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v4.6
  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");
v4.17
  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_alarm_irq_enable(struct device *dev, unsigned int enabled)
 99{
100	u32 rtsr;
101	struct sa1100_rtc *info = dev_get_drvdata(dev);
102
103	spin_lock_irq(&info->lock);
104	rtsr = readl_relaxed(info->rtsr);
105	if (enabled)
106		rtsr |= RTSR_ALE;
107	else
108		rtsr &= ~RTSR_ALE;
109	writel_relaxed(rtsr, info->rtsr);
110	spin_unlock_irq(&info->lock);
111	return 0;
112}
113
114static int sa1100_rtc_read_time(struct device *dev, struct rtc_time *tm)
115{
116	struct sa1100_rtc *info = dev_get_drvdata(dev);
117
118	rtc_time_to_tm(readl_relaxed(info->rcnr), tm);
119	return 0;
120}
121
122static int sa1100_rtc_set_time(struct device *dev, struct rtc_time *tm)
123{
124	struct sa1100_rtc *info = dev_get_drvdata(dev);
125	unsigned long time;
126	int ret;
127
128	ret = rtc_tm_to_time(tm, &time);
129	if (ret == 0)
130		writel_relaxed(time, info->rcnr);
131	return ret;
132}
133
134static int sa1100_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
135{
136	u32	rtsr;
137	struct sa1100_rtc *info = dev_get_drvdata(dev);
138
139	rtsr = readl_relaxed(info->rtsr);
140	alrm->enabled = (rtsr & RTSR_ALE) ? 1 : 0;
141	alrm->pending = (rtsr & RTSR_AL) ? 1 : 0;
142	return 0;
143}
144
145static int sa1100_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
146{
147	struct sa1100_rtc *info = dev_get_drvdata(dev);
148	unsigned long time;
149	int ret;
150
151	spin_lock_irq(&info->lock);
152	ret = rtc_tm_to_time(&alrm->time, &time);
153	if (ret != 0)
154		goto out;
155	writel_relaxed(readl_relaxed(info->rtsr) &
156		(RTSR_HZE | RTSR_ALE | RTSR_AL), info->rtsr);
157	writel_relaxed(time, info->rtar);
158	if (alrm->enabled)
159		writel_relaxed(readl_relaxed(info->rtsr) | RTSR_ALE, info->rtsr);
160	else
161		writel_relaxed(readl_relaxed(info->rtsr) & ~RTSR_ALE, info->rtsr);
162out:
163	spin_unlock_irq(&info->lock);
164
165	return ret;
166}
167
168static int sa1100_rtc_proc(struct device *dev, struct seq_file *seq)
169{
170	struct sa1100_rtc *info = dev_get_drvdata(dev);
171
172	seq_printf(seq, "trim/divider\t\t: 0x%08x\n", readl_relaxed(info->rttr));
173	seq_printf(seq, "RTSR\t\t\t: 0x%08x\n", readl_relaxed(info->rtsr));
174
175	return 0;
176}
177
178static const struct rtc_class_ops sa1100_rtc_ops = {
 
 
179	.read_time = sa1100_rtc_read_time,
180	.set_time = sa1100_rtc_set_time,
181	.read_alarm = sa1100_rtc_read_alarm,
182	.set_alarm = sa1100_rtc_set_alarm,
183	.proc = sa1100_rtc_proc,
184	.alarm_irq_enable = sa1100_rtc_alarm_irq_enable,
185};
186
187int sa1100_rtc_init(struct platform_device *pdev, struct sa1100_rtc *info)
188{
189	struct rtc_device *rtc;
190	int ret;
191
192	spin_lock_init(&info->lock);
193
194	info->clk = devm_clk_get(&pdev->dev, NULL);
195	if (IS_ERR(info->clk)) {
196		dev_err(&pdev->dev, "failed to find rtc clock source\n");
197		return PTR_ERR(info->clk);
198	}
199
200	ret = clk_prepare_enable(info->clk);
201	if (ret)
202		return ret;
203	/*
204	 * According to the manual we should be able to let RTTR be zero
205	 * and then a default diviser for a 32.768KHz clock is used.
206	 * Apparently this doesn't work, at least for my SA1110 rev 5.
207	 * If the clock divider is uninitialized then reset it to the
208	 * default value to get the 1Hz clock.
209	 */
210	if (readl_relaxed(info->rttr) == 0) {
211		writel_relaxed(RTC_DEF_DIVIDER + (RTC_DEF_TRIM << 16), info->rttr);
212		dev_warn(&pdev->dev, "warning: "
213			"initializing default clock divider/trim value\n");
214		/* The current RTC value probably doesn't make sense either */
215		writel_relaxed(0, info->rcnr);
216	}
217
218	rtc = devm_rtc_device_register(&pdev->dev, pdev->name, &sa1100_rtc_ops,
219					THIS_MODULE);
220	if (IS_ERR(rtc)) {
221		clk_disable_unprepare(info->clk);
222		return PTR_ERR(rtc);
223	}
224	info->rtc = rtc;
225
226	rtc->max_user_freq = RTC_FREQ;
227	rtc_irq_set_freq(rtc, NULL, RTC_FREQ);
228
229	/* Fix for a nasty initialization problem the in SA11xx RTSR register.
230	 * See also the comments in sa1100_rtc_interrupt().
231	 *
232	 * Sometimes bit 1 of the RTSR (RTSR_HZ) will wake up 1, which means an
233	 * interrupt pending, even though interrupts were never enabled.
234	 * In this case, this bit it must be reset before enabling
235	 * interruptions to avoid a nonexistent interrupt to occur.
236	 *
237	 * In principle, the same problem would apply to bit 0, although it has
238	 * never been observed to happen.
239	 *
240	 * This issue is addressed both here and in sa1100_rtc_interrupt().
241	 * If the issue is not addressed here, in the times when the processor
242	 * wakes up with the bit set there will be one spurious interrupt.
243	 *
244	 * The issue is also dealt with in sa1100_rtc_interrupt() to be on the
245	 * safe side, once the condition that lead to this strange
246	 * initialization is unknown and could in principle happen during
247	 * normal processing.
248	 *
249	 * Notice that clearing bit 1 and 0 is accomplished by writting ONES to
250	 * the corresponding bits in RTSR. */
251	writel_relaxed(RTSR_AL | RTSR_HZ, info->rtsr);
252
253	return 0;
254}
255EXPORT_SYMBOL_GPL(sa1100_rtc_init);
256
257static int sa1100_rtc_probe(struct platform_device *pdev)
258{
259	struct sa1100_rtc *info;
260	struct resource *iores;
261	void __iomem *base;
262	int irq_1hz, irq_alarm;
263	int ret;
264
265	irq_1hz = platform_get_irq_byname(pdev, "rtc 1Hz");
266	irq_alarm = platform_get_irq_byname(pdev, "rtc alarm");
267	if (irq_1hz < 0 || irq_alarm < 0)
268		return -ENODEV;
269
270	info = devm_kzalloc(&pdev->dev, sizeof(struct sa1100_rtc), GFP_KERNEL);
271	if (!info)
272		return -ENOMEM;
273	info->irq_1hz = irq_1hz;
274	info->irq_alarm = irq_alarm;
275
276	ret = devm_request_irq(&pdev->dev, irq_1hz, sa1100_rtc_interrupt, 0,
277			       "rtc 1Hz", &pdev->dev);
278	if (ret) {
279		dev_err(&pdev->dev, "IRQ %d already in use.\n", irq_1hz);
280		return ret;
281	}
282	ret = devm_request_irq(&pdev->dev, irq_alarm, sa1100_rtc_interrupt, 0,
283			       "rtc Alrm", &pdev->dev);
284	if (ret) {
285		dev_err(&pdev->dev, "IRQ %d already in use.\n", irq_alarm);
286		return ret;
287	}
288
289	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
290	base = devm_ioremap_resource(&pdev->dev, iores);
291	if (IS_ERR(base))
292		return PTR_ERR(base);
293
294	if (IS_ENABLED(CONFIG_ARCH_SA1100) ||
295	    of_device_is_compatible(pdev->dev.of_node, "mrvl,sa1100-rtc")) {
296		info->rcnr = base + 0x04;
297		info->rtsr = base + 0x10;
298		info->rtar = base + 0x00;
299		info->rttr = base + 0x08;
300	} else {
301		info->rcnr = base + 0x0;
302		info->rtsr = base + 0x8;
303		info->rtar = base + 0x4;
304		info->rttr = base + 0xc;
305	}
306
307	platform_set_drvdata(pdev, info);
308	device_init_wakeup(&pdev->dev, 1);
309
310	return sa1100_rtc_init(pdev, info);
311}
312
313static int sa1100_rtc_remove(struct platform_device *pdev)
314{
315	struct sa1100_rtc *info = platform_get_drvdata(pdev);
316
317	if (info) {
318		spin_lock_irq(&info->lock);
319		writel_relaxed(0, info->rtsr);
320		spin_unlock_irq(&info->lock);
321		clk_disable_unprepare(info->clk);
322	}
323
324	return 0;
325}
326
327#ifdef CONFIG_PM_SLEEP
328static int sa1100_rtc_suspend(struct device *dev)
329{
330	struct sa1100_rtc *info = dev_get_drvdata(dev);
331	if (device_may_wakeup(dev))
332		enable_irq_wake(info->irq_alarm);
333	return 0;
334}
335
336static int sa1100_rtc_resume(struct device *dev)
337{
338	struct sa1100_rtc *info = dev_get_drvdata(dev);
339	if (device_may_wakeup(dev))
340		disable_irq_wake(info->irq_alarm);
341	return 0;
342}
343#endif
344
345static SIMPLE_DEV_PM_OPS(sa1100_rtc_pm_ops, sa1100_rtc_suspend,
346			sa1100_rtc_resume);
347
348#ifdef CONFIG_OF
349static const struct of_device_id sa1100_rtc_dt_ids[] = {
350	{ .compatible = "mrvl,sa1100-rtc", },
351	{ .compatible = "mrvl,mmp-rtc", },
352	{}
353};
354MODULE_DEVICE_TABLE(of, sa1100_rtc_dt_ids);
355#endif
356
357static struct platform_driver sa1100_rtc_driver = {
358	.probe		= sa1100_rtc_probe,
359	.remove		= sa1100_rtc_remove,
360	.driver		= {
361		.name	= "sa1100-rtc",
362		.pm	= &sa1100_rtc_pm_ops,
363		.of_match_table = of_match_ptr(sa1100_rtc_dt_ids),
364	},
365};
366
367module_platform_driver(sa1100_rtc_driver);
368
369MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
370MODULE_DESCRIPTION("SA11x0/PXA2xx Realtime Clock Driver (RTC)");
371MODULE_LICENSE("GPL");
372MODULE_ALIAS("platform:sa1100-rtc");