_range_params[i].range_min_qp << + DSC_PPS_RC_RANGE_MINQP_SHIFT) | + (dsc_cfg->rc_range_params[i].range_max_qp << + DSC_PPS_RC_RANGE_MAXQP_SHIFT) | + (dsc_cfg->rc_range_params[i].range_bpg_offset)); + } + + /* PPS 88 */ + pps_payload->native_422_420 = dsc_cfg->native_422 | + dsc_cfg->native_420 << DSC_PPS_NATIVE_420_SHIFT; + + /* PPS 89 */ + pps_payload->second_line_bpg_offset = + dsc_cfg->second_line_bpg_offset; + + /* PPS 90, 91 */ + pps_payload->nsl_bpg_offset = + cpu_to_be16(dsc_cfg->nsl_bpg_offset); + + /* PPS 92, 93 */ + pps_payload->second_line_offset_adj = + cpu_to_be16(dsc_cfg->second_line_offset_adj); + + /* PPS 94 - 127 are O */ +} +EXPORT_SYMBOL(drm_dsc_pps_payload_pack); + +/** + * drm_dsc_compute_rc_parameters() - Write rate control + * parameters to the dsc configuration defined in + * &struct drm_dsc_config in accordance with the DSC 1.2 + * specification. Some configuration fields must be present + * beforehand. + * + * @vdsc_cfg: + * DSC Configuration data partially filled by driver + */ +int drm_dsc_compute_rc_parameters(struct drm_dsc_config *vdsc_cfg) +{ + unsigned long groups_per_line = 0; + unsigned long groups_total = 0; + unsigned long num_extra_mux_bits = 0; + unsigned long slice_bits = 0; + unsigned long hrd_delay = 0; + unsigned long final_scale = 0; + unsigned long rbs_min = 0; + + if (vdsc_cfg->native_420 || vdsc_cfg->native_422) { + /* Number of groups used to code each line of a slice */ + groups_per_line = DIV_ROUND_UP(vdsc_cfg->slice_width / 2, + DSC_RC_PIXELS_PER_GROUP); + + /* chunksize in Bytes */ + vdsc_cfg->slice_chunk_size = DIV_ROUND_UP(vdsc_cfg->slice_width / 2 * + vdsc_cfg->bits_per_pixel, + (8 * 16)); + } else { + /* Number of groups used to code each line of a slice */ + groups_per_line = DIV_ROUND_UP(vdsc_cfg->slice_width, + DSC_RC_PIXELS_PER_GROUP); + + /* chunksize in Bytes */ + vdsc_cfg->slice_chunk_size = DIV_ROUND_UP(vdsc_cfg->slice_width * + vdsc_cfg->bits_per_pixel, + (8 * 16)); + } + + if (vdsc_cfg->convert_rgb) + num_extra_mux_bits = 3 * (vdsc_cfg->mux_word_size + + (4 * vdsc_cfg->bits_per_component + 4) + - 2); + else if (vdsc_cfg->native_422) + num_extra_mux_bits = 4 * vdsc_cfg->mux_word_size + + (4 * vdsc_cfg->bits_per_component + 4) + + 3 * (4 * vdsc_cfg->bits_per_component) - 2; + else + num_extra_mux_bits = 3 * vdsc_cfg->mux_word_size + + (4 * vdsc_cfg->bits_per_component + 4) + + 2 * (4 * vdsc_cfg->bits_per_component) - 2; + /* Number of bits in one Slice */ + slice_bits = 8 * vdsc_cfg->slice_chunk_size * vdsc_cfg->slice_height; + + while ((num_extra_mux_bits > 0) && + ((slice_bits - num_extra_mux_bits) % vdsc_cfg->mux_word_size)) + num_extra_mux_bits--; + + if (groups_per_line < vdsc_cfg->initial_scale_value - 8) + vdsc_cfg->initial_scale_value = groups_per_line + 8; + + /* scale_decrement_interval calculation according to DSC spec 1.11 */ + if (vdsc_cfg->initial_scale_value > 8) + vdsc_cfg->scale_decrement_interval = groups_per_line / + (vdsc_cfg->initial_scale_value - 8); + else + vdsc_cfg->scale_decrement_interval = DSC_SCALE_DECREMENT_INTERVAL_MAX; + + vdsc_cfg->final_offset = vdsc_cfg->rc_model_size - + (vdsc_cfg->initial_xmit_delay * + vdsc_cfg->bits_per_pixel + 8) / 16 + num_extra_mux_bits; + + if (vdsc_cfg->final_offset >= vdsc_cfg->rc_model_size) { + DRM_DEBUG_KMS("FinalOfs < RcModelSze for this InitialXmitDelay\n"); + return -ERANGE; + } + + final_scale = (vdsc_cfg->rc_model_size * 8) / + (vdsc_cfg->rc_model_size - vdsc_cfg->final_offset); + if (vdsc_cfg->slice_height > 1) + /* + * NflBpgOffset is 16 bit value with 11 fractional bits + * hence we multiply by 2^11 for preserving the + * fractional part + */ + vdsc_cfg->nfl_bpg_offset = DIV_ROUND_UP((vdsc_cfg->first_line_bpg_offset << 11), + (vdsc_cfg->slice_height - 1)); + else + vdsc_cfg->nfl_bpg_offset = 0; + + /* Number of groups used to code the entire slice */ + groups_total = groups_per_line * vdsc_cfg->slice_height; + + /* slice_bpg_offset is 16 bit value with 11 fractional bits */ + vdsc_cfg->slice_bpg_offset = DIV_ROUND_UP(((vdsc_cfg->rc_model_size - + vdsc_cfg->initial_offset + + num_extra_mux_bits) << 11), + groups_total); + + if (final_scale > 9) { + /* + * ScaleIncrementInterval = + * finaloffset/((NflBpgOffset + SliceBpgOffset)*8(finalscale - 1.125)) + * as (NflBpgOffset + SliceBpgOffset) has 11 bit fractional value, + * we need divide by 2^11 from pstDscCfg values + */ + vdsc_cfg->scale_increment_interval = + (vdsc_cfg->final_offset * (1 << 11)) / + ((vdsc_cfg->nfl_bpg_offset + + vdsc_cfg->slice_bpg_offset) * + (final_scale - 9)); + } else { + /* + * If finalScaleValue is less than or equal to 9, a value of 0 should + * be used to disable the scale increment at the end of the slice + */ + vdsc_cfg->scale_increment_interval = 0; + } + + /* + * DSC spec mentions that bits_per_pixel specifies the target + * bits/pixel (bpp) rate that is used by the encoder, + * in steps of 1/16 of a bit per pixel + */ + rbs_min = vdsc_cfg->rc_model_size - vdsc_cfg->initial_offset + + DIV_ROUND_UP(vdsc_cfg->initial_xmit_delay * + vdsc_cfg->bits_per_pixel, 16) + + groups_per_line * vdsc_cfg->first_line_bpg_offset; + + hrd_delay = DIV_ROUND_UP((rbs_min * 16), vdsc_cfg->bits_per_pixel); + vdsc_cfg->rc_bits = (hrd_delay * vdsc_cfg->bits_per_pixel) / 16; + vdsc_cfg->initial_dec_delay = hrd_delay - vdsc_cfg->initial_xmit_delay; + + return 0; +} +EXPORT_SYMBOL(drm_dsc_compute_rc_parameters); diff --git a/drivers/gpu/drm/display/drm_hdcp_helper.c b/drivers/gpu/drm/display/drm_hdcp_helper.c new file mode 100644 index 000000000..e78999c72 --- /dev/null +++ b/drivers/gpu/drm/display/drm_hdcp_helper.c @@ -0,0 +1,421 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Intel Corporation. + * + * Authors: + * Ramalingam C <ramalingam.c@intel.com> + */ + +#include <linux/device.h> +#include <linux/err.h> +#include <linux/gfp.h> +#include <linux/export.h> +#include <linux/slab.h> +#include <linux/firmware.h> + +#include <drm/display/drm_hdcp_helper.h> +#include <drm/drm_sysfs.h> +#include <drm/drm_print.h> +#include <drm/drm_device.h> +#include <drm/drm_property.h> +#include <drm/drm_mode_object.h> +#include <drm/drm_connector.h> + +static inline void drm_hdcp_print_ksv(const u8 *ksv) +{ + DRM_DEBUG("\t%#02x, %#02x, %#02x, %#02x, %#02x\n", + ksv[0], ksv[1], ksv[2], ksv[3], ksv[4]); +} + +static u32 drm_hdcp_get_revoked_ksv_count(const u8 *buf, u32 vrls_length) +{ + u32 parsed_bytes = 0, ksv_count = 0, vrl_ksv_cnt, vrl_sz; + + while (parsed_bytes < vrls_length) { + vrl_ksv_cnt = *buf; + ksv_count += vrl_ksv_cnt; + + vrl_sz = (vrl_ksv_cnt * DRM_HDCP_KSV_LEN) + 1; + buf += vrl_sz; + parsed_bytes += vrl_sz; + } + + /* + * When vrls are not valid, ksvs are not considered. + * Hence SRM will be discarded. + */ + if (parsed_bytes != vrls_length) + ksv_count = 0; + + return ksv_count; +} + +static u32 drm_hdcp_get_revoked_ksvs(const u8 *buf, u8 **revoked_ksv_list, + u32 vrls_length) +{ + u32 vrl_ksv_cnt, vrl_ksv_sz, vrl_idx = 0; + u32 parsed_bytes = 0, ksv_count = 0; + + do { + vrl_ksv_cnt = *buf; + vrl_ksv_sz = vrl_ksv_cnt * DRM_HDCP_KSV_LEN; + + buf++; + + DRM_DEBUG("vrl: %d, Revoked KSVs: %d\n", vrl_idx++, + vrl_ksv_cnt); + memcpy((*revoked_ksv_list) + (ksv_count * DRM_HDCP_KSV_LEN), + buf, vrl_ksv_sz); + + ksv_count += vrl_ksv_cnt; + buf += vrl_ksv_sz; + + parsed_bytes += (vrl_ksv_sz + 1); + } while (parsed_bytes < vrls_length); + + return ksv_count; +} + +static inline u32 get_vrl_length(const u8 *buf) +{ + return drm_hdcp_be24_to_cpu(buf); +} + +static int drm_hdcp_parse_hdcp1_srm(const u8 *buf, size_t count, + u8 **revoked_ksv_list, u32 *revoked_ksv_cnt) +{ + struct hdcp_srm_header *header; + u32 vrl_length, ksv_count; + + if (count < (sizeof(struct hdcp_srm_header) + + DRM_HDCP_1_4_VRL_LENGTH_SIZE + DRM_HDCP_1_4_DCP_SIG_SIZE)) { + DRM_ERROR("Invalid blob length\n"); + return -EINVAL; + } + + header = (struct hdcp_srm_header *)buf; + DRM_DEBUG("SRM ID: 0x%x, SRM Ver: 0x%x, SRM Gen No: 0x%x\n", + header->srm_id, + be16_to_cpu(header->srm_version), header->srm_gen_no); + + WARN_ON(header->reserved); + + buf = buf + sizeof(*header); + vrl_length = get_vrl_length(buf); + if (count < (sizeof(struct hdcp_srm_header) + vrl_length) || + vrl_length < (DRM_HDCP_1_4_VRL_LENGTH_SIZE + + DRM_HDCP_1_4_DCP_SIG_SIZE)) { + DRM_ERROR("Invalid blob length or vrl length\n"); + return -EINVAL; + } + + /* Length of the all vrls combined */ + vrl_length -= (DRM_HDCP_1_4_VRL_LENGTH_SIZE + + DRM_HDCP_1_4_DCP_SIG_SIZE); + + if (!vrl_length) { + DRM_ERROR("No vrl found\n"); + return -EINVAL; + } + + buf += DRM_HDCP_1_4_VRL_LENGTH_SIZE; + ksv_count = drm_hdcp_get_revoked_ksv_count(buf, vrl_length); + if (!ksv_count) { + DRM_DEBUG("Revoked KSV count is 0\n"); + return 0; + } + + *revoked_ksv_list = kcalloc(ksv_count, DRM_HDCP_KSV_LEN, GFP_KERNEL); + if (!*revoked_ksv_list) { + DRM_ERROR("Out of Memory\n"); + return -ENOMEM; + } + + if (drm_hdcp_get_revoked_ksvs(buf, revoked_ksv_list, + vrl_length) != ksv_count) { + *revoked_ksv_cnt = 0; + kfree(*revoked_ksv_list); + return -EINVAL; + } + + *revoked_ksv_cnt = ksv_count; + return 0; +} + +static int drm_hdcp_parse_hdcp2_srm(const u8 *buf, size_t count, + u8 **revoked_ksv_list, u32 *revoked_ksv_cnt) +{ + struct hdcp_srm_header *header; + u32 vrl_length, ksv_count, ksv_sz; + + if (count < (sizeof(struct hdcp_srm_header) + + DRM_HDCP_2_VRL_LENGTH_SIZE + DRM_HDCP_2_DCP_SIG_SIZE)) { + DRM_ERROR("Invalid blob length\n"); + return -EINVAL; + } + + header = (struct hdcp_srm_header *)buf; + DRM_DEBUG("SRM ID: 0x%x, SRM Ver: 0x%x, SRM Gen No: 0x%x\n", + header->srm_id & DRM_HDCP_SRM_ID_MASK, + be16_to_cpu(header->srm_version), header->srm_gen_no); + + if (header->reserved) + return -EINVAL; + + buf = buf + sizeof(*header); + vrl_length = get_vrl_length(buf); + + if (count < (sizeof(struct hdcp_srm_header) + vrl_length) || + vrl_length < (DRM_HDCP_2_VRL_LENGTH_SIZE + + DRM_HDCP_2_DCP_SIG_SIZE)) { + DRM_ERROR("Invalid blob length or vrl length\n"); + return -EINVAL; + } + + /* Length of the all vrls combined */ + vrl_length -= (DRM_HDCP_2_VRL_LENGTH_SIZE + + DRM_HDCP_2_DCP_SIG_SIZE); + + if (!vrl_length) { + DRM_ERROR("No vrl found\n"); + return -EINVAL; + } + + buf += DRM_HDCP_2_VRL_LENGTH_SIZE; + ksv_count = (*buf << 2) | DRM_HDCP_2_KSV_COUNT_2_LSBITS(*(buf + 1)); + if (!ksv_count) { + DRM_DEBUG("Revoked KSV count is 0\n"); + return 0; + } + + *revoked_ksv_list = kcalloc(ksv_count, DRM_HDCP_KSV_LEN, GFP_KERNEL); + if (!*revoked_ksv_list) { + DRM_ERROR("Out of Memory\n"); + return -ENOMEM; + } + + ksv_sz = ksv_count * DRM_HDCP_KSV_LEN; + buf += DRM_HDCP_2_NO_OF_DEV_PLUS_RESERVED_SZ; + + DRM_DEBUG("Revoked KSVs: %d\n", ksv_count); + memcpy(*revoked_ksv_list, buf, ksv_sz); + + *revoked_ksv_cnt = ksv_count; + return 0; +} + +static inline bool is_srm_version_hdcp1(const u8 *buf) +{ + return *buf == (u8)(DRM_HDCP_1_4_SRM_ID << 4); +} + +static inline bool is_srm_version_hdcp2(const u8 *buf) +{ + return *buf == (u8)(DRM_HDCP_2_SRM_ID << 4 | DRM_HDCP_2_INDICATOR); +} + +static int drm_hdcp_srm_update(const u8 *buf, size_t count, + u8 **revoked_ksv_list, u32 *revoked_ksv_cnt) +{ + if (count < sizeof(struct hdcp_srm_header)) + return -EINVAL; + + if (is_srm_version_hdcp1(buf)) + return drm_hdcp_parse_hdcp1_srm(buf, count, revoked_ksv_list, + revoked_ksv_cnt); + else if (is_srm_version_hdcp2(buf)) + return drm_hdcp_parse_hdcp2_srm(buf, count, revoked_ksv_list, + revoked_ksv_cnt); + else + return -EINVAL; +} + +static int drm_hdcp_request_srm(struct drm_device *drm_dev, + u8 **revoked_ksv_list, u32 *revoked_ksv_cnt) +{ + char fw_name[36] = "display_hdcp_srm.bin"; + const struct firmware *fw; + int ret; + + ret = request_firmware_direct(&fw, (const char *)fw_name, + drm_dev->dev); + if (ret < 0) { + *revoked_ksv_cnt = 0; + *revoked_ksv_list = NULL; + ret = 0; + goto exit; + } + + if (fw->size && fw->data) + ret = drm_hdcp_srm_update(fw->data, fw->size, revoked_ksv_list, + revoked_ksv_cnt); + +exit: + release_firmware(fw); + return ret; +} + +/** + * drm_hdcp_check_ksvs_revoked - Check the revoked status of the IDs + * + * @drm_dev: drm_device for which HDCP revocation check is requested + * @ksvs: List of KSVs (HDCP receiver IDs) + * @ksv_count: KSV count passed in through @ksvs + * + * This function reads the HDCP System renewability Message(SRM Table) + * from userspace as a firmware and parses it for the revoked HDCP + * KSVs(Receiver IDs) detected by DCP LLC. Once the revoked KSVs are known, + * revoked state of the KSVs in the list passed in by display drivers are + * decided and response is sent. + * + * SRM should be presented in the name of "display_hdcp_srm.bin". + * + * Format of the SRM table, that userspace needs to write into the binary file, + * is defined at: + * 1. Renewability chapter on 55th page of HDCP 1.4 specification + * https://www.digital-cp.com/sites/default/files/specifications/HDCP%20Specification%20Rev1_4_Secure.pdf + * 2. Renewability chapter on 63rd page of HDCP 2.2 specification + * https://www.digital-cp.com/sites/default/files/specifications/HDCP%20on%20HDMI%20Specification%20Rev2_2_Final1.pdf + * + * Returns: + * Count of the revoked KSVs or -ve error number in case of the failure. + */ +int drm_hdcp_check_ksvs_revoked(struct drm_device *drm_dev, u8 *ksvs, + u32 ksv_count) +{ + u32 revoked_ksv_cnt = 0, i, j; + u8 *revoked_ksv_list = NULL; + int ret = 0; + + ret = drm_hdcp_request_srm(drm_dev, &revoked_ksv_list, + &revoked_ksv_cnt); + if (ret) + return ret; + + /* revoked_ksv_cnt will be zero when above function failed */ + for (i = 0; i < revoked_ksv_cnt; i++) + for (j = 0; j < ksv_count; j++) + if (!memcmp(&ksvs[j * DRM_HDCP_KSV_LEN], + &revoked_ksv_list[i * DRM_HDCP_KSV_LEN], + DRM_HDCP_KSV_LEN)) { + DRM_DEBUG("Revoked KSV is "); + drm_hdcp_print_ksv(&ksvs[j * DRM_HDCP_KSV_LEN]); + ret++; + } + + kfree(revoked_ksv_list); + return ret; +} +EXPORT_SYMBOL_GPL(drm_hdcp_check_ksvs_revoked); + +static struct drm_prop_enum_list drm_cp_enum_list[] = { + { DRM_MODE_CONTENT_PROTECTION_UNDESIRED, "Undesired" }, + { DRM_MODE_CONTENT_PROTECTION_DESIRED, "Desired" }, + { DRM_MODE_CONTENT_PROTECTION_ENABLED, "Enabled" }, +}; +DRM_ENUM_NAME_FN(drm_get_content_protection_name, drm_cp_enum_list) + +static struct drm_prop_enum_list drm_hdcp_content_type_enum_list[] = { + { DRM_MODE_HDCP_CONTENT_TYPE0, "HDCP Type0" }, + { DRM_MODE_HDCP_CONTENT_TYPE1, "HDCP Type1" }, +}; +DRM_ENUM_NAME_FN(drm_get_hdcp_content_type_name, + drm_hdcp_content_type_enum_list) + +/** + * drm_connector_attach_content_protection_property - attach content protection + * property + * + * @connector: connector to attach CP property on. + * @hdcp_content_type: is HDCP Content Type property needed for connector + * + * This is used to add support for content protection on select connectors. + * Content Protection is intentionally vague to allow for different underlying + * technologies, however it is most implemented by HDCP. + * + * When hdcp_content_type is true enum property called HDCP Content Type is + * created (if it is not already) and attached to the connector. + * + * This property is used for sending the protected content's stream type + * from userspace to kernel on selected connectors. Protected content provider + * will decide their type of their content and declare the same to kernel. + * + * Content type will be used during the HDCP 2.2 authentication. + * Content type will be set to &drm_connector_state.hdcp_content_type. + * + * The content protection will be set to &drm_connector_state.content_protection + * + * When kernel triggered content protection state change like DESIRED->ENABLED + * and ENABLED->DESIRED, will use drm_hdcp_update_content_protection() to update + * the content protection state of a connector. + * + * Returns: + * Zero on success, negative errno on failure. + */ +int drm_connector_attach_content_protection_property( + struct drm_connector *connector, bool hdcp_content_type) +{ + struct drm_device *dev = connector->dev; + struct drm_property *prop = + dev->mode_config.content_protection_property; + + if (!prop) + prop = drm_property_create_enum(dev, 0, "Content Protection", + drm_cp_enum_list, + ARRAY_SIZE(drm_cp_enum_list)); + if (!prop) + return -ENOMEM; + + drm_object_attach_property(&connector->base, prop, + DRM_MODE_CONTENT_PROTECTION_UNDESIRED); + dev->mode_config.content_protection_property = prop; + + if (!hdcp_content_type) + return 0; + + prop = dev->mode_config.hdcp_content_type_property; + if (!prop) + prop = drm_property_create_enum(dev, 0, "HDCP Content Type", + drm_hdcp_content_type_enum_list, + ARRAY_SIZE( + drm_hdcp_content_type_enum_list)); + if (!prop) + return -ENOMEM; + + drm_object_attach_property(&connector->base, prop, + DRM_MODE_HDCP_CONTENT_TYPE0); + dev->mode_config.hdcp_content_type_property = prop; + + return 0; +} +EXPORT_SYMBOL(drm_connector_attach_content_protection_property); + +/** + * drm_hdcp_update_content_protection - Updates the content protection state + * of a connector + * + * @connector: drm_connector on which content protection state needs an update + * @val: New state of the content protection property + * + * This function can be used by display drivers, to update the kernel triggered + * content protection state changes of a drm_connector such as DESIRED->ENABLED + * and ENABLED->DESIRED. No uevent for DESIRED->UNDESIRED or ENABLED->UNDESIRED, + * as userspace is triggering such state change and kernel performs it without + * fail.This function update the new state of the property into the connector's + * state and generate an uevent to notify the userspace. + */ +void drm_hdcp_update_content_protection(struct drm_connector *connector, + u64 val) +{ + struct drm_device *dev = connector->dev; + struct drm_connector_state *state = connector->state; + + WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex)); + if (state->content_protection == val) + return; + + state->content_protection = val; + drm_sysfs_connector_status_event(connector, + dev->mode_config.content_protection_property); +} +EXPORT_SYMBOL(drm_hdcp_update_content_protection); diff --git a/drivers/gpu/drm/display/drm_hdmi_helper.c b/drivers/gpu/drm/display/drm_hdmi_helper.c new file mode 100644 index 000000000..faf5e9efa --- /dev/null +++ b/drivers/gpu/drm/display/drm_hdmi_helper.c @@ -0,0 +1,197 @@ +// SPDX-License-Identifier: MIT + +#include <linux/module.h> + +#include <drm/display/drm_hdmi_helper.h> +#include <drm/drm_connector.h> +#include <drm/drm_edid.h> +#include <drm/drm_modes.h> +#include <drm/drm_print.h> +#include <drm/drm_property.h> + +static inline bool is_eotf_supported(u8 output_eotf, u8 sink_eotf) +{ + return sink_eotf & BIT(output_eotf); +} + +/** + * drm_hdmi_infoframe_set_hdr_metadata() - fill an HDMI DRM infoframe with + * HDR metadata from userspace + * @frame: HDMI DRM infoframe + * @conn_state: Connector state containing HDR metadata + * + * Return: 0 on success or a negative error code on failure. + */ +int drm_hdmi_infoframe_set_hdr_metadata(struct hdmi_drm_infoframe *frame, + const struct drm_connector_state *conn_state) +{ + struct drm_connector *connector; + struct hdr_output_metadata *hdr_metadata; + int err; + + if (!frame || !conn_state) + return -EINVAL; + + connector = conn_state->connector; + + if (!conn_state->hdr_output_metadata) + return -EINVAL; + + hdr_metadata = conn_state->hdr_output_metadata->data; + + if (!hdr_metadata || !connector) + return -EINVAL; + + /* Sink EOTF is Bit map while infoframe is absolute values */ + if (!is_eotf_supported(hdr_metadata->hdmi_metadata_type1.eotf, + connector->hdr_sink_metadata.hdmi_type1.eotf)) + DRM_DEBUG_KMS("Unknown EOTF %d\n", hdr_metadata->hdmi_metadata_type1.eotf); + + err = hdmi_drm_infoframe_init(frame); + if (err < 0) + return err; + + frame->eotf = hdr_metadata->hdmi_metadata_type1.eotf; + frame->metadata_type = hdr_metadata->hdmi_metadata_type1.metadata_type; + + BUILD_BUG_ON(sizeof(frame->display_primaries) != + sizeof(hdr_metadata->hdmi_metadata_type1.display_primaries)); + BUILD_BUG_ON(sizeof(frame->white_point) != + sizeof(hdr_metadata->hdmi_metadata_type1.white_point)); + + memcpy(&frame->display_primaries, + &hdr_metadata->hdmi_metadata_type1.display_primaries, + sizeof(frame->display_primaries)); + + memcpy(&frame->white_point, + &hdr_metadata->hdmi_metadata_type1.white_point, + sizeof(frame->white_point)); + + frame->max_display_mastering_luminance = + hdr_metadata->hdmi_metadata_type1.max_display_mastering_luminance; + frame->min_display_mastering_luminance = + hdr_metadata->hdmi_metadata_type1.min_display_mastering_luminance; + frame->max_fall = hdr_metadata->hdmi_metadata_type1.max_fall; + frame->max_cll = hdr_metadata->hdmi_metadata_type1.max_cll; + + return 0; +} +EXPORT_SYMBOL(drm_hdmi_infoframe_set_hdr_metadata); + +/* HDMI Colorspace Spec Definitions */ +#define FULL_COLORIMETRY_MASK 0x1FF +#define NORMAL_COLORIMETRY_MASK 0x3 +#define EXTENDED_COLORIMETRY_MASK 0x7 +#define EXTENDED_ACE_COLORIMETRY_MASK 0xF + +#define C(x) ((x) << 0) +#define EC(x) ((x) << 2) +#define ACE(x) ((x) << 5) + +#define HDMI_COLORIMETRY_NO_DATA 0x0 +#define HDMI_COLORIMETRY_SMPTE_170M_YCC (C(1) | EC(0) | ACE(0)) +#define HDMI_COLORIMETRY_BT709_YCC (C(2) | EC(0) | ACE(0)) +#define HDMI_COLORIMETRY_XVYCC_601 (C(3) | EC(0) | ACE(0)) +#define HDMI_COLORIMETRY_XVYCC_709 (C(3) | EC(1) | ACE(0)) +#define HDMI_COLORIMETRY_SYCC_601 (C(3) | EC(2) | ACE(0)) +#define HDMI_COLORIMETRY_OPYCC_601 (C(3) | EC(3) | ACE(0)) +#define HDMI_COLORIMETRY_OPRGB (C(3) | EC(4) | ACE(0)) +#define HDMI_COLORIMETRY_BT2020_CYCC (C(3) | EC(5) | ACE(0)) +#define HDMI_COLORIMETRY_BT2020_RGB (C(3) | EC(6) | ACE(0)) +#define HDMI_COLORIMETRY_BT2020_YCC (C(3) | EC(6) | ACE(0)) +#define HDMI_COLORIMETRY_DCI_P3_RGB_D65 (C(3) | EC(7) | ACE(0)) +#define HDMI_COLORIMETRY_DCI_P3_RGB_THEATER (C(3) | EC(7) | ACE(1)) + +static const u32 hdmi_colorimetry_val[] = { + [DRM_MODE_COLORIMETRY_NO_DATA] = HDMI_COLORIMETRY_NO_DATA, + [DRM_MODE_COLORIMETRY_SMPTE_170M_YCC] = HDMI_COLORIMETRY_SMPTE_170M_YCC, + [DRM_MODE_COLORIMETRY_BT709_YCC] = HDMI_COLORIMETRY_BT709_YCC, + [DRM_MODE_COLORIMETRY_XVYCC_601] = HDMI_COLORIMETRY_XVYCC_601, + [DRM_MODE_COLORIMETRY_XVYCC_709] = HDMI_COLORIMETRY_XVYCC_709, + [DRM_MODE_COLORIMETRY_SYCC_601] = HDMI_COLORIMETRY_SYCC_601, + [DRM_MODE_COLORIMETRY_OPYCC_601] = HDMI_COLORIMETRY_OPYCC_601, + [DRM_MODE_COLORIMETRY_OPRGB] = HDMI_COLORIMETRY_OPRGB, + [DRM_MODE_COLORIMETRY_BT2020_CYCC] = HDMI_COLORIMETRY_BT2020_CYCC, + [DRM_MODE_COLORIMETRY_BT2020_RGB] = HDMI_COLORIMETRY_BT2020_RGB, + [DRM_MODE_COLORIMETRY_BT2020_YCC] = HDMI_COLORIMETRY_BT2020_YCC, +}; + +#undef C +#undef EC +#undef ACE + +/** + * drm_hdmi_avi_infoframe_colorimetry() - fill the HDMI AVI infoframe + * colorimetry information + * @frame: HDMI AVI infoframe + * @conn_state: connector state + */ +void drm_hdmi_avi_infoframe_colorimetry(struct hdmi_avi_infoframe *frame, + const struct drm_connector_state *conn_state) +{ + u32 colorimetry_val; + u32 colorimetry_index = conn_state->colorspace & FULL_COLORIMETRY_MASK; + + if (colorimetry_index >= ARRAY_SIZE(hdmi_colorimetry_val)) + colorimetry_val = HDMI_COLORIMETRY_NO_DATA; + else + colorimetry_val = hdmi_colorimetry_val[colorimetry_index]; + + frame->colorimetry = colorimetry_val & NORMAL_COLORIMETRY_MASK; + /* + * ToDo: Extend it for ACE formats as well. Modify the infoframe + * structure and extend it in drivers/video/hdmi + */ + frame->extended_colorimetry = (colorimetry_val >> 2) & + EXTENDED_COLORIMETRY_MASK; +} +EXPORT_SYMBOL(drm_hdmi_avi_infoframe_colorimetry); + +/** + * drm_hdmi_avi_infoframe_bars() - fill the HDMI AVI infoframe + * bar information + * @frame: HDMI AVI infoframe + * @conn_state: connector state + */ +void drm_hdmi_avi_infoframe_bars(struct hdmi_avi_infoframe *frame, + const struct drm_connector_state *conn_state) +{ + frame->right_bar = conn_state->tv.margins.right; + frame->left_bar = conn_state->tv.margins.left; + frame->top_bar = conn_state->tv.margins.top; + frame->bottom_bar = conn_state->tv.margins.bottom; +} +EXPORT_SYMBOL(drm_hdmi_avi_infoframe_bars); + +/** + * drm_hdmi_avi_infoframe_content_type() - fill the HDMI AVI infoframe + * content type information, based + * on correspondent DRM property. + * @frame: HDMI AVI infoframe + * @conn_state: DRM display connector state + * + */ +void drm_hdmi_avi_infoframe_content_type(struct hdmi_avi_infoframe *frame, + const struct drm_connector_state *conn_state) +{ + switch (conn_state->content_type) { + case DRM_MODE_CONTENT_TYPE_GRAPHICS: + frame->content_type = HDMI_CONTENT_TYPE_GRAPHICS; + break; + case DRM_MODE_CONTENT_TYPE_CINEMA: + frame->content_type = HDMI_CONTENT_TYPE_CINEMA; + break; + case DRM_MODE_CONTENT_TYPE_GAME: + frame->content_type = HDMI_CONTENT_TYPE_GAME; + break; + case DRM_MODE_CONTENT_TYPE_PHOTO: + frame->content_type = HDMI_CONTENT_TYPE_PHOTO; + break; + default: + /* Graphics is the default(0) */ + frame->content_type = HDMI_CONTENT_TYPE_GRAPHICS; + } + + frame->itc = conn_state->content_type != DRM_MODE_CONTENT_TYPE_NO_DATA; +} +EXPORT_SYMBOL(drm_hdmi_avi_infoframe_content_type); diff --git a/drivers/gpu/drm/display/drm_scdc_helper.c b/drivers/gpu/drm/display/drm_scdc_helper.c new file mode 100644 index 000000000..c3ad4ab2b --- /dev/null +++ b/drivers/gpu/drm/display/drm_scdc_helper.c @@ -0,0 +1,263 @@ +/* + * Copyright (c) 2015 NVIDIA Corporation. All rights reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sub license, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + */ + +#include <linux/i2c.h> +#include <linux/slab.h> +#include <linux/delay.h> + +#include <drm/display/drm_scdc_helper.h> +#include <drm/drm_print.h> + +/** + * DOC: scdc helpers + * + * Status and Control Data Channel (SCDC) is a mechanism introduced by the + * HDMI 2.0 specification. It is a point-to-point protocol that allows the + * HDMI source and HDMI sink to exchange data. The same I2C interface that + * is used to access EDID serves as the transport mechanism for SCDC. + * + * Note: The SCDC status is going to be lost when the display is + * disconnected. This can happen physically when the user disconnects + * the cable, but also when a display is switched on (such as waking up + * a TV). + * + * This is further complicated by the fact that, upon a disconnection / + * reconnection, KMS won't change the mode on its own. This means that + * one can't just rely on setting the SCDC status on enable, but also + * has to track the connector status changes using interrupts and + * restore the SCDC status. The typical solution for this is to trigger an + * empty modeset in drm_connector_helper_funcs.detect_ctx(), like what vc4 does + * in vc4_hdmi_reset_link(). + */ + +#define SCDC_I2C_SLAVE_ADDRESS 0x54 + +/** + * drm_scdc_read - read a block of data from SCDC + * @adapter: I2C controller + * @offset: start offset of block to read + * @buffer: return location for the block to read + * @size: size of the block to read + * + * Reads a block of data from SCDC, starting at a given offset. + * + * Returns: + * 0 on success, negative error code on failure. + */ +ssize_t drm_scdc_read(struct i2c_adapter *adapter, u8 offset, void *buffer, + size_t size) +{ + int ret; + struct i2c_msg msgs[2] = { + { + .addr = SCDC_I2C_SLAVE_ADDRESS, + .flags = 0, + .len = 1, + .buf = &offset, + }, { + .addr = SCDC_I2C_SLAVE_ADDRESS, + .flags = I2C_M_RD, + .len = size, + .buf = buffer, + } + }; + + ret = i2c_transfer(adapter, msgs, ARRAY_SIZE(msgs)); + if (ret < 0) + return ret; + if (ret != ARRAY_SIZE(msgs)) + return -EPROTO; + + return 0; +} +EXPORT_SYMBOL(drm_scdc_read); + +/** + * drm_scdc_write - write a block of data to SCDC + * @adapter: I2C controller + * @offset: start offset of block to write + * @buffer: block of data to write + * @size: size of the block to write + * + * Writes a block of data to SCDC, starting at a given offset. + * + * Returns: + * 0 on success, negative error code on failure. + */ +ssize_t drm_scdc_write(struct i2c_adapter *adapter, u8 offset, + const void *buffer, size_t size) +{ + struct i2c_msg msg = { + .addr = SCDC_I2C_SLAVE_ADDRESS, + .flags = 0, + .len = 1 + size, + .buf = NULL, + }; + void *data; + int err; + + data = kmalloc(1 + size, GFP_KERNEL); + if (!data) + return -ENOMEM; + + msg.buf = data; + + memcpy(data, &offset, sizeof(offset)); + memcpy(data + 1, buffer, size); + + err = i2c_transfer(adapter, &msg, 1); + + kfree(data); + + if (err < 0) + return err; + if (err != 1) + return -EPROTO; + + return 0; +} +EXPORT_SYMBOL(drm_scdc_write); + +/** + * drm_scdc_get_scrambling_status - what is status of scrambling? + * @adapter: I2C adapter for DDC channel + * + * Reads the scrambler status over SCDC, and checks the + * scrambling status. + * + * Returns: + * True if the scrambling is enabled, false otherwise. + */ +bool drm_scdc_get_scrambling_status(struct i2c_adapter *adapter) +{ + u8 status; + int ret; + + ret = drm_scdc_readb(adapter, SCDC_SCRAMBLER_STATUS, &status); + if (ret < 0) { + DRM_DEBUG_KMS("Failed to read scrambling status: %d\n", ret); + return false; + } + + return status & SCDC_SCRAMBLING_STATUS; +} +EXPORT_SYMBOL(drm_scdc_get_scrambling_status); + +/** + * drm_scdc_set_scrambling - enable scrambling + * @adapter: I2C adapter for DDC channel + * @enable: bool to indicate if scrambling is to be enabled/disabled + * + * Writes the TMDS config register over SCDC channel, and: + * enables scrambling when enable = 1 + * disables scrambling when enable = 0 + * + * Returns: + * True if scrambling is set/reset successfully, false otherwise. + */ +bool drm_scdc_set_scrambling(struct i2c_adapter *adapter, bool enable) +{ + u8 config; + int ret; + + ret = drm_scdc_readb(adapter, SCDC_TMDS_CONFIG, &config); + if (ret < 0) { + DRM_DEBUG_KMS("Failed to read TMDS config: %d\n", ret); + return false; + } + + if (enable) + config |= SCDC_SCRAMBLING_ENABLE; + else + config &= ~SCDC_SCRAMBLING_ENABLE; + + ret = drm_scdc_writeb(adapter, SCDC_TMDS_CONFIG, config); + if (ret < 0) { + DRM_DEBUG_KMS("Failed to enable scrambling: %d\n", ret); + return false; + } + + return true; +} +EXPORT_SYMBOL(drm_scdc_set_scrambling); + +/** + * drm_scdc_set_high_tmds_clock_ratio - set TMDS clock ratio + * @adapter: I2C adapter for DDC channel + * @set: ret or reset the high clock ratio + * + * + * TMDS clock ratio calculations go like this: + * TMDS character = 10 bit TMDS encoded value + * + * TMDS character rate = The rate at which TMDS characters are + * transmitted (Mcsc) + * + * TMDS bit rate = 10x TMDS character rate + * + * As per the spec: + * TMDS clock rate for pixel clock < 340 MHz = 1x the character + * rate = 1/10 pixel clock rate + * + * TMDS clock rate for pixel clock > 340 MHz = 0.25x the character + * rate = 1/40 pixel clock rate + * + * Writes to the TMDS config register over SCDC channel, and: + * sets TMDS clock ratio to 1/40 when set = 1 + * + * sets TMDS clock ratio to 1/10 when set = 0 + * + * Returns: + * True if write is successful, false otherwise. + */ +bool drm_scdc_set_high_tmds_clock_ratio(struct i2c_adapter *adapter, bool set) +{ + u8 config; + int ret; + + ret = drm_scdc_readb(adapter, SCDC_TMDS_CONFIG, &config); + if (ret < 0) { + DRM_DEBUG_KMS("Failed to read TMDS config: %d\n", ret); + return false; + } + + if (set) + config |= SCDC_TMDS_BIT_CLOCK_RATIO_BY_40; + else + config &= ~SCDC_TMDS_BIT_CLOCK_RATIO_BY_40; + + ret = drm_scdc_writeb(adapter, SCDC_TMDS_CONFIG, config); + if (ret < 0) { + DRM_DEBUG_KMS("Failed to set TMDS clock ratio: %d\n", ret); + return false; + } + + /* + * The spec says that a source should wait minimum 1ms and maximum + * 100ms after writing the TMDS config for clock ratio. Lets allow a + * wait of up to 2ms here. + */ + usleep_range(1000, 2000); + return true; +} +EXPORT_SYMBOL(drm_scdc_set_high_tmds_clock_ratio); |