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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright (c) 2012-2022, Intel Corporation. All rights reserved.
  4 * Intel Management Engine Interface (Intel MEI) Linux driver
 
 
 
 
 
 
 
 
 
 
 
  5 */
  6
  7#include <linux/export.h>
 
  8#include <linux/sched.h>
  9#include <linux/wait.h>
 10#include <linux/delay.h>
 11
 12#include <linux/mei.h>
 13
 14#include "mei_dev.h"
 15#include "hbm.h"
 16#include "client.h"
 17
 18const char *mei_dev_state_str(int state)
 19{
 20#define MEI_DEV_STATE(state) case MEI_DEV_##state: return #state
 21	switch (state) {
 22	MEI_DEV_STATE(INITIALIZING);
 23	MEI_DEV_STATE(INIT_CLIENTS);
 24	MEI_DEV_STATE(ENABLED);
 25	MEI_DEV_STATE(RESETTING);
 26	MEI_DEV_STATE(DISABLED);
 27	MEI_DEV_STATE(POWERING_DOWN);
 28	MEI_DEV_STATE(POWER_DOWN);
 29	MEI_DEV_STATE(POWER_UP);
 30	default:
 31		return "unknown";
 32	}
 33#undef MEI_DEV_STATE
 34}
 35
 36const char *mei_pg_state_str(enum mei_pg_state state)
 37{
 38#define MEI_PG_STATE(state) case MEI_PG_##state: return #state
 39	switch (state) {
 40	MEI_PG_STATE(OFF);
 41	MEI_PG_STATE(ON);
 42	default:
 43		return "unknown";
 44	}
 45#undef MEI_PG_STATE
 46}
 47
 48/**
 49 * mei_fw_status2str - convert fw status registers to printable string
 50 *
 51 * @fw_status:  firmware status
 52 * @buf: string buffer at minimal size MEI_FW_STATUS_STR_SZ
 53 * @len: buffer len must be >= MEI_FW_STATUS_STR_SZ
 54 *
 55 * Return: number of bytes written or -EINVAL if buffer is to small
 56 */
 57ssize_t mei_fw_status2str(struct mei_fw_status *fw_status,
 58			  char *buf, size_t len)
 59{
 60	ssize_t cnt = 0;
 61	int i;
 62
 63	buf[0] = '\0';
 64
 65	if (len < MEI_FW_STATUS_STR_SZ)
 66		return -EINVAL;
 67
 68	for (i = 0; i < fw_status->count; i++)
 69		cnt += scnprintf(buf + cnt, len - cnt, "%08X ",
 70				fw_status->status[i]);
 71
 72	/* drop last space */
 73	buf[cnt] = '\0';
 74	return cnt;
 75}
 76EXPORT_SYMBOL_GPL(mei_fw_status2str);
 77
 78/**
 79 * mei_cancel_work - Cancel mei background jobs
 80 *
 81 * @dev: the device structure
 
 
 82 */
 83void mei_cancel_work(struct mei_device *dev)
 84{
 
 85	cancel_work_sync(&dev->reset_work);
 86	cancel_work_sync(&dev->bus_rescan_work);
 87
 88	cancel_delayed_work_sync(&dev->timer_work);
 89}
 90EXPORT_SYMBOL_GPL(mei_cancel_work);
 91
 92static void mei_save_fw_status(struct mei_device *dev)
 93{
 94	struct mei_fw_status fw_status;
 95	int ret;
 96
 97	ret = mei_fw_status(dev, &fw_status);
 98	if (ret) {
 99		dev_err(dev->dev, "failed to read firmware status: %d\n", ret);
100		return;
101	}
102
103	dev->saved_dev_state = dev->dev_state;
104	dev->saved_fw_status_flag = true;
105	memcpy(&dev->saved_fw_status, &fw_status, sizeof(fw_status));
106}
107
108/**
109 * mei_reset - resets host and fw.
110 *
111 * @dev: the device structure
112 *
113 * Return: 0 on success or < 0 if the reset hasn't succeeded
114 */
115int mei_reset(struct mei_device *dev)
116{
117	enum mei_dev_state state = dev->dev_state;
118	bool interrupts_enabled;
119	int ret;
120
121	if (state != MEI_DEV_INITIALIZING &&
122	    state != MEI_DEV_DISABLED &&
123	    state != MEI_DEV_POWER_DOWN &&
124	    state != MEI_DEV_POWER_UP) {
125		char fw_sts_str[MEI_FW_STATUS_STR_SZ];
126
127		mei_fw_status_str(dev, fw_sts_str, MEI_FW_STATUS_STR_SZ);
128		if (kind_is_gsc(dev) || kind_is_gscfi(dev)) {
129			dev_dbg(dev->dev, "unexpected reset: dev_state = %s fw status = %s\n",
130				mei_dev_state_str(state), fw_sts_str);
131			mei_save_fw_status(dev);
132		} else {
133			dev_warn(dev->dev, "unexpected reset: dev_state = %s fw status = %s\n",
134				 mei_dev_state_str(state), fw_sts_str);
135		}
136	}
137
138	mei_clear_interrupts(dev);
139
140	/* we're already in reset, cancel the init timer
141	 * if the reset was called due the hbm protocol error
142	 * we need to call it before hw start
143	 * so the hbm watchdog won't kick in
144	 */
145	mei_hbm_idle(dev);
146
147	/* enter reset flow */
148	interrupts_enabled = state != MEI_DEV_POWER_DOWN;
149	mei_set_devstate(dev, MEI_DEV_RESETTING);
150
151	dev->reset_count++;
152	if (dev->reset_count > MEI_MAX_CONSEC_RESET) {
153		dev_err(dev->dev, "reset: reached maximal consecutive resets: disabling the device\n");
154		mei_set_devstate(dev, MEI_DEV_DISABLED);
155		return -ENODEV;
156	}
157
158	ret = mei_hw_reset(dev, interrupts_enabled);
159	/* fall through and remove the sw state even if hw reset has failed */
160
161	/* no need to clean up software state in case of power up */
162	if (state != MEI_DEV_INITIALIZING && state != MEI_DEV_POWER_UP)
 
 
 
 
 
163		mei_cl_all_disconnect(dev);
164
165	mei_hbm_reset(dev);
 
 
 
 
 
 
 
 
166
167	/* clean stale FW version */
168	dev->fw_ver_received = 0;
169
170	memset(dev->rd_msg_hdr, 0, sizeof(dev->rd_msg_hdr));
 
 
171
172	if (ret) {
173		dev_err(dev->dev, "hw_reset failed ret = %d\n", ret);
174		return ret;
175	}
176
177	if (state == MEI_DEV_POWER_DOWN) {
178		dev_dbg(dev->dev, "powering down: end of reset\n");
179		mei_set_devstate(dev, MEI_DEV_DISABLED);
180		return 0;
181	}
182
183	ret = mei_hw_start(dev);
184	if (ret) {
185		char fw_sts_str[MEI_FW_STATUS_STR_SZ];
186
187		mei_fw_status_str(dev, fw_sts_str, MEI_FW_STATUS_STR_SZ);
188		dev_err(dev->dev, "hw_start failed ret = %d fw status = %s\n", ret, fw_sts_str);
189		return ret;
190	}
191
192	if (dev->dev_state != MEI_DEV_RESETTING) {
193		dev_dbg(dev->dev, "wrong state = %d on link start\n", dev->dev_state);
194		return 0;
195	}
196
197	dev_dbg(dev->dev, "link is established start sending messages.\n");
198
199	mei_set_devstate(dev, MEI_DEV_INIT_CLIENTS);
200	ret = mei_hbm_start_req(dev);
201	if (ret) {
202		dev_err(dev->dev, "hbm_start failed ret = %d\n", ret);
203		mei_set_devstate(dev, MEI_DEV_RESETTING);
204		return ret;
205	}
206
207	return 0;
208}
209EXPORT_SYMBOL_GPL(mei_reset);
210
211/**
212 * mei_start - initializes host and fw to start work.
213 *
214 * @dev: the device structure
215 *
216 * Return: 0 on success, <0 on failure.
217 */
218int mei_start(struct mei_device *dev)
219{
220	int ret;
221
222	mutex_lock(&dev->device_lock);
223
224	/* acknowledge interrupt and stop interrupts */
225	mei_clear_interrupts(dev);
226
227	ret = mei_hw_config(dev);
228	if (ret)
229		goto err;
230
231	dev_dbg(dev->dev, "reset in start the mei device.\n");
232
233	dev->reset_count = 0;
234	do {
235		mei_set_devstate(dev, MEI_DEV_INITIALIZING);
236		ret = mei_reset(dev);
237
238		if (ret == -ENODEV || dev->dev_state == MEI_DEV_DISABLED) {
239			dev_err(dev->dev, "reset failed ret = %d", ret);
240			goto err;
241		}
242	} while (ret);
243
 
 
 
 
 
 
244	if (mei_hbm_start_wait(dev)) {
245		dev_err(dev->dev, "HBM haven't started");
 
 
 
 
 
 
 
 
 
 
246		goto err;
247	}
248
249	if (!mei_hbm_version_is_supported(dev)) {
250		dev_dbg(dev->dev, "MEI start failed.\n");
251		goto err;
252	}
253
254	dev_dbg(dev->dev, "link layer has been established.\n");
255
256	mutex_unlock(&dev->device_lock);
257	return 0;
258err:
259	dev_err(dev->dev, "link layer initialization failed.\n");
260	mei_set_devstate(dev, MEI_DEV_DISABLED);
261	mutex_unlock(&dev->device_lock);
262	return -ENODEV;
263}
264EXPORT_SYMBOL_GPL(mei_start);
265
266/**
267 * mei_restart - restart device after suspend
268 *
269 * @dev: the device structure
270 *
271 * Return: 0 on success or -ENODEV if the restart hasn't succeeded
272 */
273int mei_restart(struct mei_device *dev)
274{
275	int err;
276
277	mutex_lock(&dev->device_lock);
278
279	mei_set_devstate(dev, MEI_DEV_POWER_UP);
 
 
280	dev->reset_count = 0;
281
282	err = mei_reset(dev);
283
284	mutex_unlock(&dev->device_lock);
285
286	if (err == -ENODEV || dev->dev_state == MEI_DEV_DISABLED) {
287		dev_err(dev->dev, "device disabled = %d\n", err);
288		return -ENODEV;
289	}
290
291	/* try to start again */
292	if (err)
293		schedule_work(&dev->reset_work);
294
295
296	return 0;
297}
298EXPORT_SYMBOL_GPL(mei_restart);
299
300static void mei_reset_work(struct work_struct *work)
301{
302	struct mei_device *dev =
303		container_of(work, struct mei_device,  reset_work);
304	int ret;
305
306	mei_clear_interrupts(dev);
307	mei_synchronize_irq(dev);
308
309	mutex_lock(&dev->device_lock);
310
311	ret = mei_reset(dev);
312
313	mutex_unlock(&dev->device_lock);
314
315	if (dev->dev_state == MEI_DEV_DISABLED) {
316		dev_err(dev->dev, "device disabled = %d\n", ret);
317		return;
318	}
319
320	/* retry reset in case of failure */
321	if (ret)
322		schedule_work(&dev->reset_work);
323}
324
325void mei_stop(struct mei_device *dev)
326{
327	dev_dbg(dev->dev, "stopping the device.\n");
328
329	mutex_lock(&dev->device_lock);
330	mei_set_devstate(dev, MEI_DEV_POWERING_DOWN);
331	mutex_unlock(&dev->device_lock);
332	mei_cl_bus_remove_devices(dev);
333	mutex_lock(&dev->device_lock);
334	mei_set_devstate(dev, MEI_DEV_POWER_DOWN);
335	mutex_unlock(&dev->device_lock);
336
337	mei_cancel_work(dev);
338
339	mei_clear_interrupts(dev);
340	mei_synchronize_irq(dev);
341	/* to catch HW-initiated reset */
342	mei_cancel_work(dev);
343
344	mutex_lock(&dev->device_lock);
345
 
 
 
346	mei_reset(dev);
347	/* move device to disabled state unconditionally */
348	mei_set_devstate(dev, MEI_DEV_DISABLED);
349
350	mutex_unlock(&dev->device_lock);
 
 
351}
352EXPORT_SYMBOL_GPL(mei_stop);
353
354/**
355 * mei_write_is_idle - check if the write queues are idle
356 *
357 * @dev: the device structure
358 *
359 * Return: true of there is no pending write
360 */
361bool mei_write_is_idle(struct mei_device *dev)
362{
363	bool idle = (dev->dev_state == MEI_DEV_ENABLED &&
364		list_empty(&dev->ctrl_wr_list) &&
365		list_empty(&dev->write_list)   &&
366		list_empty(&dev->write_waiting_list));
367
368	dev_dbg(dev->dev, "write pg: is idle[%d] state=%s ctrl=%01d write=%01d wwait=%01d\n",
369		idle,
370		mei_dev_state_str(dev->dev_state),
371		list_empty(&dev->ctrl_wr_list),
372		list_empty(&dev->write_list),
373		list_empty(&dev->write_waiting_list));
374
375	return idle;
376}
377EXPORT_SYMBOL_GPL(mei_write_is_idle);
378
379/**
380 * mei_device_init - initialize mei_device structure
381 *
382 * @dev: the mei device
383 * @device: the device structure
384 * @slow_fw: configure longer timeouts as FW is slow
385 * @hw_ops: hw operations
386 */
387void mei_device_init(struct mei_device *dev,
388		     struct device *device,
389		     bool slow_fw,
390		     const struct mei_hw_ops *hw_ops)
391{
392	/* setup our list array */
393	INIT_LIST_HEAD(&dev->file_list);
394	INIT_LIST_HEAD(&dev->device_list);
395	INIT_LIST_HEAD(&dev->me_clients);
396	mutex_init(&dev->device_lock);
397	init_rwsem(&dev->me_clients_rwsem);
398	mutex_init(&dev->cl_bus_lock);
399	init_waitqueue_head(&dev->wait_hw_ready);
400	init_waitqueue_head(&dev->wait_pg);
401	init_waitqueue_head(&dev->wait_hbm_start);
402	dev->dev_state = MEI_DEV_INITIALIZING;
403	dev->reset_count = 0;
404
405	INIT_LIST_HEAD(&dev->write_list);
406	INIT_LIST_HEAD(&dev->write_waiting_list);
407	INIT_LIST_HEAD(&dev->ctrl_wr_list);
408	INIT_LIST_HEAD(&dev->ctrl_rd_list);
409	dev->tx_queue_limit = MEI_TX_QUEUE_LIMIT_DEFAULT;
410
411	INIT_DELAYED_WORK(&dev->timer_work, mei_timer);
 
412	INIT_WORK(&dev->reset_work, mei_reset_work);
413	INIT_WORK(&dev->bus_rescan_work, mei_cl_bus_rescan_work);
 
 
 
 
414
415	bitmap_zero(dev->host_clients_map, MEI_CLIENTS_MAX);
416	dev->open_handle_count = 0;
417
418	dev->pxp_mode = MEI_DEV_PXP_DEFAULT;
419	dev->gsc_reset_to_pxp = MEI_DEV_RESET_TO_PXP_DEFAULT;
420
421	/*
422	 * Reserving the first client ID
423	 * 0: Reserved for MEI Bus Message communications
424	 */
425	bitmap_set(dev->host_clients_map, 0, 1);
426
427	dev->pg_event = MEI_PG_EVENT_IDLE;
428	dev->ops      = hw_ops;
429	dev->dev      = device;
430
431	dev->timeouts.hw_ready = mei_secs_to_jiffies(MEI_HW_READY_TIMEOUT);
432	dev->timeouts.connect = MEI_CONNECT_TIMEOUT;
433	dev->timeouts.client_init = MEI_CLIENTS_INIT_TIMEOUT;
434	dev->timeouts.pgi = mei_secs_to_jiffies(MEI_PGI_TIMEOUT);
435	dev->timeouts.d0i3 = mei_secs_to_jiffies(MEI_D0I3_TIMEOUT);
436	if (slow_fw) {
437		dev->timeouts.cl_connect = mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT_SLOW);
438		dev->timeouts.hbm = mei_secs_to_jiffies(MEI_HBM_TIMEOUT_SLOW);
439		dev->timeouts.mkhi_recv = msecs_to_jiffies(MKHI_RCV_TIMEOUT_SLOW);
440	} else {
441		dev->timeouts.cl_connect = mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT);
442		dev->timeouts.hbm = mei_secs_to_jiffies(MEI_HBM_TIMEOUT);
443		dev->timeouts.mkhi_recv = msecs_to_jiffies(MKHI_RCV_TIMEOUT);
444	}
445}
446EXPORT_SYMBOL_GPL(mei_device_init);
447
v3.15
 
  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/export.h>
 18#include <linux/pci.h>
 19#include <linux/sched.h>
 20#include <linux/wait.h>
 21#include <linux/delay.h>
 22
 23#include <linux/mei.h>
 24
 25#include "mei_dev.h"
 26#include "hbm.h"
 27#include "client.h"
 28
 29const char *mei_dev_state_str(int state)
 30{
 31#define MEI_DEV_STATE(state) case MEI_DEV_##state: return #state
 32	switch (state) {
 33	MEI_DEV_STATE(INITIALIZING);
 34	MEI_DEV_STATE(INIT_CLIENTS);
 35	MEI_DEV_STATE(ENABLED);
 36	MEI_DEV_STATE(RESETTING);
 37	MEI_DEV_STATE(DISABLED);
 
 38	MEI_DEV_STATE(POWER_DOWN);
 39	MEI_DEV_STATE(POWER_UP);
 40	default:
 41		return "unknown";
 42	}
 43#undef MEI_DEV_STATE
 44}
 45
 
 
 
 
 
 
 
 
 
 
 
 46
 47/**
 48 * mei_cancel_work. Cancel mei background jobs
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 49 *
 50 * @dev: the device structure
 51 *
 52 * returns 0 on success or < 0 if the reset hasn't succeeded
 53 */
 54void mei_cancel_work(struct mei_device *dev)
 55{
 56	cancel_work_sync(&dev->init_work);
 57	cancel_work_sync(&dev->reset_work);
 
 58
 59	cancel_delayed_work(&dev->timer_work);
 60}
 61EXPORT_SYMBOL_GPL(mei_cancel_work);
 62
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 63/**
 64 * mei_reset - resets host and fw.
 65 *
 66 * @dev: the device structure
 
 
 67 */
 68int mei_reset(struct mei_device *dev)
 69{
 70	enum mei_dev_state state = dev->dev_state;
 71	bool interrupts_enabled;
 72	int ret;
 73
 74	if (state != MEI_DEV_INITIALIZING &&
 75	    state != MEI_DEV_DISABLED &&
 76	    state != MEI_DEV_POWER_DOWN &&
 77	    state != MEI_DEV_POWER_UP)
 78		dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
 79			 mei_dev_state_str(state));
 
 
 
 
 
 
 
 
 
 
 
 
 80
 81	/* we're already in reset, cancel the init timer
 82	 * if the reset was called due the hbm protocol error
 83	 * we need to call it before hw start
 84	 * so the hbm watchdog won't kick in
 85	 */
 86	mei_hbm_idle(dev);
 87
 88	/* enter reset flow */
 89	interrupts_enabled = state != MEI_DEV_POWER_DOWN;
 90	dev->dev_state = MEI_DEV_RESETTING;
 91
 92	dev->reset_count++;
 93	if (dev->reset_count > MEI_MAX_CONSEC_RESET) {
 94		dev_err(&dev->pdev->dev, "reset: reached maximal consecutive resets: disabling the device\n");
 95		dev->dev_state = MEI_DEV_DISABLED;
 96		return -ENODEV;
 97	}
 98
 99	ret = mei_hw_reset(dev, interrupts_enabled);
100	/* fall through and remove the sw state even if hw reset has failed */
101
102	/* no need to clean up software state in case of power up */
103	if (state != MEI_DEV_INITIALIZING &&
104	    state != MEI_DEV_POWER_UP) {
105
106		/* remove all waiting requests */
107		mei_cl_all_write_clear(dev);
108
109		mei_cl_all_disconnect(dev);
110
111		/* wake up all readers and writers so they can be interrupted */
112		mei_cl_all_wakeup(dev);
113
114		/* remove entry if already in list */
115		dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
116		mei_cl_unlink(&dev->wd_cl);
117		mei_cl_unlink(&dev->iamthif_cl);
118		mei_amthif_reset_params(dev);
119	}
120
 
 
121
122	dev->me_clients_num = 0;
123	dev->rd_msg_hdr = 0;
124	dev->wd_pending = false;
125
126	if (ret) {
127		dev_err(&dev->pdev->dev, "hw_reset failed ret = %d\n", ret);
128		return ret;
129	}
130
131	if (state == MEI_DEV_POWER_DOWN) {
132		dev_dbg(&dev->pdev->dev, "powering down: end of reset\n");
133		dev->dev_state = MEI_DEV_DISABLED;
134		return 0;
135	}
136
137	ret = mei_hw_start(dev);
138	if (ret) {
139		dev_err(&dev->pdev->dev, "hw_start failed ret = %d\n", ret);
 
 
 
140		return ret;
141	}
142
143	dev_dbg(&dev->pdev->dev, "link is established start sending messages.\n");
 
 
 
 
 
144
145	dev->dev_state = MEI_DEV_INIT_CLIENTS;
146	ret = mei_hbm_start_req(dev);
147	if (ret) {
148		dev_err(&dev->pdev->dev, "hbm_start failed ret = %d\n", ret);
149		dev->dev_state = MEI_DEV_RESETTING;
150		return ret;
151	}
152
153	return 0;
154}
155EXPORT_SYMBOL_GPL(mei_reset);
156
157/**
158 * mei_start - initializes host and fw to start work.
159 *
160 * @dev: the device structure
161 *
162 * returns 0 on success, <0 on failure.
163 */
164int mei_start(struct mei_device *dev)
165{
166	int ret;
 
167	mutex_lock(&dev->device_lock);
168
169	/* acknowledge interrupt and stop interrupts */
170	mei_clear_interrupts(dev);
171
172	mei_hw_config(dev);
 
 
173
174	dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
175
176	dev->reset_count = 0;
177	do {
178		dev->dev_state = MEI_DEV_INITIALIZING;
179		ret = mei_reset(dev);
180
181		if (ret == -ENODEV || dev->dev_state == MEI_DEV_DISABLED) {
182			dev_err(&dev->pdev->dev, "reset failed ret = %d", ret);
183			goto err;
184		}
185	} while (ret);
186
187	/* we cannot start the device w/o hbm start message completed */
188	if (dev->dev_state == MEI_DEV_DISABLED) {
189		dev_err(&dev->pdev->dev, "reset failed");
190		goto err;
191	}
192
193	if (mei_hbm_start_wait(dev)) {
194		dev_err(&dev->pdev->dev, "HBM haven't started");
195		goto err;
196	}
197
198	if (!mei_host_is_ready(dev)) {
199		dev_err(&dev->pdev->dev, "host is not ready.\n");
200		goto err;
201	}
202
203	if (!mei_hw_is_ready(dev)) {
204		dev_err(&dev->pdev->dev, "ME is not ready.\n");
205		goto err;
206	}
207
208	if (!mei_hbm_version_is_supported(dev)) {
209		dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
210		goto err;
211	}
212
213	dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
214
215	mutex_unlock(&dev->device_lock);
216	return 0;
217err:
218	dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
219	dev->dev_state = MEI_DEV_DISABLED;
220	mutex_unlock(&dev->device_lock);
221	return -ENODEV;
222}
223EXPORT_SYMBOL_GPL(mei_start);
224
225/**
226 * mei_restart - restart device after suspend
227 *
228 * @dev: the device structure
229 *
230 * returns 0 on success or -ENODEV if the restart hasn't succeeded
231 */
232int mei_restart(struct mei_device *dev)
233{
234	int err;
235
236	mutex_lock(&dev->device_lock);
237
238	mei_clear_interrupts(dev);
239
240	dev->dev_state = MEI_DEV_POWER_UP;
241	dev->reset_count = 0;
242
243	err = mei_reset(dev);
244
245	mutex_unlock(&dev->device_lock);
246
247	if (err == -ENODEV || dev->dev_state == MEI_DEV_DISABLED) {
248		dev_err(&dev->pdev->dev, "device disabled = %d\n", err);
249		return -ENODEV;
250	}
251
252	/* try to start again */
253	if (err)
254		schedule_work(&dev->reset_work);
255
256
257	return 0;
258}
259EXPORT_SYMBOL_GPL(mei_restart);
260
261static void mei_reset_work(struct work_struct *work)
262{
263	struct mei_device *dev =
264		container_of(work, struct mei_device,  reset_work);
265	int ret;
266
 
 
 
267	mutex_lock(&dev->device_lock);
268
269	ret = mei_reset(dev);
270
271	mutex_unlock(&dev->device_lock);
272
273	if (dev->dev_state == MEI_DEV_DISABLED) {
274		dev_err(&dev->pdev->dev, "device disabled = %d\n", ret);
275		return;
276	}
277
278	/* retry reset in case of failure */
279	if (ret)
280		schedule_work(&dev->reset_work);
281}
282
283void mei_stop(struct mei_device *dev)
284{
285	dev_dbg(&dev->pdev->dev, "stopping the device.\n");
 
 
 
 
 
 
 
 
286
287	mei_cancel_work(dev);
288
289	mei_nfc_host_exit(dev);
290
291	mei_cl_bus_remove_devices(dev);
 
292
293	mutex_lock(&dev->device_lock);
294
295	mei_wd_stop(dev);
296
297	dev->dev_state = MEI_DEV_POWER_DOWN;
298	mei_reset(dev);
 
 
299
300	mutex_unlock(&dev->device_lock);
301
302	mei_watchdog_unregister(dev);
303}
304EXPORT_SYMBOL_GPL(mei_stop);
305
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
306
 
 
 
307
308void mei_device_init(struct mei_device *dev)
 
 
 
 
 
 
 
 
 
 
 
309{
310	/* setup our list array */
311	INIT_LIST_HEAD(&dev->file_list);
312	INIT_LIST_HEAD(&dev->device_list);
 
313	mutex_init(&dev->device_lock);
 
 
314	init_waitqueue_head(&dev->wait_hw_ready);
315	init_waitqueue_head(&dev->wait_recvd_msg);
316	init_waitqueue_head(&dev->wait_stop_wd);
317	dev->dev_state = MEI_DEV_INITIALIZING;
318	dev->reset_count = 0;
319
320	mei_io_list_init(&dev->read_list);
321	mei_io_list_init(&dev->write_list);
322	mei_io_list_init(&dev->write_waiting_list);
323	mei_io_list_init(&dev->ctrl_wr_list);
324	mei_io_list_init(&dev->ctrl_rd_list);
325
326	INIT_DELAYED_WORK(&dev->timer_work, mei_timer);
327	INIT_WORK(&dev->init_work, mei_host_client_init);
328	INIT_WORK(&dev->reset_work, mei_reset_work);
329
330	INIT_LIST_HEAD(&dev->wd_cl.link);
331	INIT_LIST_HEAD(&dev->iamthif_cl.link);
332	mei_io_list_init(&dev->amthif_cmd_list);
333	mei_io_list_init(&dev->amthif_rd_complete_list);
334
335	bitmap_zero(dev->host_clients_map, MEI_CLIENTS_MAX);
336	dev->open_handle_count = 0;
337
 
 
 
338	/*
339	 * Reserving the first client ID
340	 * 0: Reserved for MEI Bus Message communications
341	 */
342	bitmap_set(dev->host_clients_map, 0, 1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
343}
344EXPORT_SYMBOL_GPL(mei_device_init);
345