Linux Audio

Check our new training course

Loading...
v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * EPSON TOYOCOM RTC-7301SF/DG Driver
  4 *
  5 * Copyright (c) 2016 Akinobu Mita <akinobu.mita@gmail.com>
  6 *
  7 * Based on rtc-rp5c01.c
  8 *
  9 * Datasheet: http://www5.epsondevice.com/en/products/parallel/rtc7301sf.html
 10 */
 11
 12#include <linux/io.h>
 13#include <linux/kernel.h>
 14#include <linux/module.h>
 15#include <linux/mod_devicetable.h>
 16#include <linux/delay.h>
 17#include <linux/regmap.h>
 18#include <linux/platform_device.h>
 19#include <linux/rtc.h>
 20
 21#define DRV_NAME "rtc-r7301"
 22
 23#define RTC7301_1_SEC		0x0	/* Bank 0 and Band 1 */
 24#define RTC7301_10_SEC		0x1	/* Bank 0 and Band 1 */
 25#define RTC7301_AE		BIT(3)
 26#define RTC7301_1_MIN		0x2	/* Bank 0 and Band 1 */
 27#define RTC7301_10_MIN		0x3	/* Bank 0 and Band 1 */
 28#define RTC7301_1_HOUR		0x4	/* Bank 0 and Band 1 */
 29#define RTC7301_10_HOUR		0x5	/* Bank 0 and Band 1 */
 30#define RTC7301_DAY_OF_WEEK	0x6	/* Bank 0 and Band 1 */
 31#define RTC7301_1_DAY		0x7	/* Bank 0 and Band 1 */
 32#define RTC7301_10_DAY		0x8	/* Bank 0 and Band 1 */
 33#define RTC7301_1_MONTH		0x9	/* Bank 0 */
 34#define RTC7301_10_MONTH	0xa	/* Bank 0 */
 35#define RTC7301_1_YEAR		0xb	/* Bank 0 */
 36#define RTC7301_10_YEAR		0xc	/* Bank 0 */
 37#define RTC7301_100_YEAR	0xd	/* Bank 0 */
 38#define RTC7301_1000_YEAR	0xe	/* Bank 0 */
 39#define RTC7301_ALARM_CONTROL	0xe	/* Bank 1 */
 40#define RTC7301_ALARM_CONTROL_AIE	BIT(0)
 41#define RTC7301_ALARM_CONTROL_AF	BIT(1)
 42#define RTC7301_TIMER_CONTROL	0xe	/* Bank 2 */
 43#define RTC7301_TIMER_CONTROL_TIE	BIT(0)
 44#define RTC7301_TIMER_CONTROL_TF	BIT(1)
 45#define RTC7301_CONTROL		0xf	/* All banks */
 46#define RTC7301_CONTROL_BUSY		BIT(0)
 47#define RTC7301_CONTROL_STOP		BIT(1)
 48#define RTC7301_CONTROL_BANK_SEL_0	BIT(2)
 49#define RTC7301_CONTROL_BANK_SEL_1	BIT(3)
 50
 51struct rtc7301_priv {
 52	struct regmap *regmap;
 53	int irq;
 54	spinlock_t lock;
 55	u8 bank;
 56};
 57
 58static const struct regmap_config rtc7301_regmap_config = {
 59	.reg_bits = 32,
 60	.val_bits = 8,
 61	.reg_stride = 4,
 62};
 63
 64static u8 rtc7301_read(struct rtc7301_priv *priv, unsigned int reg)
 65{
 66	int reg_stride = regmap_get_reg_stride(priv->regmap);
 67	unsigned int val;
 68
 69	regmap_read(priv->regmap, reg_stride * reg, &val);
 70
 71	return val & 0xf;
 72}
 73
 74static void rtc7301_write(struct rtc7301_priv *priv, u8 val, unsigned int reg)
 75{
 76	int reg_stride = regmap_get_reg_stride(priv->regmap);
 77
 78	regmap_write(priv->regmap, reg_stride * reg, val);
 79}
 80
 81static void rtc7301_update_bits(struct rtc7301_priv *priv, unsigned int reg,
 82				u8 mask, u8 val)
 83{
 84	int reg_stride = regmap_get_reg_stride(priv->regmap);
 85
 86	regmap_update_bits(priv->regmap, reg_stride * reg, mask, val);
 87}
 88
 89static int rtc7301_wait_while_busy(struct rtc7301_priv *priv)
 90{
 91	int retries = 100;
 92
 93	while (retries-- > 0) {
 94		u8 val;
 95
 96		val = rtc7301_read(priv, RTC7301_CONTROL);
 97		if (!(val & RTC7301_CONTROL_BUSY))
 98			return 0;
 99
100		udelay(300);
101	}
102
103	return -ETIMEDOUT;
104}
105
106static void rtc7301_stop(struct rtc7301_priv *priv)
107{
108	rtc7301_update_bits(priv, RTC7301_CONTROL, RTC7301_CONTROL_STOP,
109			    RTC7301_CONTROL_STOP);
110}
111
112static void rtc7301_start(struct rtc7301_priv *priv)
113{
114	rtc7301_update_bits(priv, RTC7301_CONTROL, RTC7301_CONTROL_STOP, 0);
115}
116
117static void rtc7301_select_bank(struct rtc7301_priv *priv, u8 bank)
118{
119	u8 val = 0;
120
121	if (bank == priv->bank)
122		return;
123
124	if (bank & BIT(0))
125		val |= RTC7301_CONTROL_BANK_SEL_0;
126	if (bank & BIT(1))
127		val |= RTC7301_CONTROL_BANK_SEL_1;
128
129	rtc7301_update_bits(priv, RTC7301_CONTROL,
130			    RTC7301_CONTROL_BANK_SEL_0 |
131			    RTC7301_CONTROL_BANK_SEL_1, val);
132
133	priv->bank = bank;
134}
135
136static void rtc7301_get_time(struct rtc7301_priv *priv, struct rtc_time *tm,
137			     bool alarm)
138{
139	int year;
140
141	tm->tm_sec = rtc7301_read(priv, RTC7301_1_SEC);
142	tm->tm_sec += (rtc7301_read(priv, RTC7301_10_SEC) & ~RTC7301_AE) * 10;
143	tm->tm_min = rtc7301_read(priv, RTC7301_1_MIN);
144	tm->tm_min += (rtc7301_read(priv, RTC7301_10_MIN) & ~RTC7301_AE) * 10;
145	tm->tm_hour = rtc7301_read(priv, RTC7301_1_HOUR);
146	tm->tm_hour += (rtc7301_read(priv, RTC7301_10_HOUR) & ~RTC7301_AE) * 10;
147	tm->tm_mday = rtc7301_read(priv, RTC7301_1_DAY);
148	tm->tm_mday += (rtc7301_read(priv, RTC7301_10_DAY) & ~RTC7301_AE) * 10;
149
150	if (alarm) {
151		tm->tm_wday = -1;
152		tm->tm_mon = -1;
153		tm->tm_year = -1;
154		tm->tm_yday = -1;
155		tm->tm_isdst = -1;
156		return;
157	}
158
159	tm->tm_wday = (rtc7301_read(priv, RTC7301_DAY_OF_WEEK) & ~RTC7301_AE);
160	tm->tm_mon = rtc7301_read(priv, RTC7301_10_MONTH) * 10 +
161		     rtc7301_read(priv, RTC7301_1_MONTH) - 1;
162	year = rtc7301_read(priv, RTC7301_1000_YEAR) * 1000 +
163	       rtc7301_read(priv, RTC7301_100_YEAR) * 100 +
164	       rtc7301_read(priv, RTC7301_10_YEAR) * 10 +
165	       rtc7301_read(priv, RTC7301_1_YEAR);
166
167	tm->tm_year = year - 1900;
168}
169
170static void rtc7301_write_time(struct rtc7301_priv *priv, struct rtc_time *tm,
171			       bool alarm)
172{
173	int year;
174
175	rtc7301_write(priv, tm->tm_sec % 10, RTC7301_1_SEC);
176	rtc7301_write(priv, tm->tm_sec / 10, RTC7301_10_SEC);
177
178	rtc7301_write(priv, tm->tm_min % 10, RTC7301_1_MIN);
179	rtc7301_write(priv, tm->tm_min / 10, RTC7301_10_MIN);
180
181	rtc7301_write(priv, tm->tm_hour % 10, RTC7301_1_HOUR);
182	rtc7301_write(priv, tm->tm_hour / 10, RTC7301_10_HOUR);
183
184	rtc7301_write(priv, tm->tm_mday % 10, RTC7301_1_DAY);
185	rtc7301_write(priv, tm->tm_mday / 10, RTC7301_10_DAY);
186
187	/* Don't care for alarm register */
188	rtc7301_write(priv, alarm ? RTC7301_AE : tm->tm_wday,
189		      RTC7301_DAY_OF_WEEK);
190
191	if (alarm)
192		return;
193
194	rtc7301_write(priv, (tm->tm_mon + 1) % 10, RTC7301_1_MONTH);
195	rtc7301_write(priv, (tm->tm_mon + 1) / 10, RTC7301_10_MONTH);
196
197	year = tm->tm_year + 1900;
198
199	rtc7301_write(priv, year % 10, RTC7301_1_YEAR);
200	rtc7301_write(priv, (year / 10) % 10, RTC7301_10_YEAR);
201	rtc7301_write(priv, (year / 100) % 10, RTC7301_100_YEAR);
202	rtc7301_write(priv, year / 1000, RTC7301_1000_YEAR);
203}
204
205static void rtc7301_alarm_irq(struct rtc7301_priv *priv, unsigned int enabled)
206{
207	rtc7301_update_bits(priv, RTC7301_ALARM_CONTROL,
208			    RTC7301_ALARM_CONTROL_AF |
209			    RTC7301_ALARM_CONTROL_AIE,
210			    enabled ? RTC7301_ALARM_CONTROL_AIE : 0);
211}
212
213static int rtc7301_read_time(struct device *dev, struct rtc_time *tm)
214{
215	struct rtc7301_priv *priv = dev_get_drvdata(dev);
216	unsigned long flags;
217	int err;
218
219	spin_lock_irqsave(&priv->lock, flags);
220
221	rtc7301_select_bank(priv, 0);
222
223	err = rtc7301_wait_while_busy(priv);
224	if (!err)
225		rtc7301_get_time(priv, tm, false);
226
227	spin_unlock_irqrestore(&priv->lock, flags);
228
229	return err;
230}
231
232static int rtc7301_set_time(struct device *dev, struct rtc_time *tm)
233{
234	struct rtc7301_priv *priv = dev_get_drvdata(dev);
235	unsigned long flags;
236
237	spin_lock_irqsave(&priv->lock, flags);
238
239	rtc7301_stop(priv);
240	udelay(300);
241	rtc7301_select_bank(priv, 0);
242	rtc7301_write_time(priv, tm, false);
243	rtc7301_start(priv);
244
245	spin_unlock_irqrestore(&priv->lock, flags);
246
247	return 0;
248}
249
250static int rtc7301_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
251{
252	struct rtc7301_priv *priv = dev_get_drvdata(dev);
253	unsigned long flags;
254	u8 alrm_ctrl;
255
256	if (priv->irq <= 0)
257		return -EINVAL;
258
259	spin_lock_irqsave(&priv->lock, flags);
260
261	rtc7301_select_bank(priv, 1);
262	rtc7301_get_time(priv, &alarm->time, true);
263
264	alrm_ctrl = rtc7301_read(priv, RTC7301_ALARM_CONTROL);
265
266	alarm->enabled = !!(alrm_ctrl & RTC7301_ALARM_CONTROL_AIE);
267	alarm->pending = !!(alrm_ctrl & RTC7301_ALARM_CONTROL_AF);
268
269	spin_unlock_irqrestore(&priv->lock, flags);
270
271	return 0;
272}
273
274static int rtc7301_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
275{
276	struct rtc7301_priv *priv = dev_get_drvdata(dev);
277	unsigned long flags;
278
279	if (priv->irq <= 0)
280		return -EINVAL;
281
282	spin_lock_irqsave(&priv->lock, flags);
283
284	rtc7301_select_bank(priv, 1);
285	rtc7301_write_time(priv, &alarm->time, true);
286	rtc7301_alarm_irq(priv, alarm->enabled);
287
288	spin_unlock_irqrestore(&priv->lock, flags);
289
290	return 0;
291}
292
293static int rtc7301_alarm_irq_enable(struct device *dev, unsigned int enabled)
294{
295	struct rtc7301_priv *priv = dev_get_drvdata(dev);
296	unsigned long flags;
297
298	if (priv->irq <= 0)
299		return -EINVAL;
300
301	spin_lock_irqsave(&priv->lock, flags);
302
303	rtc7301_select_bank(priv, 1);
304	rtc7301_alarm_irq(priv, enabled);
305
306	spin_unlock_irqrestore(&priv->lock, flags);
307
308	return 0;
309}
310
311static const struct rtc_class_ops rtc7301_rtc_ops = {
312	.read_time	= rtc7301_read_time,
313	.set_time	= rtc7301_set_time,
314	.read_alarm	= rtc7301_read_alarm,
315	.set_alarm	= rtc7301_set_alarm,
316	.alarm_irq_enable = rtc7301_alarm_irq_enable,
317};
318
319static irqreturn_t rtc7301_irq_handler(int irq, void *dev_id)
320{
321	struct rtc_device *rtc = dev_id;
322	struct rtc7301_priv *priv = dev_get_drvdata(rtc->dev.parent);
 
323	irqreturn_t ret = IRQ_NONE;
324	u8 alrm_ctrl;
325
326	spin_lock(&priv->lock);
327
328	rtc7301_select_bank(priv, 1);
329
330	alrm_ctrl = rtc7301_read(priv, RTC7301_ALARM_CONTROL);
331	if (alrm_ctrl & RTC7301_ALARM_CONTROL_AF) {
332		ret = IRQ_HANDLED;
333		rtc7301_alarm_irq(priv, false);
334		rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF);
335	}
336
337	spin_unlock(&priv->lock);
338
339	return ret;
340}
341
342static void rtc7301_init(struct rtc7301_priv *priv)
343{
344	unsigned long flags;
345
346	spin_lock_irqsave(&priv->lock, flags);
347
348	rtc7301_select_bank(priv, 2);
349	rtc7301_write(priv, 0, RTC7301_TIMER_CONTROL);
350
351	spin_unlock_irqrestore(&priv->lock, flags);
352}
353
354static int __init rtc7301_rtc_probe(struct platform_device *dev)
355{
 
356	void __iomem *regs;
357	struct rtc7301_priv *priv;
358	struct rtc_device *rtc;
359	int ret;
360
 
 
 
 
361	priv = devm_kzalloc(&dev->dev, sizeof(*priv), GFP_KERNEL);
362	if (!priv)
363		return -ENOMEM;
364
365	regs = devm_platform_ioremap_resource(dev, 0);
366	if (IS_ERR(regs))
367		return PTR_ERR(regs);
368
369	priv->regmap = devm_regmap_init_mmio(&dev->dev, regs,
370					     &rtc7301_regmap_config);
371	if (IS_ERR(priv->regmap))
372		return PTR_ERR(priv->regmap);
373
374	priv->irq = platform_get_irq(dev, 0);
375
376	spin_lock_init(&priv->lock);
377	priv->bank = -1;
378
379	rtc7301_init(priv);
380
381	platform_set_drvdata(dev, priv);
382
383	rtc = devm_rtc_device_register(&dev->dev, DRV_NAME, &rtc7301_rtc_ops,
384				       THIS_MODULE);
385	if (IS_ERR(rtc))
386		return PTR_ERR(rtc);
387
388	if (priv->irq > 0) {
389		ret = devm_request_irq(&dev->dev, priv->irq,
390				       rtc7301_irq_handler, IRQF_SHARED,
391				       dev_name(&dev->dev), rtc);
392		if (ret) {
393			priv->irq = 0;
394			dev_err(&dev->dev, "unable to request IRQ\n");
395		} else {
396			device_set_wakeup_capable(&dev->dev, true);
397		}
398	}
399
400	return 0;
401}
402
403#ifdef CONFIG_PM_SLEEP
404
405static int rtc7301_suspend(struct device *dev)
406{
407	struct rtc7301_priv *priv = dev_get_drvdata(dev);
408
409	if (device_may_wakeup(dev))
410		enable_irq_wake(priv->irq);
411
412	return 0;
413}
414
415static int rtc7301_resume(struct device *dev)
416{
417	struct rtc7301_priv *priv = dev_get_drvdata(dev);
418
419	if (device_may_wakeup(dev))
420		disable_irq_wake(priv->irq);
421
422	return 0;
423}
424
425#endif
426
427static SIMPLE_DEV_PM_OPS(rtc7301_pm_ops, rtc7301_suspend, rtc7301_resume);
428
429static const struct of_device_id rtc7301_dt_match[] = {
430	{ .compatible = "epson,rtc7301sf" },
431	{ .compatible = "epson,rtc7301dg" },
432	{}
433};
434MODULE_DEVICE_TABLE(of, rtc7301_dt_match);
435
436static struct platform_driver rtc7301_rtc_driver = {
437	.driver	= {
438		.name = DRV_NAME,
439		.of_match_table = rtc7301_dt_match,
440		.pm = &rtc7301_pm_ops,
441	},
442};
443
444module_platform_driver_probe(rtc7301_rtc_driver, rtc7301_rtc_probe);
445
446MODULE_AUTHOR("Akinobu Mita <akinobu.mita@gmail.com>");
447MODULE_LICENSE("GPL");
448MODULE_DESCRIPTION("EPSON TOYOCOM RTC-7301SF/DG Driver");
449MODULE_ALIAS("platform:rtc-r7301");
v4.17
 
  1/*
  2 * EPSON TOYOCOM RTC-7301SF/DG Driver
  3 *
  4 * Copyright (c) 2016 Akinobu Mita <akinobu.mita@gmail.com>
  5 *
  6 * Based on rtc-rp5c01.c
  7 *
  8 * Datasheet: http://www5.epsondevice.com/en/products/parallel/rtc7301sf.html
  9 */
 10
 11#include <linux/io.h>
 12#include <linux/kernel.h>
 13#include <linux/module.h>
 
 14#include <linux/delay.h>
 15#include <linux/regmap.h>
 16#include <linux/platform_device.h>
 17#include <linux/rtc.h>
 18
 19#define DRV_NAME "rtc-r7301"
 20
 21#define RTC7301_1_SEC		0x0	/* Bank 0 and Band 1 */
 22#define RTC7301_10_SEC		0x1	/* Bank 0 and Band 1 */
 23#define RTC7301_AE		BIT(3)
 24#define RTC7301_1_MIN		0x2	/* Bank 0 and Band 1 */
 25#define RTC7301_10_MIN		0x3	/* Bank 0 and Band 1 */
 26#define RTC7301_1_HOUR		0x4	/* Bank 0 and Band 1 */
 27#define RTC7301_10_HOUR		0x5	/* Bank 0 and Band 1 */
 28#define RTC7301_DAY_OF_WEEK	0x6	/* Bank 0 and Band 1 */
 29#define RTC7301_1_DAY		0x7	/* Bank 0 and Band 1 */
 30#define RTC7301_10_DAY		0x8	/* Bank 0 and Band 1 */
 31#define RTC7301_1_MONTH		0x9	/* Bank 0 */
 32#define RTC7301_10_MONTH	0xa	/* Bank 0 */
 33#define RTC7301_1_YEAR		0xb	/* Bank 0 */
 34#define RTC7301_10_YEAR		0xc	/* Bank 0 */
 35#define RTC7301_100_YEAR	0xd	/* Bank 0 */
 36#define RTC7301_1000_YEAR	0xe	/* Bank 0 */
 37#define RTC7301_ALARM_CONTROL	0xe	/* Bank 1 */
 38#define RTC7301_ALARM_CONTROL_AIE	BIT(0)
 39#define RTC7301_ALARM_CONTROL_AF	BIT(1)
 40#define RTC7301_TIMER_CONTROL	0xe	/* Bank 2 */
 41#define RTC7301_TIMER_CONTROL_TIE	BIT(0)
 42#define RTC7301_TIMER_CONTROL_TF	BIT(1)
 43#define RTC7301_CONTROL		0xf	/* All banks */
 44#define RTC7301_CONTROL_BUSY		BIT(0)
 45#define RTC7301_CONTROL_STOP		BIT(1)
 46#define RTC7301_CONTROL_BANK_SEL_0	BIT(2)
 47#define RTC7301_CONTROL_BANK_SEL_1	BIT(3)
 48
 49struct rtc7301_priv {
 50	struct regmap *regmap;
 51	int irq;
 52	spinlock_t lock;
 53	u8 bank;
 54};
 55
 56static const struct regmap_config rtc7301_regmap_config = {
 57	.reg_bits = 32,
 58	.val_bits = 8,
 59	.reg_stride = 4,
 60};
 61
 62static u8 rtc7301_read(struct rtc7301_priv *priv, unsigned int reg)
 63{
 64	int reg_stride = regmap_get_reg_stride(priv->regmap);
 65	unsigned int val;
 66
 67	regmap_read(priv->regmap, reg_stride * reg, &val);
 68
 69	return val & 0xf;
 70}
 71
 72static void rtc7301_write(struct rtc7301_priv *priv, u8 val, unsigned int reg)
 73{
 74	int reg_stride = regmap_get_reg_stride(priv->regmap);
 75
 76	regmap_write(priv->regmap, reg_stride * reg, val);
 77}
 78
 79static void rtc7301_update_bits(struct rtc7301_priv *priv, unsigned int reg,
 80				u8 mask, u8 val)
 81{
 82	int reg_stride = regmap_get_reg_stride(priv->regmap);
 83
 84	regmap_update_bits(priv->regmap, reg_stride * reg, mask, val);
 85}
 86
 87static int rtc7301_wait_while_busy(struct rtc7301_priv *priv)
 88{
 89	int retries = 100;
 90
 91	while (retries-- > 0) {
 92		u8 val;
 93
 94		val = rtc7301_read(priv, RTC7301_CONTROL);
 95		if (!(val & RTC7301_CONTROL_BUSY))
 96			return 0;
 97
 98		udelay(300);
 99	}
100
101	return -ETIMEDOUT;
102}
103
104static void rtc7301_stop(struct rtc7301_priv *priv)
105{
106	rtc7301_update_bits(priv, RTC7301_CONTROL, RTC7301_CONTROL_STOP,
107			    RTC7301_CONTROL_STOP);
108}
109
110static void rtc7301_start(struct rtc7301_priv *priv)
111{
112	rtc7301_update_bits(priv, RTC7301_CONTROL, RTC7301_CONTROL_STOP, 0);
113}
114
115static void rtc7301_select_bank(struct rtc7301_priv *priv, u8 bank)
116{
117	u8 val = 0;
118
119	if (bank == priv->bank)
120		return;
121
122	if (bank & BIT(0))
123		val |= RTC7301_CONTROL_BANK_SEL_0;
124	if (bank & BIT(1))
125		val |= RTC7301_CONTROL_BANK_SEL_1;
126
127	rtc7301_update_bits(priv, RTC7301_CONTROL,
128			    RTC7301_CONTROL_BANK_SEL_0 |
129			    RTC7301_CONTROL_BANK_SEL_1, val);
130
131	priv->bank = bank;
132}
133
134static void rtc7301_get_time(struct rtc7301_priv *priv, struct rtc_time *tm,
135			     bool alarm)
136{
137	int year;
138
139	tm->tm_sec = rtc7301_read(priv, RTC7301_1_SEC);
140	tm->tm_sec += (rtc7301_read(priv, RTC7301_10_SEC) & ~RTC7301_AE) * 10;
141	tm->tm_min = rtc7301_read(priv, RTC7301_1_MIN);
142	tm->tm_min += (rtc7301_read(priv, RTC7301_10_MIN) & ~RTC7301_AE) * 10;
143	tm->tm_hour = rtc7301_read(priv, RTC7301_1_HOUR);
144	tm->tm_hour += (rtc7301_read(priv, RTC7301_10_HOUR) & ~RTC7301_AE) * 10;
145	tm->tm_mday = rtc7301_read(priv, RTC7301_1_DAY);
146	tm->tm_mday += (rtc7301_read(priv, RTC7301_10_DAY) & ~RTC7301_AE) * 10;
147
148	if (alarm) {
149		tm->tm_wday = -1;
150		tm->tm_mon = -1;
151		tm->tm_year = -1;
152		tm->tm_yday = -1;
153		tm->tm_isdst = -1;
154		return;
155	}
156
157	tm->tm_wday = (rtc7301_read(priv, RTC7301_DAY_OF_WEEK) & ~RTC7301_AE);
158	tm->tm_mon = rtc7301_read(priv, RTC7301_10_MONTH) * 10 +
159		     rtc7301_read(priv, RTC7301_1_MONTH) - 1;
160	year = rtc7301_read(priv, RTC7301_1000_YEAR) * 1000 +
161	       rtc7301_read(priv, RTC7301_100_YEAR) * 100 +
162	       rtc7301_read(priv, RTC7301_10_YEAR) * 10 +
163	       rtc7301_read(priv, RTC7301_1_YEAR);
164
165	tm->tm_year = year - 1900;
166}
167
168static void rtc7301_write_time(struct rtc7301_priv *priv, struct rtc_time *tm,
169			       bool alarm)
170{
171	int year;
172
173	rtc7301_write(priv, tm->tm_sec % 10, RTC7301_1_SEC);
174	rtc7301_write(priv, tm->tm_sec / 10, RTC7301_10_SEC);
175
176	rtc7301_write(priv, tm->tm_min % 10, RTC7301_1_MIN);
177	rtc7301_write(priv, tm->tm_min / 10, RTC7301_10_MIN);
178
179	rtc7301_write(priv, tm->tm_hour % 10, RTC7301_1_HOUR);
180	rtc7301_write(priv, tm->tm_hour / 10, RTC7301_10_HOUR);
181
182	rtc7301_write(priv, tm->tm_mday % 10, RTC7301_1_DAY);
183	rtc7301_write(priv, tm->tm_mday / 10, RTC7301_10_DAY);
184
185	/* Don't care for alarm register */
186	rtc7301_write(priv, alarm ? RTC7301_AE : tm->tm_wday,
187		      RTC7301_DAY_OF_WEEK);
188
189	if (alarm)
190		return;
191
192	rtc7301_write(priv, (tm->tm_mon + 1) % 10, RTC7301_1_MONTH);
193	rtc7301_write(priv, (tm->tm_mon + 1) / 10, RTC7301_10_MONTH);
194
195	year = tm->tm_year + 1900;
196
197	rtc7301_write(priv, year % 10, RTC7301_1_YEAR);
198	rtc7301_write(priv, (year / 10) % 10, RTC7301_10_YEAR);
199	rtc7301_write(priv, (year / 100) % 10, RTC7301_100_YEAR);
200	rtc7301_write(priv, year / 1000, RTC7301_1000_YEAR);
201}
202
203static void rtc7301_alarm_irq(struct rtc7301_priv *priv, unsigned int enabled)
204{
205	rtc7301_update_bits(priv, RTC7301_ALARM_CONTROL,
206			    RTC7301_ALARM_CONTROL_AF |
207			    RTC7301_ALARM_CONTROL_AIE,
208			    enabled ? RTC7301_ALARM_CONTROL_AIE : 0);
209}
210
211static int rtc7301_read_time(struct device *dev, struct rtc_time *tm)
212{
213	struct rtc7301_priv *priv = dev_get_drvdata(dev);
214	unsigned long flags;
215	int err;
216
217	spin_lock_irqsave(&priv->lock, flags);
218
219	rtc7301_select_bank(priv, 0);
220
221	err = rtc7301_wait_while_busy(priv);
222	if (!err)
223		rtc7301_get_time(priv, tm, false);
224
225	spin_unlock_irqrestore(&priv->lock, flags);
226
227	return err;
228}
229
230static int rtc7301_set_time(struct device *dev, struct rtc_time *tm)
231{
232	struct rtc7301_priv *priv = dev_get_drvdata(dev);
233	unsigned long flags;
234
235	spin_lock_irqsave(&priv->lock, flags);
236
237	rtc7301_stop(priv);
238	udelay(300);
239	rtc7301_select_bank(priv, 0);
240	rtc7301_write_time(priv, tm, false);
241	rtc7301_start(priv);
242
243	spin_unlock_irqrestore(&priv->lock, flags);
244
245	return 0;
246}
247
248static int rtc7301_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
249{
250	struct rtc7301_priv *priv = dev_get_drvdata(dev);
251	unsigned long flags;
252	u8 alrm_ctrl;
253
254	if (priv->irq <= 0)
255		return -EINVAL;
256
257	spin_lock_irqsave(&priv->lock, flags);
258
259	rtc7301_select_bank(priv, 1);
260	rtc7301_get_time(priv, &alarm->time, true);
261
262	alrm_ctrl = rtc7301_read(priv, RTC7301_ALARM_CONTROL);
263
264	alarm->enabled = !!(alrm_ctrl & RTC7301_ALARM_CONTROL_AIE);
265	alarm->pending = !!(alrm_ctrl & RTC7301_ALARM_CONTROL_AF);
266
267	spin_unlock_irqrestore(&priv->lock, flags);
268
269	return 0;
270}
271
272static int rtc7301_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
273{
274	struct rtc7301_priv *priv = dev_get_drvdata(dev);
275	unsigned long flags;
276
277	if (priv->irq <= 0)
278		return -EINVAL;
279
280	spin_lock_irqsave(&priv->lock, flags);
281
282	rtc7301_select_bank(priv, 1);
283	rtc7301_write_time(priv, &alarm->time, true);
284	rtc7301_alarm_irq(priv, alarm->enabled);
285
286	spin_unlock_irqrestore(&priv->lock, flags);
287
288	return 0;
289}
290
291static int rtc7301_alarm_irq_enable(struct device *dev, unsigned int enabled)
292{
293	struct rtc7301_priv *priv = dev_get_drvdata(dev);
294	unsigned long flags;
295
296	if (priv->irq <= 0)
297		return -EINVAL;
298
299	spin_lock_irqsave(&priv->lock, flags);
300
301	rtc7301_select_bank(priv, 1);
302	rtc7301_alarm_irq(priv, enabled);
303
304	spin_unlock_irqrestore(&priv->lock, flags);
305
306	return 0;
307}
308
309static const struct rtc_class_ops rtc7301_rtc_ops = {
310	.read_time	= rtc7301_read_time,
311	.set_time	= rtc7301_set_time,
312	.read_alarm	= rtc7301_read_alarm,
313	.set_alarm	= rtc7301_set_alarm,
314	.alarm_irq_enable = rtc7301_alarm_irq_enable,
315};
316
317static irqreturn_t rtc7301_irq_handler(int irq, void *dev_id)
318{
319	struct rtc_device *rtc = dev_id;
320	struct rtc7301_priv *priv = dev_get_drvdata(rtc->dev.parent);
321	unsigned long flags;
322	irqreturn_t ret = IRQ_NONE;
323	u8 alrm_ctrl;
324
325	spin_lock_irqsave(&priv->lock, flags);
326
327	rtc7301_select_bank(priv, 1);
328
329	alrm_ctrl = rtc7301_read(priv, RTC7301_ALARM_CONTROL);
330	if (alrm_ctrl & RTC7301_ALARM_CONTROL_AF) {
331		ret = IRQ_HANDLED;
332		rtc7301_alarm_irq(priv, false);
333		rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF);
334	}
335
336	spin_unlock_irqrestore(&priv->lock, flags);
337
338	return ret;
339}
340
341static void rtc7301_init(struct rtc7301_priv *priv)
342{
343	unsigned long flags;
344
345	spin_lock_irqsave(&priv->lock, flags);
346
347	rtc7301_select_bank(priv, 2);
348	rtc7301_write(priv, 0, RTC7301_TIMER_CONTROL);
349
350	spin_unlock_irqrestore(&priv->lock, flags);
351}
352
353static int __init rtc7301_rtc_probe(struct platform_device *dev)
354{
355	struct resource *res;
356	void __iomem *regs;
357	struct rtc7301_priv *priv;
358	struct rtc_device *rtc;
359	int ret;
360
361	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
362	if (!res)
363		return -ENODEV;
364
365	priv = devm_kzalloc(&dev->dev, sizeof(*priv), GFP_KERNEL);
366	if (!priv)
367		return -ENOMEM;
368
369	regs = devm_ioremap_resource(&dev->dev, res);
370	if (IS_ERR(regs))
371		return PTR_ERR(regs);
372
373	priv->regmap = devm_regmap_init_mmio(&dev->dev, regs,
374					     &rtc7301_regmap_config);
375	if (IS_ERR(priv->regmap))
376		return PTR_ERR(priv->regmap);
377
378	priv->irq = platform_get_irq(dev, 0);
379
380	spin_lock_init(&priv->lock);
381	priv->bank = -1;
382
383	rtc7301_init(priv);
384
385	platform_set_drvdata(dev, priv);
386
387	rtc = devm_rtc_device_register(&dev->dev, DRV_NAME, &rtc7301_rtc_ops,
388				       THIS_MODULE);
389	if (IS_ERR(rtc))
390		return PTR_ERR(rtc);
391
392	if (priv->irq > 0) {
393		ret = devm_request_irq(&dev->dev, priv->irq,
394				       rtc7301_irq_handler, IRQF_SHARED,
395				       dev_name(&dev->dev), rtc);
396		if (ret) {
397			priv->irq = 0;
398			dev_err(&dev->dev, "unable to request IRQ\n");
399		} else {
400			device_set_wakeup_capable(&dev->dev, true);
401		}
402	}
403
404	return 0;
405}
406
407#ifdef CONFIG_PM_SLEEP
408
409static int rtc7301_suspend(struct device *dev)
410{
411	struct rtc7301_priv *priv = dev_get_drvdata(dev);
412
413	if (device_may_wakeup(dev))
414		enable_irq_wake(priv->irq);
415
416	return 0;
417}
418
419static int rtc7301_resume(struct device *dev)
420{
421	struct rtc7301_priv *priv = dev_get_drvdata(dev);
422
423	if (device_may_wakeup(dev))
424		disable_irq_wake(priv->irq);
425
426	return 0;
427}
428
429#endif
430
431static SIMPLE_DEV_PM_OPS(rtc7301_pm_ops, rtc7301_suspend, rtc7301_resume);
432
433static const struct of_device_id rtc7301_dt_match[] = {
434	{ .compatible = "epson,rtc7301sf" },
435	{ .compatible = "epson,rtc7301dg" },
436	{}
437};
438MODULE_DEVICE_TABLE(of, rtc7301_dt_match);
439
440static struct platform_driver rtc7301_rtc_driver = {
441	.driver	= {
442		.name = DRV_NAME,
443		.of_match_table = rtc7301_dt_match,
444		.pm = &rtc7301_pm_ops,
445	},
446};
447
448module_platform_driver_probe(rtc7301_rtc_driver, rtc7301_rtc_probe);
449
450MODULE_AUTHOR("Akinobu Mita <akinobu.mita@gmail.com>");
451MODULE_LICENSE("GPL");
452MODULE_DESCRIPTION("EPSON TOYOCOM RTC-7301SF/DG Driver");
453MODULE_ALIAS("platform:rtc-r7301");