[deliverable/linux.git] / drivers / staging / mei / wd.c

/*
 *
 * Intel Management Engine Interface (Intel MEI) Linux driver
 * Copyright (c) 2003-2011, Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/device.h>
#include <linux/pci.h>
#include <linux/sched.h>
#include <linux/watchdog.h>

#include "mei_dev.h"
#include "hw.h"
#include "interface.h"
#include "mei.h"

/*
 * MEI Watchdog Module Parameters
 */
static u16 watchdog_timeout = AMT_WD_DEFAULT_TIMEOUT;
module_param(watchdog_timeout, ushort, 0);
MODULE_PARM_DESC(watchdog_timeout,
		"Intel(R) AMT Watchdog timeout value in seconds. (default="
					__MODULE_STRING(AMT_WD_DEFAULT_TIMEOUT)
					", disable=0)");

static const u8 mei_start_wd_params[] = { 0x02, 0x12, 0x13, 0x10 };
static const u8 mei_stop_wd_params[] = { 0x02, 0x02, 0x14, 0x10 };

const u8 mei_wd_state_independence_msg[3][4] = {
	{0x05, 0x02, 0x51, 0x10},
	{0x05, 0x02, 0x52, 0x10},
	{0x07, 0x02, 0x01, 0x10}
};

/* UUIDs for AMT F/W clients */
const uuid_le mei_wd_guid = UUID_LE(0x05B79A6F, 0x4628, 0x4D7F, 0x89,
						0x9D, 0xA9, 0x15, 0x14, 0xCB,
						0x32, 0xAB);


void mei_wd_set_start_timeout(struct mei_device *dev, u16 timeout)
{
	dev_dbg(&dev->pdev->dev, "timeout=%d.\n", timeout);
	memcpy(dev->wd_data, mei_start_wd_params, MEI_WD_PARAMS_SIZE);
	memcpy(dev->wd_data + MEI_WD_PARAMS_SIZE,
			&timeout, sizeof(u16));
}

/**
 * host_init_wd - mei initialization wd.
 *
 * @dev: the device structure
 */
bool mei_wd_host_init(struct mei_device *dev)
{
	bool ret = false;

	mei_cl_init(&dev->wd_cl, dev);

	/* look for WD client and connect to it */
	dev->wd_cl.state = MEI_FILE_DISCONNECTED;
	dev->wd_timeout = watchdog_timeout;

	if (dev->wd_timeout > 0) {
		/* find ME WD client */
		mei_find_me_client_update_filext(dev, &dev->wd_cl,
					&mei_wd_guid, MEI_WD_HOST_CLIENT_ID);

		dev_dbg(&dev->pdev->dev, "check wd_cl\n");
		if (MEI_FILE_CONNECTING == dev->wd_cl.state) {
			if (!mei_connect(dev, &dev->wd_cl)) {
				dev_dbg(&dev->pdev->dev, "Failed to connect to WD client\n");
				dev->wd_cl.state = MEI_FILE_DISCONNECTED;
				dev->wd_cl.host_client_id = 0;
				ret = false;
				goto end;
			} else {
				dev->wd_cl.timer_count = CONNECT_TIMEOUT;
			}
		} else {
			dev_dbg(&dev->pdev->dev, "Failed to find WD client\n");
			ret = false;
			goto end;
		}
	} else {
		dev->wd_bypass = true;
		dev_dbg(&dev->pdev->dev, "WD requested to be disabled\n");
		ret = false;
		goto end;
	}

end:
	return ret;
}

/**
 * mei_wd_send - sends watch dog message to fw.
 *
 * @dev: the device structure
 *
 * returns 0 if success,
 *	-EIO when message send fails
 *	-EINVAL when invalid message is to be sent
 */
int mei_wd_send(struct mei_device *dev)
{
	struct mei_msg_hdr *mei_hdr;

	mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
	mei_hdr->host_addr = dev->wd_cl.host_client_id;
	mei_hdr->me_addr = dev->wd_cl.me_client_id;
	mei_hdr->msg_complete = 1;
	mei_hdr->reserved = 0;

	if (!memcmp(dev->wd_data, mei_start_wd_params, MEI_WD_PARAMS_SIZE))
		mei_hdr->length = MEI_START_WD_DATA_SIZE;
	else if (!memcmp(dev->wd_data, mei_stop_wd_params, MEI_WD_PARAMS_SIZE))
		mei_hdr->length = MEI_WD_PARAMS_SIZE;
	else
		return -EINVAL;

	if (mei_write_message(dev, mei_hdr, dev->wd_data, mei_hdr->length))
		return 0;
	return -EIO;
}

int mei_wd_stop(struct mei_device *dev, bool preserve)
{
	int ret;
	u16 wd_timeout = dev->wd_timeout;

	cancel_delayed_work(&dev->timer_work);
	if (dev->wd_cl.state != MEI_FILE_CONNECTED || !dev->wd_timeout)
		return 0;

	dev->wd_timeout = 0;
	dev->wd_due_counter = 0;
	memcpy(dev->wd_data, mei_stop_wd_params, MEI_WD_PARAMS_SIZE);
	dev->stop = true;

	ret = mei_flow_ctrl_creds(dev, &dev->wd_cl);
	if (ret < 0)
		goto out;

	if (ret && dev->mei_host_buffer_is_empty) {
		ret = 0;
		dev->mei_host_buffer_is_empty = false;

		if (!mei_wd_send(dev)) {
			ret = mei_flow_ctrl_reduce(dev, &dev->wd_cl);
			if (ret)
				goto out;
		} else {
			dev_dbg(&dev->pdev->dev, "send stop WD failed\n");
		}

		dev->wd_pending = false;
	} else {
		dev->wd_pending = true;
	}
	dev->wd_stopped = false;
	mutex_unlock(&dev->device_lock);

	ret = wait_event_interruptible_timeout(dev->wait_stop_wd,
					dev->wd_stopped, 10 * HZ);
	mutex_lock(&dev->device_lock);
	if (dev->wd_stopped) {
		dev_dbg(&dev->pdev->dev, "stop wd complete ret=%d.\n", ret);
		ret = 0;
	} else {
		if (!ret)
			ret = -ETIMEDOUT;
		dev_warn(&dev->pdev->dev,
			"stop wd failed to complete ret=%d.\n", ret);
	}

	if (preserve)
		dev->wd_timeout = wd_timeout;

out:
	return ret;
}

/*
 * mei_wd_ops_start - wd start command from the watchdog core.
 *
 * @wd_dev - watchdog device struct
 *
 * returns 0 if success, negative errno code for failure
 */
static int mei_wd_ops_start(struct watchdog_device *wd_dev)
{
	int err = -ENODEV;
	struct mei_device *dev;

	dev = pci_get_drvdata(mei_device);
	if (!dev)
		return -ENODEV;

	mutex_lock(&dev->device_lock);

	if (dev->mei_state != MEI_ENABLED) {
		dev_dbg(&dev->pdev->dev, "mei_state != MEI_ENABLED  mei_state= %d\n",
		    dev->mei_state);
		goto end_unlock;
	}

	if (dev->wd_cl.state != MEI_FILE_CONNECTED)	{
		dev_dbg(&dev->pdev->dev, "MEI Driver is not connected to Watchdog Client\n");
		goto end_unlock;
	}

	mei_wd_set_start_timeout(dev, dev->wd_timeout);

	err = 0;
end_unlock:
	mutex_unlock(&dev->device_lock);
	return err;
}

/*
 * mei_wd_ops_stop -  wd stop command from the watchdog core.
 *
 * @wd_dev - watchdog device struct
 *
 * returns 0 if success, negative errno code for failure
 */
static int mei_wd_ops_stop(struct watchdog_device *wd_dev)
{
	struct mei_device *dev;
	dev = pci_get_drvdata(mei_device);

	if (!dev)
		return -ENODEV;

	mutex_lock(&dev->device_lock);
	mei_wd_stop(dev, false);
	mutex_unlock(&dev->device_lock);

	return 0;
}

/*
 * mei_wd_ops_ping - wd ping command from the watchdog core.
 *
 * @wd_dev - watchdog device struct
 *
 * returns 0 if success, negative errno code for failure
 */
static int mei_wd_ops_ping(struct watchdog_device *wd_dev)
{
	int ret = 0;
	struct mei_device *dev;
	dev = pci_get_drvdata(mei_device);

	if (!dev)
		return -ENODEV;

	mutex_lock(&dev->device_lock);

	if (dev->wd_cl.state != MEI_FILE_CONNECTED) {
		dev_dbg(&dev->pdev->dev, "wd is not connected.\n");
		ret = -ENODEV;
		goto end;
	}

	/* Check if we can send the ping to HW*/
	if (dev->mei_host_buffer_is_empty &&
		mei_flow_ctrl_creds(dev, &dev->wd_cl) > 0) {

		dev->mei_host_buffer_is_empty = false;
		dev_dbg(&dev->pdev->dev, "sending watchdog ping\n");

		if (mei_wd_send(dev)) {
			dev_dbg(&dev->pdev->dev, "wd send failed.\n");
			ret = -EIO;
			goto end;
		}

		if (mei_flow_ctrl_reduce(dev, &dev->wd_cl)) {
			dev_dbg(&dev->pdev->dev, "mei_flow_ctrl_reduce() failed.\n");
			ret = -EIO;
			goto end;
		}

	} else {
		dev->wd_pending = true;
	}

end:
	mutex_unlock(&dev->device_lock);
	return ret;
}

/*
 * mei_wd_ops_set_timeout - wd set timeout command from the watchdog core.
 *
 * @wd_dev - watchdog device struct
 * @timeout - timeout value to set
 *
 * returns 0 if success, negative errno code for failure
 */
static int mei_wd_ops_set_timeout(struct watchdog_device *wd_dev, unsigned int timeout)
{
	struct mei_device *dev;
	dev = pci_get_drvdata(mei_device);

	if (!dev)
		return -ENODEV;

	/* Check Timeout value */
	if (timeout < AMT_WD_MIN_TIMEOUT || timeout > AMT_WD_MAX_TIMEOUT)
		return -EINVAL;

	mutex_lock(&dev->device_lock);

	dev->wd_timeout = timeout;
	mei_wd_set_start_timeout(dev, dev->wd_timeout);

	mutex_unlock(&dev->device_lock);

	return 0;
}

/*
 * Watchdog Device structs
 */
const struct watchdog_ops wd_ops = {
		.owner = THIS_MODULE,
		.start = mei_wd_ops_start,
		.stop = mei_wd_ops_stop,
		.ping = mei_wd_ops_ping,
		.set_timeout = mei_wd_ops_set_timeout,
};
const struct watchdog_info wd_info = {
		.identity = INTEL_AMT_WATCHDOG_ID,
		.options = WDIOF_KEEPALIVEPING,
};

struct watchdog_device amt_wd_dev = {
		.info = &wd_info,
		.ops = &wd_ops,
		.timeout = AMT_WD_DEFAULT_TIMEOUT,
		.min_timeout = AMT_WD_MIN_TIMEOUT,
		.max_timeout = AMT_WD_MAX_TIMEOUT,
};
Commit	Line	Data
3ceb3e66 OW	1	/*
	2	*
	3	* Intel Management Engine Interface (Intel MEI) Linux driver
	4	* Copyright (c) 2003-2011, 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/kernel.h>
	17	#include <linux/module.h>
	18	#include <linux/moduleparam.h>
	19	#include <linux/device.h>
	20	#include <linux/pci.h>
	21	#include <linux/sched.h>
9ce178e5	22	#include <linux/watchdog.h>
3ceb3e66 OW	23
	24	#include "mei_dev.h"
	25	#include "hw.h"
	26	#include "interface.h"
	27	#include "mei.h"
	28
	29	/*
	30	* MEI Watchdog Module Parameters
	31	*/
9ce178e5	32	static u16 watchdog_timeout = AMT_WD_DEFAULT_TIMEOUT;
3ceb3e66 OW	33	module_param(watchdog_timeout, ushort, 0);
	34	MODULE_PARM_DESC(watchdog_timeout,
	35	"Intel(R) AMT Watchdog timeout value in seconds. (default="
9ce178e5	36	__MODULE_STRING(AMT_WD_DEFAULT_TIMEOUT)
3ceb3e66 OW	37	", disable=0)");
	38
	39	static const u8 mei_start_wd_params[] = { 0x02, 0x12, 0x13, 0x10 };
	40	static const u8 mei_stop_wd_params[] = { 0x02, 0x02, 0x14, 0x10 };
	41
	42	const u8 mei_wd_state_independence_msg[3][4] = {
	43	{0x05, 0x02, 0x51, 0x10},
	44	{0x05, 0x02, 0x52, 0x10},
	45	{0x07, 0x02, 0x01, 0x10}
	46	};
	47
	48	/* UUIDs for AMT F/W clients */
	49	const uuid_le mei_wd_guid = UUID_LE(0x05B79A6F, 0x4628, 0x4D7F, 0x89,
	50	0x9D, 0xA9, 0x15, 0x14, 0xCB,
	51	0x32, 0xAB);
	52
	53
55d33856	54	void mei_wd_set_start_timeout(struct mei_device *dev, u16 timeout)
3ceb3e66	55	{
55d33856	56	dev_dbg(&dev->pdev->dev, "timeout=%d.\n", timeout);
3ceb3e66 OW	57	memcpy(dev->wd_data, mei_start_wd_params, MEI_WD_PARAMS_SIZE);
3ceb3e66 OW	58	memcpy(dev->wd_data + MEI_WD_PARAMS_SIZE,
55d33856	59	&timeout, sizeof(u16));
3ceb3e66 OW	60	}
	61
	62	/**
	63	* host_init_wd - mei initialization wd.
	64	*
	65	* @dev: the device structure
	66	*/
617aa396	67	bool mei_wd_host_init(struct mei_device *dev)
3ceb3e66	68	{
617aa396 OW	69	bool ret = false;
617aa396 OW	70
c95efb74	71	mei_cl_init(&dev->wd_cl, dev);
3ceb3e66 OW	72
	73	/* look for WD client and connect to it */
	74	dev->wd_cl.state = MEI_FILE_DISCONNECTED;
	75	dev->wd_timeout = watchdog_timeout;
	76
	77	if (dev->wd_timeout > 0) {
3ceb3e66 OW	78	/* find ME WD client */
	79	mei_find_me_client_update_filext(dev, &dev->wd_cl,
	80	&mei_wd_guid, MEI_WD_HOST_CLIENT_ID);
	81
	82	dev_dbg(&dev->pdev->dev, "check wd_cl\n");
	83	if (MEI_FILE_CONNECTING == dev->wd_cl.state) {
	84	if (!mei_connect(dev, &dev->wd_cl)) {
	85	dev_dbg(&dev->pdev->dev, "Failed to connect to WD client\n");
	86	dev->wd_cl.state = MEI_FILE_DISCONNECTED;
	87	dev->wd_cl.host_client_id = 0;
617aa396 OW	88	ret = false;
617aa396 OW	89	goto end;
3ceb3e66 OW	90	} else {
	91	dev->wd_cl.timer_count = CONNECT_TIMEOUT;
	92	}
	93	} else {
	94	dev_dbg(&dev->pdev->dev, "Failed to find WD client\n");
617aa396 OW	95	ret = false;
617aa396 OW	96	goto end;
3ceb3e66 OW	97	}
	98	} else {
	99	dev->wd_bypass = true;
	100	dev_dbg(&dev->pdev->dev, "WD requested to be disabled\n");
617aa396 OW	101	ret = false;
617aa396 OW	102	goto end;
3ceb3e66	103	}
617aa396 OW	104
	105	end:
	106	return ret;
3ceb3e66 OW	107	}
	108
	109	/**
	110	* mei_wd_send - sends watch dog message to fw.
	111	*
	112	* @dev: the device structure
	113	*
	114	* returns 0 if success,
	115	* -EIO when message send fails
	116	* -EINVAL when invalid message is to be sent
	117	*/
	118	int mei_wd_send(struct mei_device *dev)
	119	{
	120	struct mei_msg_hdr *mei_hdr;
	121
	122	mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
	123	mei_hdr->host_addr = dev->wd_cl.host_client_id;
	124	mei_hdr->me_addr = dev->wd_cl.me_client_id;
	125	mei_hdr->msg_complete = 1;
	126	mei_hdr->reserved = 0;
	127
	128	if (!memcmp(dev->wd_data, mei_start_wd_params, MEI_WD_PARAMS_SIZE))
	129	mei_hdr->length = MEI_START_WD_DATA_SIZE;
	130	else if (!memcmp(dev->wd_data, mei_stop_wd_params, MEI_WD_PARAMS_SIZE))
	131	mei_hdr->length = MEI_WD_PARAMS_SIZE;
	132	else
	133	return -EINVAL;
	134
	135	if (mei_write_message(dev, mei_hdr, dev->wd_data, mei_hdr->length))
	136	return 0;
	137	return -EIO;
	138	}
	139
	140	int mei_wd_stop(struct mei_device *dev, bool preserve)
	141	{
	142	int ret;
	143	u16 wd_timeout = dev->wd_timeout;
	144
a61c6530	145	cancel_delayed_work(&dev->timer_work);
3ceb3e66 OW	146	if (dev->wd_cl.state != MEI_FILE_CONNECTED \|\| !dev->wd_timeout)
	147	return 0;
	148
	149	dev->wd_timeout = 0;
	150	dev->wd_due_counter = 0;
	151	memcpy(dev->wd_data, mei_stop_wd_params, MEI_WD_PARAMS_SIZE);
eb9af0ac	152	dev->stop = true;
3ceb3e66 OW	153
	154	ret = mei_flow_ctrl_creds(dev, &dev->wd_cl);
	155	if (ret < 0)
	156	goto out;
	157
	158	if (ret && dev->mei_host_buffer_is_empty) {
	159	ret = 0;
eb9af0ac	160	dev->mei_host_buffer_is_empty = false;
3ceb3e66 OW	161
	162	if (!mei_wd_send(dev)) {
	163	ret = mei_flow_ctrl_reduce(dev, &dev->wd_cl);
	164	if (ret)
	165	goto out;
	166	} else {
	167	dev_dbg(&dev->pdev->dev, "send stop WD failed\n");
	168	}
	169
eb9af0ac	170	dev->wd_pending = false;
3ceb3e66	171	} else {
eb9af0ac	172	dev->wd_pending = true;
3ceb3e66	173	}
eb9af0ac	174	dev->wd_stopped = false;
3ceb3e66 OW	175	mutex_unlock(&dev->device_lock);
	176
	177	ret = wait_event_interruptible_timeout(dev->wait_stop_wd,
	178	dev->wd_stopped, 10 * HZ);
	179	mutex_lock(&dev->device_lock);
a534bb6e TW	180	if (dev->wd_stopped) {
	181	dev_dbg(&dev->pdev->dev, "stop wd complete ret=%d.\n", ret);
	182	ret = 0;
	183	} else {
	184	if (!ret)
	185	ret = -ETIMEDOUT;
	186	dev_warn(&dev->pdev->dev,
	187	"stop wd failed to complete ret=%d.\n", ret);
	188	}
3ceb3e66 OW	189
	190	if (preserve)
	191	dev->wd_timeout = wd_timeout;
	192
	193	out:
	194	return ret;
	195	}
	196
4a3cafd5 OW	197	/*
	198	* mei_wd_ops_start - wd start command from the watchdog core.
	199	*
	200	* @wd_dev - watchdog device struct
	201	*
	202	* returns 0 if success, negative errno code for failure
	203	*/
	204	static int mei_wd_ops_start(struct watchdog_device *wd_dev)
	205	{
	206	int err = -ENODEV;
	207	struct mei_device *dev;
	208
	209	dev = pci_get_drvdata(mei_device);
	210	if (!dev)
	211	return -ENODEV;
	212
	213	mutex_lock(&dev->device_lock);
	214
	215	if (dev->mei_state != MEI_ENABLED) {
	216	dev_dbg(&dev->pdev->dev, "mei_state != MEI_ENABLED mei_state= %d\n",
	217	dev->mei_state);
	218	goto end_unlock;
	219	}
	220
	221	if (dev->wd_cl.state != MEI_FILE_CONNECTED) {
	222	dev_dbg(&dev->pdev->dev, "MEI Driver is not connected to Watchdog Client\n");
	223	goto end_unlock;
	224	}
	225
55d33856	226	mei_wd_set_start_timeout(dev, dev->wd_timeout);
4a3cafd5 OW	227
	228	err = 0;
	229	end_unlock:
	230	mutex_unlock(&dev->device_lock);
	231	return err;
	232	}
	233
	234	/*
	235	* mei_wd_ops_stop - wd stop command from the watchdog core.
	236	*
	237	* @wd_dev - watchdog device struct
	238	*
	239	* returns 0 if success, negative errno code for failure
	240	*/
	241	static int mei_wd_ops_stop(struct watchdog_device *wd_dev)
	242	{
	243	struct mei_device *dev;
	244	dev = pci_get_drvdata(mei_device);
	245
	246	if (!dev)
	247	return -ENODEV;
	248
	249	mutex_lock(&dev->device_lock);
	250	mei_wd_stop(dev, false);
	251	mutex_unlock(&dev->device_lock);
	252
	253	return 0;
	254	}
	255
8c4a59a7 OW	256	/*
	257	* mei_wd_ops_ping - wd ping command from the watchdog core.
	258	*
	259	* @wd_dev - watchdog device struct
	260	*
	261	* returns 0 if success, negative errno code for failure
	262	*/
	263	static int mei_wd_ops_ping(struct watchdog_device *wd_dev)
	264	{
	265	int ret = 0;
	266	struct mei_device *dev;
	267	dev = pci_get_drvdata(mei_device);
	268
	269	if (!dev)
	270	return -ENODEV;
	271
	272	mutex_lock(&dev->device_lock);
	273
	274	if (dev->wd_cl.state != MEI_FILE_CONNECTED) {
	275	dev_dbg(&dev->pdev->dev, "wd is not connected.\n");
	276	ret = -ENODEV;
	277	goto end;
	278	}
	279
	280	/* Check if we can send the ping to HW*/
	281	if (dev->mei_host_buffer_is_empty &&
	282	mei_flow_ctrl_creds(dev, &dev->wd_cl) > 0) {
	283
	284	dev->mei_host_buffer_is_empty = false;
	285	dev_dbg(&dev->pdev->dev, "sending watchdog ping\n");
	286
	287	if (mei_wd_send(dev)) {
	288	dev_dbg(&dev->pdev->dev, "wd send failed.\n");
	289	ret = -EIO;
	290	goto end;
	291	}
	292
	293	if (mei_flow_ctrl_reduce(dev, &dev->wd_cl)) {
	294	dev_dbg(&dev->pdev->dev, "mei_flow_ctrl_reduce() failed.\n");
	295	ret = -EIO;
	296	goto end;
	297	}
	298
	299	} else {
	300	dev->wd_pending = true;
	301	}
	302
	303	end:
	304	mutex_unlock(&dev->device_lock);
	305	return ret;
	306	}
	307
55d33856 OW	308	/*
	309	* mei_wd_ops_set_timeout - wd set timeout command from the watchdog core.
	310	*
	311	* @wd_dev - watchdog device struct
	312	* @timeout - timeout value to set
	313	*
	314	* returns 0 if success, negative errno code for failure
	315	*/
	316	static int mei_wd_ops_set_timeout(struct watchdog_device *wd_dev, unsigned int timeout)
	317	{
	318	struct mei_device *dev;
	319	dev = pci_get_drvdata(mei_device);
	320
	321	if (!dev)
	322	return -ENODEV;
	323
	324	/* Check Timeout value */
	325	if (timeout < AMT_WD_MIN_TIMEOUT \|\| timeout > AMT_WD_MAX_TIMEOUT)
	326	return -EINVAL;
	327
	328	mutex_lock(&dev->device_lock);
	329
	330	dev->wd_timeout = timeout;
	331	mei_wd_set_start_timeout(dev, dev->wd_timeout);
	332
	333	mutex_unlock(&dev->device_lock);
	334
	335	return 0;
	336	}
	337
4a3cafd5 OW	338	/*
	339	* Watchdog Device structs
	340	*/
	341	const struct watchdog_ops wd_ops = {
	342	.owner = THIS_MODULE,
	343	.start = mei_wd_ops_start,
	344	.stop = mei_wd_ops_stop,
8c4a59a7	345	.ping = mei_wd_ops_ping,
55d33856	346	.set_timeout = mei_wd_ops_set_timeout,
4a3cafd5 OW	347	};
	348	const struct watchdog_info wd_info = {
	349	.identity = INTEL_AMT_WATCHDOG_ID,
8c4a59a7	350	.options = WDIOF_KEEPALIVEPING,
4a3cafd5 OW	351	};
	352
	353	struct watchdog_device amt_wd_dev = {
	354	.info = &wd_info,
	355	.ops = &wd_ops,
	356	.timeout = AMT_WD_DEFAULT_TIMEOUT,
	357	.min_timeout = AMT_WD_MIN_TIMEOUT,
	358	.max_timeout = AMT_WD_MAX_TIMEOUT,
	359	};
	360
	361