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v6.8
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * drivers/char/watchdog/sp805-wdt.c
  4 *
  5 * Watchdog driver for ARM SP805 watchdog module
  6 *
  7 * Copyright (C) 2010 ST Microelectronics
  8 * Viresh Kumar <vireshk@kernel.org>
  9 *
 10 * This file is licensed under the terms of the GNU General Public
 11 * License version 2 or later. This program is licensed "as is" without any
 12 * warranty of any kind, whether express or implied.
 13 */
 14
 
 15#include <linux/device.h>
 16#include <linux/resource.h>
 17#include <linux/amba/bus.h>
 18#include <linux/bitops.h>
 19#include <linux/clk.h>
 20#include <linux/io.h>
 21#include <linux/ioport.h>
 22#include <linux/kernel.h>
 23#include <linux/math64.h>
 24#include <linux/module.h>
 25#include <linux/moduleparam.h>
 
 26#include <linux/pm.h>
 27#include <linux/property.h>
 28#include <linux/slab.h>
 29#include <linux/spinlock.h>
 30#include <linux/types.h>
 31#include <linux/watchdog.h>
 32
 33/* default timeout in seconds */
 34#define DEFAULT_TIMEOUT		60
 35
 36#define MODULE_NAME		"sp805-wdt"
 37
 38/* watchdog register offsets and masks */
 39#define WDTLOAD			0x000
 40	#define LOAD_MIN	0x00000001
 41	#define LOAD_MAX	0xFFFFFFFF
 42#define WDTVALUE		0x004
 43#define WDTCONTROL		0x008
 44	/* control register masks */
 45	#define	INT_ENABLE	(1 << 0)
 46	#define	RESET_ENABLE	(1 << 1)
 47	#define	ENABLE_MASK	(INT_ENABLE | RESET_ENABLE)
 48#define WDTINTCLR		0x00C
 49#define WDTRIS			0x010
 50#define WDTMIS			0x014
 51	#define INT_MASK	(1 << 0)
 52#define WDTLOCK			0xC00
 53	#define	UNLOCK		0x1ACCE551
 54	#define	LOCK		0x00000001
 55
 56/**
 57 * struct sp805_wdt: sp805 wdt device structure
 58 * @wdd: instance of struct watchdog_device
 59 * @lock: spin lock protecting dev structure and io access
 60 * @base: base address of wdt
 61 * @clk: (optional) clock structure of wdt
 62 * @rate: (optional) clock rate when provided via properties
 63 * @adev: amba device structure of wdt
 64 * @status: current status of wdt
 65 * @load_val: load value to be set for current timeout
 66 */
 67struct sp805_wdt {
 68	struct watchdog_device		wdd;
 69	spinlock_t			lock;
 70	void __iomem			*base;
 71	struct clk			*clk;
 72	u64				rate;
 73	struct amba_device		*adev;
 74	unsigned int			load_val;
 75};
 76
 77static bool nowayout = WATCHDOG_NOWAYOUT;
 78module_param(nowayout, bool, 0);
 79MODULE_PARM_DESC(nowayout,
 80		"Set to 1 to keep watchdog running after device release");
 81
 82/* returns true if wdt is running; otherwise returns false */
 83static bool wdt_is_running(struct watchdog_device *wdd)
 84{
 85	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
 86	u32 wdtcontrol = readl_relaxed(wdt->base + WDTCONTROL);
 87
 88	return (wdtcontrol & ENABLE_MASK) == ENABLE_MASK;
 89}
 90
 91/* This routine finds load value that will reset system in required timeout */
 92static int wdt_setload(struct watchdog_device *wdd, unsigned int timeout)
 93{
 94	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
 95	u64 load, rate;
 96
 97	rate = wdt->rate;
 98
 99	/*
100	 * sp805 runs counter with given value twice, after the end of first
101	 * counter it gives an interrupt and then starts counter again. If
102	 * interrupt already occurred then it resets the system. This is why
103	 * load is half of what should be required.
104	 */
105	load = div_u64(rate, 2) * timeout - 1;
106
107	load = (load > LOAD_MAX) ? LOAD_MAX : load;
108	load = (load < LOAD_MIN) ? LOAD_MIN : load;
109
110	spin_lock(&wdt->lock);
111	wdt->load_val = load;
112	/* roundup timeout to closest positive integer value */
113	wdd->timeout = div_u64((load + 1) * 2 + (rate / 2), rate);
114	spin_unlock(&wdt->lock);
115
116	return 0;
117}
118
119/* returns number of seconds left for reset to occur */
120static unsigned int wdt_timeleft(struct watchdog_device *wdd)
121{
122	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
123	u64 load;
124
125	spin_lock(&wdt->lock);
126	load = readl_relaxed(wdt->base + WDTVALUE);
127
128	/*If the interrupt is inactive then time left is WDTValue + WDTLoad. */
129	if (!(readl_relaxed(wdt->base + WDTRIS) & INT_MASK))
130		load += wdt->load_val + 1;
131	spin_unlock(&wdt->lock);
132
133	return div_u64(load, wdt->rate);
134}
135
136static int
137wdt_restart(struct watchdog_device *wdd, unsigned long mode, void *cmd)
138{
139	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
140
141	writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
142	writel_relaxed(0, wdt->base + WDTCONTROL);
143	writel_relaxed(0, wdt->base + WDTLOAD);
144	writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base + WDTCONTROL);
145
146	/* Flush posted writes. */
147	readl_relaxed(wdt->base + WDTLOCK);
148
149	return 0;
150}
151
152static int wdt_config(struct watchdog_device *wdd, bool ping)
153{
154	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
155	int ret;
156
157	if (!ping) {
158
159		ret = clk_prepare_enable(wdt->clk);
160		if (ret) {
161			dev_err(&wdt->adev->dev, "clock enable fail");
162			return ret;
163		}
164	}
165
166	spin_lock(&wdt->lock);
167
168	writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
169	writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
170	writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
171
172	if (!ping)
173		writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base +
174				WDTCONTROL);
175
176	writel_relaxed(LOCK, wdt->base + WDTLOCK);
177
178	/* Flush posted writes. */
179	readl_relaxed(wdt->base + WDTLOCK);
180	spin_unlock(&wdt->lock);
181
182	return 0;
183}
184
185static int wdt_ping(struct watchdog_device *wdd)
186{
187	return wdt_config(wdd, true);
188}
189
190/* enables watchdog timers reset */
191static int wdt_enable(struct watchdog_device *wdd)
192{
193	return wdt_config(wdd, false);
194}
195
196/* disables watchdog timers reset */
197static int wdt_disable(struct watchdog_device *wdd)
198{
199	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
200
201	spin_lock(&wdt->lock);
202
203	writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
204	writel_relaxed(0, wdt->base + WDTCONTROL);
205	writel_relaxed(LOCK, wdt->base + WDTLOCK);
206
207	/* Flush posted writes. */
208	readl_relaxed(wdt->base + WDTLOCK);
209	spin_unlock(&wdt->lock);
210
211	clk_disable_unprepare(wdt->clk);
212
213	return 0;
214}
215
216static const struct watchdog_info wdt_info = {
217	.options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
218	.identity = MODULE_NAME,
219};
220
221static const struct watchdog_ops wdt_ops = {
222	.owner		= THIS_MODULE,
223	.start		= wdt_enable,
224	.stop		= wdt_disable,
225	.ping		= wdt_ping,
226	.set_timeout	= wdt_setload,
227	.get_timeleft	= wdt_timeleft,
228	.restart	= wdt_restart,
229};
230
231static int
232sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id)
233{
234	struct sp805_wdt *wdt;
235	u64 rate = 0;
236	int ret = 0;
237
238	wdt = devm_kzalloc(&adev->dev, sizeof(*wdt), GFP_KERNEL);
239	if (!wdt) {
240		ret = -ENOMEM;
241		goto err;
242	}
243
244	wdt->base = devm_ioremap_resource(&adev->dev, &adev->res);
245	if (IS_ERR(wdt->base))
246		return PTR_ERR(wdt->base);
247
248	/*
249	 * When driver probe with ACPI device, clock devices
250	 * are not available, so watchdog rate get from
251	 * clock-frequency property given in _DSD object.
252	 */
253	device_property_read_u64(&adev->dev, "clock-frequency", &rate);
254
255	wdt->clk = devm_clk_get_optional(&adev->dev, NULL);
256	if (IS_ERR(wdt->clk))
257		return dev_err_probe(&adev->dev, PTR_ERR(wdt->clk), "Clock not found\n");
258
259	wdt->rate = clk_get_rate(wdt->clk);
260	if (!wdt->rate)
261		wdt->rate = rate;
262	if (!wdt->rate) {
263		dev_err(&adev->dev, "no clock-frequency property\n");
264		return -ENODEV;
 
 
265	}
266
267	wdt->adev = adev;
268	wdt->wdd.info = &wdt_info;
269	wdt->wdd.ops = &wdt_ops;
270	wdt->wdd.parent = &adev->dev;
271
272	spin_lock_init(&wdt->lock);
273	watchdog_set_nowayout(&wdt->wdd, nowayout);
274	watchdog_set_drvdata(&wdt->wdd, wdt);
275	watchdog_set_restart_priority(&wdt->wdd, 128);
276	watchdog_stop_on_unregister(&wdt->wdd);
277
278	/*
279	 * If 'timeout-sec' devicetree property is specified, use that.
280	 * Otherwise, use DEFAULT_TIMEOUT
281	 */
282	wdt->wdd.timeout = DEFAULT_TIMEOUT;
283	watchdog_init_timeout(&wdt->wdd, 0, &adev->dev);
284	wdt_setload(&wdt->wdd, wdt->wdd.timeout);
285
286	/*
287	 * If HW is already running, enable/reset the wdt and set the running
288	 * bit to tell the wdt subsystem
289	 */
290	if (wdt_is_running(&wdt->wdd)) {
291		wdt_enable(&wdt->wdd);
292		set_bit(WDOG_HW_RUNNING, &wdt->wdd.status);
293	}
294
295	watchdog_stop_on_reboot(&wdt->wdd);
296	ret = watchdog_register_device(&wdt->wdd);
297	if (ret)
298		goto err;
299	amba_set_drvdata(adev, wdt);
300
301	dev_info(&adev->dev, "registration successful\n");
302	return 0;
303
304err:
305	dev_err(&adev->dev, "Probe Failed!!!\n");
306	return ret;
307}
308
309static void sp805_wdt_remove(struct amba_device *adev)
310{
311	struct sp805_wdt *wdt = amba_get_drvdata(adev);
312
313	watchdog_unregister_device(&wdt->wdd);
314	watchdog_set_drvdata(&wdt->wdd, NULL);
 
 
315}
316
317static int __maybe_unused sp805_wdt_suspend(struct device *dev)
318{
319	struct sp805_wdt *wdt = dev_get_drvdata(dev);
320
321	if (watchdog_active(&wdt->wdd))
322		return wdt_disable(&wdt->wdd);
323
324	return 0;
325}
326
327static int __maybe_unused sp805_wdt_resume(struct device *dev)
328{
329	struct sp805_wdt *wdt = dev_get_drvdata(dev);
330
331	if (watchdog_active(&wdt->wdd))
332		return wdt_enable(&wdt->wdd);
333
334	return 0;
335}
336
337static SIMPLE_DEV_PM_OPS(sp805_wdt_dev_pm_ops, sp805_wdt_suspend,
338		sp805_wdt_resume);
339
340static const struct amba_id sp805_wdt_ids[] = {
341	{
342		.id	= 0x00141805,
343		.mask	= 0x00ffffff,
344	},
345	{
346		.id     = 0x001bb824,
347		.mask   = 0x00ffffff,
348	},
349	{ 0, 0 },
350};
351
352MODULE_DEVICE_TABLE(amba, sp805_wdt_ids);
353
354static struct amba_driver sp805_wdt_driver = {
355	.drv = {
356		.name	= MODULE_NAME,
357		.pm	= &sp805_wdt_dev_pm_ops,
358	},
359	.id_table	= sp805_wdt_ids,
360	.probe		= sp805_wdt_probe,
361	.remove = sp805_wdt_remove,
362};
363
364module_amba_driver(sp805_wdt_driver);
365
366MODULE_AUTHOR("Viresh Kumar <vireshk@kernel.org>");
367MODULE_DESCRIPTION("ARM SP805 Watchdog Driver");
368MODULE_LICENSE("GPL");
v5.4
 
  1/*
  2 * drivers/char/watchdog/sp805-wdt.c
  3 *
  4 * Watchdog driver for ARM SP805 watchdog module
  5 *
  6 * Copyright (C) 2010 ST Microelectronics
  7 * Viresh Kumar <vireshk@kernel.org>
  8 *
  9 * This file is licensed under the terms of the GNU General Public
 10 * License version 2 or later. This program is licensed "as is" without any
 11 * warranty of any kind, whether express or implied.
 12 */
 13
 14#include <linux/acpi.h>
 15#include <linux/device.h>
 16#include <linux/resource.h>
 17#include <linux/amba/bus.h>
 18#include <linux/bitops.h>
 19#include <linux/clk.h>
 20#include <linux/io.h>
 21#include <linux/ioport.h>
 22#include <linux/kernel.h>
 23#include <linux/math64.h>
 24#include <linux/module.h>
 25#include <linux/moduleparam.h>
 26#include <linux/of.h>
 27#include <linux/pm.h>
 
 28#include <linux/slab.h>
 29#include <linux/spinlock.h>
 30#include <linux/types.h>
 31#include <linux/watchdog.h>
 32
 33/* default timeout in seconds */
 34#define DEFAULT_TIMEOUT		60
 35
 36#define MODULE_NAME		"sp805-wdt"
 37
 38/* watchdog register offsets and masks */
 39#define WDTLOAD			0x000
 40	#define LOAD_MIN	0x00000001
 41	#define LOAD_MAX	0xFFFFFFFF
 42#define WDTVALUE		0x004
 43#define WDTCONTROL		0x008
 44	/* control register masks */
 45	#define	INT_ENABLE	(1 << 0)
 46	#define	RESET_ENABLE	(1 << 1)
 47	#define	ENABLE_MASK	(INT_ENABLE | RESET_ENABLE)
 48#define WDTINTCLR		0x00C
 49#define WDTRIS			0x010
 50#define WDTMIS			0x014
 51	#define INT_MASK	(1 << 0)
 52#define WDTLOCK			0xC00
 53	#define	UNLOCK		0x1ACCE551
 54	#define	LOCK		0x00000001
 55
 56/**
 57 * struct sp805_wdt: sp805 wdt device structure
 58 * @wdd: instance of struct watchdog_device
 59 * @lock: spin lock protecting dev structure and io access
 60 * @base: base address of wdt
 61 * @clk: clock structure of wdt
 
 62 * @adev: amba device structure of wdt
 63 * @status: current status of wdt
 64 * @load_val: load value to be set for current timeout
 65 */
 66struct sp805_wdt {
 67	struct watchdog_device		wdd;
 68	spinlock_t			lock;
 69	void __iomem			*base;
 70	struct clk			*clk;
 71	u64				rate;
 72	struct amba_device		*adev;
 73	unsigned int			load_val;
 74};
 75
 76static bool nowayout = WATCHDOG_NOWAYOUT;
 77module_param(nowayout, bool, 0);
 78MODULE_PARM_DESC(nowayout,
 79		"Set to 1 to keep watchdog running after device release");
 80
 81/* returns true if wdt is running; otherwise returns false */
 82static bool wdt_is_running(struct watchdog_device *wdd)
 83{
 84	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
 85	u32 wdtcontrol = readl_relaxed(wdt->base + WDTCONTROL);
 86
 87	return (wdtcontrol & ENABLE_MASK) == ENABLE_MASK;
 88}
 89
 90/* This routine finds load value that will reset system in required timout */
 91static int wdt_setload(struct watchdog_device *wdd, unsigned int timeout)
 92{
 93	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
 94	u64 load, rate;
 95
 96	rate = wdt->rate;
 97
 98	/*
 99	 * sp805 runs counter with given value twice, after the end of first
100	 * counter it gives an interrupt and then starts counter again. If
101	 * interrupt already occurred then it resets the system. This is why
102	 * load is half of what should be required.
103	 */
104	load = div_u64(rate, 2) * timeout - 1;
105
106	load = (load > LOAD_MAX) ? LOAD_MAX : load;
107	load = (load < LOAD_MIN) ? LOAD_MIN : load;
108
109	spin_lock(&wdt->lock);
110	wdt->load_val = load;
111	/* roundup timeout to closest positive integer value */
112	wdd->timeout = div_u64((load + 1) * 2 + (rate / 2), rate);
113	spin_unlock(&wdt->lock);
114
115	return 0;
116}
117
118/* returns number of seconds left for reset to occur */
119static unsigned int wdt_timeleft(struct watchdog_device *wdd)
120{
121	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
122	u64 load;
123
124	spin_lock(&wdt->lock);
125	load = readl_relaxed(wdt->base + WDTVALUE);
126
127	/*If the interrupt is inactive then time left is WDTValue + WDTLoad. */
128	if (!(readl_relaxed(wdt->base + WDTRIS) & INT_MASK))
129		load += wdt->load_val + 1;
130	spin_unlock(&wdt->lock);
131
132	return div_u64(load, wdt->rate);
133}
134
135static int
136wdt_restart(struct watchdog_device *wdd, unsigned long mode, void *cmd)
137{
138	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
139
 
140	writel_relaxed(0, wdt->base + WDTCONTROL);
141	writel_relaxed(0, wdt->base + WDTLOAD);
142	writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base + WDTCONTROL);
143
 
 
 
144	return 0;
145}
146
147static int wdt_config(struct watchdog_device *wdd, bool ping)
148{
149	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
150	int ret;
151
152	if (!ping) {
153
154		ret = clk_prepare_enable(wdt->clk);
155		if (ret) {
156			dev_err(&wdt->adev->dev, "clock enable fail");
157			return ret;
158		}
159	}
160
161	spin_lock(&wdt->lock);
162
163	writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
164	writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
165	writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
166
167	if (!ping)
168		writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base +
169				WDTCONTROL);
170
171	writel_relaxed(LOCK, wdt->base + WDTLOCK);
172
173	/* Flush posted writes. */
174	readl_relaxed(wdt->base + WDTLOCK);
175	spin_unlock(&wdt->lock);
176
177	return 0;
178}
179
180static int wdt_ping(struct watchdog_device *wdd)
181{
182	return wdt_config(wdd, true);
183}
184
185/* enables watchdog timers reset */
186static int wdt_enable(struct watchdog_device *wdd)
187{
188	return wdt_config(wdd, false);
189}
190
191/* disables watchdog timers reset */
192static int wdt_disable(struct watchdog_device *wdd)
193{
194	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
195
196	spin_lock(&wdt->lock);
197
198	writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
199	writel_relaxed(0, wdt->base + WDTCONTROL);
200	writel_relaxed(LOCK, wdt->base + WDTLOCK);
201
202	/* Flush posted writes. */
203	readl_relaxed(wdt->base + WDTLOCK);
204	spin_unlock(&wdt->lock);
205
206	clk_disable_unprepare(wdt->clk);
207
208	return 0;
209}
210
211static const struct watchdog_info wdt_info = {
212	.options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
213	.identity = MODULE_NAME,
214};
215
216static const struct watchdog_ops wdt_ops = {
217	.owner		= THIS_MODULE,
218	.start		= wdt_enable,
219	.stop		= wdt_disable,
220	.ping		= wdt_ping,
221	.set_timeout	= wdt_setload,
222	.get_timeleft	= wdt_timeleft,
223	.restart	= wdt_restart,
224};
225
226static int
227sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id)
228{
229	struct sp805_wdt *wdt;
 
230	int ret = 0;
231
232	wdt = devm_kzalloc(&adev->dev, sizeof(*wdt), GFP_KERNEL);
233	if (!wdt) {
234		ret = -ENOMEM;
235		goto err;
236	}
237
238	wdt->base = devm_ioremap_resource(&adev->dev, &adev->res);
239	if (IS_ERR(wdt->base))
240		return PTR_ERR(wdt->base);
241
242	if (adev->dev.of_node) {
243		wdt->clk = devm_clk_get(&adev->dev, NULL);
244		if (IS_ERR(wdt->clk)) {
245			dev_err(&adev->dev, "Clock not found\n");
246			return PTR_ERR(wdt->clk);
247		}
248		wdt->rate = clk_get_rate(wdt->clk);
249	} else if (has_acpi_companion(&adev->dev)) {
250		/*
251		 * When Driver probe with ACPI device, clock devices
252		 * are not available, so watchdog rate get from
253		 * clock-frequency property given in _DSD object.
254		 */
255		device_property_read_u64(&adev->dev, "clock-frequency",
256					 &wdt->rate);
257		if (!wdt->rate) {
258			dev_err(&adev->dev, "no clock-frequency property\n");
259			return -ENODEV;
260		}
261	}
262
263	wdt->adev = adev;
264	wdt->wdd.info = &wdt_info;
265	wdt->wdd.ops = &wdt_ops;
266	wdt->wdd.parent = &adev->dev;
267
268	spin_lock_init(&wdt->lock);
269	watchdog_set_nowayout(&wdt->wdd, nowayout);
270	watchdog_set_drvdata(&wdt->wdd, wdt);
271	watchdog_set_restart_priority(&wdt->wdd, 128);
 
272
273	/*
274	 * If 'timeout-sec' devicetree property is specified, use that.
275	 * Otherwise, use DEFAULT_TIMEOUT
276	 */
277	wdt->wdd.timeout = DEFAULT_TIMEOUT;
278	watchdog_init_timeout(&wdt->wdd, 0, &adev->dev);
279	wdt_setload(&wdt->wdd, wdt->wdd.timeout);
280
281	/*
282	 * If HW is already running, enable/reset the wdt and set the running
283	 * bit to tell the wdt subsystem
284	 */
285	if (wdt_is_running(&wdt->wdd)) {
286		wdt_enable(&wdt->wdd);
287		set_bit(WDOG_HW_RUNNING, &wdt->wdd.status);
288	}
289
 
290	ret = watchdog_register_device(&wdt->wdd);
291	if (ret)
292		goto err;
293	amba_set_drvdata(adev, wdt);
294
295	dev_info(&adev->dev, "registration successful\n");
296	return 0;
297
298err:
299	dev_err(&adev->dev, "Probe Failed!!!\n");
300	return ret;
301}
302
303static int sp805_wdt_remove(struct amba_device *adev)
304{
305	struct sp805_wdt *wdt = amba_get_drvdata(adev);
306
307	watchdog_unregister_device(&wdt->wdd);
308	watchdog_set_drvdata(&wdt->wdd, NULL);
309
310	return 0;
311}
312
313static int __maybe_unused sp805_wdt_suspend(struct device *dev)
314{
315	struct sp805_wdt *wdt = dev_get_drvdata(dev);
316
317	if (watchdog_active(&wdt->wdd))
318		return wdt_disable(&wdt->wdd);
319
320	return 0;
321}
322
323static int __maybe_unused sp805_wdt_resume(struct device *dev)
324{
325	struct sp805_wdt *wdt = dev_get_drvdata(dev);
326
327	if (watchdog_active(&wdt->wdd))
328		return wdt_enable(&wdt->wdd);
329
330	return 0;
331}
332
333static SIMPLE_DEV_PM_OPS(sp805_wdt_dev_pm_ops, sp805_wdt_suspend,
334		sp805_wdt_resume);
335
336static const struct amba_id sp805_wdt_ids[] = {
337	{
338		.id	= 0x00141805,
339		.mask	= 0x00ffffff,
 
 
 
 
340	},
341	{ 0, 0 },
342};
343
344MODULE_DEVICE_TABLE(amba, sp805_wdt_ids);
345
346static struct amba_driver sp805_wdt_driver = {
347	.drv = {
348		.name	= MODULE_NAME,
349		.pm	= &sp805_wdt_dev_pm_ops,
350	},
351	.id_table	= sp805_wdt_ids,
352	.probe		= sp805_wdt_probe,
353	.remove = sp805_wdt_remove,
354};
355
356module_amba_driver(sp805_wdt_driver);
357
358MODULE_AUTHOR("Viresh Kumar <vireshk@kernel.org>");
359MODULE_DESCRIPTION("ARM SP805 Watchdog Driver");
360MODULE_LICENSE("GPL");