Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6.git] / drivers / rtc / rtc-mxc.c
blob9a3895bc4f4da1dc86d6b5fad6668f6df85bb04d
1 /*
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
12 #include <linux/io.h>
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 #define RTC_INPUT_CLK_32768HZ (0x00 << 5)
21 #define RTC_INPUT_CLK_32000HZ (0x01 << 5)
22 #define RTC_INPUT_CLK_38400HZ (0x02 << 5)
24 #define RTC_SW_BIT (1 << 0)
25 #define RTC_ALM_BIT (1 << 2)
26 #define RTC_1HZ_BIT (1 << 4)
27 #define RTC_2HZ_BIT (1 << 7)
28 #define RTC_SAM0_BIT (1 << 8)
29 #define RTC_SAM1_BIT (1 << 9)
30 #define RTC_SAM2_BIT (1 << 10)
31 #define RTC_SAM3_BIT (1 << 11)
32 #define RTC_SAM4_BIT (1 << 12)
33 #define RTC_SAM5_BIT (1 << 13)
34 #define RTC_SAM6_BIT (1 << 14)
35 #define RTC_SAM7_BIT (1 << 15)
36 #define PIT_ALL_ON (RTC_2HZ_BIT | RTC_SAM0_BIT | RTC_SAM1_BIT | \
37 RTC_SAM2_BIT | RTC_SAM3_BIT | RTC_SAM4_BIT | \
38 RTC_SAM5_BIT | RTC_SAM6_BIT | RTC_SAM7_BIT)
40 #define RTC_ENABLE_BIT (1 << 7)
42 #define MAX_PIE_NUM 9
43 #define MAX_PIE_FREQ 512
44 static const u32 PIE_BIT_DEF[MAX_PIE_NUM][2] = {
45 { 2, RTC_2HZ_BIT },
46 { 4, RTC_SAM0_BIT },
47 { 8, RTC_SAM1_BIT },
48 { 16, RTC_SAM2_BIT },
49 { 32, RTC_SAM3_BIT },
50 { 64, RTC_SAM4_BIT },
51 { 128, RTC_SAM5_BIT },
52 { 256, RTC_SAM6_BIT },
53 { MAX_PIE_FREQ, RTC_SAM7_BIT },
56 #define MXC_RTC_TIME 0
57 #define MXC_RTC_ALARM 1
59 #define RTC_HOURMIN 0x00 /* 32bit rtc hour/min counter reg */
60 #define RTC_SECOND 0x04 /* 32bit rtc seconds counter reg */
61 #define RTC_ALRM_HM 0x08 /* 32bit rtc alarm hour/min reg */
62 #define RTC_ALRM_SEC 0x0C /* 32bit rtc alarm seconds reg */
63 #define RTC_RTCCTL 0x10 /* 32bit rtc control reg */
64 #define RTC_RTCISR 0x14 /* 32bit rtc interrupt status reg */
65 #define RTC_RTCIENR 0x18 /* 32bit rtc interrupt enable reg */
66 #define RTC_STPWCH 0x1C /* 32bit rtc stopwatch min reg */
67 #define RTC_DAYR 0x20 /* 32bit rtc days counter reg */
68 #define RTC_DAYALARM 0x24 /* 32bit rtc day alarm reg */
69 #define RTC_TEST1 0x28 /* 32bit rtc test reg 1 */
70 #define RTC_TEST2 0x2C /* 32bit rtc test reg 2 */
71 #define RTC_TEST3 0x30 /* 32bit rtc test reg 3 */
73 enum imx_rtc_type {
74 IMX1_RTC,
75 IMX21_RTC,
78 struct rtc_plat_data {
79 struct rtc_device *rtc;
80 void __iomem *ioaddr;
81 int irq;
82 struct clk *clk;
83 struct rtc_time g_rtc_alarm;
84 enum imx_rtc_type devtype;
87 static struct platform_device_id imx_rtc_devtype[] = {
89 .name = "imx1-rtc",
90 .driver_data = IMX1_RTC,
91 }, {
92 .name = "imx21-rtc",
93 .driver_data = IMX21_RTC,
94 }, {
95 /* sentinel */
98 MODULE_DEVICE_TABLE(platform, imx_rtc_devtype);
100 static inline int is_imx1_rtc(struct rtc_plat_data *data)
102 return data->devtype == IMX1_RTC;
106 * This function is used to obtain the RTC time or the alarm value in
107 * second.
109 static u32 get_alarm_or_time(struct device *dev, int time_alarm)
111 struct platform_device *pdev = to_platform_device(dev);
112 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
113 void __iomem *ioaddr = pdata->ioaddr;
114 u32 day = 0, hr = 0, min = 0, sec = 0, hr_min = 0;
116 switch (time_alarm) {
117 case MXC_RTC_TIME:
118 day = readw(ioaddr + RTC_DAYR);
119 hr_min = readw(ioaddr + RTC_HOURMIN);
120 sec = readw(ioaddr + RTC_SECOND);
121 break;
122 case MXC_RTC_ALARM:
123 day = readw(ioaddr + RTC_DAYALARM);
124 hr_min = readw(ioaddr + RTC_ALRM_HM) & 0xffff;
125 sec = readw(ioaddr + RTC_ALRM_SEC);
126 break;
129 hr = hr_min >> 8;
130 min = hr_min & 0xff;
132 return (((day * 24 + hr) * 60) + min) * 60 + sec;
136 * This function sets the RTC alarm value or the time value.
138 static void set_alarm_or_time(struct device *dev, int time_alarm, u32 time)
140 u32 day, hr, min, sec, temp;
141 struct platform_device *pdev = to_platform_device(dev);
142 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
143 void __iomem *ioaddr = pdata->ioaddr;
145 day = time / 86400;
146 time -= day * 86400;
148 /* time is within a day now */
149 hr = time / 3600;
150 time -= hr * 3600;
152 /* time is within an hour now */
153 min = time / 60;
154 sec = time - min * 60;
156 temp = (hr << 8) + min;
158 switch (time_alarm) {
159 case MXC_RTC_TIME:
160 writew(day, ioaddr + RTC_DAYR);
161 writew(sec, ioaddr + RTC_SECOND);
162 writew(temp, ioaddr + RTC_HOURMIN);
163 break;
164 case MXC_RTC_ALARM:
165 writew(day, ioaddr + RTC_DAYALARM);
166 writew(sec, ioaddr + RTC_ALRM_SEC);
167 writew(temp, ioaddr + RTC_ALRM_HM);
168 break;
173 * This function updates the RTC alarm registers and then clears all the
174 * interrupt status bits.
176 static int rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
178 struct rtc_time alarm_tm, now_tm;
179 unsigned long now, time;
180 struct platform_device *pdev = to_platform_device(dev);
181 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
182 void __iomem *ioaddr = pdata->ioaddr;
184 now = get_alarm_or_time(dev, MXC_RTC_TIME);
185 rtc_time_to_tm(now, &now_tm);
186 alarm_tm.tm_year = now_tm.tm_year;
187 alarm_tm.tm_mon = now_tm.tm_mon;
188 alarm_tm.tm_mday = now_tm.tm_mday;
189 alarm_tm.tm_hour = alrm->tm_hour;
190 alarm_tm.tm_min = alrm->tm_min;
191 alarm_tm.tm_sec = alrm->tm_sec;
192 rtc_tm_to_time(&alarm_tm, &time);
194 /* clear all the interrupt status bits */
195 writew(readw(ioaddr + RTC_RTCISR), ioaddr + RTC_RTCISR);
196 set_alarm_or_time(dev, MXC_RTC_ALARM, time);
198 return 0;
201 static void mxc_rtc_irq_enable(struct device *dev, unsigned int bit,
202 unsigned int enabled)
204 struct platform_device *pdev = to_platform_device(dev);
205 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
206 void __iomem *ioaddr = pdata->ioaddr;
207 u32 reg;
209 spin_lock_irq(&pdata->rtc->irq_lock);
210 reg = readw(ioaddr + RTC_RTCIENR);
212 if (enabled)
213 reg |= bit;
214 else
215 reg &= ~bit;
217 writew(reg, ioaddr + RTC_RTCIENR);
218 spin_unlock_irq(&pdata->rtc->irq_lock);
221 /* This function is the RTC interrupt service routine. */
222 static irqreturn_t mxc_rtc_interrupt(int irq, void *dev_id)
224 struct platform_device *pdev = dev_id;
225 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
226 void __iomem *ioaddr = pdata->ioaddr;
227 unsigned long flags;
228 u32 status;
229 u32 events = 0;
231 spin_lock_irqsave(&pdata->rtc->irq_lock, flags);
232 status = readw(ioaddr + RTC_RTCISR) & readw(ioaddr + RTC_RTCIENR);
233 /* clear interrupt sources */
234 writew(status, ioaddr + RTC_RTCISR);
236 /* update irq data & counter */
237 if (status & RTC_ALM_BIT) {
238 events |= (RTC_AF | RTC_IRQF);
239 /* RTC alarm should be one-shot */
240 mxc_rtc_irq_enable(&pdev->dev, RTC_ALM_BIT, 0);
243 if (status & RTC_1HZ_BIT)
244 events |= (RTC_UF | RTC_IRQF);
246 if (status & PIT_ALL_ON)
247 events |= (RTC_PF | RTC_IRQF);
249 rtc_update_irq(pdata->rtc, 1, events);
250 spin_unlock_irqrestore(&pdata->rtc->irq_lock, flags);
252 return IRQ_HANDLED;
256 * Clear all interrupts and release the IRQ
258 static void mxc_rtc_release(struct device *dev)
260 struct platform_device *pdev = to_platform_device(dev);
261 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
262 void __iomem *ioaddr = pdata->ioaddr;
264 spin_lock_irq(&pdata->rtc->irq_lock);
266 /* Disable all rtc interrupts */
267 writew(0, ioaddr + RTC_RTCIENR);
269 /* Clear all interrupt status */
270 writew(0xffffffff, ioaddr + RTC_RTCISR);
272 spin_unlock_irq(&pdata->rtc->irq_lock);
275 static int mxc_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
277 mxc_rtc_irq_enable(dev, RTC_ALM_BIT, enabled);
278 return 0;
282 * This function reads the current RTC time into tm in Gregorian date.
284 static int mxc_rtc_read_time(struct device *dev, struct rtc_time *tm)
286 u32 val;
288 /* Avoid roll-over from reading the different registers */
289 do {
290 val = get_alarm_or_time(dev, MXC_RTC_TIME);
291 } while (val != get_alarm_or_time(dev, MXC_RTC_TIME));
293 rtc_time_to_tm(val, tm);
295 return 0;
299 * This function sets the internal RTC time based on tm in Gregorian date.
301 static int mxc_rtc_set_mmss(struct device *dev, unsigned long time)
303 struct platform_device *pdev = to_platform_device(dev);
304 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
307 * TTC_DAYR register is 9-bit in MX1 SoC, save time and day of year only
309 if (is_imx1_rtc(pdata)) {
310 struct rtc_time tm;
312 rtc_time_to_tm(time, &tm);
313 tm.tm_year = 70;
314 rtc_tm_to_time(&tm, &time);
317 /* Avoid roll-over from reading the different registers */
318 do {
319 set_alarm_or_time(dev, MXC_RTC_TIME, time);
320 } while (time != get_alarm_or_time(dev, MXC_RTC_TIME));
322 return 0;
326 * This function reads the current alarm value into the passed in 'alrm'
327 * argument. It updates the alrm's pending field value based on the whether
328 * an alarm interrupt occurs or not.
330 static int mxc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
332 struct platform_device *pdev = to_platform_device(dev);
333 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
334 void __iomem *ioaddr = pdata->ioaddr;
336 rtc_time_to_tm(get_alarm_or_time(dev, MXC_RTC_ALARM), &alrm->time);
337 alrm->pending = ((readw(ioaddr + RTC_RTCISR) & RTC_ALM_BIT)) ? 1 : 0;
339 return 0;
343 * This function sets the RTC alarm based on passed in alrm.
345 static int mxc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
347 struct platform_device *pdev = to_platform_device(dev);
348 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
349 int ret;
351 ret = rtc_update_alarm(dev, &alrm->time);
352 if (ret)
353 return ret;
355 memcpy(&pdata->g_rtc_alarm, &alrm->time, sizeof(struct rtc_time));
356 mxc_rtc_irq_enable(dev, RTC_ALM_BIT, alrm->enabled);
358 return 0;
361 /* RTC layer */
362 static struct rtc_class_ops mxc_rtc_ops = {
363 .release = mxc_rtc_release,
364 .read_time = mxc_rtc_read_time,
365 .set_mmss = mxc_rtc_set_mmss,
366 .read_alarm = mxc_rtc_read_alarm,
367 .set_alarm = mxc_rtc_set_alarm,
368 .alarm_irq_enable = mxc_rtc_alarm_irq_enable,
371 static int mxc_rtc_probe(struct platform_device *pdev)
373 struct resource *res;
374 struct rtc_device *rtc;
375 struct rtc_plat_data *pdata = NULL;
376 u32 reg;
377 unsigned long rate;
378 int ret;
380 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
381 if (!res)
382 return -ENODEV;
384 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
385 if (!pdata)
386 return -ENOMEM;
388 pdata->devtype = pdev->id_entry->driver_data;
390 if (!devm_request_mem_region(&pdev->dev, res->start,
391 resource_size(res), pdev->name))
392 return -EBUSY;
394 pdata->ioaddr = devm_ioremap(&pdev->dev, res->start,
395 resource_size(res));
397 pdata->clk = devm_clk_get(&pdev->dev, NULL);
398 if (IS_ERR(pdata->clk)) {
399 dev_err(&pdev->dev, "unable to get clock!\n");
400 ret = PTR_ERR(pdata->clk);
401 goto exit_free_pdata;
404 clk_prepare_enable(pdata->clk);
405 rate = clk_get_rate(pdata->clk);
407 if (rate == 32768)
408 reg = RTC_INPUT_CLK_32768HZ;
409 else if (rate == 32000)
410 reg = RTC_INPUT_CLK_32000HZ;
411 else if (rate == 38400)
412 reg = RTC_INPUT_CLK_38400HZ;
413 else {
414 dev_err(&pdev->dev, "rtc clock is not valid (%lu)\n", rate);
415 ret = -EINVAL;
416 goto exit_put_clk;
419 reg |= RTC_ENABLE_BIT;
420 writew(reg, (pdata->ioaddr + RTC_RTCCTL));
421 if (((readw(pdata->ioaddr + RTC_RTCCTL)) & RTC_ENABLE_BIT) == 0) {
422 dev_err(&pdev->dev, "hardware module can't be enabled!\n");
423 ret = -EIO;
424 goto exit_put_clk;
427 platform_set_drvdata(pdev, pdata);
429 /* Configure and enable the RTC */
430 pdata->irq = platform_get_irq(pdev, 0);
432 if (pdata->irq >= 0 &&
433 devm_request_irq(&pdev->dev, pdata->irq, mxc_rtc_interrupt,
434 IRQF_SHARED, pdev->name, pdev) < 0) {
435 dev_warn(&pdev->dev, "interrupt not available.\n");
436 pdata->irq = -1;
439 if (pdata->irq >=0)
440 device_init_wakeup(&pdev->dev, 1);
442 rtc = devm_rtc_device_register(&pdev->dev, pdev->name, &mxc_rtc_ops,
443 THIS_MODULE);
444 if (IS_ERR(rtc)) {
445 ret = PTR_ERR(rtc);
446 goto exit_clr_drvdata;
449 pdata->rtc = rtc;
451 return 0;
453 exit_clr_drvdata:
454 platform_set_drvdata(pdev, NULL);
455 exit_put_clk:
456 clk_disable_unprepare(pdata->clk);
458 exit_free_pdata:
460 return ret;
463 static int mxc_rtc_remove(struct platform_device *pdev)
465 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
467 clk_disable_unprepare(pdata->clk);
468 platform_set_drvdata(pdev, NULL);
470 return 0;
473 #ifdef CONFIG_PM_SLEEP
474 static int mxc_rtc_suspend(struct device *dev)
476 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
478 if (device_may_wakeup(dev))
479 enable_irq_wake(pdata->irq);
481 return 0;
484 static int mxc_rtc_resume(struct device *dev)
486 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
488 if (device_may_wakeup(dev))
489 disable_irq_wake(pdata->irq);
491 return 0;
493 #endif
495 static SIMPLE_DEV_PM_OPS(mxc_rtc_pm_ops, mxc_rtc_suspend, mxc_rtc_resume);
497 static struct platform_driver mxc_rtc_driver = {
498 .driver = {
499 .name = "mxc_rtc",
500 .pm = &mxc_rtc_pm_ops,
501 .owner = THIS_MODULE,
503 .id_table = imx_rtc_devtype,
504 .probe = mxc_rtc_probe,
505 .remove = mxc_rtc_remove,
508 module_platform_driver(mxc_rtc_driver)
510 MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
511 MODULE_DESCRIPTION("RTC driver for Freescale MXC");
512 MODULE_LICENSE("GPL");