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-rw-r--r--drivers/rtc/Kconfig6
-rw-r--r--drivers/rtc/Makefile1
-rw-r--r--drivers/rtc/rtc-at91.c388
3 files changed, 395 insertions, 0 deletions
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 8534012ebdef..0bfd3aad6179 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -202,6 +202,12 @@ config RTC_DRV_PL031
202 To compile this driver as a module, choose M here: the 202 To compile this driver as a module, choose M here: the
203 module will be called rtc-pl031. 203 module will be called rtc-pl031.
204 204
205config RTC_DRV_AT91
206 tristate "AT91RM9200"
207 depends on RTC_CLASS && ARCH_AT91RM9200
208 help
209 Driver for the Atmel AT91RM9200's internal RTC (Realtime Clock).
210
205config RTC_DRV_TEST 211config RTC_DRV_TEST
206 tristate "Test driver/device" 212 tristate "Test driver/device"
207 depends on RTC_CLASS 213 depends on RTC_CLASS
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index cbb8e8a7f620..f39992b865ce 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -25,3 +25,4 @@ obj-$(CONFIG_RTC_DRV_VR41XX) += rtc-vr41xx.o
25obj-$(CONFIG_RTC_DRV_PL031) += rtc-pl031.o 25obj-$(CONFIG_RTC_DRV_PL031) += rtc-pl031.o
26obj-$(CONFIG_RTC_DRV_MAX6902) += rtc-max6902.o 26obj-$(CONFIG_RTC_DRV_MAX6902) += rtc-max6902.o
27obj-$(CONFIG_RTC_DRV_V3020) += rtc-v3020.o 27obj-$(CONFIG_RTC_DRV_V3020) += rtc-v3020.o
28obj-$(CONFIG_RTC_DRV_AT91) += rtc-at91.o
diff --git a/drivers/rtc/rtc-at91.c b/drivers/rtc/rtc-at91.c
new file mode 100644
index 000000000000..b03aba5f39eb
--- /dev/null
+++ b/drivers/rtc/rtc-at91.c
@@ -0,0 +1,388 @@
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#include <asm/rtc.h>
33
34#include <asm/mach/time.h>
35
36
37#define AT91_RTC_FREQ 1
38#define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */
39
40static DECLARE_COMPLETION(at91_rtc_updated);
41static unsigned int at91_alarm_year = AT91_RTC_EPOCH;
42
43
44/*
45 * Decode time/date into rtc_time structure
46 */
47static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg, struct rtc_time *tm)
48{
49 unsigned int time, date;
50
51 /* must read twice in case it changes */
52 do {
53 time = at91_sys_read(timereg);
54 date = at91_sys_read(calreg);
55 } while ((time != at91_sys_read(timereg)) || (date != at91_sys_read(calreg)));
56
57 tm->tm_sec = BCD2BIN((time & AT91_RTC_SEC) >> 0);
58 tm->tm_min = BCD2BIN((time & AT91_RTC_MIN) >> 8);
59 tm->tm_hour = BCD2BIN((time & AT91_RTC_HOUR) >> 16);
60
61 /*
62 * The Calendar Alarm register does not have a field for
63 * the year - so these will return an invalid value. When an
64 * alarm is set, at91_alarm_year wille store the current year.
65 */
66 tm->tm_year = BCD2BIN(date & AT91_RTC_CENT) * 100; /* century */
67 tm->tm_year += BCD2BIN((date & AT91_RTC_YEAR) >> 8); /* year */
68
69 tm->tm_wday = BCD2BIN((date & AT91_RTC_DAY) >> 21) - 1; /* day of the week [0-6], Sunday=0 */
70 tm->tm_mon = BCD2BIN((date & AT91_RTC_MONTH) >> 16) - 1;
71 tm->tm_mday = BCD2BIN((date & AT91_RTC_DATE) >> 24);
72}
73
74/*
75 * Read current time and date in RTC
76 */
77static int at91_rtc_readtime(struct device *dev, struct rtc_time *tm)
78{
79 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm);
80 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
81 tm->tm_year = tm->tm_year - 1900;
82
83 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __FUNCTION__,
84 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec);
85
86 return 0;
87}
88
89/*
90 * Set current time and date in RTC
91 */
92static int at91_rtc_settime(struct device *dev, struct rtc_time *tm)
93{
94 unsigned long cr;
95
96 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __FUNCTION__,
97 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec);
98
99 /* Stop Time/Calendar from counting */
100 cr = at91_sys_read(AT91_RTC_CR);
101 at91_sys_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM);
102
103 at91_sys_write(AT91_RTC_IER, AT91_RTC_ACKUPD);
104 wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
105 at91_sys_write(AT91_RTC_IDR, AT91_RTC_ACKUPD);
106
107 at91_sys_write(AT91_RTC_TIMR,
108 BIN2BCD(tm->tm_sec) << 0
109 | BIN2BCD(tm->tm_min) << 8
110 | BIN2BCD(tm->tm_hour) << 16);
111
112 at91_sys_write(AT91_RTC_CALR,
113 BIN2BCD((tm->tm_year + 1900) / 100) /* century */
114 | BIN2BCD(tm->tm_year % 100) << 8 /* year */
115 | BIN2BCD(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */
116 | BIN2BCD(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */
117 | BIN2BCD(tm->tm_mday) << 24);
118
119 /* Restart Time/Calendar */
120 cr = at91_sys_read(AT91_RTC_CR);
121 at91_sys_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM));
122
123 return 0;
124}
125
126/*
127 * Read alarm time and date in RTC
128 */
129static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
130{
131 struct rtc_time *tm = &alrm->time;
132
133 at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm);
134 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
135 tm->tm_year = at91_alarm_year - 1900;
136
137 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __FUNCTION__,
138 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec);
139
140 return 0;
141}
142
143/*
144 * Set alarm time and date in RTC
145 */
146static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
147{
148 struct rtc_time tm;
149
150 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm);
151
152 at91_alarm_year = tm.tm_year;
153
154 tm.tm_hour = alrm->time.tm_hour;
155 tm.tm_min = alrm->time.tm_min;
156 tm.tm_sec = alrm->time.tm_sec;
157
158 at91_sys_write(AT91_RTC_TIMALR,
159 BIN2BCD(tm.tm_sec) << 0
160 | BIN2BCD(tm.tm_min) << 8
161 | BIN2BCD(tm.tm_hour) << 16
162 | AT91_RTC_HOUREN | AT91_RTC_MINEN | AT91_RTC_SECEN);
163 at91_sys_write(AT91_RTC_CALALR,
164 BIN2BCD(tm.tm_mon + 1) << 16 /* tm_mon starts at zero */
165 | BIN2BCD(tm.tm_mday) << 24
166 | AT91_RTC_DATEEN | AT91_RTC_MTHEN);
167
168 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __FUNCTION__,
169 at91_alarm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec);
170
171 return 0;
172}
173
174/*
175 * Handle commands from user-space
176 */
177static int at91_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
178{
179 int ret = 0;
180
181 pr_debug("%s(): cmd=%08x, arg=%08lx.\n", __FUNCTION__, cmd, arg);
182
183 switch (cmd) {
184 case RTC_AIE_OFF: /* alarm off */
185 at91_sys_write(AT91_RTC_IDR, AT91_RTC_ALARM);
186 break;
187 case RTC_AIE_ON: /* alarm on */
188 at91_sys_write(AT91_RTC_IER, AT91_RTC_ALARM);
189 break;
190 case RTC_UIE_OFF: /* update off */
191 case RTC_PIE_OFF: /* periodic off */
192 at91_sys_write(AT91_RTC_IDR, AT91_RTC_SECEV);
193 break;
194 case RTC_UIE_ON: /* update on */
195 case RTC_PIE_ON: /* periodic on */
196 at91_sys_write(AT91_RTC_IER, AT91_RTC_SECEV);
197 break;
198 case RTC_IRQP_READ: /* read periodic alarm frequency */
199 ret = put_user(AT91_RTC_FREQ, (unsigned long *) arg);
200 break;
201 case RTC_IRQP_SET: /* set periodic alarm frequency */
202 if (arg != AT91_RTC_FREQ)
203 ret = -EINVAL;
204 break;
205 default:
206 ret = -ENOIOCTLCMD;
207 break;
208 }
209
210 return ret;
211}
212
213/*
214 * Provide additional RTC information in /proc/driver/rtc
215 */
216static int at91_rtc_proc(struct device *dev, struct seq_file *seq)
217{
218 unsigned long imr = at91_sys_read(AT91_RTC_IMR);
219
220 seq_printf(seq, "alarm_IRQ\t: %s\n", (imr & AT91_RTC_ALARM) ? "yes" : "no");
221 seq_printf(seq, "update_IRQ\t: %s\n", (imr & AT91_RTC_ACKUPD) ? "yes" : "no");
222 seq_printf(seq, "periodic_IRQ\t: %s\n", (imr & AT91_RTC_SECEV) ? "yes" : "no");
223 seq_printf(seq, "periodic_freq\t: %ld\n", (unsigned long) AT91_RTC_FREQ);
224
225 return 0;
226}
227
228/*
229 * IRQ handler for the RTC
230 */
231static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs)
232{
233 struct platform_device *pdev = (struct platform_device *)dev_id;
234 struct rtc_device *rtc = platform_get_drvdata(pdev);
235 unsigned int rtsr;
236 unsigned long events = 0;
237
238 rtsr = at91_sys_read(AT91_RTC_SR) & at91_sys_read(AT91_RTC_IMR);
239 if (rtsr) { /* this interrupt is shared! Is it ours? */
240 if (rtsr & AT91_RTC_ALARM)
241 events |= (RTC_AF | RTC_IRQF);
242 if (rtsr & AT91_RTC_SECEV)
243 events |= (RTC_UF | RTC_IRQF);
244 if (rtsr & AT91_RTC_ACKUPD)
245 complete(&at91_rtc_updated);
246
247 at91_sys_write(AT91_RTC_SCCR, rtsr); /* clear status reg */
248
249 rtc_update_irq(&rtc->class_dev, 1, events);
250
251 pr_debug("%s(): num=%ld, events=0x%02lx\n", __FUNCTION__,
252 events >> 8, events & 0x000000FF);
253
254 return IRQ_HANDLED;
255 }
256 return IRQ_NONE; /* not handled */
257}
258
259static struct rtc_class_ops at91_rtc_ops = {
260 .ioctl = at91_rtc_ioctl,
261 .read_time = at91_rtc_readtime,
262 .set_time = at91_rtc_settime,
263 .read_alarm = at91_rtc_readalarm,
264 .set_alarm = at91_rtc_setalarm,
265 .proc = at91_rtc_proc,
266};
267
268/*
269 * Initialize and install RTC driver
270 */
271static int __init at91_rtc_probe(struct platform_device *pdev)
272{
273 struct rtc_device *rtc;
274 int ret;
275
276 at91_sys_write(AT91_RTC_CR, 0);
277 at91_sys_write(AT91_RTC_MR, 0); /* 24 hour mode */
278
279 /* Disable all interrupts */
280 at91_sys_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM | AT91_RTC_SECEV | AT91_RTC_TIMEV | AT91_RTC_CALEV);
281
282 ret = request_irq(AT91_ID_SYS, at91_rtc_interrupt, SA_SHIRQ, "at91_rtc", pdev);
283 if (ret) {
284 printk(KERN_ERR "at91_rtc: IRQ %d already in use.\n", AT91_ID_SYS);
285 return ret;
286 }
287
288 rtc = rtc_device_register(pdev->name, &pdev->dev, &at91_rtc_ops, THIS_MODULE);
289 if (IS_ERR(rtc)) {
290 free_irq(AT91_ID_SYS, pdev);
291 return PTR_ERR(rtc);
292 }
293 platform_set_drvdata(pdev, rtc);
294
295 printk(KERN_INFO "AT91 Real Time Clock driver.\n");
296 return 0;
297}
298
299/*
300 * Disable and remove the RTC driver
301 */
302static int __devexit at91_rtc_remove(struct platform_device *pdev)
303{
304 struct rtc_device *rtc = platform_get_drvdata(pdev);
305
306 /* Disable all interrupts */
307 at91_sys_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM | AT91_RTC_SECEV | AT91_RTC_TIMEV | AT91_RTC_CALEV);
308 free_irq(AT91_ID_SYS, pdev);
309
310 rtc_device_unregister(rtc);
311 platform_set_drvdata(pdev, NULL);
312
313 return 0;
314}
315
316#ifdef CONFIG_PM
317
318/* AT91RM9200 RTC Power management control */
319
320static struct timespec at91_rtc_delta;
321
322static int at91_rtc_suspend(struct platform_device *pdev, pm_message_t state)
323{
324 struct rtc_time tm;
325 struct timespec time;
326
327 time.tv_nsec = 0;
328
329 /* calculate time delta for suspend */
330 at91_rtc_readtime(&pdev->dev, &tm);
331 rtc_tm_to_time(&tm, &time.tv_sec);
332 save_time_delta(&at91_rtc_delta, &time);
333
334 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __FUNCTION__,
335 1900 + tm.tm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec);
336
337 return 0;
338}
339
340static int at91_rtc_resume(struct platform_device *pdev)
341{
342 struct rtc_time tm;
343 struct timespec time;
344
345 time.tv_nsec = 0;
346
347 at91_rtc_readtime(&pdev->dev, &tm);
348 rtc_tm_to_time(&tm, &time.tv_sec);
349 restore_time_delta(&at91_rtc_delta, &time);
350
351 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __FUNCTION__,
352 1900 + tm.tm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec);
353
354 return 0;
355}
356#else
357#define at91_rtc_suspend NULL
358#define at91_rtc_resume NULL
359#endif
360
361static struct platform_driver at91_rtc_driver = {
362 .probe = at91_rtc_probe,
363 .remove = at91_rtc_remove,
364 .suspend = at91_rtc_suspend,
365 .resume = at91_rtc_resume,
366 .driver = {
367 .name = "at91_rtc",
368 .owner = THIS_MODULE,
369 },
370};
371
372static int __init at91_rtc_init(void)
373{
374 return platform_driver_register(&at91_rtc_driver);
375}
376
377static void __exit at91_rtc_exit(void)
378{
379 platform_driver_unregister(&at91_rtc_driver);
380}
381
382
383module_init(at91_rtc_init);
384module_exit(at91_rtc_exit);
385
386MODULE_AUTHOR("Rick Bronson");
387MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200");
388MODULE_LICENSE("GPL");