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v6.2
  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");
v6.13.7
  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/reset.h>
 29#include <linux/slab.h>
 30#include <linux/spinlock.h>
 31#include <linux/types.h>
 32#include <linux/watchdog.h>
 33
 34/* default timeout in seconds */
 35#define DEFAULT_TIMEOUT		60
 36
 37#define MODULE_NAME		"sp805-wdt"
 38
 39/* watchdog register offsets and masks */
 40#define WDTLOAD			0x000
 41	#define LOAD_MIN	0x00000001
 42	#define LOAD_MAX	0xFFFFFFFF
 43#define WDTVALUE		0x004
 44#define WDTCONTROL		0x008
 45	/* control register masks */
 46	#define	INT_ENABLE	(1 << 0)
 47	#define	RESET_ENABLE	(1 << 1)
 48	#define	ENABLE_MASK	(INT_ENABLE | RESET_ENABLE)
 49#define WDTINTCLR		0x00C
 50#define WDTRIS			0x010
 51#define WDTMIS			0x014
 52	#define INT_MASK	(1 << 0)
 53#define WDTLOCK			0xC00
 54	#define	UNLOCK		0x1ACCE551
 55	#define	LOCK		0x00000001
 56
 57/**
 58 * struct sp805_wdt: sp805 wdt device structure
 59 * @wdd: instance of struct watchdog_device
 60 * @lock: spin lock protecting dev structure and io access
 61 * @base: base address of wdt
 62 * @clk: (optional) clock structure of wdt
 63 * @rate: (optional) clock rate when provided via properties
 64 * @adev: amba device structure of wdt
 65 * @status: current status of wdt
 66 * @load_val: load value to be set for current timeout
 67 */
 68struct sp805_wdt {
 69	struct watchdog_device		wdd;
 70	spinlock_t			lock;
 71	void __iomem			*base;
 72	struct clk			*clk;
 73	u64				rate;
 74	struct amba_device		*adev;
 75	unsigned int			load_val;
 76};
 77
 78static bool nowayout = WATCHDOG_NOWAYOUT;
 79module_param(nowayout, bool, 0);
 80MODULE_PARM_DESC(nowayout,
 81		"Set to 1 to keep watchdog running after device release");
 82
 83/* returns true if wdt is running; otherwise returns false */
 84static bool wdt_is_running(struct watchdog_device *wdd)
 85{
 86	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
 87	u32 wdtcontrol = readl_relaxed(wdt->base + WDTCONTROL);
 88
 89	return (wdtcontrol & ENABLE_MASK) == ENABLE_MASK;
 90}
 91
 92/* This routine finds load value that will reset system in required timeout */
 93static int wdt_setload(struct watchdog_device *wdd, unsigned int timeout)
 94{
 95	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
 96	u64 load, rate;
 97
 98	rate = wdt->rate;
 99
100	/*
101	 * sp805 runs counter with given value twice, after the end of first
102	 * counter it gives an interrupt and then starts counter again. If
103	 * interrupt already occurred then it resets the system. This is why
104	 * load is half of what should be required.
105	 */
106	load = div_u64(rate, 2) * timeout - 1;
107
108	load = (load > LOAD_MAX) ? LOAD_MAX : load;
109	load = (load < LOAD_MIN) ? LOAD_MIN : load;
110
111	spin_lock(&wdt->lock);
112	wdt->load_val = load;
113	/* roundup timeout to closest positive integer value */
114	wdd->timeout = div_u64((load + 1) * 2 + (rate / 2), rate);
115	spin_unlock(&wdt->lock);
116
117	return 0;
118}
119
120/* returns number of seconds left for reset to occur */
121static unsigned int wdt_timeleft(struct watchdog_device *wdd)
122{
123	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
124	u64 load;
125
126	spin_lock(&wdt->lock);
127	load = readl_relaxed(wdt->base + WDTVALUE);
128
129	/*If the interrupt is inactive then time left is WDTValue + WDTLoad. */
130	if (!(readl_relaxed(wdt->base + WDTRIS) & INT_MASK))
131		load += wdt->load_val + 1;
132	spin_unlock(&wdt->lock);
133
134	return div_u64(load, wdt->rate);
135}
136
137static int
138wdt_restart(struct watchdog_device *wdd, unsigned long mode, void *cmd)
139{
140	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
141
142	writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
143	writel_relaxed(0, wdt->base + WDTCONTROL);
144	writel_relaxed(0, wdt->base + WDTLOAD);
145	writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base + WDTCONTROL);
146
147	/* Flush posted writes. */
148	readl_relaxed(wdt->base + WDTLOCK);
149
150	return 0;
151}
152
153static int wdt_config(struct watchdog_device *wdd, bool ping)
154{
155	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
156	int ret;
157
158	if (!ping) {
159
160		ret = clk_prepare_enable(wdt->clk);
161		if (ret) {
162			dev_err(&wdt->adev->dev, "clock enable fail");
163			return ret;
164		}
165	}
166
167	spin_lock(&wdt->lock);
168
169	writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
170	writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
171	writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
172
173	if (!ping)
174		writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base +
175				WDTCONTROL);
176
177	writel_relaxed(LOCK, wdt->base + WDTLOCK);
178
179	/* Flush posted writes. */
180	readl_relaxed(wdt->base + WDTLOCK);
181	spin_unlock(&wdt->lock);
182
183	return 0;
184}
185
186static int wdt_ping(struct watchdog_device *wdd)
187{
188	return wdt_config(wdd, true);
189}
190
191/* enables watchdog timers reset */
192static int wdt_enable(struct watchdog_device *wdd)
193{
194	return wdt_config(wdd, false);
195}
196
197/* disables watchdog timers reset */
198static int wdt_disable(struct watchdog_device *wdd)
199{
200	struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
201
202	spin_lock(&wdt->lock);
203
204	writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
205	writel_relaxed(0, wdt->base + WDTCONTROL);
206	writel_relaxed(LOCK, wdt->base + WDTLOCK);
207
208	/* Flush posted writes. */
209	readl_relaxed(wdt->base + WDTLOCK);
210	spin_unlock(&wdt->lock);
211
212	clk_disable_unprepare(wdt->clk);
213
214	return 0;
215}
216
217static const struct watchdog_info wdt_info = {
218	.options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
219	.identity = MODULE_NAME,
220};
221
222static const struct watchdog_ops wdt_ops = {
223	.owner		= THIS_MODULE,
224	.start		= wdt_enable,
225	.stop		= wdt_disable,
226	.ping		= wdt_ping,
227	.set_timeout	= wdt_setload,
228	.get_timeleft	= wdt_timeleft,
229	.restart	= wdt_restart,
230};
231
232static int
233sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id)
234{
235	struct sp805_wdt *wdt;
236	struct reset_control *rst;
237	u64 rate = 0;
238	int ret = 0;
239
240	wdt = devm_kzalloc(&adev->dev, sizeof(*wdt), GFP_KERNEL);
241	if (!wdt) {
242		ret = -ENOMEM;
243		goto err;
244	}
245
246	wdt->base = devm_ioremap_resource(&adev->dev, &adev->res);
247	if (IS_ERR(wdt->base))
248		return PTR_ERR(wdt->base);
249
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", &rate);
256
257	wdt->clk = devm_clk_get_optional(&adev->dev, NULL);
258	if (IS_ERR(wdt->clk))
259		return dev_err_probe(&adev->dev, PTR_ERR(wdt->clk), "Clock not found\n");
260
261	wdt->rate = clk_get_rate(wdt->clk);
262	if (!wdt->rate)
263		wdt->rate = rate;
264	if (!wdt->rate) {
265		dev_err(&adev->dev, "no clock-frequency property\n");
266		return -ENODEV;
267	}
268
269	rst = devm_reset_control_get_optional_exclusive(&adev->dev, NULL);
270	if (IS_ERR(rst))
271		return dev_err_probe(&adev->dev, PTR_ERR(rst), "Can not get reset\n");
272
273	reset_control_deassert(rst);
274
275	wdt->adev = adev;
276	wdt->wdd.info = &wdt_info;
277	wdt->wdd.ops = &wdt_ops;
278	wdt->wdd.parent = &adev->dev;
279
280	spin_lock_init(&wdt->lock);
281	watchdog_set_nowayout(&wdt->wdd, nowayout);
282	watchdog_set_drvdata(&wdt->wdd, wdt);
283	watchdog_set_restart_priority(&wdt->wdd, 128);
284	watchdog_stop_on_unregister(&wdt->wdd);
285
286	/*
287	 * If 'timeout-sec' devicetree property is specified, use that.
288	 * Otherwise, use DEFAULT_TIMEOUT
289	 */
290	wdt->wdd.timeout = DEFAULT_TIMEOUT;
291	watchdog_init_timeout(&wdt->wdd, 0, &adev->dev);
292	wdt_setload(&wdt->wdd, wdt->wdd.timeout);
293
294	/*
295	 * If HW is already running, enable/reset the wdt and set the running
296	 * bit to tell the wdt subsystem
297	 */
298	if (wdt_is_running(&wdt->wdd)) {
299		wdt_enable(&wdt->wdd);
300		set_bit(WDOG_HW_RUNNING, &wdt->wdd.status);
301	}
302
303	watchdog_stop_on_reboot(&wdt->wdd);
304	ret = watchdog_register_device(&wdt->wdd);
305	if (ret)
306		goto err;
307	amba_set_drvdata(adev, wdt);
308
309	dev_info(&adev->dev, "registration successful\n");
310	return 0;
311
312err:
313	dev_err(&adev->dev, "Probe Failed!!!\n");
314	return ret;
315}
316
317static void sp805_wdt_remove(struct amba_device *adev)
318{
319	struct sp805_wdt *wdt = amba_get_drvdata(adev);
320
321	watchdog_unregister_device(&wdt->wdd);
322	watchdog_set_drvdata(&wdt->wdd, NULL);
323}
324
325static int __maybe_unused sp805_wdt_suspend(struct device *dev)
326{
327	struct sp805_wdt *wdt = dev_get_drvdata(dev);
328
329	if (watchdog_active(&wdt->wdd))
330		return wdt_disable(&wdt->wdd);
331
332	return 0;
333}
334
335static int __maybe_unused sp805_wdt_resume(struct device *dev)
336{
337	struct sp805_wdt *wdt = dev_get_drvdata(dev);
338
339	if (watchdog_active(&wdt->wdd))
340		return wdt_enable(&wdt->wdd);
341
342	return 0;
343}
344
345static SIMPLE_DEV_PM_OPS(sp805_wdt_dev_pm_ops, sp805_wdt_suspend,
346		sp805_wdt_resume);
347
348static const struct amba_id sp805_wdt_ids[] = {
349	{
350		.id	= 0x00141805,
351		.mask	= 0x00ffffff,
352	},
353	{
354		.id     = 0x001bb824,
355		.mask   = 0x00ffffff,
356	},
357	{ 0, 0 },
358};
359
360MODULE_DEVICE_TABLE(amba, sp805_wdt_ids);
361
362static struct amba_driver sp805_wdt_driver = {
363	.drv = {
364		.name	= MODULE_NAME,
365		.pm	= &sp805_wdt_dev_pm_ops,
366	},
367	.id_table	= sp805_wdt_ids,
368	.probe		= sp805_wdt_probe,
369	.remove = sp805_wdt_remove,
370};
371
372module_amba_driver(sp805_wdt_driver);
373
374MODULE_AUTHOR("Viresh Kumar <vireshk@kernel.org>");
375MODULE_DESCRIPTION("ARM SP805 Watchdog Driver");
376MODULE_LICENSE("GPL");