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Merge branch 'drm-tda998x-devel' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into...
[deliverable/linux.git] / drivers / rtc / rtc-omap.c
1 /*
2 * TI OMAP 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 * Copyright (C) 2014 Johan Hovold <johan@kernel.org>
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
14 */
15
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/module.h>
19 #include <linux/ioport.h>
20 #include <linux/delay.h>
21 #include <linux/rtc.h>
22 #include <linux/bcd.h>
23 #include <linux/platform_device.h>
24 #include <linux/of.h>
25 #include <linux/of_device.h>
26 #include <linux/pm_runtime.h>
27 #include <linux/io.h>
28 #include <linux/clk.h>
29
30 /*
31 * The OMAP RTC is a year/month/day/hours/minutes/seconds BCD clock
32 * with century-range alarm matching, driven by the 32kHz clock.
33 *
34 * The main user-visible ways it differs from PC RTCs are by omitting
35 * "don't care" alarm fields and sub-second periodic IRQs, and having
36 * an autoadjust mechanism to calibrate to the true oscillator rate.
37 *
38 * Board-specific wiring options include using split power mode with
39 * RTC_OFF_NOFF used as the reset signal (so the RTC won't be reset),
40 * and wiring RTC_WAKE_INT (so the RTC alarm can wake the system from
41 * low power modes) for OMAP1 boards (OMAP-L138 has this built into
42 * the SoC). See the BOARD-SPECIFIC CUSTOMIZATION comment.
43 */
44
45 /* RTC registers */
46 #define OMAP_RTC_SECONDS_REG 0x00
47 #define OMAP_RTC_MINUTES_REG 0x04
48 #define OMAP_RTC_HOURS_REG 0x08
49 #define OMAP_RTC_DAYS_REG 0x0C
50 #define OMAP_RTC_MONTHS_REG 0x10
51 #define OMAP_RTC_YEARS_REG 0x14
52 #define OMAP_RTC_WEEKS_REG 0x18
53
54 #define OMAP_RTC_ALARM_SECONDS_REG 0x20
55 #define OMAP_RTC_ALARM_MINUTES_REG 0x24
56 #define OMAP_RTC_ALARM_HOURS_REG 0x28
57 #define OMAP_RTC_ALARM_DAYS_REG 0x2c
58 #define OMAP_RTC_ALARM_MONTHS_REG 0x30
59 #define OMAP_RTC_ALARM_YEARS_REG 0x34
60
61 #define OMAP_RTC_CTRL_REG 0x40
62 #define OMAP_RTC_STATUS_REG 0x44
63 #define OMAP_RTC_INTERRUPTS_REG 0x48
64
65 #define OMAP_RTC_COMP_LSB_REG 0x4c
66 #define OMAP_RTC_COMP_MSB_REG 0x50
67 #define OMAP_RTC_OSC_REG 0x54
68
69 #define OMAP_RTC_KICK0_REG 0x6c
70 #define OMAP_RTC_KICK1_REG 0x70
71
72 #define OMAP_RTC_IRQWAKEEN 0x7c
73
74 #define OMAP_RTC_ALARM2_SECONDS_REG 0x80
75 #define OMAP_RTC_ALARM2_MINUTES_REG 0x84
76 #define OMAP_RTC_ALARM2_HOURS_REG 0x88
77 #define OMAP_RTC_ALARM2_DAYS_REG 0x8c
78 #define OMAP_RTC_ALARM2_MONTHS_REG 0x90
79 #define OMAP_RTC_ALARM2_YEARS_REG 0x94
80
81 #define OMAP_RTC_PMIC_REG 0x98
82
83 /* OMAP_RTC_CTRL_REG bit fields: */
84 #define OMAP_RTC_CTRL_SPLIT BIT(7)
85 #define OMAP_RTC_CTRL_DISABLE BIT(6)
86 #define OMAP_RTC_CTRL_SET_32_COUNTER BIT(5)
87 #define OMAP_RTC_CTRL_TEST BIT(4)
88 #define OMAP_RTC_CTRL_MODE_12_24 BIT(3)
89 #define OMAP_RTC_CTRL_AUTO_COMP BIT(2)
90 #define OMAP_RTC_CTRL_ROUND_30S BIT(1)
91 #define OMAP_RTC_CTRL_STOP BIT(0)
92
93 /* OMAP_RTC_STATUS_REG bit fields: */
94 #define OMAP_RTC_STATUS_POWER_UP BIT(7)
95 #define OMAP_RTC_STATUS_ALARM2 BIT(7)
96 #define OMAP_RTC_STATUS_ALARM BIT(6)
97 #define OMAP_RTC_STATUS_1D_EVENT BIT(5)
98 #define OMAP_RTC_STATUS_1H_EVENT BIT(4)
99 #define OMAP_RTC_STATUS_1M_EVENT BIT(3)
100 #define OMAP_RTC_STATUS_1S_EVENT BIT(2)
101 #define OMAP_RTC_STATUS_RUN BIT(1)
102 #define OMAP_RTC_STATUS_BUSY BIT(0)
103
104 /* OMAP_RTC_INTERRUPTS_REG bit fields: */
105 #define OMAP_RTC_INTERRUPTS_IT_ALARM2 BIT(4)
106 #define OMAP_RTC_INTERRUPTS_IT_ALARM BIT(3)
107 #define OMAP_RTC_INTERRUPTS_IT_TIMER BIT(2)
108
109 /* OMAP_RTC_OSC_REG bit fields: */
110 #define OMAP_RTC_OSC_32KCLK_EN BIT(6)
111 #define OMAP_RTC_OSC_SEL_32KCLK_SRC BIT(3)
112
113 /* OMAP_RTC_IRQWAKEEN bit fields: */
114 #define OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN BIT(1)
115
116 /* OMAP_RTC_PMIC bit fields: */
117 #define OMAP_RTC_PMIC_POWER_EN_EN BIT(16)
118
119 /* OMAP_RTC_KICKER values */
120 #define KICK0_VALUE 0x83e70b13
121 #define KICK1_VALUE 0x95a4f1e0
122
123 struct omap_rtc;
124
125 struct omap_rtc_device_type {
126 bool has_32kclk_en;
127 bool has_irqwakeen;
128 bool has_pmic_mode;
129 bool has_power_up_reset;
130 void (*lock)(struct omap_rtc *rtc);
131 void (*unlock)(struct omap_rtc *rtc);
132 };
133
134 struct omap_rtc {
135 struct rtc_device *rtc;
136 void __iomem *base;
137 struct clk *clk;
138 int irq_alarm;
139 int irq_timer;
140 u8 interrupts_reg;
141 bool is_pmic_controller;
142 bool has_ext_clk;
143 const struct omap_rtc_device_type *type;
144 };
145
146 static inline u8 rtc_read(struct omap_rtc *rtc, unsigned int reg)
147 {
148 return readb(rtc->base + reg);
149 }
150
151 static inline u32 rtc_readl(struct omap_rtc *rtc, unsigned int reg)
152 {
153 return readl(rtc->base + reg);
154 }
155
156 static inline void rtc_write(struct omap_rtc *rtc, unsigned int reg, u8 val)
157 {
158 writeb(val, rtc->base + reg);
159 }
160
161 static inline void rtc_writel(struct omap_rtc *rtc, unsigned int reg, u32 val)
162 {
163 writel(val, rtc->base + reg);
164 }
165
166 static void am3352_rtc_unlock(struct omap_rtc *rtc)
167 {
168 rtc_writel(rtc, OMAP_RTC_KICK0_REG, KICK0_VALUE);
169 rtc_writel(rtc, OMAP_RTC_KICK1_REG, KICK1_VALUE);
170 }
171
172 static void am3352_rtc_lock(struct omap_rtc *rtc)
173 {
174 rtc_writel(rtc, OMAP_RTC_KICK0_REG, 0);
175 rtc_writel(rtc, OMAP_RTC_KICK1_REG, 0);
176 }
177
178 static void default_rtc_unlock(struct omap_rtc *rtc)
179 {
180 }
181
182 static void default_rtc_lock(struct omap_rtc *rtc)
183 {
184 }
185
186 /*
187 * We rely on the rtc framework to handle locking (rtc->ops_lock),
188 * so the only other requirement is that register accesses which
189 * require BUSY to be clear are made with IRQs locally disabled
190 */
191 static void rtc_wait_not_busy(struct omap_rtc *rtc)
192 {
193 int count;
194 u8 status;
195
196 /* BUSY may stay active for 1/32768 second (~30 usec) */
197 for (count = 0; count < 50; count++) {
198 status = rtc_read(rtc, OMAP_RTC_STATUS_REG);
199 if (!(status & OMAP_RTC_STATUS_BUSY))
200 break;
201 udelay(1);
202 }
203 /* now we have ~15 usec to read/write various registers */
204 }
205
206 static irqreturn_t rtc_irq(int irq, void *dev_id)
207 {
208 struct omap_rtc *rtc = dev_id;
209 unsigned long events = 0;
210 u8 irq_data;
211
212 irq_data = rtc_read(rtc, OMAP_RTC_STATUS_REG);
213
214 /* alarm irq? */
215 if (irq_data & OMAP_RTC_STATUS_ALARM) {
216 rtc->type->unlock(rtc);
217 rtc_write(rtc, OMAP_RTC_STATUS_REG, OMAP_RTC_STATUS_ALARM);
218 rtc->type->lock(rtc);
219 events |= RTC_IRQF | RTC_AF;
220 }
221
222 /* 1/sec periodic/update irq? */
223 if (irq_data & OMAP_RTC_STATUS_1S_EVENT)
224 events |= RTC_IRQF | RTC_UF;
225
226 rtc_update_irq(rtc->rtc, 1, events);
227
228 return IRQ_HANDLED;
229 }
230
231 static int omap_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
232 {
233 struct omap_rtc *rtc = dev_get_drvdata(dev);
234 u8 reg, irqwake_reg = 0;
235
236 local_irq_disable();
237 rtc_wait_not_busy(rtc);
238 reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
239 if (rtc->type->has_irqwakeen)
240 irqwake_reg = rtc_read(rtc, OMAP_RTC_IRQWAKEEN);
241
242 if (enabled) {
243 reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
244 irqwake_reg |= OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
245 } else {
246 reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
247 irqwake_reg &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
248 }
249 rtc_wait_not_busy(rtc);
250 rtc->type->unlock(rtc);
251 rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, reg);
252 if (rtc->type->has_irqwakeen)
253 rtc_write(rtc, OMAP_RTC_IRQWAKEEN, irqwake_reg);
254 rtc->type->lock(rtc);
255 local_irq_enable();
256
257 return 0;
258 }
259
260 /* this hardware doesn't support "don't care" alarm fields */
261 static int tm2bcd(struct rtc_time *tm)
262 {
263 if (rtc_valid_tm(tm) != 0)
264 return -EINVAL;
265
266 tm->tm_sec = bin2bcd(tm->tm_sec);
267 tm->tm_min = bin2bcd(tm->tm_min);
268 tm->tm_hour = bin2bcd(tm->tm_hour);
269 tm->tm_mday = bin2bcd(tm->tm_mday);
270
271 tm->tm_mon = bin2bcd(tm->tm_mon + 1);
272
273 /* epoch == 1900 */
274 if (tm->tm_year < 100 || tm->tm_year > 199)
275 return -EINVAL;
276 tm->tm_year = bin2bcd(tm->tm_year - 100);
277
278 return 0;
279 }
280
281 static void bcd2tm(struct rtc_time *tm)
282 {
283 tm->tm_sec = bcd2bin(tm->tm_sec);
284 tm->tm_min = bcd2bin(tm->tm_min);
285 tm->tm_hour = bcd2bin(tm->tm_hour);
286 tm->tm_mday = bcd2bin(tm->tm_mday);
287 tm->tm_mon = bcd2bin(tm->tm_mon) - 1;
288 /* epoch == 1900 */
289 tm->tm_year = bcd2bin(tm->tm_year) + 100;
290 }
291
292 static void omap_rtc_read_time_raw(struct omap_rtc *rtc, struct rtc_time *tm)
293 {
294 tm->tm_sec = rtc_read(rtc, OMAP_RTC_SECONDS_REG);
295 tm->tm_min = rtc_read(rtc, OMAP_RTC_MINUTES_REG);
296 tm->tm_hour = rtc_read(rtc, OMAP_RTC_HOURS_REG);
297 tm->tm_mday = rtc_read(rtc, OMAP_RTC_DAYS_REG);
298 tm->tm_mon = rtc_read(rtc, OMAP_RTC_MONTHS_REG);
299 tm->tm_year = rtc_read(rtc, OMAP_RTC_YEARS_REG);
300 }
301
302 static int omap_rtc_read_time(struct device *dev, struct rtc_time *tm)
303 {
304 struct omap_rtc *rtc = dev_get_drvdata(dev);
305
306 /* we don't report wday/yday/isdst ... */
307 local_irq_disable();
308 rtc_wait_not_busy(rtc);
309 omap_rtc_read_time_raw(rtc, tm);
310 local_irq_enable();
311
312 bcd2tm(tm);
313
314 return 0;
315 }
316
317 static int omap_rtc_set_time(struct device *dev, struct rtc_time *tm)
318 {
319 struct omap_rtc *rtc = dev_get_drvdata(dev);
320
321 if (tm2bcd(tm) < 0)
322 return -EINVAL;
323
324 local_irq_disable();
325 rtc_wait_not_busy(rtc);
326
327 rtc->type->unlock(rtc);
328 rtc_write(rtc, OMAP_RTC_YEARS_REG, tm->tm_year);
329 rtc_write(rtc, OMAP_RTC_MONTHS_REG, tm->tm_mon);
330 rtc_write(rtc, OMAP_RTC_DAYS_REG, tm->tm_mday);
331 rtc_write(rtc, OMAP_RTC_HOURS_REG, tm->tm_hour);
332 rtc_write(rtc, OMAP_RTC_MINUTES_REG, tm->tm_min);
333 rtc_write(rtc, OMAP_RTC_SECONDS_REG, tm->tm_sec);
334 rtc->type->lock(rtc);
335
336 local_irq_enable();
337
338 return 0;
339 }
340
341 static int omap_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
342 {
343 struct omap_rtc *rtc = dev_get_drvdata(dev);
344 u8 interrupts;
345
346 local_irq_disable();
347 rtc_wait_not_busy(rtc);
348
349 alm->time.tm_sec = rtc_read(rtc, OMAP_RTC_ALARM_SECONDS_REG);
350 alm->time.tm_min = rtc_read(rtc, OMAP_RTC_ALARM_MINUTES_REG);
351 alm->time.tm_hour = rtc_read(rtc, OMAP_RTC_ALARM_HOURS_REG);
352 alm->time.tm_mday = rtc_read(rtc, OMAP_RTC_ALARM_DAYS_REG);
353 alm->time.tm_mon = rtc_read(rtc, OMAP_RTC_ALARM_MONTHS_REG);
354 alm->time.tm_year = rtc_read(rtc, OMAP_RTC_ALARM_YEARS_REG);
355
356 local_irq_enable();
357
358 bcd2tm(&alm->time);
359
360 interrupts = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
361 alm->enabled = !!(interrupts & OMAP_RTC_INTERRUPTS_IT_ALARM);
362
363 return 0;
364 }
365
366 static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
367 {
368 struct omap_rtc *rtc = dev_get_drvdata(dev);
369 u8 reg, irqwake_reg = 0;
370
371 if (tm2bcd(&alm->time) < 0)
372 return -EINVAL;
373
374 local_irq_disable();
375 rtc_wait_not_busy(rtc);
376
377 rtc->type->unlock(rtc);
378 rtc_write(rtc, OMAP_RTC_ALARM_YEARS_REG, alm->time.tm_year);
379 rtc_write(rtc, OMAP_RTC_ALARM_MONTHS_REG, alm->time.tm_mon);
380 rtc_write(rtc, OMAP_RTC_ALARM_DAYS_REG, alm->time.tm_mday);
381 rtc_write(rtc, OMAP_RTC_ALARM_HOURS_REG, alm->time.tm_hour);
382 rtc_write(rtc, OMAP_RTC_ALARM_MINUTES_REG, alm->time.tm_min);
383 rtc_write(rtc, OMAP_RTC_ALARM_SECONDS_REG, alm->time.tm_sec);
384
385 reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
386 if (rtc->type->has_irqwakeen)
387 irqwake_reg = rtc_read(rtc, OMAP_RTC_IRQWAKEEN);
388
389 if (alm->enabled) {
390 reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
391 irqwake_reg |= OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
392 } else {
393 reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
394 irqwake_reg &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
395 }
396 rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, reg);
397 if (rtc->type->has_irqwakeen)
398 rtc_write(rtc, OMAP_RTC_IRQWAKEEN, irqwake_reg);
399 rtc->type->lock(rtc);
400
401 local_irq_enable();
402
403 return 0;
404 }
405
406 static struct omap_rtc *omap_rtc_power_off_rtc;
407
408 /*
409 * omap_rtc_poweroff: RTC-controlled power off
410 *
411 * The RTC can be used to control an external PMIC via the pmic_power_en pin,
412 * which can be configured to transition to OFF on ALARM2 events.
413 *
414 * Notes:
415 * The two-second alarm offset is the shortest offset possible as the alarm
416 * registers must be set before the next timer update and the offset
417 * calculation is too heavy for everything to be done within a single access
418 * period (~15 us).
419 *
420 * Called with local interrupts disabled.
421 */
422 static void omap_rtc_power_off(void)
423 {
424 struct omap_rtc *rtc = omap_rtc_power_off_rtc;
425 struct rtc_time tm;
426 unsigned long now;
427 u32 val;
428
429 rtc->type->unlock(rtc);
430 /* enable pmic_power_en control */
431 val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
432 rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN);
433
434 /* set alarm two seconds from now */
435 omap_rtc_read_time_raw(rtc, &tm);
436 bcd2tm(&tm);
437 rtc_tm_to_time(&tm, &now);
438 rtc_time_to_tm(now + 2, &tm);
439
440 if (tm2bcd(&tm) < 0) {
441 dev_err(&rtc->rtc->dev, "power off failed\n");
442 return;
443 }
444
445 rtc_wait_not_busy(rtc);
446
447 rtc_write(rtc, OMAP_RTC_ALARM2_SECONDS_REG, tm.tm_sec);
448 rtc_write(rtc, OMAP_RTC_ALARM2_MINUTES_REG, tm.tm_min);
449 rtc_write(rtc, OMAP_RTC_ALARM2_HOURS_REG, tm.tm_hour);
450 rtc_write(rtc, OMAP_RTC_ALARM2_DAYS_REG, tm.tm_mday);
451 rtc_write(rtc, OMAP_RTC_ALARM2_MONTHS_REG, tm.tm_mon);
452 rtc_write(rtc, OMAP_RTC_ALARM2_YEARS_REG, tm.tm_year);
453
454 /*
455 * enable ALARM2 interrupt
456 *
457 * NOTE: this fails on AM3352 if rtc_write (writeb) is used
458 */
459 val = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
460 rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG,
461 val | OMAP_RTC_INTERRUPTS_IT_ALARM2);
462 rtc->type->lock(rtc);
463
464 /*
465 * Wait for alarm to trigger (within two seconds) and external PMIC to
466 * power off the system. Add a 500 ms margin for external latencies
467 * (e.g. debounce circuits).
468 */
469 mdelay(2500);
470 }
471
472 static struct rtc_class_ops omap_rtc_ops = {
473 .read_time = omap_rtc_read_time,
474 .set_time = omap_rtc_set_time,
475 .read_alarm = omap_rtc_read_alarm,
476 .set_alarm = omap_rtc_set_alarm,
477 .alarm_irq_enable = omap_rtc_alarm_irq_enable,
478 };
479
480 static const struct omap_rtc_device_type omap_rtc_default_type = {
481 .has_power_up_reset = true,
482 .lock = default_rtc_lock,
483 .unlock = default_rtc_unlock,
484 };
485
486 static const struct omap_rtc_device_type omap_rtc_am3352_type = {
487 .has_32kclk_en = true,
488 .has_irqwakeen = true,
489 .has_pmic_mode = true,
490 .lock = am3352_rtc_lock,
491 .unlock = am3352_rtc_unlock,
492 };
493
494 static const struct omap_rtc_device_type omap_rtc_da830_type = {
495 .lock = am3352_rtc_lock,
496 .unlock = am3352_rtc_unlock,
497 };
498
499 static const struct platform_device_id omap_rtc_id_table[] = {
500 {
501 .name = "omap_rtc",
502 .driver_data = (kernel_ulong_t)&omap_rtc_default_type,
503 }, {
504 .name = "am3352-rtc",
505 .driver_data = (kernel_ulong_t)&omap_rtc_am3352_type,
506 }, {
507 .name = "da830-rtc",
508 .driver_data = (kernel_ulong_t)&omap_rtc_da830_type,
509 }, {
510 /* sentinel */
511 }
512 };
513 MODULE_DEVICE_TABLE(platform, omap_rtc_id_table);
514
515 static const struct of_device_id omap_rtc_of_match[] = {
516 {
517 .compatible = "ti,am3352-rtc",
518 .data = &omap_rtc_am3352_type,
519 }, {
520 .compatible = "ti,da830-rtc",
521 .data = &omap_rtc_da830_type,
522 }, {
523 /* sentinel */
524 }
525 };
526 MODULE_DEVICE_TABLE(of, omap_rtc_of_match);
527
528 static int omap_rtc_probe(struct platform_device *pdev)
529 {
530 struct omap_rtc *rtc;
531 struct resource *res;
532 u8 reg, mask, new_ctrl;
533 const struct platform_device_id *id_entry;
534 const struct of_device_id *of_id;
535 int ret;
536
537 rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
538 if (!rtc)
539 return -ENOMEM;
540
541 of_id = of_match_device(omap_rtc_of_match, &pdev->dev);
542 if (of_id) {
543 rtc->type = of_id->data;
544 rtc->is_pmic_controller = rtc->type->has_pmic_mode &&
545 of_property_read_bool(pdev->dev.of_node,
546 "system-power-controller");
547 } else {
548 id_entry = platform_get_device_id(pdev);
549 rtc->type = (void *)id_entry->driver_data;
550 }
551
552 rtc->irq_timer = platform_get_irq(pdev, 0);
553 if (rtc->irq_timer <= 0)
554 return -ENOENT;
555
556 rtc->irq_alarm = platform_get_irq(pdev, 1);
557 if (rtc->irq_alarm <= 0)
558 return -ENOENT;
559
560 rtc->clk = devm_clk_get(&pdev->dev, "ext-clk");
561 if (!IS_ERR(rtc->clk))
562 rtc->has_ext_clk = true;
563 else
564 rtc->clk = devm_clk_get(&pdev->dev, "int-clk");
565
566 if (!IS_ERR(rtc->clk))
567 clk_prepare_enable(rtc->clk);
568
569 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
570 rtc->base = devm_ioremap_resource(&pdev->dev, res);
571 if (IS_ERR(rtc->base))
572 return PTR_ERR(rtc->base);
573
574 platform_set_drvdata(pdev, rtc);
575
576 /* Enable the clock/module so that we can access the registers */
577 pm_runtime_enable(&pdev->dev);
578 pm_runtime_get_sync(&pdev->dev);
579
580 rtc->type->unlock(rtc);
581
582 /*
583 * disable interrupts
584 *
585 * NOTE: ALARM2 is not cleared on AM3352 if rtc_write (writeb) is used
586 */
587 rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
588
589 /* enable RTC functional clock */
590 if (rtc->type->has_32kclk_en) {
591 reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
592 rtc_writel(rtc, OMAP_RTC_OSC_REG,
593 reg | OMAP_RTC_OSC_32KCLK_EN);
594 }
595
596 /* clear old status */
597 reg = rtc_read(rtc, OMAP_RTC_STATUS_REG);
598
599 mask = OMAP_RTC_STATUS_ALARM;
600
601 if (rtc->type->has_pmic_mode)
602 mask |= OMAP_RTC_STATUS_ALARM2;
603
604 if (rtc->type->has_power_up_reset) {
605 mask |= OMAP_RTC_STATUS_POWER_UP;
606 if (reg & OMAP_RTC_STATUS_POWER_UP)
607 dev_info(&pdev->dev, "RTC power up reset detected\n");
608 }
609
610 if (reg & mask)
611 rtc_write(rtc, OMAP_RTC_STATUS_REG, reg & mask);
612
613 /* On boards with split power, RTC_ON_NOFF won't reset the RTC */
614 reg = rtc_read(rtc, OMAP_RTC_CTRL_REG);
615 if (reg & OMAP_RTC_CTRL_STOP)
616 dev_info(&pdev->dev, "already running\n");
617
618 /* force to 24 hour mode */
619 new_ctrl = reg & (OMAP_RTC_CTRL_SPLIT | OMAP_RTC_CTRL_AUTO_COMP);
620 new_ctrl |= OMAP_RTC_CTRL_STOP;
621
622 /*
623 * BOARD-SPECIFIC CUSTOMIZATION CAN GO HERE:
624 *
625 * - Device wake-up capability setting should come through chip
626 * init logic. OMAP1 boards should initialize the "wakeup capable"
627 * flag in the platform device if the board is wired right for
628 * being woken up by RTC alarm. For OMAP-L138, this capability
629 * is built into the SoC by the "Deep Sleep" capability.
630 *
631 * - Boards wired so RTC_ON_nOFF is used as the reset signal,
632 * rather than nPWRON_RESET, should forcibly enable split
633 * power mode. (Some chip errata report that RTC_CTRL_SPLIT
634 * is write-only, and always reads as zero...)
635 */
636
637 if (new_ctrl & OMAP_RTC_CTRL_SPLIT)
638 dev_info(&pdev->dev, "split power mode\n");
639
640 if (reg != new_ctrl)
641 rtc_write(rtc, OMAP_RTC_CTRL_REG, new_ctrl);
642
643 /*
644 * If we have the external clock then switch to it so we can keep
645 * ticking across suspend.
646 */
647 if (rtc->has_ext_clk) {
648 reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
649 rtc_write(rtc, OMAP_RTC_OSC_REG,
650 reg | OMAP_RTC_OSC_SEL_32KCLK_SRC);
651 }
652
653 rtc->type->lock(rtc);
654
655 device_init_wakeup(&pdev->dev, true);
656
657 rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
658 &omap_rtc_ops, THIS_MODULE);
659 if (IS_ERR(rtc->rtc)) {
660 ret = PTR_ERR(rtc->rtc);
661 goto err;
662 }
663
664 /* handle periodic and alarm irqs */
665 ret = devm_request_irq(&pdev->dev, rtc->irq_timer, rtc_irq, 0,
666 dev_name(&rtc->rtc->dev), rtc);
667 if (ret)
668 goto err;
669
670 if (rtc->irq_timer != rtc->irq_alarm) {
671 ret = devm_request_irq(&pdev->dev, rtc->irq_alarm, rtc_irq, 0,
672 dev_name(&rtc->rtc->dev), rtc);
673 if (ret)
674 goto err;
675 }
676
677 if (rtc->is_pmic_controller) {
678 if (!pm_power_off) {
679 omap_rtc_power_off_rtc = rtc;
680 pm_power_off = omap_rtc_power_off;
681 }
682 }
683
684 return 0;
685
686 err:
687 device_init_wakeup(&pdev->dev, false);
688 rtc->type->lock(rtc);
689 pm_runtime_put_sync(&pdev->dev);
690 pm_runtime_disable(&pdev->dev);
691
692 return ret;
693 }
694
695 static int __exit omap_rtc_remove(struct platform_device *pdev)
696 {
697 struct omap_rtc *rtc = platform_get_drvdata(pdev);
698 u8 reg;
699
700 if (pm_power_off == omap_rtc_power_off &&
701 omap_rtc_power_off_rtc == rtc) {
702 pm_power_off = NULL;
703 omap_rtc_power_off_rtc = NULL;
704 }
705
706 device_init_wakeup(&pdev->dev, 0);
707
708 if (!IS_ERR(rtc->clk))
709 clk_disable_unprepare(rtc->clk);
710
711 rtc->type->unlock(rtc);
712 /* leave rtc running, but disable irqs */
713 rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
714
715 if (rtc->has_ext_clk) {
716 reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
717 reg &= ~OMAP_RTC_OSC_SEL_32KCLK_SRC;
718 rtc_write(rtc, OMAP_RTC_OSC_REG, reg);
719 }
720
721 rtc->type->lock(rtc);
722
723 /* Disable the clock/module */
724 pm_runtime_put_sync(&pdev->dev);
725 pm_runtime_disable(&pdev->dev);
726
727 return 0;
728 }
729
730 #ifdef CONFIG_PM_SLEEP
731 static int omap_rtc_suspend(struct device *dev)
732 {
733 struct omap_rtc *rtc = dev_get_drvdata(dev);
734
735 rtc->interrupts_reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
736
737 rtc->type->unlock(rtc);
738 /*
739 * FIXME: the RTC alarm is not currently acting as a wakeup event
740 * source on some platforms, and in fact this enable() call is just
741 * saving a flag that's never used...
742 */
743 if (device_may_wakeup(dev))
744 enable_irq_wake(rtc->irq_alarm);
745 else
746 rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
747 rtc->type->lock(rtc);
748
749 /* Disable the clock/module */
750 pm_runtime_put_sync(dev);
751
752 return 0;
753 }
754
755 static int omap_rtc_resume(struct device *dev)
756 {
757 struct omap_rtc *rtc = dev_get_drvdata(dev);
758
759 /* Enable the clock/module so that we can access the registers */
760 pm_runtime_get_sync(dev);
761
762 rtc->type->unlock(rtc);
763 if (device_may_wakeup(dev))
764 disable_irq_wake(rtc->irq_alarm);
765 else
766 rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, rtc->interrupts_reg);
767 rtc->type->lock(rtc);
768
769 return 0;
770 }
771 #endif
772
773 static SIMPLE_DEV_PM_OPS(omap_rtc_pm_ops, omap_rtc_suspend, omap_rtc_resume);
774
775 static void omap_rtc_shutdown(struct platform_device *pdev)
776 {
777 struct omap_rtc *rtc = platform_get_drvdata(pdev);
778 u8 mask;
779
780 /*
781 * Keep the ALARM interrupt enabled to allow the system to power up on
782 * alarm events.
783 */
784 rtc->type->unlock(rtc);
785 mask = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
786 mask &= OMAP_RTC_INTERRUPTS_IT_ALARM;
787 rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, mask);
788 rtc->type->lock(rtc);
789 }
790
791 static struct platform_driver omap_rtc_driver = {
792 .probe = omap_rtc_probe,
793 .remove = __exit_p(omap_rtc_remove),
794 .shutdown = omap_rtc_shutdown,
795 .driver = {
796 .name = "omap_rtc",
797 .pm = &omap_rtc_pm_ops,
798 .of_match_table = omap_rtc_of_match,
799 },
800 .id_table = omap_rtc_id_table,
801 };
802
803 module_platform_driver(omap_rtc_driver);
804
805 MODULE_ALIAS("platform:omap_rtc");
806 MODULE_AUTHOR("George G. Davis (and others)");
807 MODULE_LICENSE("GPL");
Linux kernel - Deliverables
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