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1/*
2 * drivers/rtc/rtc-spear.c
3 *
4 * Copyright (C) 2010 ST Microelectronics
5 * Rajeev Kumar<rajeev-dlh.kumar@st.com>
6 *
7 * This file is licensed under the terms of the GNU General Public
8 * License version 2. This program is licensed "as is" without any
9 * warranty of any kind, whether express or implied.
10 */
11
12#include <linux/bcd.h>
13#include <linux/clk.h>
14#include <linux/delay.h>
15#include <linux/init.h>
16#include <linux/io.h>
17#include <linux/irq.h>
18#include <linux/module.h>
19#include <linux/of.h>
20#include <linux/platform_device.h>
21#include <linux/rtc.h>
22#include <linux/slab.h>
23#include <linux/spinlock.h>
24
25/* RTC registers */
26#define TIME_REG 0x00
27#define DATE_REG 0x04
28#define ALARM_TIME_REG 0x08
29#define ALARM_DATE_REG 0x0C
30#define CTRL_REG 0x10
31#define STATUS_REG 0x14
32
33/* TIME_REG & ALARM_TIME_REG */
34#define SECONDS_UNITS (0xf<<0) /* seconds units position */
35#define SECONDS_TENS (0x7<<4) /* seconds tens position */
36#define MINUTES_UNITS (0xf<<8) /* minutes units position */
37#define MINUTES_TENS (0x7<<12) /* minutes tens position */
38#define HOURS_UNITS (0xf<<16) /* hours units position */
39#define HOURS_TENS (0x3<<20) /* hours tens position */
40
41/* DATE_REG & ALARM_DATE_REG */
42#define DAYS_UNITS (0xf<<0) /* days units position */
43#define DAYS_TENS (0x3<<4) /* days tens position */
44#define MONTHS_UNITS (0xf<<8) /* months units position */
45#define MONTHS_TENS (0x1<<12) /* months tens position */
46#define YEARS_UNITS (0xf<<16) /* years units position */
47#define YEARS_TENS (0xf<<20) /* years tens position */
48#define YEARS_HUNDREDS (0xf<<24) /* years hundereds position */
49#define YEARS_MILLENIUMS (0xf<<28) /* years millenium position */
50
51/* MASK SHIFT TIME_REG & ALARM_TIME_REG*/
52#define SECOND_SHIFT 0x00 /* seconds units */
53#define MINUTE_SHIFT 0x08 /* minutes units position */
54#define HOUR_SHIFT 0x10 /* hours units position */
55#define MDAY_SHIFT 0x00 /* Month day shift */
56#define MONTH_SHIFT 0x08 /* Month shift */
57#define YEAR_SHIFT 0x10 /* Year shift */
58
59#define SECOND_MASK 0x7F
60#define MIN_MASK 0x7F
61#define HOUR_MASK 0x3F
62#define DAY_MASK 0x3F
63#define MONTH_MASK 0x7F
64#define YEAR_MASK 0xFFFF
65
66/* date reg equal to time reg, for debug only */
67#define TIME_BYP (1<<9)
68#define INT_ENABLE (1<<31) /* interrupt enable */
69
70/* STATUS_REG */
71#define CLK_UNCONNECTED (1<<0)
72#define PEND_WR_TIME (1<<2)
73#define PEND_WR_DATE (1<<3)
74#define LOST_WR_TIME (1<<4)
75#define LOST_WR_DATE (1<<5)
76#define RTC_INT_MASK (1<<31)
77#define STATUS_BUSY (PEND_WR_TIME | PEND_WR_DATE)
78#define STATUS_FAIL (LOST_WR_TIME | LOST_WR_DATE)
79
80struct spear_rtc_config {
81 struct rtc_device *rtc;
82 struct clk *clk;
83 spinlock_t lock;
84 void __iomem *ioaddr;
85 unsigned int irq_wake;
86};
87
88static inline void spear_rtc_clear_interrupt(struct spear_rtc_config *config)
89{
90 unsigned int val;
91 unsigned long flags;
92
93 spin_lock_irqsave(&config->lock, flags);
94 val = readl(config->ioaddr + STATUS_REG);
95 val |= RTC_INT_MASK;
96 writel(val, config->ioaddr + STATUS_REG);
97 spin_unlock_irqrestore(&config->lock, flags);
98}
99
100static inline void spear_rtc_enable_interrupt(struct spear_rtc_config *config)
101{
102 unsigned int val;
103
104 val = readl(config->ioaddr + CTRL_REG);
105 if (!(val & INT_ENABLE)) {
106 spear_rtc_clear_interrupt(config);
107 val |= INT_ENABLE;
108 writel(val, config->ioaddr + CTRL_REG);
109 }
110}
111
112static inline void spear_rtc_disable_interrupt(struct spear_rtc_config *config)
113{
114 unsigned int val;
115
116 val = readl(config->ioaddr + CTRL_REG);
117 if (val & INT_ENABLE) {
118 val &= ~INT_ENABLE;
119 writel(val, config->ioaddr + CTRL_REG);
120 }
121}
122
123static inline int is_write_complete(struct spear_rtc_config *config)
124{
125 int ret = 0;
126 unsigned long flags;
127
128 spin_lock_irqsave(&config->lock, flags);
129 if ((readl(config->ioaddr + STATUS_REG)) & STATUS_FAIL)
130 ret = -EIO;
131 spin_unlock_irqrestore(&config->lock, flags);
132
133 return ret;
134}
135
136static void rtc_wait_not_busy(struct spear_rtc_config *config)
137{
138 int status, count = 0;
139 unsigned long flags;
140
141 /* Assuming BUSY may stay active for 80 msec) */
142 for (count = 0; count < 80; count++) {
143 spin_lock_irqsave(&config->lock, flags);
144 status = readl(config->ioaddr + STATUS_REG);
145 spin_unlock_irqrestore(&config->lock, flags);
146 if ((status & STATUS_BUSY) == 0)
147 break;
148 /* check status busy, after each msec */
149 msleep(1);
150 }
151}
152
153static irqreturn_t spear_rtc_irq(int irq, void *dev_id)
154{
155 struct spear_rtc_config *config = dev_id;
156 unsigned long flags, events = 0;
157 unsigned int irq_data;
158
159 spin_lock_irqsave(&config->lock, flags);
160 irq_data = readl(config->ioaddr + STATUS_REG);
161 spin_unlock_irqrestore(&config->lock, flags);
162
163 if ((irq_data & RTC_INT_MASK)) {
164 spear_rtc_clear_interrupt(config);
165 events = RTC_IRQF | RTC_AF;
166 rtc_update_irq(config->rtc, 1, events);
167 return IRQ_HANDLED;
168 } else
169 return IRQ_NONE;
170
171}
172
173static int tm2bcd(struct rtc_time *tm)
174{
175 if (rtc_valid_tm(tm) != 0)
176 return -EINVAL;
177 tm->tm_sec = bin2bcd(tm->tm_sec);
178 tm->tm_min = bin2bcd(tm->tm_min);
179 tm->tm_hour = bin2bcd(tm->tm_hour);
180 tm->tm_mday = bin2bcd(tm->tm_mday);
181 tm->tm_mon = bin2bcd(tm->tm_mon + 1);
182 tm->tm_year = bin2bcd(tm->tm_year);
183
184 return 0;
185}
186
187static void bcd2tm(struct rtc_time *tm)
188{
189 tm->tm_sec = bcd2bin(tm->tm_sec);
190 tm->tm_min = bcd2bin(tm->tm_min);
191 tm->tm_hour = bcd2bin(tm->tm_hour);
192 tm->tm_mday = bcd2bin(tm->tm_mday);
193 tm->tm_mon = bcd2bin(tm->tm_mon) - 1;
194 /* epoch == 1900 */
195 tm->tm_year = bcd2bin(tm->tm_year);
196}
197
198/*
199 * spear_rtc_read_time - set the time
200 * @dev: rtc device in use
201 * @tm: holds date and time
202 *
203 * This function read time and date. On success it will return 0
204 * otherwise -ve error is returned.
205 */
206static int spear_rtc_read_time(struct device *dev, struct rtc_time *tm)
207{
208 struct spear_rtc_config *config = dev_get_drvdata(dev);
209 unsigned int time, date;
210
211 /* we don't report wday/yday/isdst ... */
212 rtc_wait_not_busy(config);
213
214 time = readl(config->ioaddr + TIME_REG);
215 date = readl(config->ioaddr + DATE_REG);
216 tm->tm_sec = (time >> SECOND_SHIFT) & SECOND_MASK;
217 tm->tm_min = (time >> MINUTE_SHIFT) & MIN_MASK;
218 tm->tm_hour = (time >> HOUR_SHIFT) & HOUR_MASK;
219 tm->tm_mday = (date >> MDAY_SHIFT) & DAY_MASK;
220 tm->tm_mon = (date >> MONTH_SHIFT) & MONTH_MASK;
221 tm->tm_year = (date >> YEAR_SHIFT) & YEAR_MASK;
222
223 bcd2tm(tm);
224 return 0;
225}
226
227/*
228 * spear_rtc_set_time - set the time
229 * @dev: rtc device in use
230 * @tm: holds date and time
231 *
232 * This function set time and date. On success it will return 0
233 * otherwise -ve error is returned.
234 */
235static int spear_rtc_set_time(struct device *dev, struct rtc_time *tm)
236{
237 struct spear_rtc_config *config = dev_get_drvdata(dev);
238 unsigned int time, date, err = 0;
239
240 if (tm2bcd(tm) < 0)
241 return -EINVAL;
242
243 rtc_wait_not_busy(config);
244 time = (tm->tm_sec << SECOND_SHIFT) | (tm->tm_min << MINUTE_SHIFT) |
245 (tm->tm_hour << HOUR_SHIFT);
246 date = (tm->tm_mday << MDAY_SHIFT) | (tm->tm_mon << MONTH_SHIFT) |
247 (tm->tm_year << YEAR_SHIFT);
248 writel(time, config->ioaddr + TIME_REG);
249 writel(date, config->ioaddr + DATE_REG);
250 err = is_write_complete(config);
251 if (err < 0)
252 return err;
253
254 return 0;
255}
256
257/*
258 * spear_rtc_read_alarm - read the alarm time
259 * @dev: rtc device in use
260 * @alm: holds alarm date and time
261 *
262 * This function read alarm time and date. On success it will return 0
263 * otherwise -ve error is returned.
264 */
265static int spear_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
266{
267 struct spear_rtc_config *config = dev_get_drvdata(dev);
268 unsigned int time, date;
269
270 rtc_wait_not_busy(config);
271
272 time = readl(config->ioaddr + ALARM_TIME_REG);
273 date = readl(config->ioaddr + ALARM_DATE_REG);
274 alm->time.tm_sec = (time >> SECOND_SHIFT) & SECOND_MASK;
275 alm->time.tm_min = (time >> MINUTE_SHIFT) & MIN_MASK;
276 alm->time.tm_hour = (time >> HOUR_SHIFT) & HOUR_MASK;
277 alm->time.tm_mday = (date >> MDAY_SHIFT) & DAY_MASK;
278 alm->time.tm_mon = (date >> MONTH_SHIFT) & MONTH_MASK;
279 alm->time.tm_year = (date >> YEAR_SHIFT) & YEAR_MASK;
280
281 bcd2tm(&alm->time);
282 alm->enabled = readl(config->ioaddr + CTRL_REG) & INT_ENABLE;
283
284 return 0;
285}
286
287/*
288 * spear_rtc_set_alarm - set the alarm time
289 * @dev: rtc device in use
290 * @alm: holds alarm date and time
291 *
292 * This function set alarm time and date. On success it will return 0
293 * otherwise -ve error is returned.
294 */
295static int spear_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
296{
297 struct spear_rtc_config *config = dev_get_drvdata(dev);
298 unsigned int time, date, err = 0;
299
300 if (tm2bcd(&alm->time) < 0)
301 return -EINVAL;
302
303 rtc_wait_not_busy(config);
304
305 time = (alm->time.tm_sec << SECOND_SHIFT) | (alm->time.tm_min <<
306 MINUTE_SHIFT) | (alm->time.tm_hour << HOUR_SHIFT);
307 date = (alm->time.tm_mday << MDAY_SHIFT) | (alm->time.tm_mon <<
308 MONTH_SHIFT) | (alm->time.tm_year << YEAR_SHIFT);
309
310 writel(time, config->ioaddr + ALARM_TIME_REG);
311 writel(date, config->ioaddr + ALARM_DATE_REG);
312 err = is_write_complete(config);
313 if (err < 0)
314 return err;
315
316 if (alm->enabled)
317 spear_rtc_enable_interrupt(config);
318 else
319 spear_rtc_disable_interrupt(config);
320
321 return 0;
322}
323
324static int spear_alarm_irq_enable(struct device *dev, unsigned int enabled)
325{
326 struct spear_rtc_config *config = dev_get_drvdata(dev);
327 int ret = 0;
328
329 spear_rtc_clear_interrupt(config);
330
331 switch (enabled) {
332 case 0:
333 /* alarm off */
334 spear_rtc_disable_interrupt(config);
335 break;
336 case 1:
337 /* alarm on */
338 spear_rtc_enable_interrupt(config);
339 break;
340 default:
341 ret = -EINVAL;
342 break;
343 }
344
345 return ret;
346}
347
348static struct rtc_class_ops spear_rtc_ops = {
349 .read_time = spear_rtc_read_time,
350 .set_time = spear_rtc_set_time,
351 .read_alarm = spear_rtc_read_alarm,
352 .set_alarm = spear_rtc_set_alarm,
353 .alarm_irq_enable = spear_alarm_irq_enable,
354};
355
356static int __devinit spear_rtc_probe(struct platform_device *pdev)
357{
358 struct resource *res;
359 struct spear_rtc_config *config;
360 unsigned int status = 0;
361 int irq;
362
363 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
364 if (!res) {
365 dev_err(&pdev->dev, "no resource defined\n");
366 return -EBUSY;
367 }
368 if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
369 dev_err(&pdev->dev, "rtc region already claimed\n");
370 return -EBUSY;
371 }
372
373 config = kzalloc(sizeof(*config), GFP_KERNEL);
374 if (!config) {
375 dev_err(&pdev->dev, "out of memory\n");
376 status = -ENOMEM;
377 goto err_release_region;
378 }
379
380 config->clk = clk_get(&pdev->dev, NULL);
381 if (IS_ERR(config->clk)) {
382 status = PTR_ERR(config->clk);
383 goto err_kfree;
384 }
385
386 status = clk_enable(config->clk);
387 if (status < 0)
388 goto err_clk_put;
389
390 config->ioaddr = ioremap(res->start, resource_size(res));
391 if (!config->ioaddr) {
392 dev_err(&pdev->dev, "ioremap fail\n");
393 status = -ENOMEM;
394 goto err_disable_clock;
395 }
396
397 spin_lock_init(&config->lock);
398 platform_set_drvdata(pdev, config);
399
400 config->rtc = rtc_device_register(pdev->name, &pdev->dev,
401 &spear_rtc_ops, THIS_MODULE);
402 if (IS_ERR(config->rtc)) {
403 dev_err(&pdev->dev, "can't register RTC device, err %ld\n",
404 PTR_ERR(config->rtc));
405 status = PTR_ERR(config->rtc);
406 goto err_iounmap;
407 }
408
409 /* alarm irqs */
410 irq = platform_get_irq(pdev, 0);
411 if (irq < 0) {
412 dev_err(&pdev->dev, "no update irq?\n");
413 status = irq;
414 goto err_clear_platdata;
415 }
416
417 status = request_irq(irq, spear_rtc_irq, 0, pdev->name, config);
418 if (status) {
419 dev_err(&pdev->dev, "Alarm interrupt IRQ%d already \
420 claimed\n", irq);
421 goto err_clear_platdata;
422 }
423
424 if (!device_can_wakeup(&pdev->dev))
425 device_init_wakeup(&pdev->dev, 1);
426
427 return 0;
428
429err_clear_platdata:
430 platform_set_drvdata(pdev, NULL);
431 rtc_device_unregister(config->rtc);
432err_iounmap:
433 iounmap(config->ioaddr);
434err_disable_clock:
435 clk_disable(config->clk);
436err_clk_put:
437 clk_put(config->clk);
438err_kfree:
439 kfree(config);
440err_release_region:
441 release_mem_region(res->start, resource_size(res));
442
443 return status;
444}
445
446static int __devexit spear_rtc_remove(struct platform_device *pdev)
447{
448 struct spear_rtc_config *config = platform_get_drvdata(pdev);
449 int irq;
450 struct resource *res;
451
452 /* leave rtc running, but disable irqs */
453 spear_rtc_disable_interrupt(config);
454 device_init_wakeup(&pdev->dev, 0);
455 irq = platform_get_irq(pdev, 0);
456 if (irq)
457 free_irq(irq, pdev);
458 clk_disable(config->clk);
459 clk_put(config->clk);
460 iounmap(config->ioaddr);
461 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
462 if (res)
463 release_mem_region(res->start, resource_size(res));
464 platform_set_drvdata(pdev, NULL);
465 rtc_device_unregister(config->rtc);
466 kfree(config);
467
468 return 0;
469}
470
471#ifdef CONFIG_PM
472
473static int spear_rtc_suspend(struct platform_device *pdev, pm_message_t state)
474{
475 struct spear_rtc_config *config = platform_get_drvdata(pdev);
476 int irq;
477
478 irq = platform_get_irq(pdev, 0);
479 if (device_may_wakeup(&pdev->dev)) {
480 if (!enable_irq_wake(irq))
481 config->irq_wake = 1;
482 } else {
483 spear_rtc_disable_interrupt(config);
484 clk_disable(config->clk);
485 }
486
487 return 0;
488}
489
490static int spear_rtc_resume(struct platform_device *pdev)
491{
492 struct spear_rtc_config *config = platform_get_drvdata(pdev);
493 int irq;
494
495 irq = platform_get_irq(pdev, 0);
496
497 if (device_may_wakeup(&pdev->dev)) {
498 if (config->irq_wake) {
499 disable_irq_wake(irq);
500 config->irq_wake = 0;
501 }
502 } else {
503 clk_enable(config->clk);
504 spear_rtc_enable_interrupt(config);
505 }
506
507 return 0;
508}
509
510#else
511#define spear_rtc_suspend NULL
512#define spear_rtc_resume NULL
513#endif
514
515static void spear_rtc_shutdown(struct platform_device *pdev)
516{
517 struct spear_rtc_config *config = platform_get_drvdata(pdev);
518
519 spear_rtc_disable_interrupt(config);
520 clk_disable(config->clk);
521}
522
523#ifdef CONFIG_OF
524static const struct of_device_id spear_rtc_id_table[] = {
525 { .compatible = "st,spear600-rtc" },
526 {}
527};
528MODULE_DEVICE_TABLE(of, spear_rtc_id_table);
529#endif
530
531static struct platform_driver spear_rtc_driver = {
532 .probe = spear_rtc_probe,
533 .remove = __devexit_p(spear_rtc_remove),
534 .suspend = spear_rtc_suspend,
535 .resume = spear_rtc_resume,
536 .shutdown = spear_rtc_shutdown,
537 .driver = {
538 .name = "rtc-spear",
539 .of_match_table = of_match_ptr(spear_rtc_id_table),
540 },
541};
542
543module_platform_driver(spear_rtc_driver);
544
545MODULE_ALIAS("platform:rtc-spear");
546MODULE_AUTHOR("Rajeev Kumar <rajeev-dlh.kumar@st.com>");
547MODULE_DESCRIPTION("ST SPEAr Realtime Clock Driver (RTC)");
548MODULE_LICENSE("GPL");
1/*
2 * drivers/rtc/rtc-spear.c
3 *
4 * Copyright (C) 2010 ST Microelectronics
5 * Rajeev Kumar<rajeev-dlh.kumar@st.com>
6 *
7 * This file is licensed under the terms of the GNU General Public
8 * License version 2. This program is licensed "as is" without any
9 * warranty of any kind, whether express or implied.
10 */
11
12#include <linux/bcd.h>
13#include <linux/clk.h>
14#include <linux/delay.h>
15#include <linux/init.h>
16#include <linux/io.h>
17#include <linux/irq.h>
18#include <linux/module.h>
19#include <linux/of.h>
20#include <linux/platform_device.h>
21#include <linux/rtc.h>
22#include <linux/slab.h>
23#include <linux/spinlock.h>
24
25/* RTC registers */
26#define TIME_REG 0x00
27#define DATE_REG 0x04
28#define ALARM_TIME_REG 0x08
29#define ALARM_DATE_REG 0x0C
30#define CTRL_REG 0x10
31#define STATUS_REG 0x14
32
33/* TIME_REG & ALARM_TIME_REG */
34#define SECONDS_UNITS (0xf<<0) /* seconds units position */
35#define SECONDS_TENS (0x7<<4) /* seconds tens position */
36#define MINUTES_UNITS (0xf<<8) /* minutes units position */
37#define MINUTES_TENS (0x7<<12) /* minutes tens position */
38#define HOURS_UNITS (0xf<<16) /* hours units position */
39#define HOURS_TENS (0x3<<20) /* hours tens position */
40
41/* DATE_REG & ALARM_DATE_REG */
42#define DAYS_UNITS (0xf<<0) /* days units position */
43#define DAYS_TENS (0x3<<4) /* days tens position */
44#define MONTHS_UNITS (0xf<<8) /* months units position */
45#define MONTHS_TENS (0x1<<12) /* months tens position */
46#define YEARS_UNITS (0xf<<16) /* years units position */
47#define YEARS_TENS (0xf<<20) /* years tens position */
48#define YEARS_HUNDREDS (0xf<<24) /* years hundereds position */
49#define YEARS_MILLENIUMS (0xf<<28) /* years millenium position */
50
51/* MASK SHIFT TIME_REG & ALARM_TIME_REG*/
52#define SECOND_SHIFT 0x00 /* seconds units */
53#define MINUTE_SHIFT 0x08 /* minutes units position */
54#define HOUR_SHIFT 0x10 /* hours units position */
55#define MDAY_SHIFT 0x00 /* Month day shift */
56#define MONTH_SHIFT 0x08 /* Month shift */
57#define YEAR_SHIFT 0x10 /* Year shift */
58
59#define SECOND_MASK 0x7F
60#define MIN_MASK 0x7F
61#define HOUR_MASK 0x3F
62#define DAY_MASK 0x3F
63#define MONTH_MASK 0x7F
64#define YEAR_MASK 0xFFFF
65
66/* date reg equal to time reg, for debug only */
67#define TIME_BYP (1<<9)
68#define INT_ENABLE (1<<31) /* interrupt enable */
69
70/* STATUS_REG */
71#define CLK_UNCONNECTED (1<<0)
72#define PEND_WR_TIME (1<<2)
73#define PEND_WR_DATE (1<<3)
74#define LOST_WR_TIME (1<<4)
75#define LOST_WR_DATE (1<<5)
76#define RTC_INT_MASK (1<<31)
77#define STATUS_BUSY (PEND_WR_TIME | PEND_WR_DATE)
78#define STATUS_FAIL (LOST_WR_TIME | LOST_WR_DATE)
79
80struct spear_rtc_config {
81 struct rtc_device *rtc;
82 struct clk *clk;
83 spinlock_t lock;
84 void __iomem *ioaddr;
85 unsigned int irq_wake;
86};
87
88static inline void spear_rtc_clear_interrupt(struct spear_rtc_config *config)
89{
90 unsigned int val;
91 unsigned long flags;
92
93 spin_lock_irqsave(&config->lock, flags);
94 val = readl(config->ioaddr + STATUS_REG);
95 val |= RTC_INT_MASK;
96 writel(val, config->ioaddr + STATUS_REG);
97 spin_unlock_irqrestore(&config->lock, flags);
98}
99
100static inline void spear_rtc_enable_interrupt(struct spear_rtc_config *config)
101{
102 unsigned int val;
103
104 val = readl(config->ioaddr + CTRL_REG);
105 if (!(val & INT_ENABLE)) {
106 spear_rtc_clear_interrupt(config);
107 val |= INT_ENABLE;
108 writel(val, config->ioaddr + CTRL_REG);
109 }
110}
111
112static inline void spear_rtc_disable_interrupt(struct spear_rtc_config *config)
113{
114 unsigned int val;
115
116 val = readl(config->ioaddr + CTRL_REG);
117 if (val & INT_ENABLE) {
118 val &= ~INT_ENABLE;
119 writel(val, config->ioaddr + CTRL_REG);
120 }
121}
122
123static inline int is_write_complete(struct spear_rtc_config *config)
124{
125 int ret = 0;
126 unsigned long flags;
127
128 spin_lock_irqsave(&config->lock, flags);
129 if ((readl(config->ioaddr + STATUS_REG)) & STATUS_FAIL)
130 ret = -EIO;
131 spin_unlock_irqrestore(&config->lock, flags);
132
133 return ret;
134}
135
136static void rtc_wait_not_busy(struct spear_rtc_config *config)
137{
138 int status, count = 0;
139 unsigned long flags;
140
141 /* Assuming BUSY may stay active for 80 msec) */
142 for (count = 0; count < 80; count++) {
143 spin_lock_irqsave(&config->lock, flags);
144 status = readl(config->ioaddr + STATUS_REG);
145 spin_unlock_irqrestore(&config->lock, flags);
146 if ((status & STATUS_BUSY) == 0)
147 break;
148 /* check status busy, after each msec */
149 msleep(1);
150 }
151}
152
153static irqreturn_t spear_rtc_irq(int irq, void *dev_id)
154{
155 struct spear_rtc_config *config = dev_id;
156 unsigned long flags, events = 0;
157 unsigned int irq_data;
158
159 spin_lock_irqsave(&config->lock, flags);
160 irq_data = readl(config->ioaddr + STATUS_REG);
161 spin_unlock_irqrestore(&config->lock, flags);
162
163 if ((irq_data & RTC_INT_MASK)) {
164 spear_rtc_clear_interrupt(config);
165 events = RTC_IRQF | RTC_AF;
166 rtc_update_irq(config->rtc, 1, events);
167 return IRQ_HANDLED;
168 } else
169 return IRQ_NONE;
170
171}
172
173static void tm2bcd(struct rtc_time *tm)
174{
175 tm->tm_sec = bin2bcd(tm->tm_sec);
176 tm->tm_min = bin2bcd(tm->tm_min);
177 tm->tm_hour = bin2bcd(tm->tm_hour);
178 tm->tm_mday = bin2bcd(tm->tm_mday);
179 tm->tm_mon = bin2bcd(tm->tm_mon + 1);
180 tm->tm_year = bin2bcd(tm->tm_year);
181}
182
183static void bcd2tm(struct rtc_time *tm)
184{
185 tm->tm_sec = bcd2bin(tm->tm_sec);
186 tm->tm_min = bcd2bin(tm->tm_min);
187 tm->tm_hour = bcd2bin(tm->tm_hour);
188 tm->tm_mday = bcd2bin(tm->tm_mday);
189 tm->tm_mon = bcd2bin(tm->tm_mon) - 1;
190 /* epoch == 1900 */
191 tm->tm_year = bcd2bin(tm->tm_year);
192}
193
194/*
195 * spear_rtc_read_time - set the time
196 * @dev: rtc device in use
197 * @tm: holds date and time
198 *
199 * This function read time and date. On success it will return 0
200 * otherwise -ve error is returned.
201 */
202static int spear_rtc_read_time(struct device *dev, struct rtc_time *tm)
203{
204 struct spear_rtc_config *config = dev_get_drvdata(dev);
205 unsigned int time, date;
206
207 /* we don't report wday/yday/isdst ... */
208 rtc_wait_not_busy(config);
209
210 time = readl(config->ioaddr + TIME_REG);
211 date = readl(config->ioaddr + DATE_REG);
212 tm->tm_sec = (time >> SECOND_SHIFT) & SECOND_MASK;
213 tm->tm_min = (time >> MINUTE_SHIFT) & MIN_MASK;
214 tm->tm_hour = (time >> HOUR_SHIFT) & HOUR_MASK;
215 tm->tm_mday = (date >> MDAY_SHIFT) & DAY_MASK;
216 tm->tm_mon = (date >> MONTH_SHIFT) & MONTH_MASK;
217 tm->tm_year = (date >> YEAR_SHIFT) & YEAR_MASK;
218
219 bcd2tm(tm);
220 return 0;
221}
222
223/*
224 * spear_rtc_set_time - set the time
225 * @dev: rtc device in use
226 * @tm: holds date and time
227 *
228 * This function set time and date. On success it will return 0
229 * otherwise -ve error is returned.
230 */
231static int spear_rtc_set_time(struct device *dev, struct rtc_time *tm)
232{
233 struct spear_rtc_config *config = dev_get_drvdata(dev);
234 unsigned int time, date;
235
236 tm2bcd(tm);
237
238 rtc_wait_not_busy(config);
239 time = (tm->tm_sec << SECOND_SHIFT) | (tm->tm_min << MINUTE_SHIFT) |
240 (tm->tm_hour << HOUR_SHIFT);
241 date = (tm->tm_mday << MDAY_SHIFT) | (tm->tm_mon << MONTH_SHIFT) |
242 (tm->tm_year << YEAR_SHIFT);
243 writel(time, config->ioaddr + TIME_REG);
244 writel(date, config->ioaddr + DATE_REG);
245
246 return is_write_complete(config);
247}
248
249/*
250 * spear_rtc_read_alarm - read the alarm time
251 * @dev: rtc device in use
252 * @alm: holds alarm date and time
253 *
254 * This function read alarm time and date. On success it will return 0
255 * otherwise -ve error is returned.
256 */
257static int spear_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
258{
259 struct spear_rtc_config *config = dev_get_drvdata(dev);
260 unsigned int time, date;
261
262 rtc_wait_not_busy(config);
263
264 time = readl(config->ioaddr + ALARM_TIME_REG);
265 date = readl(config->ioaddr + ALARM_DATE_REG);
266 alm->time.tm_sec = (time >> SECOND_SHIFT) & SECOND_MASK;
267 alm->time.tm_min = (time >> MINUTE_SHIFT) & MIN_MASK;
268 alm->time.tm_hour = (time >> HOUR_SHIFT) & HOUR_MASK;
269 alm->time.tm_mday = (date >> MDAY_SHIFT) & DAY_MASK;
270 alm->time.tm_mon = (date >> MONTH_SHIFT) & MONTH_MASK;
271 alm->time.tm_year = (date >> YEAR_SHIFT) & YEAR_MASK;
272
273 bcd2tm(&alm->time);
274 alm->enabled = readl(config->ioaddr + CTRL_REG) & INT_ENABLE;
275
276 return 0;
277}
278
279/*
280 * spear_rtc_set_alarm - set the alarm time
281 * @dev: rtc device in use
282 * @alm: holds alarm date and time
283 *
284 * This function set alarm time and date. On success it will return 0
285 * otherwise -ve error is returned.
286 */
287static int spear_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
288{
289 struct spear_rtc_config *config = dev_get_drvdata(dev);
290 unsigned int time, date;
291 int err;
292
293 tm2bcd(&alm->time);
294
295 rtc_wait_not_busy(config);
296
297 time = (alm->time.tm_sec << SECOND_SHIFT) | (alm->time.tm_min <<
298 MINUTE_SHIFT) | (alm->time.tm_hour << HOUR_SHIFT);
299 date = (alm->time.tm_mday << MDAY_SHIFT) | (alm->time.tm_mon <<
300 MONTH_SHIFT) | (alm->time.tm_year << YEAR_SHIFT);
301
302 writel(time, config->ioaddr + ALARM_TIME_REG);
303 writel(date, config->ioaddr + ALARM_DATE_REG);
304 err = is_write_complete(config);
305 if (err < 0)
306 return err;
307
308 if (alm->enabled)
309 spear_rtc_enable_interrupt(config);
310 else
311 spear_rtc_disable_interrupt(config);
312
313 return 0;
314}
315
316static int spear_alarm_irq_enable(struct device *dev, unsigned int enabled)
317{
318 struct spear_rtc_config *config = dev_get_drvdata(dev);
319 int ret = 0;
320
321 spear_rtc_clear_interrupt(config);
322
323 switch (enabled) {
324 case 0:
325 /* alarm off */
326 spear_rtc_disable_interrupt(config);
327 break;
328 case 1:
329 /* alarm on */
330 spear_rtc_enable_interrupt(config);
331 break;
332 default:
333 ret = -EINVAL;
334 break;
335 }
336
337 return ret;
338}
339
340static const struct rtc_class_ops spear_rtc_ops = {
341 .read_time = spear_rtc_read_time,
342 .set_time = spear_rtc_set_time,
343 .read_alarm = spear_rtc_read_alarm,
344 .set_alarm = spear_rtc_set_alarm,
345 .alarm_irq_enable = spear_alarm_irq_enable,
346};
347
348static int spear_rtc_probe(struct platform_device *pdev)
349{
350 struct resource *res;
351 struct spear_rtc_config *config;
352 int status = 0;
353 int irq;
354
355 config = devm_kzalloc(&pdev->dev, sizeof(*config), GFP_KERNEL);
356 if (!config)
357 return -ENOMEM;
358
359 /* alarm irqs */
360 irq = platform_get_irq(pdev, 0);
361 if (irq < 0)
362 return irq;
363
364 status = devm_request_irq(&pdev->dev, irq, spear_rtc_irq, 0, pdev->name,
365 config);
366 if (status) {
367 dev_err(&pdev->dev, "Alarm interrupt IRQ%d already claimed\n",
368 irq);
369 return status;
370 }
371
372 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
373 config->ioaddr = devm_ioremap_resource(&pdev->dev, res);
374 if (IS_ERR(config->ioaddr))
375 return PTR_ERR(config->ioaddr);
376
377 config->clk = devm_clk_get(&pdev->dev, NULL);
378 if (IS_ERR(config->clk))
379 return PTR_ERR(config->clk);
380
381 status = clk_prepare_enable(config->clk);
382 if (status < 0)
383 return status;
384
385 spin_lock_init(&config->lock);
386 platform_set_drvdata(pdev, config);
387
388 config->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
389 &spear_rtc_ops, THIS_MODULE);
390 if (IS_ERR(config->rtc)) {
391 dev_err(&pdev->dev, "can't register RTC device, err %ld\n",
392 PTR_ERR(config->rtc));
393 status = PTR_ERR(config->rtc);
394 goto err_disable_clock;
395 }
396
397 config->rtc->uie_unsupported = 1;
398
399 if (!device_can_wakeup(&pdev->dev))
400 device_init_wakeup(&pdev->dev, 1);
401
402 return 0;
403
404err_disable_clock:
405 clk_disable_unprepare(config->clk);
406
407 return status;
408}
409
410static int spear_rtc_remove(struct platform_device *pdev)
411{
412 struct spear_rtc_config *config = platform_get_drvdata(pdev);
413
414 spear_rtc_disable_interrupt(config);
415 clk_disable_unprepare(config->clk);
416 device_init_wakeup(&pdev->dev, 0);
417
418 return 0;
419}
420
421#ifdef CONFIG_PM_SLEEP
422static int spear_rtc_suspend(struct device *dev)
423{
424 struct platform_device *pdev = to_platform_device(dev);
425 struct spear_rtc_config *config = platform_get_drvdata(pdev);
426 int irq;
427
428 irq = platform_get_irq(pdev, 0);
429 if (device_may_wakeup(&pdev->dev)) {
430 if (!enable_irq_wake(irq))
431 config->irq_wake = 1;
432 } else {
433 spear_rtc_disable_interrupt(config);
434 clk_disable(config->clk);
435 }
436
437 return 0;
438}
439
440static int spear_rtc_resume(struct device *dev)
441{
442 struct platform_device *pdev = to_platform_device(dev);
443 struct spear_rtc_config *config = platform_get_drvdata(pdev);
444 int irq;
445
446 irq = platform_get_irq(pdev, 0);
447
448 if (device_may_wakeup(&pdev->dev)) {
449 if (config->irq_wake) {
450 disable_irq_wake(irq);
451 config->irq_wake = 0;
452 }
453 } else {
454 clk_enable(config->clk);
455 spear_rtc_enable_interrupt(config);
456 }
457
458 return 0;
459}
460#endif
461
462static SIMPLE_DEV_PM_OPS(spear_rtc_pm_ops, spear_rtc_suspend, spear_rtc_resume);
463
464static void spear_rtc_shutdown(struct platform_device *pdev)
465{
466 struct spear_rtc_config *config = platform_get_drvdata(pdev);
467
468 spear_rtc_disable_interrupt(config);
469 clk_disable(config->clk);
470}
471
472#ifdef CONFIG_OF
473static const struct of_device_id spear_rtc_id_table[] = {
474 { .compatible = "st,spear600-rtc" },
475 {}
476};
477MODULE_DEVICE_TABLE(of, spear_rtc_id_table);
478#endif
479
480static struct platform_driver spear_rtc_driver = {
481 .probe = spear_rtc_probe,
482 .remove = spear_rtc_remove,
483 .shutdown = spear_rtc_shutdown,
484 .driver = {
485 .name = "rtc-spear",
486 .pm = &spear_rtc_pm_ops,
487 .of_match_table = of_match_ptr(spear_rtc_id_table),
488 },
489};
490
491module_platform_driver(spear_rtc_driver);
492
493MODULE_ALIAS("platform:rtc-spear");
494MODULE_AUTHOR("Rajeev Kumar <rajeev-dlh.kumar@st.com>");
495MODULE_DESCRIPTION("ST SPEAr Realtime Clock Driver (RTC)");
496MODULE_LICENSE("GPL");