1 /*
2  * DaVinci Power Management and Real Time Clock Driver for TI platforms
3  *
4  * Copyright (C) 2009 Texas Instruments, Inc
5  *
6  * Author: Miguel Aguilar <miguel.aguilar@ridgerun.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21  */
22 #include <linux/kernel.h>
23 #include <linux/init.h>
24 #include <linux/module.h>
25 #include <linux/ioport.h>
26 #include <linux/delay.h>
27 #include <linux/spinlock.h>
28 #include <linux/rtc.h>
29 #include <linux/bcd.h>
30 #include <linux/platform_device.h>
31 #include <linux/io.h>
32 #include <linux/slab.h>
33 
34 /*
35  * The DaVinci RTC is a simple RTC with the following
36  * Sec: 0 - 59 : BCD count
37  * Min: 0 - 59 : BCD count
38  * Hour: 0 - 23 : BCD count
39  * Day: 0 - 0x7FFF(32767) : Binary count ( Over 89 years )
40  */
41 
42 /* PRTC interface registers */
43 #define DAVINCI_PRTCIF_PID		0x00
44 #define PRTCIF_CTLR			0x04
45 #define PRTCIF_LDATA			0x08
46 #define PRTCIF_UDATA			0x0C
47 #define PRTCIF_INTEN			0x10
48 #define PRTCIF_INTFLG			0x14
49 
50 /* PRTCIF_CTLR bit fields */
51 #define PRTCIF_CTLR_BUSY		BIT(31)
52 #define PRTCIF_CTLR_SIZE		BIT(25)
53 #define PRTCIF_CTLR_DIR			BIT(24)
54 #define PRTCIF_CTLR_BENU_MSB		BIT(23)
55 #define PRTCIF_CTLR_BENU_3RD_BYTE	BIT(22)
56 #define PRTCIF_CTLR_BENU_2ND_BYTE	BIT(21)
57 #define PRTCIF_CTLR_BENU_LSB		BIT(20)
58 #define PRTCIF_CTLR_BENU_MASK		(0x00F00000)
59 #define PRTCIF_CTLR_BENL_MSB		BIT(19)
60 #define PRTCIF_CTLR_BENL_3RD_BYTE	BIT(18)
61 #define PRTCIF_CTLR_BENL_2ND_BYTE	BIT(17)
62 #define PRTCIF_CTLR_BENL_LSB		BIT(16)
63 #define PRTCIF_CTLR_BENL_MASK		(0x000F0000)
64 
65 /* PRTCIF_INTEN bit fields */
66 #define PRTCIF_INTEN_RTCSS		BIT(1)
67 #define PRTCIF_INTEN_RTCIF		BIT(0)
68 #define PRTCIF_INTEN_MASK		(PRTCIF_INTEN_RTCSS \
69 					| PRTCIF_INTEN_RTCIF)
70 
71 /* PRTCIF_INTFLG bit fields */
72 #define PRTCIF_INTFLG_RTCSS		BIT(1)
73 #define PRTCIF_INTFLG_RTCIF		BIT(0)
74 #define PRTCIF_INTFLG_MASK		(PRTCIF_INTFLG_RTCSS \
75 					| PRTCIF_INTFLG_RTCIF)
76 
77 /* PRTC subsystem registers */
78 #define PRTCSS_RTC_INTC_EXTENA1		(0x0C)
79 #define PRTCSS_RTC_CTRL			(0x10)
80 #define PRTCSS_RTC_WDT			(0x11)
81 #define PRTCSS_RTC_TMR0			(0x12)
82 #define PRTCSS_RTC_TMR1			(0x13)
83 #define PRTCSS_RTC_CCTRL		(0x14)
84 #define PRTCSS_RTC_SEC			(0x15)
85 #define PRTCSS_RTC_MIN			(0x16)
86 #define PRTCSS_RTC_HOUR			(0x17)
87 #define PRTCSS_RTC_DAY0			(0x18)
88 #define PRTCSS_RTC_DAY1			(0x19)
89 #define PRTCSS_RTC_AMIN			(0x1A)
90 #define PRTCSS_RTC_AHOUR		(0x1B)
91 #define PRTCSS_RTC_ADAY0		(0x1C)
92 #define PRTCSS_RTC_ADAY1		(0x1D)
93 #define PRTCSS_RTC_CLKC_CNT		(0x20)
94 
95 /* PRTCSS_RTC_INTC_EXTENA1 */
96 #define PRTCSS_RTC_INTC_EXTENA1_MASK	(0x07)
97 
98 /* PRTCSS_RTC_CTRL bit fields */
99 #define PRTCSS_RTC_CTRL_WDTBUS		BIT(7)
100 #define PRTCSS_RTC_CTRL_WEN		BIT(6)
101 #define PRTCSS_RTC_CTRL_WDRT		BIT(5)
102 #define PRTCSS_RTC_CTRL_WDTFLG		BIT(4)
103 #define PRTCSS_RTC_CTRL_TE		BIT(3)
104 #define PRTCSS_RTC_CTRL_TIEN		BIT(2)
105 #define PRTCSS_RTC_CTRL_TMRFLG		BIT(1)
106 #define PRTCSS_RTC_CTRL_TMMD		BIT(0)
107 
108 /* PRTCSS_RTC_CCTRL bit fields */
109 #define PRTCSS_RTC_CCTRL_CALBUSY	BIT(7)
110 #define PRTCSS_RTC_CCTRL_DAEN		BIT(5)
111 #define PRTCSS_RTC_CCTRL_HAEN		BIT(4)
112 #define PRTCSS_RTC_CCTRL_MAEN		BIT(3)
113 #define PRTCSS_RTC_CCTRL_ALMFLG		BIT(2)
114 #define PRTCSS_RTC_CCTRL_AIEN		BIT(1)
115 #define PRTCSS_RTC_CCTRL_CAEN		BIT(0)
116 
117 static DEFINE_SPINLOCK(davinci_rtc_lock);
118 
119 struct davinci_rtc {
120 	struct rtc_device		*rtc;
121 	void __iomem			*base;
122 	int				irq;
123 };
124 
rtcif_write(struct davinci_rtc * davinci_rtc,u32 val,u32 addr)125 static inline void rtcif_write(struct davinci_rtc *davinci_rtc,
126 			       u32 val, u32 addr)
127 {
128 	writel(val, davinci_rtc->base + addr);
129 }
130 
rtcif_read(struct davinci_rtc * davinci_rtc,u32 addr)131 static inline u32 rtcif_read(struct davinci_rtc *davinci_rtc, u32 addr)
132 {
133 	return readl(davinci_rtc->base + addr);
134 }
135 
rtcif_wait(struct davinci_rtc * davinci_rtc)136 static inline void rtcif_wait(struct davinci_rtc *davinci_rtc)
137 {
138 	while (rtcif_read(davinci_rtc, PRTCIF_CTLR) & PRTCIF_CTLR_BUSY)
139 		cpu_relax();
140 }
141 
rtcss_write(struct davinci_rtc * davinci_rtc,unsigned long val,u8 addr)142 static inline void rtcss_write(struct davinci_rtc *davinci_rtc,
143 			       unsigned long val, u8 addr)
144 {
145 	rtcif_wait(davinci_rtc);
146 
147 	rtcif_write(davinci_rtc, PRTCIF_CTLR_BENL_LSB | addr, PRTCIF_CTLR);
148 	rtcif_write(davinci_rtc, val, PRTCIF_LDATA);
149 
150 	rtcif_wait(davinci_rtc);
151 }
152 
rtcss_read(struct davinci_rtc * davinci_rtc,u8 addr)153 static inline u8 rtcss_read(struct davinci_rtc *davinci_rtc, u8 addr)
154 {
155 	rtcif_wait(davinci_rtc);
156 
157 	rtcif_write(davinci_rtc, PRTCIF_CTLR_DIR | PRTCIF_CTLR_BENL_LSB | addr,
158 		    PRTCIF_CTLR);
159 
160 	rtcif_wait(davinci_rtc);
161 
162 	return rtcif_read(davinci_rtc, PRTCIF_LDATA);
163 }
164 
davinci_rtcss_calendar_wait(struct davinci_rtc * davinci_rtc)165 static inline void davinci_rtcss_calendar_wait(struct davinci_rtc *davinci_rtc)
166 {
167 	while (rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL) &
168 	       PRTCSS_RTC_CCTRL_CALBUSY)
169 		cpu_relax();
170 }
171 
davinci_rtc_interrupt(int irq,void * class_dev)172 static irqreturn_t davinci_rtc_interrupt(int irq, void *class_dev)
173 {
174 	struct davinci_rtc *davinci_rtc = class_dev;
175 	unsigned long events = 0;
176 	u32 irq_flg;
177 	u8 alm_irq, tmr_irq;
178 	u8 rtc_ctrl, rtc_cctrl;
179 	int ret = IRQ_NONE;
180 
181 	irq_flg = rtcif_read(davinci_rtc, PRTCIF_INTFLG) &
182 		  PRTCIF_INTFLG_RTCSS;
183 
184 	alm_irq = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL) &
185 		  PRTCSS_RTC_CCTRL_ALMFLG;
186 
187 	tmr_irq = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL) &
188 		  PRTCSS_RTC_CTRL_TMRFLG;
189 
190 	if (irq_flg) {
191 		if (alm_irq) {
192 			events |= RTC_IRQF | RTC_AF;
193 			rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
194 			rtc_cctrl |=  PRTCSS_RTC_CCTRL_ALMFLG;
195 			rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
196 		} else if (tmr_irq) {
197 			events |= RTC_IRQF | RTC_PF;
198 			rtc_ctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL);
199 			rtc_ctrl |=  PRTCSS_RTC_CTRL_TMRFLG;
200 			rtcss_write(davinci_rtc, rtc_ctrl, PRTCSS_RTC_CTRL);
201 		}
202 
203 		rtcif_write(davinci_rtc, PRTCIF_INTFLG_RTCSS,
204 				    PRTCIF_INTFLG);
205 		rtc_update_irq(davinci_rtc->rtc, 1, events);
206 
207 		ret = IRQ_HANDLED;
208 	}
209 
210 	return ret;
211 }
212 
213 static int
davinci_rtc_ioctl(struct device * dev,unsigned int cmd,unsigned long arg)214 davinci_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
215 {
216 	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
217 	u8 rtc_ctrl;
218 	unsigned long flags;
219 	int ret = 0;
220 
221 	spin_lock_irqsave(&davinci_rtc_lock, flags);
222 
223 	rtc_ctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL);
224 
225 	switch (cmd) {
226 	case RTC_WIE_ON:
227 		rtc_ctrl |= PRTCSS_RTC_CTRL_WEN | PRTCSS_RTC_CTRL_WDTFLG;
228 		break;
229 	case RTC_WIE_OFF:
230 		rtc_ctrl &= ~PRTCSS_RTC_CTRL_WEN;
231 		break;
232 	default:
233 		ret = -ENOIOCTLCMD;
234 	}
235 
236 	rtcss_write(davinci_rtc, rtc_ctrl, PRTCSS_RTC_CTRL);
237 
238 	spin_unlock_irqrestore(&davinci_rtc_lock, flags);
239 
240 	return ret;
241 }
242 
convertfromdays(u16 days,struct rtc_time * tm)243 static int convertfromdays(u16 days, struct rtc_time *tm)
244 {
245 	int tmp_days, year, mon;
246 
247 	for (year = 2000;; year++) {
248 		tmp_days = rtc_year_days(1, 12, year);
249 		if (days >= tmp_days)
250 			days -= tmp_days;
251 		else {
252 			for (mon = 0;; mon++) {
253 				tmp_days = rtc_month_days(mon, year);
254 				if (days >= tmp_days) {
255 					days -= tmp_days;
256 				} else {
257 					tm->tm_year = year - 1900;
258 					tm->tm_mon = mon;
259 					tm->tm_mday = days + 1;
260 					break;
261 				}
262 			}
263 			break;
264 		}
265 	}
266 	return 0;
267 }
268 
convert2days(u16 * days,struct rtc_time * tm)269 static int convert2days(u16 *days, struct rtc_time *tm)
270 {
271 	int i;
272 	*days = 0;
273 
274 	/* epoch == 1900 */
275 	if (tm->tm_year < 100 || tm->tm_year > 199)
276 		return -EINVAL;
277 
278 	for (i = 2000; i < 1900 + tm->tm_year; i++)
279 		*days += rtc_year_days(1, 12, i);
280 
281 	*days += rtc_year_days(tm->tm_mday, tm->tm_mon, 1900 + tm->tm_year);
282 
283 	return 0;
284 }
285 
davinci_rtc_read_time(struct device * dev,struct rtc_time * tm)286 static int davinci_rtc_read_time(struct device *dev, struct rtc_time *tm)
287 {
288 	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
289 	u16 days = 0;
290 	u8 day0, day1;
291 	unsigned long flags;
292 
293 	spin_lock_irqsave(&davinci_rtc_lock, flags);
294 
295 	davinci_rtcss_calendar_wait(davinci_rtc);
296 	tm->tm_sec = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_SEC));
297 
298 	davinci_rtcss_calendar_wait(davinci_rtc);
299 	tm->tm_min = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_MIN));
300 
301 	davinci_rtcss_calendar_wait(davinci_rtc);
302 	tm->tm_hour = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_HOUR));
303 
304 	davinci_rtcss_calendar_wait(davinci_rtc);
305 	day0 = rtcss_read(davinci_rtc, PRTCSS_RTC_DAY0);
306 
307 	davinci_rtcss_calendar_wait(davinci_rtc);
308 	day1 = rtcss_read(davinci_rtc, PRTCSS_RTC_DAY1);
309 
310 	spin_unlock_irqrestore(&davinci_rtc_lock, flags);
311 
312 	days |= day1;
313 	days <<= 8;
314 	days |= day0;
315 
316 	if (convertfromdays(days, tm) < 0)
317 		return -EINVAL;
318 
319 	return 0;
320 }
321 
davinci_rtc_set_time(struct device * dev,struct rtc_time * tm)322 static int davinci_rtc_set_time(struct device *dev, struct rtc_time *tm)
323 {
324 	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
325 	u16 days;
326 	u8 rtc_cctrl;
327 	unsigned long flags;
328 
329 	if (convert2days(&days, tm) < 0)
330 		return -EINVAL;
331 
332 	spin_lock_irqsave(&davinci_rtc_lock, flags);
333 
334 	davinci_rtcss_calendar_wait(davinci_rtc);
335 	rtcss_write(davinci_rtc, bin2bcd(tm->tm_sec), PRTCSS_RTC_SEC);
336 
337 	davinci_rtcss_calendar_wait(davinci_rtc);
338 	rtcss_write(davinci_rtc, bin2bcd(tm->tm_min), PRTCSS_RTC_MIN);
339 
340 	davinci_rtcss_calendar_wait(davinci_rtc);
341 	rtcss_write(davinci_rtc, bin2bcd(tm->tm_hour), PRTCSS_RTC_HOUR);
342 
343 	davinci_rtcss_calendar_wait(davinci_rtc);
344 	rtcss_write(davinci_rtc, days & 0xFF, PRTCSS_RTC_DAY0);
345 
346 	davinci_rtcss_calendar_wait(davinci_rtc);
347 	rtcss_write(davinci_rtc, (days & 0xFF00) >> 8, PRTCSS_RTC_DAY1);
348 
349 	rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
350 	rtc_cctrl |= PRTCSS_RTC_CCTRL_CAEN;
351 	rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
352 
353 	spin_unlock_irqrestore(&davinci_rtc_lock, flags);
354 
355 	return 0;
356 }
357 
davinci_rtc_alarm_irq_enable(struct device * dev,unsigned int enabled)358 static int davinci_rtc_alarm_irq_enable(struct device *dev,
359 					unsigned int enabled)
360 {
361 	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
362 	unsigned long flags;
363 	u8 rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
364 
365 	spin_lock_irqsave(&davinci_rtc_lock, flags);
366 
367 	if (enabled)
368 		rtc_cctrl |= PRTCSS_RTC_CCTRL_DAEN |
369 			     PRTCSS_RTC_CCTRL_HAEN |
370 			     PRTCSS_RTC_CCTRL_MAEN |
371 			     PRTCSS_RTC_CCTRL_ALMFLG |
372 			     PRTCSS_RTC_CCTRL_AIEN;
373 	else
374 		rtc_cctrl &= ~PRTCSS_RTC_CCTRL_AIEN;
375 
376 	davinci_rtcss_calendar_wait(davinci_rtc);
377 	rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
378 
379 	spin_unlock_irqrestore(&davinci_rtc_lock, flags);
380 
381 	return 0;
382 }
383 
davinci_rtc_read_alarm(struct device * dev,struct rtc_wkalrm * alm)384 static int davinci_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
385 {
386 	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
387 	u16 days = 0;
388 	u8 day0, day1;
389 	unsigned long flags;
390 
391 	alm->time.tm_sec = 0;
392 
393 	spin_lock_irqsave(&davinci_rtc_lock, flags);
394 
395 	davinci_rtcss_calendar_wait(davinci_rtc);
396 	alm->time.tm_min = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_AMIN));
397 
398 	davinci_rtcss_calendar_wait(davinci_rtc);
399 	alm->time.tm_hour = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_AHOUR));
400 
401 	davinci_rtcss_calendar_wait(davinci_rtc);
402 	day0 = rtcss_read(davinci_rtc, PRTCSS_RTC_ADAY0);
403 
404 	davinci_rtcss_calendar_wait(davinci_rtc);
405 	day1 = rtcss_read(davinci_rtc, PRTCSS_RTC_ADAY1);
406 
407 	spin_unlock_irqrestore(&davinci_rtc_lock, flags);
408 	days |= day1;
409 	days <<= 8;
410 	days |= day0;
411 
412 	if (convertfromdays(days, &alm->time) < 0)
413 		return -EINVAL;
414 
415 	alm->pending = !!(rtcss_read(davinci_rtc,
416 			  PRTCSS_RTC_CCTRL) &
417 			PRTCSS_RTC_CCTRL_AIEN);
418 	alm->enabled = alm->pending && device_may_wakeup(dev);
419 
420 	return 0;
421 }
422 
davinci_rtc_set_alarm(struct device * dev,struct rtc_wkalrm * alm)423 static int davinci_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
424 {
425 	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
426 	unsigned long flags;
427 	u16 days;
428 
429 	if (alm->time.tm_mday <= 0 && alm->time.tm_mon < 0
430 	    && alm->time.tm_year < 0) {
431 		struct rtc_time tm;
432 		unsigned long now, then;
433 
434 		davinci_rtc_read_time(dev, &tm);
435 		rtc_tm_to_time(&tm, &now);
436 
437 		alm->time.tm_mday = tm.tm_mday;
438 		alm->time.tm_mon = tm.tm_mon;
439 		alm->time.tm_year = tm.tm_year;
440 		rtc_tm_to_time(&alm->time, &then);
441 
442 		if (then < now) {
443 			rtc_time_to_tm(now + 24 * 60 * 60, &tm);
444 			alm->time.tm_mday = tm.tm_mday;
445 			alm->time.tm_mon = tm.tm_mon;
446 			alm->time.tm_year = tm.tm_year;
447 		}
448 	}
449 
450 	if (convert2days(&days, &alm->time) < 0)
451 		return -EINVAL;
452 
453 	spin_lock_irqsave(&davinci_rtc_lock, flags);
454 
455 	davinci_rtcss_calendar_wait(davinci_rtc);
456 	rtcss_write(davinci_rtc, bin2bcd(alm->time.tm_min), PRTCSS_RTC_AMIN);
457 
458 	davinci_rtcss_calendar_wait(davinci_rtc);
459 	rtcss_write(davinci_rtc, bin2bcd(alm->time.tm_hour), PRTCSS_RTC_AHOUR);
460 
461 	davinci_rtcss_calendar_wait(davinci_rtc);
462 	rtcss_write(davinci_rtc, days & 0xFF, PRTCSS_RTC_ADAY0);
463 
464 	davinci_rtcss_calendar_wait(davinci_rtc);
465 	rtcss_write(davinci_rtc, (days & 0xFF00) >> 8, PRTCSS_RTC_ADAY1);
466 
467 	spin_unlock_irqrestore(&davinci_rtc_lock, flags);
468 
469 	return 0;
470 }
471 
472 static const struct rtc_class_ops davinci_rtc_ops = {
473 	.ioctl			= davinci_rtc_ioctl,
474 	.read_time		= davinci_rtc_read_time,
475 	.set_time		= davinci_rtc_set_time,
476 	.alarm_irq_enable	= davinci_rtc_alarm_irq_enable,
477 	.read_alarm		= davinci_rtc_read_alarm,
478 	.set_alarm		= davinci_rtc_set_alarm,
479 };
480 
davinci_rtc_probe(struct platform_device * pdev)481 static int __init davinci_rtc_probe(struct platform_device *pdev)
482 {
483 	struct device *dev = &pdev->dev;
484 	struct davinci_rtc *davinci_rtc;
485 	struct resource *res;
486 	int ret = 0;
487 
488 	davinci_rtc = devm_kzalloc(&pdev->dev, sizeof(struct davinci_rtc), GFP_KERNEL);
489 	if (!davinci_rtc)
490 		return -ENOMEM;
491 
492 	davinci_rtc->irq = platform_get_irq(pdev, 0);
493 	if (davinci_rtc->irq < 0) {
494 		dev_err(dev, "no RTC irq\n");
495 		return davinci_rtc->irq;
496 	}
497 
498 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
499 	davinci_rtc->base = devm_ioremap_resource(dev, res);
500 	if (IS_ERR(davinci_rtc->base))
501 		return PTR_ERR(davinci_rtc->base);
502 
503 	platform_set_drvdata(pdev, davinci_rtc);
504 
505 	davinci_rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
506 				    &davinci_rtc_ops, THIS_MODULE);
507 	if (IS_ERR(davinci_rtc->rtc)) {
508 		dev_err(dev, "unable to register RTC device, err %d\n",
509 				ret);
510 		return PTR_ERR(davinci_rtc->rtc);
511 	}
512 
513 	rtcif_write(davinci_rtc, PRTCIF_INTFLG_RTCSS, PRTCIF_INTFLG);
514 	rtcif_write(davinci_rtc, 0, PRTCIF_INTEN);
515 	rtcss_write(davinci_rtc, 0, PRTCSS_RTC_INTC_EXTENA1);
516 
517 	rtcss_write(davinci_rtc, 0, PRTCSS_RTC_CTRL);
518 	rtcss_write(davinci_rtc, 0, PRTCSS_RTC_CCTRL);
519 
520 	ret = devm_request_irq(dev, davinci_rtc->irq, davinci_rtc_interrupt,
521 			  0, "davinci_rtc", davinci_rtc);
522 	if (ret < 0) {
523 		dev_err(dev, "unable to register davinci RTC interrupt\n");
524 		return ret;
525 	}
526 
527 	/* Enable interrupts */
528 	rtcif_write(davinci_rtc, PRTCIF_INTEN_RTCSS, PRTCIF_INTEN);
529 	rtcss_write(davinci_rtc, PRTCSS_RTC_INTC_EXTENA1_MASK,
530 			    PRTCSS_RTC_INTC_EXTENA1);
531 
532 	rtcss_write(davinci_rtc, PRTCSS_RTC_CCTRL_CAEN, PRTCSS_RTC_CCTRL);
533 
534 	device_init_wakeup(&pdev->dev, 0);
535 
536 	return 0;
537 }
538 
davinci_rtc_remove(struct platform_device * pdev)539 static int __exit davinci_rtc_remove(struct platform_device *pdev)
540 {
541 	struct davinci_rtc *davinci_rtc = platform_get_drvdata(pdev);
542 
543 	device_init_wakeup(&pdev->dev, 0);
544 
545 	rtcif_write(davinci_rtc, 0, PRTCIF_INTEN);
546 
547 	return 0;
548 }
549 
550 static struct platform_driver davinci_rtc_driver = {
551 	.remove		= __exit_p(davinci_rtc_remove),
552 	.driver		= {
553 		.name = "rtc_davinci",
554 	},
555 };
556 
557 module_platform_driver_probe(davinci_rtc_driver, davinci_rtc_probe);
558 
559 MODULE_AUTHOR("Miguel Aguilar <miguel.aguilar@ridgerun.com>");
560 MODULE_DESCRIPTION("Texas Instruments DaVinci PRTC Driver");
561 MODULE_LICENSE("GPL");
562