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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/usb/typec/bus.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/typec/bus.c')
-rw-r--r-- | drivers/usb/typec/bus.c | 420 |
1 files changed, 420 insertions, 0 deletions
diff --git a/drivers/usb/typec/bus.c b/drivers/usb/typec/bus.c new file mode 100644 index 000000000..69442a813 --- /dev/null +++ b/drivers/usb/typec/bus.c @@ -0,0 +1,420 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Bus for USB Type-C Alternate Modes + * + * Copyright (C) 2018 Intel Corporation + * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com> + */ + +#include <linux/usb/pd_vdo.h> + +#include "bus.h" +#include "class.h" +#include "mux.h" + +static inline int +typec_altmode_set_mux(struct altmode *alt, unsigned long conf, void *data) +{ + struct typec_mux_state state; + + if (!alt->mux) + return 0; + + state.alt = &alt->adev; + state.mode = conf; + state.data = data; + + return typec_mux_set(alt->mux, &state); +} + +static int typec_altmode_set_state(struct typec_altmode *adev, + unsigned long conf, void *data) +{ + bool is_port = is_typec_port(adev->dev.parent); + struct altmode *port_altmode; + + port_altmode = is_port ? to_altmode(adev) : to_altmode(adev)->partner; + + return typec_altmode_set_mux(port_altmode, conf, data); +} + +/* -------------------------------------------------------------------------- */ +/* Common API */ + +/** + * typec_altmode_notify - Communication between the OS and alternate mode driver + * @adev: Handle to the alternate mode + * @conf: Alternate mode specific configuration value + * @data: Alternate mode specific data + * + * The primary purpose for this function is to allow the alternate mode drivers + * to tell which pin configuration has been negotiated with the partner. That + * information will then be used for example to configure the muxes. + * Communication to the other direction is also possible, and low level device + * drivers can also send notifications to the alternate mode drivers. The actual + * communication will be specific for every SVID. + */ +int typec_altmode_notify(struct typec_altmode *adev, + unsigned long conf, void *data) +{ + bool is_port; + struct altmode *altmode; + struct altmode *partner; + int ret; + + if (!adev) + return 0; + + altmode = to_altmode(adev); + + if (!altmode->partner) + return -ENODEV; + + is_port = is_typec_port(adev->dev.parent); + partner = altmode->partner; + + ret = typec_altmode_set_mux(is_port ? altmode : partner, conf, data); + if (ret) + return ret; + + if (partner->adev.ops && partner->adev.ops->notify) + return partner->adev.ops->notify(&partner->adev, conf, data); + + return 0; +} +EXPORT_SYMBOL_GPL(typec_altmode_notify); + +/** + * typec_altmode_enter - Enter Mode + * @adev: The alternate mode + * @vdo: VDO for the Enter Mode command + * + * The alternate mode drivers use this function to enter mode. The port drivers + * use this to inform the alternate mode drivers that the partner has initiated + * Enter Mode command. If the alternate mode does not require VDO, @vdo must be + * NULL. + */ +int typec_altmode_enter(struct typec_altmode *adev, u32 *vdo) +{ + struct altmode *partner = to_altmode(adev)->partner; + struct typec_altmode *pdev = &partner->adev; + int ret; + + if (!adev || adev->active) + return 0; + + if (!pdev->ops || !pdev->ops->enter) + return -EOPNOTSUPP; + + if (is_typec_port(pdev->dev.parent) && !pdev->active) + return -EPERM; + + /* Moving to USB Safe State */ + ret = typec_altmode_set_state(adev, TYPEC_STATE_SAFE, NULL); + if (ret) + return ret; + + /* Enter Mode */ + return pdev->ops->enter(pdev, vdo); +} +EXPORT_SYMBOL_GPL(typec_altmode_enter); + +/** + * typec_altmode_exit - Exit Mode + * @adev: The alternate mode + * + * The partner of @adev has initiated Exit Mode command. + */ +int typec_altmode_exit(struct typec_altmode *adev) +{ + struct altmode *partner = to_altmode(adev)->partner; + struct typec_altmode *pdev = &partner->adev; + int ret; + + if (!adev || !adev->active) + return 0; + + if (!pdev->ops || !pdev->ops->exit) + return -EOPNOTSUPP; + + /* Moving to USB Safe State */ + ret = typec_altmode_set_state(adev, TYPEC_STATE_SAFE, NULL); + if (ret) + return ret; + + /* Exit Mode command */ + return pdev->ops->exit(pdev); +} +EXPORT_SYMBOL_GPL(typec_altmode_exit); + +/** + * typec_altmode_attention - Attention command + * @adev: The alternate mode + * @vdo: VDO for the Attention command + * + * Notifies the partner of @adev about Attention command. + */ +int typec_altmode_attention(struct typec_altmode *adev, u32 vdo) +{ + struct altmode *partner = to_altmode(adev)->partner; + struct typec_altmode *pdev; + + if (!partner) + return -ENODEV; + + pdev = &partner->adev; + + if (pdev->ops && pdev->ops->attention) + pdev->ops->attention(pdev, vdo); + + return 0; +} +EXPORT_SYMBOL_GPL(typec_altmode_attention); + +/** + * typec_altmode_vdm - Send Vendor Defined Messages (VDM) to the partner + * @adev: Alternate mode handle + * @header: VDM Header + * @vdo: Array of Vendor Defined Data Objects + * @count: Number of Data Objects + * + * The alternate mode drivers use this function for SVID specific communication + * with the partner. The port drivers use it to deliver the Structured VDMs + * received from the partners to the alternate mode drivers. + */ +int typec_altmode_vdm(struct typec_altmode *adev, + const u32 header, const u32 *vdo, int count) +{ + struct typec_altmode *pdev; + struct altmode *altmode; + + if (!adev) + return 0; + + altmode = to_altmode(adev); + + if (!altmode->partner) + return -ENODEV; + + pdev = &altmode->partner->adev; + + if (!pdev->ops || !pdev->ops->vdm) + return -EOPNOTSUPP; + + return pdev->ops->vdm(pdev, header, vdo, count); +} +EXPORT_SYMBOL_GPL(typec_altmode_vdm); + +const struct typec_altmode * +typec_altmode_get_partner(struct typec_altmode *adev) +{ + if (!adev || !to_altmode(adev)->partner) + return NULL; + + return &to_altmode(adev)->partner->adev; +} +EXPORT_SYMBOL_GPL(typec_altmode_get_partner); + +/* -------------------------------------------------------------------------- */ +/* API for the alternate mode drivers */ + +/** + * typec_altmode_get_plug - Find cable plug alternate mode + * @adev: Handle to partner alternate mode + * @index: Cable plug index + * + * Increment reference count for cable plug alternate mode device. Returns + * handle to the cable plug alternate mode, or NULL if none is found. + */ +struct typec_altmode *typec_altmode_get_plug(struct typec_altmode *adev, + enum typec_plug_index index) +{ + struct altmode *port = to_altmode(adev)->partner; + + if (port->plug[index]) { + get_device(&port->plug[index]->adev.dev); + return &port->plug[index]->adev; + } + + return NULL; +} +EXPORT_SYMBOL_GPL(typec_altmode_get_plug); + +/** + * typec_altmode_put_plug - Decrement cable plug alternate mode reference count + * @plug: Handle to the cable plug alternate mode + */ +void typec_altmode_put_plug(struct typec_altmode *plug) +{ + if (plug) + put_device(&plug->dev); +} +EXPORT_SYMBOL_GPL(typec_altmode_put_plug); + +int __typec_altmode_register_driver(struct typec_altmode_driver *drv, + struct module *module) +{ + if (!drv->probe) + return -EINVAL; + + drv->driver.owner = module; + drv->driver.bus = &typec_bus; + + return driver_register(&drv->driver); +} +EXPORT_SYMBOL_GPL(__typec_altmode_register_driver); + +void typec_altmode_unregister_driver(struct typec_altmode_driver *drv) +{ + driver_unregister(&drv->driver); +} +EXPORT_SYMBOL_GPL(typec_altmode_unregister_driver); + +/* -------------------------------------------------------------------------- */ +/* API for the port drivers */ + +/** + * typec_match_altmode - Match SVID and mode to an array of alternate modes + * @altmodes: Array of alternate modes + * @n: Number of elements in the array, or -1 for NULL terminated arrays + * @svid: Standard or Vendor ID to match with + * @mode: Mode to match with + * + * Return pointer to an alternate mode with SVID matching @svid, or NULL when no + * match is found. + */ +struct typec_altmode *typec_match_altmode(struct typec_altmode **altmodes, + size_t n, u16 svid, u8 mode) +{ + int i; + + for (i = 0; i < n; i++) { + if (!altmodes[i]) + break; + if (altmodes[i]->svid == svid && altmodes[i]->mode == mode) + return altmodes[i]; + } + + return NULL; +} +EXPORT_SYMBOL_GPL(typec_match_altmode); + +/* -------------------------------------------------------------------------- */ + +static ssize_t +description_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct typec_altmode *alt = to_typec_altmode(dev); + + return sprintf(buf, "%s\n", alt->desc ? alt->desc : ""); +} +static DEVICE_ATTR_RO(description); + +static struct attribute *typec_attrs[] = { + &dev_attr_description.attr, + NULL +}; +ATTRIBUTE_GROUPS(typec); + +static int typec_match(struct device *dev, struct device_driver *driver) +{ + struct typec_altmode_driver *drv = to_altmode_driver(driver); + struct typec_altmode *altmode = to_typec_altmode(dev); + const struct typec_device_id *id; + + for (id = drv->id_table; id->svid; id++) + if (id->svid == altmode->svid && + (id->mode == TYPEC_ANY_MODE || id->mode == altmode->mode)) + return 1; + return 0; +} + +static int typec_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct typec_altmode *altmode = to_typec_altmode(dev); + + if (add_uevent_var(env, "SVID=%04X", altmode->svid)) + return -ENOMEM; + + if (add_uevent_var(env, "MODE=%u", altmode->mode)) + return -ENOMEM; + + return add_uevent_var(env, "MODALIAS=typec:id%04Xm%02X", + altmode->svid, altmode->mode); +} + +static int typec_altmode_create_links(struct altmode *alt) +{ + struct device *port_dev = &alt->partner->adev.dev; + struct device *dev = &alt->adev.dev; + int err; + + err = sysfs_create_link(&dev->kobj, &port_dev->kobj, "port"); + if (err) + return err; + + err = sysfs_create_link(&port_dev->kobj, &dev->kobj, "partner"); + if (err) + sysfs_remove_link(&dev->kobj, "port"); + + return err; +} + +static void typec_altmode_remove_links(struct altmode *alt) +{ + sysfs_remove_link(&alt->partner->adev.dev.kobj, "partner"); + sysfs_remove_link(&alt->adev.dev.kobj, "port"); +} + +static int typec_probe(struct device *dev) +{ + struct typec_altmode_driver *drv = to_altmode_driver(dev->driver); + struct typec_altmode *adev = to_typec_altmode(dev); + struct altmode *altmode = to_altmode(adev); + int ret; + + /* Fail if the port does not support the alternate mode */ + if (!altmode->partner) + return -ENODEV; + + ret = typec_altmode_create_links(altmode); + if (ret) { + dev_warn(dev, "failed to create symlinks\n"); + return ret; + } + + ret = drv->probe(adev); + if (ret) + typec_altmode_remove_links(altmode); + + return ret; +} + +static void typec_remove(struct device *dev) +{ + struct typec_altmode_driver *drv = to_altmode_driver(dev->driver); + struct typec_altmode *adev = to_typec_altmode(dev); + struct altmode *altmode = to_altmode(adev); + + typec_altmode_remove_links(altmode); + + if (drv->remove) + drv->remove(to_typec_altmode(dev)); + + if (adev->active) { + WARN_ON(typec_altmode_set_state(adev, TYPEC_STATE_SAFE, NULL)); + typec_altmode_update_active(adev, false); + } + + adev->desc = NULL; + adev->ops = NULL; +} + +struct bus_type typec_bus = { + .name = "typec", + .dev_groups = typec_groups, + .match = typec_match, + .uevent = typec_uevent, + .probe = typec_probe, + .remove = typec_remove, +}; |