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1/*
2 * Real Time Clock interface for Linux on Atmel AT91RM9200
3 *
4 * Copyright (C) 2002 Rick Bronson
5 *
6 * Converted to RTC class model by Andrew Victor
7 *
8 * Ported to Linux 2.6 by Steven Scholz
9 * Based on s3c2410-rtc.c Simtec Electronics
10 *
11 * Based on sa1100-rtc.c by Nils Faerber
12 * Based on rtc.c by Paul Gortmaker
13 *
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public License
16 * as published by the Free Software Foundation; either version
17 * 2 of the License, or (at your option) any later version.
18 *
19 */
20
21#include <linux/module.h>
22#include <linux/kernel.h>
23#include <linux/platform_device.h>
24#include <linux/time.h>
25#include <linux/rtc.h>
26#include <linux/bcd.h>
27#include <linux/interrupt.h>
28#include <linux/ioctl.h>
29#include <linux/completion.h>
30
31#include <asm/uaccess.h>
32
33#include <mach/at91_rtc.h>
34
35#define at91_rtc_read(field) \
36 __raw_readl(at91_rtc_regs + field)
37#define at91_rtc_write(field, val) \
38 __raw_writel((val), at91_rtc_regs + field)
39
40#define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */
41
42static DECLARE_COMPLETION(at91_rtc_updated);
43static unsigned int at91_alarm_year = AT91_RTC_EPOCH;
44static void __iomem *at91_rtc_regs;
45static int irq;
46
47/*
48 * Decode time/date into rtc_time structure
49 */
50static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg,
51 struct rtc_time *tm)
52{
53 unsigned int time, date;
54
55 /* must read twice in case it changes */
56 do {
57 time = at91_rtc_read(timereg);
58 date = at91_rtc_read(calreg);
59 } while ((time != at91_rtc_read(timereg)) ||
60 (date != at91_rtc_read(calreg)));
61
62 tm->tm_sec = bcd2bin((time & AT91_RTC_SEC) >> 0);
63 tm->tm_min = bcd2bin((time & AT91_RTC_MIN) >> 8);
64 tm->tm_hour = bcd2bin((time & AT91_RTC_HOUR) >> 16);
65
66 /*
67 * The Calendar Alarm register does not have a field for
68 * the year - so these will return an invalid value. When an
69 * alarm is set, at91_alarm_year will store the current year.
70 */
71 tm->tm_year = bcd2bin(date & AT91_RTC_CENT) * 100; /* century */
72 tm->tm_year += bcd2bin((date & AT91_RTC_YEAR) >> 8); /* year */
73
74 tm->tm_wday = bcd2bin((date & AT91_RTC_DAY) >> 21) - 1; /* day of the week [0-6], Sunday=0 */
75 tm->tm_mon = bcd2bin((date & AT91_RTC_MONTH) >> 16) - 1;
76 tm->tm_mday = bcd2bin((date & AT91_RTC_DATE) >> 24);
77}
78
79/*
80 * Read current time and date in RTC
81 */
82static int at91_rtc_readtime(struct device *dev, struct rtc_time *tm)
83{
84 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm);
85 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
86 tm->tm_year = tm->tm_year - 1900;
87
88 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
89 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
90 tm->tm_hour, tm->tm_min, tm->tm_sec);
91
92 return 0;
93}
94
95/*
96 * Set current time and date in RTC
97 */
98static int at91_rtc_settime(struct device *dev, struct rtc_time *tm)
99{
100 unsigned long cr;
101
102 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
103 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
104 tm->tm_hour, tm->tm_min, tm->tm_sec);
105
106 /* Stop Time/Calendar from counting */
107 cr = at91_rtc_read(AT91_RTC_CR);
108 at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM);
109
110 at91_rtc_write(AT91_RTC_IER, AT91_RTC_ACKUPD);
111 wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
112 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD);
113
114 at91_rtc_write(AT91_RTC_TIMR,
115 bin2bcd(tm->tm_sec) << 0
116 | bin2bcd(tm->tm_min) << 8
117 | bin2bcd(tm->tm_hour) << 16);
118
119 at91_rtc_write(AT91_RTC_CALR,
120 bin2bcd((tm->tm_year + 1900) / 100) /* century */
121 | bin2bcd(tm->tm_year % 100) << 8 /* year */
122 | bin2bcd(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */
123 | bin2bcd(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */
124 | bin2bcd(tm->tm_mday) << 24);
125
126 /* Restart Time/Calendar */
127 cr = at91_rtc_read(AT91_RTC_CR);
128 at91_rtc_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM));
129
130 return 0;
131}
132
133/*
134 * Read alarm time and date in RTC
135 */
136static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
137{
138 struct rtc_time *tm = &alrm->time;
139
140 at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm);
141 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
142 tm->tm_year = at91_alarm_year - 1900;
143
144 alrm->enabled = (at91_rtc_read(AT91_RTC_IMR) & AT91_RTC_ALARM)
145 ? 1 : 0;
146
147 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
148 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
149 tm->tm_hour, tm->tm_min, tm->tm_sec);
150
151 return 0;
152}
153
154/*
155 * Set alarm time and date in RTC
156 */
157static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
158{
159 struct rtc_time tm;
160
161 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm);
162
163 at91_alarm_year = tm.tm_year;
164
165 tm.tm_hour = alrm->time.tm_hour;
166 tm.tm_min = alrm->time.tm_min;
167 tm.tm_sec = alrm->time.tm_sec;
168
169 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM);
170 at91_rtc_write(AT91_RTC_TIMALR,
171 bin2bcd(tm.tm_sec) << 0
172 | bin2bcd(tm.tm_min) << 8
173 | bin2bcd(tm.tm_hour) << 16
174 | AT91_RTC_HOUREN | AT91_RTC_MINEN | AT91_RTC_SECEN);
175 at91_rtc_write(AT91_RTC_CALALR,
176 bin2bcd(tm.tm_mon + 1) << 16 /* tm_mon starts at zero */
177 | bin2bcd(tm.tm_mday) << 24
178 | AT91_RTC_DATEEN | AT91_RTC_MTHEN);
179
180 if (alrm->enabled) {
181 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
182 at91_rtc_write(AT91_RTC_IER, AT91_RTC_ALARM);
183 }
184
185 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
186 at91_alarm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour,
187 tm.tm_min, tm.tm_sec);
188
189 return 0;
190}
191
192static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
193{
194 pr_debug("%s(): cmd=%08x\n", __func__, enabled);
195
196 if (enabled) {
197 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
198 at91_rtc_write(AT91_RTC_IER, AT91_RTC_ALARM);
199 } else
200 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM);
201
202 return 0;
203}
204/*
205 * Provide additional RTC information in /proc/driver/rtc
206 */
207static int at91_rtc_proc(struct device *dev, struct seq_file *seq)
208{
209 unsigned long imr = at91_rtc_read(AT91_RTC_IMR);
210
211 seq_printf(seq, "update_IRQ\t: %s\n",
212 (imr & AT91_RTC_ACKUPD) ? "yes" : "no");
213 seq_printf(seq, "periodic_IRQ\t: %s\n",
214 (imr & AT91_RTC_SECEV) ? "yes" : "no");
215
216 return 0;
217}
218
219/*
220 * IRQ handler for the RTC
221 */
222static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
223{
224 struct platform_device *pdev = dev_id;
225 struct rtc_device *rtc = platform_get_drvdata(pdev);
226 unsigned int rtsr;
227 unsigned long events = 0;
228
229 rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read(AT91_RTC_IMR);
230 if (rtsr) { /* this interrupt is shared! Is it ours? */
231 if (rtsr & AT91_RTC_ALARM)
232 events |= (RTC_AF | RTC_IRQF);
233 if (rtsr & AT91_RTC_SECEV)
234 events |= (RTC_UF | RTC_IRQF);
235 if (rtsr & AT91_RTC_ACKUPD)
236 complete(&at91_rtc_updated);
237
238 at91_rtc_write(AT91_RTC_SCCR, rtsr); /* clear status reg */
239
240 rtc_update_irq(rtc, 1, events);
241
242 pr_debug("%s(): num=%ld, events=0x%02lx\n", __func__,
243 events >> 8, events & 0x000000FF);
244
245 return IRQ_HANDLED;
246 }
247 return IRQ_NONE; /* not handled */
248}
249
250static const struct rtc_class_ops at91_rtc_ops = {
251 .read_time = at91_rtc_readtime,
252 .set_time = at91_rtc_settime,
253 .read_alarm = at91_rtc_readalarm,
254 .set_alarm = at91_rtc_setalarm,
255 .proc = at91_rtc_proc,
256 .alarm_irq_enable = at91_rtc_alarm_irq_enable,
257};
258
259/*
260 * Initialize and install RTC driver
261 */
262static int __init at91_rtc_probe(struct platform_device *pdev)
263{
264 struct rtc_device *rtc;
265 struct resource *regs;
266 int ret = 0;
267
268 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
269 if (!regs) {
270 dev_err(&pdev->dev, "no mmio resource defined\n");
271 return -ENXIO;
272 }
273
274 irq = platform_get_irq(pdev, 0);
275 if (irq < 0) {
276 dev_err(&pdev->dev, "no irq resource defined\n");
277 return -ENXIO;
278 }
279
280 at91_rtc_regs = ioremap(regs->start, resource_size(regs));
281 if (!at91_rtc_regs) {
282 dev_err(&pdev->dev, "failed to map registers, aborting.\n");
283 return -ENOMEM;
284 }
285
286 at91_rtc_write(AT91_RTC_CR, 0);
287 at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */
288
289 /* Disable all interrupts */
290 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
291 AT91_RTC_SECEV | AT91_RTC_TIMEV |
292 AT91_RTC_CALEV);
293
294 ret = request_irq(irq, at91_rtc_interrupt,
295 IRQF_SHARED,
296 "at91_rtc", pdev);
297 if (ret) {
298 printk(KERN_ERR "at91_rtc: IRQ %d already in use.\n",
299 irq);
300 return ret;
301 }
302
303 /* cpu init code should really have flagged this device as
304 * being wake-capable; if it didn't, do that here.
305 */
306 if (!device_can_wakeup(&pdev->dev))
307 device_init_wakeup(&pdev->dev, 1);
308
309 rtc = rtc_device_register(pdev->name, &pdev->dev,
310 &at91_rtc_ops, THIS_MODULE);
311 if (IS_ERR(rtc)) {
312 free_irq(irq, pdev);
313 return PTR_ERR(rtc);
314 }
315 platform_set_drvdata(pdev, rtc);
316
317 printk(KERN_INFO "AT91 Real Time Clock driver.\n");
318 return 0;
319}
320
321/*
322 * Disable and remove the RTC driver
323 */
324static int __exit at91_rtc_remove(struct platform_device *pdev)
325{
326 struct rtc_device *rtc = platform_get_drvdata(pdev);
327
328 /* Disable all interrupts */
329 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
330 AT91_RTC_SECEV | AT91_RTC_TIMEV |
331 AT91_RTC_CALEV);
332 free_irq(irq, pdev);
333
334 rtc_device_unregister(rtc);
335 platform_set_drvdata(pdev, NULL);
336
337 return 0;
338}
339
340#ifdef CONFIG_PM
341
342/* AT91RM9200 RTC Power management control */
343
344static u32 at91_rtc_imr;
345
346static int at91_rtc_suspend(struct device *dev)
347{
348 /* this IRQ is shared with DBGU and other hardware which isn't
349 * necessarily doing PM like we are...
350 */
351 at91_rtc_imr = at91_rtc_read(AT91_RTC_IMR)
352 & (AT91_RTC_ALARM|AT91_RTC_SECEV);
353 if (at91_rtc_imr) {
354 if (device_may_wakeup(dev))
355 enable_irq_wake(irq);
356 else
357 at91_rtc_write(AT91_RTC_IDR, at91_rtc_imr);
358 }
359 return 0;
360}
361
362static int at91_rtc_resume(struct device *dev)
363{
364 if (at91_rtc_imr) {
365 if (device_may_wakeup(dev))
366 disable_irq_wake(irq);
367 else
368 at91_rtc_write(AT91_RTC_IER, at91_rtc_imr);
369 }
370 return 0;
371}
372
373static const struct dev_pm_ops at91_rtc_pm = {
374 .suspend = at91_rtc_suspend,
375 .resume = at91_rtc_resume,
376};
377
378#define at91_rtc_pm_ptr &at91_rtc_pm
379
380#else
381#define at91_rtc_pm_ptr NULL
382#endif
383
384static struct platform_driver at91_rtc_driver = {
385 .remove = __exit_p(at91_rtc_remove),
386 .driver = {
387 .name = "at91_rtc",
388 .owner = THIS_MODULE,
389 .pm = at91_rtc_pm_ptr,
390 },
391};
392
393static int __init at91_rtc_init(void)
394{
395 return platform_driver_probe(&at91_rtc_driver, at91_rtc_probe);
396}
397
398static void __exit at91_rtc_exit(void)
399{
400 platform_driver_unregister(&at91_rtc_driver);
401}
402
403module_init(at91_rtc_init);
404module_exit(at91_rtc_exit);
405
406MODULE_AUTHOR("Rick Bronson");
407MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200");
408MODULE_LICENSE("GPL");
409MODULE_ALIAS("platform:at91_rtc");
1/*
2 * Real Time Clock interface for Linux on Atmel AT91RM9200
3 *
4 * Copyright (C) 2002 Rick Bronson
5 *
6 * Converted to RTC class model by Andrew Victor
7 *
8 * Ported to Linux 2.6 by Steven Scholz
9 * Based on s3c2410-rtc.c Simtec Electronics
10 *
11 * Based on sa1100-rtc.c by Nils Faerber
12 * Based on rtc.c by Paul Gortmaker
13 *
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public License
16 * as published by the Free Software Foundation; either version
17 * 2 of the License, or (at your option) any later version.
18 *
19 */
20
21#include <linux/module.h>
22#include <linux/kernel.h>
23#include <linux/platform_device.h>
24#include <linux/time.h>
25#include <linux/rtc.h>
26#include <linux/bcd.h>
27#include <linux/interrupt.h>
28#include <linux/spinlock.h>
29#include <linux/ioctl.h>
30#include <linux/completion.h>
31#include <linux/io.h>
32#include <linux/of.h>
33#include <linux/of_device.h>
34#include <linux/uaccess.h>
35
36#include "rtc-at91rm9200.h"
37
38#define at91_rtc_read(field) \
39 __raw_readl(at91_rtc_regs + field)
40#define at91_rtc_write(field, val) \
41 __raw_writel((val), at91_rtc_regs + field)
42
43#define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */
44
45struct at91_rtc_config {
46 bool use_shadow_imr;
47};
48
49static const struct at91_rtc_config *at91_rtc_config;
50static DECLARE_COMPLETION(at91_rtc_updated);
51static unsigned int at91_alarm_year = AT91_RTC_EPOCH;
52static void __iomem *at91_rtc_regs;
53static int irq;
54static DEFINE_SPINLOCK(at91_rtc_lock);
55static u32 at91_rtc_shadow_imr;
56
57static void at91_rtc_write_ier(u32 mask)
58{
59 unsigned long flags;
60
61 spin_lock_irqsave(&at91_rtc_lock, flags);
62 at91_rtc_shadow_imr |= mask;
63 at91_rtc_write(AT91_RTC_IER, mask);
64 spin_unlock_irqrestore(&at91_rtc_lock, flags);
65}
66
67static void at91_rtc_write_idr(u32 mask)
68{
69 unsigned long flags;
70
71 spin_lock_irqsave(&at91_rtc_lock, flags);
72 at91_rtc_write(AT91_RTC_IDR, mask);
73 /*
74 * Register read back (of any RTC-register) needed to make sure
75 * IDR-register write has reached the peripheral before updating
76 * shadow mask.
77 *
78 * Note that there is still a possibility that the mask is updated
79 * before interrupts have actually been disabled in hardware. The only
80 * way to be certain would be to poll the IMR-register, which is is
81 * the very register we are trying to emulate. The register read back
82 * is a reasonable heuristic.
83 */
84 at91_rtc_read(AT91_RTC_SR);
85 at91_rtc_shadow_imr &= ~mask;
86 spin_unlock_irqrestore(&at91_rtc_lock, flags);
87}
88
89static u32 at91_rtc_read_imr(void)
90{
91 unsigned long flags;
92 u32 mask;
93
94 if (at91_rtc_config->use_shadow_imr) {
95 spin_lock_irqsave(&at91_rtc_lock, flags);
96 mask = at91_rtc_shadow_imr;
97 spin_unlock_irqrestore(&at91_rtc_lock, flags);
98 } else {
99 mask = at91_rtc_read(AT91_RTC_IMR);
100 }
101
102 return mask;
103}
104
105/*
106 * Decode time/date into rtc_time structure
107 */
108static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg,
109 struct rtc_time *tm)
110{
111 unsigned int time, date;
112
113 /* must read twice in case it changes */
114 do {
115 time = at91_rtc_read(timereg);
116 date = at91_rtc_read(calreg);
117 } while ((time != at91_rtc_read(timereg)) ||
118 (date != at91_rtc_read(calreg)));
119
120 tm->tm_sec = bcd2bin((time & AT91_RTC_SEC) >> 0);
121 tm->tm_min = bcd2bin((time & AT91_RTC_MIN) >> 8);
122 tm->tm_hour = bcd2bin((time & AT91_RTC_HOUR) >> 16);
123
124 /*
125 * The Calendar Alarm register does not have a field for
126 * the year - so these will return an invalid value. When an
127 * alarm is set, at91_alarm_year will store the current year.
128 */
129 tm->tm_year = bcd2bin(date & AT91_RTC_CENT) * 100; /* century */
130 tm->tm_year += bcd2bin((date & AT91_RTC_YEAR) >> 8); /* year */
131
132 tm->tm_wday = bcd2bin((date & AT91_RTC_DAY) >> 21) - 1; /* day of the week [0-6], Sunday=0 */
133 tm->tm_mon = bcd2bin((date & AT91_RTC_MONTH) >> 16) - 1;
134 tm->tm_mday = bcd2bin((date & AT91_RTC_DATE) >> 24);
135}
136
137/*
138 * Read current time and date in RTC
139 */
140static int at91_rtc_readtime(struct device *dev, struct rtc_time *tm)
141{
142 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm);
143 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
144 tm->tm_year = tm->tm_year - 1900;
145
146 dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
147 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
148 tm->tm_hour, tm->tm_min, tm->tm_sec);
149
150 return 0;
151}
152
153/*
154 * Set current time and date in RTC
155 */
156static int at91_rtc_settime(struct device *dev, struct rtc_time *tm)
157{
158 unsigned long cr;
159
160 dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
161 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
162 tm->tm_hour, tm->tm_min, tm->tm_sec);
163
164 /* Stop Time/Calendar from counting */
165 cr = at91_rtc_read(AT91_RTC_CR);
166 at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM);
167
168 at91_rtc_write_ier(AT91_RTC_ACKUPD);
169 wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
170 at91_rtc_write_idr(AT91_RTC_ACKUPD);
171
172 at91_rtc_write(AT91_RTC_TIMR,
173 bin2bcd(tm->tm_sec) << 0
174 | bin2bcd(tm->tm_min) << 8
175 | bin2bcd(tm->tm_hour) << 16);
176
177 at91_rtc_write(AT91_RTC_CALR,
178 bin2bcd((tm->tm_year + 1900) / 100) /* century */
179 | bin2bcd(tm->tm_year % 100) << 8 /* year */
180 | bin2bcd(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */
181 | bin2bcd(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */
182 | bin2bcd(tm->tm_mday) << 24);
183
184 /* Restart Time/Calendar */
185 cr = at91_rtc_read(AT91_RTC_CR);
186 at91_rtc_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM));
187
188 return 0;
189}
190
191/*
192 * Read alarm time and date in RTC
193 */
194static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
195{
196 struct rtc_time *tm = &alrm->time;
197
198 at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm);
199 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
200 tm->tm_year = at91_alarm_year - 1900;
201
202 alrm->enabled = (at91_rtc_read_imr() & AT91_RTC_ALARM)
203 ? 1 : 0;
204
205 dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
206 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
207 tm->tm_hour, tm->tm_min, tm->tm_sec);
208
209 return 0;
210}
211
212/*
213 * Set alarm time and date in RTC
214 */
215static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
216{
217 struct rtc_time tm;
218
219 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm);
220
221 at91_alarm_year = tm.tm_year;
222
223 tm.tm_mon = alrm->time.tm_mon;
224 tm.tm_mday = alrm->time.tm_mday;
225 tm.tm_hour = alrm->time.tm_hour;
226 tm.tm_min = alrm->time.tm_min;
227 tm.tm_sec = alrm->time.tm_sec;
228
229 at91_rtc_write_idr(AT91_RTC_ALARM);
230 at91_rtc_write(AT91_RTC_TIMALR,
231 bin2bcd(tm.tm_sec) << 0
232 | bin2bcd(tm.tm_min) << 8
233 | bin2bcd(tm.tm_hour) << 16
234 | AT91_RTC_HOUREN | AT91_RTC_MINEN | AT91_RTC_SECEN);
235 at91_rtc_write(AT91_RTC_CALALR,
236 bin2bcd(tm.tm_mon + 1) << 16 /* tm_mon starts at zero */
237 | bin2bcd(tm.tm_mday) << 24
238 | AT91_RTC_DATEEN | AT91_RTC_MTHEN);
239
240 if (alrm->enabled) {
241 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
242 at91_rtc_write_ier(AT91_RTC_ALARM);
243 }
244
245 dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
246 at91_alarm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour,
247 tm.tm_min, tm.tm_sec);
248
249 return 0;
250}
251
252static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
253{
254 dev_dbg(dev, "%s(): cmd=%08x\n", __func__, enabled);
255
256 if (enabled) {
257 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
258 at91_rtc_write_ier(AT91_RTC_ALARM);
259 } else
260 at91_rtc_write_idr(AT91_RTC_ALARM);
261
262 return 0;
263}
264/*
265 * Provide additional RTC information in /proc/driver/rtc
266 */
267static int at91_rtc_proc(struct device *dev, struct seq_file *seq)
268{
269 unsigned long imr = at91_rtc_read_imr();
270
271 seq_printf(seq, "update_IRQ\t: %s\n",
272 (imr & AT91_RTC_ACKUPD) ? "yes" : "no");
273 seq_printf(seq, "periodic_IRQ\t: %s\n",
274 (imr & AT91_RTC_SECEV) ? "yes" : "no");
275
276 return 0;
277}
278
279/*
280 * IRQ handler for the RTC
281 */
282static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
283{
284 struct platform_device *pdev = dev_id;
285 struct rtc_device *rtc = platform_get_drvdata(pdev);
286 unsigned int rtsr;
287 unsigned long events = 0;
288
289 rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read_imr();
290 if (rtsr) { /* this interrupt is shared! Is it ours? */
291 if (rtsr & AT91_RTC_ALARM)
292 events |= (RTC_AF | RTC_IRQF);
293 if (rtsr & AT91_RTC_SECEV)
294 events |= (RTC_UF | RTC_IRQF);
295 if (rtsr & AT91_RTC_ACKUPD)
296 complete(&at91_rtc_updated);
297
298 at91_rtc_write(AT91_RTC_SCCR, rtsr); /* clear status reg */
299
300 rtc_update_irq(rtc, 1, events);
301
302 dev_dbg(&pdev->dev, "%s(): num=%ld, events=0x%02lx\n", __func__,
303 events >> 8, events & 0x000000FF);
304
305 return IRQ_HANDLED;
306 }
307 return IRQ_NONE; /* not handled */
308}
309
310static const struct at91_rtc_config at91rm9200_config = {
311};
312
313static const struct at91_rtc_config at91sam9x5_config = {
314 .use_shadow_imr = true,
315};
316
317#ifdef CONFIG_OF
318static const struct of_device_id at91_rtc_dt_ids[] = {
319 {
320 .compatible = "atmel,at91rm9200-rtc",
321 .data = &at91rm9200_config,
322 }, {
323 .compatible = "atmel,at91sam9x5-rtc",
324 .data = &at91sam9x5_config,
325 }, {
326 /* sentinel */
327 }
328};
329MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids);
330#endif
331
332static const struct at91_rtc_config *
333at91_rtc_get_config(struct platform_device *pdev)
334{
335 const struct of_device_id *match;
336
337 if (pdev->dev.of_node) {
338 match = of_match_node(at91_rtc_dt_ids, pdev->dev.of_node);
339 if (!match)
340 return NULL;
341 return (const struct at91_rtc_config *)match->data;
342 }
343
344 return &at91rm9200_config;
345}
346
347static const struct rtc_class_ops at91_rtc_ops = {
348 .read_time = at91_rtc_readtime,
349 .set_time = at91_rtc_settime,
350 .read_alarm = at91_rtc_readalarm,
351 .set_alarm = at91_rtc_setalarm,
352 .proc = at91_rtc_proc,
353 .alarm_irq_enable = at91_rtc_alarm_irq_enable,
354};
355
356/*
357 * Initialize and install RTC driver
358 */
359static int __init at91_rtc_probe(struct platform_device *pdev)
360{
361 struct rtc_device *rtc;
362 struct resource *regs;
363 int ret = 0;
364
365 at91_rtc_config = at91_rtc_get_config(pdev);
366 if (!at91_rtc_config)
367 return -ENODEV;
368
369 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
370 if (!regs) {
371 dev_err(&pdev->dev, "no mmio resource defined\n");
372 return -ENXIO;
373 }
374
375 irq = platform_get_irq(pdev, 0);
376 if (irq < 0) {
377 dev_err(&pdev->dev, "no irq resource defined\n");
378 return -ENXIO;
379 }
380
381 at91_rtc_regs = devm_ioremap(&pdev->dev, regs->start,
382 resource_size(regs));
383 if (!at91_rtc_regs) {
384 dev_err(&pdev->dev, "failed to map registers, aborting.\n");
385 return -ENOMEM;
386 }
387
388 at91_rtc_write(AT91_RTC_CR, 0);
389 at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */
390
391 /* Disable all interrupts */
392 at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM |
393 AT91_RTC_SECEV | AT91_RTC_TIMEV |
394 AT91_RTC_CALEV);
395
396 ret = devm_request_irq(&pdev->dev, irq, at91_rtc_interrupt,
397 IRQF_SHARED,
398 "at91_rtc", pdev);
399 if (ret) {
400 dev_err(&pdev->dev, "IRQ %d already in use.\n", irq);
401 return ret;
402 }
403
404 /* cpu init code should really have flagged this device as
405 * being wake-capable; if it didn't, do that here.
406 */
407 if (!device_can_wakeup(&pdev->dev))
408 device_init_wakeup(&pdev->dev, 1);
409
410 rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
411 &at91_rtc_ops, THIS_MODULE);
412 if (IS_ERR(rtc))
413 return PTR_ERR(rtc);
414 platform_set_drvdata(pdev, rtc);
415
416 dev_info(&pdev->dev, "AT91 Real Time Clock driver.\n");
417 return 0;
418}
419
420/*
421 * Disable and remove the RTC driver
422 */
423static int __exit at91_rtc_remove(struct platform_device *pdev)
424{
425 /* Disable all interrupts */
426 at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM |
427 AT91_RTC_SECEV | AT91_RTC_TIMEV |
428 AT91_RTC_CALEV);
429
430 return 0;
431}
432
433static void at91_rtc_shutdown(struct platform_device *pdev)
434{
435 /* Disable all interrupts */
436 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
437 AT91_RTC_SECEV | AT91_RTC_TIMEV |
438 AT91_RTC_CALEV);
439}
440
441#ifdef CONFIG_PM_SLEEP
442
443/* AT91RM9200 RTC Power management control */
444
445static u32 at91_rtc_imr;
446
447static int at91_rtc_suspend(struct device *dev)
448{
449 /* this IRQ is shared with DBGU and other hardware which isn't
450 * necessarily doing PM like we are...
451 */
452 at91_rtc_imr = at91_rtc_read_imr()
453 & (AT91_RTC_ALARM|AT91_RTC_SECEV);
454 if (at91_rtc_imr) {
455 if (device_may_wakeup(dev))
456 enable_irq_wake(irq);
457 else
458 at91_rtc_write_idr(at91_rtc_imr);
459 }
460 return 0;
461}
462
463static int at91_rtc_resume(struct device *dev)
464{
465 if (at91_rtc_imr) {
466 if (device_may_wakeup(dev))
467 disable_irq_wake(irq);
468 else
469 at91_rtc_write_ier(at91_rtc_imr);
470 }
471 return 0;
472}
473#endif
474
475static SIMPLE_DEV_PM_OPS(at91_rtc_pm_ops, at91_rtc_suspend, at91_rtc_resume);
476
477static struct platform_driver at91_rtc_driver = {
478 .remove = __exit_p(at91_rtc_remove),
479 .shutdown = at91_rtc_shutdown,
480 .driver = {
481 .name = "at91_rtc",
482 .owner = THIS_MODULE,
483 .pm = &at91_rtc_pm_ops,
484 .of_match_table = of_match_ptr(at91_rtc_dt_ids),
485 },
486};
487
488module_platform_driver_probe(at91_rtc_driver, at91_rtc_probe);
489
490MODULE_AUTHOR("Rick Bronson");
491MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200");
492MODULE_LICENSE("GPL");
493MODULE_ALIAS("platform:at91_rtc");