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v4.6
  1/*
  2 *  Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
  3 *  Copyright (C) 2010, Paul Cercueil <paul@crapouillou.net>
  4 *	 JZ4740 SoC RTC driver
  5 *
  6 *  This program is free software; you can redistribute it and/or modify it
  7 *  under  the terms of  the GNU General Public License as published by the
  8 *  Free Software Foundation;  either version 2 of the License, or (at your
  9 *  option) any later version.
 10 *
 11 *  You should have received a copy of the GNU General Public License along
 12 *  with this program; if not, write to the Free Software Foundation, Inc.,
 13 *  675 Mass Ave, Cambridge, MA 02139, USA.
 14 *
 15 */
 16
 
 17#include <linux/io.h>
 18#include <linux/kernel.h>
 19#include <linux/module.h>
 
 20#include <linux/platform_device.h>
 
 21#include <linux/rtc.h>
 22#include <linux/slab.h>
 23#include <linux/spinlock.h>
 24
 25#define JZ_REG_RTC_CTRL		0x00
 26#define JZ_REG_RTC_SEC		0x04
 27#define JZ_REG_RTC_SEC_ALARM	0x08
 28#define JZ_REG_RTC_REGULATOR	0x0C
 29#define JZ_REG_RTC_HIBERNATE	0x20
 
 
 30#define JZ_REG_RTC_SCRATCHPAD	0x34
 31
 
 
 
 
 32#define JZ_RTC_CTRL_WRDY	BIT(7)
 33#define JZ_RTC_CTRL_1HZ		BIT(6)
 34#define JZ_RTC_CTRL_1HZ_IRQ	BIT(5)
 35#define JZ_RTC_CTRL_AF		BIT(4)
 36#define JZ_RTC_CTRL_AF_IRQ	BIT(3)
 37#define JZ_RTC_CTRL_AE		BIT(2)
 38#define JZ_RTC_CTRL_ENABLE	BIT(0)
 39
 
 
 
 
 
 
 
 
 
 
 
 40struct jz4740_rtc {
 41	void __iomem *base;
 
 42
 43	struct rtc_device *rtc;
 
 44
 45	int irq;
 46
 47	spinlock_t lock;
 
 
 
 48};
 49
 
 
 50static inline uint32_t jz4740_rtc_reg_read(struct jz4740_rtc *rtc, size_t reg)
 51{
 52	return readl(rtc->base + reg);
 53}
 54
 55static int jz4740_rtc_wait_write_ready(struct jz4740_rtc *rtc)
 56{
 57	uint32_t ctrl;
 58	int timeout = 1000;
 59
 60	do {
 61		ctrl = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_CTRL);
 62	} while (!(ctrl & JZ_RTC_CTRL_WRDY) && --timeout);
 63
 64	return timeout ? 0 : -EIO;
 65}
 66
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 67static inline int jz4740_rtc_reg_write(struct jz4740_rtc *rtc, size_t reg,
 68	uint32_t val)
 69{
 70	int ret;
 71	ret = jz4740_rtc_wait_write_ready(rtc);
 
 
 
 
 72	if (ret == 0)
 73		writel(val, rtc->base + reg);
 74
 75	return ret;
 76}
 77
 78static int jz4740_rtc_ctrl_set_bits(struct jz4740_rtc *rtc, uint32_t mask,
 79	bool set)
 80{
 81	int ret;
 82	unsigned long flags;
 83	uint32_t ctrl;
 84
 85	spin_lock_irqsave(&rtc->lock, flags);
 86
 87	ctrl = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_CTRL);
 88
 89	/* Don't clear interrupt flags by accident */
 90	ctrl |= JZ_RTC_CTRL_1HZ | JZ_RTC_CTRL_AF;
 91
 92	if (set)
 93		ctrl |= mask;
 94	else
 95		ctrl &= ~mask;
 96
 97	ret = jz4740_rtc_reg_write(rtc, JZ_REG_RTC_CTRL, ctrl);
 98
 99	spin_unlock_irqrestore(&rtc->lock, flags);
100
101	return ret;
102}
103
104static int jz4740_rtc_read_time(struct device *dev, struct rtc_time *time)
105{
106	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
107	uint32_t secs, secs2;
108	int timeout = 5;
109
110	/* If the seconds register is read while it is updated, it can contain a
111	 * bogus value. This can be avoided by making sure that two consecutive
112	 * reads have the same value.
113	 */
114	secs = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_SEC);
115	secs2 = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_SEC);
116
117	while (secs != secs2 && --timeout) {
118		secs = secs2;
119		secs2 = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_SEC);
120	}
121
122	if (timeout == 0)
123		return -EIO;
124
125	rtc_time_to_tm(secs, time);
126
127	return rtc_valid_tm(time);
128}
129
130static int jz4740_rtc_set_mmss(struct device *dev, unsigned long secs)
131{
132	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
133
134	return jz4740_rtc_reg_write(rtc, JZ_REG_RTC_SEC, secs);
135}
136
137static int jz4740_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
138{
139	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
140	uint32_t secs;
141	uint32_t ctrl;
142
143	secs = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_SEC_ALARM);
144
145	ctrl = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_CTRL);
146
147	alrm->enabled = !!(ctrl & JZ_RTC_CTRL_AE);
148	alrm->pending = !!(ctrl & JZ_RTC_CTRL_AF);
149
150	rtc_time_to_tm(secs, &alrm->time);
151
152	return rtc_valid_tm(&alrm->time);
153}
154
155static int jz4740_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
156{
157	int ret;
158	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
159	unsigned long secs;
160
161	rtc_tm_to_time(&alrm->time, &secs);
162
163	ret = jz4740_rtc_reg_write(rtc, JZ_REG_RTC_SEC_ALARM, secs);
164	if (!ret)
165		ret = jz4740_rtc_ctrl_set_bits(rtc,
166			JZ_RTC_CTRL_AE | JZ_RTC_CTRL_AF_IRQ, alrm->enabled);
167
168	return ret;
169}
170
171static int jz4740_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
172{
173	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
174	return jz4740_rtc_ctrl_set_bits(rtc, JZ_RTC_CTRL_AF_IRQ, enable);
175}
176
177static struct rtc_class_ops jz4740_rtc_ops = {
178	.read_time	= jz4740_rtc_read_time,
179	.set_mmss	= jz4740_rtc_set_mmss,
180	.read_alarm	= jz4740_rtc_read_alarm,
181	.set_alarm	= jz4740_rtc_set_alarm,
182	.alarm_irq_enable = jz4740_rtc_alarm_irq_enable,
183};
184
185static irqreturn_t jz4740_rtc_irq(int irq, void *data)
186{
187	struct jz4740_rtc *rtc = data;
188	uint32_t ctrl;
189	unsigned long events = 0;
190
191	ctrl = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_CTRL);
192
193	if (ctrl & JZ_RTC_CTRL_1HZ)
194		events |= (RTC_UF | RTC_IRQF);
195
196	if (ctrl & JZ_RTC_CTRL_AF)
197		events |= (RTC_AF | RTC_IRQF);
198
199	rtc_update_irq(rtc->rtc, 1, events);
200
201	jz4740_rtc_ctrl_set_bits(rtc, JZ_RTC_CTRL_1HZ | JZ_RTC_CTRL_AF, false);
202
203	return IRQ_HANDLED;
204}
205
206void jz4740_rtc_poweroff(struct device *dev)
207{
208	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
209	jz4740_rtc_reg_write(rtc, JZ_REG_RTC_HIBERNATE, 1);
210}
211EXPORT_SYMBOL_GPL(jz4740_rtc_poweroff);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
212
213static int jz4740_rtc_probe(struct platform_device *pdev)
214{
215	int ret;
216	struct jz4740_rtc *rtc;
217	uint32_t scratchpad;
218	struct resource *mem;
 
 
 
 
219
220	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
221	if (!rtc)
222		return -ENOMEM;
223
 
 
 
 
 
224	rtc->irq = platform_get_irq(pdev, 0);
225	if (rtc->irq < 0) {
226		dev_err(&pdev->dev, "Failed to get platform irq\n");
227		return -ENOENT;
228	}
229
230	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
231	rtc->base = devm_ioremap_resource(&pdev->dev, mem);
232	if (IS_ERR(rtc->base))
233		return PTR_ERR(rtc->base);
234
 
 
 
 
 
 
235	spin_lock_init(&rtc->lock);
236
237	platform_set_drvdata(pdev, rtc);
238
239	device_init_wakeup(&pdev->dev, 1);
240
241	rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
242					&jz4740_rtc_ops, THIS_MODULE);
243	if (IS_ERR(rtc->rtc)) {
244		ret = PTR_ERR(rtc->rtc);
245		dev_err(&pdev->dev, "Failed to register rtc device: %d\n", ret);
246		return ret;
247	}
248
249	ret = devm_request_irq(&pdev->dev, rtc->irq, jz4740_rtc_irq, 0,
250				pdev->name, rtc);
251	if (ret) {
252		dev_err(&pdev->dev, "Failed to request rtc irq: %d\n", ret);
253		return ret;
254	}
255
256	scratchpad = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_SCRATCHPAD);
257	if (scratchpad != 0x12345678) {
258		ret = jz4740_rtc_reg_write(rtc, JZ_REG_RTC_SCRATCHPAD, 0x12345678);
259		ret = jz4740_rtc_reg_write(rtc, JZ_REG_RTC_SEC, 0);
260		if (ret) {
261			dev_err(&pdev->dev, "Could not write write to RTC registers\n");
262			return ret;
263		}
264	}
265
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
266	return 0;
267}
268
269#ifdef CONFIG_PM
270static int jz4740_rtc_suspend(struct device *dev)
271{
272	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
273
274	if (device_may_wakeup(dev))
275		enable_irq_wake(rtc->irq);
276	return 0;
277}
278
279static int jz4740_rtc_resume(struct device *dev)
280{
281	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
282
283	if (device_may_wakeup(dev))
284		disable_irq_wake(rtc->irq);
285	return 0;
286}
287
288static const struct dev_pm_ops jz4740_pm_ops = {
289	.suspend = jz4740_rtc_suspend,
290	.resume  = jz4740_rtc_resume,
291};
292#define JZ4740_RTC_PM_OPS (&jz4740_pm_ops)
293
294#else
295#define JZ4740_RTC_PM_OPS NULL
296#endif  /* CONFIG_PM */
297
 
 
 
 
 
 
 
298static struct platform_driver jz4740_rtc_driver = {
299	.probe	 = jz4740_rtc_probe,
300	.driver	 = {
301		.name  = "jz4740-rtc",
302		.pm    = JZ4740_RTC_PM_OPS,
 
303	},
 
304};
305
306module_platform_driver(jz4740_rtc_driver);
307
308MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
309MODULE_LICENSE("GPL");
310MODULE_DESCRIPTION("RTC driver for the JZ4740 SoC\n");
311MODULE_ALIAS("platform:jz4740-rtc");
v4.17
  1/*
  2 *  Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
  3 *  Copyright (C) 2010, Paul Cercueil <paul@crapouillou.net>
  4 *	 JZ4740 SoC RTC driver
  5 *
  6 *  This program is free software; you can redistribute it and/or modify it
  7 *  under  the terms of  the GNU General Public License as published by the
  8 *  Free Software Foundation;  either version 2 of the License, or (at your
  9 *  option) any later version.
 10 *
 11 *  You should have received a copy of the GNU General Public License along
 12 *  with this program; if not, write to the Free Software Foundation, Inc.,
 13 *  675 Mass Ave, Cambridge, MA 02139, USA.
 14 *
 15 */
 16
 17#include <linux/clk.h>
 18#include <linux/io.h>
 19#include <linux/kernel.h>
 20#include <linux/module.h>
 21#include <linux/of_device.h>
 22#include <linux/platform_device.h>
 23#include <linux/reboot.h>
 24#include <linux/rtc.h>
 25#include <linux/slab.h>
 26#include <linux/spinlock.h>
 27
 28#define JZ_REG_RTC_CTRL		0x00
 29#define JZ_REG_RTC_SEC		0x04
 30#define JZ_REG_RTC_SEC_ALARM	0x08
 31#define JZ_REG_RTC_REGULATOR	0x0C
 32#define JZ_REG_RTC_HIBERNATE	0x20
 33#define JZ_REG_RTC_WAKEUP_FILTER	0x24
 34#define JZ_REG_RTC_RESET_COUNTER	0x28
 35#define JZ_REG_RTC_SCRATCHPAD	0x34
 36
 37/* The following are present on the jz4780 */
 38#define JZ_REG_RTC_WENR	0x3C
 39#define JZ_RTC_WENR_WEN	BIT(31)
 40
 41#define JZ_RTC_CTRL_WRDY	BIT(7)
 42#define JZ_RTC_CTRL_1HZ		BIT(6)
 43#define JZ_RTC_CTRL_1HZ_IRQ	BIT(5)
 44#define JZ_RTC_CTRL_AF		BIT(4)
 45#define JZ_RTC_CTRL_AF_IRQ	BIT(3)
 46#define JZ_RTC_CTRL_AE		BIT(2)
 47#define JZ_RTC_CTRL_ENABLE	BIT(0)
 48
 49/* Magic value to enable writes on jz4780 */
 50#define JZ_RTC_WENR_MAGIC	0xA55A
 51
 52#define JZ_RTC_WAKEUP_FILTER_MASK	0x0000FFE0
 53#define JZ_RTC_RESET_COUNTER_MASK	0x00000FE0
 54
 55enum jz4740_rtc_type {
 56	ID_JZ4740,
 57	ID_JZ4780,
 58};
 59
 60struct jz4740_rtc {
 61	void __iomem *base;
 62	enum jz4740_rtc_type type;
 63
 64	struct rtc_device *rtc;
 65	struct clk *clk;
 66
 67	int irq;
 68
 69	spinlock_t lock;
 70
 71	unsigned int min_wakeup_pin_assert_time;
 72	unsigned int reset_pin_assert_time;
 73};
 74
 75static struct device *dev_for_power_off;
 76
 77static inline uint32_t jz4740_rtc_reg_read(struct jz4740_rtc *rtc, size_t reg)
 78{
 79	return readl(rtc->base + reg);
 80}
 81
 82static int jz4740_rtc_wait_write_ready(struct jz4740_rtc *rtc)
 83{
 84	uint32_t ctrl;
 85	int timeout = 10000;
 86
 87	do {
 88		ctrl = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_CTRL);
 89	} while (!(ctrl & JZ_RTC_CTRL_WRDY) && --timeout);
 90
 91	return timeout ? 0 : -EIO;
 92}
 93
 94static inline int jz4780_rtc_enable_write(struct jz4740_rtc *rtc)
 95{
 96	uint32_t ctrl;
 97	int ret, timeout = 10000;
 98
 99	ret = jz4740_rtc_wait_write_ready(rtc);
100	if (ret != 0)
101		return ret;
102
103	writel(JZ_RTC_WENR_MAGIC, rtc->base + JZ_REG_RTC_WENR);
104
105	do {
106		ctrl = readl(rtc->base + JZ_REG_RTC_WENR);
107	} while (!(ctrl & JZ_RTC_WENR_WEN) && --timeout);
108
109	return timeout ? 0 : -EIO;
110}
111
112static inline int jz4740_rtc_reg_write(struct jz4740_rtc *rtc, size_t reg,
113	uint32_t val)
114{
115	int ret = 0;
116
117	if (rtc->type >= ID_JZ4780)
118		ret = jz4780_rtc_enable_write(rtc);
119	if (ret == 0)
120		ret = jz4740_rtc_wait_write_ready(rtc);
121	if (ret == 0)
122		writel(val, rtc->base + reg);
123
124	return ret;
125}
126
127static int jz4740_rtc_ctrl_set_bits(struct jz4740_rtc *rtc, uint32_t mask,
128	bool set)
129{
130	int ret;
131	unsigned long flags;
132	uint32_t ctrl;
133
134	spin_lock_irqsave(&rtc->lock, flags);
135
136	ctrl = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_CTRL);
137
138	/* Don't clear interrupt flags by accident */
139	ctrl |= JZ_RTC_CTRL_1HZ | JZ_RTC_CTRL_AF;
140
141	if (set)
142		ctrl |= mask;
143	else
144		ctrl &= ~mask;
145
146	ret = jz4740_rtc_reg_write(rtc, JZ_REG_RTC_CTRL, ctrl);
147
148	spin_unlock_irqrestore(&rtc->lock, flags);
149
150	return ret;
151}
152
153static int jz4740_rtc_read_time(struct device *dev, struct rtc_time *time)
154{
155	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
156	uint32_t secs, secs2;
157	int timeout = 5;
158
159	/* If the seconds register is read while it is updated, it can contain a
160	 * bogus value. This can be avoided by making sure that two consecutive
161	 * reads have the same value.
162	 */
163	secs = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_SEC);
164	secs2 = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_SEC);
165
166	while (secs != secs2 && --timeout) {
167		secs = secs2;
168		secs2 = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_SEC);
169	}
170
171	if (timeout == 0)
172		return -EIO;
173
174	rtc_time_to_tm(secs, time);
175
176	return 0;
177}
178
179static int jz4740_rtc_set_mmss(struct device *dev, unsigned long secs)
180{
181	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
182
183	return jz4740_rtc_reg_write(rtc, JZ_REG_RTC_SEC, secs);
184}
185
186static int jz4740_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
187{
188	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
189	uint32_t secs;
190	uint32_t ctrl;
191
192	secs = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_SEC_ALARM);
193
194	ctrl = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_CTRL);
195
196	alrm->enabled = !!(ctrl & JZ_RTC_CTRL_AE);
197	alrm->pending = !!(ctrl & JZ_RTC_CTRL_AF);
198
199	rtc_time_to_tm(secs, &alrm->time);
200
201	return rtc_valid_tm(&alrm->time);
202}
203
204static int jz4740_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
205{
206	int ret;
207	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
208	unsigned long secs;
209
210	rtc_tm_to_time(&alrm->time, &secs);
211
212	ret = jz4740_rtc_reg_write(rtc, JZ_REG_RTC_SEC_ALARM, secs);
213	if (!ret)
214		ret = jz4740_rtc_ctrl_set_bits(rtc,
215			JZ_RTC_CTRL_AE | JZ_RTC_CTRL_AF_IRQ, alrm->enabled);
216
217	return ret;
218}
219
220static int jz4740_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
221{
222	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
223	return jz4740_rtc_ctrl_set_bits(rtc, JZ_RTC_CTRL_AF_IRQ, enable);
224}
225
226static const struct rtc_class_ops jz4740_rtc_ops = {
227	.read_time	= jz4740_rtc_read_time,
228	.set_mmss	= jz4740_rtc_set_mmss,
229	.read_alarm	= jz4740_rtc_read_alarm,
230	.set_alarm	= jz4740_rtc_set_alarm,
231	.alarm_irq_enable = jz4740_rtc_alarm_irq_enable,
232};
233
234static irqreturn_t jz4740_rtc_irq(int irq, void *data)
235{
236	struct jz4740_rtc *rtc = data;
237	uint32_t ctrl;
238	unsigned long events = 0;
239
240	ctrl = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_CTRL);
241
242	if (ctrl & JZ_RTC_CTRL_1HZ)
243		events |= (RTC_UF | RTC_IRQF);
244
245	if (ctrl & JZ_RTC_CTRL_AF)
246		events |= (RTC_AF | RTC_IRQF);
247
248	rtc_update_irq(rtc->rtc, 1, events);
249
250	jz4740_rtc_ctrl_set_bits(rtc, JZ_RTC_CTRL_1HZ | JZ_RTC_CTRL_AF, false);
251
252	return IRQ_HANDLED;
253}
254
255static void jz4740_rtc_poweroff(struct device *dev)
256{
257	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
258	jz4740_rtc_reg_write(rtc, JZ_REG_RTC_HIBERNATE, 1);
259}
260
261static void jz4740_rtc_power_off(void)
262{
263	struct jz4740_rtc *rtc = dev_get_drvdata(dev_for_power_off);
264	unsigned long rtc_rate;
265	unsigned long wakeup_filter_ticks;
266	unsigned long reset_counter_ticks;
267
268	clk_prepare_enable(rtc->clk);
269
270	rtc_rate = clk_get_rate(rtc->clk);
271
272	/*
273	 * Set minimum wakeup pin assertion time: 100 ms.
274	 * Range is 0 to 2 sec if RTC is clocked at 32 kHz.
275	 */
276	wakeup_filter_ticks =
277		(rtc->min_wakeup_pin_assert_time * rtc_rate) / 1000;
278	if (wakeup_filter_ticks < JZ_RTC_WAKEUP_FILTER_MASK)
279		wakeup_filter_ticks &= JZ_RTC_WAKEUP_FILTER_MASK;
280	else
281		wakeup_filter_ticks = JZ_RTC_WAKEUP_FILTER_MASK;
282	jz4740_rtc_reg_write(rtc,
283			     JZ_REG_RTC_WAKEUP_FILTER, wakeup_filter_ticks);
284
285	/*
286	 * Set reset pin low-level assertion time after wakeup: 60 ms.
287	 * Range is 0 to 125 ms if RTC is clocked at 32 kHz.
288	 */
289	reset_counter_ticks = (rtc->reset_pin_assert_time * rtc_rate) / 1000;
290	if (reset_counter_ticks < JZ_RTC_RESET_COUNTER_MASK)
291		reset_counter_ticks &= JZ_RTC_RESET_COUNTER_MASK;
292	else
293		reset_counter_ticks = JZ_RTC_RESET_COUNTER_MASK;
294	jz4740_rtc_reg_write(rtc,
295			     JZ_REG_RTC_RESET_COUNTER, reset_counter_ticks);
296
297	jz4740_rtc_poweroff(dev_for_power_off);
298	kernel_halt();
299}
300
301static const struct of_device_id jz4740_rtc_of_match[] = {
302	{ .compatible = "ingenic,jz4740-rtc", .data = (void *)ID_JZ4740 },
303	{ .compatible = "ingenic,jz4780-rtc", .data = (void *)ID_JZ4780 },
304	{},
305};
306MODULE_DEVICE_TABLE(of, jz4740_rtc_of_match);
307
308static int jz4740_rtc_probe(struct platform_device *pdev)
309{
310	int ret;
311	struct jz4740_rtc *rtc;
312	uint32_t scratchpad;
313	struct resource *mem;
314	const struct platform_device_id *id = platform_get_device_id(pdev);
315	const struct of_device_id *of_id = of_match_device(
316			jz4740_rtc_of_match, &pdev->dev);
317	struct device_node *np = pdev->dev.of_node;
318
319	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
320	if (!rtc)
321		return -ENOMEM;
322
323	if (of_id)
324		rtc->type = (enum jz4740_rtc_type)of_id->data;
325	else
326		rtc->type = id->driver_data;
327
328	rtc->irq = platform_get_irq(pdev, 0);
329	if (rtc->irq < 0) {
330		dev_err(&pdev->dev, "Failed to get platform irq\n");
331		return -ENOENT;
332	}
333
334	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
335	rtc->base = devm_ioremap_resource(&pdev->dev, mem);
336	if (IS_ERR(rtc->base))
337		return PTR_ERR(rtc->base);
338
339	rtc->clk = devm_clk_get(&pdev->dev, "rtc");
340	if (IS_ERR(rtc->clk)) {
341		dev_err(&pdev->dev, "Failed to get RTC clock\n");
342		return PTR_ERR(rtc->clk);
343	}
344
345	spin_lock_init(&rtc->lock);
346
347	platform_set_drvdata(pdev, rtc);
348
349	device_init_wakeup(&pdev->dev, 1);
350
351	rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
352					&jz4740_rtc_ops, THIS_MODULE);
353	if (IS_ERR(rtc->rtc)) {
354		ret = PTR_ERR(rtc->rtc);
355		dev_err(&pdev->dev, "Failed to register rtc device: %d\n", ret);
356		return ret;
357	}
358
359	ret = devm_request_irq(&pdev->dev, rtc->irq, jz4740_rtc_irq, 0,
360				pdev->name, rtc);
361	if (ret) {
362		dev_err(&pdev->dev, "Failed to request rtc irq: %d\n", ret);
363		return ret;
364	}
365
366	scratchpad = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_SCRATCHPAD);
367	if (scratchpad != 0x12345678) {
368		ret = jz4740_rtc_reg_write(rtc, JZ_REG_RTC_SCRATCHPAD, 0x12345678);
369		ret = jz4740_rtc_reg_write(rtc, JZ_REG_RTC_SEC, 0);
370		if (ret) {
371			dev_err(&pdev->dev, "Could not write to RTC registers\n");
372			return ret;
373		}
374	}
375
376	if (np && of_device_is_system_power_controller(np)) {
377		if (!pm_power_off) {
378			/* Default: 60ms */
379			rtc->reset_pin_assert_time = 60;
380			of_property_read_u32(np, "reset-pin-assert-time-ms",
381					     &rtc->reset_pin_assert_time);
382
383			/* Default: 100ms */
384			rtc->min_wakeup_pin_assert_time = 100;
385			of_property_read_u32(np,
386					     "min-wakeup-pin-assert-time-ms",
387					     &rtc->min_wakeup_pin_assert_time);
388
389			dev_for_power_off = &pdev->dev;
390			pm_power_off = jz4740_rtc_power_off;
391		} else {
392			dev_warn(&pdev->dev,
393				 "Poweroff handler already present!\n");
394		}
395	}
396
397	return 0;
398}
399
400#ifdef CONFIG_PM
401static int jz4740_rtc_suspend(struct device *dev)
402{
403	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
404
405	if (device_may_wakeup(dev))
406		enable_irq_wake(rtc->irq);
407	return 0;
408}
409
410static int jz4740_rtc_resume(struct device *dev)
411{
412	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
413
414	if (device_may_wakeup(dev))
415		disable_irq_wake(rtc->irq);
416	return 0;
417}
418
419static const struct dev_pm_ops jz4740_pm_ops = {
420	.suspend = jz4740_rtc_suspend,
421	.resume  = jz4740_rtc_resume,
422};
423#define JZ4740_RTC_PM_OPS (&jz4740_pm_ops)
424
425#else
426#define JZ4740_RTC_PM_OPS NULL
427#endif  /* CONFIG_PM */
428
429static const struct platform_device_id jz4740_rtc_ids[] = {
430	{ "jz4740-rtc", ID_JZ4740 },
431	{ "jz4780-rtc", ID_JZ4780 },
432	{}
433};
434MODULE_DEVICE_TABLE(platform, jz4740_rtc_ids);
435
436static struct platform_driver jz4740_rtc_driver = {
437	.probe	 = jz4740_rtc_probe,
438	.driver	 = {
439		.name  = "jz4740-rtc",
440		.pm    = JZ4740_RTC_PM_OPS,
441		.of_match_table = of_match_ptr(jz4740_rtc_of_match),
442	},
443	.id_table = jz4740_rtc_ids,
444};
445
446module_platform_driver(jz4740_rtc_driver);
447
448MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
449MODULE_LICENSE("GPL");
450MODULE_DESCRIPTION("RTC driver for the JZ4740 SoC\n");
451MODULE_ALIAS("platform:jz4740-rtc");