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v3.1
  1/*
  2 * Real Time Clock interface for StrongARM SA1x00 and XScale PXA2xx
  3 *
  4 * Copyright (c) 2000 Nils Faerber
  5 *
  6 * Based on rtc.c by Paul Gortmaker
  7 *
  8 * Original Driver by Nils Faerber <nils@kernelconcepts.de>
  9 *
 10 * Modifications from:
 11 *   CIH <cih@coventive.com>
 12 *   Nicolas Pitre <nico@fluxnic.net>
 13 *   Andrew Christian <andrew.christian@hp.com>
 14 *
 15 * Converted to the RTC subsystem and Driver Model
 16 *   by Richard Purdie <rpurdie@rpsys.net>
 17 *
 18 * This program is free software; you can redistribute it and/or
 19 * modify it under the terms of the GNU General Public License
 20 * as published by the Free Software Foundation; either version
 21 * 2 of the License, or (at your option) any later version.
 22 */
 23
 24#include <linux/platform_device.h>
 25#include <linux/module.h>
 
 26#include <linux/rtc.h>
 27#include <linux/init.h>
 28#include <linux/fs.h>
 29#include <linux/interrupt.h>
 
 30#include <linux/string.h>
 
 31#include <linux/pm.h>
 32#include <linux/bitops.h>
 
 33
 34#include <mach/hardware.h>
 35#include <asm/irq.h>
 
 
 36
 37#ifdef CONFIG_ARCH_PXA
 38#include <mach/regs-rtc.h>
 39#include <mach/regs-ost.h>
 40#endif
 41
 42#define RTC_DEF_DIVIDER		(32768 - 1)
 43#define RTC_DEF_TRIM		0
 
 44
 45static const unsigned long RTC_FREQ = 1024;
 46static struct rtc_time rtc_alarm;
 47static DEFINE_SPINLOCK(sa1100_rtc_lock);
 48
 49static inline int rtc_periodic_alarm(struct rtc_time *tm)
 50{
 51	return  (tm->tm_year == -1) ||
 52		((unsigned)tm->tm_mon >= 12) ||
 53		((unsigned)(tm->tm_mday - 1) >= 31) ||
 54		((unsigned)tm->tm_hour > 23) ||
 55		((unsigned)tm->tm_min > 59) ||
 56		((unsigned)tm->tm_sec > 59);
 57}
 58
 59/*
 60 * Calculate the next alarm time given the requested alarm time mask
 61 * and the current time.
 62 */
 63static void rtc_next_alarm_time(struct rtc_time *next, struct rtc_time *now,
 64	struct rtc_time *alrm)
 65{
 66	unsigned long next_time;
 67	unsigned long now_time;
 68
 69	next->tm_year = now->tm_year;
 70	next->tm_mon = now->tm_mon;
 71	next->tm_mday = now->tm_mday;
 72	next->tm_hour = alrm->tm_hour;
 73	next->tm_min = alrm->tm_min;
 74	next->tm_sec = alrm->tm_sec;
 75
 76	rtc_tm_to_time(now, &now_time);
 77	rtc_tm_to_time(next, &next_time);
 78
 79	if (next_time < now_time) {
 80		/* Advance one day */
 81		next_time += 60 * 60 * 24;
 82		rtc_time_to_tm(next_time, next);
 83	}
 84}
 85
 86static int rtc_update_alarm(struct rtc_time *alrm)
 87{
 88	struct rtc_time alarm_tm, now_tm;
 89	unsigned long now, time;
 90	int ret;
 91
 92	do {
 93		now = RCNR;
 94		rtc_time_to_tm(now, &now_tm);
 95		rtc_next_alarm_time(&alarm_tm, &now_tm, alrm);
 96		ret = rtc_tm_to_time(&alarm_tm, &time);
 97		if (ret != 0)
 98			break;
 99
100		RTSR = RTSR & (RTSR_HZE|RTSR_ALE|RTSR_AL);
101		RTAR = time;
102	} while (now != RCNR);
103
104	return ret;
105}
106
107static irqreturn_t sa1100_rtc_interrupt(int irq, void *dev_id)
108{
109	struct platform_device *pdev = to_platform_device(dev_id);
110	struct rtc_device *rtc = platform_get_drvdata(pdev);
111	unsigned int rtsr;
112	unsigned long events = 0;
113
114	spin_lock(&sa1100_rtc_lock);
115
116	rtsr = RTSR;
117	/* clear interrupt sources */
118	RTSR = 0;
119	/* Fix for a nasty initialization problem the in SA11xx RTSR register.
120	 * See also the comments in sa1100_rtc_probe(). */
121	if (rtsr & (RTSR_ALE | RTSR_HZE)) {
122		/* This is the original code, before there was the if test
123		 * above. This code does not clear interrupts that were not
124		 * enabled. */
125		RTSR = (RTSR_AL | RTSR_HZ) & (rtsr >> 2);
126	} else {
127		/* For some reason, it is possible to enter this routine
128		 * without interruptions enabled, it has been tested with
129		 * several units (Bug in SA11xx chip?).
130		 *
131		 * This situation leads to an infinite "loop" of interrupt
132		 * routine calling and as a result the processor seems to
133		 * lock on its first call to open(). */
134		RTSR = RTSR_AL | RTSR_HZ;
135	}
136
137	/* clear alarm interrupt if it has occurred */
138	if (rtsr & RTSR_AL)
139		rtsr &= ~RTSR_ALE;
140	RTSR = rtsr & (RTSR_ALE | RTSR_HZE);
141
142	/* update irq data & counter */
143	if (rtsr & RTSR_AL)
144		events |= RTC_AF | RTC_IRQF;
145	if (rtsr & RTSR_HZ)
146		events |= RTC_UF | RTC_IRQF;
147
148	rtc_update_irq(rtc, 1, events);
149
150	if (rtsr & RTSR_AL && rtc_periodic_alarm(&rtc_alarm))
151		rtc_update_alarm(&rtc_alarm);
152
153	spin_unlock(&sa1100_rtc_lock);
154
155	return IRQ_HANDLED;
156}
157
158static int sa1100_rtc_open(struct device *dev)
159{
 
 
160	int ret;
161	struct platform_device *plat_dev = to_platform_device(dev);
162	struct rtc_device *rtc = platform_get_drvdata(plat_dev);
163
164	ret = request_irq(IRQ_RTC1Hz, sa1100_rtc_interrupt, IRQF_DISABLED,
165		"rtc 1Hz", dev);
166	if (ret) {
167		dev_err(dev, "IRQ %d already in use.\n", IRQ_RTC1Hz);
168		goto fail_ui;
169	}
170	ret = request_irq(IRQ_RTCAlrm, sa1100_rtc_interrupt, IRQF_DISABLED,
171		"rtc Alrm", dev);
172	if (ret) {
173		dev_err(dev, "IRQ %d already in use.\n", IRQ_RTCAlrm);
174		goto fail_ai;
175	}
176	rtc->max_user_freq = RTC_FREQ;
177	rtc_irq_set_freq(rtc, NULL, RTC_FREQ);
178
179	return 0;
180
181 fail_ai:
182	free_irq(IRQ_RTC1Hz, dev);
183 fail_ui:
 
184	return ret;
185}
186
187static void sa1100_rtc_release(struct device *dev)
188{
189	spin_lock_irq(&sa1100_rtc_lock);
190	RTSR = 0;
191	OIER &= ~OIER_E1;
192	OSSR = OSSR_M1;
193	spin_unlock_irq(&sa1100_rtc_lock);
194
195	free_irq(IRQ_RTCAlrm, dev);
196	free_irq(IRQ_RTC1Hz, dev);
197}
198
199static int sa1100_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
200{
201	spin_lock_irq(&sa1100_rtc_lock);
 
 
 
 
202	if (enabled)
203		RTSR |= RTSR_ALE;
204	else
205		RTSR &= ~RTSR_ALE;
206	spin_unlock_irq(&sa1100_rtc_lock);
 
207	return 0;
208}
209
210static int sa1100_rtc_read_time(struct device *dev, struct rtc_time *tm)
211{
212	rtc_time_to_tm(RCNR, tm);
 
 
213	return 0;
214}
215
216static int sa1100_rtc_set_time(struct device *dev, struct rtc_time *tm)
217{
 
218	unsigned long time;
219	int ret;
220
221	ret = rtc_tm_to_time(tm, &time);
222	if (ret == 0)
223		RCNR = time;
224	return ret;
225}
226
227static int sa1100_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
228{
229	u32	rtsr;
 
230
231	memcpy(&alrm->time, &rtc_alarm, sizeof(struct rtc_time));
232	rtsr = RTSR;
233	alrm->enabled = (rtsr & RTSR_ALE) ? 1 : 0;
234	alrm->pending = (rtsr & RTSR_AL) ? 1 : 0;
235	return 0;
236}
237
238static int sa1100_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
239{
 
 
240	int ret;
241
242	spin_lock_irq(&sa1100_rtc_lock);
243	ret = rtc_update_alarm(&alrm->time);
244	if (ret == 0) {
245		if (alrm->enabled)
246			RTSR |= RTSR_ALE;
247		else
248			RTSR &= ~RTSR_ALE;
249	}
250	spin_unlock_irq(&sa1100_rtc_lock);
 
 
 
 
251
252	return ret;
253}
254
255static int sa1100_rtc_proc(struct device *dev, struct seq_file *seq)
256{
257	seq_printf(seq, "trim/divider\t\t: 0x%08x\n", (u32) RTTR);
258	seq_printf(seq, "RTSR\t\t\t: 0x%08x\n", (u32)RTSR);
 
 
259
260	return 0;
261}
262
263static const struct rtc_class_ops sa1100_rtc_ops = {
264	.open = sa1100_rtc_open,
265	.release = sa1100_rtc_release,
266	.read_time = sa1100_rtc_read_time,
267	.set_time = sa1100_rtc_set_time,
268	.read_alarm = sa1100_rtc_read_alarm,
269	.set_alarm = sa1100_rtc_set_alarm,
270	.proc = sa1100_rtc_proc,
271	.alarm_irq_enable = sa1100_rtc_alarm_irq_enable,
272};
273
274static int sa1100_rtc_probe(struct platform_device *pdev)
275{
276	struct rtc_device *rtc;
 
 
 
 
 
 
 
 
 
277
 
 
 
278	/*
279	 * According to the manual we should be able to let RTTR be zero
280	 * and then a default diviser for a 32.768KHz clock is used.
281	 * Apparently this doesn't work, at least for my SA1110 rev 5.
282	 * If the clock divider is uninitialized then reset it to the
283	 * default value to get the 1Hz clock.
284	 */
285	if (RTTR == 0) {
286		RTTR = RTC_DEF_DIVIDER + (RTC_DEF_TRIM << 16);
287		dev_warn(&pdev->dev, "warning: "
288			"initializing default clock divider/trim value\n");
289		/* The current RTC value probably doesn't make sense either */
290		RCNR = 0;
291	}
292
293	device_init_wakeup(&pdev->dev, 1);
294
295	rtc = rtc_device_register(pdev->name, &pdev->dev, &sa1100_rtc_ops,
296		THIS_MODULE);
297
298	if (IS_ERR(rtc))
299		return PTR_ERR(rtc);
300
301	platform_set_drvdata(pdev, rtc);
302
303	/* Fix for a nasty initialization problem the in SA11xx RTSR register.
304	 * See also the comments in sa1100_rtc_interrupt().
305	 *
306	 * Sometimes bit 1 of the RTSR (RTSR_HZ) will wake up 1, which means an
307	 * interrupt pending, even though interrupts were never enabled.
308	 * In this case, this bit it must be reset before enabling
309	 * interruptions to avoid a nonexistent interrupt to occur.
310	 *
311	 * In principle, the same problem would apply to bit 0, although it has
312	 * never been observed to happen.
313	 *
314	 * This issue is addressed both here and in sa1100_rtc_interrupt().
315	 * If the issue is not addressed here, in the times when the processor
316	 * wakes up with the bit set there will be one spurious interrupt.
317	 *
318	 * The issue is also dealt with in sa1100_rtc_interrupt() to be on the
319	 * safe side, once the condition that lead to this strange
320	 * initialization is unknown and could in principle happen during
321	 * normal processing.
322	 *
323	 * Notice that clearing bit 1 and 0 is accomplished by writting ONES to
324	 * the corresponding bits in RTSR. */
325	RTSR = RTSR_AL | RTSR_HZ;
326
327	return 0;
328}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
329
330static int sa1100_rtc_remove(struct platform_device *pdev)
331{
332	struct rtc_device *rtc = platform_get_drvdata(pdev);
333
334	if (rtc)
335		rtc_device_unregister(rtc);
336
337	return 0;
338}
339
340#ifdef CONFIG_PM
341static int sa1100_rtc_suspend(struct device *dev)
342{
 
343	if (device_may_wakeup(dev))
344		enable_irq_wake(IRQ_RTCAlrm);
345	return 0;
346}
347
348static int sa1100_rtc_resume(struct device *dev)
349{
 
350	if (device_may_wakeup(dev))
351		disable_irq_wake(IRQ_RTCAlrm);
352	return 0;
353}
 
354
355static const struct dev_pm_ops sa1100_rtc_pm_ops = {
356	.suspend	= sa1100_rtc_suspend,
357	.resume		= sa1100_rtc_resume,
 
 
 
 
 
358};
 
359#endif
360
361static struct platform_driver sa1100_rtc_driver = {
362	.probe		= sa1100_rtc_probe,
363	.remove		= sa1100_rtc_remove,
364	.driver		= {
365		.name	= "sa1100-rtc",
366#ifdef CONFIG_PM
367		.pm	= &sa1100_rtc_pm_ops,
368#endif
369	},
370};
371
372static int __init sa1100_rtc_init(void)
373{
374	return platform_driver_register(&sa1100_rtc_driver);
375}
376
377static void __exit sa1100_rtc_exit(void)
378{
379	platform_driver_unregister(&sa1100_rtc_driver);
380}
381
382module_init(sa1100_rtc_init);
383module_exit(sa1100_rtc_exit);
384
385MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
386MODULE_DESCRIPTION("SA11x0/PXA2xx Realtime Clock Driver (RTC)");
387MODULE_LICENSE("GPL");
388MODULE_ALIAS("platform:sa1100-rtc");
v4.10.11
  1/*
  2 * Real Time Clock interface for StrongARM SA1x00 and XScale PXA2xx
  3 *
  4 * Copyright (c) 2000 Nils Faerber
  5 *
  6 * Based on rtc.c by Paul Gortmaker
  7 *
  8 * Original Driver by Nils Faerber <nils@kernelconcepts.de>
  9 *
 10 * Modifications from:
 11 *   CIH <cih@coventive.com>
 12 *   Nicolas Pitre <nico@fluxnic.net>
 13 *   Andrew Christian <andrew.christian@hp.com>
 14 *
 15 * Converted to the RTC subsystem and Driver Model
 16 *   by Richard Purdie <rpurdie@rpsys.net>
 17 *
 18 * This program is free software; you can redistribute it and/or
 19 * modify it under the terms of the GNU General Public License
 20 * as published by the Free Software Foundation; either version
 21 * 2 of the License, or (at your option) any later version.
 22 */
 23
 24#include <linux/platform_device.h>
 25#include <linux/module.h>
 26#include <linux/clk.h>
 27#include <linux/rtc.h>
 28#include <linux/init.h>
 29#include <linux/fs.h>
 30#include <linux/interrupt.h>
 31#include <linux/slab.h>
 32#include <linux/string.h>
 33#include <linux/of.h>
 34#include <linux/pm.h>
 35#include <linux/bitops.h>
 36#include <linux/io.h>
 37
 38#define RTSR_HZE		BIT(3)	/* HZ interrupt enable */
 39#define RTSR_ALE		BIT(2)	/* RTC alarm interrupt enable */
 40#define RTSR_HZ			BIT(1)	/* HZ rising-edge detected */
 41#define RTSR_AL			BIT(0)	/* RTC alarm detected */
 42
 43#include "rtc-sa1100.h"
 
 
 
 44
 45#define RTC_DEF_DIVIDER		(32768 - 1)
 46#define RTC_DEF_TRIM		0
 47#define RTC_FREQ		1024
 48
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 49
 50static irqreturn_t sa1100_rtc_interrupt(int irq, void *dev_id)
 51{
 52	struct sa1100_rtc *info = dev_get_drvdata(dev_id);
 53	struct rtc_device *rtc = info->rtc;
 54	unsigned int rtsr;
 55	unsigned long events = 0;
 56
 57	spin_lock(&info->lock);
 58
 59	rtsr = readl_relaxed(info->rtsr);
 60	/* clear interrupt sources */
 61	writel_relaxed(0, info->rtsr);
 62	/* Fix for a nasty initialization problem the in SA11xx RTSR register.
 63	 * See also the comments in sa1100_rtc_probe(). */
 64	if (rtsr & (RTSR_ALE | RTSR_HZE)) {
 65		/* This is the original code, before there was the if test
 66		 * above. This code does not clear interrupts that were not
 67		 * enabled. */
 68		writel_relaxed((RTSR_AL | RTSR_HZ) & (rtsr >> 2), info->rtsr);
 69	} else {
 70		/* For some reason, it is possible to enter this routine
 71		 * without interruptions enabled, it has been tested with
 72		 * several units (Bug in SA11xx chip?).
 73		 *
 74		 * This situation leads to an infinite "loop" of interrupt
 75		 * routine calling and as a result the processor seems to
 76		 * lock on its first call to open(). */
 77		writel_relaxed(RTSR_AL | RTSR_HZ, info->rtsr);
 78	}
 79
 80	/* clear alarm interrupt if it has occurred */
 81	if (rtsr & RTSR_AL)
 82		rtsr &= ~RTSR_ALE;
 83	writel_relaxed(rtsr & (RTSR_ALE | RTSR_HZE), info->rtsr);
 84
 85	/* update irq data & counter */
 86	if (rtsr & RTSR_AL)
 87		events |= RTC_AF | RTC_IRQF;
 88	if (rtsr & RTSR_HZ)
 89		events |= RTC_UF | RTC_IRQF;
 90
 91	rtc_update_irq(rtc, 1, events);
 92
 93	spin_unlock(&info->lock);
 
 
 
 94
 95	return IRQ_HANDLED;
 96}
 97
 98static int sa1100_rtc_open(struct device *dev)
 99{
100	struct sa1100_rtc *info = dev_get_drvdata(dev);
101	struct rtc_device *rtc = info->rtc;
102	int ret;
 
 
103
104	ret = request_irq(info->irq_1hz, sa1100_rtc_interrupt, 0, "rtc 1Hz", dev);
 
105	if (ret) {
106		dev_err(dev, "IRQ %d already in use.\n", info->irq_1hz);
107		goto fail_ui;
108	}
109	ret = request_irq(info->irq_alarm, sa1100_rtc_interrupt, 0, "rtc Alrm", dev);
 
110	if (ret) {
111		dev_err(dev, "IRQ %d already in use.\n", info->irq_alarm);
112		goto fail_ai;
113	}
114	rtc->max_user_freq = RTC_FREQ;
115	rtc_irq_set_freq(rtc, NULL, RTC_FREQ);
116
117	return 0;
118
119 fail_ai:
120	free_irq(info->irq_1hz, dev);
121 fail_ui:
122	clk_disable_unprepare(info->clk);
123	return ret;
124}
125
126static void sa1100_rtc_release(struct device *dev)
127{
128	struct sa1100_rtc *info = dev_get_drvdata(dev);
129
130	spin_lock_irq(&info->lock);
131	writel_relaxed(0, info->rtsr);
132	spin_unlock_irq(&info->lock);
133
134	free_irq(info->irq_alarm, dev);
135	free_irq(info->irq_1hz, dev);
136}
137
138static int sa1100_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
139{
140	u32 rtsr;
141	struct sa1100_rtc *info = dev_get_drvdata(dev);
142
143	spin_lock_irq(&info->lock);
144	rtsr = readl_relaxed(info->rtsr);
145	if (enabled)
146		rtsr |= RTSR_ALE;
147	else
148		rtsr &= ~RTSR_ALE;
149	writel_relaxed(rtsr, info->rtsr);
150	spin_unlock_irq(&info->lock);
151	return 0;
152}
153
154static int sa1100_rtc_read_time(struct device *dev, struct rtc_time *tm)
155{
156	struct sa1100_rtc *info = dev_get_drvdata(dev);
157
158	rtc_time_to_tm(readl_relaxed(info->rcnr), tm);
159	return 0;
160}
161
162static int sa1100_rtc_set_time(struct device *dev, struct rtc_time *tm)
163{
164	struct sa1100_rtc *info = dev_get_drvdata(dev);
165	unsigned long time;
166	int ret;
167
168	ret = rtc_tm_to_time(tm, &time);
169	if (ret == 0)
170		writel_relaxed(time, info->rcnr);
171	return ret;
172}
173
174static int sa1100_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
175{
176	u32	rtsr;
177	struct sa1100_rtc *info = dev_get_drvdata(dev);
178
179	rtsr = readl_relaxed(info->rtsr);
 
180	alrm->enabled = (rtsr & RTSR_ALE) ? 1 : 0;
181	alrm->pending = (rtsr & RTSR_AL) ? 1 : 0;
182	return 0;
183}
184
185static int sa1100_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
186{
187	struct sa1100_rtc *info = dev_get_drvdata(dev);
188	unsigned long time;
189	int ret;
190
191	spin_lock_irq(&info->lock);
192	ret = rtc_tm_to_time(&alrm->time, &time);
193	if (ret != 0)
194		goto out;
195	writel_relaxed(readl_relaxed(info->rtsr) &
196		(RTSR_HZE | RTSR_ALE | RTSR_AL), info->rtsr);
197	writel_relaxed(time, info->rtar);
198	if (alrm->enabled)
199		writel_relaxed(readl_relaxed(info->rtsr) | RTSR_ALE, info->rtsr);
200	else
201		writel_relaxed(readl_relaxed(info->rtsr) & ~RTSR_ALE, info->rtsr);
202out:
203	spin_unlock_irq(&info->lock);
204
205	return ret;
206}
207
208static int sa1100_rtc_proc(struct device *dev, struct seq_file *seq)
209{
210	struct sa1100_rtc *info = dev_get_drvdata(dev);
211
212	seq_printf(seq, "trim/divider\t\t: 0x%08x\n", readl_relaxed(info->rttr));
213	seq_printf(seq, "RTSR\t\t\t: 0x%08x\n", readl_relaxed(info->rtsr));
214
215	return 0;
216}
217
218static const struct rtc_class_ops sa1100_rtc_ops = {
219	.open = sa1100_rtc_open,
220	.release = sa1100_rtc_release,
221	.read_time = sa1100_rtc_read_time,
222	.set_time = sa1100_rtc_set_time,
223	.read_alarm = sa1100_rtc_read_alarm,
224	.set_alarm = sa1100_rtc_set_alarm,
225	.proc = sa1100_rtc_proc,
226	.alarm_irq_enable = sa1100_rtc_alarm_irq_enable,
227};
228
229int sa1100_rtc_init(struct platform_device *pdev, struct sa1100_rtc *info)
230{
231	struct rtc_device *rtc;
232	int ret;
233
234	spin_lock_init(&info->lock);
235
236	info->clk = devm_clk_get(&pdev->dev, NULL);
237	if (IS_ERR(info->clk)) {
238		dev_err(&pdev->dev, "failed to find rtc clock source\n");
239		return PTR_ERR(info->clk);
240	}
241
242	ret = clk_prepare_enable(info->clk);
243	if (ret)
244		return ret;
245	/*
246	 * According to the manual we should be able to let RTTR be zero
247	 * and then a default diviser for a 32.768KHz clock is used.
248	 * Apparently this doesn't work, at least for my SA1110 rev 5.
249	 * If the clock divider is uninitialized then reset it to the
250	 * default value to get the 1Hz clock.
251	 */
252	if (readl_relaxed(info->rttr) == 0) {
253		writel_relaxed(RTC_DEF_DIVIDER + (RTC_DEF_TRIM << 16), info->rttr);
254		dev_warn(&pdev->dev, "warning: "
255			"initializing default clock divider/trim value\n");
256		/* The current RTC value probably doesn't make sense either */
257		writel_relaxed(0, info->rcnr);
258	}
259
260	rtc = devm_rtc_device_register(&pdev->dev, pdev->name, &sa1100_rtc_ops,
261					THIS_MODULE);
262	if (IS_ERR(rtc)) {
263		clk_disable_unprepare(info->clk);
 
 
264		return PTR_ERR(rtc);
265	}
266	info->rtc = rtc;
267
268	/* Fix for a nasty initialization problem the in SA11xx RTSR register.
269	 * See also the comments in sa1100_rtc_interrupt().
270	 *
271	 * Sometimes bit 1 of the RTSR (RTSR_HZ) will wake up 1, which means an
272	 * interrupt pending, even though interrupts were never enabled.
273	 * In this case, this bit it must be reset before enabling
274	 * interruptions to avoid a nonexistent interrupt to occur.
275	 *
276	 * In principle, the same problem would apply to bit 0, although it has
277	 * never been observed to happen.
278	 *
279	 * This issue is addressed both here and in sa1100_rtc_interrupt().
280	 * If the issue is not addressed here, in the times when the processor
281	 * wakes up with the bit set there will be one spurious interrupt.
282	 *
283	 * The issue is also dealt with in sa1100_rtc_interrupt() to be on the
284	 * safe side, once the condition that lead to this strange
285	 * initialization is unknown and could in principle happen during
286	 * normal processing.
287	 *
288	 * Notice that clearing bit 1 and 0 is accomplished by writting ONES to
289	 * the corresponding bits in RTSR. */
290	writel_relaxed(RTSR_AL | RTSR_HZ, info->rtsr);
291
292	return 0;
293}
294EXPORT_SYMBOL_GPL(sa1100_rtc_init);
295
296static int sa1100_rtc_probe(struct platform_device *pdev)
297{
298	struct sa1100_rtc *info;
299	struct resource *iores;
300	void __iomem *base;
301	int irq_1hz, irq_alarm;
302
303	irq_1hz = platform_get_irq_byname(pdev, "rtc 1Hz");
304	irq_alarm = platform_get_irq_byname(pdev, "rtc alarm");
305	if (irq_1hz < 0 || irq_alarm < 0)
306		return -ENODEV;
307
308	info = devm_kzalloc(&pdev->dev, sizeof(struct sa1100_rtc), GFP_KERNEL);
309	if (!info)
310		return -ENOMEM;
311	info->irq_1hz = irq_1hz;
312	info->irq_alarm = irq_alarm;
313
314	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
315	base = devm_ioremap_resource(&pdev->dev, iores);
316	if (IS_ERR(base))
317		return PTR_ERR(base);
318
319	if (IS_ENABLED(CONFIG_ARCH_SA1100) ||
320	    of_device_is_compatible(pdev->dev.of_node, "mrvl,sa1100-rtc")) {
321		info->rcnr = base + 0x04;
322		info->rtsr = base + 0x10;
323		info->rtar = base + 0x00;
324		info->rttr = base + 0x08;
325	} else {
326		info->rcnr = base + 0x0;
327		info->rtsr = base + 0x8;
328		info->rtar = base + 0x4;
329		info->rttr = base + 0xc;
330	}
331
332	platform_set_drvdata(pdev, info);
333	device_init_wakeup(&pdev->dev, 1);
334
335	return sa1100_rtc_init(pdev, info);
336}
337
338static int sa1100_rtc_remove(struct platform_device *pdev)
339{
340	struct sa1100_rtc *info = platform_get_drvdata(pdev);
341
342	if (info)
343		clk_disable_unprepare(info->clk);
344
345	return 0;
346}
347
348#ifdef CONFIG_PM_SLEEP
349static int sa1100_rtc_suspend(struct device *dev)
350{
351	struct sa1100_rtc *info = dev_get_drvdata(dev);
352	if (device_may_wakeup(dev))
353		enable_irq_wake(info->irq_alarm);
354	return 0;
355}
356
357static int sa1100_rtc_resume(struct device *dev)
358{
359	struct sa1100_rtc *info = dev_get_drvdata(dev);
360	if (device_may_wakeup(dev))
361		disable_irq_wake(info->irq_alarm);
362	return 0;
363}
364#endif
365
366static SIMPLE_DEV_PM_OPS(sa1100_rtc_pm_ops, sa1100_rtc_suspend,
367			sa1100_rtc_resume);
368
369#ifdef CONFIG_OF
370static const struct of_device_id sa1100_rtc_dt_ids[] = {
371	{ .compatible = "mrvl,sa1100-rtc", },
372	{ .compatible = "mrvl,mmp-rtc", },
373	{}
374};
375MODULE_DEVICE_TABLE(of, sa1100_rtc_dt_ids);
376#endif
377
378static struct platform_driver sa1100_rtc_driver = {
379	.probe		= sa1100_rtc_probe,
380	.remove		= sa1100_rtc_remove,
381	.driver		= {
382		.name	= "sa1100-rtc",
 
383		.pm	= &sa1100_rtc_pm_ops,
384		.of_match_table = of_match_ptr(sa1100_rtc_dt_ids),
385	},
386};
387
388module_platform_driver(sa1100_rtc_driver);
 
 
 
 
 
 
 
 
 
 
 
389
390MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
391MODULE_DESCRIPTION("SA11x0/PXA2xx Realtime Clock Driver (RTC)");
392MODULE_LICENSE("GPL");
393MODULE_ALIAS("platform:sa1100-rtc");