Merge tag 'linux-watchdog-5.4-rc1' of git://www.linux-watchdog.org/linux-watchdog
[linux-2.6-microblaze.git] / drivers / watchdog / orion_wdt.c
1 /*
2  * drivers/watchdog/orion_wdt.c
3  *
4  * Watchdog driver for Orion/Kirkwood processors
5  *
6  * Author: Sylver Bruneau <sylver.bruneau@googlemail.com>
7  *
8  * This file is licensed under  the terms of the GNU General Public
9  * License version 2. This program is licensed "as is" without any
10  * warranty of any kind, whether express or implied.
11  */
12
13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15 #include <linux/module.h>
16 #include <linux/moduleparam.h>
17 #include <linux/types.h>
18 #include <linux/kernel.h>
19 #include <linux/platform_device.h>
20 #include <linux/watchdog.h>
21 #include <linux/interrupt.h>
22 #include <linux/io.h>
23 #include <linux/clk.h>
24 #include <linux/err.h>
25 #include <linux/of.h>
26 #include <linux/of_device.h>
27
28 /* RSTOUT mask register physical address for Orion5x, Kirkwood and Dove */
29 #define ORION_RSTOUT_MASK_OFFSET        0x20108
30
31 /* Internal registers can be configured at any 1 MiB aligned address */
32 #define INTERNAL_REGS_MASK              ~(SZ_1M - 1)
33
34 /*
35  * Watchdog timer block registers.
36  */
37 #define TIMER_CTRL              0x0000
38 #define TIMER1_FIXED_ENABLE_BIT BIT(12)
39 #define WDT_AXP_FIXED_ENABLE_BIT BIT(10)
40 #define TIMER1_ENABLE_BIT       BIT(2)
41
42 #define TIMER_A370_STATUS       0x0004
43 #define WDT_A370_EXPIRED        BIT(31)
44 #define TIMER1_STATUS_BIT       BIT(8)
45
46 #define TIMER1_VAL_OFF          0x001c
47
48 #define WDT_MAX_CYCLE_COUNT     0xffffffff
49
50 #define WDT_A370_RATIO_MASK(v)  ((v) << 16)
51 #define WDT_A370_RATIO_SHIFT    5
52 #define WDT_A370_RATIO          (1 << WDT_A370_RATIO_SHIFT)
53
54 static bool nowayout = WATCHDOG_NOWAYOUT;
55 static int heartbeat = -1;              /* module parameter (seconds) */
56
57 struct orion_watchdog;
58
59 struct orion_watchdog_data {
60         int wdt_counter_offset;
61         int wdt_enable_bit;
62         int rstout_enable_bit;
63         int rstout_mask_bit;
64         int (*clock_init)(struct platform_device *,
65                           struct orion_watchdog *);
66         int (*enabled)(struct orion_watchdog *);
67         int (*start)(struct watchdog_device *);
68         int (*stop)(struct watchdog_device *);
69 };
70
71 struct orion_watchdog {
72         struct watchdog_device wdt;
73         void __iomem *reg;
74         void __iomem *rstout;
75         void __iomem *rstout_mask;
76         unsigned long clk_rate;
77         struct clk *clk;
78         const struct orion_watchdog_data *data;
79 };
80
81 static int orion_wdt_clock_init(struct platform_device *pdev,
82                                 struct orion_watchdog *dev)
83 {
84         int ret;
85
86         dev->clk = clk_get(&pdev->dev, NULL);
87         if (IS_ERR(dev->clk))
88                 return PTR_ERR(dev->clk);
89         ret = clk_prepare_enable(dev->clk);
90         if (ret) {
91                 clk_put(dev->clk);
92                 return ret;
93         }
94
95         dev->clk_rate = clk_get_rate(dev->clk);
96         return 0;
97 }
98
99 static int armada370_wdt_clock_init(struct platform_device *pdev,
100                                     struct orion_watchdog *dev)
101 {
102         int ret;
103
104         dev->clk = clk_get(&pdev->dev, NULL);
105         if (IS_ERR(dev->clk))
106                 return PTR_ERR(dev->clk);
107         ret = clk_prepare_enable(dev->clk);
108         if (ret) {
109                 clk_put(dev->clk);
110                 return ret;
111         }
112
113         /* Setup watchdog input clock */
114         atomic_io_modify(dev->reg + TIMER_CTRL,
115                         WDT_A370_RATIO_MASK(WDT_A370_RATIO_SHIFT),
116                         WDT_A370_RATIO_MASK(WDT_A370_RATIO_SHIFT));
117
118         dev->clk_rate = clk_get_rate(dev->clk) / WDT_A370_RATIO;
119         return 0;
120 }
121
122 static int armada375_wdt_clock_init(struct platform_device *pdev,
123                                     struct orion_watchdog *dev)
124 {
125         int ret;
126
127         dev->clk = of_clk_get_by_name(pdev->dev.of_node, "fixed");
128         if (!IS_ERR(dev->clk)) {
129                 ret = clk_prepare_enable(dev->clk);
130                 if (ret) {
131                         clk_put(dev->clk);
132                         return ret;
133                 }
134
135                 atomic_io_modify(dev->reg + TIMER_CTRL,
136                                 WDT_AXP_FIXED_ENABLE_BIT,
137                                 WDT_AXP_FIXED_ENABLE_BIT);
138                 dev->clk_rate = clk_get_rate(dev->clk);
139
140                 return 0;
141         }
142
143         /* Mandatory fallback for proper devicetree backward compatibility */
144         dev->clk = clk_get(&pdev->dev, NULL);
145         if (IS_ERR(dev->clk))
146                 return PTR_ERR(dev->clk);
147
148         ret = clk_prepare_enable(dev->clk);
149         if (ret) {
150                 clk_put(dev->clk);
151                 return ret;
152         }
153
154         atomic_io_modify(dev->reg + TIMER_CTRL,
155                         WDT_A370_RATIO_MASK(WDT_A370_RATIO_SHIFT),
156                         WDT_A370_RATIO_MASK(WDT_A370_RATIO_SHIFT));
157         dev->clk_rate = clk_get_rate(dev->clk) / WDT_A370_RATIO;
158
159         return 0;
160 }
161
162 static int armadaxp_wdt_clock_init(struct platform_device *pdev,
163                                    struct orion_watchdog *dev)
164 {
165         int ret;
166         u32 val;
167
168         dev->clk = of_clk_get_by_name(pdev->dev.of_node, "fixed");
169         if (IS_ERR(dev->clk))
170                 return PTR_ERR(dev->clk);
171         ret = clk_prepare_enable(dev->clk);
172         if (ret) {
173                 clk_put(dev->clk);
174                 return ret;
175         }
176
177         /* Fix the wdt and timer1 clock freqency to 25MHz */
178         val = WDT_AXP_FIXED_ENABLE_BIT | TIMER1_FIXED_ENABLE_BIT;
179         atomic_io_modify(dev->reg + TIMER_CTRL, val, val);
180
181         dev->clk_rate = clk_get_rate(dev->clk);
182         return 0;
183 }
184
185 static int orion_wdt_ping(struct watchdog_device *wdt_dev)
186 {
187         struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
188         /* Reload watchdog duration */
189         writel(dev->clk_rate * wdt_dev->timeout,
190                dev->reg + dev->data->wdt_counter_offset);
191         if (dev->wdt.info->options & WDIOF_PRETIMEOUT)
192                 writel(dev->clk_rate * (wdt_dev->timeout - wdt_dev->pretimeout),
193                        dev->reg + TIMER1_VAL_OFF);
194
195         return 0;
196 }
197
198 static int armada375_start(struct watchdog_device *wdt_dev)
199 {
200         struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
201         u32 reg;
202
203         /* Set watchdog duration */
204         writel(dev->clk_rate * wdt_dev->timeout,
205                dev->reg + dev->data->wdt_counter_offset);
206         if (dev->wdt.info->options & WDIOF_PRETIMEOUT)
207                 writel(dev->clk_rate * (wdt_dev->timeout - wdt_dev->pretimeout),
208                        dev->reg + TIMER1_VAL_OFF);
209
210         /* Clear the watchdog expiration bit */
211         atomic_io_modify(dev->reg + TIMER_A370_STATUS, WDT_A370_EXPIRED, 0);
212
213         /* Enable watchdog timer */
214         reg = dev->data->wdt_enable_bit;
215         if (dev->wdt.info->options & WDIOF_PRETIMEOUT)
216                 reg |= TIMER1_ENABLE_BIT;
217         atomic_io_modify(dev->reg + TIMER_CTRL, reg, reg);
218
219         /* Enable reset on watchdog */
220         reg = readl(dev->rstout);
221         reg |= dev->data->rstout_enable_bit;
222         writel(reg, dev->rstout);
223
224         atomic_io_modify(dev->rstout_mask, dev->data->rstout_mask_bit, 0);
225         return 0;
226 }
227
228 static int armada370_start(struct watchdog_device *wdt_dev)
229 {
230         struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
231         u32 reg;
232
233         /* Set watchdog duration */
234         writel(dev->clk_rate * wdt_dev->timeout,
235                dev->reg + dev->data->wdt_counter_offset);
236
237         /* Clear the watchdog expiration bit */
238         atomic_io_modify(dev->reg + TIMER_A370_STATUS, WDT_A370_EXPIRED, 0);
239
240         /* Enable watchdog timer */
241         atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit,
242                                                 dev->data->wdt_enable_bit);
243
244         /* Enable reset on watchdog */
245         reg = readl(dev->rstout);
246         reg |= dev->data->rstout_enable_bit;
247         writel(reg, dev->rstout);
248         return 0;
249 }
250
251 static int orion_start(struct watchdog_device *wdt_dev)
252 {
253         struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
254
255         /* Set watchdog duration */
256         writel(dev->clk_rate * wdt_dev->timeout,
257                dev->reg + dev->data->wdt_counter_offset);
258
259         /* Enable watchdog timer */
260         atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit,
261                                                 dev->data->wdt_enable_bit);
262
263         /* Enable reset on watchdog */
264         atomic_io_modify(dev->rstout, dev->data->rstout_enable_bit,
265                                       dev->data->rstout_enable_bit);
266
267         return 0;
268 }
269
270 static int orion_wdt_start(struct watchdog_device *wdt_dev)
271 {
272         struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
273
274         /* There are some per-SoC quirks to handle */
275         return dev->data->start(wdt_dev);
276 }
277
278 static int orion_stop(struct watchdog_device *wdt_dev)
279 {
280         struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
281
282         /* Disable reset on watchdog */
283         atomic_io_modify(dev->rstout, dev->data->rstout_enable_bit, 0);
284
285         /* Disable watchdog timer */
286         atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit, 0);
287
288         return 0;
289 }
290
291 static int armada375_stop(struct watchdog_device *wdt_dev)
292 {
293         struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
294         u32 reg, mask;
295
296         /* Disable reset on watchdog */
297         atomic_io_modify(dev->rstout_mask, dev->data->rstout_mask_bit,
298                                            dev->data->rstout_mask_bit);
299         reg = readl(dev->rstout);
300         reg &= ~dev->data->rstout_enable_bit;
301         writel(reg, dev->rstout);
302
303         /* Disable watchdog timer */
304         mask = dev->data->wdt_enable_bit;
305         if (wdt_dev->info->options & WDIOF_PRETIMEOUT)
306                 mask |= TIMER1_ENABLE_BIT;
307         atomic_io_modify(dev->reg + TIMER_CTRL, mask, 0);
308
309         return 0;
310 }
311
312 static int armada370_stop(struct watchdog_device *wdt_dev)
313 {
314         struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
315         u32 reg;
316
317         /* Disable reset on watchdog */
318         reg = readl(dev->rstout);
319         reg &= ~dev->data->rstout_enable_bit;
320         writel(reg, dev->rstout);
321
322         /* Disable watchdog timer */
323         atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit, 0);
324
325         return 0;
326 }
327
328 static int orion_wdt_stop(struct watchdog_device *wdt_dev)
329 {
330         struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
331
332         return dev->data->stop(wdt_dev);
333 }
334
335 static int orion_enabled(struct orion_watchdog *dev)
336 {
337         bool enabled, running;
338
339         enabled = readl(dev->rstout) & dev->data->rstout_enable_bit;
340         running = readl(dev->reg + TIMER_CTRL) & dev->data->wdt_enable_bit;
341
342         return enabled && running;
343 }
344
345 static int armada375_enabled(struct orion_watchdog *dev)
346 {
347         bool masked, enabled, running;
348
349         masked = readl(dev->rstout_mask) & dev->data->rstout_mask_bit;
350         enabled = readl(dev->rstout) & dev->data->rstout_enable_bit;
351         running = readl(dev->reg + TIMER_CTRL) & dev->data->wdt_enable_bit;
352
353         return !masked && enabled && running;
354 }
355
356 static int orion_wdt_enabled(struct watchdog_device *wdt_dev)
357 {
358         struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
359
360         return dev->data->enabled(dev);
361 }
362
363 static unsigned int orion_wdt_get_timeleft(struct watchdog_device *wdt_dev)
364 {
365         struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
366         return readl(dev->reg + dev->data->wdt_counter_offset) / dev->clk_rate;
367 }
368
369 static struct watchdog_info orion_wdt_info = {
370         .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
371         .identity = "Orion Watchdog",
372 };
373
374 static const struct watchdog_ops orion_wdt_ops = {
375         .owner = THIS_MODULE,
376         .start = orion_wdt_start,
377         .stop = orion_wdt_stop,
378         .ping = orion_wdt_ping,
379         .get_timeleft = orion_wdt_get_timeleft,
380 };
381
382 static irqreturn_t orion_wdt_irq(int irq, void *devid)
383 {
384         panic("Watchdog Timeout");
385         return IRQ_HANDLED;
386 }
387
388 static irqreturn_t orion_wdt_pre_irq(int irq, void *devid)
389 {
390         struct orion_watchdog *dev = devid;
391
392         atomic_io_modify(dev->reg + TIMER_A370_STATUS,
393                          TIMER1_STATUS_BIT, 0);
394         watchdog_notify_pretimeout(&dev->wdt);
395         return IRQ_HANDLED;
396 }
397
398 /*
399  * The original devicetree binding for this driver specified only
400  * one memory resource, so in order to keep DT backwards compatibility
401  * we try to fallback to a hardcoded register address, if the resource
402  * is missing from the devicetree.
403  */
404 static void __iomem *orion_wdt_ioremap_rstout(struct platform_device *pdev,
405                                               phys_addr_t internal_regs)
406 {
407         struct resource *res;
408         phys_addr_t rstout;
409
410         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
411         if (res)
412                 return devm_ioremap(&pdev->dev, res->start,
413                                     resource_size(res));
414
415         rstout = internal_regs + ORION_RSTOUT_MASK_OFFSET;
416
417         WARN(1, FW_BUG "falling back to hardcoded RSTOUT reg %pa\n", &rstout);
418         return devm_ioremap(&pdev->dev, rstout, 0x4);
419 }
420
421 static const struct orion_watchdog_data orion_data = {
422         .rstout_enable_bit = BIT(1),
423         .wdt_enable_bit = BIT(4),
424         .wdt_counter_offset = 0x24,
425         .clock_init = orion_wdt_clock_init,
426         .enabled = orion_enabled,
427         .start = orion_start,
428         .stop = orion_stop,
429 };
430
431 static const struct orion_watchdog_data armada370_data = {
432         .rstout_enable_bit = BIT(8),
433         .wdt_enable_bit = BIT(8),
434         .wdt_counter_offset = 0x34,
435         .clock_init = armada370_wdt_clock_init,
436         .enabled = orion_enabled,
437         .start = armada370_start,
438         .stop = armada370_stop,
439 };
440
441 static const struct orion_watchdog_data armadaxp_data = {
442         .rstout_enable_bit = BIT(8),
443         .wdt_enable_bit = BIT(8),
444         .wdt_counter_offset = 0x34,
445         .clock_init = armadaxp_wdt_clock_init,
446         .enabled = orion_enabled,
447         .start = armada370_start,
448         .stop = armada370_stop,
449 };
450
451 static const struct orion_watchdog_data armada375_data = {
452         .rstout_enable_bit = BIT(8),
453         .rstout_mask_bit = BIT(10),
454         .wdt_enable_bit = BIT(8),
455         .wdt_counter_offset = 0x34,
456         .clock_init = armada375_wdt_clock_init,
457         .enabled = armada375_enabled,
458         .start = armada375_start,
459         .stop = armada375_stop,
460 };
461
462 static const struct orion_watchdog_data armada380_data = {
463         .rstout_enable_bit = BIT(8),
464         .rstout_mask_bit = BIT(10),
465         .wdt_enable_bit = BIT(8),
466         .wdt_counter_offset = 0x34,
467         .clock_init = armadaxp_wdt_clock_init,
468         .enabled = armada375_enabled,
469         .start = armada375_start,
470         .stop = armada375_stop,
471 };
472
473 static const struct of_device_id orion_wdt_of_match_table[] = {
474         {
475                 .compatible = "marvell,orion-wdt",
476                 .data = &orion_data,
477         },
478         {
479                 .compatible = "marvell,armada-370-wdt",
480                 .data = &armada370_data,
481         },
482         {
483                 .compatible = "marvell,armada-xp-wdt",
484                 .data = &armadaxp_data,
485         },
486         {
487                 .compatible = "marvell,armada-375-wdt",
488                 .data = &armada375_data,
489         },
490         {
491                 .compatible = "marvell,armada-380-wdt",
492                 .data = &armada380_data,
493         },
494         {},
495 };
496 MODULE_DEVICE_TABLE(of, orion_wdt_of_match_table);
497
498 static int orion_wdt_get_regs(struct platform_device *pdev,
499                               struct orion_watchdog *dev)
500 {
501         struct device_node *node = pdev->dev.of_node;
502         struct resource *res;
503
504         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
505         if (!res)
506                 return -ENODEV;
507         dev->reg = devm_ioremap(&pdev->dev, res->start,
508                                 resource_size(res));
509         if (!dev->reg)
510                 return -ENOMEM;
511
512         /* Each supported compatible has some RSTOUT register quirk */
513         if (of_device_is_compatible(node, "marvell,orion-wdt")) {
514
515                 dev->rstout = orion_wdt_ioremap_rstout(pdev, res->start &
516                                                        INTERNAL_REGS_MASK);
517                 if (!dev->rstout)
518                         return -ENODEV;
519
520         } else if (of_device_is_compatible(node, "marvell,armada-370-wdt") ||
521                    of_device_is_compatible(node, "marvell,armada-xp-wdt")) {
522
523                 /* Dedicated RSTOUT register, can be requested. */
524                 dev->rstout = devm_platform_ioremap_resource(pdev, 1);
525                 if (IS_ERR(dev->rstout))
526                         return PTR_ERR(dev->rstout);
527
528         } else if (of_device_is_compatible(node, "marvell,armada-375-wdt") ||
529                    of_device_is_compatible(node, "marvell,armada-380-wdt")) {
530
531                 /* Dedicated RSTOUT register, can be requested. */
532                 dev->rstout = devm_platform_ioremap_resource(pdev, 1);
533                 if (IS_ERR(dev->rstout))
534                         return PTR_ERR(dev->rstout);
535
536                 res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
537                 if (!res)
538                         return -ENODEV;
539                 dev->rstout_mask = devm_ioremap(&pdev->dev, res->start,
540                                                 resource_size(res));
541                 if (!dev->rstout_mask)
542                         return -ENOMEM;
543
544         } else {
545                 return -ENODEV;
546         }
547
548         return 0;
549 }
550
551 static int orion_wdt_probe(struct platform_device *pdev)
552 {
553         struct orion_watchdog *dev;
554         const struct of_device_id *match;
555         unsigned int wdt_max_duration;  /* (seconds) */
556         int ret, irq;
557
558         dev = devm_kzalloc(&pdev->dev, sizeof(struct orion_watchdog),
559                            GFP_KERNEL);
560         if (!dev)
561                 return -ENOMEM;
562
563         match = of_match_device(orion_wdt_of_match_table, &pdev->dev);
564         if (!match)
565                 /* Default legacy match */
566                 match = &orion_wdt_of_match_table[0];
567
568         dev->wdt.info = &orion_wdt_info;
569         dev->wdt.ops = &orion_wdt_ops;
570         dev->wdt.min_timeout = 1;
571         dev->data = match->data;
572
573         ret = orion_wdt_get_regs(pdev, dev);
574         if (ret)
575                 return ret;
576
577         ret = dev->data->clock_init(pdev, dev);
578         if (ret) {
579                 dev_err(&pdev->dev, "cannot initialize clock\n");
580                 return ret;
581         }
582
583         wdt_max_duration = WDT_MAX_CYCLE_COUNT / dev->clk_rate;
584
585         dev->wdt.timeout = wdt_max_duration;
586         dev->wdt.max_timeout = wdt_max_duration;
587         dev->wdt.parent = &pdev->dev;
588         watchdog_init_timeout(&dev->wdt, heartbeat, &pdev->dev);
589
590         platform_set_drvdata(pdev, &dev->wdt);
591         watchdog_set_drvdata(&dev->wdt, dev);
592
593         /*
594          * Let's make sure the watchdog is fully stopped, unless it's
595          * explicitly enabled. This may be the case if the module was
596          * removed and re-inserted, or if the bootloader explicitly
597          * set a running watchdog before booting the kernel.
598          */
599         if (!orion_wdt_enabled(&dev->wdt))
600                 orion_wdt_stop(&dev->wdt);
601         else
602                 set_bit(WDOG_HW_RUNNING, &dev->wdt.status);
603
604         /* Request the IRQ only after the watchdog is disabled */
605         irq = platform_get_irq(pdev, 0);
606         if (irq > 0) {
607                 /*
608                  * Not all supported platforms specify an interrupt for the
609                  * watchdog, so let's make it optional.
610                  */
611                 ret = devm_request_irq(&pdev->dev, irq, orion_wdt_irq, 0,
612                                        pdev->name, dev);
613                 if (ret < 0) {
614                         dev_err(&pdev->dev, "failed to request IRQ\n");
615                         goto disable_clk;
616                 }
617         }
618
619         /* Optional 2nd interrupt for pretimeout */
620         irq = platform_get_irq(pdev, 1);
621         if (irq > 0) {
622                 orion_wdt_info.options |= WDIOF_PRETIMEOUT;
623                 ret = devm_request_irq(&pdev->dev, irq, orion_wdt_pre_irq,
624                                        0, pdev->name, dev);
625                 if (ret < 0) {
626                         dev_err(&pdev->dev, "failed to request IRQ\n");
627                         goto disable_clk;
628                 }
629         }
630
631
632         watchdog_set_nowayout(&dev->wdt, nowayout);
633         ret = watchdog_register_device(&dev->wdt);
634         if (ret)
635                 goto disable_clk;
636
637         pr_info("Initial timeout %d sec%s\n",
638                 dev->wdt.timeout, nowayout ? ", nowayout" : "");
639         return 0;
640
641 disable_clk:
642         clk_disable_unprepare(dev->clk);
643         clk_put(dev->clk);
644         return ret;
645 }
646
647 static int orion_wdt_remove(struct platform_device *pdev)
648 {
649         struct watchdog_device *wdt_dev = platform_get_drvdata(pdev);
650         struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
651
652         watchdog_unregister_device(wdt_dev);
653         clk_disable_unprepare(dev->clk);
654         clk_put(dev->clk);
655         return 0;
656 }
657
658 static void orion_wdt_shutdown(struct platform_device *pdev)
659 {
660         struct watchdog_device *wdt_dev = platform_get_drvdata(pdev);
661         orion_wdt_stop(wdt_dev);
662 }
663
664 static struct platform_driver orion_wdt_driver = {
665         .probe          = orion_wdt_probe,
666         .remove         = orion_wdt_remove,
667         .shutdown       = orion_wdt_shutdown,
668         .driver         = {
669                 .name   = "orion_wdt",
670                 .of_match_table = orion_wdt_of_match_table,
671         },
672 };
673
674 module_platform_driver(orion_wdt_driver);
675
676 MODULE_AUTHOR("Sylver Bruneau <sylver.bruneau@googlemail.com>");
677 MODULE_DESCRIPTION("Orion Processor Watchdog");
678
679 module_param(heartbeat, int, 0);
680 MODULE_PARM_DESC(heartbeat, "Initial watchdog heartbeat in seconds");
681
682 module_param(nowayout, bool, 0);
683 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
684                                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
685
686 MODULE_LICENSE("GPL v2");
687 MODULE_ALIAS("platform:orion_wdt");