3 * Intel Management Engine Interface (Intel MEI) Linux driver
4 * Copyright (c) 2003-2012, Intel Corporation.
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
19 #include <linux/module.h>
20 #include <linux/moduleparam.h>
21 #include <linux/kernel.h>
22 #include <linux/device.h>
24 #include <linux/errno.h>
25 #include <linux/types.h>
26 #include <linux/fcntl.h>
27 #include <linux/aio.h>
28 #include <linux/pci.h>
29 #include <linux/poll.h>
30 #include <linux/init.h>
31 #include <linux/ioctl.h>
32 #include <linux/cdev.h>
33 #include <linux/sched.h>
34 #include <linux/uuid.h>
35 #include <linux/compat.h>
36 #include <linux/jiffies.h>
37 #include <linux/interrupt.h>
38 #include <linux/miscdevice.h>
40 #include <linux/mei.h>
47 * mei_open - the open function
49 * @inode: pointer to inode structure
50 * @file: pointer to file structure
52 * returns 0 on success, <0 on error
54 static int mei_open(struct inode *inode, struct file *file)
56 struct miscdevice *misc = file->private_data;
59 struct mei_device *dev;
67 pdev = container_of(misc->parent, struct pci_dev, dev);
69 dev = pci_get_drvdata(pdev);
73 mutex_lock(&dev->device_lock);
75 cl = mei_cl_allocate(dev);
80 if (dev->dev_state != MEI_DEV_ENABLED) {
81 dev_dbg(&dev->pdev->dev, "dev_state != MEI_ENABLED dev_state = %s\n",
82 mei_dev_state_str(dev->dev_state));
86 if (dev->open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
87 dev_err(&dev->pdev->dev, "open_handle_count exceded %d",
88 MEI_MAX_OPEN_HANDLE_COUNT);
92 err = mei_cl_link(cl, MEI_HOST_CLIENT_ID_ANY);
96 file->private_data = cl;
97 mutex_unlock(&dev->device_lock);
99 return nonseekable_open(inode, file);
102 mutex_unlock(&dev->device_lock);
109 * mei_release - the release function
111 * @inode: pointer to inode structure
112 * @file: pointer to file structure
114 * returns 0 on success, <0 on error
116 static int mei_release(struct inode *inode, struct file *file)
118 struct mei_cl *cl = file->private_data;
119 struct mei_cl_cb *cb;
120 struct mei_device *dev;
123 if (WARN_ON(!cl || !cl->dev))
128 mutex_lock(&dev->device_lock);
129 if (cl == &dev->iamthif_cl) {
130 rets = mei_amthif_release(dev, file);
133 if (cl->state == MEI_FILE_CONNECTED) {
134 cl->state = MEI_FILE_DISCONNECTING;
135 dev_dbg(&dev->pdev->dev,
136 "disconnecting client host client = %d, "
140 rets = mei_cl_disconnect(cl);
142 mei_cl_flush_queues(cl);
143 dev_dbg(&dev->pdev->dev, "remove client host client = %d, ME client = %d\n",
147 if (dev->open_handle_count > 0) {
148 clear_bit(cl->host_client_id, dev->host_clients_map);
149 dev->open_handle_count--;
157 cb = mei_cl_find_read_cb(cl);
158 /* Remove entry from read list */
166 file->private_data = NULL;
175 mutex_unlock(&dev->device_lock);
181 * mei_read - the read function.
183 * @file: pointer to file structure
184 * @ubuf: pointer to user buffer
185 * @length: buffer length
186 * @offset: data offset in buffer
188 * returns >=0 data length on success , <0 on error
190 static ssize_t mei_read(struct file *file, char __user *ubuf,
191 size_t length, loff_t *offset)
193 struct mei_cl *cl = file->private_data;
194 struct mei_cl_cb *cb_pos = NULL;
195 struct mei_cl_cb *cb = NULL;
196 struct mei_device *dev;
202 if (WARN_ON(!cl || !cl->dev))
207 mutex_lock(&dev->device_lock);
208 if (dev->dev_state != MEI_DEV_ENABLED) {
213 if ((cl->sm_state & MEI_WD_STATE_INDEPENDENCE_MSG_SENT) == 0) {
214 /* Do not allow to read watchdog client */
215 i = mei_me_cl_by_uuid(dev, &mei_wd_guid);
217 struct mei_me_client *me_client = &dev->me_clients[i];
218 if (cl->me_client_id == me_client->client_id) {
224 cl->sm_state &= ~MEI_WD_STATE_INDEPENDENCE_MSG_SENT;
227 if (cl == &dev->iamthif_cl) {
228 rets = mei_amthif_read(dev, file, ubuf, length, offset);
232 if (cl->read_cb && cl->read_cb->buf_idx > *offset) {
235 } else if (cl->read_cb && cl->read_cb->buf_idx > 0 &&
236 cl->read_cb->buf_idx <= *offset) {
240 } else if ((!cl->read_cb || !cl->read_cb->buf_idx) && *offset > 0) {
241 /*Offset needs to be cleaned for contiguous reads*/
247 err = mei_cl_read_start(cl, length);
248 if (err && err != -EBUSY) {
249 dev_dbg(&dev->pdev->dev,
250 "mei start read failure with status = %d\n", err);
255 if (MEI_READ_COMPLETE != cl->reading_state &&
256 !waitqueue_active(&cl->rx_wait)) {
257 if (file->f_flags & O_NONBLOCK) {
262 mutex_unlock(&dev->device_lock);
264 if (wait_event_interruptible(cl->rx_wait,
265 (MEI_READ_COMPLETE == cl->reading_state ||
266 MEI_FILE_INITIALIZING == cl->state ||
267 MEI_FILE_DISCONNECTED == cl->state ||
268 MEI_FILE_DISCONNECTING == cl->state))) {
269 if (signal_pending(current))
274 mutex_lock(&dev->device_lock);
275 if (MEI_FILE_INITIALIZING == cl->state ||
276 MEI_FILE_DISCONNECTED == cl->state ||
277 MEI_FILE_DISCONNECTING == cl->state) {
289 if (cl->reading_state != MEI_READ_COMPLETE) {
293 /* now copy the data to user space */
295 dev_dbg(&dev->pdev->dev, "buf.size = %d buf.idx= %ld\n",
296 cb->response_buffer.size, cb->buf_idx);
297 if (length == 0 || ubuf == NULL || *offset > cb->buf_idx) {
302 /* length is being truncated to PAGE_SIZE,
303 * however buf_idx may point beyond that */
304 length = min_t(size_t, length, cb->buf_idx - *offset);
306 if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length)) {
313 if ((unsigned long)*offset < cb->buf_idx)
317 cb_pos = mei_cl_find_read_cb(cl);
318 /* Remove entry from read list */
320 list_del(&cb_pos->list);
322 cl->reading_state = MEI_IDLE;
325 dev_dbg(&dev->pdev->dev, "end mei read rets= %d\n", rets);
326 mutex_unlock(&dev->device_lock);
330 * mei_write - the write function.
332 * @file: pointer to file structure
333 * @ubuf: pointer to user buffer
334 * @length: buffer length
335 * @offset: data offset in buffer
337 * returns >=0 data length on success , <0 on error
339 static ssize_t mei_write(struct file *file, const char __user *ubuf,
340 size_t length, loff_t *offset)
342 struct mei_cl *cl = file->private_data;
343 struct mei_cl_cb *write_cb = NULL;
344 struct mei_device *dev;
345 unsigned long timeout = 0;
349 if (WARN_ON(!cl || !cl->dev))
354 mutex_lock(&dev->device_lock);
356 if (dev->dev_state != MEI_DEV_ENABLED) {
361 id = mei_me_cl_by_id(dev, cl->me_client_id);
366 if (length > dev->me_clients[id].props.max_msg_length || length <= 0) {
371 if (cl->state != MEI_FILE_CONNECTED) {
372 dev_err(&dev->pdev->dev, "host client = %d, is not connected to ME client = %d",
373 cl->host_client_id, cl->me_client_id);
377 if (cl == &dev->iamthif_cl) {
378 write_cb = mei_amthif_find_read_list_entry(dev, file);
381 timeout = write_cb->read_time +
382 mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
384 if (time_after(jiffies, timeout) ||
385 cl->reading_state == MEI_READ_COMPLETE) {
387 list_del(&write_cb->list);
388 mei_io_cb_free(write_cb);
394 /* free entry used in read */
395 if (cl->reading_state == MEI_READ_COMPLETE) {
397 write_cb = mei_cl_find_read_cb(cl);
399 list_del(&write_cb->list);
400 mei_io_cb_free(write_cb);
402 cl->reading_state = MEI_IDLE;
405 } else if (cl->reading_state == MEI_IDLE)
409 write_cb = mei_io_cb_init(cl, file);
411 dev_err(&dev->pdev->dev, "write cb allocation failed\n");
415 rets = mei_io_cb_alloc_req_buf(write_cb, length);
419 rets = copy_from_user(write_cb->request_buffer.data, ubuf, length);
425 ((memcmp(mei_wd_state_independence_msg[0],
426 write_cb->request_buffer.data, 4) == 0) ||
427 (memcmp(mei_wd_state_independence_msg[1],
428 write_cb->request_buffer.data, 4) == 0) ||
429 (memcmp(mei_wd_state_independence_msg[2],
430 write_cb->request_buffer.data, 4) == 0)))
431 cl->sm_state |= MEI_WD_STATE_INDEPENDENCE_MSG_SENT;
433 if (cl == &dev->iamthif_cl) {
434 rets = mei_amthif_write(dev, write_cb);
437 dev_err(&dev->pdev->dev,
438 "amthif write failed with status = %d\n", rets);
441 mutex_unlock(&dev->device_lock);
445 rets = mei_cl_write(cl, write_cb, false);
447 mutex_unlock(&dev->device_lock);
449 mei_io_cb_free(write_cb);
454 * mei_ioctl_connect_client - the connect to fw client IOCTL function
456 * @dev: the device structure
457 * @data: IOCTL connect data, input and output parameters
458 * @file: private data of the file object
460 * Locking: called under "dev->device_lock" lock
462 * returns 0 on success, <0 on failure.
464 static int mei_ioctl_connect_client(struct file *file,
465 struct mei_connect_client_data *data)
467 struct mei_device *dev;
468 struct mei_client *client;
473 cl = file->private_data;
474 if (WARN_ON(!cl || !cl->dev))
479 if (dev->dev_state != MEI_DEV_ENABLED) {
484 if (cl->state != MEI_FILE_INITIALIZING &&
485 cl->state != MEI_FILE_DISCONNECTED) {
490 /* find ME client we're trying to connect to */
491 i = mei_me_cl_by_uuid(dev, &data->in_client_uuid);
492 if (i >= 0 && !dev->me_clients[i].props.fixed_address) {
493 cl->me_client_id = dev->me_clients[i].client_id;
494 cl->state = MEI_FILE_CONNECTING;
497 dev_dbg(&dev->pdev->dev, "Connect to FW Client ID = %d\n",
499 dev_dbg(&dev->pdev->dev, "FW Client - Protocol Version = %d\n",
500 dev->me_clients[i].props.protocol_version);
501 dev_dbg(&dev->pdev->dev, "FW Client - Max Msg Len = %d\n",
502 dev->me_clients[i].props.max_msg_length);
504 /* if we're connecting to amthif client then we will use the
505 * existing connection
507 if (uuid_le_cmp(data->in_client_uuid, mei_amthif_guid) == 0) {
508 dev_dbg(&dev->pdev->dev, "FW Client is amthi\n");
509 if (dev->iamthif_cl.state != MEI_FILE_CONNECTED) {
513 clear_bit(cl->host_client_id, dev->host_clients_map);
518 file->private_data = &dev->iamthif_cl;
520 client = &data->out_client_properties;
521 client->max_msg_length =
522 dev->me_clients[i].props.max_msg_length;
523 client->protocol_version =
524 dev->me_clients[i].props.protocol_version;
525 rets = dev->iamthif_cl.status;
530 if (cl->state != MEI_FILE_CONNECTING) {
536 /* prepare the output buffer */
537 client = &data->out_client_properties;
538 client->max_msg_length = dev->me_clients[i].props.max_msg_length;
539 client->protocol_version = dev->me_clients[i].props.protocol_version;
540 dev_dbg(&dev->pdev->dev, "Can connect?\n");
543 rets = mei_cl_connect(cl, file);
546 dev_dbg(&dev->pdev->dev, "free connect cb memory.");
552 * mei_ioctl - the IOCTL function
554 * @file: pointer to file structure
555 * @cmd: ioctl command
556 * @data: pointer to mei message structure
558 * returns 0 on success , <0 on error
560 static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data)
562 struct mei_device *dev;
563 struct mei_cl *cl = file->private_data;
564 struct mei_connect_client_data *connect_data = NULL;
567 if (cmd != IOCTL_MEI_CONNECT_CLIENT)
570 if (WARN_ON(!cl || !cl->dev))
575 dev_dbg(&dev->pdev->dev, "IOCTL cmd = 0x%x", cmd);
577 mutex_lock(&dev->device_lock);
578 if (dev->dev_state != MEI_DEV_ENABLED) {
583 dev_dbg(&dev->pdev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n");
585 connect_data = kzalloc(sizeof(struct mei_connect_client_data),
591 dev_dbg(&dev->pdev->dev, "copy connect data from user\n");
592 if (copy_from_user(connect_data, (char __user *)data,
593 sizeof(struct mei_connect_client_data))) {
594 dev_dbg(&dev->pdev->dev, "failed to copy data from userland\n");
599 rets = mei_ioctl_connect_client(file, connect_data);
601 /* if all is ok, copying the data back to user. */
605 dev_dbg(&dev->pdev->dev, "copy connect data to user\n");
606 if (copy_to_user((char __user *)data, connect_data,
607 sizeof(struct mei_connect_client_data))) {
608 dev_dbg(&dev->pdev->dev, "failed to copy data to userland\n");
615 mutex_unlock(&dev->device_lock);
620 * mei_compat_ioctl - the compat IOCTL function
622 * @file: pointer to file structure
623 * @cmd: ioctl command
624 * @data: pointer to mei message structure
626 * returns 0 on success , <0 on error
629 static long mei_compat_ioctl(struct file *file,
630 unsigned int cmd, unsigned long data)
632 return mei_ioctl(file, cmd, (unsigned long)compat_ptr(data));
638 * mei_poll - the poll function
640 * @file: pointer to file structure
641 * @wait: pointer to poll_table structure
645 static unsigned int mei_poll(struct file *file, poll_table *wait)
647 struct mei_cl *cl = file->private_data;
648 struct mei_device *dev;
649 unsigned int mask = 0;
651 if (WARN_ON(!cl || !cl->dev))
656 mutex_lock(&dev->device_lock);
658 if (dev->dev_state != MEI_DEV_ENABLED)
662 if (cl == &dev->iamthif_cl) {
663 mask = mei_amthif_poll(dev, file, wait);
667 mutex_unlock(&dev->device_lock);
668 poll_wait(file, &cl->tx_wait, wait);
669 mutex_lock(&dev->device_lock);
670 if (MEI_WRITE_COMPLETE == cl->writing_state)
671 mask |= (POLLIN | POLLRDNORM);
674 mutex_unlock(&dev->device_lock);
679 * file operations structure will be used for mei char device.
681 static const struct file_operations mei_fops = {
682 .owner = THIS_MODULE,
684 .unlocked_ioctl = mei_ioctl,
686 .compat_ioctl = mei_compat_ioctl,
689 .release = mei_release,
698 static struct miscdevice mei_misc_device = {
701 .minor = MISC_DYNAMIC_MINOR,
705 int mei_register(struct mei_device *dev)
708 mei_misc_device.parent = &dev->pdev->dev;
709 ret = misc_register(&mei_misc_device);
713 if (mei_dbgfs_register(dev, mei_misc_device.name))
714 dev_err(&dev->pdev->dev, "cannot register debugfs\n");
718 EXPORT_SYMBOL_GPL(mei_register);
720 void mei_deregister(struct mei_device *dev)
722 mei_dbgfs_deregister(dev);
723 misc_deregister(&mei_misc_device);
724 mei_misc_device.parent = NULL;
726 EXPORT_SYMBOL_GPL(mei_deregister);
728 static int __init mei_init(void)
730 return mei_cl_bus_init();
733 static void __exit mei_exit(void)
738 module_init(mei_init);
739 module_exit(mei_exit);
741 MODULE_AUTHOR("Intel Corporation");
742 MODULE_DESCRIPTION("Intel(R) Management Engine Interface");
743 MODULE_LICENSE("GPL v2");