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v6.2
  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
 54static bool nowayout = WATCHDOG_NOWAYOUT;
 55static int heartbeat;		/* module parameter (seconds) */
 56
 57struct orion_watchdog;
 58
 59struct 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
 71struct 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
 81static 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
 99static 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
122static 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
162static 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 frequency 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
185static 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
198static 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
228static 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	reg = dev->data->wdt_enable_bit;
242	if (dev->wdt.info->options & WDIOF_PRETIMEOUT)
243		reg |= TIMER1_ENABLE_BIT;
244	atomic_io_modify(dev->reg + TIMER_CTRL, reg, reg);
245
246	/* Enable reset on watchdog */
247	reg = readl(dev->rstout);
248	reg |= dev->data->rstout_enable_bit;
249	writel(reg, dev->rstout);
250	return 0;
251}
252
253static int orion_start(struct watchdog_device *wdt_dev)
254{
255	struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
256
257	/* Set watchdog duration */
258	writel(dev->clk_rate * wdt_dev->timeout,
259	       dev->reg + dev->data->wdt_counter_offset);
260
261	/* Enable watchdog timer */
262	atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit,
263						dev->data->wdt_enable_bit);
264
265	/* Enable reset on watchdog */
266	atomic_io_modify(dev->rstout, dev->data->rstout_enable_bit,
267				      dev->data->rstout_enable_bit);
268
269	return 0;
270}
271
272static int orion_wdt_start(struct watchdog_device *wdt_dev)
273{
274	struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
275
276	/* There are some per-SoC quirks to handle */
277	return dev->data->start(wdt_dev);
278}
279
280static int orion_stop(struct watchdog_device *wdt_dev)
281{
282	struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
283
284	/* Disable reset on watchdog */
285	atomic_io_modify(dev->rstout, dev->data->rstout_enable_bit, 0);
286
287	/* Disable watchdog timer */
288	atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit, 0);
289
290	return 0;
291}
292
293static int armada375_stop(struct watchdog_device *wdt_dev)
294{
295	struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
296	u32 reg, mask;
297
298	/* Disable reset on watchdog */
299	atomic_io_modify(dev->rstout_mask, dev->data->rstout_mask_bit,
300					   dev->data->rstout_mask_bit);
301	reg = readl(dev->rstout);
302	reg &= ~dev->data->rstout_enable_bit;
303	writel(reg, dev->rstout);
304
305	/* Disable watchdog timer */
306	mask = dev->data->wdt_enable_bit;
307	if (wdt_dev->info->options & WDIOF_PRETIMEOUT)
308		mask |= TIMER1_ENABLE_BIT;
309	atomic_io_modify(dev->reg + TIMER_CTRL, mask, 0);
310
311	return 0;
312}
313
314static int armada370_stop(struct watchdog_device *wdt_dev)
315{
316	struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
317	u32 reg, mask;
318
319	/* Disable reset on watchdog */
320	reg = readl(dev->rstout);
321	reg &= ~dev->data->rstout_enable_bit;
322	writel(reg, dev->rstout);
323
324	/* Disable watchdog timer */
325	mask = dev->data->wdt_enable_bit;
326	if (wdt_dev->info->options & WDIOF_PRETIMEOUT)
327		mask |= TIMER1_ENABLE_BIT;
328	atomic_io_modify(dev->reg + TIMER_CTRL, mask, 0);
329
330	return 0;
331}
332
333static int orion_wdt_stop(struct watchdog_device *wdt_dev)
334{
335	struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
336
337	return dev->data->stop(wdt_dev);
338}
339
340static int orion_enabled(struct orion_watchdog *dev)
341{
342	bool enabled, running;
343
344	enabled = readl(dev->rstout) & dev->data->rstout_enable_bit;
345	running = readl(dev->reg + TIMER_CTRL) & dev->data->wdt_enable_bit;
346
347	return enabled && running;
348}
349
350static int armada375_enabled(struct orion_watchdog *dev)
351{
352	bool masked, enabled, running;
353
354	masked = readl(dev->rstout_mask) & dev->data->rstout_mask_bit;
355	enabled = readl(dev->rstout) & dev->data->rstout_enable_bit;
356	running = readl(dev->reg + TIMER_CTRL) & dev->data->wdt_enable_bit;
357
358	return !masked && enabled && running;
359}
360
361static int orion_wdt_enabled(struct watchdog_device *wdt_dev)
362{
363	struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
364
365	return dev->data->enabled(dev);
366}
367
368static unsigned int orion_wdt_get_timeleft(struct watchdog_device *wdt_dev)
369{
370	struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
371	return readl(dev->reg + dev->data->wdt_counter_offset) / dev->clk_rate;
372}
373
374static struct watchdog_info orion_wdt_info = {
375	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
376	.identity = "Orion Watchdog",
377};
378
379static const struct watchdog_ops orion_wdt_ops = {
380	.owner = THIS_MODULE,
381	.start = orion_wdt_start,
382	.stop = orion_wdt_stop,
383	.ping = orion_wdt_ping,
384	.get_timeleft = orion_wdt_get_timeleft,
385};
386
387static irqreturn_t orion_wdt_irq(int irq, void *devid)
388{
389	panic("Watchdog Timeout");
390	return IRQ_HANDLED;
391}
392
393static irqreturn_t orion_wdt_pre_irq(int irq, void *devid)
394{
395	struct orion_watchdog *dev = devid;
396
397	atomic_io_modify(dev->reg + TIMER_A370_STATUS,
398			 TIMER1_STATUS_BIT, 0);
399	watchdog_notify_pretimeout(&dev->wdt);
400	return IRQ_HANDLED;
401}
402
403/*
404 * The original devicetree binding for this driver specified only
405 * one memory resource, so in order to keep DT backwards compatibility
406 * we try to fallback to a hardcoded register address, if the resource
407 * is missing from the devicetree.
408 */
409static void __iomem *orion_wdt_ioremap_rstout(struct platform_device *pdev,
410					      phys_addr_t internal_regs)
411{
412	struct resource *res;
413	phys_addr_t rstout;
414
415	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
416	if (res)
417		return devm_ioremap(&pdev->dev, res->start,
418				    resource_size(res));
419
420	rstout = internal_regs + ORION_RSTOUT_MASK_OFFSET;
421
422	WARN(1, FW_BUG "falling back to hardcoded RSTOUT reg %pa\n", &rstout);
423	return devm_ioremap(&pdev->dev, rstout, 0x4);
424}
425
426static const struct orion_watchdog_data orion_data = {
427	.rstout_enable_bit = BIT(1),
428	.wdt_enable_bit = BIT(4),
429	.wdt_counter_offset = 0x24,
430	.clock_init = orion_wdt_clock_init,
431	.enabled = orion_enabled,
432	.start = orion_start,
433	.stop = orion_stop,
434};
435
436static const struct orion_watchdog_data armada370_data = {
437	.rstout_enable_bit = BIT(8),
438	.wdt_enable_bit = BIT(8),
439	.wdt_counter_offset = 0x34,
440	.clock_init = armada370_wdt_clock_init,
441	.enabled = orion_enabled,
442	.start = armada370_start,
443	.stop = armada370_stop,
444};
445
446static const struct orion_watchdog_data armadaxp_data = {
447	.rstout_enable_bit = BIT(8),
448	.wdt_enable_bit = BIT(8),
449	.wdt_counter_offset = 0x34,
450	.clock_init = armadaxp_wdt_clock_init,
451	.enabled = orion_enabled,
452	.start = armada370_start,
453	.stop = armada370_stop,
454};
455
456static const struct orion_watchdog_data armada375_data = {
457	.rstout_enable_bit = BIT(8),
458	.rstout_mask_bit = BIT(10),
459	.wdt_enable_bit = BIT(8),
460	.wdt_counter_offset = 0x34,
461	.clock_init = armada375_wdt_clock_init,
462	.enabled = armada375_enabled,
463	.start = armada375_start,
464	.stop = armada375_stop,
465};
466
467static const struct orion_watchdog_data armada380_data = {
468	.rstout_enable_bit = BIT(8),
469	.rstout_mask_bit = BIT(10),
470	.wdt_enable_bit = BIT(8),
471	.wdt_counter_offset = 0x34,
472	.clock_init = armadaxp_wdt_clock_init,
473	.enabled = armada375_enabled,
474	.start = armada375_start,
475	.stop = armada375_stop,
476};
477
478static const struct of_device_id orion_wdt_of_match_table[] = {
479	{
480		.compatible = "marvell,orion-wdt",
481		.data = &orion_data,
482	},
483	{
484		.compatible = "marvell,armada-370-wdt",
485		.data = &armada370_data,
486	},
487	{
488		.compatible = "marvell,armada-xp-wdt",
489		.data = &armadaxp_data,
490	},
491	{
492		.compatible = "marvell,armada-375-wdt",
493		.data = &armada375_data,
494	},
495	{
496		.compatible = "marvell,armada-380-wdt",
497		.data = &armada380_data,
498	},
499	{},
500};
501MODULE_DEVICE_TABLE(of, orion_wdt_of_match_table);
502
503static int orion_wdt_get_regs(struct platform_device *pdev,
504			      struct orion_watchdog *dev)
505{
506	struct device_node *node = pdev->dev.of_node;
507	struct resource *res;
508
509	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
510	if (!res)
511		return -ENODEV;
512	dev->reg = devm_ioremap(&pdev->dev, res->start,
513				resource_size(res));
514	if (!dev->reg)
515		return -ENOMEM;
516
517	/* Each supported compatible has some RSTOUT register quirk */
518	if (of_device_is_compatible(node, "marvell,orion-wdt")) {
519
520		dev->rstout = orion_wdt_ioremap_rstout(pdev, res->start &
521						       INTERNAL_REGS_MASK);
522		if (!dev->rstout)
523			return -ENODEV;
524
525	} else if (of_device_is_compatible(node, "marvell,armada-370-wdt") ||
526		   of_device_is_compatible(node, "marvell,armada-xp-wdt")) {
527
528		/* Dedicated RSTOUT register, can be requested. */
529		dev->rstout = devm_platform_ioremap_resource(pdev, 1);
530		if (IS_ERR(dev->rstout))
531			return PTR_ERR(dev->rstout);
532
533	} else if (of_device_is_compatible(node, "marvell,armada-375-wdt") ||
534		   of_device_is_compatible(node, "marvell,armada-380-wdt")) {
535
536		/* Dedicated RSTOUT register, can be requested. */
537		dev->rstout = devm_platform_ioremap_resource(pdev, 1);
538		if (IS_ERR(dev->rstout))
539			return PTR_ERR(dev->rstout);
540
541		res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
542		if (!res)
543			return -ENODEV;
544		dev->rstout_mask = devm_ioremap(&pdev->dev, res->start,
545						resource_size(res));
546		if (!dev->rstout_mask)
547			return -ENOMEM;
548
549	} else {
550		return -ENODEV;
551	}
552
553	return 0;
554}
555
556static int orion_wdt_probe(struct platform_device *pdev)
557{
558	struct orion_watchdog *dev;
559	const struct of_device_id *match;
560	unsigned int wdt_max_duration;	/* (seconds) */
561	int ret, irq;
562
563	dev = devm_kzalloc(&pdev->dev, sizeof(struct orion_watchdog),
564			   GFP_KERNEL);
565	if (!dev)
566		return -ENOMEM;
567
568	match = of_match_device(orion_wdt_of_match_table, &pdev->dev);
569	if (!match)
570		/* Default legacy match */
571		match = &orion_wdt_of_match_table[0];
572
573	dev->wdt.info = &orion_wdt_info;
574	dev->wdt.ops = &orion_wdt_ops;
575	dev->wdt.min_timeout = 1;
576	dev->data = match->data;
577
578	ret = orion_wdt_get_regs(pdev, dev);
579	if (ret)
580		return ret;
581
582	ret = dev->data->clock_init(pdev, dev);
583	if (ret) {
584		dev_err(&pdev->dev, "cannot initialize clock\n");
585		return ret;
586	}
587
588	wdt_max_duration = WDT_MAX_CYCLE_COUNT / dev->clk_rate;
589
590	dev->wdt.timeout = wdt_max_duration;
591	dev->wdt.max_timeout = wdt_max_duration;
592	dev->wdt.parent = &pdev->dev;
593	watchdog_init_timeout(&dev->wdt, heartbeat, &pdev->dev);
594
595	platform_set_drvdata(pdev, &dev->wdt);
596	watchdog_set_drvdata(&dev->wdt, dev);
597
598	/*
599	 * Let's make sure the watchdog is fully stopped, unless it's
600	 * explicitly enabled. This may be the case if the module was
601	 * removed and re-inserted, or if the bootloader explicitly
602	 * set a running watchdog before booting the kernel.
603	 */
604	if (!orion_wdt_enabled(&dev->wdt))
605		orion_wdt_stop(&dev->wdt);
606	else
607		set_bit(WDOG_HW_RUNNING, &dev->wdt.status);
608
609	/* Request the IRQ only after the watchdog is disabled */
610	irq = platform_get_irq_optional(pdev, 0);
611	if (irq > 0) {
612		/*
613		 * Not all supported platforms specify an interrupt for the
614		 * watchdog, so let's make it optional.
615		 */
616		ret = devm_request_irq(&pdev->dev, irq, orion_wdt_irq, 0,
617				       pdev->name, dev);
618		if (ret < 0) {
619			dev_err(&pdev->dev, "failed to request IRQ\n");
620			goto disable_clk;
621		}
622	}
623
624	/* Optional 2nd interrupt for pretimeout */
625	irq = platform_get_irq_optional(pdev, 1);
626	if (irq > 0) {
627		orion_wdt_info.options |= WDIOF_PRETIMEOUT;
628		ret = devm_request_irq(&pdev->dev, irq, orion_wdt_pre_irq,
629				       0, pdev->name, dev);
630		if (ret < 0) {
631			dev_err(&pdev->dev, "failed to request IRQ\n");
632			goto disable_clk;
633		}
634	}
635
636
637	watchdog_set_nowayout(&dev->wdt, nowayout);
638	ret = watchdog_register_device(&dev->wdt);
639	if (ret)
640		goto disable_clk;
641
642	pr_info("Initial timeout %d sec%s\n",
643		dev->wdt.timeout, nowayout ? ", nowayout" : "");
644	return 0;
645
646disable_clk:
647	clk_disable_unprepare(dev->clk);
648	clk_put(dev->clk);
649	return ret;
650}
651
652static int orion_wdt_remove(struct platform_device *pdev)
653{
654	struct watchdog_device *wdt_dev = platform_get_drvdata(pdev);
655	struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
656
657	watchdog_unregister_device(wdt_dev);
658	clk_disable_unprepare(dev->clk);
659	clk_put(dev->clk);
660	return 0;
661}
662
663static void orion_wdt_shutdown(struct platform_device *pdev)
664{
665	struct watchdog_device *wdt_dev = platform_get_drvdata(pdev);
666	orion_wdt_stop(wdt_dev);
667}
668
669static struct platform_driver orion_wdt_driver = {
670	.probe		= orion_wdt_probe,
671	.remove		= orion_wdt_remove,
672	.shutdown	= orion_wdt_shutdown,
673	.driver		= {
674		.name	= "orion_wdt",
675		.of_match_table = orion_wdt_of_match_table,
676	},
677};
678
679module_platform_driver(orion_wdt_driver);
680
681MODULE_AUTHOR("Sylver Bruneau <sylver.bruneau@googlemail.com>");
682MODULE_DESCRIPTION("Orion Processor Watchdog");
683
684module_param(heartbeat, int, 0);
685MODULE_PARM_DESC(heartbeat, "Initial watchdog heartbeat in seconds");
686
687module_param(nowayout, bool, 0);
688MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
689				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
690
691MODULE_LICENSE("GPL v2");
692MODULE_ALIAS("platform:orion_wdt");
v5.4
  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
 54static bool nowayout = WATCHDOG_NOWAYOUT;
 55static int heartbeat = -1;		/* module parameter (seconds) */
 56
 57struct orion_watchdog;
 58
 59struct 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
 71struct 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
 81static 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
 99static 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
122static 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
162static 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
185static 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
198static 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
228static 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
251static 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
270static 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
278static 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
291static 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
312static 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
328static 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
335static 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
345static 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
356static 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
363static 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
369static struct watchdog_info orion_wdt_info = {
370	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
371	.identity = "Orion Watchdog",
372};
373
374static 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
382static irqreturn_t orion_wdt_irq(int irq, void *devid)
383{
384	panic("Watchdog Timeout");
385	return IRQ_HANDLED;
386}
387
388static 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 */
404static 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
421static 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
431static 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
441static 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
451static 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
462static 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
473static 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};
496MODULE_DEVICE_TABLE(of, orion_wdt_of_match_table);
497
498static 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
551static 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
641disable_clk:
642	clk_disable_unprepare(dev->clk);
643	clk_put(dev->clk);
644	return ret;
645}
646
647static 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
658static 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
664static 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
674module_platform_driver(orion_wdt_driver);
675
676MODULE_AUTHOR("Sylver Bruneau <sylver.bruneau@googlemail.com>");
677MODULE_DESCRIPTION("Orion Processor Watchdog");
678
679module_param(heartbeat, int, 0);
680MODULE_PARM_DESC(heartbeat, "Initial watchdog heartbeat in seconds");
681
682module_param(nowayout, bool, 0);
683MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
684				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
685
686MODULE_LICENSE("GPL v2");
687MODULE_ALIAS("platform:orion_wdt");