2 * Copyright 2004-2008 Freescale Semiconductor, Inc. All Rights Reserved.
4 * The code contained herein is licensed under the GNU General Public
5 * License. You may obtain a copy of the GNU General Public License
6 * Version 2 or later at the following locations:
8 * http://www.opensource.org/licenses/gpl-license.html
9 * http://www.gnu.org/copyleft/gpl.html
13 #include <linux/rtc.h>
14 #include <linux/module.h>
15 #include <linux/slab.h>
16 #include <linux/interrupt.h>
17 #include <linux/platform_device.h>
18 #include <linux/clk.h>
20 #include <mach/hardware.h>
22 #define RTC_INPUT_CLK_32768HZ (0x00 << 5)
23 #define RTC_INPUT_CLK_32000HZ (0x01 << 5)
24 #define RTC_INPUT_CLK_38400HZ (0x02 << 5)
26 #define RTC_SW_BIT (1 << 0)
27 #define RTC_ALM_BIT (1 << 2)
28 #define RTC_1HZ_BIT (1 << 4)
29 #define RTC_2HZ_BIT (1 << 7)
30 #define RTC_SAM0_BIT (1 << 8)
31 #define RTC_SAM1_BIT (1 << 9)
32 #define RTC_SAM2_BIT (1 << 10)
33 #define RTC_SAM3_BIT (1 << 11)
34 #define RTC_SAM4_BIT (1 << 12)
35 #define RTC_SAM5_BIT (1 << 13)
36 #define RTC_SAM6_BIT (1 << 14)
37 #define RTC_SAM7_BIT (1 << 15)
38 #define PIT_ALL_ON (RTC_2HZ_BIT | RTC_SAM0_BIT | RTC_SAM1_BIT | \
39 RTC_SAM2_BIT | RTC_SAM3_BIT | RTC_SAM4_BIT | \
40 RTC_SAM5_BIT | RTC_SAM6_BIT | RTC_SAM7_BIT)
42 #define RTC_ENABLE_BIT (1 << 7)
45 #define MAX_PIE_FREQ 512
46 static const u32 PIE_BIT_DEF
[MAX_PIE_NUM
][2] = {
53 { 128, RTC_SAM5_BIT
},
54 { 256, RTC_SAM6_BIT
},
55 { MAX_PIE_FREQ
, RTC_SAM7_BIT
},
58 #define MXC_RTC_TIME 0
59 #define MXC_RTC_ALARM 1
61 #define RTC_HOURMIN 0x00 /* 32bit rtc hour/min counter reg */
62 #define RTC_SECOND 0x04 /* 32bit rtc seconds counter reg */
63 #define RTC_ALRM_HM 0x08 /* 32bit rtc alarm hour/min reg */
64 #define RTC_ALRM_SEC 0x0C /* 32bit rtc alarm seconds reg */
65 #define RTC_RTCCTL 0x10 /* 32bit rtc control reg */
66 #define RTC_RTCISR 0x14 /* 32bit rtc interrupt status reg */
67 #define RTC_RTCIENR 0x18 /* 32bit rtc interrupt enable reg */
68 #define RTC_STPWCH 0x1C /* 32bit rtc stopwatch min reg */
69 #define RTC_DAYR 0x20 /* 32bit rtc days counter reg */
70 #define RTC_DAYALARM 0x24 /* 32bit rtc day alarm reg */
71 #define RTC_TEST1 0x28 /* 32bit rtc test reg 1 */
72 #define RTC_TEST2 0x2C /* 32bit rtc test reg 2 */
73 #define RTC_TEST3 0x30 /* 32bit rtc test reg 3 */
75 struct rtc_plat_data
{
76 struct rtc_device
*rtc
;
80 struct rtc_time g_rtc_alarm
;
84 * This function is used to obtain the RTC time or the alarm value in
87 static u32
get_alarm_or_time(struct device
*dev
, int time_alarm
)
89 struct platform_device
*pdev
= to_platform_device(dev
);
90 struct rtc_plat_data
*pdata
= platform_get_drvdata(pdev
);
91 void __iomem
*ioaddr
= pdata
->ioaddr
;
92 u32 day
= 0, hr
= 0, min
= 0, sec
= 0, hr_min
= 0;
96 day
= readw(ioaddr
+ RTC_DAYR
);
97 hr_min
= readw(ioaddr
+ RTC_HOURMIN
);
98 sec
= readw(ioaddr
+ RTC_SECOND
);
101 day
= readw(ioaddr
+ RTC_DAYALARM
);
102 hr_min
= readw(ioaddr
+ RTC_ALRM_HM
) & 0xffff;
103 sec
= readw(ioaddr
+ RTC_ALRM_SEC
);
110 return (((day
* 24 + hr
) * 60) + min
) * 60 + sec
;
114 * This function sets the RTC alarm value or the time value.
116 static void set_alarm_or_time(struct device
*dev
, int time_alarm
, u32 time
)
118 u32 day
, hr
, min
, sec
, temp
;
119 struct platform_device
*pdev
= to_platform_device(dev
);
120 struct rtc_plat_data
*pdata
= platform_get_drvdata(pdev
);
121 void __iomem
*ioaddr
= pdata
->ioaddr
;
126 /* time is within a day now */
130 /* time is within an hour now */
132 sec
= time
- min
* 60;
134 temp
= (hr
<< 8) + min
;
136 switch (time_alarm
) {
138 writew(day
, ioaddr
+ RTC_DAYR
);
139 writew(sec
, ioaddr
+ RTC_SECOND
);
140 writew(temp
, ioaddr
+ RTC_HOURMIN
);
143 writew(day
, ioaddr
+ RTC_DAYALARM
);
144 writew(sec
, ioaddr
+ RTC_ALRM_SEC
);
145 writew(temp
, ioaddr
+ RTC_ALRM_HM
);
151 * This function updates the RTC alarm registers and then clears all the
152 * interrupt status bits.
154 static int rtc_update_alarm(struct device
*dev
, struct rtc_time
*alrm
)
156 struct rtc_time alarm_tm
, now_tm
;
157 unsigned long now
, time
;
158 struct platform_device
*pdev
= to_platform_device(dev
);
159 struct rtc_plat_data
*pdata
= platform_get_drvdata(pdev
);
160 void __iomem
*ioaddr
= pdata
->ioaddr
;
162 now
= get_alarm_or_time(dev
, MXC_RTC_TIME
);
163 rtc_time_to_tm(now
, &now_tm
);
164 alarm_tm
.tm_year
= now_tm
.tm_year
;
165 alarm_tm
.tm_mon
= now_tm
.tm_mon
;
166 alarm_tm
.tm_mday
= now_tm
.tm_mday
;
167 alarm_tm
.tm_hour
= alrm
->tm_hour
;
168 alarm_tm
.tm_min
= alrm
->tm_min
;
169 alarm_tm
.tm_sec
= alrm
->tm_sec
;
170 rtc_tm_to_time(&alarm_tm
, &time
);
172 /* clear all the interrupt status bits */
173 writew(readw(ioaddr
+ RTC_RTCISR
), ioaddr
+ RTC_RTCISR
);
174 set_alarm_or_time(dev
, MXC_RTC_ALARM
, time
);
179 static void mxc_rtc_irq_enable(struct device
*dev
, unsigned int bit
,
180 unsigned int enabled
)
182 struct platform_device
*pdev
= to_platform_device(dev
);
183 struct rtc_plat_data
*pdata
= platform_get_drvdata(pdev
);
184 void __iomem
*ioaddr
= pdata
->ioaddr
;
187 spin_lock_irq(&pdata
->rtc
->irq_lock
);
188 reg
= readw(ioaddr
+ RTC_RTCIENR
);
195 writew(reg
, ioaddr
+ RTC_RTCIENR
);
196 spin_unlock_irq(&pdata
->rtc
->irq_lock
);
199 /* This function is the RTC interrupt service routine. */
200 static irqreturn_t
mxc_rtc_interrupt(int irq
, void *dev_id
)
202 struct platform_device
*pdev
= dev_id
;
203 struct rtc_plat_data
*pdata
= platform_get_drvdata(pdev
);
204 void __iomem
*ioaddr
= pdata
->ioaddr
;
208 spin_lock_irq(&pdata
->rtc
->irq_lock
);
209 status
= readw(ioaddr
+ RTC_RTCISR
) & readw(ioaddr
+ RTC_RTCIENR
);
210 /* clear interrupt sources */
211 writew(status
, ioaddr
+ RTC_RTCISR
);
213 /* update irq data & counter */
214 if (status
& RTC_ALM_BIT
) {
215 events
|= (RTC_AF
| RTC_IRQF
);
216 /* RTC alarm should be one-shot */
217 mxc_rtc_irq_enable(&pdev
->dev
, RTC_ALM_BIT
, 0);
220 if (status
& RTC_1HZ_BIT
)
221 events
|= (RTC_UF
| RTC_IRQF
);
223 if (status
& PIT_ALL_ON
)
224 events
|= (RTC_PF
| RTC_IRQF
);
226 rtc_update_irq(pdata
->rtc
, 1, events
);
227 spin_unlock_irq(&pdata
->rtc
->irq_lock
);
233 * Clear all interrupts and release the IRQ
235 static void mxc_rtc_release(struct device
*dev
)
237 struct platform_device
*pdev
= to_platform_device(dev
);
238 struct rtc_plat_data
*pdata
= platform_get_drvdata(pdev
);
239 void __iomem
*ioaddr
= pdata
->ioaddr
;
241 spin_lock_irq(&pdata
->rtc
->irq_lock
);
243 /* Disable all rtc interrupts */
244 writew(0, ioaddr
+ RTC_RTCIENR
);
246 /* Clear all interrupt status */
247 writew(0xffffffff, ioaddr
+ RTC_RTCISR
);
249 spin_unlock_irq(&pdata
->rtc
->irq_lock
);
252 static int mxc_rtc_alarm_irq_enable(struct device
*dev
, unsigned int enabled
)
254 mxc_rtc_irq_enable(dev
, RTC_ALM_BIT
, enabled
);
259 * This function reads the current RTC time into tm in Gregorian date.
261 static int mxc_rtc_read_time(struct device
*dev
, struct rtc_time
*tm
)
265 /* Avoid roll-over from reading the different registers */
267 val
= get_alarm_or_time(dev
, MXC_RTC_TIME
);
268 } while (val
!= get_alarm_or_time(dev
, MXC_RTC_TIME
));
270 rtc_time_to_tm(val
, tm
);
276 * This function sets the internal RTC time based on tm in Gregorian date.
278 static int mxc_rtc_set_mmss(struct device
*dev
, unsigned long time
)
281 * TTC_DAYR register is 9-bit in MX1 SoC, save time and day of year only
286 rtc_time_to_tm(time
, &tm
);
288 rtc_tm_to_time(&tm
, &time
);
291 /* Avoid roll-over from reading the different registers */
293 set_alarm_or_time(dev
, MXC_RTC_TIME
, time
);
294 } while (time
!= get_alarm_or_time(dev
, MXC_RTC_TIME
));
300 * This function reads the current alarm value into the passed in 'alrm'
301 * argument. It updates the alrm's pending field value based on the whether
302 * an alarm interrupt occurs or not.
304 static int mxc_rtc_read_alarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
306 struct platform_device
*pdev
= to_platform_device(dev
);
307 struct rtc_plat_data
*pdata
= platform_get_drvdata(pdev
);
308 void __iomem
*ioaddr
= pdata
->ioaddr
;
310 rtc_time_to_tm(get_alarm_or_time(dev
, MXC_RTC_ALARM
), &alrm
->time
);
311 alrm
->pending
= ((readw(ioaddr
+ RTC_RTCISR
) & RTC_ALM_BIT
)) ? 1 : 0;
317 * This function sets the RTC alarm based on passed in alrm.
319 static int mxc_rtc_set_alarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
321 struct platform_device
*pdev
= to_platform_device(dev
);
322 struct rtc_plat_data
*pdata
= platform_get_drvdata(pdev
);
325 ret
= rtc_update_alarm(dev
, &alrm
->time
);
329 memcpy(&pdata
->g_rtc_alarm
, &alrm
->time
, sizeof(struct rtc_time
));
330 mxc_rtc_irq_enable(dev
, RTC_ALM_BIT
, alrm
->enabled
);
336 static struct rtc_class_ops mxc_rtc_ops
= {
337 .release
= mxc_rtc_release
,
338 .read_time
= mxc_rtc_read_time
,
339 .set_mmss
= mxc_rtc_set_mmss
,
340 .read_alarm
= mxc_rtc_read_alarm
,
341 .set_alarm
= mxc_rtc_set_alarm
,
342 .alarm_irq_enable
= mxc_rtc_alarm_irq_enable
,
345 static int __init
mxc_rtc_probe(struct platform_device
*pdev
)
347 struct resource
*res
;
348 struct rtc_device
*rtc
;
349 struct rtc_plat_data
*pdata
= NULL
;
354 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
358 pdata
= devm_kzalloc(&pdev
->dev
, sizeof(*pdata
), GFP_KERNEL
);
362 if (!devm_request_mem_region(&pdev
->dev
, res
->start
,
363 resource_size(res
), pdev
->name
))
366 pdata
->ioaddr
= devm_ioremap(&pdev
->dev
, res
->start
,
369 pdata
->clk
= clk_get(&pdev
->dev
, "rtc");
370 if (IS_ERR(pdata
->clk
)) {
371 dev_err(&pdev
->dev
, "unable to get clock!\n");
372 ret
= PTR_ERR(pdata
->clk
);
373 goto exit_free_pdata
;
376 clk_enable(pdata
->clk
);
377 rate
= clk_get_rate(pdata
->clk
);
380 reg
= RTC_INPUT_CLK_32768HZ
;
381 else if (rate
== 32000)
382 reg
= RTC_INPUT_CLK_32000HZ
;
383 else if (rate
== 38400)
384 reg
= RTC_INPUT_CLK_38400HZ
;
386 dev_err(&pdev
->dev
, "rtc clock is not valid (%lu)\n", rate
);
391 reg
|= RTC_ENABLE_BIT
;
392 writew(reg
, (pdata
->ioaddr
+ RTC_RTCCTL
));
393 if (((readw(pdata
->ioaddr
+ RTC_RTCCTL
)) & RTC_ENABLE_BIT
) == 0) {
394 dev_err(&pdev
->dev
, "hardware module can't be enabled!\n");
399 platform_set_drvdata(pdev
, pdata
);
401 /* Configure and enable the RTC */
402 pdata
->irq
= platform_get_irq(pdev
, 0);
404 if (pdata
->irq
>= 0 &&
405 devm_request_irq(&pdev
->dev
, pdata
->irq
, mxc_rtc_interrupt
,
406 IRQF_SHARED
, pdev
->name
, pdev
) < 0) {
407 dev_warn(&pdev
->dev
, "interrupt not available.\n");
412 device_init_wakeup(&pdev
->dev
, 1);
414 rtc
= rtc_device_register(pdev
->name
, &pdev
->dev
, &mxc_rtc_ops
,
418 goto exit_clr_drvdata
;
426 platform_set_drvdata(pdev
, NULL
);
428 clk_disable(pdata
->clk
);
436 static int __exit
mxc_rtc_remove(struct platform_device
*pdev
)
438 struct rtc_plat_data
*pdata
= platform_get_drvdata(pdev
);
440 rtc_device_unregister(pdata
->rtc
);
442 clk_disable(pdata
->clk
);
444 platform_set_drvdata(pdev
, NULL
);
450 static int mxc_rtc_suspend(struct device
*dev
)
452 struct rtc_plat_data
*pdata
= dev_get_drvdata(dev
);
454 if (device_may_wakeup(dev
))
455 enable_irq_wake(pdata
->irq
);
460 static int mxc_rtc_resume(struct device
*dev
)
462 struct rtc_plat_data
*pdata
= dev_get_drvdata(dev
);
464 if (device_may_wakeup(dev
))
465 disable_irq_wake(pdata
->irq
);
470 static struct dev_pm_ops mxc_rtc_pm_ops
= {
471 .suspend
= mxc_rtc_suspend
,
472 .resume
= mxc_rtc_resume
,
476 static struct platform_driver mxc_rtc_driver
= {
480 .pm
= &mxc_rtc_pm_ops
,
482 .owner
= THIS_MODULE
,
484 .remove
= __exit_p(mxc_rtc_remove
),
487 static int __init
mxc_rtc_init(void)
489 return platform_driver_probe(&mxc_rtc_driver
, mxc_rtc_probe
);
492 static void __exit
mxc_rtc_exit(void)
494 platform_driver_unregister(&mxc_rtc_driver
);
497 module_init(mxc_rtc_init
);
498 module_exit(mxc_rtc_exit
);
500 MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
501 MODULE_DESCRIPTION("RTC driver for Freescale MXC");
502 MODULE_LICENSE("GPL");