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/mei_cl_bus.h>
30 #define to_mei_cl_driver(d) container_of(d, struct mei_cl_driver, driver)
31 #define to_mei_cl_device(d) container_of(d, struct mei_cl_device, dev)
33 static int mei_cl_device_match(struct device *dev, struct device_driver *drv)
35 struct mei_cl_device *device = to_mei_cl_device(dev);
36 struct mei_cl_driver *driver = to_mei_cl_driver(drv);
37 const struct mei_cl_device_id *id;
42 if (!driver || !driver->id_table)
45 id = driver->id_table;
48 if (!strncmp(dev_name(dev), id->name, sizeof(id->name)))
57 static int mei_cl_device_probe(struct device *dev)
59 struct mei_cl_device *device = to_mei_cl_device(dev);
60 struct mei_cl_driver *driver;
61 struct mei_cl_device_id id;
66 driver = to_mei_cl_driver(dev->driver);
67 if (!driver || !driver->probe)
70 dev_dbg(dev, "Device probe\n");
72 strlcpy(id.name, dev_name(dev), sizeof(id.name));
74 return driver->probe(device, &id);
77 static int mei_cl_device_remove(struct device *dev)
79 struct mei_cl_device *device = to_mei_cl_device(dev);
80 struct mei_cl_driver *driver;
82 if (!device || !dev->driver)
85 if (device->event_cb) {
86 device->event_cb = NULL;
87 cancel_work_sync(&device->event_work);
90 driver = to_mei_cl_driver(dev->driver);
91 if (!driver->remove) {
97 return driver->remove(device);
100 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
105 len = snprintf(buf, PAGE_SIZE, "mei:%s\n", dev_name(dev));
107 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
109 static DEVICE_ATTR_RO(modalias);
111 static struct attribute *mei_cl_dev_attrs[] = {
112 &dev_attr_modalias.attr,
115 ATTRIBUTE_GROUPS(mei_cl_dev);
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_groups = mei_cl_dev_groups,
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,
148 list_for_each_entry(cl, &dev->device_list, device_link) {
149 if (!uuid_le_cmp(uuid, cl->cl_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->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->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_me_client *me_cl;
232 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 me_cl = mei_me_cl_by_uuid_id(dev, &cl->cl_uuid, cl->me_client_id);
248 if (length > me_cl->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)) {
299 mutex_unlock(&dev->device_lock);
301 if (wait_event_interruptible(cl->rx_wait,
302 cl->reading_state == MEI_READ_COMPLETE ||
303 mei_cl_is_transitioning(cl))) {
305 if (signal_pending(current))
310 mutex_lock(&dev->device_lock);
315 if (cl->reading_state != MEI_READ_COMPLETE) {
320 r_length = min_t(size_t, length, cb->buf_idx);
322 memcpy(buf, cb->response_buffer.data, r_length);
325 cl->reading_state = MEI_IDLE;
329 mutex_unlock(&dev->device_lock);
334 inline int __mei_cl_async_send(struct mei_cl *cl, u8 *buf, size_t length)
336 return ___mei_cl_send(cl, buf, length, 0);
339 inline int __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length)
341 return ___mei_cl_send(cl, buf, length, 1);
344 int mei_cl_send(struct mei_cl_device *device, u8 *buf, size_t length)
346 struct mei_cl *cl = device->cl;
351 if (device->ops && device->ops->send)
352 return device->ops->send(device, buf, length);
354 return __mei_cl_send(cl, buf, length);
356 EXPORT_SYMBOL_GPL(mei_cl_send);
358 int mei_cl_recv(struct mei_cl_device *device, u8 *buf, size_t length)
360 struct mei_cl *cl = device->cl;
365 if (device->ops && device->ops->recv)
366 return device->ops->recv(device, buf, length);
368 return __mei_cl_recv(cl, buf, length);
370 EXPORT_SYMBOL_GPL(mei_cl_recv);
372 static void mei_bus_event_work(struct work_struct *work)
374 struct mei_cl_device *device;
376 device = container_of(work, struct mei_cl_device, event_work);
378 if (device->event_cb)
379 device->event_cb(device, device->events, device->event_context);
383 /* Prepare for the next read */
384 mei_cl_read_start(device->cl, 0);
387 int mei_cl_register_event_cb(struct mei_cl_device *device,
388 mei_cl_event_cb_t event_cb, void *context)
390 if (device->event_cb)
394 device->event_cb = event_cb;
395 device->event_context = context;
396 INIT_WORK(&device->event_work, mei_bus_event_work);
398 mei_cl_read_start(device->cl, 0);
402 EXPORT_SYMBOL_GPL(mei_cl_register_event_cb);
404 void *mei_cl_get_drvdata(const struct mei_cl_device *device)
406 return dev_get_drvdata(&device->dev);
408 EXPORT_SYMBOL_GPL(mei_cl_get_drvdata);
410 void mei_cl_set_drvdata(struct mei_cl_device *device, void *data)
412 dev_set_drvdata(&device->dev, data);
414 EXPORT_SYMBOL_GPL(mei_cl_set_drvdata);
416 int mei_cl_enable_device(struct mei_cl_device *device)
419 struct mei_device *dev;
420 struct mei_cl *cl = device->cl;
427 mutex_lock(&dev->device_lock);
429 err = mei_cl_connect(cl, NULL);
431 mutex_unlock(&dev->device_lock);
432 dev_err(dev->dev, "Could not connect to the ME client");
437 mutex_unlock(&dev->device_lock);
439 if (device->event_cb && !cl->read_cb)
440 mei_cl_read_start(device->cl, 0);
442 if (!device->ops || !device->ops->enable)
445 return device->ops->enable(device);
447 EXPORT_SYMBOL_GPL(mei_cl_enable_device);
449 int mei_cl_disable_device(struct mei_cl_device *device)
452 struct mei_device *dev;
453 struct mei_cl *cl = device->cl;
460 mutex_lock(&dev->device_lock);
462 if (cl->state != MEI_FILE_CONNECTED) {
463 mutex_unlock(&dev->device_lock);
464 dev_err(dev->dev, "Already disconnected");
469 cl->state = MEI_FILE_DISCONNECTING;
471 err = mei_cl_disconnect(cl);
473 mutex_unlock(&dev->device_lock);
475 "Could not disconnect from the ME client");
480 /* Flush queues and remove any pending read */
481 mei_cl_flush_queues(cl);
484 struct mei_cl_cb *cb = NULL;
486 cb = mei_cl_find_read_cb(cl);
487 /* Remove entry from read list */
500 device->event_cb = NULL;
502 mutex_unlock(&dev->device_lock);
504 if (!device->ops || !device->ops->disable)
507 return device->ops->disable(device);
509 EXPORT_SYMBOL_GPL(mei_cl_disable_device);
511 void mei_cl_bus_rx_event(struct mei_cl *cl)
513 struct mei_cl_device *device = cl->device;
515 if (!device || !device->event_cb)
518 set_bit(MEI_CL_EVENT_RX, &device->events);
520 schedule_work(&device->event_work);
523 void mei_cl_bus_remove_devices(struct mei_device *dev)
525 struct mei_cl *cl, *next;
527 mutex_lock(&dev->device_lock);
528 list_for_each_entry_safe(cl, next, &dev->device_list, device_link) {
530 mei_cl_remove_device(cl->device);
532 list_del(&cl->device_link);
536 mutex_unlock(&dev->device_lock);
539 int __init mei_cl_bus_init(void)
541 return bus_register(&mei_cl_bus_type);
544 void __exit mei_cl_bus_exit(void)
546 bus_unregister(&mei_cl_bus_type);