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Diffstat (limited to '')
| -rw-r--r-- | drivers/hid/intel-ish-hid/ishtp/bus.c | 785 |
1 files changed, 785 insertions, 0 deletions
diff --git a/drivers/hid/intel-ish-hid/ishtp/bus.c b/drivers/hid/intel-ish-hid/ishtp/bus.c new file mode 100644 index 000000000..f546635e9 --- /dev/null +++ b/drivers/hid/intel-ish-hid/ishtp/bus.c @@ -0,0 +1,785 @@ +/* + * ISHTP bus driver + * + * Copyright (c) 2012-2016, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include "bus.h" +#include "ishtp-dev.h" +#include "client.h" +#include "hbm.h" + +static int ishtp_use_dma; +module_param_named(ishtp_use_dma, ishtp_use_dma, int, 0600); +MODULE_PARM_DESC(ishtp_use_dma, "Use DMA to send messages"); + +#define to_ishtp_cl_driver(d) container_of(d, struct ishtp_cl_driver, driver) +#define to_ishtp_cl_device(d) container_of(d, struct ishtp_cl_device, dev) +static bool ishtp_device_ready; + +/** + * ishtp_recv() - process ishtp message + * @dev: ishtp device + * + * If a message with valid header and size is received, then + * this function calls appropriate handler. The host or firmware + * address is zero, then they are host bus management message, + * otherwise they are message fo clients. + */ +void ishtp_recv(struct ishtp_device *dev) +{ + uint32_t msg_hdr; + struct ishtp_msg_hdr *ishtp_hdr; + + /* Read ISHTP header dword */ + msg_hdr = dev->ops->ishtp_read_hdr(dev); + if (!msg_hdr) + return; + + dev->ops->sync_fw_clock(dev); + + ishtp_hdr = (struct ishtp_msg_hdr *)&msg_hdr; + dev->ishtp_msg_hdr = msg_hdr; + + /* Sanity check: ISHTP frag. length in header */ + if (ishtp_hdr->length > dev->mtu) { + dev_err(dev->devc, + "ISHTP hdr - bad length: %u; dropped [%08X]\n", + (unsigned int)ishtp_hdr->length, msg_hdr); + return; + } + + /* ISHTP bus message */ + if (!ishtp_hdr->host_addr && !ishtp_hdr->fw_addr) + recv_hbm(dev, ishtp_hdr); + /* ISHTP fixed-client message */ + else if (!ishtp_hdr->host_addr) + recv_fixed_cl_msg(dev, ishtp_hdr); + else + /* ISHTP client message */ + recv_ishtp_cl_msg(dev, ishtp_hdr); +} +EXPORT_SYMBOL(ishtp_recv); + +/** + * ishtp_send_msg() - Send ishtp message + * @dev: ishtp device + * @hdr: Message header + * @msg: Message contents + * @ipc_send_compl: completion callback + * @ipc_send_compl_prm: completion callback parameter + * + * Send a multi fragment message via IPC. After sending the first fragment + * the completion callback is called to schedule transmit of next fragment. + * + * Return: This returns IPC send message status. + */ +int ishtp_send_msg(struct ishtp_device *dev, struct ishtp_msg_hdr *hdr, + void *msg, void(*ipc_send_compl)(void *), + void *ipc_send_compl_prm) +{ + unsigned char ipc_msg[IPC_FULL_MSG_SIZE]; + uint32_t drbl_val; + + drbl_val = dev->ops->ipc_get_header(dev, hdr->length + + sizeof(struct ishtp_msg_hdr), + 1); + + memcpy(ipc_msg, &drbl_val, sizeof(uint32_t)); + memcpy(ipc_msg + sizeof(uint32_t), hdr, sizeof(uint32_t)); + memcpy(ipc_msg + 2 * sizeof(uint32_t), msg, hdr->length); + return dev->ops->write(dev, ipc_send_compl, ipc_send_compl_prm, + ipc_msg, 2 * sizeof(uint32_t) + hdr->length); +} + +/** + * ishtp_write_message() - Send ishtp single fragment message + * @dev: ishtp device + * @hdr: Message header + * @buf: message data + * + * Send a single fragment message via IPC. This returns IPC send message + * status. + * + * Return: This returns IPC send message status. + */ +int ishtp_write_message(struct ishtp_device *dev, struct ishtp_msg_hdr *hdr, + unsigned char *buf) +{ + return ishtp_send_msg(dev, hdr, buf, NULL, NULL); +} + +/** + * ishtp_fw_cl_by_uuid() - locate index of fw client + * @dev: ishtp device + * @uuid: uuid of the client to search + * + * Search firmware client using UUID. + * + * Return: fw client index or -ENOENT if not found + */ +int ishtp_fw_cl_by_uuid(struct ishtp_device *dev, const uuid_le *uuid) +{ + int i, res = -ENOENT; + + for (i = 0; i < dev->fw_clients_num; ++i) { + if (uuid_le_cmp(*uuid, dev->fw_clients[i].props.protocol_name) + == 0) { + res = i; + break; + } + } + return res; +} +EXPORT_SYMBOL(ishtp_fw_cl_by_uuid); + +/** + * ishtp_fw_cl_by_id() - return index to fw_clients for client_id + * @dev: the ishtp device structure + * @client_id: fw client id to search + * + * Search firmware client using client id. + * + * Return: index on success, -ENOENT on failure. + */ +int ishtp_fw_cl_by_id(struct ishtp_device *dev, uint8_t client_id) +{ + int i, res = -ENOENT; + unsigned long flags; + + spin_lock_irqsave(&dev->fw_clients_lock, flags); + for (i = 0; i < dev->fw_clients_num; i++) { + if (dev->fw_clients[i].client_id == client_id) { + res = i; + break; + } + } + spin_unlock_irqrestore(&dev->fw_clients_lock, flags); + + return res; +} + +/** + * ishtp_cl_device_probe() - Bus probe() callback + * @dev: the device structure + * + * This is a bus probe callback and calls the drive probe function. + * + * Return: Return value from driver probe() call. + */ +static int ishtp_cl_device_probe(struct device *dev) +{ + struct ishtp_cl_device *device = to_ishtp_cl_device(dev); + struct ishtp_cl_driver *driver; + + if (!device) + return 0; + + driver = to_ishtp_cl_driver(dev->driver); + if (!driver || !driver->probe) + return -ENODEV; + + return driver->probe(device); +} + +/** + * ishtp_cl_device_remove() - Bus remove() callback + * @dev: the device structure + * + * This is a bus remove callback and calls the drive remove function. + * Since the ISH driver model supports only built in, this is + * primarily can be called during pci driver init failure. + * + * Return: Return value from driver remove() call. + */ +static int ishtp_cl_device_remove(struct device *dev) +{ + struct ishtp_cl_device *device = to_ishtp_cl_device(dev); + struct ishtp_cl_driver *driver; + + if (!device || !dev->driver) + return 0; + + if (device->event_cb) { + device->event_cb = NULL; + cancel_work_sync(&device->event_work); + } + + driver = to_ishtp_cl_driver(dev->driver); + if (!driver->remove) { + dev->driver = NULL; + + return 0; + } + + return driver->remove(device); +} + +/** + * ishtp_cl_device_suspend() - Bus suspend callback + * @dev: device + * + * Called during device suspend process. + * + * Return: Return value from driver suspend() call. + */ +static int ishtp_cl_device_suspend(struct device *dev) +{ + struct ishtp_cl_device *device = to_ishtp_cl_device(dev); + struct ishtp_cl_driver *driver; + int ret = 0; + + if (!device) + return 0; + + driver = to_ishtp_cl_driver(dev->driver); + if (driver && driver->driver.pm) { + if (driver->driver.pm->suspend) + ret = driver->driver.pm->suspend(dev); + } + + return ret; +} + +/** + * ishtp_cl_device_resume() - Bus resume callback + * @dev: device + * + * Called during device resume process. + * + * Return: Return value from driver resume() call. + */ +static int ishtp_cl_device_resume(struct device *dev) +{ + struct ishtp_cl_device *device = to_ishtp_cl_device(dev); + struct ishtp_cl_driver *driver; + int ret = 0; + + if (!device) + return 0; + + /* + * When ISH needs hard reset, it is done asynchrnously, hence bus + * resume will be called before full ISH resume + */ + if (device->ishtp_dev->resume_flag) + return 0; + + driver = to_ishtp_cl_driver(dev->driver); + if (driver && driver->driver.pm) { + if (driver->driver.pm->resume) + ret = driver->driver.pm->resume(dev); + } + + return ret; +} + +/** + * ishtp_cl_device_reset() - Reset callback + * @device: ishtp client device instance + * + * This is a callback when HW reset is done and the device need + * reinit. + * + * Return: Return value from driver reset() call. + */ +static int ishtp_cl_device_reset(struct ishtp_cl_device *device) +{ + struct ishtp_cl_driver *driver; + int ret = 0; + + device->event_cb = NULL; + cancel_work_sync(&device->event_work); + + driver = to_ishtp_cl_driver(device->dev.driver); + if (driver && driver->reset) + ret = driver->reset(device); + + return ret; +} + +static ssize_t modalias_show(struct device *dev, struct device_attribute *a, + char *buf) +{ + int len; + + len = snprintf(buf, PAGE_SIZE, "ishtp:%s\n", dev_name(dev)); + return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len; +} +static DEVICE_ATTR_RO(modalias); + +static struct attribute *ishtp_cl_dev_attrs[] = { + &dev_attr_modalias.attr, + NULL, +}; +ATTRIBUTE_GROUPS(ishtp_cl_dev); + +static int ishtp_cl_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + if (add_uevent_var(env, "MODALIAS=ishtp:%s", dev_name(dev))) + return -ENOMEM; + return 0; +} + +static const struct dev_pm_ops ishtp_cl_bus_dev_pm_ops = { + /* Suspend callbacks */ + .suspend = ishtp_cl_device_suspend, + .resume = ishtp_cl_device_resume, + /* Hibernate callbacks */ + .freeze = ishtp_cl_device_suspend, + .thaw = ishtp_cl_device_resume, + .restore = ishtp_cl_device_resume, +}; + +static struct bus_type ishtp_cl_bus_type = { + .name = "ishtp", + .dev_groups = ishtp_cl_dev_groups, + .probe = ishtp_cl_device_probe, + .remove = ishtp_cl_device_remove, + .pm = &ishtp_cl_bus_dev_pm_ops, + .uevent = ishtp_cl_uevent, +}; + +static void ishtp_cl_dev_release(struct device *dev) +{ + kfree(to_ishtp_cl_device(dev)); +} + +static const struct device_type ishtp_cl_device_type = { + .release = ishtp_cl_dev_release, +}; + +/** + * ishtp_bus_add_device() - Function to create device on bus + * @dev: ishtp device + * @uuid: uuid of the client + * @name: Name of the client + * + * Allocate ISHTP bus client device, attach it to uuid + * and register with ISHTP bus. + * + * Return: ishtp_cl_device pointer or NULL on failure + */ +static struct ishtp_cl_device *ishtp_bus_add_device(struct ishtp_device *dev, + uuid_le uuid, char *name) +{ + struct ishtp_cl_device *device; + int status; + unsigned long flags; + + spin_lock_irqsave(&dev->device_list_lock, flags); + list_for_each_entry(device, &dev->device_list, device_link) { + if (!strcmp(name, dev_name(&device->dev))) { + device->fw_client = &dev->fw_clients[ + dev->fw_client_presentation_num - 1]; + spin_unlock_irqrestore(&dev->device_list_lock, flags); + ishtp_cl_device_reset(device); + return device; + } + } + spin_unlock_irqrestore(&dev->device_list_lock, flags); + + device = kzalloc(sizeof(struct ishtp_cl_device), GFP_KERNEL); + if (!device) + return NULL; + + device->dev.parent = dev->devc; + device->dev.bus = &ishtp_cl_bus_type; + device->dev.type = &ishtp_cl_device_type; + device->ishtp_dev = dev; + + device->fw_client = + &dev->fw_clients[dev->fw_client_presentation_num - 1]; + + dev_set_name(&device->dev, "%s", name); + + spin_lock_irqsave(&dev->device_list_lock, flags); + list_add_tail(&device->device_link, &dev->device_list); + spin_unlock_irqrestore(&dev->device_list_lock, flags); + + status = device_register(&device->dev); + if (status) { + spin_lock_irqsave(&dev->device_list_lock, flags); + list_del(&device->device_link); + spin_unlock_irqrestore(&dev->device_list_lock, flags); + dev_err(dev->devc, "Failed to register ISHTP client device\n"); + put_device(&device->dev); + return NULL; + } + + ishtp_device_ready = true; + + return device; +} + +/** + * ishtp_bus_remove_device() - Function to relase device on bus + * @device: client device instance + * + * This is a counterpart of ishtp_bus_add_device. + * Device is unregistered. + * the device structure is freed in 'ishtp_cl_dev_release' function + * Called only during error in pci driver init path. + */ +static void ishtp_bus_remove_device(struct ishtp_cl_device *device) +{ + device_unregister(&device->dev); +} + +/** + * __ishtp_cl_driver_register() - Client driver register + * @driver: the client driver instance + * @owner: Owner of this driver module + * + * Once a client driver is probed, it created a client + * instance and registers with the bus. + * + * Return: Return value of driver_register or -ENODEV if not ready + */ +int __ishtp_cl_driver_register(struct ishtp_cl_driver *driver, + struct module *owner) +{ + int err; + + if (!ishtp_device_ready) + return -ENODEV; + + driver->driver.name = driver->name; + driver->driver.owner = owner; + driver->driver.bus = &ishtp_cl_bus_type; + + err = driver_register(&driver->driver); + if (err) + return err; + + return 0; +} +EXPORT_SYMBOL(__ishtp_cl_driver_register); + +/** + * ishtp_cl_driver_unregister() - Client driver unregister + * @driver: the client driver instance + * + * Unregister client during device removal process. + */ +void ishtp_cl_driver_unregister(struct ishtp_cl_driver *driver) +{ + driver_unregister(&driver->driver); +} +EXPORT_SYMBOL(ishtp_cl_driver_unregister); + +/** + * ishtp_bus_event_work() - event work function + * @work: work struct pointer + * + * Once an event is received for a client this work + * function is called. If the device has registered a + * callback then the callback is called. + */ +static void ishtp_bus_event_work(struct work_struct *work) +{ + struct ishtp_cl_device *device; + + device = container_of(work, struct ishtp_cl_device, event_work); + + if (device->event_cb) + device->event_cb(device); +} + +/** + * ishtp_cl_bus_rx_event() - schedule event work + * @device: client device instance + * + * Once an event is received for a client this schedules + * a work function to process. + */ +void ishtp_cl_bus_rx_event(struct ishtp_cl_device *device) +{ + if (!device || !device->event_cb) + return; + + if (device->event_cb) + schedule_work(&device->event_work); +} + +/** + * ishtp_register_event_cb() - Register callback + * @device: client device instance + * @event_cb: Event processor for an client + * + * Register a callback for events, called from client driver + * + * Return: Return 0 or -EALREADY if already registered + */ +int ishtp_register_event_cb(struct ishtp_cl_device *device, + void (*event_cb)(struct ishtp_cl_device *)) +{ + if (device->event_cb) + return -EALREADY; + + device->event_cb = event_cb; + INIT_WORK(&device->event_work, ishtp_bus_event_work); + + return 0; +} +EXPORT_SYMBOL(ishtp_register_event_cb); + +/** + * ishtp_get_device() - update usage count for the device + * @cl_device: client device instance + * + * Increment the usage count. The device can't be deleted + */ +void ishtp_get_device(struct ishtp_cl_device *cl_device) +{ + cl_device->reference_count++; +} +EXPORT_SYMBOL(ishtp_get_device); + +/** + * ishtp_put_device() - decrement usage count for the device + * @cl_device: client device instance + * + * Decrement the usage count. The device can be deleted is count = 0 + */ +void ishtp_put_device(struct ishtp_cl_device *cl_device) +{ + cl_device->reference_count--; +} +EXPORT_SYMBOL(ishtp_put_device); + +/** + * ishtp_bus_new_client() - Create a new client + * @dev: ISHTP device instance + * + * Once bus protocol enumerates a client, this is called + * to add a device for the client. + * + * Return: 0 on success or error code on failure + */ +int ishtp_bus_new_client(struct ishtp_device *dev) +{ + int i; + char *dev_name; + struct ishtp_cl_device *cl_device; + uuid_le device_uuid; + + /* + * For all reported clients, create an unconnected client and add its + * device to ISHTP bus. + * If appropriate driver has loaded, this will trigger its probe(). + * Otherwise, probe() will be called when driver is loaded + */ + i = dev->fw_client_presentation_num - 1; + device_uuid = dev->fw_clients[i].props.protocol_name; + dev_name = kasprintf(GFP_KERNEL, "{%pUL}", device_uuid.b); + if (!dev_name) + return -ENOMEM; + + cl_device = ishtp_bus_add_device(dev, device_uuid, dev_name); + if (!cl_device) { + kfree(dev_name); + return -ENOENT; + } + + kfree(dev_name); + + return 0; +} + +/** + * ishtp_cl_device_bind() - bind a device + * @cl: ishtp client device + * + * Binds connected ishtp_cl to ISHTP bus device + * + * Return: 0 on success or fault code + */ +int ishtp_cl_device_bind(struct ishtp_cl *cl) +{ + struct ishtp_cl_device *cl_device; + unsigned long flags; + int rv; + + if (!cl->fw_client_id || cl->state != ISHTP_CL_CONNECTED) + return -EFAULT; + + rv = -ENOENT; + spin_lock_irqsave(&cl->dev->device_list_lock, flags); + list_for_each_entry(cl_device, &cl->dev->device_list, + device_link) { + if (cl_device->fw_client && + cl_device->fw_client->client_id == cl->fw_client_id) { + cl->device = cl_device; + rv = 0; + break; + } + } + spin_unlock_irqrestore(&cl->dev->device_list_lock, flags); + return rv; +} + +/** + * ishtp_bus_remove_all_clients() - Remove all clients + * @ishtp_dev: ishtp device + * @warm_reset: Reset due to FW reset dure to errors or S3 suspend + * + * This is part of reset/remove flow. This function the main processing + * only targets error processing, if the FW has forced reset or + * error to remove connected clients. When warm reset the client devices are + * not removed. + */ +void ishtp_bus_remove_all_clients(struct ishtp_device *ishtp_dev, + bool warm_reset) +{ + struct ishtp_cl_device *cl_device, *n; + struct ishtp_cl *cl; + unsigned long flags; + + spin_lock_irqsave(&ishtp_dev->cl_list_lock, flags); + list_for_each_entry(cl, &ishtp_dev->cl_list, link) { + cl->state = ISHTP_CL_DISCONNECTED; + + /* + * Wake any pending process. The waiter would check dev->state + * and determine that it's not enabled already, + * and will return error to its caller + */ + wake_up_interruptible(&cl->wait_ctrl_res); + + /* Disband any pending read/write requests and free rb */ + ishtp_cl_flush_queues(cl); + + /* Remove all free and in_process rings, both Rx and Tx */ + ishtp_cl_free_rx_ring(cl); + ishtp_cl_free_tx_ring(cl); + + /* + * Free client and ISHTP bus client device structures + * don't free host client because it is part of the OS fd + * structure + */ + } + spin_unlock_irqrestore(&ishtp_dev->cl_list_lock, flags); + + /* Release DMA buffers for client messages */ + ishtp_cl_free_dma_buf(ishtp_dev); + + /* remove bus clients */ + spin_lock_irqsave(&ishtp_dev->device_list_lock, flags); + list_for_each_entry_safe(cl_device, n, &ishtp_dev->device_list, + device_link) { + cl_device->fw_client = NULL; + if (warm_reset && cl_device->reference_count) + continue; + + list_del(&cl_device->device_link); + spin_unlock_irqrestore(&ishtp_dev->device_list_lock, flags); + ishtp_bus_remove_device(cl_device); + spin_lock_irqsave(&ishtp_dev->device_list_lock, flags); + } + spin_unlock_irqrestore(&ishtp_dev->device_list_lock, flags); + + /* Free all client structures */ + spin_lock_irqsave(&ishtp_dev->fw_clients_lock, flags); + kfree(ishtp_dev->fw_clients); + ishtp_dev->fw_clients = NULL; + ishtp_dev->fw_clients_num = 0; + ishtp_dev->fw_client_presentation_num = 0; + ishtp_dev->fw_client_index = 0; + bitmap_zero(ishtp_dev->fw_clients_map, ISHTP_CLIENTS_MAX); + spin_unlock_irqrestore(&ishtp_dev->fw_clients_lock, flags); +} +EXPORT_SYMBOL(ishtp_bus_remove_all_clients); + +/** + * ishtp_reset_handler() - IPC reset handler + * @dev: ishtp device + * + * ISHTP Handler for IPC_RESET notification + */ +void ishtp_reset_handler(struct ishtp_device *dev) +{ + unsigned long flags; + + /* Handle FW-initiated reset */ + dev->dev_state = ISHTP_DEV_RESETTING; + + /* Clear BH processing queue - no further HBMs */ + spin_lock_irqsave(&dev->rd_msg_spinlock, flags); + dev->rd_msg_fifo_head = dev->rd_msg_fifo_tail = 0; + spin_unlock_irqrestore(&dev->rd_msg_spinlock, flags); + + /* Handle ISH FW reset against upper layers */ + ishtp_bus_remove_all_clients(dev, true); +} +EXPORT_SYMBOL(ishtp_reset_handler); + +/** + * ishtp_reset_compl_handler() - Reset completion handler + * @dev: ishtp device + * + * ISHTP handler for IPC_RESET sequence completion to start + * host message bus start protocol sequence. + */ +void ishtp_reset_compl_handler(struct ishtp_device *dev) +{ + dev->dev_state = ISHTP_DEV_INIT_CLIENTS; + dev->hbm_state = ISHTP_HBM_START; + ishtp_hbm_start_req(dev); +} +EXPORT_SYMBOL(ishtp_reset_compl_handler); + +/** + * ishtp_use_dma_transfer() - Function to use DMA + * + * This interface is used to enable usage of DMA + * + * Return non zero if DMA can be enabled + */ +int ishtp_use_dma_transfer(void) +{ + return ishtp_use_dma; +} + +/** + * ishtp_bus_register() - Function to register bus + * + * This register ishtp bus + * + * Return: Return output of bus_register + */ +static int __init ishtp_bus_register(void) +{ + return bus_register(&ishtp_cl_bus_type); +} + +/** + * ishtp_bus_unregister() - Function to unregister bus + * + * This unregister ishtp bus + */ +static void __exit ishtp_bus_unregister(void) +{ + bus_unregister(&ishtp_cl_bus_type); +} + +module_init(ishtp_bus_register); +module_exit(ishtp_bus_unregister); + +MODULE_LICENSE("GPL"); |