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Linux 4.19.133
[linux/fpc-iii.git] / drivers / watchdog / s3c2410_wdt.c
blobadaa43543f0a7c2591ea0bf472926aa367567fa0
1 /*
2 * Copyright (c) 2004 Simtec Electronics
3 * Ben Dooks <ben@simtec.co.uk>
4 *
5 * S3C2410 Watchdog Timer Support
6 *
7 * Based on, softdog.c by Alan Cox,
8 * (c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 */
20
21 #include <linux/module.h>
22 #include <linux/moduleparam.h>
23 #include <linux/types.h>
24 #include <linux/timer.h>
25 #include <linux/watchdog.h>
26 #include <linux/platform_device.h>
27 #include <linux/interrupt.h>
28 #include <linux/clk.h>
29 #include <linux/uaccess.h>
30 #include <linux/io.h>
31 #include <linux/cpufreq.h>
32 #include <linux/slab.h>
33 #include <linux/err.h>
34 #include <linux/of.h>
35 #include <linux/of_device.h>
36 #include <linux/mfd/syscon.h>
37 #include <linux/regmap.h>
38 #include <linux/delay.h>
39
40 #define S3C2410_WTCON 0x00
41 #define S3C2410_WTDAT 0x04
42 #define S3C2410_WTCNT 0x08
43 #define S3C2410_WTCLRINT 0x0c
44
45 #define S3C2410_WTCNT_MAXCNT 0xffff
46
47 #define S3C2410_WTCON_RSTEN (1 << 0)
48 #define S3C2410_WTCON_INTEN (1 << 2)
49 #define S3C2410_WTCON_ENABLE (1 << 5)
50
51 #define S3C2410_WTCON_DIV16 (0 << 3)
52 #define S3C2410_WTCON_DIV32 (1 << 3)
53 #define S3C2410_WTCON_DIV64 (2 << 3)
54 #define S3C2410_WTCON_DIV128 (3 << 3)
55
56 #define S3C2410_WTCON_MAXDIV 0x80
57
58 #define S3C2410_WTCON_PRESCALE(x) ((x) << 8)
59 #define S3C2410_WTCON_PRESCALE_MASK (0xff << 8)
60 #define S3C2410_WTCON_PRESCALE_MAX 0xff
61
62 #define S3C2410_WATCHDOG_ATBOOT (0)
63 #define S3C2410_WATCHDOG_DEFAULT_TIME (15)
64
65 #define EXYNOS5_RST_STAT_REG_OFFSET 0x0404
66 #define EXYNOS5_WDT_DISABLE_REG_OFFSET 0x0408
67 #define EXYNOS5_WDT_MASK_RESET_REG_OFFSET 0x040c
68 #define QUIRK_HAS_PMU_CONFIG (1 << 0)
69 #define QUIRK_HAS_RST_STAT (1 << 1)
70 #define QUIRK_HAS_WTCLRINT_REG (1 << 2)
71
72 /* These quirks require that we have a PMU register map */
73 #define QUIRKS_HAVE_PMUREG (QUIRK_HAS_PMU_CONFIG | \
74 QUIRK_HAS_RST_STAT)
75
76 static bool nowayout = WATCHDOG_NOWAYOUT;
77 static int tmr_margin;
78 static int tmr_atboot = S3C2410_WATCHDOG_ATBOOT;
79 static int soft_noboot;
80
81 module_param(tmr_margin, int, 0);
82 module_param(tmr_atboot, int, 0);
83 module_param(nowayout, bool, 0);
84 module_param(soft_noboot, int, 0);
85
86 MODULE_PARM_DESC(tmr_margin, "Watchdog tmr_margin in seconds. (default="
87 __MODULE_STRING(S3C2410_WATCHDOG_DEFAULT_TIME) ")");
88 MODULE_PARM_DESC(tmr_atboot,
89 "Watchdog is started at boot time if set to 1, default="
90 __MODULE_STRING(S3C2410_WATCHDOG_ATBOOT));
91 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
92 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
93 MODULE_PARM_DESC(soft_noboot, "Watchdog action, set to 1 to ignore reboots, 0 to reboot (default 0)");
94
95 /**
96 * struct s3c2410_wdt_variant - Per-variant config data
97 *
98 * @disable_reg: Offset in pmureg for the register that disables the watchdog
99 * timer reset functionality.
100 * @mask_reset_reg: Offset in pmureg for the register that masks the watchdog
101 * timer reset functionality.
102 * @mask_bit: Bit number for the watchdog timer in the disable register and the
103 * mask reset register.
104 * @rst_stat_reg: Offset in pmureg for the register that has the reset status.
105 * @rst_stat_bit: Bit number in the rst_stat register indicating a watchdog
106 * reset.
107 * @quirks: A bitfield of quirks.
108 */
109
110 struct s3c2410_wdt_variant {
111 int disable_reg;
112 int mask_reset_reg;
113 int mask_bit;
114 int rst_stat_reg;
115 int rst_stat_bit;
116 u32 quirks;
117 };
118
119 struct s3c2410_wdt {
120 struct device *dev;
121 struct clk *clock;
122 void __iomem *reg_base;
123 unsigned int count;
124 spinlock_t lock;
125 unsigned long wtcon_save;
126 unsigned long wtdat_save;
127 struct watchdog_device wdt_device;
128 struct notifier_block freq_transition;
129 const struct s3c2410_wdt_variant *drv_data;
130 struct regmap *pmureg;
131 };
132
133 static const struct s3c2410_wdt_variant drv_data_s3c2410 = {
134 .quirks = 0
135 };
136
137 #ifdef CONFIG_OF
138 static const struct s3c2410_wdt_variant drv_data_s3c6410 = {
139 .quirks = QUIRK_HAS_WTCLRINT_REG,
140 };
141
142 static const struct s3c2410_wdt_variant drv_data_exynos5250 = {
143 .disable_reg = EXYNOS5_WDT_DISABLE_REG_OFFSET,
144 .mask_reset_reg = EXYNOS5_WDT_MASK_RESET_REG_OFFSET,
145 .mask_bit = 20,
146 .rst_stat_reg = EXYNOS5_RST_STAT_REG_OFFSET,
147 .rst_stat_bit = 20,
148 .quirks = QUIRK_HAS_PMU_CONFIG | QUIRK_HAS_RST_STAT \
149 | QUIRK_HAS_WTCLRINT_REG,
150 };
151
152 static const struct s3c2410_wdt_variant drv_data_exynos5420 = {
153 .disable_reg = EXYNOS5_WDT_DISABLE_REG_OFFSET,
154 .mask_reset_reg = EXYNOS5_WDT_MASK_RESET_REG_OFFSET,
155 .mask_bit = 0,
156 .rst_stat_reg = EXYNOS5_RST_STAT_REG_OFFSET,
157 .rst_stat_bit = 9,
158 .quirks = QUIRK_HAS_PMU_CONFIG | QUIRK_HAS_RST_STAT \
159 | QUIRK_HAS_WTCLRINT_REG,
160 };
161
162 static const struct s3c2410_wdt_variant drv_data_exynos7 = {
163 .disable_reg = EXYNOS5_WDT_DISABLE_REG_OFFSET,
164 .mask_reset_reg = EXYNOS5_WDT_MASK_RESET_REG_OFFSET,
165 .mask_bit = 23,
166 .rst_stat_reg = EXYNOS5_RST_STAT_REG_OFFSET,
167 .rst_stat_bit = 23, /* A57 WDTRESET */
168 .quirks = QUIRK_HAS_PMU_CONFIG | QUIRK_HAS_RST_STAT \
169 | QUIRK_HAS_WTCLRINT_REG,
170 };
171
172 static const struct of_device_id s3c2410_wdt_match[] = {
173 { .compatible = "samsung,s3c2410-wdt",
174 .data = &drv_data_s3c2410 },
175 { .compatible = "samsung,s3c6410-wdt",
176 .data = &drv_data_s3c6410 },
177 { .compatible = "samsung,exynos5250-wdt",
178 .data = &drv_data_exynos5250 },
179 { .compatible = "samsung,exynos5420-wdt",
180 .data = &drv_data_exynos5420 },
181 { .compatible = "samsung,exynos7-wdt",
182 .data = &drv_data_exynos7 },
183 {},
184 };
185 MODULE_DEVICE_TABLE(of, s3c2410_wdt_match);
186 #endif
187
188 static const struct platform_device_id s3c2410_wdt_ids[] = {
189 {
190 .name = "s3c2410-wdt",
191 .driver_data = (unsigned long)&drv_data_s3c2410,
192 },
193 {}
194 };
195 MODULE_DEVICE_TABLE(platform, s3c2410_wdt_ids);
196
197 /* functions */
198
199 static inline unsigned int s3c2410wdt_max_timeout(struct clk *clock)
200 {
201 unsigned long freq = clk_get_rate(clock);
202
203 return S3C2410_WTCNT_MAXCNT / (freq / (S3C2410_WTCON_PRESCALE_MAX + 1)
204 / S3C2410_WTCON_MAXDIV);
205 }
206
207 static inline struct s3c2410_wdt *freq_to_wdt(struct notifier_block *nb)
208 {
209 return container_of(nb, struct s3c2410_wdt, freq_transition);
210 }
211
212 static int s3c2410wdt_mask_and_disable_reset(struct s3c2410_wdt *wdt, bool mask)
213 {
214 int ret;
215 u32 mask_val = 1 << wdt->drv_data->mask_bit;
216 u32 val = 0;
217
218 /* No need to do anything if no PMU CONFIG needed */
219 if (!(wdt->drv_data->quirks & QUIRK_HAS_PMU_CONFIG))
220 return 0;
221
222 if (mask)
223 val = mask_val;
224
225 ret = regmap_update_bits(wdt->pmureg,
226 wdt->drv_data->disable_reg,
227 mask_val, val);
228 if (ret < 0)
229 goto error;
230
231 ret = regmap_update_bits(wdt->pmureg,
232 wdt->drv_data->mask_reset_reg,
233 mask_val, val);
234 error:
235 if (ret < 0)
236 dev_err(wdt->dev, "failed to update reg(%d)\n", ret);
237
238 return ret;
239 }
240
241 static int s3c2410wdt_keepalive(struct watchdog_device *wdd)
242 {
243 struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
244
245 spin_lock(&wdt->lock);
246 writel(wdt->count, wdt->reg_base + S3C2410_WTCNT);
247 spin_unlock(&wdt->lock);
248
249 return 0;
250 }
251
252 static void __s3c2410wdt_stop(struct s3c2410_wdt *wdt)
253 {
254 unsigned long wtcon;
255
256 wtcon = readl(wdt->reg_base + S3C2410_WTCON);
257 wtcon &= ~(S3C2410_WTCON_ENABLE | S3C2410_WTCON_RSTEN);
258 writel(wtcon, wdt->reg_base + S3C2410_WTCON);
259 }
260
261 static int s3c2410wdt_stop(struct watchdog_device *wdd)
262 {
263 struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
264
265 spin_lock(&wdt->lock);
266 __s3c2410wdt_stop(wdt);
267 spin_unlock(&wdt->lock);
268
269 return 0;
270 }
271
272 static int s3c2410wdt_start(struct watchdog_device *wdd)
273 {
274 unsigned long wtcon;
275 struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
276
277 spin_lock(&wdt->lock);
278
279 __s3c2410wdt_stop(wdt);
280
281 wtcon = readl(wdt->reg_base + S3C2410_WTCON);
282 wtcon |= S3C2410_WTCON_ENABLE | S3C2410_WTCON_DIV128;
283
284 if (soft_noboot) {
285 wtcon |= S3C2410_WTCON_INTEN;
286 wtcon &= ~S3C2410_WTCON_RSTEN;
287 } else {
288 wtcon &= ~S3C2410_WTCON_INTEN;
289 wtcon |= S3C2410_WTCON_RSTEN;
290 }
291
292 dev_dbg(wdt->dev, "Starting watchdog: count=0x%08x, wtcon=%08lx\n",
293 wdt->count, wtcon);
294
295 writel(wdt->count, wdt->reg_base + S3C2410_WTDAT);
296 writel(wdt->count, wdt->reg_base + S3C2410_WTCNT);
297 writel(wtcon, wdt->reg_base + S3C2410_WTCON);
298 spin_unlock(&wdt->lock);
299
300 return 0;
301 }
302
303 static inline int s3c2410wdt_is_running(struct s3c2410_wdt *wdt)
304 {
305 return readl(wdt->reg_base + S3C2410_WTCON) & S3C2410_WTCON_ENABLE;
306 }
307
308 static int s3c2410wdt_set_heartbeat(struct watchdog_device *wdd,
309 unsigned int timeout)
310 {
311 struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
312 unsigned long freq = clk_get_rate(wdt->clock);
313 unsigned int count;
314 unsigned int divisor = 1;
315 unsigned long wtcon;
316
317 if (timeout < 1)
318 return -EINVAL;
319
320 freq = DIV_ROUND_UP(freq, 128);
321 count = timeout * freq;
322
323 dev_dbg(wdt->dev, "Heartbeat: count=%d, timeout=%d, freq=%lu\n",
324 count, timeout, freq);
325
326 /* if the count is bigger than the watchdog register,
327 then work out what we need to do (and if) we can
328 actually make this value
329 */
330
331 if (count >= 0x10000) {
332 divisor = DIV_ROUND_UP(count, 0xffff);
333
334 if (divisor > 0x100) {
335 dev_err(wdt->dev, "timeout %d too big\n", timeout);
336 return -EINVAL;
337 }
338 }
339
340 dev_dbg(wdt->dev, "Heartbeat: timeout=%d, divisor=%d, count=%d (%08x)\n",
341 timeout, divisor, count, DIV_ROUND_UP(count, divisor));
342
343 count = DIV_ROUND_UP(count, divisor);
344 wdt->count = count;
345
346 /* update the pre-scaler */
347 wtcon = readl(wdt->reg_base + S3C2410_WTCON);
348 wtcon &= ~S3C2410_WTCON_PRESCALE_MASK;
349 wtcon |= S3C2410_WTCON_PRESCALE(divisor-1);
350
351 writel(count, wdt->reg_base + S3C2410_WTDAT);
352 writel(wtcon, wdt->reg_base + S3C2410_WTCON);
353
354 wdd->timeout = (count * divisor) / freq;
355
356 return 0;
357 }
358
359 static int s3c2410wdt_restart(struct watchdog_device *wdd, unsigned long action,
360 void *data)
361 {
362 struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
363 void __iomem *wdt_base = wdt->reg_base;
364
365 /* disable watchdog, to be safe */
366 writel(0, wdt_base + S3C2410_WTCON);
367
368 /* put initial values into count and data */
369 writel(0x80, wdt_base + S3C2410_WTCNT);
370 writel(0x80, wdt_base + S3C2410_WTDAT);
371
372 /* set the watchdog to go and reset... */
373 writel(S3C2410_WTCON_ENABLE | S3C2410_WTCON_DIV16 |
374 S3C2410_WTCON_RSTEN | S3C2410_WTCON_PRESCALE(0x20),
375 wdt_base + S3C2410_WTCON);
376
377 /* wait for reset to assert... */
378 mdelay(500);
379
380 return 0;
381 }
382
383 #define OPTIONS (WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE)
384
385 static const struct watchdog_info s3c2410_wdt_ident = {
386 .options = OPTIONS,
387 .firmware_version = 0,
388 .identity = "S3C2410 Watchdog",
389 };
390
391 static const struct watchdog_ops s3c2410wdt_ops = {
392 .owner = THIS_MODULE,
393 .start = s3c2410wdt_start,
394 .stop = s3c2410wdt_stop,
395 .ping = s3c2410wdt_keepalive,
396 .set_timeout = s3c2410wdt_set_heartbeat,
397 .restart = s3c2410wdt_restart,
398 };
399
400 static const struct watchdog_device s3c2410_wdd = {
401 .info = &s3c2410_wdt_ident,
402 .ops = &s3c2410wdt_ops,
403 .timeout = S3C2410_WATCHDOG_DEFAULT_TIME,
404 };
405
406 /* interrupt handler code */
407
408 static irqreturn_t s3c2410wdt_irq(int irqno, void *param)
409 {
410 struct s3c2410_wdt *wdt = platform_get_drvdata(param);
411
412 dev_info(wdt->dev, "watchdog timer expired (irq)\n");
413
414 s3c2410wdt_keepalive(&wdt->wdt_device);
415
416 if (wdt->drv_data->quirks & QUIRK_HAS_WTCLRINT_REG)
417 writel(0x1, wdt->reg_base + S3C2410_WTCLRINT);
418
419 return IRQ_HANDLED;
420 }
421
422 #ifdef CONFIG_ARM_S3C24XX_CPUFREQ
423
424 static int s3c2410wdt_cpufreq_transition(struct notifier_block *nb,
425 unsigned long val, void *data)
426 {
427 int ret;
428 struct s3c2410_wdt *wdt = freq_to_wdt(nb);
429
430 if (!s3c2410wdt_is_running(wdt))
431 goto done;
432
433 if (val == CPUFREQ_PRECHANGE) {
434 /* To ensure that over the change we don't cause the
435 * watchdog to trigger, we perform an keep-alive if
436 * the watchdog is running.
437 */
438
439 s3c2410wdt_keepalive(&wdt->wdt_device);
440 } else if (val == CPUFREQ_POSTCHANGE) {
441 s3c2410wdt_stop(&wdt->wdt_device);
442
443 ret = s3c2410wdt_set_heartbeat(&wdt->wdt_device,
444 wdt->wdt_device.timeout);
445
446 if (ret >= 0)
447 s3c2410wdt_start(&wdt->wdt_device);
448 else
449 goto err;
450 }
451
452 done:
453 return 0;
454
455 err:
456 dev_err(wdt->dev, "cannot set new value for timeout %d\n",
457 wdt->wdt_device.timeout);
458 return ret;
459 }
460
461 static inline int s3c2410wdt_cpufreq_register(struct s3c2410_wdt *wdt)
462 {
463 wdt->freq_transition.notifier_call = s3c2410wdt_cpufreq_transition;
464
465 return cpufreq_register_notifier(&wdt->freq_transition,
466 CPUFREQ_TRANSITION_NOTIFIER);
467 }
468
469 static inline void s3c2410wdt_cpufreq_deregister(struct s3c2410_wdt *wdt)
470 {
471 wdt->freq_transition.notifier_call = s3c2410wdt_cpufreq_transition;
472
473 cpufreq_unregister_notifier(&wdt->freq_transition,
474 CPUFREQ_TRANSITION_NOTIFIER);
475 }
476
477 #else
478
479 static inline int s3c2410wdt_cpufreq_register(struct s3c2410_wdt *wdt)
480 {
481 return 0;
482 }
483
484 static inline void s3c2410wdt_cpufreq_deregister(struct s3c2410_wdt *wdt)
485 {
486 }
487 #endif
488
489 static inline unsigned int s3c2410wdt_get_bootstatus(struct s3c2410_wdt *wdt)
490 {
491 unsigned int rst_stat;
492 int ret;
493
494 if (!(wdt->drv_data->quirks & QUIRK_HAS_RST_STAT))
495 return 0;
496
497 ret = regmap_read(wdt->pmureg, wdt->drv_data->rst_stat_reg, &rst_stat);
498 if (ret)
499 dev_warn(wdt->dev, "Couldn't get RST_STAT register\n");
500 else if (rst_stat & BIT(wdt->drv_data->rst_stat_bit))
501 return WDIOF_CARDRESET;
502
503 return 0;
504 }
505
506 static inline const struct s3c2410_wdt_variant *
507 s3c2410_get_wdt_drv_data(struct platform_device *pdev)
508 {
509 const struct s3c2410_wdt_variant *variant;
510
511 variant = of_device_get_match_data(&pdev->dev);
512 if (!variant) {
513 /* Device matched by platform_device_id */
514 variant = (struct s3c2410_wdt_variant *)
515 platform_get_device_id(pdev)->driver_data;
516 }
517
518 return variant;
519 }
520
521 static int s3c2410wdt_probe(struct platform_device *pdev)
522 {
523 struct device *dev = &pdev->dev;
524 struct s3c2410_wdt *wdt;
525 struct resource *wdt_mem;
526 struct resource *wdt_irq;
527 unsigned int wtcon;
528 int started = 0;
529 int ret;
530
531 wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
532 if (!wdt)
533 return -ENOMEM;
534
535 wdt->dev = dev;
536 spin_lock_init(&wdt->lock);
537 wdt->wdt_device = s3c2410_wdd;
538
539 wdt->drv_data = s3c2410_get_wdt_drv_data(pdev);
540 if (wdt->drv_data->quirks & QUIRKS_HAVE_PMUREG) {
541 wdt->pmureg = syscon_regmap_lookup_by_phandle(dev->of_node,
542 "samsung,syscon-phandle");
543 if (IS_ERR(wdt->pmureg)) {
544 dev_err(dev, "syscon regmap lookup failed.\n");
545 return PTR_ERR(wdt->pmureg);
546 }
547 }
548
549 wdt_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
550 if (wdt_irq == NULL) {
551 dev_err(dev, "no irq resource specified\n");
552 ret = -ENOENT;
553 goto err;
554 }
555
556 /* get the memory region for the watchdog timer */
557 wdt_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
558 wdt->reg_base = devm_ioremap_resource(dev, wdt_mem);
559 if (IS_ERR(wdt->reg_base)) {
560 ret = PTR_ERR(wdt->reg_base);
561 goto err;
562 }
563
564 wdt->clock = devm_clk_get(dev, "watchdog");
565 if (IS_ERR(wdt->clock)) {
566 dev_err(dev, "failed to find watchdog clock source\n");
567 ret = PTR_ERR(wdt->clock);
568 goto err;
569 }
570
571 ret = clk_prepare_enable(wdt->clock);
572 if (ret < 0) {
573 dev_err(dev, "failed to enable clock\n");
574 return ret;
575 }
576
577 wdt->wdt_device.min_timeout = 1;
578 wdt->wdt_device.max_timeout = s3c2410wdt_max_timeout(wdt->clock);
579
580 ret = s3c2410wdt_cpufreq_register(wdt);
581 if (ret < 0) {
582 dev_err(dev, "failed to register cpufreq\n");
583 goto err_clk;
584 }
585
586 watchdog_set_drvdata(&wdt->wdt_device, wdt);
587
588 /* see if we can actually set the requested timer margin, and if
589 * not, try the default value */
590
591 watchdog_init_timeout(&wdt->wdt_device, tmr_margin, dev);
592 ret = s3c2410wdt_set_heartbeat(&wdt->wdt_device,
593 wdt->wdt_device.timeout);
594 if (ret) {
595 started = s3c2410wdt_set_heartbeat(&wdt->wdt_device,
596 S3C2410_WATCHDOG_DEFAULT_TIME);
597
598 if (started == 0)
599 dev_info(dev,
600 "tmr_margin value out of range, default %d used\n",
601 S3C2410_WATCHDOG_DEFAULT_TIME);
602 else
603 dev_info(dev, "default timer value is out of range, cannot start\n");
604 }
605
606 ret = devm_request_irq(dev, wdt_irq->start, s3c2410wdt_irq, 0,
607 pdev->name, pdev);
608 if (ret != 0) {
609 dev_err(dev, "failed to install irq (%d)\n", ret);
610 goto err_cpufreq;
611 }
612
613 watchdog_set_nowayout(&wdt->wdt_device, nowayout);
614 watchdog_set_restart_priority(&wdt->wdt_device, 128);
615
616 wdt->wdt_device.bootstatus = s3c2410wdt_get_bootstatus(wdt);
617 wdt->wdt_device.parent = dev;
618
619 ret = watchdog_register_device(&wdt->wdt_device);
620 if (ret) {
621 dev_err(dev, "cannot register watchdog (%d)\n", ret);
622 goto err_cpufreq;
623 }
624
625 ret = s3c2410wdt_mask_and_disable_reset(wdt, false);
626 if (ret < 0)
627 goto err_unregister;
628
629 if (tmr_atboot && started == 0) {
630 dev_info(dev, "starting watchdog timer\n");
631 s3c2410wdt_start(&wdt->wdt_device);
632 } else if (!tmr_atboot) {
633 /* if we're not enabling the watchdog, then ensure it is
634 * disabled if it has been left running from the bootloader
635 * or other source */
636
637 s3c2410wdt_stop(&wdt->wdt_device);
638 }
639
640 platform_set_drvdata(pdev, wdt);
641
642 /* print out a statement of readiness */
643
644 wtcon = readl(wdt->reg_base + S3C2410_WTCON);
645
646 dev_info(dev, "watchdog %sactive, reset %sabled, irq %sabled\n",
647 (wtcon & S3C2410_WTCON_ENABLE) ? "" : "in",
648 (wtcon & S3C2410_WTCON_RSTEN) ? "en" : "dis",
649 (wtcon & S3C2410_WTCON_INTEN) ? "en" : "dis");
650
651 return 0;
652
653 err_unregister:
654 watchdog_unregister_device(&wdt->wdt_device);
655
656 err_cpufreq:
657 s3c2410wdt_cpufreq_deregister(wdt);
658
659 err_clk:
660 clk_disable_unprepare(wdt->clock);
661
662 err:
663 return ret;
664 }
665
666 static int s3c2410wdt_remove(struct platform_device *dev)
667 {
668 int ret;
669 struct s3c2410_wdt *wdt = platform_get_drvdata(dev);
670
671 ret = s3c2410wdt_mask_and_disable_reset(wdt, true);
672 if (ret < 0)
673 return ret;
674
675 watchdog_unregister_device(&wdt->wdt_device);
676
677 s3c2410wdt_cpufreq_deregister(wdt);
678
679 clk_disable_unprepare(wdt->clock);
680
681 return 0;
682 }
683
684 static void s3c2410wdt_shutdown(struct platform_device *dev)
685 {
686 struct s3c2410_wdt *wdt = platform_get_drvdata(dev);
687
688 s3c2410wdt_mask_and_disable_reset(wdt, true);
689
690 s3c2410wdt_stop(&wdt->wdt_device);
691 }
692
693 #ifdef CONFIG_PM_SLEEP
694
695 static int s3c2410wdt_suspend(struct device *dev)
696 {
697 int ret;
698 struct s3c2410_wdt *wdt = dev_get_drvdata(dev);
699
700 /* Save watchdog state, and turn it off. */
701 wdt->wtcon_save = readl(wdt->reg_base + S3C2410_WTCON);
702 wdt->wtdat_save = readl(wdt->reg_base + S3C2410_WTDAT);
703
704 ret = s3c2410wdt_mask_and_disable_reset(wdt, true);
705 if (ret < 0)
706 return ret;
707
708 /* Note that WTCNT doesn't need to be saved. */
709 s3c2410wdt_stop(&wdt->wdt_device);
710
711 return 0;
712 }
713
714 static int s3c2410wdt_resume(struct device *dev)
715 {
716 int ret;
717 struct s3c2410_wdt *wdt = dev_get_drvdata(dev);
718
719 /* Restore watchdog state. */
720 writel(wdt->wtdat_save, wdt->reg_base + S3C2410_WTDAT);
721 writel(wdt->wtdat_save, wdt->reg_base + S3C2410_WTCNT);/* Reset count */
722 writel(wdt->wtcon_save, wdt->reg_base + S3C2410_WTCON);
723
724 ret = s3c2410wdt_mask_and_disable_reset(wdt, false);
725 if (ret < 0)
726 return ret;
727
728 dev_info(dev, "watchdog %sabled\n",
729 (wdt->wtcon_save & S3C2410_WTCON_ENABLE) ? "en" : "dis");
730
731 return 0;
732 }
733 #endif
734
735 static SIMPLE_DEV_PM_OPS(s3c2410wdt_pm_ops, s3c2410wdt_suspend,
736 s3c2410wdt_resume);
737
738 static struct platform_driver s3c2410wdt_driver = {
739 .probe = s3c2410wdt_probe,
740 .remove = s3c2410wdt_remove,
741 .shutdown = s3c2410wdt_shutdown,
742 .id_table = s3c2410_wdt_ids,
743 .driver = {
744 .name = "s3c2410-wdt",
745 .pm = &s3c2410wdt_pm_ops,
746 .of_match_table = of_match_ptr(s3c2410_wdt_match),
747 },
748 };
749
750 module_platform_driver(s3c2410wdt_driver);
751
752 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>, Dimitry Andric <dimitry.andric@tomtom.com>");
753 MODULE_DESCRIPTION("S3C2410 Watchdog Device Driver");
754 MODULE_LICENSE("GPL");
Linux with added FPC-III support