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_cl_is_transitioning(cl))) {
268 if (signal_pending(current))
273 mutex_lock(&dev->device_lock);
274 if (mei_cl_is_transitioning(cl)) {
286 if (cl->reading_state != MEI_READ_COMPLETE) {
290 /* now copy the data to user space */
292 dev_dbg(&dev->pdev->dev, "buf.size = %d buf.idx= %ld\n",
293 cb->response_buffer.size, cb->buf_idx);
294 if (length == 0 || ubuf == NULL || *offset > cb->buf_idx) {
299 /* length is being truncated to PAGE_SIZE,
300 * however buf_idx may point beyond that */
301 length = min_t(size_t, length, cb->buf_idx - *offset);
303 if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length)) {
310 if ((unsigned long)*offset < cb->buf_idx)
314 cb_pos = mei_cl_find_read_cb(cl);
315 /* Remove entry from read list */
317 list_del(&cb_pos->list);
319 cl->reading_state = MEI_IDLE;
322 dev_dbg(&dev->pdev->dev, "end mei read rets= %d\n", rets);
323 mutex_unlock(&dev->device_lock);
327 * mei_write - the write function.
329 * @file: pointer to file structure
330 * @ubuf: pointer to user buffer
331 * @length: buffer length
332 * @offset: data offset in buffer
334 * returns >=0 data length on success , <0 on error
336 static ssize_t mei_write(struct file *file, const char __user *ubuf,
337 size_t length, loff_t *offset)
339 struct mei_cl *cl = file->private_data;
340 struct mei_cl_cb *write_cb = NULL;
341 struct mei_device *dev;
342 unsigned long timeout = 0;
346 if (WARN_ON(!cl || !cl->dev))
351 mutex_lock(&dev->device_lock);
353 if (dev->dev_state != MEI_DEV_ENABLED) {
358 id = mei_me_cl_by_id(dev, cl->me_client_id);
363 if (length > dev->me_clients[id].props.max_msg_length || length <= 0) {
368 if (cl->state != MEI_FILE_CONNECTED) {
369 dev_err(&dev->pdev->dev, "host client = %d, is not connected to ME client = %d",
370 cl->host_client_id, cl->me_client_id);
374 if (cl == &dev->iamthif_cl) {
375 write_cb = mei_amthif_find_read_list_entry(dev, file);
378 timeout = write_cb->read_time +
379 mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
381 if (time_after(jiffies, timeout) ||
382 cl->reading_state == MEI_READ_COMPLETE) {
384 list_del(&write_cb->list);
385 mei_io_cb_free(write_cb);
391 /* free entry used in read */
392 if (cl->reading_state == MEI_READ_COMPLETE) {
394 write_cb = mei_cl_find_read_cb(cl);
396 list_del(&write_cb->list);
397 mei_io_cb_free(write_cb);
399 cl->reading_state = MEI_IDLE;
402 } else if (cl->reading_state == MEI_IDLE)
406 write_cb = mei_io_cb_init(cl, file);
408 dev_err(&dev->pdev->dev, "write cb allocation failed\n");
412 rets = mei_io_cb_alloc_req_buf(write_cb, length);
416 rets = copy_from_user(write_cb->request_buffer.data, ubuf, length);
422 ((memcmp(mei_wd_state_independence_msg[0],
423 write_cb->request_buffer.data, 4) == 0) ||
424 (memcmp(mei_wd_state_independence_msg[1],
425 write_cb->request_buffer.data, 4) == 0) ||
426 (memcmp(mei_wd_state_independence_msg[2],
427 write_cb->request_buffer.data, 4) == 0)))
428 cl->sm_state |= MEI_WD_STATE_INDEPENDENCE_MSG_SENT;
430 if (cl == &dev->iamthif_cl) {
431 rets = mei_amthif_write(dev, write_cb);
434 dev_err(&dev->pdev->dev,
435 "amthif write failed with status = %d\n", rets);
438 mutex_unlock(&dev->device_lock);
442 rets = mei_cl_write(cl, write_cb, false);
444 mutex_unlock(&dev->device_lock);
446 mei_io_cb_free(write_cb);
451 * mei_ioctl_connect_client - the connect to fw client IOCTL function
453 * @dev: the device structure
454 * @data: IOCTL connect data, input and output parameters
455 * @file: private data of the file object
457 * Locking: called under "dev->device_lock" lock
459 * returns 0 on success, <0 on failure.
461 static int mei_ioctl_connect_client(struct file *file,
462 struct mei_connect_client_data *data)
464 struct mei_device *dev;
465 struct mei_client *client;
470 cl = file->private_data;
471 if (WARN_ON(!cl || !cl->dev))
476 if (dev->dev_state != MEI_DEV_ENABLED) {
481 if (cl->state != MEI_FILE_INITIALIZING &&
482 cl->state != MEI_FILE_DISCONNECTED) {
487 /* find ME client we're trying to connect to */
488 i = mei_me_cl_by_uuid(dev, &data->in_client_uuid);
489 if (i < 0 || dev->me_clients[i].props.fixed_address) {
490 dev_dbg(&dev->pdev->dev, "Cannot connect to FW Client UUID = %pUl\n",
491 &data->in_client_uuid);
496 cl->me_client_id = dev->me_clients[i].client_id;
497 cl->state = MEI_FILE_CONNECTING;
499 dev_dbg(&dev->pdev->dev, "Connect to FW Client ID = %d\n",
501 dev_dbg(&dev->pdev->dev, "FW Client - Protocol Version = %d\n",
502 dev->me_clients[i].props.protocol_version);
503 dev_dbg(&dev->pdev->dev, "FW Client - Max Msg Len = %d\n",
504 dev->me_clients[i].props.max_msg_length);
506 /* if we're connecting to amthif client then we will use the
507 * existing connection
509 if (uuid_le_cmp(data->in_client_uuid, mei_amthif_guid) == 0) {
510 dev_dbg(&dev->pdev->dev, "FW Client is amthi\n");
511 if (dev->iamthif_cl.state != MEI_FILE_CONNECTED) {
515 clear_bit(cl->host_client_id, dev->host_clients_map);
520 file->private_data = &dev->iamthif_cl;
522 client = &data->out_client_properties;
523 client->max_msg_length =
524 dev->me_clients[i].props.max_msg_length;
525 client->protocol_version =
526 dev->me_clients[i].props.protocol_version;
527 rets = dev->iamthif_cl.status;
533 /* prepare the output buffer */
534 client = &data->out_client_properties;
535 client->max_msg_length = dev->me_clients[i].props.max_msg_length;
536 client->protocol_version = dev->me_clients[i].props.protocol_version;
537 dev_dbg(&dev->pdev->dev, "Can connect?\n");
540 rets = mei_cl_connect(cl, file);
548 * mei_ioctl - the IOCTL function
550 * @file: pointer to file structure
551 * @cmd: ioctl command
552 * @data: pointer to mei message structure
554 * returns 0 on success , <0 on error
556 static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data)
558 struct mei_device *dev;
559 struct mei_cl *cl = file->private_data;
560 struct mei_connect_client_data *connect_data = NULL;
563 if (cmd != IOCTL_MEI_CONNECT_CLIENT)
566 if (WARN_ON(!cl || !cl->dev))
571 dev_dbg(&dev->pdev->dev, "IOCTL cmd = 0x%x", cmd);
573 mutex_lock(&dev->device_lock);
574 if (dev->dev_state != MEI_DEV_ENABLED) {
579 dev_dbg(&dev->pdev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n");
581 connect_data = kzalloc(sizeof(struct mei_connect_client_data),
587 dev_dbg(&dev->pdev->dev, "copy connect data from user\n");
588 if (copy_from_user(connect_data, (char __user *)data,
589 sizeof(struct mei_connect_client_data))) {
590 dev_dbg(&dev->pdev->dev, "failed to copy data from userland\n");
595 rets = mei_ioctl_connect_client(file, connect_data);
597 /* if all is ok, copying the data back to user. */
601 dev_dbg(&dev->pdev->dev, "copy connect data to user\n");
602 if (copy_to_user((char __user *)data, connect_data,
603 sizeof(struct mei_connect_client_data))) {
604 dev_dbg(&dev->pdev->dev, "failed to copy data to userland\n");
611 mutex_unlock(&dev->device_lock);
616 * mei_compat_ioctl - the compat IOCTL function
618 * @file: pointer to file structure
619 * @cmd: ioctl command
620 * @data: pointer to mei message structure
622 * returns 0 on success , <0 on error
625 static long mei_compat_ioctl(struct file *file,
626 unsigned int cmd, unsigned long data)
628 return mei_ioctl(file, cmd, (unsigned long)compat_ptr(data));
634 * mei_poll - the poll function
636 * @file: pointer to file structure
637 * @wait: pointer to poll_table structure
641 static unsigned int mei_poll(struct file *file, poll_table *wait)
643 struct mei_cl *cl = file->private_data;
644 struct mei_device *dev;
645 unsigned int mask = 0;
647 if (WARN_ON(!cl || !cl->dev))
652 mutex_lock(&dev->device_lock);
654 if (dev->dev_state != MEI_DEV_ENABLED)
658 if (cl == &dev->iamthif_cl) {
659 mask = mei_amthif_poll(dev, file, wait);
663 mutex_unlock(&dev->device_lock);
664 poll_wait(file, &cl->tx_wait, wait);
665 mutex_lock(&dev->device_lock);
666 if (MEI_WRITE_COMPLETE == cl->writing_state)
667 mask |= (POLLIN | POLLRDNORM);
670 mutex_unlock(&dev->device_lock);
675 * file operations structure will be used for mei char device.
677 static const struct file_operations mei_fops = {
678 .owner = THIS_MODULE,
680 .unlocked_ioctl = mei_ioctl,
682 .compat_ioctl = mei_compat_ioctl,
685 .release = mei_release,
694 static struct miscdevice mei_misc_device = {
697 .minor = MISC_DYNAMIC_MINOR,
701 int mei_register(struct mei_device *dev)
704 mei_misc_device.parent = &dev->pdev->dev;
705 ret = misc_register(&mei_misc_device);
709 if (mei_dbgfs_register(dev, mei_misc_device.name))
710 dev_err(&dev->pdev->dev, "cannot register debugfs\n");
714 EXPORT_SYMBOL_GPL(mei_register);
716 void mei_deregister(struct mei_device *dev)
718 mei_dbgfs_deregister(dev);
719 misc_deregister(&mei_misc_device);
720 mei_misc_device.parent = NULL;
722 EXPORT_SYMBOL_GPL(mei_deregister);
724 static int __init mei_init(void)
726 return mei_cl_bus_init();
729 static void __exit mei_exit(void)
734 module_init(mei_init);
735 module_exit(mei_exit);
737 MODULE_AUTHOR("Intel Corporation");
738 MODULE_DESCRIPTION("Intel(R) Management Engine Interface");
739 MODULE_LICENSE("GPL v2");