2 * Real Time Clock interface for XScale PXA27x and PXA3xx
4 * Copyright (C) 2008 Robert Jarzmik
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include <linux/init.h>
23 #include <linux/platform_device.h>
24 #include <linux/module.h>
25 #include <linux/rtc.h>
26 #include <linux/seq_file.h>
27 #include <linux/interrupt.h>
30 #include <mach/hardware.h>
32 #define TIMER_FREQ CLOCK_TICK_RATE
33 #define RTC_DEF_DIVIDER (32768 - 1)
34 #define RTC_DEF_TRIM 0
35 #define MAXFREQ_PERIODIC 1000
38 * PXA Registers and bits definitions
40 #define RTSR_PICE (1 << 15) /* Periodic interrupt count enable */
41 #define RTSR_PIALE (1 << 14) /* Periodic interrupt Alarm enable */
42 #define RTSR_PIAL (1 << 13) /* Periodic interrupt detected */
43 #define RTSR_SWALE2 (1 << 11) /* RTC stopwatch alarm2 enable */
44 #define RTSR_SWAL2 (1 << 10) /* RTC stopwatch alarm2 detected */
45 #define RTSR_SWALE1 (1 << 9) /* RTC stopwatch alarm1 enable */
46 #define RTSR_SWAL1 (1 << 8) /* RTC stopwatch alarm1 detected */
47 #define RTSR_RDALE2 (1 << 7) /* RTC alarm2 enable */
48 #define RTSR_RDAL2 (1 << 6) /* RTC alarm2 detected */
49 #define RTSR_RDALE1 (1 << 5) /* RTC alarm1 enable */
50 #define RTSR_RDAL1 (1 << 4) /* RTC alarm1 detected */
51 #define RTSR_HZE (1 << 3) /* HZ interrupt enable */
52 #define RTSR_ALE (1 << 2) /* RTC alarm interrupt enable */
53 #define RTSR_HZ (1 << 1) /* HZ rising-edge detected */
54 #define RTSR_AL (1 << 0) /* RTC alarm detected */
55 #define RTSR_TRIG_MASK (RTSR_AL | RTSR_HZ | RTSR_RDAL1 | RTSR_RDAL2\
56 | RTSR_SWAL1 | RTSR_SWAL2)
58 #define RYxR_YEAR_MASK (0xfff << RYxR_YEAR_S)
59 #define RYxR_MONTH_S 5
60 #define RYxR_MONTH_MASK (0xf << RYxR_MONTH_S)
61 #define RYxR_DAY_MASK 0x1f
62 #define RDxR_HOUR_S 12
63 #define RDxR_HOUR_MASK (0x1f << RDxR_HOUR_S)
65 #define RDxR_MIN_MASK (0x3f << RDxR_MIN_S)
66 #define RDxR_SEC_MASK 0x3f
77 #define rtc_readl(pxa_rtc, reg) \
78 __raw_readl((pxa_rtc)->base + (reg))
79 #define rtc_writel(pxa_rtc, reg, value) \
80 __raw_writel((value), (pxa_rtc)->base + (reg))
83 struct resource
*ress
;
87 struct rtc_device
*rtc
;
88 spinlock_t lock
; /* Protects this structure */
89 struct rtc_time rtc_alarm
;
92 static u32
ryxr_calc(struct rtc_time
*tm
)
94 return ((tm
->tm_year
+ 1900) << RYxR_YEAR_S
)
95 | ((tm
->tm_mon
+ 1) << RYxR_MONTH_S
)
99 static u32
rdxr_calc(struct rtc_time
*tm
)
101 return (tm
->tm_hour
<< RDxR_HOUR_S
) | (tm
->tm_min
<< RDxR_MIN_S
)
105 static void tm_calc(u32 rycr
, u32 rdcr
, struct rtc_time
*tm
)
107 tm
->tm_year
= ((rycr
& RYxR_YEAR_MASK
) >> RYxR_YEAR_S
) - 1900;
108 tm
->tm_mon
= (((rycr
& RYxR_MONTH_MASK
) >> RYxR_MONTH_S
)) - 1;
109 tm
->tm_mday
= (rycr
& RYxR_DAY_MASK
);
110 tm
->tm_hour
= (rdcr
& RDxR_HOUR_MASK
) >> RDxR_HOUR_S
;
111 tm
->tm_min
= (rdcr
& RDxR_MIN_MASK
) >> RDxR_MIN_S
;
112 tm
->tm_sec
= rdcr
& RDxR_SEC_MASK
;
115 static void rtsr_clear_bits(struct pxa_rtc
*pxa_rtc
, u32 mask
)
119 rtsr
= rtc_readl(pxa_rtc
, RTSR
);
120 rtsr
&= ~RTSR_TRIG_MASK
;
122 rtc_writel(pxa_rtc
, RTSR
, rtsr
);
125 static void rtsr_set_bits(struct pxa_rtc
*pxa_rtc
, u32 mask
)
129 rtsr
= rtc_readl(pxa_rtc
, RTSR
);
130 rtsr
&= ~RTSR_TRIG_MASK
;
132 rtc_writel(pxa_rtc
, RTSR
, rtsr
);
135 static irqreturn_t
pxa_rtc_irq(int irq
, void *dev_id
)
137 struct platform_device
*pdev
= to_platform_device(dev_id
);
138 struct pxa_rtc
*pxa_rtc
= platform_get_drvdata(pdev
);
140 unsigned long events
= 0;
142 spin_lock(&pxa_rtc
->lock
);
144 /* clear interrupt sources */
145 rtsr
= rtc_readl(pxa_rtc
, RTSR
);
146 rtc_writel(pxa_rtc
, RTSR
, rtsr
);
148 /* temporary disable rtc interrupts */
149 rtsr_clear_bits(pxa_rtc
, RTSR_RDALE1
| RTSR_PIALE
| RTSR_HZE
);
151 /* clear alarm interrupt if it has occurred */
152 if (rtsr
& RTSR_RDAL1
)
153 rtsr
&= ~RTSR_RDALE1
;
155 /* update irq data & counter */
156 if (rtsr
& RTSR_RDAL1
)
157 events
|= RTC_AF
| RTC_IRQF
;
159 events
|= RTC_UF
| RTC_IRQF
;
160 if (rtsr
& RTSR_PIAL
)
161 events
|= RTC_PF
| RTC_IRQF
;
163 rtc_update_irq(pxa_rtc
->rtc
, 1, events
);
165 /* enable back rtc interrupts */
166 rtc_writel(pxa_rtc
, RTSR
, rtsr
& ~RTSR_TRIG_MASK
);
168 spin_unlock(&pxa_rtc
->lock
);
172 static int pxa_rtc_open(struct device
*dev
)
174 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
177 ret
= request_irq(pxa_rtc
->irq_1Hz
, pxa_rtc_irq
, IRQF_DISABLED
,
180 dev_err(dev
, "can't get irq %i, err %d\n", pxa_rtc
->irq_1Hz
,
184 ret
= request_irq(pxa_rtc
->irq_Alrm
, pxa_rtc_irq
, IRQF_DISABLED
,
187 dev_err(dev
, "can't get irq %i, err %d\n", pxa_rtc
->irq_Alrm
,
195 free_irq(pxa_rtc
->irq_1Hz
, dev
);
200 static void pxa_rtc_release(struct device
*dev
)
202 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
204 spin_lock_irq(&pxa_rtc
->lock
);
205 rtsr_clear_bits(pxa_rtc
, RTSR_PIALE
| RTSR_RDALE1
| RTSR_HZE
);
206 spin_unlock_irq(&pxa_rtc
->lock
);
208 free_irq(pxa_rtc
->irq_Alrm
, dev
);
209 free_irq(pxa_rtc
->irq_1Hz
, dev
);
212 static int pxa_periodic_irq_set_freq(struct device
*dev
, int freq
)
214 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
217 if (freq
< 1 || freq
> MAXFREQ_PERIODIC
)
220 period_ms
= 1000 / freq
;
221 rtc_writel(pxa_rtc
, PIAR
, period_ms
);
226 static int pxa_periodic_irq_set_state(struct device
*dev
, int enabled
)
228 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
231 rtsr_set_bits(pxa_rtc
, RTSR_PIALE
| RTSR_PICE
);
233 rtsr_clear_bits(pxa_rtc
, RTSR_PIALE
| RTSR_PICE
);
238 static int pxa_rtc_ioctl(struct device
*dev
, unsigned int cmd
,
241 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
244 spin_lock_irq(&pxa_rtc
->lock
);
247 rtsr_clear_bits(pxa_rtc
, RTSR_RDALE1
);
250 rtsr_set_bits(pxa_rtc
, RTSR_RDALE1
);
253 rtsr_clear_bits(pxa_rtc
, RTSR_HZE
);
256 rtsr_set_bits(pxa_rtc
, RTSR_HZE
);
262 spin_unlock_irq(&pxa_rtc
->lock
);
266 static int pxa_rtc_read_time(struct device
*dev
, struct rtc_time
*tm
)
268 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
271 rycr
= rtc_readl(pxa_rtc
, RYCR
);
272 rdcr
= rtc_readl(pxa_rtc
, RDCR
);
274 tm_calc(rycr
, rdcr
, tm
);
278 static int pxa_rtc_set_time(struct device
*dev
, struct rtc_time
*tm
)
280 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
282 rtc_writel(pxa_rtc
, RYCR
, ryxr_calc(tm
));
283 rtc_writel(pxa_rtc
, RDCR
, rdxr_calc(tm
));
288 static int pxa_rtc_read_alarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
290 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
291 u32 rtsr
, ryar
, rdar
;
293 ryar
= rtc_readl(pxa_rtc
, RYAR1
);
294 rdar
= rtc_readl(pxa_rtc
, RDAR1
);
295 tm_calc(ryar
, rdar
, &alrm
->time
);
297 rtsr
= rtc_readl(pxa_rtc
, RTSR
);
298 alrm
->enabled
= (rtsr
& RTSR_RDALE1
) ? 1 : 0;
299 alrm
->pending
= (rtsr
& RTSR_RDAL1
) ? 1 : 0;
303 static int pxa_rtc_set_alarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
305 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
308 spin_lock_irq(&pxa_rtc
->lock
);
310 rtc_writel(pxa_rtc
, RYAR1
, ryxr_calc(&alrm
->time
));
311 rtc_writel(pxa_rtc
, RDAR1
, rdxr_calc(&alrm
->time
));
313 rtsr
= rtc_readl(pxa_rtc
, RTSR
);
317 rtsr
&= ~RTSR_RDALE1
;
318 rtc_writel(pxa_rtc
, RTSR
, rtsr
);
320 spin_unlock_irq(&pxa_rtc
->lock
);
325 static int pxa_rtc_proc(struct device
*dev
, struct seq_file
*seq
)
327 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
329 seq_printf(seq
, "trim/divider\t: 0x%08x\n", rtc_readl(pxa_rtc
, RTTR
));
330 seq_printf(seq
, "update_IRQ\t: %s\n",
331 (rtc_readl(pxa_rtc
, RTSR
) & RTSR_HZE
) ? "yes" : "no");
332 seq_printf(seq
, "periodic_IRQ\t: %s\n",
333 (rtc_readl(pxa_rtc
, RTSR
) & RTSR_PIALE
) ? "yes" : "no");
334 seq_printf(seq
, "periodic_freq\t: %u\n", rtc_readl(pxa_rtc
, PIAR
));
339 static const struct rtc_class_ops pxa_rtc_ops
= {
340 .open
= pxa_rtc_open
,
341 .release
= pxa_rtc_release
,
342 .ioctl
= pxa_rtc_ioctl
,
343 .read_time
= pxa_rtc_read_time
,
344 .set_time
= pxa_rtc_set_time
,
345 .read_alarm
= pxa_rtc_read_alarm
,
346 .set_alarm
= pxa_rtc_set_alarm
,
347 .proc
= pxa_rtc_proc
,
348 .irq_set_state
= pxa_periodic_irq_set_state
,
349 .irq_set_freq
= pxa_periodic_irq_set_freq
,
352 static int __init
pxa_rtc_probe(struct platform_device
*pdev
)
354 struct device
*dev
= &pdev
->dev
;
355 struct pxa_rtc
*pxa_rtc
;
359 pxa_rtc
= kzalloc(sizeof(struct pxa_rtc
), GFP_KERNEL
);
363 spin_lock_init(&pxa_rtc
->lock
);
364 platform_set_drvdata(pdev
, pxa_rtc
);
367 pxa_rtc
->ress
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
368 if (!pxa_rtc
->ress
) {
369 dev_err(dev
, "No I/O memory resource defined\n");
373 pxa_rtc
->irq_1Hz
= platform_get_irq(pdev
, 0);
374 if (pxa_rtc
->irq_1Hz
< 0) {
375 dev_err(dev
, "No 1Hz IRQ resource defined\n");
378 pxa_rtc
->irq_Alrm
= platform_get_irq(pdev
, 1);
379 if (pxa_rtc
->irq_Alrm
< 0) {
380 dev_err(dev
, "No alarm IRQ resource defined\n");
385 pxa_rtc
->base
= ioremap(pxa_rtc
->ress
->start
,
386 resource_size(pxa_rtc
->ress
));
387 if (!pxa_rtc
->base
) {
388 dev_err(&pdev
->dev
, "Unable to map pxa RTC I/O memory\n");
393 * If the clock divider is uninitialized then reset it to the
394 * default value to get the 1Hz clock.
396 if (rtc_readl(pxa_rtc
, RTTR
) == 0) {
397 rttr
= RTC_DEF_DIVIDER
+ (RTC_DEF_TRIM
<< 16);
398 rtc_writel(pxa_rtc
, RTTR
, rttr
);
399 dev_warn(dev
, "warning: initializing default clock"
400 " divider/trim value\n");
403 rtsr_clear_bits(pxa_rtc
, RTSR_PIALE
| RTSR_RDALE1
| RTSR_HZE
);
405 pxa_rtc
->rtc
= rtc_device_register("pxa-rtc", &pdev
->dev
, &pxa_rtc_ops
,
407 ret
= PTR_ERR(pxa_rtc
->rtc
);
408 if (IS_ERR(pxa_rtc
->rtc
)) {
409 dev_err(dev
, "Failed to register RTC device -> %d\n", ret
);
413 device_init_wakeup(dev
, 1);
418 iounmap(pxa_rtc
->base
);
425 static int __exit
pxa_rtc_remove(struct platform_device
*pdev
)
427 struct pxa_rtc
*pxa_rtc
= platform_get_drvdata(pdev
);
429 rtc_device_unregister(pxa_rtc
->rtc
);
431 spin_lock_irq(&pxa_rtc
->lock
);
432 iounmap(pxa_rtc
->base
);
433 spin_unlock_irq(&pxa_rtc
->lock
);
441 static int pxa_rtc_suspend(struct platform_device
*pdev
, pm_message_t state
)
443 struct pxa_rtc
*pxa_rtc
= platform_get_drvdata(pdev
);
445 if (device_may_wakeup(&pdev
->dev
))
446 enable_irq_wake(pxa_rtc
->irq_Alrm
);
450 static int pxa_rtc_resume(struct platform_device
*pdev
)
452 struct pxa_rtc
*pxa_rtc
= platform_get_drvdata(pdev
);
454 if (device_may_wakeup(&pdev
->dev
))
455 disable_irq_wake(pxa_rtc
->irq_Alrm
);
459 #define pxa_rtc_suspend NULL
460 #define pxa_rtc_resume NULL
463 static struct platform_driver pxa_rtc_driver
= {
464 .remove
= __exit_p(pxa_rtc_remove
),
465 .suspend
= pxa_rtc_suspend
,
466 .resume
= pxa_rtc_resume
,
472 static int __init
pxa_rtc_init(void)
474 if (cpu_is_pxa27x() || cpu_is_pxa3xx())
475 return platform_driver_probe(&pxa_rtc_driver
, pxa_rtc_probe
);
480 static void __exit
pxa_rtc_exit(void)
482 platform_driver_unregister(&pxa_rtc_driver
);
485 module_init(pxa_rtc_init
);
486 module_exit(pxa_rtc_exit
);
488 MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
489 MODULE_DESCRIPTION("PXA27x/PXA3xx Realtime Clock Driver (RTC)");
490 MODULE_LICENSE("GPL");
491 MODULE_ALIAS("platform:pxa-rtc");