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
17#include <linux/pci.h>
18#include <linux/sched.h>
19#include <linux/wait.h>
20#include <linux/delay.h>
21
22#include "mei_dev.h"
23#include "hw.h"
24#include "interface.h"
25#include "mei.h"
26
27const uuid_le mei_amthi_guid  = UUID_LE(0x12f80028, 0xb4b7, 0x4b2d, 0xac,
28						0xa8, 0x46, 0xe0, 0xff, 0x65,
29						0x81, 0x4c);
30
31/**
32 * mei_io_list_init - Sets up a queue list.
33 *
34 * @list: An instance io list structure
35 * @dev: the device structure
36 */
37void mei_io_list_init(struct mei_io_list *list)
38{
39	/* initialize our queue list */
40	INIT_LIST_HEAD(&list->mei_cb.cb_list);
41}
42
43/**
44 * mei_io_list_flush - removes list entry belonging to cl.
45 *
46 * @list:  An instance of our list structure
47 * @cl: private data of the file object
48 */
49void mei_io_list_flush(struct mei_io_list *list, struct mei_cl *cl)
50{
51	struct mei_cl_cb *pos;
52	struct mei_cl_cb *next;
53
54	list_for_each_entry_safe(pos, next, &list->mei_cb.cb_list, cb_list) {
55		if (pos->file_private) {
56			struct mei_cl *cl_tmp;
57			cl_tmp = (struct mei_cl *)pos->file_private;
58			if (mei_cl_cmp_id(cl, cl_tmp))
59				list_del(&pos->cb_list);
60		}
61	}
62}
63/**
64 * mei_cl_flush_queues - flushes queue lists belonging to cl.
65 *
66 * @dev: the device structure
67 * @cl: private data of the file object
68 */
69int mei_cl_flush_queues(struct mei_cl *cl)
70{
71	if (!cl || !cl->dev)
72		return -EINVAL;
73
74	dev_dbg(&cl->dev->pdev->dev, "remove list entry belonging to cl\n");
75	mei_io_list_flush(&cl->dev->read_list, cl);
76	mei_io_list_flush(&cl->dev->write_list, cl);
77	mei_io_list_flush(&cl->dev->write_waiting_list, cl);
78	mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
79	mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
80	mei_io_list_flush(&cl->dev->amthi_cmd_list, cl);
81	mei_io_list_flush(&cl->dev->amthi_read_complete_list, cl);
82	return 0;
83}
84
85
86
87/**
88 * mei_reset_iamthif_params - initializes mei device iamthif
89 *
90 * @dev: the device structure
91 */
92static void mei_reset_iamthif_params(struct mei_device *dev)
93{
94	/* reset iamthif parameters. */
95	dev->iamthif_current_cb = NULL;
96	dev->iamthif_msg_buf_size = 0;
97	dev->iamthif_msg_buf_index = 0;
98	dev->iamthif_canceled = false;
99	dev->iamthif_ioctl = false;
100	dev->iamthif_state = MEI_IAMTHIF_IDLE;
101	dev->iamthif_timer = 0;
102}
103
104/**
105 * init_mei_device - allocates and initializes the mei device structure
106 *
107 * @pdev: The pci device structure
108 *
109 * returns The mei_device_device pointer on success, NULL on failure.
110 */
111struct mei_device *mei_device_init(struct pci_dev *pdev)
112{
113	struct mei_device *dev;
114
115	dev = kzalloc(sizeof(struct mei_device), GFP_KERNEL);
116	if (!dev)
117		return NULL;
118
119	/* setup our list array */
120	INIT_LIST_HEAD(&dev->file_list);
121	INIT_LIST_HEAD(&dev->wd_cl.link);
122	INIT_LIST_HEAD(&dev->iamthif_cl.link);
123	mutex_init(&dev->device_lock);
124	init_waitqueue_head(&dev->wait_recvd_msg);
125	init_waitqueue_head(&dev->wait_stop_wd);
126	dev->mei_state = MEI_INITIALIZING;
127	dev->iamthif_state = MEI_IAMTHIF_IDLE;
128	dev->wd_interface_reg = false;
129
130
131	mei_io_list_init(&dev->read_list);
132	mei_io_list_init(&dev->write_list);
133	mei_io_list_init(&dev->write_waiting_list);
134	mei_io_list_init(&dev->ctrl_wr_list);
135	mei_io_list_init(&dev->ctrl_rd_list);
136	mei_io_list_init(&dev->amthi_cmd_list);
137	mei_io_list_init(&dev->amthi_read_complete_list);
138	dev->pdev = pdev;
139	return dev;
140}
141
142/**
143 * mei_hw_init - initializes host and fw to start work.
144 *
145 * @dev: the device structure
146 *
147 * returns 0 on success, <0 on failure.
148 */
149int mei_hw_init(struct mei_device *dev)
150{
151	int err = 0;
152	int ret;
153
154	mutex_lock(&dev->device_lock);
155
156	dev->host_hw_state = mei_hcsr_read(dev);
157	dev->me_hw_state = mei_mecsr_read(dev);
158	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, mestate = 0x%08x.\n",
159	    dev->host_hw_state, dev->me_hw_state);
160
161	/* acknowledge interrupt and stop interupts */
162	if ((dev->host_hw_state & H_IS) == H_IS)
163		mei_reg_write(dev, H_CSR, dev->host_hw_state);
164
165	dev->recvd_msg = false;
166	dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
167
168	mei_reset(dev, 1);
169
170	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
171	    dev->host_hw_state, dev->me_hw_state);
172
173	/* wait for ME to turn on ME_RDY */
174	if (!dev->recvd_msg) {
175		mutex_unlock(&dev->device_lock);
176		err = wait_event_interruptible_timeout(dev->wait_recvd_msg,
177			dev->recvd_msg, MEI_INTEROP_TIMEOUT);
178		mutex_lock(&dev->device_lock);
179	}
180
181	if (err <= 0 && !dev->recvd_msg) {
182		dev->mei_state = MEI_DISABLED;
183		dev_dbg(&dev->pdev->dev,
184			"wait_event_interruptible_timeout failed"
185			"on wait for ME to turn on ME_RDY.\n");
186		ret = -ENODEV;
187		goto out;
188	}
189
190	if (!(((dev->host_hw_state & H_RDY) == H_RDY) &&
191	      ((dev->me_hw_state & ME_RDY_HRA) == ME_RDY_HRA))) {
192		dev->mei_state = MEI_DISABLED;
193		dev_dbg(&dev->pdev->dev,
194			"host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
195			dev->host_hw_state, dev->me_hw_state);
196
197		if (!(dev->host_hw_state & H_RDY))
198			dev_dbg(&dev->pdev->dev, "host turn off H_RDY.\n");
199
200		if (!(dev->me_hw_state & ME_RDY_HRA))
201			dev_dbg(&dev->pdev->dev, "ME turn off ME_RDY.\n");
202
203		printk(KERN_ERR "mei: link layer initialization failed.\n");
204		ret = -ENODEV;
205		goto out;
206	}
207
208	if (dev->version.major_version != HBM_MAJOR_VERSION ||
209	    dev->version.minor_version != HBM_MINOR_VERSION) {
210		dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
211		ret = -ENODEV;
212		goto out;
213	}
214
215	dev->recvd_msg = false;
216	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
217	    dev->host_hw_state, dev->me_hw_state);
218	dev_dbg(&dev->pdev->dev, "ME turn on ME_RDY and host turn on H_RDY.\n");
219	dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
220	dev_dbg(&dev->pdev->dev, "MEI  start success.\n");
221	ret = 0;
222
223out:
224	mutex_unlock(&dev->device_lock);
225	return ret;
226}
227
228/**
229 * mei_hw_reset - resets fw via mei csr register.
230 *
231 * @dev: the device structure
232 * @interrupts_enabled: if interrupt should be enabled after reset.
233 */
234static void mei_hw_reset(struct mei_device *dev, int interrupts_enabled)
235{
236	dev->host_hw_state |= (H_RST | H_IG);
237
238	if (interrupts_enabled)
239		mei_enable_interrupts(dev);
240	else
241		mei_disable_interrupts(dev);
242}
243
244/**
245 * mei_reset - resets host and fw.
246 *
247 * @dev: the device structure
248 * @interrupts_enabled: if interrupt should be enabled after reset.
249 */
250void mei_reset(struct mei_device *dev, int interrupts_enabled)
251{
252	struct mei_cl *cl_pos = NULL;
253	struct mei_cl *cl_next = NULL;
254	struct mei_cl_cb *cb_pos = NULL;
255	struct mei_cl_cb *cb_next = NULL;
256	bool unexpected;
257
258	if (dev->mei_state == MEI_RECOVERING_FROM_RESET) {
259		dev->need_reset = true;
260		return;
261	}
262
263	unexpected = (dev->mei_state != MEI_INITIALIZING &&
264			dev->mei_state != MEI_DISABLED &&
265			dev->mei_state != MEI_POWER_DOWN &&
266			dev->mei_state != MEI_POWER_UP);
267
268	dev->host_hw_state = mei_hcsr_read(dev);
269
270	dev_dbg(&dev->pdev->dev, "before reset host_hw_state = 0x%08x.\n",
271	    dev->host_hw_state);
272
273	mei_hw_reset(dev, interrupts_enabled);
274
275	dev->host_hw_state &= ~H_RST;
276	dev->host_hw_state |= H_IG;
277
278	mei_hcsr_set(dev);
279
280	dev_dbg(&dev->pdev->dev, "currently saved host_hw_state = 0x%08x.\n",
281	    dev->host_hw_state);
282
283	dev->need_reset = false;
284
285	if (dev->mei_state != MEI_INITIALIZING) {
286		if (dev->mei_state != MEI_DISABLED &&
287		    dev->mei_state != MEI_POWER_DOWN)
288			dev->mei_state = MEI_RESETING;
289
290		list_for_each_entry_safe(cl_pos,
291				cl_next, &dev->file_list, link) {
292			cl_pos->state = MEI_FILE_DISCONNECTED;
293			cl_pos->mei_flow_ctrl_creds = 0;
294			cl_pos->read_cb = NULL;
295			cl_pos->timer_count = 0;
296		}
297		/* remove entry if already in list */
298		dev_dbg(&dev->pdev->dev, "list del iamthif and wd file list.\n");
299		mei_remove_client_from_file_list(dev,
300				dev->wd_cl.host_client_id);
301
302		mei_remove_client_from_file_list(dev,
303				dev->iamthif_cl.host_client_id);
304
305		mei_reset_iamthif_params(dev);
306		dev->wd_due_counter = 0;
307		dev->extra_write_index = 0;
308	}
309
310	dev->me_clients_num = 0;
311	dev->rd_msg_hdr = 0;
312	dev->stop = false;
313	dev->wd_pending = false;
314
315	/* update the state of the registers after reset */
316	dev->host_hw_state = mei_hcsr_read(dev);
317	dev->me_hw_state = mei_mecsr_read(dev);
318
319	dev_dbg(&dev->pdev->dev, "after reset host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
320	    dev->host_hw_state, dev->me_hw_state);
321
322	if (unexpected)
323		dev_warn(&dev->pdev->dev, "unexpected reset.\n");
324
325	/* Wake up all readings so they can be interrupted */
326	list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
327		if (waitqueue_active(&cl_pos->rx_wait)) {
328			dev_dbg(&dev->pdev->dev, "Waking up client!\n");
329			wake_up_interruptible(&cl_pos->rx_wait);
330		}
331	}
332	/* remove all waiting requests */
333	list_for_each_entry_safe(cb_pos, cb_next,
334			&dev->write_list.mei_cb.cb_list, cb_list) {
335		list_del(&cb_pos->cb_list);
336		mei_free_cb_private(cb_pos);
337	}
338}
339
340
341
342/**
343 * host_start_message - mei host sends start message.
344 *
345 * @dev: the device structure
346 *
347 * returns none.
348 */
349void mei_host_start_message(struct mei_device *dev)
350{
351	struct mei_msg_hdr *mei_hdr;
352	struct hbm_host_version_request *host_start_req;
353
354	/* host start message */
355	mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
356	mei_hdr->host_addr = 0;
357	mei_hdr->me_addr = 0;
358	mei_hdr->length = sizeof(struct hbm_host_version_request);
359	mei_hdr->msg_complete = 1;
360	mei_hdr->reserved = 0;
361
362	host_start_req =
363	    (struct hbm_host_version_request *) &dev->wr_msg_buf[1];
364	memset(host_start_req, 0, sizeof(struct hbm_host_version_request));
365	host_start_req->hbm_cmd = HOST_START_REQ_CMD;
366	host_start_req->host_version.major_version = HBM_MAJOR_VERSION;
367	host_start_req->host_version.minor_version = HBM_MINOR_VERSION;
368	dev->recvd_msg = false;
369	if (mei_write_message(dev, mei_hdr, (unsigned char *)host_start_req,
370				       mei_hdr->length)) {
371		dev_dbg(&dev->pdev->dev, "write send version message to FW fail.\n");
372		dev->mei_state = MEI_RESETING;
373		mei_reset(dev, 1);
374	}
375	dev->init_clients_state = MEI_START_MESSAGE;
376	dev->init_clients_timer = INIT_CLIENTS_TIMEOUT;
377	return ;
378}
379
380/**
381 * host_enum_clients_message - host sends enumeration client request message.
382 *
383 * @dev: the device structure
384 *
385 * returns none.
386 */
387void mei_host_enum_clients_message(struct mei_device *dev)
388{
389	struct mei_msg_hdr *mei_hdr;
390	struct hbm_host_enum_request *host_enum_req;
391	mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
392	/* enumerate clients */
393	mei_hdr->host_addr = 0;
394	mei_hdr->me_addr = 0;
395	mei_hdr->length = sizeof(struct hbm_host_enum_request);
396	mei_hdr->msg_complete = 1;
397	mei_hdr->reserved = 0;
398
399	host_enum_req = (struct hbm_host_enum_request *) &dev->wr_msg_buf[1];
400	memset(host_enum_req, 0, sizeof(struct hbm_host_enum_request));
401	host_enum_req->hbm_cmd = HOST_ENUM_REQ_CMD;
402	if (mei_write_message(dev, mei_hdr, (unsigned char *)host_enum_req,
403				mei_hdr->length)) {
404		dev->mei_state = MEI_RESETING;
405		dev_dbg(&dev->pdev->dev, "write send enumeration request message to FW fail.\n");
406		mei_reset(dev, 1);
407	}
408	dev->init_clients_state = MEI_ENUM_CLIENTS_MESSAGE;
409	dev->init_clients_timer = INIT_CLIENTS_TIMEOUT;
410	return;
411}
412
413
414/**
415 * allocate_me_clients_storage - allocates storage for me clients
416 *
417 * @dev: the device structure
418 *
419 * returns none.
420 */
421void mei_allocate_me_clients_storage(struct mei_device *dev)
422{
423	struct mei_me_client *clients;
424	int b;
425
426	/* count how many ME clients we have */
427	for_each_set_bit(b, dev->me_clients_map, MEI_CLIENTS_MAX)
428		dev->me_clients_num++;
429
430	if (dev->me_clients_num <= 0)
431		return ;
432
433
434	if (dev->me_clients != NULL) {
435		kfree(dev->me_clients);
436		dev->me_clients = NULL;
437	}
438	dev_dbg(&dev->pdev->dev, "memory allocation for ME clients size=%zd.\n",
439		dev->me_clients_num * sizeof(struct mei_me_client));
440	/* allocate storage for ME clients representation */
441	clients = kcalloc(dev->me_clients_num,
442			sizeof(struct mei_me_client), GFP_KERNEL);
443	if (!clients) {
444		dev_dbg(&dev->pdev->dev, "memory allocation for ME clients failed.\n");
445		dev->mei_state = MEI_RESETING;
446		mei_reset(dev, 1);
447		return ;
448	}
449	dev->me_clients = clients;
450	return ;
451}
452/**
453 * host_client_properties - reads properties for client
454 *
455 * @dev: the device structure
456 *
457 * returns:
458 * 	< 0 - Error.
459 *  = 0 - no more clients.
460 *  = 1 - still have clients to send properties request.
461 */
462int mei_host_client_properties(struct mei_device *dev)
463{
464	struct mei_msg_hdr *mei_header;
465	struct hbm_props_request *host_cli_req;
466	int b;
467	u8 client_num = dev->me_client_presentation_num;
468
469	b = dev->me_client_index;
470	b = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX, b);
471	if (b < MEI_CLIENTS_MAX) {
472		dev->me_clients[client_num].client_id = b;
473		dev->me_clients[client_num].mei_flow_ctrl_creds = 0;
474		mei_header = (struct mei_msg_hdr *)&dev->wr_msg_buf[0];
475		mei_header->host_addr = 0;
476		mei_header->me_addr = 0;
477		mei_header->length = sizeof(struct hbm_props_request);
478		mei_header->msg_complete = 1;
479		mei_header->reserved = 0;
480
481		host_cli_req = (struct hbm_props_request *)&dev->wr_msg_buf[1];
482
483		memset(host_cli_req, 0, sizeof(struct hbm_props_request));
484
485		host_cli_req->hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
486		host_cli_req->address = b;
487
488		if (mei_write_message(dev, mei_header,
489				(unsigned char *)host_cli_req,
490				mei_header->length)) {
491			dev->mei_state = MEI_RESETING;
492			dev_dbg(&dev->pdev->dev, "write send enumeration request message to FW fail.\n");
493			mei_reset(dev, 1);
494			return -EIO;
495		}
496
497		dev->init_clients_timer = INIT_CLIENTS_TIMEOUT;
498		dev->me_client_index = b;
499		return 1;
500	}
501
502	return 0;
503}
504
505/**
506 * mei_init_file_private - initializes private file structure.
507 *
508 * @priv: private file structure to be initialized
509 * @file: the file structure
510 */
511void mei_cl_init(struct mei_cl *priv, struct mei_device *dev)
512{
513	memset(priv, 0, sizeof(struct mei_cl));
514	init_waitqueue_head(&priv->wait);
515	init_waitqueue_head(&priv->rx_wait);
516	init_waitqueue_head(&priv->tx_wait);
517	INIT_LIST_HEAD(&priv->link);
518	priv->reading_state = MEI_IDLE;
519	priv->writing_state = MEI_IDLE;
520	priv->dev = dev;
521}
522
523int mei_find_me_client_index(const struct mei_device *dev, uuid_le cuuid)
524{
525	int i, res = -1;
526
527	for (i = 0; i < dev->me_clients_num; ++i)
528		if (uuid_le_cmp(cuuid,
529				dev->me_clients[i].props.protocol_name) == 0) {
530			res = i;
531			break;
532		}
533
534	return res;
535}
536
537
538/**
539 * mei_find_me_client_update_filext - searches for ME client guid
540 *                       sets client_id in mei_file_private if found
541 * @dev: the device structure
542 * @priv: private file structure to set client_id in
543 * @cguid: searched guid of ME client
544 * @client_id: id of host client to be set in file private structure
545 *
546 * returns ME client index
547 */
548u8 mei_find_me_client_update_filext(struct mei_device *dev, struct mei_cl *priv,
549				const uuid_le *cguid, u8 client_id)
550{
551	int i;
552
553	if (!dev || !priv || !cguid)
554		return 0;
555
556	/* check for valid client id */
557	i = mei_find_me_client_index(dev, *cguid);
558	if (i >= 0) {
559		priv->me_client_id = dev->me_clients[i].client_id;
560		priv->state = MEI_FILE_CONNECTING;
561		priv->host_client_id = client_id;
562
563		list_add_tail(&priv->link, &dev->file_list);
564		return (u8)i;
565	}
566
567	return 0;
568}
569
570/**
571 * host_init_iamthif - mei initialization iamthif client.
572 *
573 * @dev: the device structure
574 *
575 */
576void mei_host_init_iamthif(struct mei_device *dev)
577{
578	u8 i;
579	unsigned char *msg_buf;
580
581	mei_cl_init(&dev->iamthif_cl, dev);
582	dev->iamthif_cl.state = MEI_FILE_DISCONNECTED;
583
584	/* find ME amthi client */
585	i = mei_find_me_client_update_filext(dev, &dev->iamthif_cl,
586			    &mei_amthi_guid, MEI_IAMTHIF_HOST_CLIENT_ID);
587	if (dev->iamthif_cl.state != MEI_FILE_CONNECTING) {
588		dev_dbg(&dev->pdev->dev, "failed to find iamthif client.\n");
589		return;
590	}
591
592	/* Assign iamthif_mtu to the value received from ME  */
593
594	dev->iamthif_mtu = dev->me_clients[i].props.max_msg_length;
595	dev_dbg(&dev->pdev->dev, "IAMTHIF_MTU = %d\n",
596			dev->me_clients[i].props.max_msg_length);
597
598	kfree(dev->iamthif_msg_buf);
599	dev->iamthif_msg_buf = NULL;
600
601	/* allocate storage for ME message buffer */
602	msg_buf = kcalloc(dev->iamthif_mtu,
603			sizeof(unsigned char), GFP_KERNEL);
604	if (!msg_buf) {
605		dev_dbg(&dev->pdev->dev, "memory allocation for ME message buffer failed.\n");
606		return;
607	}
608
609	dev->iamthif_msg_buf = msg_buf;
610
611	if (mei_connect(dev, &dev->iamthif_cl)) {
612		dev_dbg(&dev->pdev->dev, "Failed to connect to AMTHI client\n");
613		dev->iamthif_cl.state = MEI_FILE_DISCONNECTED;
614		dev->iamthif_cl.host_client_id = 0;
615	} else {
616		dev->iamthif_cl.timer_count = CONNECT_TIMEOUT;
617	}
618}
619
620/**
621 * mei_alloc_file_private - allocates a private file structure and sets it up.
622 * @file: the file structure
623 *
624 * returns  The allocated file or NULL on failure
625 */
626struct mei_cl *mei_cl_allocate(struct mei_device *dev)
627{
628	struct mei_cl *cl;
629
630	cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
631	if (!cl)
632		return NULL;
633
634	mei_cl_init(cl, dev);
635
636	return cl;
637}
638
639
640
641/**
642 * mei_disconnect_host_client - sends disconnect message to fw from host client.
643 *
644 * @dev: the device structure
645 * @cl: private data of the file object
646 *
647 * Locking: called under "dev->device_lock" lock
648 *
649 * returns 0 on success, <0 on failure.
650 */
651int mei_disconnect_host_client(struct mei_device *dev, struct mei_cl *cl)
652{
653	int rets, err;
654	long timeout = 15;	/* 15 seconds */
655	struct mei_cl_cb *cb;
656
657	if (!dev || !cl)
658		return -ENODEV;
659
660	if (cl->state != MEI_FILE_DISCONNECTING)
661		return 0;
662
663	cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
664	if (!cb)
665		return -ENOMEM;
666
667	INIT_LIST_HEAD(&cb->cb_list);
668	cb->file_private = cl;
669	cb->major_file_operations = MEI_CLOSE;
670	if (dev->mei_host_buffer_is_empty) {
671		dev->mei_host_buffer_is_empty = false;
672		if (mei_disconnect(dev, cl)) {
673			rets = -ENODEV;
674			dev_dbg(&dev->pdev->dev, "failed to call mei_disconnect.\n");
675			goto free;
676		}
677		mdelay(10); /* Wait for hardware disconnection ready */
678		list_add_tail(&cb->cb_list, &dev->ctrl_rd_list.mei_cb.cb_list);
679	} else {
680		dev_dbg(&dev->pdev->dev, "add disconnect cb to control write list\n");
681		list_add_tail(&cb->cb_list,
682				&dev->ctrl_wr_list.mei_cb.cb_list);
683	}
684	mutex_unlock(&dev->device_lock);
685
686	err = wait_event_timeout(dev->wait_recvd_msg,
687		 (MEI_FILE_DISCONNECTED == cl->state),
688		 timeout * HZ);
689
690	mutex_lock(&dev->device_lock);
691	if (MEI_FILE_DISCONNECTED == cl->state) {
692		rets = 0;
693		dev_dbg(&dev->pdev->dev, "successfully disconnected from FW client.\n");
694	} else {
695		rets = -ENODEV;
696		if (MEI_FILE_DISCONNECTED != cl->state)
697			dev_dbg(&dev->pdev->dev, "wrong status client disconnect.\n");
698
699		if (err)
700			dev_dbg(&dev->pdev->dev,
701					"wait failed disconnect err=%08x\n",
702					err);
703
704		dev_dbg(&dev->pdev->dev, "failed to disconnect from FW client.\n");
705	}
706
707	mei_io_list_flush(&dev->ctrl_rd_list, cl);
708	mei_io_list_flush(&dev->ctrl_wr_list, cl);
709free:
710	mei_free_cb_private(cb);
711	return rets;
712}
713
714/**
715 * mei_remove_client_from_file_list -
716 *	removes file private data from device file list
717 *
718 * @dev: the device structure
719 * @host_client_id: host client id to be removed
720 */
721void mei_remove_client_from_file_list(struct mei_device *dev,
722				       u8 host_client_id)
723{
724	struct mei_cl *cl_pos = NULL;
725	struct mei_cl *cl_next = NULL;
726	list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
727		if (host_client_id == cl_pos->host_client_id) {
728			dev_dbg(&dev->pdev->dev, "remove host client = %d, ME client = %d\n",
729					cl_pos->host_client_id,
730					cl_pos->me_client_id);
731			list_del_init(&cl_pos->link);
732			break;
733		}
734	}
735}
736