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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// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * drivers/rtc/rtc-spear.c
4 *
5 * Copyright (C) 2010 ST Microelectronics
6 * Rajeev Kumar<rajeev-dlh.kumar@st.com>
7 */
8
9#include <linux/bcd.h>
10#include <linux/clk.h>
11#include <linux/delay.h>
12#include <linux/init.h>
13#include <linux/io.h>
14#include <linux/irq.h>
15#include <linux/module.h>
16#include <linux/of.h>
17#include <linux/platform_device.h>
18#include <linux/rtc.h>
19#include <linux/slab.h>
20#include <linux/spinlock.h>
21
22/* RTC registers */
23#define TIME_REG 0x00
24#define DATE_REG 0x04
25#define ALARM_TIME_REG 0x08
26#define ALARM_DATE_REG 0x0C
27#define CTRL_REG 0x10
28#define STATUS_REG 0x14
29
30/* TIME_REG & ALARM_TIME_REG */
31#define SECONDS_UNITS (0xf<<0) /* seconds units position */
32#define SECONDS_TENS (0x7<<4) /* seconds tens position */
33#define MINUTES_UNITS (0xf<<8) /* minutes units position */
34#define MINUTES_TENS (0x7<<12) /* minutes tens position */
35#define HOURS_UNITS (0xf<<16) /* hours units position */
36#define HOURS_TENS (0x3<<20) /* hours tens position */
37
38/* DATE_REG & ALARM_DATE_REG */
39#define DAYS_UNITS (0xf<<0) /* days units position */
40#define DAYS_TENS (0x3<<4) /* days tens position */
41#define MONTHS_UNITS (0xf<<8) /* months units position */
42#define MONTHS_TENS (0x1<<12) /* months tens position */
43#define YEARS_UNITS (0xf<<16) /* years units position */
44#define YEARS_TENS (0xf<<20) /* years tens position */
45#define YEARS_HUNDREDS (0xf<<24) /* years hundereds position */
46#define YEARS_MILLENIUMS (0xf<<28) /* years millenium position */
47
48/* MASK SHIFT TIME_REG & ALARM_TIME_REG*/
49#define SECOND_SHIFT 0x00 /* seconds units */
50#define MINUTE_SHIFT 0x08 /* minutes units position */
51#define HOUR_SHIFT 0x10 /* hours units position */
52#define MDAY_SHIFT 0x00 /* Month day shift */
53#define MONTH_SHIFT 0x08 /* Month shift */
54#define YEAR_SHIFT 0x10 /* Year shift */
55
56#define SECOND_MASK 0x7F
57#define MIN_MASK 0x7F
58#define HOUR_MASK 0x3F
59#define DAY_MASK 0x3F
60#define MONTH_MASK 0x7F
61#define YEAR_MASK 0xFFFF
62
63/* date reg equal to time reg, for debug only */
64#define TIME_BYP (1<<9)
65#define INT_ENABLE (1<<31) /* interrupt enable */
66
67/* STATUS_REG */
68#define CLK_UNCONNECTED (1<<0)
69#define PEND_WR_TIME (1<<2)
70#define PEND_WR_DATE (1<<3)
71#define LOST_WR_TIME (1<<4)
72#define LOST_WR_DATE (1<<5)
73#define RTC_INT_MASK (1<<31)
74#define STATUS_BUSY (PEND_WR_TIME | PEND_WR_DATE)
75#define STATUS_FAIL (LOST_WR_TIME | LOST_WR_DATE)
76
77struct spear_rtc_config {
78 struct rtc_device *rtc;
79 struct clk *clk;
80 spinlock_t lock;
81 void __iomem *ioaddr;
82 unsigned int irq_wake;
83};
84
85static inline void spear_rtc_clear_interrupt(struct spear_rtc_config *config)
86{
87 unsigned int val;
88 unsigned long flags;
89
90 spin_lock_irqsave(&config->lock, flags);
91 val = readl(config->ioaddr + STATUS_REG);
92 val |= RTC_INT_MASK;
93 writel(val, config->ioaddr + STATUS_REG);
94 spin_unlock_irqrestore(&config->lock, flags);
95}
96
97static inline void spear_rtc_enable_interrupt(struct spear_rtc_config *config)
98{
99 unsigned int val;
100
101 val = readl(config->ioaddr + CTRL_REG);
102 if (!(val & INT_ENABLE)) {
103 spear_rtc_clear_interrupt(config);
104 val |= INT_ENABLE;
105 writel(val, config->ioaddr + CTRL_REG);
106 }
107}
108
109static inline void spear_rtc_disable_interrupt(struct spear_rtc_config *config)
110{
111 unsigned int val;
112
113 val = readl(config->ioaddr + CTRL_REG);
114 if (val & INT_ENABLE) {
115 val &= ~INT_ENABLE;
116 writel(val, config->ioaddr + CTRL_REG);
117 }
118}
119
120static inline int is_write_complete(struct spear_rtc_config *config)
121{
122 int ret = 0;
123 unsigned long flags;
124
125 spin_lock_irqsave(&config->lock, flags);
126 if ((readl(config->ioaddr + STATUS_REG)) & STATUS_FAIL)
127 ret = -EIO;
128 spin_unlock_irqrestore(&config->lock, flags);
129
130 return ret;
131}
132
133static void rtc_wait_not_busy(struct spear_rtc_config *config)
134{
135 int status, count = 0;
136 unsigned long flags;
137
138 /* Assuming BUSY may stay active for 80 msec) */
139 for (count = 0; count < 80; count++) {
140 spin_lock_irqsave(&config->lock, flags);
141 status = readl(config->ioaddr + STATUS_REG);
142 spin_unlock_irqrestore(&config->lock, flags);
143 if ((status & STATUS_BUSY) == 0)
144 break;
145 /* check status busy, after each msec */
146 msleep(1);
147 }
148}
149
150static irqreturn_t spear_rtc_irq(int irq, void *dev_id)
151{
152 struct spear_rtc_config *config = dev_id;
153 unsigned long events = 0;
154 unsigned int irq_data;
155
156 spin_lock(&config->lock);
157 irq_data = readl(config->ioaddr + STATUS_REG);
158 spin_unlock(&config->lock);
159
160 if ((irq_data & RTC_INT_MASK)) {
161 spear_rtc_clear_interrupt(config);
162 events = RTC_IRQF | RTC_AF;
163 rtc_update_irq(config->rtc, 1, events);
164 return IRQ_HANDLED;
165 } else
166 return IRQ_NONE;
167
168}
169
170static void tm2bcd(struct rtc_time *tm)
171{
172 tm->tm_sec = bin2bcd(tm->tm_sec);
173 tm->tm_min = bin2bcd(tm->tm_min);
174 tm->tm_hour = bin2bcd(tm->tm_hour);
175 tm->tm_mday = bin2bcd(tm->tm_mday);
176 tm->tm_mon = bin2bcd(tm->tm_mon + 1);
177 tm->tm_year = bin2bcd(tm->tm_year);
178}
179
180static void bcd2tm(struct rtc_time *tm)
181{
182 tm->tm_sec = bcd2bin(tm->tm_sec);
183 tm->tm_min = bcd2bin(tm->tm_min);
184 tm->tm_hour = bcd2bin(tm->tm_hour);
185 tm->tm_mday = bcd2bin(tm->tm_mday);
186 tm->tm_mon = bcd2bin(tm->tm_mon) - 1;
187 /* epoch == 1900 */
188 tm->tm_year = bcd2bin(tm->tm_year);
189}
190
191/*
192 * spear_rtc_read_time - set the time
193 * @dev: rtc device in use
194 * @tm: holds date and time
195 *
196 * This function read time and date. On success it will return 0
197 * otherwise -ve error is returned.
198 */
199static int spear_rtc_read_time(struct device *dev, struct rtc_time *tm)
200{
201 struct spear_rtc_config *config = dev_get_drvdata(dev);
202 unsigned int time, date;
203
204 /* we don't report wday/yday/isdst ... */
205 rtc_wait_not_busy(config);
206
207 do {
208 time = readl(config->ioaddr + TIME_REG);
209 date = readl(config->ioaddr + DATE_REG);
210 } while (time == readl(config->ioaddr + TIME_REG));
211 tm->tm_sec = (time >> SECOND_SHIFT) & SECOND_MASK;
212 tm->tm_min = (time >> MINUTE_SHIFT) & MIN_MASK;
213 tm->tm_hour = (time >> HOUR_SHIFT) & HOUR_MASK;
214 tm->tm_mday = (date >> MDAY_SHIFT) & DAY_MASK;
215 tm->tm_mon = (date >> MONTH_SHIFT) & MONTH_MASK;
216 tm->tm_year = (date >> YEAR_SHIFT) & YEAR_MASK;
217
218 bcd2tm(tm);
219 return 0;
220}
221
222/*
223 * spear_rtc_set_time - set the time
224 * @dev: rtc device in use
225 * @tm: holds date and time
226 *
227 * This function set time and date. On success it will return 0
228 * otherwise -ve error is returned.
229 */
230static int spear_rtc_set_time(struct device *dev, struct rtc_time *tm)
231{
232 struct spear_rtc_config *config = dev_get_drvdata(dev);
233 unsigned int time, date;
234
235 tm2bcd(tm);
236
237 rtc_wait_not_busy(config);
238 time = (tm->tm_sec << SECOND_SHIFT) | (tm->tm_min << MINUTE_SHIFT) |
239 (tm->tm_hour << HOUR_SHIFT);
240 date = (tm->tm_mday << MDAY_SHIFT) | (tm->tm_mon << MONTH_SHIFT) |
241 (tm->tm_year << YEAR_SHIFT);
242 writel(time, config->ioaddr + TIME_REG);
243 writel(date, config->ioaddr + DATE_REG);
244
245 return is_write_complete(config);
246}
247
248/*
249 * spear_rtc_read_alarm - read the alarm time
250 * @dev: rtc device in use
251 * @alm: holds alarm date and time
252 *
253 * This function read alarm time and date. On success it will return 0
254 * otherwise -ve error is returned.
255 */
256static int spear_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
257{
258 struct spear_rtc_config *config = dev_get_drvdata(dev);
259 unsigned int time, date;
260
261 rtc_wait_not_busy(config);
262
263 time = readl(config->ioaddr + ALARM_TIME_REG);
264 date = readl(config->ioaddr + ALARM_DATE_REG);
265 alm->time.tm_sec = (time >> SECOND_SHIFT) & SECOND_MASK;
266 alm->time.tm_min = (time >> MINUTE_SHIFT) & MIN_MASK;
267 alm->time.tm_hour = (time >> HOUR_SHIFT) & HOUR_MASK;
268 alm->time.tm_mday = (date >> MDAY_SHIFT) & DAY_MASK;
269 alm->time.tm_mon = (date >> MONTH_SHIFT) & MONTH_MASK;
270 alm->time.tm_year = (date >> YEAR_SHIFT) & YEAR_MASK;
271
272 bcd2tm(&alm->time);
273 alm->enabled = readl(config->ioaddr + CTRL_REG) & INT_ENABLE;
274
275 return 0;
276}
277
278/*
279 * spear_rtc_set_alarm - set the alarm time
280 * @dev: rtc device in use
281 * @alm: holds alarm date and time
282 *
283 * This function set alarm time and date. On success it will return 0
284 * otherwise -ve error is returned.
285 */
286static int spear_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
287{
288 struct spear_rtc_config *config = dev_get_drvdata(dev);
289 unsigned int time, date;
290 int err;
291
292 tm2bcd(&alm->time);
293
294 rtc_wait_not_busy(config);
295
296 time = (alm->time.tm_sec << SECOND_SHIFT) | (alm->time.tm_min <<
297 MINUTE_SHIFT) | (alm->time.tm_hour << HOUR_SHIFT);
298 date = (alm->time.tm_mday << MDAY_SHIFT) | (alm->time.tm_mon <<
299 MONTH_SHIFT) | (alm->time.tm_year << YEAR_SHIFT);
300
301 writel(time, config->ioaddr + ALARM_TIME_REG);
302 writel(date, config->ioaddr + ALARM_DATE_REG);
303 err = is_write_complete(config);
304 if (err < 0)
305 return err;
306
307 if (alm->enabled)
308 spear_rtc_enable_interrupt(config);
309 else
310 spear_rtc_disable_interrupt(config);
311
312 return 0;
313}
314
315static int spear_alarm_irq_enable(struct device *dev, unsigned int enabled)
316{
317 struct spear_rtc_config *config = dev_get_drvdata(dev);
318 int ret = 0;
319
320 spear_rtc_clear_interrupt(config);
321
322 switch (enabled) {
323 case 0:
324 /* alarm off */
325 spear_rtc_disable_interrupt(config);
326 break;
327 case 1:
328 /* alarm on */
329 spear_rtc_enable_interrupt(config);
330 break;
331 default:
332 ret = -EINVAL;
333 break;
334 }
335
336 return ret;
337}
338
339static const struct rtc_class_ops spear_rtc_ops = {
340 .read_time = spear_rtc_read_time,
341 .set_time = spear_rtc_set_time,
342 .read_alarm = spear_rtc_read_alarm,
343 .set_alarm = spear_rtc_set_alarm,
344 .alarm_irq_enable = spear_alarm_irq_enable,
345};
346
347static int spear_rtc_probe(struct platform_device *pdev)
348{
349 struct spear_rtc_config *config;
350 int status = 0;
351 int irq;
352
353 config = devm_kzalloc(&pdev->dev, sizeof(*config), GFP_KERNEL);
354 if (!config)
355 return -ENOMEM;
356
357 config->rtc = devm_rtc_allocate_device(&pdev->dev);
358 if (IS_ERR(config->rtc))
359 return PTR_ERR(config->rtc);
360
361 /* alarm irqs */
362 irq = platform_get_irq(pdev, 0);
363 if (irq < 0)
364 return irq;
365
366 status = devm_request_irq(&pdev->dev, irq, spear_rtc_irq, 0, pdev->name,
367 config);
368 if (status) {
369 dev_err(&pdev->dev, "Alarm interrupt IRQ%d already claimed\n",
370 irq);
371 return status;
372 }
373
374 config->ioaddr = devm_platform_ioremap_resource(pdev, 0);
375 if (IS_ERR(config->ioaddr))
376 return PTR_ERR(config->ioaddr);
377
378 config->clk = devm_clk_get(&pdev->dev, NULL);
379 if (IS_ERR(config->clk))
380 return PTR_ERR(config->clk);
381
382 status = clk_prepare_enable(config->clk);
383 if (status < 0)
384 return status;
385
386 spin_lock_init(&config->lock);
387 platform_set_drvdata(pdev, config);
388
389 config->rtc->ops = &spear_rtc_ops;
390 config->rtc->range_min = RTC_TIMESTAMP_BEGIN_0000;
391 config->rtc->range_max = RTC_TIMESTAMP_END_9999;
392
393 status = devm_rtc_register_device(config->rtc);
394 if (status)
395 goto err_disable_clock;
396
397 if (!device_can_wakeup(&pdev->dev))
398 device_init_wakeup(&pdev->dev, 1);
399
400 return 0;
401
402err_disable_clock:
403 clk_disable_unprepare(config->clk);
404
405 return status;
406}
407
408static void spear_rtc_remove(struct platform_device *pdev)
409{
410 struct spear_rtc_config *config = platform_get_drvdata(pdev);
411
412 spear_rtc_disable_interrupt(config);
413 clk_disable_unprepare(config->clk);
414 device_init_wakeup(&pdev->dev, 0);
415}
416
417#ifdef CONFIG_PM_SLEEP
418static int spear_rtc_suspend(struct device *dev)
419{
420 struct platform_device *pdev = to_platform_device(dev);
421 struct spear_rtc_config *config = platform_get_drvdata(pdev);
422 int irq;
423
424 irq = platform_get_irq(pdev, 0);
425 if (device_may_wakeup(&pdev->dev)) {
426 if (!enable_irq_wake(irq))
427 config->irq_wake = 1;
428 } else {
429 spear_rtc_disable_interrupt(config);
430 clk_disable(config->clk);
431 }
432
433 return 0;
434}
435
436static int spear_rtc_resume(struct device *dev)
437{
438 struct platform_device *pdev = to_platform_device(dev);
439 struct spear_rtc_config *config = platform_get_drvdata(pdev);
440 int irq;
441
442 irq = platform_get_irq(pdev, 0);
443
444 if (device_may_wakeup(&pdev->dev)) {
445 if (config->irq_wake) {
446 disable_irq_wake(irq);
447 config->irq_wake = 0;
448 }
449 } else {
450 clk_enable(config->clk);
451 spear_rtc_enable_interrupt(config);
452 }
453
454 return 0;
455}
456#endif
457
458static SIMPLE_DEV_PM_OPS(spear_rtc_pm_ops, spear_rtc_suspend, spear_rtc_resume);
459
460static void spear_rtc_shutdown(struct platform_device *pdev)
461{
462 struct spear_rtc_config *config = platform_get_drvdata(pdev);
463
464 spear_rtc_disable_interrupt(config);
465 clk_disable(config->clk);
466}
467
468#ifdef CONFIG_OF
469static const struct of_device_id spear_rtc_id_table[] = {
470 { .compatible = "st,spear600-rtc" },
471 {}
472};
473MODULE_DEVICE_TABLE(of, spear_rtc_id_table);
474#endif
475
476static struct platform_driver spear_rtc_driver = {
477 .probe = spear_rtc_probe,
478 .remove = spear_rtc_remove,
479 .shutdown = spear_rtc_shutdown,
480 .driver = {
481 .name = "rtc-spear",
482 .pm = &spear_rtc_pm_ops,
483 .of_match_table = of_match_ptr(spear_rtc_id_table),
484 },
485};
486
487module_platform_driver(spear_rtc_driver);
488
489MODULE_ALIAS("platform:rtc-spear");
490MODULE_AUTHOR("Rajeev Kumar <rajeev-dlh.kumar@st.com>");
491MODULE_DESCRIPTION("ST SPEAr Realtime Clock Driver (RTC)");
492MODULE_LICENSE("GPL");