[RTC] remove references to asm/mach/time.h
[linux-2.6.git] / drivers / rtc / rtc-omap.c
1 /*
2  * TI OMAP1 Real Time Clock interface for Linux
3  *
4  * Copyright (C) 2003 MontaVista Software, Inc.
5  * Author: George G. Davis <gdavis@mvista.com> or <source@mvista.com>
6  *
7  * Copyright (C) 2006 David Brownell (new RTC framework)
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License
11  * as published by the Free Software Foundation; either version
12  * 2 of the License, or (at your option) any later version.
13  */
14
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/ioport.h>
19 #include <linux/delay.h>
20 #include <linux/rtc.h>
21 #include <linux/bcd.h>
22 #include <linux/platform_device.h>
23
24 #include <asm/io.h>
25
26
27 /* The OMAP1 RTC is a year/month/day/hours/minutes/seconds BCD clock
28  * with century-range alarm matching, driven by the 32kHz clock.
29  *
30  * The main user-visible ways it differs from PC RTCs are by omitting
31  * "don't care" alarm fields and sub-second periodic IRQs, and having
32  * an autoadjust mechanism to calibrate to the true oscillator rate.
33  *
34  * Board-specific wiring options include using split power mode with
35  * RTC_OFF_NOFF used as the reset signal (so the RTC won't be reset),
36  * and wiring RTC_WAKE_INT (so the RTC alarm can wake the system from
37  * low power modes).  See the BOARD-SPECIFIC CUSTOMIZATION comment.
38  */
39
40 #define OMAP_RTC_BASE                   0xfffb4800
41
42 /* RTC registers */
43 #define OMAP_RTC_SECONDS_REG            0x00
44 #define OMAP_RTC_MINUTES_REG            0x04
45 #define OMAP_RTC_HOURS_REG              0x08
46 #define OMAP_RTC_DAYS_REG               0x0C
47 #define OMAP_RTC_MONTHS_REG             0x10
48 #define OMAP_RTC_YEARS_REG              0x14
49 #define OMAP_RTC_WEEKS_REG              0x18
50
51 #define OMAP_RTC_ALARM_SECONDS_REG      0x20
52 #define OMAP_RTC_ALARM_MINUTES_REG      0x24
53 #define OMAP_RTC_ALARM_HOURS_REG        0x28
54 #define OMAP_RTC_ALARM_DAYS_REG         0x2c
55 #define OMAP_RTC_ALARM_MONTHS_REG       0x30
56 #define OMAP_RTC_ALARM_YEARS_REG        0x34
57
58 #define OMAP_RTC_CTRL_REG               0x40
59 #define OMAP_RTC_STATUS_REG             0x44
60 #define OMAP_RTC_INTERRUPTS_REG         0x48
61
62 #define OMAP_RTC_COMP_LSB_REG           0x4c
63 #define OMAP_RTC_COMP_MSB_REG           0x50
64 #define OMAP_RTC_OSC_REG                0x54
65
66 /* OMAP_RTC_CTRL_REG bit fields: */
67 #define OMAP_RTC_CTRL_SPLIT             (1<<7)
68 #define OMAP_RTC_CTRL_DISABLE           (1<<6)
69 #define OMAP_RTC_CTRL_SET_32_COUNTER    (1<<5)
70 #define OMAP_RTC_CTRL_TEST              (1<<4)
71 #define OMAP_RTC_CTRL_MODE_12_24        (1<<3)
72 #define OMAP_RTC_CTRL_AUTO_COMP         (1<<2)
73 #define OMAP_RTC_CTRL_ROUND_30S         (1<<1)
74 #define OMAP_RTC_CTRL_STOP              (1<<0)
75
76 /* OMAP_RTC_STATUS_REG bit fields: */
77 #define OMAP_RTC_STATUS_POWER_UP        (1<<7)
78 #define OMAP_RTC_STATUS_ALARM           (1<<6)
79 #define OMAP_RTC_STATUS_1D_EVENT        (1<<5)
80 #define OMAP_RTC_STATUS_1H_EVENT        (1<<4)
81 #define OMAP_RTC_STATUS_1M_EVENT        (1<<3)
82 #define OMAP_RTC_STATUS_1S_EVENT        (1<<2)
83 #define OMAP_RTC_STATUS_RUN             (1<<1)
84 #define OMAP_RTC_STATUS_BUSY            (1<<0)
85
86 /* OMAP_RTC_INTERRUPTS_REG bit fields: */
87 #define OMAP_RTC_INTERRUPTS_IT_ALARM    (1<<3)
88 #define OMAP_RTC_INTERRUPTS_IT_TIMER    (1<<2)
89
90
91 #define rtc_read(addr)          omap_readb(OMAP_RTC_BASE + (addr))
92 #define rtc_write(val, addr)    omap_writeb(val, OMAP_RTC_BASE + (addr))
93
94
95 /* platform_bus isn't hotpluggable, so for static linkage it'd be safe
96  * to get rid of probe() and remove() code ... too bad the driver struct
97  * remembers probe(), that's about 25% of the runtime footprint!!
98  */
99 #ifndef MODULE
100 #undef  __devexit
101 #undef  __devexit_p
102 #define __devexit       __exit
103 #define __devexit_p     __exit_p
104 #endif
105
106
107 /* we rely on the rtc framework to handle locking (rtc->ops_lock),
108  * so the only other requirement is that register accesses which
109  * require BUSY to be clear are made with IRQs locally disabled
110  */
111 static void rtc_wait_not_busy(void)
112 {
113         int     count = 0;
114         u8      status;
115
116         /* BUSY may stay active for 1/32768 second (~30 usec) */
117         for (count = 0; count < 50; count++) {
118                 status = rtc_read(OMAP_RTC_STATUS_REG);
119                 if ((status & (u8)OMAP_RTC_STATUS_BUSY) == 0)
120                         break;
121                 udelay(1);
122         }
123         /* now we have ~15 usec to read/write various registers */
124 }
125
126 static irqreturn_t rtc_irq(int irq, void *rtc)
127 {
128         unsigned long           events = 0;
129         u8                      irq_data;
130
131         irq_data = rtc_read(OMAP_RTC_STATUS_REG);
132
133         /* alarm irq? */
134         if (irq_data & OMAP_RTC_STATUS_ALARM) {
135                 rtc_write(OMAP_RTC_STATUS_ALARM, OMAP_RTC_STATUS_REG);
136                 events |= RTC_IRQF | RTC_AF;
137         }
138
139         /* 1/sec periodic/update irq? */
140         if (irq_data & OMAP_RTC_STATUS_1S_EVENT)
141                 events |= RTC_IRQF | RTC_UF;
142
143         rtc_update_irq(rtc, 1, events);
144
145         return IRQ_HANDLED;
146 }
147
148 #ifdef  CONFIG_RTC_INTF_DEV
149
150 static int
151 omap_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
152 {
153         u8 reg;
154
155         switch (cmd) {
156         case RTC_AIE_OFF:
157         case RTC_AIE_ON:
158         case RTC_UIE_OFF:
159         case RTC_UIE_ON:
160                 break;
161         default:
162                 return -ENOIOCTLCMD;
163         }
164
165         local_irq_disable();
166         rtc_wait_not_busy();
167         reg = rtc_read(OMAP_RTC_INTERRUPTS_REG);
168         switch (cmd) {
169         /* AIE = Alarm Interrupt Enable */
170         case RTC_AIE_OFF:
171                 reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
172                 break;
173         case RTC_AIE_ON:
174                 reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
175                 break;
176         /* UIE = Update Interrupt Enable (1/second) */
177         case RTC_UIE_OFF:
178                 reg &= ~OMAP_RTC_INTERRUPTS_IT_TIMER;
179                 break;
180         case RTC_UIE_ON:
181                 reg |= OMAP_RTC_INTERRUPTS_IT_TIMER;
182                 break;
183         }
184         rtc_wait_not_busy();
185         rtc_write(reg, OMAP_RTC_INTERRUPTS_REG);
186         local_irq_enable();
187
188         return 0;
189 }
190
191 #else
192 #define omap_rtc_ioctl  NULL
193 #endif
194
195 /* this hardware doesn't support "don't care" alarm fields */
196 static int tm2bcd(struct rtc_time *tm)
197 {
198         if (rtc_valid_tm(tm) != 0)
199                 return -EINVAL;
200
201         tm->tm_sec = BIN2BCD(tm->tm_sec);
202         tm->tm_min = BIN2BCD(tm->tm_min);
203         tm->tm_hour = BIN2BCD(tm->tm_hour);
204         tm->tm_mday = BIN2BCD(tm->tm_mday);
205
206         tm->tm_mon = BIN2BCD(tm->tm_mon + 1);
207
208         /* epoch == 1900 */
209         if (tm->tm_year < 100 || tm->tm_year > 199)
210                 return -EINVAL;
211         tm->tm_year = BIN2BCD(tm->tm_year - 100);
212
213         return 0;
214 }
215
216 static void bcd2tm(struct rtc_time *tm)
217 {
218         tm->tm_sec = BCD2BIN(tm->tm_sec);
219         tm->tm_min = BCD2BIN(tm->tm_min);
220         tm->tm_hour = BCD2BIN(tm->tm_hour);
221         tm->tm_mday = BCD2BIN(tm->tm_mday);
222         tm->tm_mon = BCD2BIN(tm->tm_mon) - 1;
223         /* epoch == 1900 */
224         tm->tm_year = BCD2BIN(tm->tm_year) + 100;
225 }
226
227
228 static int omap_rtc_read_time(struct device *dev, struct rtc_time *tm)
229 {
230         /* we don't report wday/yday/isdst ... */
231         local_irq_disable();
232         rtc_wait_not_busy();
233
234         tm->tm_sec = rtc_read(OMAP_RTC_SECONDS_REG);
235         tm->tm_min = rtc_read(OMAP_RTC_MINUTES_REG);
236         tm->tm_hour = rtc_read(OMAP_RTC_HOURS_REG);
237         tm->tm_mday = rtc_read(OMAP_RTC_DAYS_REG);
238         tm->tm_mon = rtc_read(OMAP_RTC_MONTHS_REG);
239         tm->tm_year = rtc_read(OMAP_RTC_YEARS_REG);
240
241         local_irq_enable();
242
243         bcd2tm(tm);
244         return 0;
245 }
246
247 static int omap_rtc_set_time(struct device *dev, struct rtc_time *tm)
248 {
249         if (tm2bcd(tm) < 0)
250                 return -EINVAL;
251         local_irq_disable();
252         rtc_wait_not_busy();
253
254         rtc_write(tm->tm_year, OMAP_RTC_YEARS_REG);
255         rtc_write(tm->tm_mon, OMAP_RTC_MONTHS_REG);
256         rtc_write(tm->tm_mday, OMAP_RTC_DAYS_REG);
257         rtc_write(tm->tm_hour, OMAP_RTC_HOURS_REG);
258         rtc_write(tm->tm_min, OMAP_RTC_MINUTES_REG);
259         rtc_write(tm->tm_sec, OMAP_RTC_SECONDS_REG);
260
261         local_irq_enable();
262
263         return 0;
264 }
265
266 static int omap_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
267 {
268         local_irq_disable();
269         rtc_wait_not_busy();
270
271         alm->time.tm_sec = rtc_read(OMAP_RTC_ALARM_SECONDS_REG);
272         alm->time.tm_min = rtc_read(OMAP_RTC_ALARM_MINUTES_REG);
273         alm->time.tm_hour = rtc_read(OMAP_RTC_ALARM_HOURS_REG);
274         alm->time.tm_mday = rtc_read(OMAP_RTC_ALARM_DAYS_REG);
275         alm->time.tm_mon = rtc_read(OMAP_RTC_ALARM_MONTHS_REG);
276         alm->time.tm_year = rtc_read(OMAP_RTC_ALARM_YEARS_REG);
277
278         local_irq_enable();
279
280         bcd2tm(&alm->time);
281         alm->enabled = !!(rtc_read(OMAP_RTC_INTERRUPTS_REG)
282                         & OMAP_RTC_INTERRUPTS_IT_ALARM);
283
284         return 0;
285 }
286
287 static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
288 {
289         u8 reg;
290
291         if (tm2bcd(&alm->time) < 0)
292                 return -EINVAL;
293
294         local_irq_disable();
295         rtc_wait_not_busy();
296
297         rtc_write(alm->time.tm_year, OMAP_RTC_ALARM_YEARS_REG);
298         rtc_write(alm->time.tm_mon, OMAP_RTC_ALARM_MONTHS_REG);
299         rtc_write(alm->time.tm_mday, OMAP_RTC_ALARM_DAYS_REG);
300         rtc_write(alm->time.tm_hour, OMAP_RTC_ALARM_HOURS_REG);
301         rtc_write(alm->time.tm_min, OMAP_RTC_ALARM_MINUTES_REG);
302         rtc_write(alm->time.tm_sec, OMAP_RTC_ALARM_SECONDS_REG);
303
304         reg = rtc_read(OMAP_RTC_INTERRUPTS_REG);
305         if (alm->enabled)
306                 reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
307         else
308                 reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
309         rtc_write(reg, OMAP_RTC_INTERRUPTS_REG);
310
311         local_irq_enable();
312
313         return 0;
314 }
315
316 static struct rtc_class_ops omap_rtc_ops = {
317         .ioctl          = omap_rtc_ioctl,
318         .read_time      = omap_rtc_read_time,
319         .set_time       = omap_rtc_set_time,
320         .read_alarm     = omap_rtc_read_alarm,
321         .set_alarm      = omap_rtc_set_alarm,
322 };
323
324 static int omap_rtc_alarm;
325 static int omap_rtc_timer;
326
327 static int __devinit omap_rtc_probe(struct platform_device *pdev)
328 {
329         struct resource         *res, *mem;
330         struct rtc_device       *rtc;
331         u8                      reg, new_ctrl;
332
333         omap_rtc_timer = platform_get_irq(pdev, 0);
334         if (omap_rtc_timer <= 0) {
335                 pr_debug("%s: no update irq?\n", pdev->name);
336                 return -ENOENT;
337         }
338
339         omap_rtc_alarm = platform_get_irq(pdev, 1);
340         if (omap_rtc_alarm <= 0) {
341                 pr_debug("%s: no alarm irq?\n", pdev->name);
342                 return -ENOENT;
343         }
344
345         /* NOTE:  using static mapping for RTC registers */
346         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
347         if (res && res->start != OMAP_RTC_BASE) {
348                 pr_debug("%s: RTC registers at %08x, expected %08x\n",
349                         pdev->name, (unsigned) res->start, OMAP_RTC_BASE);
350                 return -ENOENT;
351         }
352
353         if (res)
354                 mem = request_mem_region(res->start,
355                                 res->end - res->start + 1,
356                                 pdev->name);
357         else
358                 mem = NULL;
359         if (!mem) {
360                 pr_debug("%s: RTC registers at %08x are not free\n",
361                         pdev->name, OMAP_RTC_BASE);
362                 return -EBUSY;
363         }
364
365         rtc = rtc_device_register(pdev->name, &pdev->dev,
366                         &omap_rtc_ops, THIS_MODULE);
367         if (IS_ERR(rtc)) {
368                 pr_debug("%s: can't register RTC device, err %ld\n",
369                         pdev->name, PTR_ERR(rtc));
370                 goto fail;
371         }
372         platform_set_drvdata(pdev, rtc);
373         dev_set_drvdata(&rtc->dev, mem);
374
375         /* clear pending irqs, and set 1/second periodic,
376          * which we'll use instead of update irqs
377          */
378         rtc_write(0, OMAP_RTC_INTERRUPTS_REG);
379
380         /* clear old status */
381         reg = rtc_read(OMAP_RTC_STATUS_REG);
382         if (reg & (u8) OMAP_RTC_STATUS_POWER_UP) {
383                 pr_info("%s: RTC power up reset detected\n",
384                         pdev->name);
385                 rtc_write(OMAP_RTC_STATUS_POWER_UP, OMAP_RTC_STATUS_REG);
386         }
387         if (reg & (u8) OMAP_RTC_STATUS_ALARM)
388                 rtc_write(OMAP_RTC_STATUS_ALARM, OMAP_RTC_STATUS_REG);
389
390         /* handle periodic and alarm irqs */
391         if (request_irq(omap_rtc_timer, rtc_irq, IRQF_DISABLED,
392                         rtc->dev.bus_id, rtc)) {
393                 pr_debug("%s: RTC timer interrupt IRQ%d already claimed\n",
394                         pdev->name, omap_rtc_timer);
395                 goto fail0;
396         }
397         if (request_irq(omap_rtc_alarm, rtc_irq, IRQF_DISABLED,
398                         rtc->dev.bus_id, rtc)) {
399                 pr_debug("%s: RTC alarm interrupt IRQ%d already claimed\n",
400                         pdev->name, omap_rtc_alarm);
401                 goto fail1;
402         }
403
404         /* On boards with split power, RTC_ON_NOFF won't reset the RTC */
405         reg = rtc_read(OMAP_RTC_CTRL_REG);
406         if (reg & (u8) OMAP_RTC_CTRL_STOP)
407                 pr_info("%s: already running\n", pdev->name);
408
409         /* force to 24 hour mode */
410         new_ctrl = reg & ~(OMAP_RTC_CTRL_SPLIT|OMAP_RTC_CTRL_AUTO_COMP);
411         new_ctrl |= OMAP_RTC_CTRL_STOP;
412
413         /* BOARD-SPECIFIC CUSTOMIZATION CAN GO HERE:
414          *
415          *  - Boards wired so that RTC_WAKE_INT does something, and muxed
416          *    right (W13_1610_RTC_WAKE_INT is the default after chip reset),
417          *    should initialize the device wakeup flag appropriately.
418          *
419          *  - Boards wired so RTC_ON_nOFF is used as the reset signal,
420          *    rather than nPWRON_RESET, should forcibly enable split
421          *    power mode.  (Some chip errata report that RTC_CTRL_SPLIT
422          *    is write-only, and always reads as zero...)
423          */
424         device_init_wakeup(&pdev->dev, 0);
425
426         if (new_ctrl & (u8) OMAP_RTC_CTRL_SPLIT)
427                 pr_info("%s: split power mode\n", pdev->name);
428
429         if (reg != new_ctrl)
430                 rtc_write(new_ctrl, OMAP_RTC_CTRL_REG);
431
432         return 0;
433
434 fail1:
435         free_irq(omap_rtc_timer, NULL);
436 fail0:
437         rtc_device_unregister(rtc);
438 fail:
439         release_resource(mem);
440         return -EIO;
441 }
442
443 static int __devexit omap_rtc_remove(struct platform_device *pdev)
444 {
445         struct rtc_device       *rtc = platform_get_drvdata(pdev);;
446
447         device_init_wakeup(&pdev->dev, 0);
448
449         /* leave rtc running, but disable irqs */
450         rtc_write(0, OMAP_RTC_INTERRUPTS_REG);
451
452         free_irq(omap_rtc_timer, rtc);
453         free_irq(omap_rtc_alarm, rtc);
454
455         release_resource(dev_get_drvdata(&rtc->dev));
456         rtc_device_unregister(rtc);
457         return 0;
458 }
459
460 #ifdef CONFIG_PM
461
462 static u8 irqstat;
463
464 static int omap_rtc_suspend(struct platform_device *pdev, pm_message_t state)
465 {
466         irqstat = rtc_read(OMAP_RTC_INTERRUPTS_REG);
467
468         /* FIXME the RTC alarm is not currently acting as a wakeup event
469          * source, and in fact this enable() call is just saving a flag
470          * that's never used...
471          */
472         if (device_may_wakeup(&pdev->dev))
473                 enable_irq_wake(omap_rtc_alarm);
474         else
475                 rtc_write(0, OMAP_RTC_INTERRUPTS_REG);
476
477         return 0;
478 }
479
480 static int omap_rtc_resume(struct platform_device *pdev)
481 {
482         if (device_may_wakeup(&pdev->dev))
483                 disable_irq_wake(omap_rtc_alarm);
484         else
485                 rtc_write(irqstat, OMAP_RTC_INTERRUPTS_REG);
486         return 0;
487 }
488
489 #else
490 #define omap_rtc_suspend NULL
491 #define omap_rtc_resume  NULL
492 #endif
493
494 static void omap_rtc_shutdown(struct platform_device *pdev)
495 {
496         rtc_write(0, OMAP_RTC_INTERRUPTS_REG);
497 }
498
499 MODULE_ALIAS("platform:omap_rtc");
500 static struct platform_driver omap_rtc_driver = {
501         .probe          = omap_rtc_probe,
502         .remove         = __devexit_p(omap_rtc_remove),
503         .suspend        = omap_rtc_suspend,
504         .resume         = omap_rtc_resume,
505         .shutdown       = omap_rtc_shutdown,
506         .driver         = {
507                 .name   = "omap_rtc",
508                 .owner  = THIS_MODULE,
509         },
510 };
511
512 static int __init rtc_init(void)
513 {
514         return platform_driver_register(&omap_rtc_driver);
515 }
516 module_init(rtc_init);
517
518 static void __exit rtc_exit(void)
519 {
520         platform_driver_unregister(&omap_rtc_driver);
521 }
522 module_exit(rtc_exit);
523
524 MODULE_AUTHOR("George G. Davis (and others)");
525 MODULE_LICENSE("GPL");