Loading...
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * An rtc driver for the Dallas DS1511
4 *
5 * Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
6 * Copyright (C) 2007 Andrew Sharp <andy.sharp@lsi.com>
7 *
8 * Real time clock driver for the Dallas 1511 chip, which also
9 * contains a watchdog timer. There is a tiny amount of code that
10 * platform code could use to mess with the watchdog device a little
11 * bit, but not a full watchdog driver.
12 */
13
14#include <linux/bcd.h>
15#include <linux/init.h>
16#include <linux/kernel.h>
17#include <linux/gfp.h>
18#include <linux/delay.h>
19#include <linux/interrupt.h>
20#include <linux/rtc.h>
21#include <linux/platform_device.h>
22#include <linux/io.h>
23#include <linux/module.h>
24
25enum ds1511reg {
26 DS1511_SEC = 0x0,
27 DS1511_MIN = 0x1,
28 DS1511_HOUR = 0x2,
29 DS1511_DOW = 0x3,
30 DS1511_DOM = 0x4,
31 DS1511_MONTH = 0x5,
32 DS1511_YEAR = 0x6,
33 DS1511_CENTURY = 0x7,
34 DS1511_AM1_SEC = 0x8,
35 DS1511_AM2_MIN = 0x9,
36 DS1511_AM3_HOUR = 0xa,
37 DS1511_AM4_DATE = 0xb,
38 DS1511_WD_MSEC = 0xc,
39 DS1511_WD_SEC = 0xd,
40 DS1511_CONTROL_A = 0xe,
41 DS1511_CONTROL_B = 0xf,
42 DS1511_RAMADDR_LSB = 0x10,
43 DS1511_RAMDATA = 0x13
44};
45
46#define DS1511_BLF1 0x80
47#define DS1511_BLF2 0x40
48#define DS1511_PRS 0x20
49#define DS1511_PAB 0x10
50#define DS1511_TDF 0x08
51#define DS1511_KSF 0x04
52#define DS1511_WDF 0x02
53#define DS1511_IRQF 0x01
54#define DS1511_TE 0x80
55#define DS1511_CS 0x40
56#define DS1511_BME 0x20
57#define DS1511_TPE 0x10
58#define DS1511_TIE 0x08
59#define DS1511_KIE 0x04
60#define DS1511_WDE 0x02
61#define DS1511_WDS 0x01
62#define DS1511_RAM_MAX 0x100
63
64#define RTC_CMD DS1511_CONTROL_B
65#define RTC_CMD1 DS1511_CONTROL_A
66
67#define RTC_ALARM_SEC DS1511_AM1_SEC
68#define RTC_ALARM_MIN DS1511_AM2_MIN
69#define RTC_ALARM_HOUR DS1511_AM3_HOUR
70#define RTC_ALARM_DATE DS1511_AM4_DATE
71
72#define RTC_SEC DS1511_SEC
73#define RTC_MIN DS1511_MIN
74#define RTC_HOUR DS1511_HOUR
75#define RTC_DOW DS1511_DOW
76#define RTC_DOM DS1511_DOM
77#define RTC_MON DS1511_MONTH
78#define RTC_YEAR DS1511_YEAR
79#define RTC_CENTURY DS1511_CENTURY
80
81#define RTC_TIE DS1511_TIE
82#define RTC_TE DS1511_TE
83
84struct rtc_plat_data {
85 struct rtc_device *rtc;
86 void __iomem *ioaddr; /* virtual base address */
87 int irq;
88 unsigned int irqen;
89 int alrm_sec;
90 int alrm_min;
91 int alrm_hour;
92 int alrm_mday;
93 spinlock_t lock;
94};
95
96static DEFINE_SPINLOCK(ds1511_lock);
97
98static __iomem char *ds1511_base;
99static u32 reg_spacing = 1;
100
101static noinline void
102rtc_write(uint8_t val, uint32_t reg)
103{
104 writeb(val, ds1511_base + (reg * reg_spacing));
105}
106
107static inline void
108rtc_write_alarm(uint8_t val, enum ds1511reg reg)
109{
110 rtc_write((val | 0x80), reg);
111}
112
113static noinline uint8_t
114rtc_read(enum ds1511reg reg)
115{
116 return readb(ds1511_base + (reg * reg_spacing));
117}
118
119static inline void
120rtc_disable_update(void)
121{
122 rtc_write((rtc_read(RTC_CMD) & ~RTC_TE), RTC_CMD);
123}
124
125static void
126rtc_enable_update(void)
127{
128 rtc_write((rtc_read(RTC_CMD) | RTC_TE), RTC_CMD);
129}
130
131/*
132 * #define DS1511_WDOG_RESET_SUPPORT
133 *
134 * Uncomment this if you want to use these routines in
135 * some platform code.
136 */
137#ifdef DS1511_WDOG_RESET_SUPPORT
138/*
139 * just enough code to set the watchdog timer so that it
140 * will reboot the system
141 */
142void
143ds1511_wdog_set(unsigned long deciseconds)
144{
145 /*
146 * the wdog timer can take 99.99 seconds
147 */
148 deciseconds %= 10000;
149 /*
150 * set the wdog values in the wdog registers
151 */
152 rtc_write(bin2bcd(deciseconds % 100), DS1511_WD_MSEC);
153 rtc_write(bin2bcd(deciseconds / 100), DS1511_WD_SEC);
154 /*
155 * set wdog enable and wdog 'steering' bit to issue a reset
156 */
157 rtc_write(rtc_read(RTC_CMD) | DS1511_WDE | DS1511_WDS, RTC_CMD);
158}
159
160void
161ds1511_wdog_disable(void)
162{
163 /*
164 * clear wdog enable and wdog 'steering' bits
165 */
166 rtc_write(rtc_read(RTC_CMD) & ~(DS1511_WDE | DS1511_WDS), RTC_CMD);
167 /*
168 * clear the wdog counter
169 */
170 rtc_write(0, DS1511_WD_MSEC);
171 rtc_write(0, DS1511_WD_SEC);
172}
173#endif
174
175/*
176 * set the rtc chip's idea of the time.
177 * stupidly, some callers call with year unmolested;
178 * and some call with year = year - 1900. thanks.
179 */
180static int ds1511_rtc_set_time(struct device *dev, struct rtc_time *rtc_tm)
181{
182 u8 mon, day, dow, hrs, min, sec, yrs, cen;
183 unsigned long flags;
184
185 /*
186 * won't have to change this for a while
187 */
188 if (rtc_tm->tm_year < 1900)
189 rtc_tm->tm_year += 1900;
190
191 if (rtc_tm->tm_year < 1970)
192 return -EINVAL;
193
194 yrs = rtc_tm->tm_year % 100;
195 cen = rtc_tm->tm_year / 100;
196 mon = rtc_tm->tm_mon + 1; /* tm_mon starts at zero */
197 day = rtc_tm->tm_mday;
198 dow = rtc_tm->tm_wday & 0x7; /* automatic BCD */
199 hrs = rtc_tm->tm_hour;
200 min = rtc_tm->tm_min;
201 sec = rtc_tm->tm_sec;
202
203 if ((mon > 12) || (day == 0))
204 return -EINVAL;
205
206 if (day > rtc_month_days(rtc_tm->tm_mon, rtc_tm->tm_year))
207 return -EINVAL;
208
209 if ((hrs >= 24) || (min >= 60) || (sec >= 60))
210 return -EINVAL;
211
212 /*
213 * each register is a different number of valid bits
214 */
215 sec = bin2bcd(sec) & 0x7f;
216 min = bin2bcd(min) & 0x7f;
217 hrs = bin2bcd(hrs) & 0x3f;
218 day = bin2bcd(day) & 0x3f;
219 mon = bin2bcd(mon) & 0x1f;
220 yrs = bin2bcd(yrs) & 0xff;
221 cen = bin2bcd(cen) & 0xff;
222
223 spin_lock_irqsave(&ds1511_lock, flags);
224 rtc_disable_update();
225 rtc_write(cen, RTC_CENTURY);
226 rtc_write(yrs, RTC_YEAR);
227 rtc_write((rtc_read(RTC_MON) & 0xe0) | mon, RTC_MON);
228 rtc_write(day, RTC_DOM);
229 rtc_write(hrs, RTC_HOUR);
230 rtc_write(min, RTC_MIN);
231 rtc_write(sec, RTC_SEC);
232 rtc_write(dow, RTC_DOW);
233 rtc_enable_update();
234 spin_unlock_irqrestore(&ds1511_lock, flags);
235
236 return 0;
237}
238
239static int ds1511_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm)
240{
241 unsigned int century;
242 unsigned long flags;
243
244 spin_lock_irqsave(&ds1511_lock, flags);
245 rtc_disable_update();
246
247 rtc_tm->tm_sec = rtc_read(RTC_SEC) & 0x7f;
248 rtc_tm->tm_min = rtc_read(RTC_MIN) & 0x7f;
249 rtc_tm->tm_hour = rtc_read(RTC_HOUR) & 0x3f;
250 rtc_tm->tm_mday = rtc_read(RTC_DOM) & 0x3f;
251 rtc_tm->tm_wday = rtc_read(RTC_DOW) & 0x7;
252 rtc_tm->tm_mon = rtc_read(RTC_MON) & 0x1f;
253 rtc_tm->tm_year = rtc_read(RTC_YEAR) & 0x7f;
254 century = rtc_read(RTC_CENTURY);
255
256 rtc_enable_update();
257 spin_unlock_irqrestore(&ds1511_lock, flags);
258
259 rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
260 rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
261 rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
262 rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
263 rtc_tm->tm_wday = bcd2bin(rtc_tm->tm_wday);
264 rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
265 rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
266 century = bcd2bin(century) * 100;
267
268 /*
269 * Account for differences between how the RTC uses the values
270 * and how they are defined in a struct rtc_time;
271 */
272 century += rtc_tm->tm_year;
273 rtc_tm->tm_year = century - 1900;
274
275 rtc_tm->tm_mon--;
276
277 return 0;
278}
279
280/*
281 * write the alarm register settings
282 *
283 * we only have the use to interrupt every second, otherwise
284 * known as the update interrupt, or the interrupt if the whole
285 * date/hours/mins/secs matches. the ds1511 has many more
286 * permutations, but the kernel doesn't.
287 */
288static void
289ds1511_rtc_update_alarm(struct rtc_plat_data *pdata)
290{
291 unsigned long flags;
292
293 spin_lock_irqsave(&pdata->lock, flags);
294 rtc_write(pdata->alrm_mday < 0 || (pdata->irqen & RTC_UF) ?
295 0x80 : bin2bcd(pdata->alrm_mday) & 0x3f,
296 RTC_ALARM_DATE);
297 rtc_write(pdata->alrm_hour < 0 || (pdata->irqen & RTC_UF) ?
298 0x80 : bin2bcd(pdata->alrm_hour) & 0x3f,
299 RTC_ALARM_HOUR);
300 rtc_write(pdata->alrm_min < 0 || (pdata->irqen & RTC_UF) ?
301 0x80 : bin2bcd(pdata->alrm_min) & 0x7f,
302 RTC_ALARM_MIN);
303 rtc_write(pdata->alrm_sec < 0 || (pdata->irqen & RTC_UF) ?
304 0x80 : bin2bcd(pdata->alrm_sec) & 0x7f,
305 RTC_ALARM_SEC);
306 rtc_write(rtc_read(RTC_CMD) | (pdata->irqen ? RTC_TIE : 0), RTC_CMD);
307 rtc_read(RTC_CMD1); /* clear interrupts */
308 spin_unlock_irqrestore(&pdata->lock, flags);
309}
310
311static int
312ds1511_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
313{
314 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
315
316 if (pdata->irq <= 0)
317 return -EINVAL;
318
319 pdata->alrm_mday = alrm->time.tm_mday;
320 pdata->alrm_hour = alrm->time.tm_hour;
321 pdata->alrm_min = alrm->time.tm_min;
322 pdata->alrm_sec = alrm->time.tm_sec;
323 if (alrm->enabled)
324 pdata->irqen |= RTC_AF;
325
326 ds1511_rtc_update_alarm(pdata);
327 return 0;
328}
329
330static int
331ds1511_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
332{
333 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
334
335 if (pdata->irq <= 0)
336 return -EINVAL;
337
338 alrm->time.tm_mday = pdata->alrm_mday < 0 ? 0 : pdata->alrm_mday;
339 alrm->time.tm_hour = pdata->alrm_hour < 0 ? 0 : pdata->alrm_hour;
340 alrm->time.tm_min = pdata->alrm_min < 0 ? 0 : pdata->alrm_min;
341 alrm->time.tm_sec = pdata->alrm_sec < 0 ? 0 : pdata->alrm_sec;
342 alrm->enabled = (pdata->irqen & RTC_AF) ? 1 : 0;
343 return 0;
344}
345
346static irqreturn_t
347ds1511_interrupt(int irq, void *dev_id)
348{
349 struct platform_device *pdev = dev_id;
350 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
351 unsigned long events = 0;
352
353 spin_lock(&pdata->lock);
354 /*
355 * read and clear interrupt
356 */
357 if (rtc_read(RTC_CMD1) & DS1511_IRQF) {
358 events = RTC_IRQF;
359 if (rtc_read(RTC_ALARM_SEC) & 0x80)
360 events |= RTC_UF;
361 else
362 events |= RTC_AF;
363 rtc_update_irq(pdata->rtc, 1, events);
364 }
365 spin_unlock(&pdata->lock);
366 return events ? IRQ_HANDLED : IRQ_NONE;
367}
368
369static int ds1511_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
370{
371 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
372
373 if (pdata->irq <= 0)
374 return -EINVAL;
375 if (enabled)
376 pdata->irqen |= RTC_AF;
377 else
378 pdata->irqen &= ~RTC_AF;
379 ds1511_rtc_update_alarm(pdata);
380 return 0;
381}
382
383static const struct rtc_class_ops ds1511_rtc_ops = {
384 .read_time = ds1511_rtc_read_time,
385 .set_time = ds1511_rtc_set_time,
386 .read_alarm = ds1511_rtc_read_alarm,
387 .set_alarm = ds1511_rtc_set_alarm,
388 .alarm_irq_enable = ds1511_rtc_alarm_irq_enable,
389};
390
391static int ds1511_nvram_read(void *priv, unsigned int pos, void *buf,
392 size_t size)
393{
394 int i;
395
396 rtc_write(pos, DS1511_RAMADDR_LSB);
397 for (i = 0; i < size; i++)
398 *(char *)buf++ = rtc_read(DS1511_RAMDATA);
399
400 return 0;
401}
402
403static int ds1511_nvram_write(void *priv, unsigned int pos, void *buf,
404 size_t size)
405{
406 int i;
407
408 rtc_write(pos, DS1511_RAMADDR_LSB);
409 for (i = 0; i < size; i++)
410 rtc_write(*(char *)buf++, DS1511_RAMDATA);
411
412 return 0;
413}
414
415static int ds1511_rtc_probe(struct platform_device *pdev)
416{
417 struct rtc_plat_data *pdata;
418 int ret = 0;
419 struct nvmem_config ds1511_nvmem_cfg = {
420 .name = "ds1511_nvram",
421 .word_size = 1,
422 .stride = 1,
423 .size = DS1511_RAM_MAX,
424 .reg_read = ds1511_nvram_read,
425 .reg_write = ds1511_nvram_write,
426 .priv = &pdev->dev,
427 };
428
429 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
430 if (!pdata)
431 return -ENOMEM;
432
433 ds1511_base = devm_platform_ioremap_resource(pdev, 0);
434 if (IS_ERR(ds1511_base))
435 return PTR_ERR(ds1511_base);
436 pdata->ioaddr = ds1511_base;
437 pdata->irq = platform_get_irq(pdev, 0);
438
439 /*
440 * turn on the clock and the crystal, etc.
441 */
442 rtc_write(DS1511_BME, RTC_CMD);
443 rtc_write(0, RTC_CMD1);
444 /*
445 * clear the wdog counter
446 */
447 rtc_write(0, DS1511_WD_MSEC);
448 rtc_write(0, DS1511_WD_SEC);
449 /*
450 * start the clock
451 */
452 rtc_enable_update();
453
454 /*
455 * check for a dying bat-tree
456 */
457 if (rtc_read(RTC_CMD1) & DS1511_BLF1)
458 dev_warn(&pdev->dev, "voltage-low detected.\n");
459
460 spin_lock_init(&pdata->lock);
461 platform_set_drvdata(pdev, pdata);
462
463 pdata->rtc = devm_rtc_allocate_device(&pdev->dev);
464 if (IS_ERR(pdata->rtc))
465 return PTR_ERR(pdata->rtc);
466
467 pdata->rtc->ops = &ds1511_rtc_ops;
468
469 pdata->rtc->nvram_old_abi = true;
470
471 ret = rtc_register_device(pdata->rtc);
472 if (ret)
473 return ret;
474
475 rtc_nvmem_register(pdata->rtc, &ds1511_nvmem_cfg);
476
477 /*
478 * if the platform has an interrupt in mind for this device,
479 * then by all means, set it
480 */
481 if (pdata->irq > 0) {
482 rtc_read(RTC_CMD1);
483 if (devm_request_irq(&pdev->dev, pdata->irq, ds1511_interrupt,
484 IRQF_SHARED, pdev->name, pdev) < 0) {
485
486 dev_warn(&pdev->dev, "interrupt not available.\n");
487 pdata->irq = 0;
488 }
489 }
490
491 return 0;
492}
493
494/* work with hotplug and coldplug */
495MODULE_ALIAS("platform:ds1511");
496
497static struct platform_driver ds1511_rtc_driver = {
498 .probe = ds1511_rtc_probe,
499 .driver = {
500 .name = "ds1511",
501 },
502};
503
504module_platform_driver(ds1511_rtc_driver);
505
506MODULE_AUTHOR("Andrew Sharp <andy.sharp@lsi.com>");
507MODULE_DESCRIPTION("Dallas DS1511 RTC driver");
508MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * An rtc driver for the Dallas DS1511
4 *
5 * Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
6 * Copyright (C) 2007 Andrew Sharp <andy.sharp@lsi.com>
7 *
8 * Real time clock driver for the Dallas 1511 chip, which also
9 * contains a watchdog timer. There is a tiny amount of code that
10 * platform code could use to mess with the watchdog device a little
11 * bit, but not a full watchdog driver.
12 */
13
14#include <linux/bcd.h>
15#include <linux/init.h>
16#include <linux/kernel.h>
17#include <linux/gfp.h>
18#include <linux/delay.h>
19#include <linux/interrupt.h>
20#include <linux/rtc.h>
21#include <linux/platform_device.h>
22#include <linux/io.h>
23#include <linux/module.h>
24
25#define DS1511_SEC 0x0
26#define DS1511_MIN 0x1
27#define DS1511_HOUR 0x2
28#define DS1511_DOW 0x3
29#define DS1511_DOM 0x4
30#define DS1511_MONTH 0x5
31#define DS1511_YEAR 0x6
32#define DS1511_CENTURY 0x7
33#define DS1511_AM1_SEC 0x8
34#define DS1511_AM2_MIN 0x9
35#define DS1511_AM3_HOUR 0xa
36#define DS1511_AM4_DATE 0xb
37#define DS1511_WD_MSEC 0xc
38#define DS1511_WD_SEC 0xd
39#define DS1511_CONTROL_A 0xe
40#define DS1511_CONTROL_B 0xf
41#define DS1511_RAMADDR_LSB 0x10
42#define DS1511_RAMDATA 0x13
43
44#define DS1511_BLF1 0x80
45#define DS1511_BLF2 0x40
46#define DS1511_PRS 0x20
47#define DS1511_PAB 0x10
48#define DS1511_TDF 0x08
49#define DS1511_KSF 0x04
50#define DS1511_WDF 0x02
51#define DS1511_IRQF 0x01
52#define DS1511_TE 0x80
53#define DS1511_CS 0x40
54#define DS1511_BME 0x20
55#define DS1511_TPE 0x10
56#define DS1511_TIE 0x08
57#define DS1511_KIE 0x04
58#define DS1511_WDE 0x02
59#define DS1511_WDS 0x01
60#define DS1511_RAM_MAX 0x100
61
62struct ds1511_data {
63 struct rtc_device *rtc;
64 void __iomem *ioaddr; /* virtual base address */
65 int irq;
66 spinlock_t lock;
67};
68
69static DEFINE_SPINLOCK(ds1511_lock);
70
71static __iomem char *ds1511_base;
72static u32 reg_spacing = 1;
73
74static void rtc_write(uint8_t val, uint32_t reg)
75{
76 writeb(val, ds1511_base + (reg * reg_spacing));
77}
78
79static uint8_t rtc_read(uint32_t reg)
80{
81 return readb(ds1511_base + (reg * reg_spacing));
82}
83
84static void rtc_disable_update(void)
85{
86 rtc_write((rtc_read(DS1511_CONTROL_B) & ~DS1511_TE), DS1511_CONTROL_B);
87}
88
89static void rtc_enable_update(void)
90{
91 rtc_write((rtc_read(DS1511_CONTROL_B) | DS1511_TE), DS1511_CONTROL_B);
92}
93
94static int ds1511_rtc_set_time(struct device *dev, struct rtc_time *rtc_tm)
95{
96 u8 mon, day, dow, hrs, min, sec, yrs, cen;
97 unsigned long flags;
98
99 yrs = rtc_tm->tm_year % 100;
100 cen = 19 + rtc_tm->tm_year / 100;
101 mon = rtc_tm->tm_mon + 1; /* tm_mon starts at zero */
102 day = rtc_tm->tm_mday;
103 dow = rtc_tm->tm_wday & 0x7; /* automatic BCD */
104 hrs = rtc_tm->tm_hour;
105 min = rtc_tm->tm_min;
106 sec = rtc_tm->tm_sec;
107
108 /*
109 * each register is a different number of valid bits
110 */
111 sec = bin2bcd(sec) & 0x7f;
112 min = bin2bcd(min) & 0x7f;
113 hrs = bin2bcd(hrs) & 0x3f;
114 day = bin2bcd(day) & 0x3f;
115 mon = bin2bcd(mon) & 0x1f;
116 yrs = bin2bcd(yrs) & 0xff;
117 cen = bin2bcd(cen) & 0xff;
118
119 spin_lock_irqsave(&ds1511_lock, flags);
120 rtc_disable_update();
121 rtc_write(cen, DS1511_CENTURY);
122 rtc_write(yrs, DS1511_YEAR);
123 rtc_write((rtc_read(DS1511_MONTH) & 0xe0) | mon, DS1511_MONTH);
124 rtc_write(day, DS1511_DOM);
125 rtc_write(hrs, DS1511_HOUR);
126 rtc_write(min, DS1511_MIN);
127 rtc_write(sec, DS1511_SEC);
128 rtc_write(dow, DS1511_DOW);
129 rtc_enable_update();
130 spin_unlock_irqrestore(&ds1511_lock, flags);
131
132 return 0;
133}
134
135static int ds1511_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm)
136{
137 unsigned int century;
138 unsigned long flags;
139
140 spin_lock_irqsave(&ds1511_lock, flags);
141 rtc_disable_update();
142
143 rtc_tm->tm_sec = rtc_read(DS1511_SEC) & 0x7f;
144 rtc_tm->tm_min = rtc_read(DS1511_MIN) & 0x7f;
145 rtc_tm->tm_hour = rtc_read(DS1511_HOUR) & 0x3f;
146 rtc_tm->tm_mday = rtc_read(DS1511_DOM) & 0x3f;
147 rtc_tm->tm_wday = rtc_read(DS1511_DOW) & 0x7;
148 rtc_tm->tm_mon = rtc_read(DS1511_MONTH) & 0x1f;
149 rtc_tm->tm_year = rtc_read(DS1511_YEAR) & 0x7f;
150 century = rtc_read(DS1511_CENTURY);
151
152 rtc_enable_update();
153 spin_unlock_irqrestore(&ds1511_lock, flags);
154
155 rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
156 rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
157 rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
158 rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
159 rtc_tm->tm_wday = bcd2bin(rtc_tm->tm_wday);
160 rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
161 rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
162 century = bcd2bin(century) * 100;
163
164 /*
165 * Account for differences between how the RTC uses the values
166 * and how they are defined in a struct rtc_time;
167 */
168 century += rtc_tm->tm_year;
169 rtc_tm->tm_year = century - 1900;
170
171 rtc_tm->tm_mon--;
172
173 return 0;
174}
175
176static void ds1511_rtc_alarm_enable(unsigned int enabled)
177{
178 rtc_write(rtc_read(DS1511_CONTROL_B) | (enabled ? DS1511_TIE : 0), DS1511_CONTROL_B);
179}
180
181static int ds1511_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
182{
183 struct ds1511_data *ds1511 = dev_get_drvdata(dev);
184 unsigned long flags;
185
186 spin_lock_irqsave(&ds1511->lock, flags);
187 rtc_write(bin2bcd(alrm->time.tm_mday) & 0x3f, DS1511_AM4_DATE);
188 rtc_write(bin2bcd(alrm->time.tm_hour) & 0x3f, DS1511_AM3_HOUR);
189 rtc_write(bin2bcd(alrm->time.tm_min) & 0x7f, DS1511_AM2_MIN);
190 rtc_write(bin2bcd(alrm->time.tm_sec) & 0x7f, DS1511_AM1_SEC);
191 ds1511_rtc_alarm_enable(alrm->enabled);
192
193 rtc_read(DS1511_CONTROL_A); /* clear interrupts */
194 spin_unlock_irqrestore(&ds1511->lock, flags);
195
196 return 0;
197}
198
199static int ds1511_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
200{
201 alrm->time.tm_mday = bcd2bin(rtc_read(DS1511_AM4_DATE) & 0x3f);
202 alrm->time.tm_hour = bcd2bin(rtc_read(DS1511_AM3_HOUR) & 0x3f);
203 alrm->time.tm_min = bcd2bin(rtc_read(DS1511_AM2_MIN) & 0x7f);
204 alrm->time.tm_sec = bcd2bin(rtc_read(DS1511_AM1_SEC) & 0x7f);
205 alrm->enabled = !!(rtc_read(DS1511_CONTROL_B) & DS1511_TIE);
206
207 return 0;
208}
209
210static irqreturn_t ds1511_interrupt(int irq, void *dev_id)
211{
212 struct platform_device *pdev = dev_id;
213 struct ds1511_data *ds1511 = platform_get_drvdata(pdev);
214 unsigned long events = 0;
215
216 spin_lock(&ds1511->lock);
217 /*
218 * read and clear interrupt
219 */
220 if (rtc_read(DS1511_CONTROL_A) & DS1511_IRQF) {
221 events = RTC_IRQF | RTC_AF;
222 rtc_update_irq(ds1511->rtc, 1, events);
223 }
224 spin_unlock(&ds1511->lock);
225 return events ? IRQ_HANDLED : IRQ_NONE;
226}
227
228static int ds1511_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
229{
230 struct ds1511_data *ds1511 = dev_get_drvdata(dev);
231 unsigned long flags;
232
233 spin_lock_irqsave(&ds1511->lock, flags);
234 ds1511_rtc_alarm_enable(enabled);
235 spin_unlock_irqrestore(&ds1511->lock, flags);
236
237 return 0;
238}
239
240static const struct rtc_class_ops ds1511_rtc_ops = {
241 .read_time = ds1511_rtc_read_time,
242 .set_time = ds1511_rtc_set_time,
243 .read_alarm = ds1511_rtc_read_alarm,
244 .set_alarm = ds1511_rtc_set_alarm,
245 .alarm_irq_enable = ds1511_rtc_alarm_irq_enable,
246};
247
248static int ds1511_nvram_read(void *priv, unsigned int pos, void *buf,
249 size_t size)
250{
251 int i;
252
253 rtc_write(pos, DS1511_RAMADDR_LSB);
254 for (i = 0; i < size; i++)
255 *(char *)buf++ = rtc_read(DS1511_RAMDATA);
256
257 return 0;
258}
259
260static int ds1511_nvram_write(void *priv, unsigned int pos, void *buf,
261 size_t size)
262{
263 int i;
264
265 rtc_write(pos, DS1511_RAMADDR_LSB);
266 for (i = 0; i < size; i++)
267 rtc_write(*(char *)buf++, DS1511_RAMDATA);
268
269 return 0;
270}
271
272static int ds1511_rtc_probe(struct platform_device *pdev)
273{
274 struct ds1511_data *ds1511;
275 int ret = 0;
276 struct nvmem_config ds1511_nvmem_cfg = {
277 .name = "ds1511_nvram",
278 .word_size = 1,
279 .stride = 1,
280 .size = DS1511_RAM_MAX,
281 .reg_read = ds1511_nvram_read,
282 .reg_write = ds1511_nvram_write,
283 .priv = &pdev->dev,
284 };
285
286 ds1511 = devm_kzalloc(&pdev->dev, sizeof(*ds1511), GFP_KERNEL);
287 if (!ds1511)
288 return -ENOMEM;
289
290 ds1511_base = devm_platform_ioremap_resource(pdev, 0);
291 if (IS_ERR(ds1511_base))
292 return PTR_ERR(ds1511_base);
293 ds1511->ioaddr = ds1511_base;
294 ds1511->irq = platform_get_irq(pdev, 0);
295
296 /*
297 * turn on the clock and the crystal, etc.
298 */
299 rtc_write(DS1511_BME, DS1511_CONTROL_B);
300 rtc_write(0, DS1511_CONTROL_A);
301 /*
302 * clear the wdog counter
303 */
304 rtc_write(0, DS1511_WD_MSEC);
305 rtc_write(0, DS1511_WD_SEC);
306 /*
307 * start the clock
308 */
309 rtc_enable_update();
310
311 /*
312 * check for a dying bat-tree
313 */
314 if (rtc_read(DS1511_CONTROL_A) & DS1511_BLF1)
315 dev_warn(&pdev->dev, "voltage-low detected.\n");
316
317 spin_lock_init(&ds1511->lock);
318 platform_set_drvdata(pdev, ds1511);
319
320 ds1511->rtc = devm_rtc_allocate_device(&pdev->dev);
321 if (IS_ERR(ds1511->rtc))
322 return PTR_ERR(ds1511->rtc);
323
324 ds1511->rtc->ops = &ds1511_rtc_ops;
325 ds1511->rtc->range_max = RTC_TIMESTAMP_END_2099;
326 ds1511->rtc->alarm_offset_max = 28 * 24 * 60 * 60 - 1;
327
328 /*
329 * if the platform has an interrupt in mind for this device,
330 * then by all means, set it
331 */
332 if (ds1511->irq > 0) {
333 rtc_read(DS1511_CONTROL_A);
334 if (devm_request_irq(&pdev->dev, ds1511->irq, ds1511_interrupt,
335 IRQF_SHARED, pdev->name, pdev) < 0) {
336
337 dev_warn(&pdev->dev, "interrupt not available.\n");
338 ds1511->irq = 0;
339 }
340 }
341
342 if (ds1511->irq == 0)
343 clear_bit(RTC_FEATURE_ALARM, ds1511->rtc->features);
344
345 ret = devm_rtc_register_device(ds1511->rtc);
346 if (ret)
347 return ret;
348
349 devm_rtc_nvmem_register(ds1511->rtc, &ds1511_nvmem_cfg);
350
351 return 0;
352}
353
354/* work with hotplug and coldplug */
355MODULE_ALIAS("platform:ds1511");
356
357static struct platform_driver ds1511_rtc_driver = {
358 .probe = ds1511_rtc_probe,
359 .driver = {
360 .name = "ds1511",
361 },
362};
363
364module_platform_driver(ds1511_rtc_driver);
365
366MODULE_AUTHOR("Andrew Sharp <andy.sharp@lsi.com>");
367MODULE_DESCRIPTION("Dallas DS1511 RTC driver");
368MODULE_LICENSE("GPL");