2 * Intel Management Engine Interface (Intel MEI) Linux driver
3 * Copyright (c) 2012-2013, Intel Corporation.
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
16 #include <linux/module.h>
17 #include <linux/device.h>
18 #include <linux/kernel.h>
19 #include <linux/sched.h>
20 #include <linux/init.h>
21 #include <linux/errno.h>
22 #include <linux/slab.h>
23 #include <linux/mutex.h>
24 #include <linux/interrupt.h>
25 #include <linux/pci.h>
26 #include <linux/mei_cl_bus.h>
32 #define to_mei_cl_driver(d) container_of(d, struct mei_cl_driver, driver)
33 #define to_mei_cl_device(d) container_of(d, struct mei_cl_device, dev)
35 static int mei_cl_device_match(struct device *dev, struct device_driver *drv)
37 struct mei_cl_device *device = to_mei_cl_device(dev);
38 struct mei_cl_driver *driver = to_mei_cl_driver(drv);
39 const struct mei_cl_device_id *id;
44 if (!driver || !driver->id_table)
47 id = driver->id_table;
50 if (!strcmp(dev_name(dev), id->name))
59 static int mei_cl_device_probe(struct device *dev)
61 struct mei_cl_device *device = to_mei_cl_device(dev);
62 struct mei_cl_driver *driver;
63 struct mei_cl_device_id id;
68 driver = to_mei_cl_driver(dev->driver);
69 if (!driver || !driver->probe)
72 dev_dbg(dev, "Device probe\n");
74 strncpy(id.name, dev_name(dev), MEI_CL_NAME_SIZE);
76 return driver->probe(device, &id);
79 static int mei_cl_device_remove(struct device *dev)
81 struct mei_cl_device *device = to_mei_cl_device(dev);
82 struct mei_cl_driver *driver;
84 if (!device || !dev->driver)
87 if (device->event_cb) {
88 device->event_cb = NULL;
89 cancel_work_sync(&device->event_work);
92 driver = to_mei_cl_driver(dev->driver);
93 if (!driver->remove) {
99 return driver->remove(device);
102 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
107 len = snprintf(buf, PAGE_SIZE, "mei:%s\n", dev_name(dev));
109 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
112 static struct device_attribute mei_cl_dev_attrs[] = {
117 static int mei_cl_uevent(struct device *dev, struct kobj_uevent_env *env)
119 if (add_uevent_var(env, "MODALIAS=mei:%s", dev_name(dev)))
125 static struct bus_type mei_cl_bus_type = {
127 .dev_attrs = mei_cl_dev_attrs,
128 .match = mei_cl_device_match,
129 .probe = mei_cl_device_probe,
130 .remove = mei_cl_device_remove,
131 .uevent = mei_cl_uevent,
134 static void mei_cl_dev_release(struct device *dev)
136 kfree(to_mei_cl_device(dev));
139 static struct device_type mei_cl_device_type = {
140 .release = mei_cl_dev_release,
143 static struct mei_cl *mei_bus_find_mei_cl_by_uuid(struct mei_device *dev,
146 struct mei_cl *cl, *next;
148 list_for_each_entry_safe(cl, next, &dev->device_list, device_link) {
149 if (!uuid_le_cmp(uuid, cl->device_uuid))
155 struct mei_cl_device *mei_cl_add_device(struct mei_device *dev,
156 uuid_le uuid, char *name,
157 struct mei_cl_ops *ops)
159 struct mei_cl_device *device;
163 cl = mei_bus_find_mei_cl_by_uuid(dev, uuid);
167 device = kzalloc(sizeof(struct mei_cl_device), GFP_KERNEL);
174 device->dev.parent = &dev->pdev->dev;
175 device->dev.bus = &mei_cl_bus_type;
176 device->dev.type = &mei_cl_device_type;
178 dev_set_name(&device->dev, "%s", name);
180 status = device_register(&device->dev);
182 dev_err(&dev->pdev->dev, "Failed to register MEI device\n");
189 dev_dbg(&device->dev, "client %s registered\n", name);
193 EXPORT_SYMBOL_GPL(mei_cl_add_device);
195 void mei_cl_remove_device(struct mei_cl_device *device)
197 device_unregister(&device->dev);
199 EXPORT_SYMBOL_GPL(mei_cl_remove_device);
201 int __mei_cl_driver_register(struct mei_cl_driver *driver, struct module *owner)
205 driver->driver.name = driver->name;
206 driver->driver.owner = owner;
207 driver->driver.bus = &mei_cl_bus_type;
209 err = driver_register(&driver->driver);
213 pr_debug("mei: driver [%s] registered\n", driver->driver.name);
217 EXPORT_SYMBOL_GPL(__mei_cl_driver_register);
219 void mei_cl_driver_unregister(struct mei_cl_driver *driver)
221 driver_unregister(&driver->driver);
223 pr_debug("mei: driver [%s] unregistered\n", driver->driver.name);
225 EXPORT_SYMBOL_GPL(mei_cl_driver_unregister);
227 static int ___mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
230 struct mei_device *dev;
231 struct mei_cl_cb *cb;
235 if (WARN_ON(!cl || !cl->dev))
240 if (cl->state != MEI_FILE_CONNECTED)
243 /* Check if we have an ME client device */
244 id = mei_me_cl_by_id(dev, cl->me_client_id);
248 if (length > dev->me_clients[id].props.max_msg_length)
251 cb = mei_io_cb_init(cl, NULL);
255 rets = mei_io_cb_alloc_req_buf(cb, length);
261 memcpy(cb->request_buffer.data, buf, length);
263 mutex_lock(&dev->device_lock);
265 rets = mei_cl_write(cl, cb, blocking);
267 mutex_unlock(&dev->device_lock);
274 int __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
276 struct mei_device *dev;
277 struct mei_cl_cb *cb;
281 if (WARN_ON(!cl || !cl->dev))
286 mutex_lock(&dev->device_lock);
289 err = mei_cl_read_start(cl, length);
291 mutex_unlock(&dev->device_lock);
296 if (cl->reading_state != MEI_READ_COMPLETE &&
297 !waitqueue_active(&cl->rx_wait)) {
298 mutex_unlock(&dev->device_lock);
300 if (wait_event_interruptible(cl->rx_wait,
301 (MEI_READ_COMPLETE == cl->reading_state))) {
302 if (signal_pending(current))
307 mutex_lock(&dev->device_lock);
312 if (cl->reading_state != MEI_READ_COMPLETE) {
317 r_length = min_t(size_t, length, cb->buf_idx);
319 memcpy(buf, cb->response_buffer.data, r_length);
322 cl->reading_state = MEI_IDLE;
326 mutex_unlock(&dev->device_lock);
331 inline int __mei_cl_async_send(struct mei_cl *cl, u8 *buf, size_t length)
333 return ___mei_cl_send(cl, buf, length, 0);
336 inline int __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length)
338 return ___mei_cl_send(cl, buf, length, 1);
341 int mei_cl_send(struct mei_cl_device *device, u8 *buf, size_t length)
343 struct mei_cl *cl = device->cl;
348 if (device->ops && device->ops->send)
349 return device->ops->send(device, buf, length);
351 return __mei_cl_send(cl, buf, length);
353 EXPORT_SYMBOL_GPL(mei_cl_send);
355 int mei_cl_recv(struct mei_cl_device *device, u8 *buf, size_t length)
357 struct mei_cl *cl = device->cl;
362 if (device->ops && device->ops->recv)
363 return device->ops->recv(device, buf, length);
365 return __mei_cl_recv(cl, buf, length);
367 EXPORT_SYMBOL_GPL(mei_cl_recv);
369 static void mei_bus_event_work(struct work_struct *work)
371 struct mei_cl_device *device;
373 device = container_of(work, struct mei_cl_device, event_work);
375 if (device->event_cb)
376 device->event_cb(device, device->events, device->event_context);
380 /* Prepare for the next read */
381 mei_cl_read_start(device->cl, 0);
384 int mei_cl_register_event_cb(struct mei_cl_device *device,
385 mei_cl_event_cb_t event_cb, void *context)
387 if (device->event_cb)
391 device->event_cb = event_cb;
392 device->event_context = context;
393 INIT_WORK(&device->event_work, mei_bus_event_work);
395 mei_cl_read_start(device->cl, 0);
399 EXPORT_SYMBOL_GPL(mei_cl_register_event_cb);
401 void *mei_cl_get_drvdata(const struct mei_cl_device *device)
403 return dev_get_drvdata(&device->dev);
405 EXPORT_SYMBOL_GPL(mei_cl_get_drvdata);
407 void mei_cl_set_drvdata(struct mei_cl_device *device, void *data)
409 dev_set_drvdata(&device->dev, data);
411 EXPORT_SYMBOL_GPL(mei_cl_set_drvdata);
413 int mei_cl_enable_device(struct mei_cl_device *device)
416 struct mei_device *dev;
417 struct mei_cl *cl = device->cl;
424 mutex_lock(&dev->device_lock);
426 cl->state = MEI_FILE_CONNECTING;
428 err = mei_cl_connect(cl, NULL);
430 mutex_unlock(&dev->device_lock);
431 dev_err(&dev->pdev->dev, "Could not connect to the ME client");
436 mutex_unlock(&dev->device_lock);
438 if (device->event_cb && !cl->read_cb)
439 mei_cl_read_start(device->cl, 0);
441 if (!device->ops || !device->ops->enable)
444 return device->ops->enable(device);
446 EXPORT_SYMBOL_GPL(mei_cl_enable_device);
448 int mei_cl_disable_device(struct mei_cl_device *device)
451 struct mei_device *dev;
452 struct mei_cl *cl = device->cl;
459 mutex_lock(&dev->device_lock);
461 if (cl->state != MEI_FILE_CONNECTED) {
462 mutex_unlock(&dev->device_lock);
463 dev_err(&dev->pdev->dev, "Already disconnected");
468 cl->state = MEI_FILE_DISCONNECTING;
470 err = mei_cl_disconnect(cl);
472 mutex_unlock(&dev->device_lock);
473 dev_err(&dev->pdev->dev,
474 "Could not disconnect from the ME client");
479 /* Flush queues and remove any pending read */
480 mei_cl_flush_queues(cl);
483 struct mei_cl_cb *cb = NULL;
485 cb = mei_cl_find_read_cb(cl);
486 /* Remove entry from read list */
499 device->event_cb = NULL;
501 mutex_unlock(&dev->device_lock);
503 if (!device->ops || !device->ops->disable)
506 return device->ops->disable(device);
508 EXPORT_SYMBOL_GPL(mei_cl_disable_device);
510 void mei_cl_bus_rx_event(struct mei_cl *cl)
512 struct mei_cl_device *device = cl->device;
514 if (!device || !device->event_cb)
517 set_bit(MEI_CL_EVENT_RX, &device->events);
519 schedule_work(&device->event_work);
522 int __init mei_cl_bus_init(void)
524 return bus_register(&mei_cl_bus_type);
527 void __exit mei_cl_bus_exit(void)
529 bus_unregister(&mei_cl_bus_type);