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1/*
2 * Copyright (C) ST-Ericsson SA 2010
3 *
4 * License terms: GNU General Public License (GPL) version 2
5 * Author: Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>
6 *
7 * RTC clock driver for the RTC part of the AB8500 Power management chip.
8 * Based on RTC clock driver for the AB3100 Analog Baseband Chip by
9 * Linus Walleij <linus.walleij@stericsson.com>
10 */
11
12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/platform_device.h>
16#include <linux/rtc.h>
17#include <linux/mfd/abx500.h>
18#include <linux/mfd/abx500/ab8500.h>
19#include <linux/delay.h>
20#include <linux/of.h>
21
22#define AB8500_RTC_SOFF_STAT_REG 0x00
23#define AB8500_RTC_CC_CONF_REG 0x01
24#define AB8500_RTC_READ_REQ_REG 0x02
25#define AB8500_RTC_WATCH_TSECMID_REG 0x03
26#define AB8500_RTC_WATCH_TSECHI_REG 0x04
27#define AB8500_RTC_WATCH_TMIN_LOW_REG 0x05
28#define AB8500_RTC_WATCH_TMIN_MID_REG 0x06
29#define AB8500_RTC_WATCH_TMIN_HI_REG 0x07
30#define AB8500_RTC_ALRM_MIN_LOW_REG 0x08
31#define AB8500_RTC_ALRM_MIN_MID_REG 0x09
32#define AB8500_RTC_ALRM_MIN_HI_REG 0x0A
33#define AB8500_RTC_STAT_REG 0x0B
34#define AB8500_RTC_BKUP_CHG_REG 0x0C
35#define AB8500_RTC_FORCE_BKUP_REG 0x0D
36#define AB8500_RTC_CALIB_REG 0x0E
37#define AB8500_RTC_SWITCH_STAT_REG 0x0F
38
39/* RtcReadRequest bits */
40#define RTC_READ_REQUEST 0x01
41#define RTC_WRITE_REQUEST 0x02
42
43/* RtcCtrl bits */
44#define RTC_ALARM_ENA 0x04
45#define RTC_STATUS_DATA 0x01
46
47#define COUNTS_PER_SEC (0xF000 / 60)
48#define AB8500_RTC_EPOCH 2000
49
50static const u8 ab8500_rtc_time_regs[] = {
51 AB8500_RTC_WATCH_TMIN_HI_REG, AB8500_RTC_WATCH_TMIN_MID_REG,
52 AB8500_RTC_WATCH_TMIN_LOW_REG, AB8500_RTC_WATCH_TSECHI_REG,
53 AB8500_RTC_WATCH_TSECMID_REG
54};
55
56static const u8 ab8500_rtc_alarm_regs[] = {
57 AB8500_RTC_ALRM_MIN_HI_REG, AB8500_RTC_ALRM_MIN_MID_REG,
58 AB8500_RTC_ALRM_MIN_LOW_REG
59};
60
61/* Calculate the seconds from 1970 to 01-01-2000 00:00:00 */
62static unsigned long get_elapsed_seconds(int year)
63{
64 unsigned long secs;
65 struct rtc_time tm = {
66 .tm_year = year - 1900,
67 .tm_mday = 1,
68 };
69
70 /*
71 * This function calculates secs from 1970 and not from
72 * 1900, even if we supply the offset from year 1900.
73 */
74 rtc_tm_to_time(&tm, &secs);
75 return secs;
76}
77
78static int ab8500_rtc_read_time(struct device *dev, struct rtc_time *tm)
79{
80 unsigned long timeout = jiffies + HZ;
81 int retval, i;
82 unsigned long mins, secs;
83 unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
84 u8 value;
85
86 /* Request a data read */
87 retval = abx500_set_register_interruptible(dev,
88 AB8500_RTC, AB8500_RTC_READ_REQ_REG, RTC_READ_REQUEST);
89 if (retval < 0)
90 return retval;
91
92 /* Early AB8500 chips will not clear the rtc read request bit */
93 if (abx500_get_chip_id(dev) == 0) {
94 usleep_range(1000, 1000);
95 } else {
96 /* Wait for some cycles after enabling the rtc read in ab8500 */
97 while (time_before(jiffies, timeout)) {
98 retval = abx500_get_register_interruptible(dev,
99 AB8500_RTC, AB8500_RTC_READ_REQ_REG, &value);
100 if (retval < 0)
101 return retval;
102
103 if (!(value & RTC_READ_REQUEST))
104 break;
105
106 usleep_range(1000, 5000);
107 }
108 }
109
110 /* Read the Watchtime registers */
111 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {
112 retval = abx500_get_register_interruptible(dev,
113 AB8500_RTC, ab8500_rtc_time_regs[i], &value);
114 if (retval < 0)
115 return retval;
116 buf[i] = value;
117 }
118
119 mins = (buf[0] << 16) | (buf[1] << 8) | buf[2];
120
121 secs = (buf[3] << 8) | buf[4];
122 secs = secs / COUNTS_PER_SEC;
123 secs = secs + (mins * 60);
124
125 /* Add back the initially subtracted number of seconds */
126 secs += get_elapsed_seconds(AB8500_RTC_EPOCH);
127
128 rtc_time_to_tm(secs, tm);
129 return rtc_valid_tm(tm);
130}
131
132static int ab8500_rtc_set_time(struct device *dev, struct rtc_time *tm)
133{
134 int retval, i;
135 unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
136 unsigned long no_secs, no_mins, secs = 0;
137
138 if (tm->tm_year < (AB8500_RTC_EPOCH - 1900)) {
139 dev_dbg(dev, "year should be equal to or greater than %d\n",
140 AB8500_RTC_EPOCH);
141 return -EINVAL;
142 }
143
144 /* Get the number of seconds since 1970 */
145 rtc_tm_to_time(tm, &secs);
146
147 /*
148 * Convert it to the number of seconds since 01-01-2000 00:00:00, since
149 * we only have a small counter in the RTC.
150 */
151 secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);
152
153 no_mins = secs / 60;
154
155 no_secs = secs % 60;
156 /* Make the seconds count as per the RTC resolution */
157 no_secs = no_secs * COUNTS_PER_SEC;
158
159 buf[4] = no_secs & 0xFF;
160 buf[3] = (no_secs >> 8) & 0xFF;
161
162 buf[2] = no_mins & 0xFF;
163 buf[1] = (no_mins >> 8) & 0xFF;
164 buf[0] = (no_mins >> 16) & 0xFF;
165
166 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {
167 retval = abx500_set_register_interruptible(dev, AB8500_RTC,
168 ab8500_rtc_time_regs[i], buf[i]);
169 if (retval < 0)
170 return retval;
171 }
172
173 /* Request a data write */
174 return abx500_set_register_interruptible(dev, AB8500_RTC,
175 AB8500_RTC_READ_REQ_REG, RTC_WRITE_REQUEST);
176}
177
178static int ab8500_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
179{
180 int retval, i;
181 u8 rtc_ctrl, value;
182 unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
183 unsigned long secs, mins;
184
185 /* Check if the alarm is enabled or not */
186 retval = abx500_get_register_interruptible(dev, AB8500_RTC,
187 AB8500_RTC_STAT_REG, &rtc_ctrl);
188 if (retval < 0)
189 return retval;
190
191 if (rtc_ctrl & RTC_ALARM_ENA)
192 alarm->enabled = 1;
193 else
194 alarm->enabled = 0;
195
196 alarm->pending = 0;
197
198 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) {
199 retval = abx500_get_register_interruptible(dev, AB8500_RTC,
200 ab8500_rtc_alarm_regs[i], &value);
201 if (retval < 0)
202 return retval;
203 buf[i] = value;
204 }
205
206 mins = (buf[0] << 16) | (buf[1] << 8) | (buf[2]);
207 secs = mins * 60;
208
209 /* Add back the initially subtracted number of seconds */
210 secs += get_elapsed_seconds(AB8500_RTC_EPOCH);
211
212 rtc_time_to_tm(secs, &alarm->time);
213
214 return rtc_valid_tm(&alarm->time);
215}
216
217static int ab8500_rtc_irq_enable(struct device *dev, unsigned int enabled)
218{
219 return abx500_mask_and_set_register_interruptible(dev, AB8500_RTC,
220 AB8500_RTC_STAT_REG, RTC_ALARM_ENA,
221 enabled ? RTC_ALARM_ENA : 0);
222}
223
224static int ab8500_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
225{
226 int retval, i;
227 unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
228 unsigned long mins, secs = 0;
229
230 if (alarm->time.tm_year < (AB8500_RTC_EPOCH - 1900)) {
231 dev_dbg(dev, "year should be equal to or greater than %d\n",
232 AB8500_RTC_EPOCH);
233 return -EINVAL;
234 }
235
236 /* Get the number of seconds since 1970 */
237 rtc_tm_to_time(&alarm->time, &secs);
238
239 /*
240 * Convert it to the number of seconds since 01-01-2000 00:00:00, since
241 * we only have a small counter in the RTC.
242 */
243 secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);
244
245 mins = secs / 60;
246
247 buf[2] = mins & 0xFF;
248 buf[1] = (mins >> 8) & 0xFF;
249 buf[0] = (mins >> 16) & 0xFF;
250
251 /* Set the alarm time */
252 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) {
253 retval = abx500_set_register_interruptible(dev, AB8500_RTC,
254 ab8500_rtc_alarm_regs[i], buf[i]);
255 if (retval < 0)
256 return retval;
257 }
258
259 return ab8500_rtc_irq_enable(dev, alarm->enabled);
260}
261
262
263static int ab8500_rtc_set_calibration(struct device *dev, int calibration)
264{
265 int retval;
266 u8 rtccal = 0;
267
268 /*
269 * Check that the calibration value (which is in units of 0.5
270 * parts-per-million) is in the AB8500's range for RtcCalibration
271 * register. -128 (0x80) is not permitted because the AB8500 uses
272 * a sign-bit rather than two's complement, so 0x80 is just another
273 * representation of zero.
274 */
275 if ((calibration < -127) || (calibration > 127)) {
276 dev_err(dev, "RtcCalibration value outside permitted range\n");
277 return -EINVAL;
278 }
279
280 /*
281 * The AB8500 uses sign (in bit7) and magnitude (in bits0-7)
282 * so need to convert to this sort of representation before writing
283 * into RtcCalibration register...
284 */
285 if (calibration >= 0)
286 rtccal = 0x7F & calibration;
287 else
288 rtccal = ~(calibration - 1) | 0x80;
289
290 retval = abx500_set_register_interruptible(dev, AB8500_RTC,
291 AB8500_RTC_CALIB_REG, rtccal);
292
293 return retval;
294}
295
296static int ab8500_rtc_get_calibration(struct device *dev, int *calibration)
297{
298 int retval;
299 u8 rtccal = 0;
300
301 retval = abx500_get_register_interruptible(dev, AB8500_RTC,
302 AB8500_RTC_CALIB_REG, &rtccal);
303 if (retval >= 0) {
304 /*
305 * The AB8500 uses sign (in bit7) and magnitude (in bits0-7)
306 * so need to convert value from RtcCalibration register into
307 * a two's complement signed value...
308 */
309 if (rtccal & 0x80)
310 *calibration = 0 - (rtccal & 0x7F);
311 else
312 *calibration = 0x7F & rtccal;
313 }
314
315 return retval;
316}
317
318static ssize_t ab8500_sysfs_store_rtc_calibration(struct device *dev,
319 struct device_attribute *attr,
320 const char *buf, size_t count)
321{
322 int retval;
323 int calibration = 0;
324
325 if (sscanf(buf, " %i ", &calibration) != 1) {
326 dev_err(dev, "Failed to store RTC calibration attribute\n");
327 return -EINVAL;
328 }
329
330 retval = ab8500_rtc_set_calibration(dev, calibration);
331
332 return retval ? retval : count;
333}
334
335static ssize_t ab8500_sysfs_show_rtc_calibration(struct device *dev,
336 struct device_attribute *attr, char *buf)
337{
338 int retval = 0;
339 int calibration = 0;
340
341 retval = ab8500_rtc_get_calibration(dev, &calibration);
342 if (retval < 0) {
343 dev_err(dev, "Failed to read RTC calibration attribute\n");
344 sprintf(buf, "0\n");
345 return retval;
346 }
347
348 return sprintf(buf, "%d\n", calibration);
349}
350
351static DEVICE_ATTR(rtc_calibration, S_IRUGO | S_IWUSR,
352 ab8500_sysfs_show_rtc_calibration,
353 ab8500_sysfs_store_rtc_calibration);
354
355static int ab8500_sysfs_rtc_register(struct device *dev)
356{
357 return device_create_file(dev, &dev_attr_rtc_calibration);
358}
359
360static void ab8500_sysfs_rtc_unregister(struct device *dev)
361{
362 device_remove_file(dev, &dev_attr_rtc_calibration);
363}
364
365static irqreturn_t rtc_alarm_handler(int irq, void *data)
366{
367 struct rtc_device *rtc = data;
368 unsigned long events = RTC_IRQF | RTC_AF;
369
370 dev_dbg(&rtc->dev, "%s\n", __func__);
371 rtc_update_irq(rtc, 1, events);
372
373 return IRQ_HANDLED;
374}
375
376static const struct rtc_class_ops ab8500_rtc_ops = {
377 .read_time = ab8500_rtc_read_time,
378 .set_time = ab8500_rtc_set_time,
379 .read_alarm = ab8500_rtc_read_alarm,
380 .set_alarm = ab8500_rtc_set_alarm,
381 .alarm_irq_enable = ab8500_rtc_irq_enable,
382};
383
384static int __devinit ab8500_rtc_probe(struct platform_device *pdev)
385{
386 int err;
387 struct rtc_device *rtc;
388 u8 rtc_ctrl;
389 int irq;
390
391 irq = platform_get_irq_byname(pdev, "ALARM");
392 if (irq < 0)
393 return irq;
394
395 /* For RTC supply test */
396 err = abx500_mask_and_set_register_interruptible(&pdev->dev, AB8500_RTC,
397 AB8500_RTC_STAT_REG, RTC_STATUS_DATA, RTC_STATUS_DATA);
398 if (err < 0)
399 return err;
400
401 /* Wait for reset by the PorRtc */
402 usleep_range(1000, 5000);
403
404 err = abx500_get_register_interruptible(&pdev->dev, AB8500_RTC,
405 AB8500_RTC_STAT_REG, &rtc_ctrl);
406 if (err < 0)
407 return err;
408
409 /* Check if the RTC Supply fails */
410 if (!(rtc_ctrl & RTC_STATUS_DATA)) {
411 dev_err(&pdev->dev, "RTC supply failure\n");
412 return -ENODEV;
413 }
414
415 device_init_wakeup(&pdev->dev, true);
416
417 rtc = rtc_device_register("ab8500-rtc", &pdev->dev, &ab8500_rtc_ops,
418 THIS_MODULE);
419 if (IS_ERR(rtc)) {
420 dev_err(&pdev->dev, "Registration failed\n");
421 err = PTR_ERR(rtc);
422 return err;
423 }
424
425 err = request_threaded_irq(irq, NULL, rtc_alarm_handler,
426 IRQF_NO_SUSPEND | IRQF_ONESHOT, "ab8500-rtc", rtc);
427 if (err < 0) {
428 rtc_device_unregister(rtc);
429 return err;
430 }
431
432 platform_set_drvdata(pdev, rtc);
433
434 err = ab8500_sysfs_rtc_register(&pdev->dev);
435 if (err) {
436 dev_err(&pdev->dev, "sysfs RTC failed to register\n");
437 return err;
438 }
439
440 return 0;
441}
442
443static int __devexit ab8500_rtc_remove(struct platform_device *pdev)
444{
445 struct rtc_device *rtc = platform_get_drvdata(pdev);
446 int irq = platform_get_irq_byname(pdev, "ALARM");
447
448 ab8500_sysfs_rtc_unregister(&pdev->dev);
449
450 free_irq(irq, rtc);
451 rtc_device_unregister(rtc);
452 platform_set_drvdata(pdev, NULL);
453
454 return 0;
455}
456
457static const struct of_device_id ab8500_rtc_match[] = {
458 { .compatible = "stericsson,ab8500-rtc", },
459 {}
460};
461
462static struct platform_driver ab8500_rtc_driver = {
463 .driver = {
464 .name = "ab8500-rtc",
465 .owner = THIS_MODULE,
466 .of_match_table = ab8500_rtc_match,
467 },
468 .probe = ab8500_rtc_probe,
469 .remove = __devexit_p(ab8500_rtc_remove),
470};
471
472module_platform_driver(ab8500_rtc_driver);
473
474MODULE_AUTHOR("Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>");
475MODULE_DESCRIPTION("AB8500 RTC Driver");
476MODULE_LICENSE("GPL v2");
1/*
2 * Copyright (C) ST-Ericsson SA 2010
3 *
4 * License terms: GNU General Public License (GPL) version 2
5 * Author: Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>
6 *
7 * RTC clock driver for the RTC part of the AB8500 Power management chip.
8 * Based on RTC clock driver for the AB3100 Analog Baseband Chip by
9 * Linus Walleij <linus.walleij@stericsson.com>
10 */
11
12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/platform_device.h>
16#include <linux/rtc.h>
17#include <linux/mfd/abx500.h>
18#include <linux/mfd/abx500/ab8500.h>
19#include <linux/delay.h>
20#include <linux/of.h>
21
22#define AB8500_RTC_SOFF_STAT_REG 0x00
23#define AB8500_RTC_CC_CONF_REG 0x01
24#define AB8500_RTC_READ_REQ_REG 0x02
25#define AB8500_RTC_WATCH_TSECMID_REG 0x03
26#define AB8500_RTC_WATCH_TSECHI_REG 0x04
27#define AB8500_RTC_WATCH_TMIN_LOW_REG 0x05
28#define AB8500_RTC_WATCH_TMIN_MID_REG 0x06
29#define AB8500_RTC_WATCH_TMIN_HI_REG 0x07
30#define AB8500_RTC_ALRM_MIN_LOW_REG 0x08
31#define AB8500_RTC_ALRM_MIN_MID_REG 0x09
32#define AB8500_RTC_ALRM_MIN_HI_REG 0x0A
33#define AB8500_RTC_STAT_REG 0x0B
34#define AB8500_RTC_BKUP_CHG_REG 0x0C
35#define AB8500_RTC_FORCE_BKUP_REG 0x0D
36#define AB8500_RTC_CALIB_REG 0x0E
37#define AB8500_RTC_SWITCH_STAT_REG 0x0F
38#define AB8540_RTC_ALRM_SEC 0x22
39#define AB8540_RTC_ALRM_MIN_LOW_REG 0x23
40#define AB8540_RTC_ALRM_MIN_MID_REG 0x24
41#define AB8540_RTC_ALRM_MIN_HI_REG 0x25
42
43/* RtcReadRequest bits */
44#define RTC_READ_REQUEST 0x01
45#define RTC_WRITE_REQUEST 0x02
46
47/* RtcCtrl bits */
48#define RTC_ALARM_ENA 0x04
49#define RTC_STATUS_DATA 0x01
50
51#define COUNTS_PER_SEC (0xF000 / 60)
52#define AB8500_RTC_EPOCH 2000
53
54static const u8 ab8500_rtc_time_regs[] = {
55 AB8500_RTC_WATCH_TMIN_HI_REG, AB8500_RTC_WATCH_TMIN_MID_REG,
56 AB8500_RTC_WATCH_TMIN_LOW_REG, AB8500_RTC_WATCH_TSECHI_REG,
57 AB8500_RTC_WATCH_TSECMID_REG
58};
59
60static const u8 ab8500_rtc_alarm_regs[] = {
61 AB8500_RTC_ALRM_MIN_HI_REG, AB8500_RTC_ALRM_MIN_MID_REG,
62 AB8500_RTC_ALRM_MIN_LOW_REG
63};
64
65static const u8 ab8540_rtc_alarm_regs[] = {
66 AB8540_RTC_ALRM_MIN_HI_REG, AB8540_RTC_ALRM_MIN_MID_REG,
67 AB8540_RTC_ALRM_MIN_LOW_REG, AB8540_RTC_ALRM_SEC
68};
69
70/* Calculate the seconds from 1970 to 01-01-2000 00:00:00 */
71static unsigned long get_elapsed_seconds(int year)
72{
73 unsigned long secs;
74 struct rtc_time tm = {
75 .tm_year = year - 1900,
76 .tm_mday = 1,
77 };
78
79 /*
80 * This function calculates secs from 1970 and not from
81 * 1900, even if we supply the offset from year 1900.
82 */
83 rtc_tm_to_time(&tm, &secs);
84 return secs;
85}
86
87static int ab8500_rtc_read_time(struct device *dev, struct rtc_time *tm)
88{
89 unsigned long timeout = jiffies + HZ;
90 int retval, i;
91 unsigned long mins, secs;
92 unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
93 u8 value;
94
95 /* Request a data read */
96 retval = abx500_set_register_interruptible(dev,
97 AB8500_RTC, AB8500_RTC_READ_REQ_REG, RTC_READ_REQUEST);
98 if (retval < 0)
99 return retval;
100
101 /* Wait for some cycles after enabling the rtc read in ab8500 */
102 while (time_before(jiffies, timeout)) {
103 retval = abx500_get_register_interruptible(dev,
104 AB8500_RTC, AB8500_RTC_READ_REQ_REG, &value);
105 if (retval < 0)
106 return retval;
107
108 if (!(value & RTC_READ_REQUEST))
109 break;
110
111 usleep_range(1000, 5000);
112 }
113
114 /* Read the Watchtime registers */
115 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {
116 retval = abx500_get_register_interruptible(dev,
117 AB8500_RTC, ab8500_rtc_time_regs[i], &value);
118 if (retval < 0)
119 return retval;
120 buf[i] = value;
121 }
122
123 mins = (buf[0] << 16) | (buf[1] << 8) | buf[2];
124
125 secs = (buf[3] << 8) | buf[4];
126 secs = secs / COUNTS_PER_SEC;
127 secs = secs + (mins * 60);
128
129 /* Add back the initially subtracted number of seconds */
130 secs += get_elapsed_seconds(AB8500_RTC_EPOCH);
131
132 rtc_time_to_tm(secs, tm);
133 return rtc_valid_tm(tm);
134}
135
136static int ab8500_rtc_set_time(struct device *dev, struct rtc_time *tm)
137{
138 int retval, i;
139 unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
140 unsigned long no_secs, no_mins, secs = 0;
141
142 if (tm->tm_year < (AB8500_RTC_EPOCH - 1900)) {
143 dev_dbg(dev, "year should be equal to or greater than %d\n",
144 AB8500_RTC_EPOCH);
145 return -EINVAL;
146 }
147
148 /* Get the number of seconds since 1970 */
149 rtc_tm_to_time(tm, &secs);
150
151 /*
152 * Convert it to the number of seconds since 01-01-2000 00:00:00, since
153 * we only have a small counter in the RTC.
154 */
155 secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);
156
157 no_mins = secs / 60;
158
159 no_secs = secs % 60;
160 /* Make the seconds count as per the RTC resolution */
161 no_secs = no_secs * COUNTS_PER_SEC;
162
163 buf[4] = no_secs & 0xFF;
164 buf[3] = (no_secs >> 8) & 0xFF;
165
166 buf[2] = no_mins & 0xFF;
167 buf[1] = (no_mins >> 8) & 0xFF;
168 buf[0] = (no_mins >> 16) & 0xFF;
169
170 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {
171 retval = abx500_set_register_interruptible(dev, AB8500_RTC,
172 ab8500_rtc_time_regs[i], buf[i]);
173 if (retval < 0)
174 return retval;
175 }
176
177 /* Request a data write */
178 return abx500_set_register_interruptible(dev, AB8500_RTC,
179 AB8500_RTC_READ_REQ_REG, RTC_WRITE_REQUEST);
180}
181
182static int ab8500_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
183{
184 int retval, i;
185 u8 rtc_ctrl, value;
186 unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
187 unsigned long secs, mins;
188
189 /* Check if the alarm is enabled or not */
190 retval = abx500_get_register_interruptible(dev, AB8500_RTC,
191 AB8500_RTC_STAT_REG, &rtc_ctrl);
192 if (retval < 0)
193 return retval;
194
195 if (rtc_ctrl & RTC_ALARM_ENA)
196 alarm->enabled = 1;
197 else
198 alarm->enabled = 0;
199
200 alarm->pending = 0;
201
202 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) {
203 retval = abx500_get_register_interruptible(dev, AB8500_RTC,
204 ab8500_rtc_alarm_regs[i], &value);
205 if (retval < 0)
206 return retval;
207 buf[i] = value;
208 }
209
210 mins = (buf[0] << 16) | (buf[1] << 8) | (buf[2]);
211 secs = mins * 60;
212
213 /* Add back the initially subtracted number of seconds */
214 secs += get_elapsed_seconds(AB8500_RTC_EPOCH);
215
216 rtc_time_to_tm(secs, &alarm->time);
217
218 return rtc_valid_tm(&alarm->time);
219}
220
221static int ab8500_rtc_irq_enable(struct device *dev, unsigned int enabled)
222{
223 return abx500_mask_and_set_register_interruptible(dev, AB8500_RTC,
224 AB8500_RTC_STAT_REG, RTC_ALARM_ENA,
225 enabled ? RTC_ALARM_ENA : 0);
226}
227
228static int ab8500_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
229{
230 int retval, i;
231 unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
232 unsigned long mins, secs = 0, cursec = 0;
233 struct rtc_time curtm;
234
235 if (alarm->time.tm_year < (AB8500_RTC_EPOCH - 1900)) {
236 dev_dbg(dev, "year should be equal to or greater than %d\n",
237 AB8500_RTC_EPOCH);
238 return -EINVAL;
239 }
240
241 /* Get the number of seconds since 1970 */
242 rtc_tm_to_time(&alarm->time, &secs);
243
244 /*
245 * Check whether alarm is set less than 1min.
246 * Since our RTC doesn't support alarm resolution less than 1min,
247 * return -EINVAL, so UIE EMUL can take it up, incase of UIE_ON
248 */
249 ab8500_rtc_read_time(dev, &curtm); /* Read current time */
250 rtc_tm_to_time(&curtm, &cursec);
251 if ((secs - cursec) < 59) {
252 dev_dbg(dev, "Alarm less than 1 minute not supported\r\n");
253 return -EINVAL;
254 }
255
256 /*
257 * Convert it to the number of seconds since 01-01-2000 00:00:00, since
258 * we only have a small counter in the RTC.
259 */
260 secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);
261
262 mins = secs / 60;
263
264 buf[2] = mins & 0xFF;
265 buf[1] = (mins >> 8) & 0xFF;
266 buf[0] = (mins >> 16) & 0xFF;
267
268 /* Set the alarm time */
269 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) {
270 retval = abx500_set_register_interruptible(dev, AB8500_RTC,
271 ab8500_rtc_alarm_regs[i], buf[i]);
272 if (retval < 0)
273 return retval;
274 }
275
276 return ab8500_rtc_irq_enable(dev, alarm->enabled);
277}
278
279static int ab8540_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
280{
281 int retval, i;
282 unsigned char buf[ARRAY_SIZE(ab8540_rtc_alarm_regs)];
283 unsigned long mins, secs = 0;
284
285 if (alarm->time.tm_year < (AB8500_RTC_EPOCH - 1900)) {
286 dev_dbg(dev, "year should be equal to or greater than %d\n",
287 AB8500_RTC_EPOCH);
288 return -EINVAL;
289 }
290
291 /* Get the number of seconds since 1970 */
292 rtc_tm_to_time(&alarm->time, &secs);
293
294 /*
295 * Convert it to the number of seconds since 01-01-2000 00:00:00
296 */
297 secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);
298 mins = secs / 60;
299
300 buf[3] = secs % 60;
301 buf[2] = mins & 0xFF;
302 buf[1] = (mins >> 8) & 0xFF;
303 buf[0] = (mins >> 16) & 0xFF;
304
305 /* Set the alarm time */
306 for (i = 0; i < ARRAY_SIZE(ab8540_rtc_alarm_regs); i++) {
307 retval = abx500_set_register_interruptible(dev, AB8500_RTC,
308 ab8540_rtc_alarm_regs[i], buf[i]);
309 if (retval < 0)
310 return retval;
311 }
312
313 return ab8500_rtc_irq_enable(dev, alarm->enabled);
314}
315
316static int ab8500_rtc_set_calibration(struct device *dev, int calibration)
317{
318 int retval;
319 u8 rtccal = 0;
320
321 /*
322 * Check that the calibration value (which is in units of 0.5
323 * parts-per-million) is in the AB8500's range for RtcCalibration
324 * register. -128 (0x80) is not permitted because the AB8500 uses
325 * a sign-bit rather than two's complement, so 0x80 is just another
326 * representation of zero.
327 */
328 if ((calibration < -127) || (calibration > 127)) {
329 dev_err(dev, "RtcCalibration value outside permitted range\n");
330 return -EINVAL;
331 }
332
333 /*
334 * The AB8500 uses sign (in bit7) and magnitude (in bits0-7)
335 * so need to convert to this sort of representation before writing
336 * into RtcCalibration register...
337 */
338 if (calibration >= 0)
339 rtccal = 0x7F & calibration;
340 else
341 rtccal = ~(calibration - 1) | 0x80;
342
343 retval = abx500_set_register_interruptible(dev, AB8500_RTC,
344 AB8500_RTC_CALIB_REG, rtccal);
345
346 return retval;
347}
348
349static int ab8500_rtc_get_calibration(struct device *dev, int *calibration)
350{
351 int retval;
352 u8 rtccal = 0;
353
354 retval = abx500_get_register_interruptible(dev, AB8500_RTC,
355 AB8500_RTC_CALIB_REG, &rtccal);
356 if (retval >= 0) {
357 /*
358 * The AB8500 uses sign (in bit7) and magnitude (in bits0-7)
359 * so need to convert value from RtcCalibration register into
360 * a two's complement signed value...
361 */
362 if (rtccal & 0x80)
363 *calibration = 0 - (rtccal & 0x7F);
364 else
365 *calibration = 0x7F & rtccal;
366 }
367
368 return retval;
369}
370
371static ssize_t ab8500_sysfs_store_rtc_calibration(struct device *dev,
372 struct device_attribute *attr,
373 const char *buf, size_t count)
374{
375 int retval;
376 int calibration = 0;
377
378 if (sscanf(buf, " %i ", &calibration) != 1) {
379 dev_err(dev, "Failed to store RTC calibration attribute\n");
380 return -EINVAL;
381 }
382
383 retval = ab8500_rtc_set_calibration(dev, calibration);
384
385 return retval ? retval : count;
386}
387
388static ssize_t ab8500_sysfs_show_rtc_calibration(struct device *dev,
389 struct device_attribute *attr, char *buf)
390{
391 int retval = 0;
392 int calibration = 0;
393
394 retval = ab8500_rtc_get_calibration(dev, &calibration);
395 if (retval < 0) {
396 dev_err(dev, "Failed to read RTC calibration attribute\n");
397 sprintf(buf, "0\n");
398 return retval;
399 }
400
401 return sprintf(buf, "%d\n", calibration);
402}
403
404static DEVICE_ATTR(rtc_calibration, S_IRUGO | S_IWUSR,
405 ab8500_sysfs_show_rtc_calibration,
406 ab8500_sysfs_store_rtc_calibration);
407
408static int ab8500_sysfs_rtc_register(struct device *dev)
409{
410 return device_create_file(dev, &dev_attr_rtc_calibration);
411}
412
413static void ab8500_sysfs_rtc_unregister(struct device *dev)
414{
415 device_remove_file(dev, &dev_attr_rtc_calibration);
416}
417
418static irqreturn_t rtc_alarm_handler(int irq, void *data)
419{
420 struct rtc_device *rtc = data;
421 unsigned long events = RTC_IRQF | RTC_AF;
422
423 dev_dbg(&rtc->dev, "%s\n", __func__);
424 rtc_update_irq(rtc, 1, events);
425
426 return IRQ_HANDLED;
427}
428
429static const struct rtc_class_ops ab8500_rtc_ops = {
430 .read_time = ab8500_rtc_read_time,
431 .set_time = ab8500_rtc_set_time,
432 .read_alarm = ab8500_rtc_read_alarm,
433 .set_alarm = ab8500_rtc_set_alarm,
434 .alarm_irq_enable = ab8500_rtc_irq_enable,
435};
436
437static const struct rtc_class_ops ab8540_rtc_ops = {
438 .read_time = ab8500_rtc_read_time,
439 .set_time = ab8500_rtc_set_time,
440 .read_alarm = ab8500_rtc_read_alarm,
441 .set_alarm = ab8540_rtc_set_alarm,
442 .alarm_irq_enable = ab8500_rtc_irq_enable,
443};
444
445static struct platform_device_id ab85xx_rtc_ids[] = {
446 { "ab8500-rtc", (kernel_ulong_t)&ab8500_rtc_ops, },
447 { "ab8540-rtc", (kernel_ulong_t)&ab8540_rtc_ops, },
448};
449
450static int ab8500_rtc_probe(struct platform_device *pdev)
451{
452 const struct platform_device_id *platid = platform_get_device_id(pdev);
453 int err;
454 struct rtc_device *rtc;
455 u8 rtc_ctrl;
456 int irq;
457
458 irq = platform_get_irq_byname(pdev, "ALARM");
459 if (irq < 0)
460 return irq;
461
462 /* For RTC supply test */
463 err = abx500_mask_and_set_register_interruptible(&pdev->dev, AB8500_RTC,
464 AB8500_RTC_STAT_REG, RTC_STATUS_DATA, RTC_STATUS_DATA);
465 if (err < 0)
466 return err;
467
468 /* Wait for reset by the PorRtc */
469 usleep_range(1000, 5000);
470
471 err = abx500_get_register_interruptible(&pdev->dev, AB8500_RTC,
472 AB8500_RTC_STAT_REG, &rtc_ctrl);
473 if (err < 0)
474 return err;
475
476 /* Check if the RTC Supply fails */
477 if (!(rtc_ctrl & RTC_STATUS_DATA)) {
478 dev_err(&pdev->dev, "RTC supply failure\n");
479 return -ENODEV;
480 }
481
482 device_init_wakeup(&pdev->dev, true);
483
484 rtc = devm_rtc_device_register(&pdev->dev, "ab8500-rtc",
485 (struct rtc_class_ops *)platid->driver_data,
486 THIS_MODULE);
487 if (IS_ERR(rtc)) {
488 dev_err(&pdev->dev, "Registration failed\n");
489 err = PTR_ERR(rtc);
490 return err;
491 }
492
493 err = devm_request_threaded_irq(&pdev->dev, irq, NULL,
494 rtc_alarm_handler, IRQF_NO_SUSPEND | IRQF_ONESHOT,
495 "ab8500-rtc", rtc);
496 if (err < 0)
497 return err;
498
499 platform_set_drvdata(pdev, rtc);
500
501 err = ab8500_sysfs_rtc_register(&pdev->dev);
502 if (err) {
503 dev_err(&pdev->dev, "sysfs RTC failed to register\n");
504 return err;
505 }
506
507 return 0;
508}
509
510static int ab8500_rtc_remove(struct platform_device *pdev)
511{
512 ab8500_sysfs_rtc_unregister(&pdev->dev);
513
514 return 0;
515}
516
517static struct platform_driver ab8500_rtc_driver = {
518 .driver = {
519 .name = "ab8500-rtc",
520 .owner = THIS_MODULE,
521 },
522 .probe = ab8500_rtc_probe,
523 .remove = ab8500_rtc_remove,
524 .id_table = ab85xx_rtc_ids,
525};
526
527module_platform_driver(ab8500_rtc_driver);
528
529MODULE_AUTHOR("Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>");
530MODULE_DESCRIPTION("AB8500 RTC Driver");
531MODULE_LICENSE("GPL v2");