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1/*
2 *
3 * Intel Management Engine Interface (Intel MEI) Linux driver
4 * Copyright (c) 2003-2012, Intel Corporation.
5 *
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.
9 *
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
13 * more details.
14 *
15 */
16#include <linux/module.h>
17#include <linux/moduleparam.h>
18#include <linux/kernel.h>
19#include <linux/device.h>
20#include <linux/slab.h>
21#include <linux/fs.h>
22#include <linux/errno.h>
23#include <linux/types.h>
24#include <linux/fcntl.h>
25#include <linux/poll.h>
26#include <linux/init.h>
27#include <linux/ioctl.h>
28#include <linux/cdev.h>
29#include <linux/sched/signal.h>
30#include <linux/uuid.h>
31#include <linux/compat.h>
32#include <linux/jiffies.h>
33#include <linux/interrupt.h>
34
35#include <linux/mei.h>
36
37#include "mei_dev.h"
38#include "client.h"
39
40/**
41 * mei_open - the open function
42 *
43 * @inode: pointer to inode structure
44 * @file: pointer to file structure
45 *
46 * Return: 0 on success, <0 on error
47 */
48static int mei_open(struct inode *inode, struct file *file)
49{
50 struct mei_device *dev;
51 struct mei_cl *cl;
52
53 int err;
54
55 dev = container_of(inode->i_cdev, struct mei_device, cdev);
56 if (!dev)
57 return -ENODEV;
58
59 mutex_lock(&dev->device_lock);
60
61 if (dev->dev_state != MEI_DEV_ENABLED) {
62 dev_dbg(dev->dev, "dev_state != MEI_ENABLED dev_state = %s\n",
63 mei_dev_state_str(dev->dev_state));
64 err = -ENODEV;
65 goto err_unlock;
66 }
67
68 cl = mei_cl_alloc_linked(dev);
69 if (IS_ERR(cl)) {
70 err = PTR_ERR(cl);
71 goto err_unlock;
72 }
73
74 cl->fp = file;
75 file->private_data = cl;
76
77 mutex_unlock(&dev->device_lock);
78
79 return nonseekable_open(inode, file);
80
81err_unlock:
82 mutex_unlock(&dev->device_lock);
83 return err;
84}
85
86/**
87 * mei_release - the release function
88 *
89 * @inode: pointer to inode structure
90 * @file: pointer to file structure
91 *
92 * Return: 0 on success, <0 on error
93 */
94static int mei_release(struct inode *inode, struct file *file)
95{
96 struct mei_cl *cl = file->private_data;
97 struct mei_device *dev;
98 int rets;
99
100 if (WARN_ON(!cl || !cl->dev))
101 return -ENODEV;
102
103 dev = cl->dev;
104
105 mutex_lock(&dev->device_lock);
106
107 rets = mei_cl_disconnect(cl);
108
109 mei_cl_flush_queues(cl, file);
110 cl_dbg(dev, cl, "removing\n");
111
112 mei_cl_unlink(cl);
113
114 file->private_data = NULL;
115
116 kfree(cl);
117
118 mutex_unlock(&dev->device_lock);
119 return rets;
120}
121
122
123/**
124 * mei_read - the read function.
125 *
126 * @file: pointer to file structure
127 * @ubuf: pointer to user buffer
128 * @length: buffer length
129 * @offset: data offset in buffer
130 *
131 * Return: >=0 data length on success , <0 on error
132 */
133static ssize_t mei_read(struct file *file, char __user *ubuf,
134 size_t length, loff_t *offset)
135{
136 struct mei_cl *cl = file->private_data;
137 struct mei_device *dev;
138 struct mei_cl_cb *cb = NULL;
139 bool nonblock = !!(file->f_flags & O_NONBLOCK);
140 int rets;
141
142 if (WARN_ON(!cl || !cl->dev))
143 return -ENODEV;
144
145 dev = cl->dev;
146
147
148 mutex_lock(&dev->device_lock);
149 if (dev->dev_state != MEI_DEV_ENABLED) {
150 rets = -ENODEV;
151 goto out;
152 }
153
154 if (length == 0) {
155 rets = 0;
156 goto out;
157 }
158
159 if (ubuf == NULL) {
160 rets = -EMSGSIZE;
161 goto out;
162 }
163
164 cb = mei_cl_read_cb(cl, file);
165 if (cb)
166 goto copy_buffer;
167
168 if (*offset > 0)
169 *offset = 0;
170
171 rets = mei_cl_read_start(cl, length, file);
172 if (rets && rets != -EBUSY) {
173 cl_dbg(dev, cl, "mei start read failure status = %d\n", rets);
174 goto out;
175 }
176
177 if (nonblock) {
178 rets = -EAGAIN;
179 goto out;
180 }
181
182 mutex_unlock(&dev->device_lock);
183 if (wait_event_interruptible(cl->rx_wait,
184 !list_empty(&cl->rd_completed) ||
185 !mei_cl_is_connected(cl))) {
186 if (signal_pending(current))
187 return -EINTR;
188 return -ERESTARTSYS;
189 }
190 mutex_lock(&dev->device_lock);
191
192 if (!mei_cl_is_connected(cl)) {
193 rets = -ENODEV;
194 goto out;
195 }
196
197 cb = mei_cl_read_cb(cl, file);
198 if (!cb) {
199 rets = 0;
200 goto out;
201 }
202
203copy_buffer:
204 /* now copy the data to user space */
205 if (cb->status) {
206 rets = cb->status;
207 cl_dbg(dev, cl, "read operation failed %d\n", rets);
208 goto free;
209 }
210
211 cl_dbg(dev, cl, "buf.size = %zu buf.idx = %zu offset = %lld\n",
212 cb->buf.size, cb->buf_idx, *offset);
213 if (*offset >= cb->buf_idx) {
214 rets = 0;
215 goto free;
216 }
217
218 /* length is being truncated to PAGE_SIZE,
219 * however buf_idx may point beyond that */
220 length = min_t(size_t, length, cb->buf_idx - *offset);
221
222 if (copy_to_user(ubuf, cb->buf.data + *offset, length)) {
223 dev_dbg(dev->dev, "failed to copy data to userland\n");
224 rets = -EFAULT;
225 goto free;
226 }
227
228 rets = length;
229 *offset += length;
230 /* not all data was read, keep the cb */
231 if (*offset < cb->buf_idx)
232 goto out;
233
234free:
235 mei_io_cb_free(cb);
236 *offset = 0;
237
238out:
239 cl_dbg(dev, cl, "end mei read rets = %d\n", rets);
240 mutex_unlock(&dev->device_lock);
241 return rets;
242}
243/**
244 * mei_write - the write function.
245 *
246 * @file: pointer to file structure
247 * @ubuf: pointer to user buffer
248 * @length: buffer length
249 * @offset: data offset in buffer
250 *
251 * Return: >=0 data length on success , <0 on error
252 */
253static ssize_t mei_write(struct file *file, const char __user *ubuf,
254 size_t length, loff_t *offset)
255{
256 struct mei_cl *cl = file->private_data;
257 struct mei_cl_cb *cb;
258 struct mei_device *dev;
259 int rets;
260
261 if (WARN_ON(!cl || !cl->dev))
262 return -ENODEV;
263
264 dev = cl->dev;
265
266 mutex_lock(&dev->device_lock);
267
268 if (dev->dev_state != MEI_DEV_ENABLED) {
269 rets = -ENODEV;
270 goto out;
271 }
272
273 if (!mei_cl_is_connected(cl)) {
274 cl_err(dev, cl, "is not connected");
275 rets = -ENODEV;
276 goto out;
277 }
278
279 if (!mei_me_cl_is_active(cl->me_cl)) {
280 rets = -ENOTTY;
281 goto out;
282 }
283
284 if (length > mei_cl_mtu(cl)) {
285 rets = -EFBIG;
286 goto out;
287 }
288
289 if (length == 0) {
290 rets = 0;
291 goto out;
292 }
293
294 while (cl->tx_cb_queued >= dev->tx_queue_limit) {
295 if (file->f_flags & O_NONBLOCK) {
296 rets = -EAGAIN;
297 goto out;
298 }
299 mutex_unlock(&dev->device_lock);
300 rets = wait_event_interruptible(cl->tx_wait,
301 cl->writing_state == MEI_WRITE_COMPLETE ||
302 (!mei_cl_is_connected(cl)));
303 mutex_lock(&dev->device_lock);
304 if (rets) {
305 if (signal_pending(current))
306 rets = -EINTR;
307 goto out;
308 }
309 if (!mei_cl_is_connected(cl)) {
310 rets = -ENODEV;
311 goto out;
312 }
313 }
314
315 *offset = 0;
316 cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, file);
317 if (!cb) {
318 rets = -ENOMEM;
319 goto out;
320 }
321
322 rets = copy_from_user(cb->buf.data, ubuf, length);
323 if (rets) {
324 dev_dbg(dev->dev, "failed to copy data from userland\n");
325 rets = -EFAULT;
326 mei_io_cb_free(cb);
327 goto out;
328 }
329
330 rets = mei_cl_write(cl, cb);
331out:
332 mutex_unlock(&dev->device_lock);
333 return rets;
334}
335
336/**
337 * mei_ioctl_connect_client - the connect to fw client IOCTL function
338 *
339 * @file: private data of the file object
340 * @data: IOCTL connect data, input and output parameters
341 *
342 * Locking: called under "dev->device_lock" lock
343 *
344 * Return: 0 on success, <0 on failure.
345 */
346static int mei_ioctl_connect_client(struct file *file,
347 struct mei_connect_client_data *data)
348{
349 struct mei_device *dev;
350 struct mei_client *client;
351 struct mei_me_client *me_cl;
352 struct mei_cl *cl;
353 int rets;
354
355 cl = file->private_data;
356 dev = cl->dev;
357
358 if (dev->dev_state != MEI_DEV_ENABLED)
359 return -ENODEV;
360
361 if (cl->state != MEI_FILE_INITIALIZING &&
362 cl->state != MEI_FILE_DISCONNECTED)
363 return -EBUSY;
364
365 /* find ME client we're trying to connect to */
366 me_cl = mei_me_cl_by_uuid(dev, &data->in_client_uuid);
367 if (!me_cl) {
368 dev_dbg(dev->dev, "Cannot connect to FW Client UUID = %pUl\n",
369 &data->in_client_uuid);
370 rets = -ENOTTY;
371 goto end;
372 }
373
374 if (me_cl->props.fixed_address) {
375 bool forbidden = dev->override_fixed_address ?
376 !dev->allow_fixed_address : !dev->hbm_f_fa_supported;
377 if (forbidden) {
378 dev_dbg(dev->dev, "Connection forbidden to FW Client UUID = %pUl\n",
379 &data->in_client_uuid);
380 rets = -ENOTTY;
381 goto end;
382 }
383 }
384
385 dev_dbg(dev->dev, "Connect to FW Client ID = %d\n",
386 me_cl->client_id);
387 dev_dbg(dev->dev, "FW Client - Protocol Version = %d\n",
388 me_cl->props.protocol_version);
389 dev_dbg(dev->dev, "FW Client - Max Msg Len = %d\n",
390 me_cl->props.max_msg_length);
391
392 /* prepare the output buffer */
393 client = &data->out_client_properties;
394 client->max_msg_length = me_cl->props.max_msg_length;
395 client->protocol_version = me_cl->props.protocol_version;
396 dev_dbg(dev->dev, "Can connect?\n");
397
398 rets = mei_cl_connect(cl, me_cl, file);
399
400end:
401 mei_me_cl_put(me_cl);
402 return rets;
403}
404
405/**
406 * mei_ioctl_client_notify_request -
407 * propagate event notification request to client
408 *
409 * @file: pointer to file structure
410 * @request: 0 - disable, 1 - enable
411 *
412 * Return: 0 on success , <0 on error
413 */
414static int mei_ioctl_client_notify_request(const struct file *file, u32 request)
415{
416 struct mei_cl *cl = file->private_data;
417
418 if (request != MEI_HBM_NOTIFICATION_START &&
419 request != MEI_HBM_NOTIFICATION_STOP)
420 return -EINVAL;
421
422 return mei_cl_notify_request(cl, file, (u8)request);
423}
424
425/**
426 * mei_ioctl_client_notify_get - wait for notification request
427 *
428 * @file: pointer to file structure
429 * @notify_get: 0 - disable, 1 - enable
430 *
431 * Return: 0 on success , <0 on error
432 */
433static int mei_ioctl_client_notify_get(const struct file *file, u32 *notify_get)
434{
435 struct mei_cl *cl = file->private_data;
436 bool notify_ev;
437 bool block = (file->f_flags & O_NONBLOCK) == 0;
438 int rets;
439
440 rets = mei_cl_notify_get(cl, block, ¬ify_ev);
441 if (rets)
442 return rets;
443
444 *notify_get = notify_ev ? 1 : 0;
445 return 0;
446}
447
448/**
449 * mei_ioctl - the IOCTL function
450 *
451 * @file: pointer to file structure
452 * @cmd: ioctl command
453 * @data: pointer to mei message structure
454 *
455 * Return: 0 on success , <0 on error
456 */
457static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data)
458{
459 struct mei_device *dev;
460 struct mei_cl *cl = file->private_data;
461 struct mei_connect_client_data connect_data;
462 u32 notify_get, notify_req;
463 int rets;
464
465
466 if (WARN_ON(!cl || !cl->dev))
467 return -ENODEV;
468
469 dev = cl->dev;
470
471 dev_dbg(dev->dev, "IOCTL cmd = 0x%x", cmd);
472
473 mutex_lock(&dev->device_lock);
474 if (dev->dev_state != MEI_DEV_ENABLED) {
475 rets = -ENODEV;
476 goto out;
477 }
478
479 switch (cmd) {
480 case IOCTL_MEI_CONNECT_CLIENT:
481 dev_dbg(dev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n");
482 if (copy_from_user(&connect_data, (char __user *)data,
483 sizeof(struct mei_connect_client_data))) {
484 dev_dbg(dev->dev, "failed to copy data from userland\n");
485 rets = -EFAULT;
486 goto out;
487 }
488
489 rets = mei_ioctl_connect_client(file, &connect_data);
490 if (rets)
491 goto out;
492
493 /* if all is ok, copying the data back to user. */
494 if (copy_to_user((char __user *)data, &connect_data,
495 sizeof(struct mei_connect_client_data))) {
496 dev_dbg(dev->dev, "failed to copy data to userland\n");
497 rets = -EFAULT;
498 goto out;
499 }
500
501 break;
502
503 case IOCTL_MEI_NOTIFY_SET:
504 dev_dbg(dev->dev, ": IOCTL_MEI_NOTIFY_SET.\n");
505 if (copy_from_user(¬ify_req,
506 (char __user *)data, sizeof(notify_req))) {
507 dev_dbg(dev->dev, "failed to copy data from userland\n");
508 rets = -EFAULT;
509 goto out;
510 }
511 rets = mei_ioctl_client_notify_request(file, notify_req);
512 break;
513
514 case IOCTL_MEI_NOTIFY_GET:
515 dev_dbg(dev->dev, ": IOCTL_MEI_NOTIFY_GET.\n");
516 rets = mei_ioctl_client_notify_get(file, ¬ify_get);
517 if (rets)
518 goto out;
519
520 dev_dbg(dev->dev, "copy connect data to user\n");
521 if (copy_to_user((char __user *)data,
522 ¬ify_get, sizeof(notify_get))) {
523 dev_dbg(dev->dev, "failed to copy data to userland\n");
524 rets = -EFAULT;
525 goto out;
526
527 }
528 break;
529
530 default:
531 rets = -ENOIOCTLCMD;
532 }
533
534out:
535 mutex_unlock(&dev->device_lock);
536 return rets;
537}
538
539/**
540 * mei_compat_ioctl - the compat IOCTL function
541 *
542 * @file: pointer to file structure
543 * @cmd: ioctl command
544 * @data: pointer to mei message structure
545 *
546 * Return: 0 on success , <0 on error
547 */
548#ifdef CONFIG_COMPAT
549static long mei_compat_ioctl(struct file *file,
550 unsigned int cmd, unsigned long data)
551{
552 return mei_ioctl(file, cmd, (unsigned long)compat_ptr(data));
553}
554#endif
555
556
557/**
558 * mei_poll - the poll function
559 *
560 * @file: pointer to file structure
561 * @wait: pointer to poll_table structure
562 *
563 * Return: poll mask
564 */
565static __poll_t mei_poll(struct file *file, poll_table *wait)
566{
567 __poll_t req_events = poll_requested_events(wait);
568 struct mei_cl *cl = file->private_data;
569 struct mei_device *dev;
570 __poll_t mask = 0;
571 bool notify_en;
572
573 if (WARN_ON(!cl || !cl->dev))
574 return EPOLLERR;
575
576 dev = cl->dev;
577
578 mutex_lock(&dev->device_lock);
579
580 notify_en = cl->notify_en && (req_events & EPOLLPRI);
581
582 if (dev->dev_state != MEI_DEV_ENABLED ||
583 !mei_cl_is_connected(cl)) {
584 mask = EPOLLERR;
585 goto out;
586 }
587
588 if (notify_en) {
589 poll_wait(file, &cl->ev_wait, wait);
590 if (cl->notify_ev)
591 mask |= EPOLLPRI;
592 }
593
594 if (req_events & (EPOLLIN | EPOLLRDNORM)) {
595 poll_wait(file, &cl->rx_wait, wait);
596
597 if (!list_empty(&cl->rd_completed))
598 mask |= EPOLLIN | EPOLLRDNORM;
599 else
600 mei_cl_read_start(cl, mei_cl_mtu(cl), file);
601 }
602
603 if (req_events & (POLLOUT | POLLWRNORM)) {
604 poll_wait(file, &cl->tx_wait, wait);
605 if (cl->tx_cb_queued < dev->tx_queue_limit)
606 mask |= POLLOUT | POLLWRNORM;
607 }
608
609out:
610 mutex_unlock(&dev->device_lock);
611 return mask;
612}
613
614/**
615 * mei_cl_is_write_queued - check if the client has pending writes.
616 *
617 * @cl: writing host client
618 *
619 * Return: true if client is writing, false otherwise.
620 */
621static bool mei_cl_is_write_queued(struct mei_cl *cl)
622{
623 struct mei_device *dev = cl->dev;
624 struct mei_cl_cb *cb;
625
626 list_for_each_entry(cb, &dev->write_list, list)
627 if (cb->cl == cl)
628 return true;
629 list_for_each_entry(cb, &dev->write_waiting_list, list)
630 if (cb->cl == cl)
631 return true;
632 return false;
633}
634
635/**
636 * mei_fsync - the fsync handler
637 *
638 * @fp: pointer to file structure
639 * @start: unused
640 * @end: unused
641 * @datasync: unused
642 *
643 * Return: 0 on success, -ENODEV if client is not connected
644 */
645static int mei_fsync(struct file *fp, loff_t start, loff_t end, int datasync)
646{
647 struct mei_cl *cl = fp->private_data;
648 struct mei_device *dev;
649 int rets;
650
651 if (WARN_ON(!cl || !cl->dev))
652 return -ENODEV;
653
654 dev = cl->dev;
655
656 mutex_lock(&dev->device_lock);
657
658 if (dev->dev_state != MEI_DEV_ENABLED || !mei_cl_is_connected(cl)) {
659 rets = -ENODEV;
660 goto out;
661 }
662
663 while (mei_cl_is_write_queued(cl)) {
664 mutex_unlock(&dev->device_lock);
665 rets = wait_event_interruptible(cl->tx_wait,
666 cl->writing_state == MEI_WRITE_COMPLETE ||
667 !mei_cl_is_connected(cl));
668 mutex_lock(&dev->device_lock);
669 if (rets) {
670 if (signal_pending(current))
671 rets = -EINTR;
672 goto out;
673 }
674 if (!mei_cl_is_connected(cl)) {
675 rets = -ENODEV;
676 goto out;
677 }
678 }
679 rets = 0;
680out:
681 mutex_unlock(&dev->device_lock);
682 return rets;
683}
684
685/**
686 * mei_fasync - asynchronous io support
687 *
688 * @fd: file descriptor
689 * @file: pointer to file structure
690 * @band: band bitmap
691 *
692 * Return: negative on error,
693 * 0 if it did no changes,
694 * and positive a process was added or deleted
695 */
696static int mei_fasync(int fd, struct file *file, int band)
697{
698
699 struct mei_cl *cl = file->private_data;
700
701 if (!mei_cl_is_connected(cl))
702 return -ENODEV;
703
704 return fasync_helper(fd, file, band, &cl->ev_async);
705}
706
707/**
708 * fw_status_show - mei device fw_status attribute show method
709 *
710 * @device: device pointer
711 * @attr: attribute pointer
712 * @buf: char out buffer
713 *
714 * Return: number of the bytes printed into buf or error
715 */
716static ssize_t fw_status_show(struct device *device,
717 struct device_attribute *attr, char *buf)
718{
719 struct mei_device *dev = dev_get_drvdata(device);
720 struct mei_fw_status fw_status;
721 int err, i;
722 ssize_t cnt = 0;
723
724 mutex_lock(&dev->device_lock);
725 err = mei_fw_status(dev, &fw_status);
726 mutex_unlock(&dev->device_lock);
727 if (err) {
728 dev_err(device, "read fw_status error = %d\n", err);
729 return err;
730 }
731
732 for (i = 0; i < fw_status.count; i++)
733 cnt += scnprintf(buf + cnt, PAGE_SIZE - cnt, "%08X\n",
734 fw_status.status[i]);
735 return cnt;
736}
737static DEVICE_ATTR_RO(fw_status);
738
739/**
740 * hbm_ver_show - display HBM protocol version negotiated with FW
741 *
742 * @device: device pointer
743 * @attr: attribute pointer
744 * @buf: char out buffer
745 *
746 * Return: number of the bytes printed into buf or error
747 */
748static ssize_t hbm_ver_show(struct device *device,
749 struct device_attribute *attr, char *buf)
750{
751 struct mei_device *dev = dev_get_drvdata(device);
752 struct hbm_version ver;
753
754 mutex_lock(&dev->device_lock);
755 ver = dev->version;
756 mutex_unlock(&dev->device_lock);
757
758 return sprintf(buf, "%u.%u\n", ver.major_version, ver.minor_version);
759}
760static DEVICE_ATTR_RO(hbm_ver);
761
762/**
763 * hbm_ver_drv_show - display HBM protocol version advertised by driver
764 *
765 * @device: device pointer
766 * @attr: attribute pointer
767 * @buf: char out buffer
768 *
769 * Return: number of the bytes printed into buf or error
770 */
771static ssize_t hbm_ver_drv_show(struct device *device,
772 struct device_attribute *attr, char *buf)
773{
774 return sprintf(buf, "%u.%u\n", HBM_MAJOR_VERSION, HBM_MINOR_VERSION);
775}
776static DEVICE_ATTR_RO(hbm_ver_drv);
777
778static ssize_t tx_queue_limit_show(struct device *device,
779 struct device_attribute *attr, char *buf)
780{
781 struct mei_device *dev = dev_get_drvdata(device);
782 u8 size = 0;
783
784 mutex_lock(&dev->device_lock);
785 size = dev->tx_queue_limit;
786 mutex_unlock(&dev->device_lock);
787
788 return snprintf(buf, PAGE_SIZE, "%u\n", size);
789}
790
791static ssize_t tx_queue_limit_store(struct device *device,
792 struct device_attribute *attr,
793 const char *buf, size_t count)
794{
795 struct mei_device *dev = dev_get_drvdata(device);
796 u8 limit;
797 unsigned int inp;
798 int err;
799
800 err = kstrtouint(buf, 10, &inp);
801 if (err)
802 return err;
803 if (inp > MEI_TX_QUEUE_LIMIT_MAX || inp < MEI_TX_QUEUE_LIMIT_MIN)
804 return -EINVAL;
805 limit = inp;
806
807 mutex_lock(&dev->device_lock);
808 dev->tx_queue_limit = limit;
809 mutex_unlock(&dev->device_lock);
810
811 return count;
812}
813static DEVICE_ATTR_RW(tx_queue_limit);
814
815static struct attribute *mei_attrs[] = {
816 &dev_attr_fw_status.attr,
817 &dev_attr_hbm_ver.attr,
818 &dev_attr_hbm_ver_drv.attr,
819 &dev_attr_tx_queue_limit.attr,
820 NULL
821};
822ATTRIBUTE_GROUPS(mei);
823
824/*
825 * file operations structure will be used for mei char device.
826 */
827static const struct file_operations mei_fops = {
828 .owner = THIS_MODULE,
829 .read = mei_read,
830 .unlocked_ioctl = mei_ioctl,
831#ifdef CONFIG_COMPAT
832 .compat_ioctl = mei_compat_ioctl,
833#endif
834 .open = mei_open,
835 .release = mei_release,
836 .write = mei_write,
837 .poll = mei_poll,
838 .fsync = mei_fsync,
839 .fasync = mei_fasync,
840 .llseek = no_llseek
841};
842
843static struct class *mei_class;
844static dev_t mei_devt;
845#define MEI_MAX_DEVS MINORMASK
846static DEFINE_MUTEX(mei_minor_lock);
847static DEFINE_IDR(mei_idr);
848
849/**
850 * mei_minor_get - obtain next free device minor number
851 *
852 * @dev: device pointer
853 *
854 * Return: allocated minor, or -ENOSPC if no free minor left
855 */
856static int mei_minor_get(struct mei_device *dev)
857{
858 int ret;
859
860 mutex_lock(&mei_minor_lock);
861 ret = idr_alloc(&mei_idr, dev, 0, MEI_MAX_DEVS, GFP_KERNEL);
862 if (ret >= 0)
863 dev->minor = ret;
864 else if (ret == -ENOSPC)
865 dev_err(dev->dev, "too many mei devices\n");
866
867 mutex_unlock(&mei_minor_lock);
868 return ret;
869}
870
871/**
872 * mei_minor_free - mark device minor number as free
873 *
874 * @dev: device pointer
875 */
876static void mei_minor_free(struct mei_device *dev)
877{
878 mutex_lock(&mei_minor_lock);
879 idr_remove(&mei_idr, dev->minor);
880 mutex_unlock(&mei_minor_lock);
881}
882
883int mei_register(struct mei_device *dev, struct device *parent)
884{
885 struct device *clsdev; /* class device */
886 int ret, devno;
887
888 ret = mei_minor_get(dev);
889 if (ret < 0)
890 return ret;
891
892 /* Fill in the data structures */
893 devno = MKDEV(MAJOR(mei_devt), dev->minor);
894 cdev_init(&dev->cdev, &mei_fops);
895 dev->cdev.owner = parent->driver->owner;
896
897 /* Add the device */
898 ret = cdev_add(&dev->cdev, devno, 1);
899 if (ret) {
900 dev_err(parent, "unable to add device %d:%d\n",
901 MAJOR(mei_devt), dev->minor);
902 goto err_dev_add;
903 }
904
905 clsdev = device_create_with_groups(mei_class, parent, devno,
906 dev, mei_groups,
907 "mei%d", dev->minor);
908
909 if (IS_ERR(clsdev)) {
910 dev_err(parent, "unable to create device %d:%d\n",
911 MAJOR(mei_devt), dev->minor);
912 ret = PTR_ERR(clsdev);
913 goto err_dev_create;
914 }
915
916 ret = mei_dbgfs_register(dev, dev_name(clsdev));
917 if (ret) {
918 dev_err(clsdev, "cannot register debugfs ret = %d\n", ret);
919 goto err_dev_dbgfs;
920 }
921
922 return 0;
923
924err_dev_dbgfs:
925 device_destroy(mei_class, devno);
926err_dev_create:
927 cdev_del(&dev->cdev);
928err_dev_add:
929 mei_minor_free(dev);
930 return ret;
931}
932EXPORT_SYMBOL_GPL(mei_register);
933
934void mei_deregister(struct mei_device *dev)
935{
936 int devno;
937
938 devno = dev->cdev.dev;
939 cdev_del(&dev->cdev);
940
941 mei_dbgfs_deregister(dev);
942
943 device_destroy(mei_class, devno);
944
945 mei_minor_free(dev);
946}
947EXPORT_SYMBOL_GPL(mei_deregister);
948
949static int __init mei_init(void)
950{
951 int ret;
952
953 mei_class = class_create(THIS_MODULE, "mei");
954 if (IS_ERR(mei_class)) {
955 pr_err("couldn't create class\n");
956 ret = PTR_ERR(mei_class);
957 goto err;
958 }
959
960 ret = alloc_chrdev_region(&mei_devt, 0, MEI_MAX_DEVS, "mei");
961 if (ret < 0) {
962 pr_err("unable to allocate char dev region\n");
963 goto err_class;
964 }
965
966 ret = mei_cl_bus_init();
967 if (ret < 0) {
968 pr_err("unable to initialize bus\n");
969 goto err_chrdev;
970 }
971
972 return 0;
973
974err_chrdev:
975 unregister_chrdev_region(mei_devt, MEI_MAX_DEVS);
976err_class:
977 class_destroy(mei_class);
978err:
979 return ret;
980}
981
982static void __exit mei_exit(void)
983{
984 unregister_chrdev_region(mei_devt, MEI_MAX_DEVS);
985 class_destroy(mei_class);
986 mei_cl_bus_exit();
987}
988
989module_init(mei_init);
990module_exit(mei_exit);
991
992MODULE_AUTHOR("Intel Corporation");
993MODULE_DESCRIPTION("Intel(R) Management Engine Interface");
994MODULE_LICENSE("GPL v2");
995