2 * DaVinci Power Management and Real Time Clock Driver for TI platforms
4 * Copyright (C) 2009 Texas Instruments, Inc
6 * Author: Miguel Aguilar <miguel.aguilar@ridgerun.com>
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.
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.
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
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>
32 #include <linux/slab.h>
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 )
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
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)
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 \
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)
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)
95 /* PRTCSS_RTC_INTC_EXTENA1 */
96 #define PRTCSS_RTC_INTC_EXTENA1_MASK (0x07)
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)
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)
117 static DEFINE_SPINLOCK(davinci_rtc_lock
);
120 struct rtc_device
*rtc
;
122 resource_size_t pbase
;
127 static inline void rtcif_write(struct davinci_rtc
*davinci_rtc
,
130 writel(val
, davinci_rtc
->base
+ addr
);
133 static inline u32
rtcif_read(struct davinci_rtc
*davinci_rtc
, u32 addr
)
135 return readl(davinci_rtc
->base
+ addr
);
138 static inline void rtcif_wait(struct davinci_rtc
*davinci_rtc
)
140 while (rtcif_read(davinci_rtc
, PRTCIF_CTLR
) & PRTCIF_CTLR_BUSY
)
144 static inline void rtcss_write(struct davinci_rtc
*davinci_rtc
,
145 unsigned long val
, u8 addr
)
147 rtcif_wait(davinci_rtc
);
149 rtcif_write(davinci_rtc
, PRTCIF_CTLR_BENL_LSB
| addr
, PRTCIF_CTLR
);
150 rtcif_write(davinci_rtc
, val
, PRTCIF_LDATA
);
152 rtcif_wait(davinci_rtc
);
155 static inline u8
rtcss_read(struct davinci_rtc
*davinci_rtc
, u8 addr
)
157 rtcif_wait(davinci_rtc
);
159 rtcif_write(davinci_rtc
, PRTCIF_CTLR_DIR
| PRTCIF_CTLR_BENL_LSB
| addr
,
162 rtcif_wait(davinci_rtc
);
164 return rtcif_read(davinci_rtc
, PRTCIF_LDATA
);
167 static inline void davinci_rtcss_calendar_wait(struct davinci_rtc
*davinci_rtc
)
169 while (rtcss_read(davinci_rtc
, PRTCSS_RTC_CCTRL
) &
170 PRTCSS_RTC_CCTRL_CALBUSY
)
174 static irqreturn_t
davinci_rtc_interrupt(int irq
, void *class_dev
)
176 struct davinci_rtc
*davinci_rtc
= class_dev
;
177 unsigned long events
= 0;
180 u8 rtc_ctrl
, rtc_cctrl
;
183 irq_flg
= rtcif_read(davinci_rtc
, PRTCIF_INTFLG
) &
186 alm_irq
= rtcss_read(davinci_rtc
, PRTCSS_RTC_CCTRL
) &
187 PRTCSS_RTC_CCTRL_ALMFLG
;
189 tmr_irq
= rtcss_read(davinci_rtc
, PRTCSS_RTC_CTRL
) &
190 PRTCSS_RTC_CTRL_TMRFLG
;
194 events
|= RTC_IRQF
| RTC_AF
;
195 rtc_cctrl
= rtcss_read(davinci_rtc
, PRTCSS_RTC_CCTRL
);
196 rtc_cctrl
|= PRTCSS_RTC_CCTRL_ALMFLG
;
197 rtcss_write(davinci_rtc
, rtc_cctrl
, PRTCSS_RTC_CCTRL
);
198 } else if (tmr_irq
) {
199 events
|= RTC_IRQF
| RTC_PF
;
200 rtc_ctrl
= rtcss_read(davinci_rtc
, PRTCSS_RTC_CTRL
);
201 rtc_ctrl
|= PRTCSS_RTC_CTRL_TMRFLG
;
202 rtcss_write(davinci_rtc
, rtc_ctrl
, PRTCSS_RTC_CTRL
);
205 rtcif_write(davinci_rtc
, PRTCIF_INTFLG_RTCSS
,
207 rtc_update_irq(davinci_rtc
->rtc
, 1, events
);
216 davinci_rtc_ioctl(struct device
*dev
, unsigned int cmd
, unsigned long arg
)
218 struct davinci_rtc
*davinci_rtc
= dev_get_drvdata(dev
);
223 spin_lock_irqsave(&davinci_rtc_lock
, flags
);
225 rtc_ctrl
= rtcss_read(davinci_rtc
, PRTCSS_RTC_CTRL
);
229 rtc_ctrl
|= PRTCSS_RTC_CTRL_WEN
| PRTCSS_RTC_CTRL_WDTFLG
;
232 rtc_ctrl
&= ~PRTCSS_RTC_CTRL_WEN
;
238 rtcss_write(davinci_rtc
, rtc_ctrl
, PRTCSS_RTC_CTRL
);
240 spin_unlock_irqrestore(&davinci_rtc_lock
, flags
);
245 static int convertfromdays(u16 days
, struct rtc_time
*tm
)
247 int tmp_days
, year
, mon
;
249 for (year
= 2000;; year
++) {
250 tmp_days
= rtc_year_days(1, 12, year
);
251 if (days
>= tmp_days
)
254 for (mon
= 0;; mon
++) {
255 tmp_days
= rtc_month_days(mon
, year
);
256 if (days
>= tmp_days
) {
259 tm
->tm_year
= year
- 1900;
261 tm
->tm_mday
= days
+ 1;
271 static int convert2days(u16
*days
, struct rtc_time
*tm
)
277 if (tm
->tm_year
< 100 || tm
->tm_year
> 199)
280 for (i
= 2000; i
< 1900 + tm
->tm_year
; i
++)
281 *days
+= rtc_year_days(1, 12, i
);
283 *days
+= rtc_year_days(tm
->tm_mday
, tm
->tm_mon
, 1900 + tm
->tm_year
);
288 static int davinci_rtc_read_time(struct device
*dev
, struct rtc_time
*tm
)
290 struct davinci_rtc
*davinci_rtc
= dev_get_drvdata(dev
);
295 spin_lock_irqsave(&davinci_rtc_lock
, flags
);
297 davinci_rtcss_calendar_wait(davinci_rtc
);
298 tm
->tm_sec
= bcd2bin(rtcss_read(davinci_rtc
, PRTCSS_RTC_SEC
));
300 davinci_rtcss_calendar_wait(davinci_rtc
);
301 tm
->tm_min
= bcd2bin(rtcss_read(davinci_rtc
, PRTCSS_RTC_MIN
));
303 davinci_rtcss_calendar_wait(davinci_rtc
);
304 tm
->tm_hour
= bcd2bin(rtcss_read(davinci_rtc
, PRTCSS_RTC_HOUR
));
306 davinci_rtcss_calendar_wait(davinci_rtc
);
307 day0
= rtcss_read(davinci_rtc
, PRTCSS_RTC_DAY0
);
309 davinci_rtcss_calendar_wait(davinci_rtc
);
310 day1
= rtcss_read(davinci_rtc
, PRTCSS_RTC_DAY1
);
312 spin_unlock_irqrestore(&davinci_rtc_lock
, flags
);
318 if (convertfromdays(days
, tm
) < 0)
324 static int davinci_rtc_set_time(struct device
*dev
, struct rtc_time
*tm
)
326 struct davinci_rtc
*davinci_rtc
= dev_get_drvdata(dev
);
331 if (convert2days(&days
, tm
) < 0)
334 spin_lock_irqsave(&davinci_rtc_lock
, flags
);
336 davinci_rtcss_calendar_wait(davinci_rtc
);
337 rtcss_write(davinci_rtc
, bin2bcd(tm
->tm_sec
), PRTCSS_RTC_SEC
);
339 davinci_rtcss_calendar_wait(davinci_rtc
);
340 rtcss_write(davinci_rtc
, bin2bcd(tm
->tm_min
), PRTCSS_RTC_MIN
);
342 davinci_rtcss_calendar_wait(davinci_rtc
);
343 rtcss_write(davinci_rtc
, bin2bcd(tm
->tm_hour
), PRTCSS_RTC_HOUR
);
345 davinci_rtcss_calendar_wait(davinci_rtc
);
346 rtcss_write(davinci_rtc
, days
& 0xFF, PRTCSS_RTC_DAY0
);
348 davinci_rtcss_calendar_wait(davinci_rtc
);
349 rtcss_write(davinci_rtc
, (days
& 0xFF00) >> 8, PRTCSS_RTC_DAY1
);
351 rtc_cctrl
= rtcss_read(davinci_rtc
, PRTCSS_RTC_CCTRL
);
352 rtc_cctrl
|= PRTCSS_RTC_CCTRL_CAEN
;
353 rtcss_write(davinci_rtc
, rtc_cctrl
, PRTCSS_RTC_CCTRL
);
355 spin_unlock_irqrestore(&davinci_rtc_lock
, flags
);
360 static int davinci_rtc_alarm_irq_enable(struct device
*dev
,
361 unsigned int enabled
)
363 struct davinci_rtc
*davinci_rtc
= dev_get_drvdata(dev
);
365 u8 rtc_cctrl
= rtcss_read(davinci_rtc
, PRTCSS_RTC_CCTRL
);
367 spin_lock_irqsave(&davinci_rtc_lock
, flags
);
370 rtc_cctrl
|= PRTCSS_RTC_CCTRL_DAEN
|
371 PRTCSS_RTC_CCTRL_HAEN
|
372 PRTCSS_RTC_CCTRL_MAEN
|
373 PRTCSS_RTC_CCTRL_ALMFLG
|
374 PRTCSS_RTC_CCTRL_AIEN
;
376 rtc_cctrl
&= ~PRTCSS_RTC_CCTRL_AIEN
;
378 davinci_rtcss_calendar_wait(davinci_rtc
);
379 rtcss_write(davinci_rtc
, rtc_cctrl
, PRTCSS_RTC_CCTRL
);
381 spin_unlock_irqrestore(&davinci_rtc_lock
, flags
);
386 static int davinci_rtc_read_alarm(struct device
*dev
, struct rtc_wkalrm
*alm
)
388 struct davinci_rtc
*davinci_rtc
= dev_get_drvdata(dev
);
393 spin_lock_irqsave(&davinci_rtc_lock
, flags
);
395 davinci_rtcss_calendar_wait(davinci_rtc
);
396 alm
->time
.tm_min
= bcd2bin(rtcss_read(davinci_rtc
, PRTCSS_RTC_AMIN
));
398 davinci_rtcss_calendar_wait(davinci_rtc
);
399 alm
->time
.tm_hour
= bcd2bin(rtcss_read(davinci_rtc
, PRTCSS_RTC_AHOUR
));
401 davinci_rtcss_calendar_wait(davinci_rtc
);
402 day0
= rtcss_read(davinci_rtc
, PRTCSS_RTC_ADAY0
);
404 davinci_rtcss_calendar_wait(davinci_rtc
);
405 day1
= rtcss_read(davinci_rtc
, PRTCSS_RTC_ADAY1
);
407 spin_unlock_irqrestore(&davinci_rtc_lock
, flags
);
412 if (convertfromdays(days
, &alm
->time
) < 0)
415 alm
->pending
= !!(rtcss_read(davinci_rtc
,
417 PRTCSS_RTC_CCTRL_AIEN
);
418 alm
->enabled
= alm
->pending
&& device_may_wakeup(dev
);
423 static int davinci_rtc_set_alarm(struct device
*dev
, struct rtc_wkalrm
*alm
)
425 struct davinci_rtc
*davinci_rtc
= dev_get_drvdata(dev
);
429 if (alm
->time
.tm_mday
<= 0 && alm
->time
.tm_mon
< 0
430 && alm
->time
.tm_year
< 0) {
432 unsigned long now
, then
;
434 davinci_rtc_read_time(dev
, &tm
);
435 rtc_tm_to_time(&tm
, &now
);
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
);
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
;
450 if (convert2days(&days
, &alm
->time
) < 0)
453 spin_lock_irqsave(&davinci_rtc_lock
, flags
);
455 davinci_rtcss_calendar_wait(davinci_rtc
);
456 rtcss_write(davinci_rtc
, bin2bcd(alm
->time
.tm_min
), PRTCSS_RTC_AMIN
);
458 davinci_rtcss_calendar_wait(davinci_rtc
);
459 rtcss_write(davinci_rtc
, bin2bcd(alm
->time
.tm_hour
), PRTCSS_RTC_AHOUR
);
461 davinci_rtcss_calendar_wait(davinci_rtc
);
462 rtcss_write(davinci_rtc
, days
& 0xFF, PRTCSS_RTC_ADAY0
);
464 davinci_rtcss_calendar_wait(davinci_rtc
);
465 rtcss_write(davinci_rtc
, (days
& 0xFF00) >> 8, PRTCSS_RTC_ADAY1
);
467 spin_unlock_irqrestore(&davinci_rtc_lock
, flags
);
472 static 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
,
481 static int __init
davinci_rtc_probe(struct platform_device
*pdev
)
483 struct device
*dev
= &pdev
->dev
;
484 struct davinci_rtc
*davinci_rtc
;
485 struct resource
*res
, *mem
;
488 davinci_rtc
= devm_kzalloc(&pdev
->dev
, sizeof(struct davinci_rtc
), GFP_KERNEL
);
490 dev_dbg(dev
, "could not allocate memory for private data\n");
494 davinci_rtc
->irq
= platform_get_irq(pdev
, 0);
495 if (davinci_rtc
->irq
< 0) {
496 dev_err(dev
, "no RTC irq\n");
497 return davinci_rtc
->irq
;
500 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
502 dev_err(dev
, "no mem resource\n");
506 davinci_rtc
->pbase
= res
->start
;
507 davinci_rtc
->base_size
= resource_size(res
);
509 mem
= request_mem_region(davinci_rtc
->pbase
, davinci_rtc
->base_size
,
512 dev_err(dev
, "RTC registers at %08x are not free\n",
517 davinci_rtc
->base
= ioremap(davinci_rtc
->pbase
, davinci_rtc
->base_size
);
518 if (!davinci_rtc
->base
) {
519 dev_err(dev
, "unable to ioremap MEM resource\n");
524 platform_set_drvdata(pdev
, davinci_rtc
);
526 davinci_rtc
->rtc
= rtc_device_register(pdev
->name
, &pdev
->dev
,
527 &davinci_rtc_ops
, THIS_MODULE
);
528 if (IS_ERR(davinci_rtc
->rtc
)) {
529 ret
= PTR_ERR(davinci_rtc
->rtc
);
530 dev_err(dev
, "unable to register RTC device, err %d\n",
535 rtcif_write(davinci_rtc
, PRTCIF_INTFLG_RTCSS
, PRTCIF_INTFLG
);
536 rtcif_write(davinci_rtc
, 0, PRTCIF_INTEN
);
537 rtcss_write(davinci_rtc
, 0, PRTCSS_RTC_INTC_EXTENA1
);
539 rtcss_write(davinci_rtc
, 0, PRTCSS_RTC_CTRL
);
540 rtcss_write(davinci_rtc
, 0, PRTCSS_RTC_CCTRL
);
542 ret
= request_irq(davinci_rtc
->irq
, davinci_rtc_interrupt
,
543 0, "davinci_rtc", davinci_rtc
);
545 dev_err(dev
, "unable to register davinci RTC interrupt\n");
549 /* Enable interrupts */
550 rtcif_write(davinci_rtc
, PRTCIF_INTEN_RTCSS
, PRTCIF_INTEN
);
551 rtcss_write(davinci_rtc
, PRTCSS_RTC_INTC_EXTENA1_MASK
,
552 PRTCSS_RTC_INTC_EXTENA1
);
554 rtcss_write(davinci_rtc
, PRTCSS_RTC_CCTRL_CAEN
, PRTCSS_RTC_CCTRL
);
556 device_init_wakeup(&pdev
->dev
, 0);
561 rtc_device_unregister(davinci_rtc
->rtc
);
563 platform_set_drvdata(pdev
, NULL
);
564 iounmap(davinci_rtc
->base
);
566 release_mem_region(davinci_rtc
->pbase
, davinci_rtc
->base_size
);
570 static int davinci_rtc_remove(struct platform_device
*pdev
)
572 struct davinci_rtc
*davinci_rtc
= platform_get_drvdata(pdev
);
574 device_init_wakeup(&pdev
->dev
, 0);
576 rtcif_write(davinci_rtc
, 0, PRTCIF_INTEN
);
578 free_irq(davinci_rtc
->irq
, davinci_rtc
);
580 rtc_device_unregister(davinci_rtc
->rtc
);
582 iounmap(davinci_rtc
->base
);
583 release_mem_region(davinci_rtc
->pbase
, davinci_rtc
->base_size
);
585 platform_set_drvdata(pdev
, NULL
);
590 static struct platform_driver davinci_rtc_driver
= {
591 .probe
= davinci_rtc_probe
,
592 .remove
= davinci_rtc_remove
,
594 .name
= "rtc_davinci",
595 .owner
= THIS_MODULE
,
599 static int __init
rtc_init(void)
601 return platform_driver_probe(&davinci_rtc_driver
, davinci_rtc_probe
);
603 module_init(rtc_init
);
605 static void __exit
rtc_exit(void)
607 platform_driver_unregister(&davinci_rtc_driver
);
609 module_exit(rtc_exit
);
611 MODULE_AUTHOR("Miguel Aguilar <miguel.aguilar@ridgerun.com>");
612 MODULE_DESCRIPTION("Texas Instruments DaVinci PRTC Driver");
613 MODULE_LICENSE("GPL");