Root/
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 | |
36 | #define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */ |
37 | |
38 | static DECLARE_COMPLETION(at91_rtc_updated); |
39 | static unsigned int at91_alarm_year = AT91_RTC_EPOCH; |
40 | |
41 | /* |
42 | * Decode time/date into rtc_time structure |
43 | */ |
44 | static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg, |
45 | struct rtc_time *tm) |
46 | { |
47 | unsigned int time, date; |
48 | |
49 | /* must read twice in case it changes */ |
50 | do { |
51 | time = at91_sys_read(timereg); |
52 | date = at91_sys_read(calreg); |
53 | } while ((time != at91_sys_read(timereg)) || |
54 | (date != at91_sys_read(calreg))); |
55 | |
56 | tm->tm_sec = bcd2bin((time & AT91_RTC_SEC) >> 0); |
57 | tm->tm_min = bcd2bin((time & AT91_RTC_MIN) >> 8); |
58 | tm->tm_hour = bcd2bin((time & AT91_RTC_HOUR) >> 16); |
59 | |
60 | /* |
61 | * The Calendar Alarm register does not have a field for |
62 | * the year - so these will return an invalid value. When an |
63 | * alarm is set, at91_alarm_year wille store the current year. |
64 | */ |
65 | tm->tm_year = bcd2bin(date & AT91_RTC_CENT) * 100; /* century */ |
66 | tm->tm_year += bcd2bin((date & AT91_RTC_YEAR) >> 8); /* year */ |
67 | |
68 | tm->tm_wday = bcd2bin((date & AT91_RTC_DAY) >> 21) - 1; /* day of the week [0-6], Sunday=0 */ |
69 | tm->tm_mon = bcd2bin((date & AT91_RTC_MONTH) >> 16) - 1; |
70 | tm->tm_mday = bcd2bin((date & AT91_RTC_DATE) >> 24); |
71 | } |
72 | |
73 | /* |
74 | * Read current time and date in RTC |
75 | */ |
76 | static int at91_rtc_readtime(struct device *dev, struct rtc_time *tm) |
77 | { |
78 | at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm); |
79 | tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); |
80 | tm->tm_year = tm->tm_year - 1900; |
81 | |
82 | pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__, |
83 | 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, |
84 | 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 | */ |
92 | static 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", __func__, |
97 | 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, |
98 | tm->tm_hour, tm->tm_min, tm->tm_sec); |
99 | |
100 | /* Stop Time/Calendar from counting */ |
101 | cr = at91_sys_read(AT91_RTC_CR); |
102 | at91_sys_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM); |
103 | |
104 | at91_sys_write(AT91_RTC_IER, AT91_RTC_ACKUPD); |
105 | wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */ |
106 | at91_sys_write(AT91_RTC_IDR, AT91_RTC_ACKUPD); |
107 | |
108 | at91_sys_write(AT91_RTC_TIMR, |
109 | bin2bcd(tm->tm_sec) << 0 |
110 | | bin2bcd(tm->tm_min) << 8 |
111 | | bin2bcd(tm->tm_hour) << 16); |
112 | |
113 | at91_sys_write(AT91_RTC_CALR, |
114 | bin2bcd((tm->tm_year + 1900) / 100) /* century */ |
115 | | bin2bcd(tm->tm_year % 100) << 8 /* year */ |
116 | | bin2bcd(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */ |
117 | | bin2bcd(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */ |
118 | | bin2bcd(tm->tm_mday) << 24); |
119 | |
120 | /* Restart Time/Calendar */ |
121 | cr = at91_sys_read(AT91_RTC_CR); |
122 | at91_sys_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM)); |
123 | |
124 | return 0; |
125 | } |
126 | |
127 | /* |
128 | * Read alarm time and date in RTC |
129 | */ |
130 | static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm) |
131 | { |
132 | struct rtc_time *tm = &alrm->time; |
133 | |
134 | at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm); |
135 | tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); |
136 | tm->tm_year = at91_alarm_year - 1900; |
137 | |
138 | alrm->enabled = (at91_sys_read(AT91_RTC_IMR) & AT91_RTC_ALARM) |
139 | ? 1 : 0; |
140 | |
141 | pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__, |
142 | 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, |
143 | tm->tm_hour, tm->tm_min, tm->tm_sec); |
144 | |
145 | return 0; |
146 | } |
147 | |
148 | /* |
149 | * Set alarm time and date in RTC |
150 | */ |
151 | static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm) |
152 | { |
153 | struct rtc_time tm; |
154 | |
155 | at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm); |
156 | |
157 | at91_alarm_year = tm.tm_year; |
158 | |
159 | tm.tm_hour = alrm->time.tm_hour; |
160 | tm.tm_min = alrm->time.tm_min; |
161 | tm.tm_sec = alrm->time.tm_sec; |
162 | |
163 | at91_sys_write(AT91_RTC_IDR, AT91_RTC_ALARM); |
164 | at91_sys_write(AT91_RTC_TIMALR, |
165 | bin2bcd(tm.tm_sec) << 0 |
166 | | bin2bcd(tm.tm_min) << 8 |
167 | | bin2bcd(tm.tm_hour) << 16 |
168 | | AT91_RTC_HOUREN | AT91_RTC_MINEN | AT91_RTC_SECEN); |
169 | at91_sys_write(AT91_RTC_CALALR, |
170 | bin2bcd(tm.tm_mon + 1) << 16 /* tm_mon starts at zero */ |
171 | | bin2bcd(tm.tm_mday) << 24 |
172 | | AT91_RTC_DATEEN | AT91_RTC_MTHEN); |
173 | |
174 | if (alrm->enabled) { |
175 | at91_sys_write(AT91_RTC_SCCR, AT91_RTC_ALARM); |
176 | at91_sys_write(AT91_RTC_IER, AT91_RTC_ALARM); |
177 | } |
178 | |
179 | pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__, |
180 | at91_alarm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour, |
181 | tm.tm_min, tm.tm_sec); |
182 | |
183 | return 0; |
184 | } |
185 | |
186 | /* |
187 | * Handle commands from user-space |
188 | */ |
189 | static int at91_rtc_ioctl(struct device *dev, unsigned int cmd, |
190 | unsigned long arg) |
191 | { |
192 | int ret = 0; |
193 | |
194 | pr_debug("%s(): cmd=%08x, arg=%08lx.\n", __func__, cmd, arg); |
195 | |
196 | /* important: scrub old status before enabling IRQs */ |
197 | switch (cmd) { |
198 | case RTC_AIE_OFF: /* alarm off */ |
199 | at91_sys_write(AT91_RTC_IDR, AT91_RTC_ALARM); |
200 | break; |
201 | case RTC_AIE_ON: /* alarm on */ |
202 | at91_sys_write(AT91_RTC_SCCR, AT91_RTC_ALARM); |
203 | at91_sys_write(AT91_RTC_IER, AT91_RTC_ALARM); |
204 | break; |
205 | case RTC_UIE_OFF: /* update off */ |
206 | at91_sys_write(AT91_RTC_IDR, AT91_RTC_SECEV); |
207 | break; |
208 | case RTC_UIE_ON: /* update on */ |
209 | at91_sys_write(AT91_RTC_SCCR, AT91_RTC_SECEV); |
210 | at91_sys_write(AT91_RTC_IER, AT91_RTC_SECEV); |
211 | break; |
212 | default: |
213 | ret = -ENOIOCTLCMD; |
214 | break; |
215 | } |
216 | |
217 | return ret; |
218 | } |
219 | |
220 | /* |
221 | * Provide additional RTC information in /proc/driver/rtc |
222 | */ |
223 | static int at91_rtc_proc(struct device *dev, struct seq_file *seq) |
224 | { |
225 | unsigned long imr = at91_sys_read(AT91_RTC_IMR); |
226 | |
227 | seq_printf(seq, "update_IRQ\t: %s\n", |
228 | (imr & AT91_RTC_ACKUPD) ? "yes" : "no"); |
229 | seq_printf(seq, "periodic_IRQ\t: %s\n", |
230 | (imr & AT91_RTC_SECEV) ? "yes" : "no"); |
231 | |
232 | return 0; |
233 | } |
234 | |
235 | /* |
236 | * IRQ handler for the RTC |
237 | */ |
238 | static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id) |
239 | { |
240 | struct platform_device *pdev = dev_id; |
241 | struct rtc_device *rtc = platform_get_drvdata(pdev); |
242 | unsigned int rtsr; |
243 | unsigned long events = 0; |
244 | |
245 | rtsr = at91_sys_read(AT91_RTC_SR) & at91_sys_read(AT91_RTC_IMR); |
246 | if (rtsr) { /* this interrupt is shared! Is it ours? */ |
247 | if (rtsr & AT91_RTC_ALARM) |
248 | events |= (RTC_AF | RTC_IRQF); |
249 | if (rtsr & AT91_RTC_SECEV) |
250 | events |= (RTC_UF | RTC_IRQF); |
251 | if (rtsr & AT91_RTC_ACKUPD) |
252 | complete(&at91_rtc_updated); |
253 | |
254 | at91_sys_write(AT91_RTC_SCCR, rtsr); /* clear status reg */ |
255 | |
256 | rtc_update_irq(rtc, 1, events); |
257 | |
258 | pr_debug("%s(): num=%ld, events=0x%02lx\n", __func__, |
259 | events >> 8, events & 0x000000FF); |
260 | |
261 | return IRQ_HANDLED; |
262 | } |
263 | return IRQ_NONE; /* not handled */ |
264 | } |
265 | |
266 | static const struct rtc_class_ops at91_rtc_ops = { |
267 | .ioctl = at91_rtc_ioctl, |
268 | .read_time = at91_rtc_readtime, |
269 | .set_time = at91_rtc_settime, |
270 | .read_alarm = at91_rtc_readalarm, |
271 | .set_alarm = at91_rtc_setalarm, |
272 | .proc = at91_rtc_proc, |
273 | }; |
274 | |
275 | /* |
276 | * Initialize and install RTC driver |
277 | */ |
278 | static int __init at91_rtc_probe(struct platform_device *pdev) |
279 | { |
280 | struct rtc_device *rtc; |
281 | int ret; |
282 | |
283 | at91_sys_write(AT91_RTC_CR, 0); |
284 | at91_sys_write(AT91_RTC_MR, 0); /* 24 hour mode */ |
285 | |
286 | /* Disable all interrupts */ |
287 | at91_sys_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM | |
288 | AT91_RTC_SECEV | AT91_RTC_TIMEV | |
289 | AT91_RTC_CALEV); |
290 | |
291 | ret = request_irq(AT91_ID_SYS, at91_rtc_interrupt, |
292 | IRQF_SHARED, |
293 | "at91_rtc", pdev); |
294 | if (ret) { |
295 | printk(KERN_ERR "at91_rtc: IRQ %d already in use.\n", |
296 | AT91_ID_SYS); |
297 | return ret; |
298 | } |
299 | |
300 | /* cpu init code should really have flagged this device as |
301 | * being wake-capable; if it didn't, do that here. |
302 | */ |
303 | if (!device_can_wakeup(&pdev->dev)) |
304 | device_init_wakeup(&pdev->dev, 1); |
305 | |
306 | rtc = rtc_device_register(pdev->name, &pdev->dev, |
307 | &at91_rtc_ops, THIS_MODULE); |
308 | if (IS_ERR(rtc)) { |
309 | free_irq(AT91_ID_SYS, pdev); |
310 | return PTR_ERR(rtc); |
311 | } |
312 | platform_set_drvdata(pdev, rtc); |
313 | |
314 | printk(KERN_INFO "AT91 Real Time Clock driver.\n"); |
315 | return 0; |
316 | } |
317 | |
318 | /* |
319 | * Disable and remove the RTC driver |
320 | */ |
321 | static int __exit at91_rtc_remove(struct platform_device *pdev) |
322 | { |
323 | struct rtc_device *rtc = platform_get_drvdata(pdev); |
324 | |
325 | /* Disable all interrupts */ |
326 | at91_sys_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM | |
327 | AT91_RTC_SECEV | AT91_RTC_TIMEV | |
328 | AT91_RTC_CALEV); |
329 | free_irq(AT91_ID_SYS, pdev); |
330 | |
331 | rtc_device_unregister(rtc); |
332 | platform_set_drvdata(pdev, NULL); |
333 | |
334 | return 0; |
335 | } |
336 | |
337 | #ifdef CONFIG_PM |
338 | |
339 | /* AT91RM9200 RTC Power management control */ |
340 | |
341 | static u32 at91_rtc_imr; |
342 | |
343 | static int at91_rtc_suspend(struct device *dev) |
344 | { |
345 | /* this IRQ is shared with DBGU and other hardware which isn't |
346 | * necessarily doing PM like we are... |
347 | */ |
348 | at91_rtc_imr = at91_sys_read(AT91_RTC_IMR) |
349 | & (AT91_RTC_ALARM|AT91_RTC_SECEV); |
350 | if (at91_rtc_imr) { |
351 | if (device_may_wakeup(dev)) |
352 | enable_irq_wake(AT91_ID_SYS); |
353 | else |
354 | at91_sys_write(AT91_RTC_IDR, at91_rtc_imr); |
355 | } |
356 | return 0; |
357 | } |
358 | |
359 | static int at91_rtc_resume(struct device *dev) |
360 | { |
361 | if (at91_rtc_imr) { |
362 | if (device_may_wakeup(dev)) |
363 | disable_irq_wake(AT91_ID_SYS); |
364 | else |
365 | at91_sys_write(AT91_RTC_IER, at91_rtc_imr); |
366 | } |
367 | return 0; |
368 | } |
369 | |
370 | static const struct dev_pm_ops at91_rtc_pm = { |
371 | .suspend = at91_rtc_suspend, |
372 | .resume = at91_rtc_resume, |
373 | }; |
374 | |
375 | #define at91_rtc_pm_ptr &at91_rtc_pm |
376 | |
377 | #else |
378 | #define at91_rtc_pm_ptr NULL |
379 | #endif |
380 | |
381 | static struct platform_driver at91_rtc_driver = { |
382 | .remove = __exit_p(at91_rtc_remove), |
383 | .driver = { |
384 | .name = "at91_rtc", |
385 | .owner = THIS_MODULE, |
386 | .pm = at91_rtc_pm_ptr, |
387 | }, |
388 | }; |
389 | |
390 | static int __init at91_rtc_init(void) |
391 | { |
392 | return platform_driver_probe(&at91_rtc_driver, at91_rtc_probe); |
393 | } |
394 | |
395 | static void __exit at91_rtc_exit(void) |
396 | { |
397 | platform_driver_unregister(&at91_rtc_driver); |
398 | } |
399 | |
400 | module_init(at91_rtc_init); |
401 | module_exit(at91_rtc_exit); |
402 | |
403 | MODULE_AUTHOR("Rick Bronson"); |
404 | MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200"); |
405 | MODULE_LICENSE("GPL"); |
406 | MODULE_ALIAS("platform:at91_rtc"); |
407 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9