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
;
201 if (WARN_ON(!cl
|| !cl
->dev
))
206 mutex_lock(&dev
->device_lock
);
207 if (dev
->dev_state
!= MEI_DEV_ENABLED
) {
212 if (cl
== &dev
->iamthif_cl
) {
213 rets
= mei_amthif_read(dev
, file
, ubuf
, length
, offset
);
220 if (cb
->buf_idx
> *offset
)
222 /* offset is beyond buf_idx we have no more data return 0 */
223 if (cb
->buf_idx
> 0 && cb
->buf_idx
<= *offset
) {
227 /* Offset needs to be cleaned for contiguous reads*/
228 if (cb
->buf_idx
== 0 && *offset
> 0)
230 } else if (*offset
> 0) {
234 err
= mei_cl_read_start(cl
, length
);
235 if (err
&& err
!= -EBUSY
) {
236 dev_dbg(&dev
->pdev
->dev
,
237 "mei start read failure with status = %d\n", err
);
242 if (MEI_READ_COMPLETE
!= cl
->reading_state
&&
243 !waitqueue_active(&cl
->rx_wait
)) {
244 if (file
->f_flags
& O_NONBLOCK
) {
249 mutex_unlock(&dev
->device_lock
);
251 if (wait_event_interruptible(cl
->rx_wait
,
252 (MEI_READ_COMPLETE
== cl
->reading_state
||
253 MEI_FILE_INITIALIZING
== cl
->state
||
254 MEI_FILE_DISCONNECTED
== cl
->state
||
255 MEI_FILE_DISCONNECTING
== cl
->state
))) {
256 if (signal_pending(current
))
261 mutex_lock(&dev
->device_lock
);
262 if (MEI_FILE_INITIALIZING
== cl
->state
||
263 MEI_FILE_DISCONNECTED
== cl
->state
||
264 MEI_FILE_DISCONNECTING
== cl
->state
) {
276 if (cl
->reading_state
!= MEI_READ_COMPLETE
) {
280 /* now copy the data to user space */
282 dev_dbg(&dev
->pdev
->dev
, "buf.size = %d buf.idx= %ld\n",
283 cb
->response_buffer
.size
, cb
->buf_idx
);
284 if (length
== 0 || ubuf
== NULL
|| *offset
> cb
->buf_idx
) {
289 /* length is being truncated to PAGE_SIZE,
290 * however buf_idx may point beyond that */
291 length
= min_t(size_t, length
, cb
->buf_idx
- *offset
);
293 if (copy_to_user(ubuf
, cb
->response_buffer
.data
+ *offset
, length
)) {
300 if ((unsigned long)*offset
< cb
->buf_idx
)
304 cb_pos
= mei_cl_find_read_cb(cl
);
305 /* Remove entry from read list */
307 list_del(&cb_pos
->list
);
309 cl
->reading_state
= MEI_IDLE
;
312 dev_dbg(&dev
->pdev
->dev
, "end mei read rets= %d\n", rets
);
313 mutex_unlock(&dev
->device_lock
);
317 * mei_write - the write function.
319 * @file: pointer to file structure
320 * @ubuf: pointer to user buffer
321 * @length: buffer length
322 * @offset: data offset in buffer
324 * returns >=0 data length on success , <0 on error
326 static ssize_t
mei_write(struct file
*file
, const char __user
*ubuf
,
327 size_t length
, loff_t
*offset
)
329 struct mei_cl
*cl
= file
->private_data
;
330 struct mei_cl_cb
*write_cb
= NULL
;
331 struct mei_device
*dev
;
332 unsigned long timeout
= 0;
336 if (WARN_ON(!cl
|| !cl
->dev
))
341 mutex_lock(&dev
->device_lock
);
343 if (dev
->dev_state
!= MEI_DEV_ENABLED
) {
348 id
= mei_me_cl_by_id(dev
, cl
->me_client_id
);
353 if (length
> dev
->me_clients
[id
].props
.max_msg_length
|| length
<= 0) {
358 if (cl
->state
!= MEI_FILE_CONNECTED
) {
359 dev_err(&dev
->pdev
->dev
, "host client = %d, is not connected to ME client = %d",
360 cl
->host_client_id
, cl
->me_client_id
);
364 if (cl
== &dev
->iamthif_cl
) {
365 write_cb
= mei_amthif_find_read_list_entry(dev
, file
);
368 timeout
= write_cb
->read_time
+
369 mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER
);
371 if (time_after(jiffies
, timeout
) ||
372 cl
->reading_state
== MEI_READ_COMPLETE
) {
374 list_del(&write_cb
->list
);
375 mei_io_cb_free(write_cb
);
381 /* free entry used in read */
382 if (cl
->reading_state
== MEI_READ_COMPLETE
) {
384 write_cb
= mei_cl_find_read_cb(cl
);
386 list_del(&write_cb
->list
);
387 mei_io_cb_free(write_cb
);
389 cl
->reading_state
= MEI_IDLE
;
392 } else if (cl
->reading_state
== MEI_IDLE
)
396 write_cb
= mei_io_cb_init(cl
, file
);
398 dev_err(&dev
->pdev
->dev
, "write cb allocation failed\n");
402 rets
= mei_io_cb_alloc_req_buf(write_cb
, length
);
406 rets
= copy_from_user(write_cb
->request_buffer
.data
, ubuf
, length
);
410 if (cl
== &dev
->iamthif_cl
) {
411 rets
= mei_amthif_write(dev
, write_cb
);
414 dev_err(&dev
->pdev
->dev
,
415 "amthif write failed with status = %d\n", rets
);
418 mutex_unlock(&dev
->device_lock
);
422 rets
= mei_cl_write(cl
, write_cb
, false);
424 mutex_unlock(&dev
->device_lock
);
426 mei_io_cb_free(write_cb
);
431 * mei_ioctl_connect_client - the connect to fw client IOCTL function
433 * @dev: the device structure
434 * @data: IOCTL connect data, input and output parameters
435 * @file: private data of the file object
437 * Locking: called under "dev->device_lock" lock
439 * returns 0 on success, <0 on failure.
441 static int mei_ioctl_connect_client(struct file
*file
,
442 struct mei_connect_client_data
*data
)
444 struct mei_device
*dev
;
445 struct mei_client
*client
;
450 cl
= file
->private_data
;
451 if (WARN_ON(!cl
|| !cl
->dev
))
456 if (dev
->dev_state
!= MEI_DEV_ENABLED
) {
461 if (cl
->state
!= MEI_FILE_INITIALIZING
&&
462 cl
->state
!= MEI_FILE_DISCONNECTED
) {
467 /* find ME client we're trying to connect to */
468 i
= mei_me_cl_by_uuid(dev
, &data
->in_client_uuid
);
469 if (i
< 0 || dev
->me_clients
[i
].props
.fixed_address
) {
470 dev_dbg(&dev
->pdev
->dev
, "Cannot connect to FW Client UUID = %pUl\n",
471 &data
->in_client_uuid
);
476 cl
->me_client_id
= dev
->me_clients
[i
].client_id
;
477 cl
->state
= MEI_FILE_CONNECTING
;
479 dev_dbg(&dev
->pdev
->dev
, "Connect to FW Client ID = %d\n",
481 dev_dbg(&dev
->pdev
->dev
, "FW Client - Protocol Version = %d\n",
482 dev
->me_clients
[i
].props
.protocol_version
);
483 dev_dbg(&dev
->pdev
->dev
, "FW Client - Max Msg Len = %d\n",
484 dev
->me_clients
[i
].props
.max_msg_length
);
486 /* if we're connecting to amthif client then we will use the
487 * existing connection
489 if (uuid_le_cmp(data
->in_client_uuid
, mei_amthif_guid
) == 0) {
490 dev_dbg(&dev
->pdev
->dev
, "FW Client is amthi\n");
491 if (dev
->iamthif_cl
.state
!= MEI_FILE_CONNECTED
) {
495 clear_bit(cl
->host_client_id
, dev
->host_clients_map
);
500 file
->private_data
= &dev
->iamthif_cl
;
502 client
= &data
->out_client_properties
;
503 client
->max_msg_length
=
504 dev
->me_clients
[i
].props
.max_msg_length
;
505 client
->protocol_version
=
506 dev
->me_clients
[i
].props
.protocol_version
;
507 rets
= dev
->iamthif_cl
.status
;
513 /* prepare the output buffer */
514 client
= &data
->out_client_properties
;
515 client
->max_msg_length
= dev
->me_clients
[i
].props
.max_msg_length
;
516 client
->protocol_version
= dev
->me_clients
[i
].props
.protocol_version
;
517 dev_dbg(&dev
->pdev
->dev
, "Can connect?\n");
520 rets
= mei_cl_connect(cl
, file
);
528 * mei_ioctl - the IOCTL function
530 * @file: pointer to file structure
531 * @cmd: ioctl command
532 * @data: pointer to mei message structure
534 * returns 0 on success , <0 on error
536 static long mei_ioctl(struct file
*file
, unsigned int cmd
, unsigned long data
)
538 struct mei_device
*dev
;
539 struct mei_cl
*cl
= file
->private_data
;
540 struct mei_connect_client_data
*connect_data
= NULL
;
543 if (cmd
!= IOCTL_MEI_CONNECT_CLIENT
)
546 if (WARN_ON(!cl
|| !cl
->dev
))
551 dev_dbg(&dev
->pdev
->dev
, "IOCTL cmd = 0x%x", cmd
);
553 mutex_lock(&dev
->device_lock
);
554 if (dev
->dev_state
!= MEI_DEV_ENABLED
) {
559 dev_dbg(&dev
->pdev
->dev
, ": IOCTL_MEI_CONNECT_CLIENT.\n");
561 connect_data
= kzalloc(sizeof(struct mei_connect_client_data
),
567 dev_dbg(&dev
->pdev
->dev
, "copy connect data from user\n");
568 if (copy_from_user(connect_data
, (char __user
*)data
,
569 sizeof(struct mei_connect_client_data
))) {
570 dev_dbg(&dev
->pdev
->dev
, "failed to copy data from userland\n");
575 rets
= mei_ioctl_connect_client(file
, connect_data
);
577 /* if all is ok, copying the data back to user. */
581 dev_dbg(&dev
->pdev
->dev
, "copy connect data to user\n");
582 if (copy_to_user((char __user
*)data
, connect_data
,
583 sizeof(struct mei_connect_client_data
))) {
584 dev_dbg(&dev
->pdev
->dev
, "failed to copy data to userland\n");
591 mutex_unlock(&dev
->device_lock
);
596 * mei_compat_ioctl - the compat IOCTL function
598 * @file: pointer to file structure
599 * @cmd: ioctl command
600 * @data: pointer to mei message structure
602 * returns 0 on success , <0 on error
605 static long mei_compat_ioctl(struct file
*file
,
606 unsigned int cmd
, unsigned long data
)
608 return mei_ioctl(file
, cmd
, (unsigned long)compat_ptr(data
));
614 * mei_poll - the poll function
616 * @file: pointer to file structure
617 * @wait: pointer to poll_table structure
621 static unsigned int mei_poll(struct file
*file
, poll_table
*wait
)
623 struct mei_cl
*cl
= file
->private_data
;
624 struct mei_device
*dev
;
625 unsigned int mask
= 0;
627 if (WARN_ON(!cl
|| !cl
->dev
))
632 mutex_lock(&dev
->device_lock
);
634 if (!mei_cl_is_connected(cl
)) {
639 mutex_unlock(&dev
->device_lock
);
642 if (cl
== &dev
->iamthif_cl
)
643 return mei_amthif_poll(dev
, file
, wait
);
645 poll_wait(file
, &cl
->tx_wait
, wait
);
647 mutex_lock(&dev
->device_lock
);
649 if (!mei_cl_is_connected(cl
)) {
654 if (MEI_WRITE_COMPLETE
== cl
->writing_state
)
655 mask
|= (POLLIN
| POLLRDNORM
);
658 mutex_unlock(&dev
->device_lock
);
663 * file operations structure will be used for mei char device.
665 static const struct file_operations mei_fops
= {
666 .owner
= THIS_MODULE
,
668 .unlocked_ioctl
= mei_ioctl
,
670 .compat_ioctl
= mei_compat_ioctl
,
673 .release
= mei_release
,
682 static struct miscdevice mei_misc_device
= {
685 .minor
= MISC_DYNAMIC_MINOR
,
689 int mei_register(struct mei_device
*dev
)
692 mei_misc_device
.parent
= &dev
->pdev
->dev
;
693 ret
= misc_register(&mei_misc_device
);
697 if (mei_dbgfs_register(dev
, mei_misc_device
.name
))
698 dev_err(&dev
->pdev
->dev
, "cannot register debugfs\n");
702 EXPORT_SYMBOL_GPL(mei_register
);
704 void mei_deregister(struct mei_device
*dev
)
706 mei_dbgfs_deregister(dev
);
707 misc_deregister(&mei_misc_device
);
708 mei_misc_device
.parent
= NULL
;
710 EXPORT_SYMBOL_GPL(mei_deregister
);
712 static int __init
mei_init(void)
714 return mei_cl_bus_init();
717 static void __exit
mei_exit(void)
722 module_init(mei_init
);
723 module_exit(mei_exit
);
725 MODULE_AUTHOR("Intel Corporation");
726 MODULE_DESCRIPTION("Intel(R) Management Engine Interface");
727 MODULE_LICENSE("GPL v2");