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
16 #include <linux/module.h>
17 #include <linux/moduleparam.h>
18 #include <linux/kernel.h>
19 #include <linux/device.h>
21 #include <linux/errno.h>
22 #include <linux/types.h>
23 #include <linux/fcntl.h>
24 #include <linux/aio.h>
25 #include <linux/pci.h>
26 #include <linux/poll.h>
27 #include <linux/init.h>
28 #include <linux/ioctl.h>
29 #include <linux/cdev.h>
30 #include <linux/sched.h>
31 #include <linux/uuid.h>
32 #include <linux/compat.h>
33 #include <linux/jiffies.h>
34 #include <linux/interrupt.h>
35 #include <linux/miscdevice.h>
37 #include <linux/mei.h>
43 * mei_open - the open function
45 * @inode: pointer to inode structure
46 * @file: pointer to file structure
48 * returns 0 on success, <0 on error
50 static int mei_open(struct inode *inode, struct file *file)
52 struct miscdevice *misc = file->private_data;
55 struct mei_device *dev;
62 pdev = container_of(misc->parent, struct pci_dev, dev);
64 dev = pci_get_drvdata(pdev);
68 mutex_lock(&dev->device_lock);
73 if (dev->dev_state != MEI_DEV_ENABLED) {
74 dev_dbg(&dev->pdev->dev, "dev_state != MEI_ENABLED dev_state = %s\n",
75 mei_dev_state_str(dev->dev_state));
80 cl = mei_cl_allocate(dev);
84 /* open_handle_count check is handled in the mei_cl_link */
85 err = mei_cl_link(cl, MEI_HOST_CLIENT_ID_ANY);
89 file->private_data = cl;
91 mutex_unlock(&dev->device_lock);
93 return nonseekable_open(inode, file);
96 mutex_unlock(&dev->device_lock);
102 * mei_release - the release function
104 * @inode: pointer to inode structure
105 * @file: pointer to file structure
107 * returns 0 on success, <0 on error
109 static int mei_release(struct inode *inode, struct file *file)
111 struct mei_cl *cl = file->private_data;
112 struct mei_cl_cb *cb;
113 struct mei_device *dev;
116 if (WARN_ON(!cl || !cl->dev))
121 mutex_lock(&dev->device_lock);
122 if (cl == &dev->iamthif_cl) {
123 rets = mei_amthif_release(dev, file);
126 if (cl->state == MEI_FILE_CONNECTED) {
127 cl->state = MEI_FILE_DISCONNECTING;
128 dev_dbg(&dev->pdev->dev,
129 "disconnecting client host client = %d, "
133 rets = mei_cl_disconnect(cl);
135 mei_cl_flush_queues(cl);
136 dev_dbg(&dev->pdev->dev, "remove client host client = %d, ME client = %d\n",
146 cb = mei_cl_find_read_cb(cl);
147 /* Remove entry from read list */
155 file->private_data = NULL;
161 mutex_unlock(&dev->device_lock);
167 * mei_read - the read function.
169 * @file: pointer to file structure
170 * @ubuf: pointer to user buffer
171 * @length: buffer length
172 * @offset: data offset in buffer
174 * returns >=0 data length on success , <0 on error
176 static ssize_t mei_read(struct file *file, char __user *ubuf,
177 size_t length, loff_t *offset)
179 struct mei_cl *cl = file->private_data;
180 struct mei_cl_cb *cb_pos = NULL;
181 struct mei_cl_cb *cb = NULL;
182 struct mei_device *dev;
187 if (WARN_ON(!cl || !cl->dev))
193 mutex_lock(&dev->device_lock);
194 if (dev->dev_state != MEI_DEV_ENABLED) {
204 if (cl == &dev->iamthif_cl) {
205 rets = mei_amthif_read(dev, file, ubuf, length, offset);
212 if (cb->buf_idx > *offset)
214 /* offset is beyond buf_idx we have no more data return 0 */
215 if (cb->buf_idx > 0 && cb->buf_idx <= *offset) {
219 /* Offset needs to be cleaned for contiguous reads*/
220 if (cb->buf_idx == 0 && *offset > 0)
222 } else if (*offset > 0) {
226 err = mei_cl_read_start(cl, length);
227 if (err && err != -EBUSY) {
228 dev_dbg(&dev->pdev->dev,
229 "mei start read failure with status = %d\n", err);
234 if (MEI_READ_COMPLETE != cl->reading_state &&
235 !waitqueue_active(&cl->rx_wait)) {
236 if (file->f_flags & O_NONBLOCK) {
241 mutex_unlock(&dev->device_lock);
243 if (wait_event_interruptible(cl->rx_wait,
244 MEI_READ_COMPLETE == cl->reading_state ||
245 mei_cl_is_transitioning(cl))) {
247 if (signal_pending(current))
252 mutex_lock(&dev->device_lock);
253 if (mei_cl_is_transitioning(cl)) {
265 if (cl->reading_state != MEI_READ_COMPLETE) {
269 /* now copy the data to user space */
271 dev_dbg(&dev->pdev->dev, "buf.size = %d buf.idx= %ld\n",
272 cb->response_buffer.size, cb->buf_idx);
273 if (length == 0 || ubuf == NULL || *offset > cb->buf_idx) {
278 /* length is being truncated to PAGE_SIZE,
279 * however buf_idx may point beyond that */
280 length = min_t(size_t, length, cb->buf_idx - *offset);
282 if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length)) {
289 if ((unsigned long)*offset < cb->buf_idx)
293 cb_pos = mei_cl_find_read_cb(cl);
294 /* Remove entry from read list */
296 list_del(&cb_pos->list);
298 cl->reading_state = MEI_IDLE;
301 dev_dbg(&dev->pdev->dev, "end mei read rets= %d\n", rets);
302 mutex_unlock(&dev->device_lock);
306 * mei_write - the write function.
308 * @file: pointer to file structure
309 * @ubuf: pointer to user buffer
310 * @length: buffer length
311 * @offset: data offset in buffer
313 * returns >=0 data length on success , <0 on error
315 static ssize_t mei_write(struct file *file, const char __user *ubuf,
316 size_t length, loff_t *offset)
318 struct mei_cl *cl = file->private_data;
319 struct mei_cl_cb *write_cb = NULL;
320 struct mei_device *dev;
321 unsigned long timeout = 0;
325 if (WARN_ON(!cl || !cl->dev))
330 mutex_lock(&dev->device_lock);
332 if (dev->dev_state != MEI_DEV_ENABLED) {
337 id = mei_me_cl_by_id(dev, cl->me_client_id);
348 if (length > dev->me_clients[id].props.max_msg_length) {
353 if (cl->state != MEI_FILE_CONNECTED) {
354 dev_err(&dev->pdev->dev, "host client = %d, is not connected to ME client = %d",
355 cl->host_client_id, cl->me_client_id);
359 if (cl == &dev->iamthif_cl) {
360 write_cb = mei_amthif_find_read_list_entry(dev, file);
363 timeout = write_cb->read_time +
364 mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
366 if (time_after(jiffies, timeout) ||
367 cl->reading_state == MEI_READ_COMPLETE) {
369 list_del(&write_cb->list);
370 mei_io_cb_free(write_cb);
376 /* free entry used in read */
377 if (cl->reading_state == MEI_READ_COMPLETE) {
379 write_cb = mei_cl_find_read_cb(cl);
381 list_del(&write_cb->list);
382 mei_io_cb_free(write_cb);
384 cl->reading_state = MEI_IDLE;
387 } else if (cl->reading_state == MEI_IDLE)
391 write_cb = mei_io_cb_init(cl, file);
393 dev_err(&dev->pdev->dev, "write cb allocation failed\n");
397 rets = mei_io_cb_alloc_req_buf(write_cb, length);
401 rets = copy_from_user(write_cb->request_buffer.data, ubuf, length);
403 dev_err(&dev->pdev->dev, "failed to copy data from userland\n");
408 if (cl == &dev->iamthif_cl) {
409 rets = mei_amthif_write(dev, write_cb);
412 dev_err(&dev->pdev->dev,
413 "amthif write failed with status = %d\n", rets);
416 mutex_unlock(&dev->device_lock);
420 rets = mei_cl_write(cl, write_cb, false);
422 mutex_unlock(&dev->device_lock);
424 mei_io_cb_free(write_cb);
429 * mei_ioctl_connect_client - the connect to fw client IOCTL function
431 * @dev: the device structure
432 * @data: IOCTL connect data, input and output parameters
433 * @file: private data of the file object
435 * Locking: called under "dev->device_lock" lock
437 * returns 0 on success, <0 on failure.
439 static int mei_ioctl_connect_client(struct file *file,
440 struct mei_connect_client_data *data)
442 struct mei_device *dev;
443 struct mei_client *client;
448 cl = file->private_data;
449 if (WARN_ON(!cl || !cl->dev))
454 if (dev->dev_state != MEI_DEV_ENABLED) {
459 if (cl->state != MEI_FILE_INITIALIZING &&
460 cl->state != MEI_FILE_DISCONNECTED) {
465 /* find ME client we're trying to connect to */
466 i = mei_me_cl_by_uuid(dev, &data->in_client_uuid);
467 if (i < 0 || dev->me_clients[i].props.fixed_address) {
468 dev_dbg(&dev->pdev->dev, "Cannot connect to FW Client UUID = %pUl\n",
469 &data->in_client_uuid);
474 cl->me_client_id = dev->me_clients[i].client_id;
475 cl->state = MEI_FILE_CONNECTING;
477 dev_dbg(&dev->pdev->dev, "Connect to FW Client ID = %d\n",
479 dev_dbg(&dev->pdev->dev, "FW Client - Protocol Version = %d\n",
480 dev->me_clients[i].props.protocol_version);
481 dev_dbg(&dev->pdev->dev, "FW Client - Max Msg Len = %d\n",
482 dev->me_clients[i].props.max_msg_length);
484 /* if we're connecting to amthif client then we will use the
485 * existing connection
487 if (uuid_le_cmp(data->in_client_uuid, mei_amthif_guid) == 0) {
488 dev_dbg(&dev->pdev->dev, "FW Client is amthi\n");
489 if (dev->iamthif_cl.state != MEI_FILE_CONNECTED) {
497 dev->iamthif_open_count++;
498 file->private_data = &dev->iamthif_cl;
500 client = &data->out_client_properties;
501 client->max_msg_length =
502 dev->me_clients[i].props.max_msg_length;
503 client->protocol_version =
504 dev->me_clients[i].props.protocol_version;
505 rets = dev->iamthif_cl.status;
511 /* prepare the output buffer */
512 client = &data->out_client_properties;
513 client->max_msg_length = dev->me_clients[i].props.max_msg_length;
514 client->protocol_version = dev->me_clients[i].props.protocol_version;
515 dev_dbg(&dev->pdev->dev, "Can connect?\n");
518 rets = mei_cl_connect(cl, file);
526 * mei_ioctl - the IOCTL function
528 * @file: pointer to file structure
529 * @cmd: ioctl command
530 * @data: pointer to mei message structure
532 * returns 0 on success , <0 on error
534 static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data)
536 struct mei_device *dev;
537 struct mei_cl *cl = file->private_data;
538 struct mei_connect_client_data *connect_data = NULL;
541 if (cmd != IOCTL_MEI_CONNECT_CLIENT)
544 if (WARN_ON(!cl || !cl->dev))
549 dev_dbg(&dev->pdev->dev, "IOCTL cmd = 0x%x", cmd);
551 mutex_lock(&dev->device_lock);
552 if (dev->dev_state != MEI_DEV_ENABLED) {
557 dev_dbg(&dev->pdev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n");
559 connect_data = kzalloc(sizeof(struct mei_connect_client_data),
565 dev_dbg(&dev->pdev->dev, "copy connect data from user\n");
566 if (copy_from_user(connect_data, (char __user *)data,
567 sizeof(struct mei_connect_client_data))) {
568 dev_err(&dev->pdev->dev, "failed to copy data from userland\n");
573 rets = mei_ioctl_connect_client(file, connect_data);
575 /* if all is ok, copying the data back to user. */
579 dev_dbg(&dev->pdev->dev, "copy connect data to user\n");
580 if (copy_to_user((char __user *)data, connect_data,
581 sizeof(struct mei_connect_client_data))) {
582 dev_dbg(&dev->pdev->dev, "failed to copy data to userland\n");
589 mutex_unlock(&dev->device_lock);
594 * mei_compat_ioctl - the compat IOCTL function
596 * @file: pointer to file structure
597 * @cmd: ioctl command
598 * @data: pointer to mei message structure
600 * returns 0 on success , <0 on error
603 static long mei_compat_ioctl(struct file *file,
604 unsigned int cmd, unsigned long data)
606 return mei_ioctl(file, cmd, (unsigned long)compat_ptr(data));
612 * mei_poll - the poll function
614 * @file: pointer to file structure
615 * @wait: pointer to poll_table structure
619 static unsigned int mei_poll(struct file *file, poll_table *wait)
621 struct mei_cl *cl = file->private_data;
622 struct mei_device *dev;
623 unsigned int mask = 0;
625 if (WARN_ON(!cl || !cl->dev))
630 mutex_lock(&dev->device_lock);
632 if (!mei_cl_is_connected(cl)) {
637 mutex_unlock(&dev->device_lock);
640 if (cl == &dev->iamthif_cl)
641 return mei_amthif_poll(dev, file, wait);
643 poll_wait(file, &cl->tx_wait, wait);
645 mutex_lock(&dev->device_lock);
647 if (!mei_cl_is_connected(cl)) {
652 if (MEI_WRITE_COMPLETE == cl->writing_state)
653 mask |= (POLLIN | POLLRDNORM);
656 mutex_unlock(&dev->device_lock);
661 * file operations structure will be used for mei char device.
663 static const struct file_operations mei_fops = {
664 .owner = THIS_MODULE,
666 .unlocked_ioctl = mei_ioctl,
668 .compat_ioctl = mei_compat_ioctl,
671 .release = mei_release,
680 static struct miscdevice mei_misc_device = {
683 .minor = MISC_DYNAMIC_MINOR,
687 int mei_register(struct mei_device *dev)
690 mei_misc_device.parent = &dev->pdev->dev;
691 ret = misc_register(&mei_misc_device);
695 if (mei_dbgfs_register(dev, mei_misc_device.name))
696 dev_err(&dev->pdev->dev, "cannot register debugfs\n");
700 EXPORT_SYMBOL_GPL(mei_register);
702 void mei_deregister(struct mei_device *dev)
704 mei_dbgfs_deregister(dev);
705 misc_deregister(&mei_misc_device);
706 mei_misc_device.parent = NULL;
708 EXPORT_SYMBOL_GPL(mei_deregister);
710 static int __init mei_init(void)
712 return mei_cl_bus_init();
715 static void __exit mei_exit(void)
720 module_init(mei_init);
721 module_exit(mei_exit);
723 MODULE_AUTHOR("Intel Corporation");
724 MODULE_DESCRIPTION("Intel(R) Management Engine Interface");
725 MODULE_LICENSE("GPL v2");