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>
29 #include <linux/slab.h>
31 #include <mach/hardware.h>
33 #define TIMER_FREQ CLOCK_TICK_RATE
34 #define RTC_DEF_DIVIDER (32768 - 1)
35 #define RTC_DEF_TRIM 0
36 #define MAXFREQ_PERIODIC 1000
39 * PXA Registers and bits definitions
41 #define RTSR_PICE (1 << 15) /* Periodic interrupt count enable */
42 #define RTSR_PIALE (1 << 14) /* Periodic interrupt Alarm enable */
43 #define RTSR_PIAL (1 << 13) /* Periodic interrupt detected */
44 #define RTSR_SWALE2 (1 << 11) /* RTC stopwatch alarm2 enable */
45 #define RTSR_SWAL2 (1 << 10) /* RTC stopwatch alarm2 detected */
46 #define RTSR_SWALE1 (1 << 9) /* RTC stopwatch alarm1 enable */
47 #define RTSR_SWAL1 (1 << 8) /* RTC stopwatch alarm1 detected */
48 #define RTSR_RDALE2 (1 << 7) /* RTC alarm2 enable */
49 #define RTSR_RDAL2 (1 << 6) /* RTC alarm2 detected */
50 #define RTSR_RDALE1 (1 << 5) /* RTC alarm1 enable */
51 #define RTSR_RDAL1 (1 << 4) /* RTC alarm1 detected */
52 #define RTSR_HZE (1 << 3) /* HZ interrupt enable */
53 #define RTSR_ALE (1 << 2) /* RTC alarm interrupt enable */
54 #define RTSR_HZ (1 << 1) /* HZ rising-edge detected */
55 #define RTSR_AL (1 << 0) /* RTC alarm detected */
56 #define RTSR_TRIG_MASK (RTSR_AL | RTSR_HZ | RTSR_RDAL1 | RTSR_RDAL2\
57 | RTSR_SWAL1 | RTSR_SWAL2)
59 #define RYxR_YEAR_MASK (0xfff << RYxR_YEAR_S)
60 #define RYxR_MONTH_S 5
61 #define RYxR_MONTH_MASK (0xf << RYxR_MONTH_S)
62 #define RYxR_DAY_MASK 0x1f
63 #define RDxR_HOUR_S 12
64 #define RDxR_HOUR_MASK (0x1f << RDxR_HOUR_S)
66 #define RDxR_MIN_MASK (0x3f << RDxR_MIN_S)
67 #define RDxR_SEC_MASK 0x3f
78 #define rtc_readl(pxa_rtc, reg) \
79 __raw_readl((pxa_rtc)->base + (reg))
80 #define rtc_writel(pxa_rtc, reg, value) \
81 __raw_writel((value), (pxa_rtc)->base + (reg))
84 struct resource
*ress
;
88 struct rtc_device
*rtc
;
89 spinlock_t lock
; /* Protects this structure */
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_alarm_irq_enable(struct device
*dev
, unsigned int enabled
)
214 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
216 spin_lock_irq(&pxa_rtc
->lock
);
219 rtsr_set_bits(pxa_rtc
, RTSR_RDALE1
);
221 rtsr_clear_bits(pxa_rtc
, RTSR_RDALE1
);
223 spin_unlock_irq(&pxa_rtc
->lock
);
227 static int pxa_rtc_read_time(struct device
*dev
, struct rtc_time
*tm
)
229 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
232 rycr
= rtc_readl(pxa_rtc
, RYCR
);
233 rdcr
= rtc_readl(pxa_rtc
, RDCR
);
235 tm_calc(rycr
, rdcr
, tm
);
239 static int pxa_rtc_set_time(struct device
*dev
, struct rtc_time
*tm
)
241 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
243 rtc_writel(pxa_rtc
, RYCR
, ryxr_calc(tm
));
244 rtc_writel(pxa_rtc
, RDCR
, rdxr_calc(tm
));
249 static int pxa_rtc_read_alarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
251 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
252 u32 rtsr
, ryar
, rdar
;
254 ryar
= rtc_readl(pxa_rtc
, RYAR1
);
255 rdar
= rtc_readl(pxa_rtc
, RDAR1
);
256 tm_calc(ryar
, rdar
, &alrm
->time
);
258 rtsr
= rtc_readl(pxa_rtc
, RTSR
);
259 alrm
->enabled
= (rtsr
& RTSR_RDALE1
) ? 1 : 0;
260 alrm
->pending
= (rtsr
& RTSR_RDAL1
) ? 1 : 0;
264 static int pxa_rtc_set_alarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
266 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
269 spin_lock_irq(&pxa_rtc
->lock
);
271 rtc_writel(pxa_rtc
, RYAR1
, ryxr_calc(&alrm
->time
));
272 rtc_writel(pxa_rtc
, RDAR1
, rdxr_calc(&alrm
->time
));
274 rtsr
= rtc_readl(pxa_rtc
, RTSR
);
278 rtsr
&= ~RTSR_RDALE1
;
279 rtc_writel(pxa_rtc
, RTSR
, rtsr
);
281 spin_unlock_irq(&pxa_rtc
->lock
);
286 static int pxa_rtc_proc(struct device
*dev
, struct seq_file
*seq
)
288 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
290 seq_printf(seq
, "trim/divider\t: 0x%08x\n", rtc_readl(pxa_rtc
, RTTR
));
291 seq_printf(seq
, "update_IRQ\t: %s\n",
292 (rtc_readl(pxa_rtc
, RTSR
) & RTSR_HZE
) ? "yes" : "no");
293 seq_printf(seq
, "periodic_IRQ\t: %s\n",
294 (rtc_readl(pxa_rtc
, RTSR
) & RTSR_PIALE
) ? "yes" : "no");
295 seq_printf(seq
, "periodic_freq\t: %u\n", rtc_readl(pxa_rtc
, PIAR
));
300 static const struct rtc_class_ops pxa_rtc_ops
= {
301 .open
= pxa_rtc_open
,
302 .release
= pxa_rtc_release
,
303 .read_time
= pxa_rtc_read_time
,
304 .set_time
= pxa_rtc_set_time
,
305 .read_alarm
= pxa_rtc_read_alarm
,
306 .set_alarm
= pxa_rtc_set_alarm
,
307 .alarm_irq_enable
= pxa_alarm_irq_enable
,
308 .proc
= pxa_rtc_proc
,
311 static int __init
pxa_rtc_probe(struct platform_device
*pdev
)
313 struct device
*dev
= &pdev
->dev
;
314 struct pxa_rtc
*pxa_rtc
;
318 pxa_rtc
= kzalloc(sizeof(struct pxa_rtc
), GFP_KERNEL
);
322 spin_lock_init(&pxa_rtc
->lock
);
323 platform_set_drvdata(pdev
, pxa_rtc
);
326 pxa_rtc
->ress
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
327 if (!pxa_rtc
->ress
) {
328 dev_err(dev
, "No I/O memory resource defined\n");
332 pxa_rtc
->irq_1Hz
= platform_get_irq(pdev
, 0);
333 if (pxa_rtc
->irq_1Hz
< 0) {
334 dev_err(dev
, "No 1Hz IRQ resource defined\n");
337 pxa_rtc
->irq_Alrm
= platform_get_irq(pdev
, 1);
338 if (pxa_rtc
->irq_Alrm
< 0) {
339 dev_err(dev
, "No alarm IRQ resource defined\n");
344 pxa_rtc
->base
= ioremap(pxa_rtc
->ress
->start
,
345 resource_size(pxa_rtc
->ress
));
346 if (!pxa_rtc
->base
) {
347 dev_err(&pdev
->dev
, "Unable to map pxa RTC I/O memory\n");
352 * If the clock divider is uninitialized then reset it to the
353 * default value to get the 1Hz clock.
355 if (rtc_readl(pxa_rtc
, RTTR
) == 0) {
356 rttr
= RTC_DEF_DIVIDER
+ (RTC_DEF_TRIM
<< 16);
357 rtc_writel(pxa_rtc
, RTTR
, rttr
);
358 dev_warn(dev
, "warning: initializing default clock"
359 " divider/trim value\n");
362 rtsr_clear_bits(pxa_rtc
, RTSR_PIALE
| RTSR_RDALE1
| RTSR_HZE
);
364 pxa_rtc
->rtc
= rtc_device_register("pxa-rtc", &pdev
->dev
, &pxa_rtc_ops
,
366 ret
= PTR_ERR(pxa_rtc
->rtc
);
367 if (IS_ERR(pxa_rtc
->rtc
)) {
368 dev_err(dev
, "Failed to register RTC device -> %d\n", ret
);
372 device_init_wakeup(dev
, 1);
377 iounmap(pxa_rtc
->base
);
384 static int __exit
pxa_rtc_remove(struct platform_device
*pdev
)
386 struct pxa_rtc
*pxa_rtc
= platform_get_drvdata(pdev
);
388 rtc_device_unregister(pxa_rtc
->rtc
);
390 spin_lock_irq(&pxa_rtc
->lock
);
391 iounmap(pxa_rtc
->base
);
392 spin_unlock_irq(&pxa_rtc
->lock
);
400 static int pxa_rtc_suspend(struct device
*dev
)
402 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
404 if (device_may_wakeup(dev
))
405 enable_irq_wake(pxa_rtc
->irq_Alrm
);
409 static int pxa_rtc_resume(struct device
*dev
)
411 struct pxa_rtc
*pxa_rtc
= dev_get_drvdata(dev
);
413 if (device_may_wakeup(dev
))
414 disable_irq_wake(pxa_rtc
->irq_Alrm
);
418 static const struct dev_pm_ops pxa_rtc_pm_ops
= {
419 .suspend
= pxa_rtc_suspend
,
420 .resume
= pxa_rtc_resume
,
424 static struct platform_driver pxa_rtc_driver
= {
425 .remove
= __exit_p(pxa_rtc_remove
),
429 .pm
= &pxa_rtc_pm_ops
,
434 static int __init
pxa_rtc_init(void)
436 if (cpu_is_pxa27x() || cpu_is_pxa3xx())
437 return platform_driver_probe(&pxa_rtc_driver
, pxa_rtc_probe
);
442 static void __exit
pxa_rtc_exit(void)
444 platform_driver_unregister(&pxa_rtc_driver
);
447 module_init(pxa_rtc_init
);
448 module_exit(pxa_rtc_exit
);
450 MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
451 MODULE_DESCRIPTION("PXA27x/PXA3xx Realtime Clock Driver (RTC)");
452 MODULE_LICENSE("GPL");
453 MODULE_ALIAS("platform:pxa-rtc");