xref: /linux/drivers/rtc/rtc-twl.c (revision b85d45947951d23cb22d90caecf4c1eb81342c96)
1 /*
2  * rtc-twl.c -- TWL Real Time Clock interface
3  *
4  * Copyright (C) 2007 MontaVista Software, Inc
5  * Author: Alexandre Rusev <source@mvista.com>
6  *
7  * Based on original TI driver twl4030-rtc.c
8  *   Copyright (C) 2006 Texas Instruments, Inc.
9  *
10  * Based on rtc-omap.c
11  *   Copyright (C) 2003 MontaVista Software, Inc.
12  *   Author: George G. Davis <gdavis@mvista.com> or <source@mvista.com>
13  *   Copyright (C) 2006 David Brownell
14  *
15  * This program is free software; you can redistribute it and/or
16  * modify it under the terms of the GNU General Public License
17  * as published by the Free Software Foundation; either version
18  * 2 of the License, or (at your option) any later version.
19  */
20 
21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22 
23 #include <linux/kernel.h>
24 #include <linux/errno.h>
25 #include <linux/init.h>
26 #include <linux/module.h>
27 #include <linux/types.h>
28 #include <linux/rtc.h>
29 #include <linux/bcd.h>
30 #include <linux/platform_device.h>
31 #include <linux/interrupt.h>
32 #include <linux/of.h>
33 
34 #include <linux/i2c/twl.h>
35 
36 
37 /*
38  * RTC block register offsets (use TWL_MODULE_RTC)
39  */
40 enum {
41 	REG_SECONDS_REG = 0,
42 	REG_MINUTES_REG,
43 	REG_HOURS_REG,
44 	REG_DAYS_REG,
45 	REG_MONTHS_REG,
46 	REG_YEARS_REG,
47 	REG_WEEKS_REG,
48 
49 	REG_ALARM_SECONDS_REG,
50 	REG_ALARM_MINUTES_REG,
51 	REG_ALARM_HOURS_REG,
52 	REG_ALARM_DAYS_REG,
53 	REG_ALARM_MONTHS_REG,
54 	REG_ALARM_YEARS_REG,
55 
56 	REG_RTC_CTRL_REG,
57 	REG_RTC_STATUS_REG,
58 	REG_RTC_INTERRUPTS_REG,
59 
60 	REG_RTC_COMP_LSB_REG,
61 	REG_RTC_COMP_MSB_REG,
62 };
63 static const u8 twl4030_rtc_reg_map[] = {
64 	[REG_SECONDS_REG] = 0x00,
65 	[REG_MINUTES_REG] = 0x01,
66 	[REG_HOURS_REG] = 0x02,
67 	[REG_DAYS_REG] = 0x03,
68 	[REG_MONTHS_REG] = 0x04,
69 	[REG_YEARS_REG] = 0x05,
70 	[REG_WEEKS_REG] = 0x06,
71 
72 	[REG_ALARM_SECONDS_REG] = 0x07,
73 	[REG_ALARM_MINUTES_REG] = 0x08,
74 	[REG_ALARM_HOURS_REG] = 0x09,
75 	[REG_ALARM_DAYS_REG] = 0x0A,
76 	[REG_ALARM_MONTHS_REG] = 0x0B,
77 	[REG_ALARM_YEARS_REG] = 0x0C,
78 
79 	[REG_RTC_CTRL_REG] = 0x0D,
80 	[REG_RTC_STATUS_REG] = 0x0E,
81 	[REG_RTC_INTERRUPTS_REG] = 0x0F,
82 
83 	[REG_RTC_COMP_LSB_REG] = 0x10,
84 	[REG_RTC_COMP_MSB_REG] = 0x11,
85 };
86 static const u8 twl6030_rtc_reg_map[] = {
87 	[REG_SECONDS_REG] = 0x00,
88 	[REG_MINUTES_REG] = 0x01,
89 	[REG_HOURS_REG] = 0x02,
90 	[REG_DAYS_REG] = 0x03,
91 	[REG_MONTHS_REG] = 0x04,
92 	[REG_YEARS_REG] = 0x05,
93 	[REG_WEEKS_REG] = 0x06,
94 
95 	[REG_ALARM_SECONDS_REG] = 0x08,
96 	[REG_ALARM_MINUTES_REG] = 0x09,
97 	[REG_ALARM_HOURS_REG] = 0x0A,
98 	[REG_ALARM_DAYS_REG] = 0x0B,
99 	[REG_ALARM_MONTHS_REG] = 0x0C,
100 	[REG_ALARM_YEARS_REG] = 0x0D,
101 
102 	[REG_RTC_CTRL_REG] = 0x10,
103 	[REG_RTC_STATUS_REG] = 0x11,
104 	[REG_RTC_INTERRUPTS_REG] = 0x12,
105 
106 	[REG_RTC_COMP_LSB_REG] = 0x13,
107 	[REG_RTC_COMP_MSB_REG] = 0x14,
108 };
109 
110 /* RTC_CTRL_REG bitfields */
111 #define BIT_RTC_CTRL_REG_STOP_RTC_M              0x01
112 #define BIT_RTC_CTRL_REG_ROUND_30S_M             0x02
113 #define BIT_RTC_CTRL_REG_AUTO_COMP_M             0x04
114 #define BIT_RTC_CTRL_REG_MODE_12_24_M            0x08
115 #define BIT_RTC_CTRL_REG_TEST_MODE_M             0x10
116 #define BIT_RTC_CTRL_REG_SET_32_COUNTER_M        0x20
117 #define BIT_RTC_CTRL_REG_GET_TIME_M              0x40
118 #define BIT_RTC_CTRL_REG_RTC_V_OPT               0x80
119 
120 /* RTC_STATUS_REG bitfields */
121 #define BIT_RTC_STATUS_REG_RUN_M                 0x02
122 #define BIT_RTC_STATUS_REG_1S_EVENT_M            0x04
123 #define BIT_RTC_STATUS_REG_1M_EVENT_M            0x08
124 #define BIT_RTC_STATUS_REG_1H_EVENT_M            0x10
125 #define BIT_RTC_STATUS_REG_1D_EVENT_M            0x20
126 #define BIT_RTC_STATUS_REG_ALARM_M               0x40
127 #define BIT_RTC_STATUS_REG_POWER_UP_M            0x80
128 
129 /* RTC_INTERRUPTS_REG bitfields */
130 #define BIT_RTC_INTERRUPTS_REG_EVERY_M           0x03
131 #define BIT_RTC_INTERRUPTS_REG_IT_TIMER_M        0x04
132 #define BIT_RTC_INTERRUPTS_REG_IT_ALARM_M        0x08
133 
134 
135 /* REG_SECONDS_REG through REG_YEARS_REG is how many registers? */
136 #define ALL_TIME_REGS		6
137 
138 /*----------------------------------------------------------------------*/
139 static u8  *rtc_reg_map;
140 
141 /*
142  * Supports 1 byte read from TWL RTC register.
143  */
144 static int twl_rtc_read_u8(u8 *data, u8 reg)
145 {
146 	int ret;
147 
148 	ret = twl_i2c_read_u8(TWL_MODULE_RTC, data, (rtc_reg_map[reg]));
149 	if (ret < 0)
150 		pr_err("Could not read TWL register %X - error %d\n", reg, ret);
151 	return ret;
152 }
153 
154 /*
155  * Supports 1 byte write to TWL RTC registers.
156  */
157 static int twl_rtc_write_u8(u8 data, u8 reg)
158 {
159 	int ret;
160 
161 	ret = twl_i2c_write_u8(TWL_MODULE_RTC, data, (rtc_reg_map[reg]));
162 	if (ret < 0)
163 		pr_err("Could not write TWL register %X - error %d\n",
164 		       reg, ret);
165 	return ret;
166 }
167 
168 /*
169  * Cache the value for timer/alarm interrupts register; this is
170  * only changed by callers holding rtc ops lock (or resume).
171  */
172 static unsigned char rtc_irq_bits;
173 
174 /*
175  * Enable 1/second update and/or alarm interrupts.
176  */
177 static int set_rtc_irq_bit(unsigned char bit)
178 {
179 	unsigned char val;
180 	int ret;
181 
182 	/* if the bit is set, return from here */
183 	if (rtc_irq_bits & bit)
184 		return 0;
185 
186 	val = rtc_irq_bits | bit;
187 	val &= ~BIT_RTC_INTERRUPTS_REG_EVERY_M;
188 	ret = twl_rtc_write_u8(val, REG_RTC_INTERRUPTS_REG);
189 	if (ret == 0)
190 		rtc_irq_bits = val;
191 
192 	return ret;
193 }
194 
195 /*
196  * Disable update and/or alarm interrupts.
197  */
198 static int mask_rtc_irq_bit(unsigned char bit)
199 {
200 	unsigned char val;
201 	int ret;
202 
203 	/* if the bit is clear, return from here */
204 	if (!(rtc_irq_bits & bit))
205 		return 0;
206 
207 	val = rtc_irq_bits & ~bit;
208 	ret = twl_rtc_write_u8(val, REG_RTC_INTERRUPTS_REG);
209 	if (ret == 0)
210 		rtc_irq_bits = val;
211 
212 	return ret;
213 }
214 
215 static int twl_rtc_alarm_irq_enable(struct device *dev, unsigned enabled)
216 {
217 	struct platform_device *pdev = to_platform_device(dev);
218 	int irq = platform_get_irq(pdev, 0);
219 	static bool twl_rtc_wake_enabled;
220 	int ret;
221 
222 	if (enabled) {
223 		ret = set_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_ALARM_M);
224 		if (device_can_wakeup(dev) && !twl_rtc_wake_enabled) {
225 			enable_irq_wake(irq);
226 			twl_rtc_wake_enabled = true;
227 		}
228 	} else {
229 		ret = mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_ALARM_M);
230 		if (twl_rtc_wake_enabled) {
231 			disable_irq_wake(irq);
232 			twl_rtc_wake_enabled = false;
233 		}
234 	}
235 
236 	return ret;
237 }
238 
239 /*
240  * Gets current TWL RTC time and date parameters.
241  *
242  * The RTC's time/alarm representation is not what gmtime(3) requires
243  * Linux to use:
244  *
245  *  - Months are 1..12 vs Linux 0-11
246  *  - Years are 0..99 vs Linux 1900..N (we assume 21st century)
247  */
248 static int twl_rtc_read_time(struct device *dev, struct rtc_time *tm)
249 {
250 	unsigned char rtc_data[ALL_TIME_REGS];
251 	int ret;
252 	u8 save_control;
253 	u8 rtc_control;
254 
255 	ret = twl_rtc_read_u8(&save_control, REG_RTC_CTRL_REG);
256 	if (ret < 0) {
257 		dev_err(dev, "%s: reading CTRL_REG, error %d\n", __func__, ret);
258 		return ret;
259 	}
260 	/* for twl6030/32 make sure BIT_RTC_CTRL_REG_GET_TIME_M is clear */
261 	if (twl_class_is_6030()) {
262 		if (save_control & BIT_RTC_CTRL_REG_GET_TIME_M) {
263 			save_control &= ~BIT_RTC_CTRL_REG_GET_TIME_M;
264 			ret = twl_rtc_write_u8(save_control, REG_RTC_CTRL_REG);
265 			if (ret < 0) {
266 				dev_err(dev, "%s clr GET_TIME, error %d\n",
267 					__func__, ret);
268 				return ret;
269 			}
270 		}
271 	}
272 
273 	/* Copy RTC counting registers to static registers or latches */
274 	rtc_control = save_control | BIT_RTC_CTRL_REG_GET_TIME_M;
275 
276 	/* for twl6030/32 enable read access to static shadowed registers */
277 	if (twl_class_is_6030())
278 		rtc_control |= BIT_RTC_CTRL_REG_RTC_V_OPT;
279 
280 	ret = twl_rtc_write_u8(rtc_control, REG_RTC_CTRL_REG);
281 	if (ret < 0) {
282 		dev_err(dev, "%s: writing CTRL_REG, error %d\n", __func__, ret);
283 		return ret;
284 	}
285 
286 	ret = twl_i2c_read(TWL_MODULE_RTC, rtc_data,
287 			(rtc_reg_map[REG_SECONDS_REG]), ALL_TIME_REGS);
288 
289 	if (ret < 0) {
290 		dev_err(dev, "%s: reading data, error %d\n", __func__, ret);
291 		return ret;
292 	}
293 
294 	/* for twl6030 restore original state of rtc control register */
295 	if (twl_class_is_6030()) {
296 		ret = twl_rtc_write_u8(save_control, REG_RTC_CTRL_REG);
297 		if (ret < 0) {
298 			dev_err(dev, "%s: restore CTRL_REG, error %d\n",
299 				__func__, ret);
300 			return ret;
301 		}
302 	}
303 
304 	tm->tm_sec = bcd2bin(rtc_data[0]);
305 	tm->tm_min = bcd2bin(rtc_data[1]);
306 	tm->tm_hour = bcd2bin(rtc_data[2]);
307 	tm->tm_mday = bcd2bin(rtc_data[3]);
308 	tm->tm_mon = bcd2bin(rtc_data[4]) - 1;
309 	tm->tm_year = bcd2bin(rtc_data[5]) + 100;
310 
311 	return ret;
312 }
313 
314 static int twl_rtc_set_time(struct device *dev, struct rtc_time *tm)
315 {
316 	unsigned char save_control;
317 	unsigned char rtc_data[ALL_TIME_REGS];
318 	int ret;
319 
320 	rtc_data[0] = bin2bcd(tm->tm_sec);
321 	rtc_data[1] = bin2bcd(tm->tm_min);
322 	rtc_data[2] = bin2bcd(tm->tm_hour);
323 	rtc_data[3] = bin2bcd(tm->tm_mday);
324 	rtc_data[4] = bin2bcd(tm->tm_mon + 1);
325 	rtc_data[5] = bin2bcd(tm->tm_year - 100);
326 
327 	/* Stop RTC while updating the TC registers */
328 	ret = twl_rtc_read_u8(&save_control, REG_RTC_CTRL_REG);
329 	if (ret < 0)
330 		goto out;
331 
332 	save_control &= ~BIT_RTC_CTRL_REG_STOP_RTC_M;
333 	ret = twl_rtc_write_u8(save_control, REG_RTC_CTRL_REG);
334 	if (ret < 0)
335 		goto out;
336 
337 	/* update all the time registers in one shot */
338 	ret = twl_i2c_write(TWL_MODULE_RTC, rtc_data,
339 		(rtc_reg_map[REG_SECONDS_REG]), ALL_TIME_REGS);
340 	if (ret < 0) {
341 		dev_err(dev, "rtc_set_time error %d\n", ret);
342 		goto out;
343 	}
344 
345 	/* Start back RTC */
346 	save_control |= BIT_RTC_CTRL_REG_STOP_RTC_M;
347 	ret = twl_rtc_write_u8(save_control, REG_RTC_CTRL_REG);
348 
349 out:
350 	return ret;
351 }
352 
353 /*
354  * Gets current TWL RTC alarm time.
355  */
356 static int twl_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
357 {
358 	unsigned char rtc_data[ALL_TIME_REGS];
359 	int ret;
360 
361 	ret = twl_i2c_read(TWL_MODULE_RTC, rtc_data,
362 			(rtc_reg_map[REG_ALARM_SECONDS_REG]), ALL_TIME_REGS);
363 	if (ret < 0) {
364 		dev_err(dev, "rtc_read_alarm error %d\n", ret);
365 		return ret;
366 	}
367 
368 	/* some of these fields may be wildcard/"match all" */
369 	alm->time.tm_sec = bcd2bin(rtc_data[0]);
370 	alm->time.tm_min = bcd2bin(rtc_data[1]);
371 	alm->time.tm_hour = bcd2bin(rtc_data[2]);
372 	alm->time.tm_mday = bcd2bin(rtc_data[3]);
373 	alm->time.tm_mon = bcd2bin(rtc_data[4]) - 1;
374 	alm->time.tm_year = bcd2bin(rtc_data[5]) + 100;
375 
376 	/* report cached alarm enable state */
377 	if (rtc_irq_bits & BIT_RTC_INTERRUPTS_REG_IT_ALARM_M)
378 		alm->enabled = 1;
379 
380 	return ret;
381 }
382 
383 static int twl_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
384 {
385 	unsigned char alarm_data[ALL_TIME_REGS];
386 	int ret;
387 
388 	ret = twl_rtc_alarm_irq_enable(dev, 0);
389 	if (ret)
390 		goto out;
391 
392 	alarm_data[0] = bin2bcd(alm->time.tm_sec);
393 	alarm_data[1] = bin2bcd(alm->time.tm_min);
394 	alarm_data[2] = bin2bcd(alm->time.tm_hour);
395 	alarm_data[3] = bin2bcd(alm->time.tm_mday);
396 	alarm_data[4] = bin2bcd(alm->time.tm_mon + 1);
397 	alarm_data[5] = bin2bcd(alm->time.tm_year - 100);
398 
399 	/* update all the alarm registers in one shot */
400 	ret = twl_i2c_write(TWL_MODULE_RTC, alarm_data,
401 		(rtc_reg_map[REG_ALARM_SECONDS_REG]), ALL_TIME_REGS);
402 	if (ret) {
403 		dev_err(dev, "rtc_set_alarm error %d\n", ret);
404 		goto out;
405 	}
406 
407 	if (alm->enabled)
408 		ret = twl_rtc_alarm_irq_enable(dev, 1);
409 out:
410 	return ret;
411 }
412 
413 static irqreturn_t twl_rtc_interrupt(int irq, void *rtc)
414 {
415 	unsigned long events;
416 	int ret = IRQ_NONE;
417 	int res;
418 	u8 rd_reg;
419 
420 	res = twl_rtc_read_u8(&rd_reg, REG_RTC_STATUS_REG);
421 	if (res)
422 		goto out;
423 	/*
424 	 * Figure out source of interrupt: ALARM or TIMER in RTC_STATUS_REG.
425 	 * only one (ALARM or RTC) interrupt source may be enabled
426 	 * at time, we also could check our results
427 	 * by reading RTS_INTERRUPTS_REGISTER[IT_TIMER,IT_ALARM]
428 	 */
429 	if (rd_reg & BIT_RTC_STATUS_REG_ALARM_M)
430 		events = RTC_IRQF | RTC_AF;
431 	else
432 		events = RTC_IRQF | RTC_PF;
433 
434 	res = twl_rtc_write_u8(BIT_RTC_STATUS_REG_ALARM_M,
435 				   REG_RTC_STATUS_REG);
436 	if (res)
437 		goto out;
438 
439 	if (twl_class_is_4030()) {
440 		/* Clear on Read enabled. RTC_IT bit of TWL4030_INT_PWR_ISR1
441 		 * needs 2 reads to clear the interrupt. One read is done in
442 		 * do_twl_pwrirq(). Doing the second read, to clear
443 		 * the bit.
444 		 *
445 		 * FIXME the reason PWR_ISR1 needs an extra read is that
446 		 * RTC_IF retriggered until we cleared REG_ALARM_M above.
447 		 * But re-reading like this is a bad hack; by doing so we
448 		 * risk wrongly clearing status for some other IRQ (losing
449 		 * the interrupt).  Be smarter about handling RTC_UF ...
450 		 */
451 		res = twl_i2c_read_u8(TWL4030_MODULE_INT,
452 			&rd_reg, TWL4030_INT_PWR_ISR1);
453 		if (res)
454 			goto out;
455 	}
456 
457 	/* Notify RTC core on event */
458 	rtc_update_irq(rtc, 1, events);
459 
460 	ret = IRQ_HANDLED;
461 out:
462 	return ret;
463 }
464 
465 static struct rtc_class_ops twl_rtc_ops = {
466 	.read_time	= twl_rtc_read_time,
467 	.set_time	= twl_rtc_set_time,
468 	.read_alarm	= twl_rtc_read_alarm,
469 	.set_alarm	= twl_rtc_set_alarm,
470 	.alarm_irq_enable = twl_rtc_alarm_irq_enable,
471 };
472 
473 /*----------------------------------------------------------------------*/
474 
475 static int twl_rtc_probe(struct platform_device *pdev)
476 {
477 	struct rtc_device *rtc;
478 	int ret = -EINVAL;
479 	int irq = platform_get_irq(pdev, 0);
480 	u8 rd_reg;
481 
482 	if (irq <= 0)
483 		return ret;
484 
485 	/* Initialize the register map */
486 	if (twl_class_is_4030())
487 		rtc_reg_map = (u8 *)twl4030_rtc_reg_map;
488 	else
489 		rtc_reg_map = (u8 *)twl6030_rtc_reg_map;
490 
491 	ret = twl_rtc_read_u8(&rd_reg, REG_RTC_STATUS_REG);
492 	if (ret < 0)
493 		return ret;
494 
495 	if (rd_reg & BIT_RTC_STATUS_REG_POWER_UP_M)
496 		dev_warn(&pdev->dev, "Power up reset detected.\n");
497 
498 	if (rd_reg & BIT_RTC_STATUS_REG_ALARM_M)
499 		dev_warn(&pdev->dev, "Pending Alarm interrupt detected.\n");
500 
501 	/* Clear RTC Power up reset and pending alarm interrupts */
502 	ret = twl_rtc_write_u8(rd_reg, REG_RTC_STATUS_REG);
503 	if (ret < 0)
504 		return ret;
505 
506 	if (twl_class_is_6030()) {
507 		twl6030_interrupt_unmask(TWL6030_RTC_INT_MASK,
508 			REG_INT_MSK_LINE_A);
509 		twl6030_interrupt_unmask(TWL6030_RTC_INT_MASK,
510 			REG_INT_MSK_STS_A);
511 	}
512 
513 	dev_info(&pdev->dev, "Enabling TWL-RTC\n");
514 	ret = twl_rtc_write_u8(BIT_RTC_CTRL_REG_STOP_RTC_M, REG_RTC_CTRL_REG);
515 	if (ret < 0)
516 		return ret;
517 
518 	/* ensure interrupts are disabled, bootloaders can be strange */
519 	ret = twl_rtc_write_u8(0, REG_RTC_INTERRUPTS_REG);
520 	if (ret < 0)
521 		dev_warn(&pdev->dev, "unable to disable interrupt\n");
522 
523 	/* init cached IRQ enable bits */
524 	ret = twl_rtc_read_u8(&rtc_irq_bits, REG_RTC_INTERRUPTS_REG);
525 	if (ret < 0)
526 		return ret;
527 
528 	device_init_wakeup(&pdev->dev, 1);
529 
530 	rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
531 					&twl_rtc_ops, THIS_MODULE);
532 	if (IS_ERR(rtc)) {
533 		dev_err(&pdev->dev, "can't register RTC device, err %ld\n",
534 			PTR_ERR(rtc));
535 		return PTR_ERR(rtc);
536 	}
537 
538 	ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
539 					twl_rtc_interrupt,
540 					IRQF_TRIGGER_RISING | IRQF_ONESHOT,
541 					dev_name(&rtc->dev), rtc);
542 	if (ret < 0) {
543 		dev_err(&pdev->dev, "IRQ is not free.\n");
544 		return ret;
545 	}
546 
547 	platform_set_drvdata(pdev, rtc);
548 	return 0;
549 }
550 
551 /*
552  * Disable all TWL RTC module interrupts.
553  * Sets status flag to free.
554  */
555 static int twl_rtc_remove(struct platform_device *pdev)
556 {
557 	/* leave rtc running, but disable irqs */
558 	mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_ALARM_M);
559 	mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_TIMER_M);
560 	if (twl_class_is_6030()) {
561 		twl6030_interrupt_mask(TWL6030_RTC_INT_MASK,
562 			REG_INT_MSK_LINE_A);
563 		twl6030_interrupt_mask(TWL6030_RTC_INT_MASK,
564 			REG_INT_MSK_STS_A);
565 	}
566 
567 	return 0;
568 }
569 
570 static void twl_rtc_shutdown(struct platform_device *pdev)
571 {
572 	/* mask timer interrupts, but leave alarm interrupts on to enable
573 	   power-on when alarm is triggered */
574 	mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_TIMER_M);
575 }
576 
577 #ifdef CONFIG_PM_SLEEP
578 static unsigned char irqstat;
579 
580 static int twl_rtc_suspend(struct device *dev)
581 {
582 	irqstat = rtc_irq_bits;
583 
584 	mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_TIMER_M);
585 	return 0;
586 }
587 
588 static int twl_rtc_resume(struct device *dev)
589 {
590 	set_rtc_irq_bit(irqstat);
591 	return 0;
592 }
593 #endif
594 
595 static SIMPLE_DEV_PM_OPS(twl_rtc_pm_ops, twl_rtc_suspend, twl_rtc_resume);
596 
597 #ifdef CONFIG_OF
598 static const struct of_device_id twl_rtc_of_match[] = {
599 	{.compatible = "ti,twl4030-rtc", },
600 	{ },
601 };
602 MODULE_DEVICE_TABLE(of, twl_rtc_of_match);
603 #endif
604 
605 MODULE_ALIAS("platform:twl_rtc");
606 
607 static struct platform_driver twl4030rtc_driver = {
608 	.probe		= twl_rtc_probe,
609 	.remove		= twl_rtc_remove,
610 	.shutdown	= twl_rtc_shutdown,
611 	.driver		= {
612 		.name		= "twl_rtc",
613 		.pm		= &twl_rtc_pm_ops,
614 		.of_match_table = of_match_ptr(twl_rtc_of_match),
615 	},
616 };
617 
618 module_platform_driver(twl4030rtc_driver);
619 
620 MODULE_AUTHOR("Texas Instruments, MontaVista Software");
621 MODULE_LICENSE("GPL");
622