blob: ea33e149d5459055cd3756ad846f9b33c1ffcfb6 [file] [log] [blame]
Thomas Gleixneraf873fc2019-05-28 09:57:21 -07001// SPDX-License-Identifier: GPL-2.0-only
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -07002/*
3 * Copyright (C) ST-Ericsson SA 2010
4 *
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -07005 * 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>
Mattias Wallin47c16972010-09-10 17:47:56 +020017#include <linux/mfd/abx500.h>
Linus Walleijee66e652011-12-02 14:16:33 +010018#include <linux/mfd/abx500/ab8500.h>
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070019#include <linux/delay.h>
Lee Jonesad49fcb2012-07-11 14:02:17 -070020#include <linux/of.h>
Sudeep Holla93a6f912015-09-21 16:46:58 +010021#include <linux/pm_wakeirq.h>
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070022
Mattias Wallin47c16972010-09-10 17:47:56 +020023#define AB8500_RTC_SOFF_STAT_REG 0x00
24#define AB8500_RTC_CC_CONF_REG 0x01
25#define AB8500_RTC_READ_REQ_REG 0x02
26#define AB8500_RTC_WATCH_TSECMID_REG 0x03
27#define AB8500_RTC_WATCH_TSECHI_REG 0x04
28#define AB8500_RTC_WATCH_TMIN_LOW_REG 0x05
29#define AB8500_RTC_WATCH_TMIN_MID_REG 0x06
30#define AB8500_RTC_WATCH_TMIN_HI_REG 0x07
31#define AB8500_RTC_ALRM_MIN_LOW_REG 0x08
32#define AB8500_RTC_ALRM_MIN_MID_REG 0x09
33#define AB8500_RTC_ALRM_MIN_HI_REG 0x0A
34#define AB8500_RTC_STAT_REG 0x0B
35#define AB8500_RTC_BKUP_CHG_REG 0x0C
36#define AB8500_RTC_FORCE_BKUP_REG 0x0D
37#define AB8500_RTC_CALIB_REG 0x0E
38#define AB8500_RTC_SWITCH_STAT_REG 0x0F
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070039
40/* RtcReadRequest bits */
41#define RTC_READ_REQUEST 0x01
42#define RTC_WRITE_REQUEST 0x02
43
44/* RtcCtrl bits */
45#define RTC_ALARM_ENA 0x04
46#define RTC_STATUS_DATA 0x01
47
48#define COUNTS_PER_SEC (0xF000 / 60)
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070049
Mattias Wallin47c16972010-09-10 17:47:56 +020050static const u8 ab8500_rtc_time_regs[] = {
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070051 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
Mattias Wallin47c16972010-09-10 17:47:56 +020056static const u8 ab8500_rtc_alarm_regs[] = {
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070057 AB8500_RTC_ALRM_MIN_HI_REG, AB8500_RTC_ALRM_MIN_MID_REG,
58 AB8500_RTC_ALRM_MIN_LOW_REG
59};
60
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070061static int ab8500_rtc_read_time(struct device *dev, struct rtc_time *tm)
62{
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070063 unsigned long timeout = jiffies + HZ;
64 int retval, i;
65 unsigned long mins, secs;
66 unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
Mattias Wallin47c16972010-09-10 17:47:56 +020067 u8 value;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070068
69 /* Request a data read */
Mattias Wallin47c16972010-09-10 17:47:56 +020070 retval = abx500_set_register_interruptible(dev,
71 AB8500_RTC, AB8500_RTC_READ_REQ_REG, RTC_READ_REQUEST);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070072 if (retval < 0)
73 return retval;
74
Bengt Jonsson064407f12012-07-30 14:41:43 -070075 /* Wait for some cycles after enabling the rtc read in ab8500 */
76 while (time_before(jiffies, timeout)) {
77 retval = abx500_get_register_interruptible(dev,
78 AB8500_RTC, AB8500_RTC_READ_REQ_REG, &value);
79 if (retval < 0)
80 return retval;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070081
Bengt Jonsson064407f12012-07-30 14:41:43 -070082 if (!(value & RTC_READ_REQUEST))
83 break;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070084
Bengt Jonsson064407f12012-07-30 14:41:43 -070085 usleep_range(1000, 5000);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070086 }
87
88 /* Read the Watchtime registers */
89 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {
Mattias Wallin47c16972010-09-10 17:47:56 +020090 retval = abx500_get_register_interruptible(dev,
91 AB8500_RTC, ab8500_rtc_time_regs[i], &value);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070092 if (retval < 0)
93 return retval;
Mattias Wallin47c16972010-09-10 17:47:56 +020094 buf[i] = value;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -070095 }
96
97 mins = (buf[0] << 16) | (buf[1] << 8) | buf[2];
98
99 secs = (buf[3] << 8) | buf[4];
100 secs = secs / COUNTS_PER_SEC;
101 secs = secs + (mins * 60);
102
Alexandre Bellonia5965a32020-03-06 02:01:01 +0100103 rtc_time64_to_tm(secs, tm);
Alexandre Belloniab626702018-02-19 16:23:55 +0100104 return 0;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700105}
106
107static int ab8500_rtc_set_time(struct device *dev, struct rtc_time *tm)
108{
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700109 int retval, i;
110 unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
111 unsigned long no_secs, no_mins, secs = 0;
112
Alexandre Bellonia5965a32020-03-06 02:01:01 +0100113 secs = rtc_tm_to_time64(tm);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700114
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700115 no_mins = secs / 60;
116
117 no_secs = secs % 60;
118 /* Make the seconds count as per the RTC resolution */
119 no_secs = no_secs * COUNTS_PER_SEC;
120
121 buf[4] = no_secs & 0xFF;
122 buf[3] = (no_secs >> 8) & 0xFF;
123
124 buf[2] = no_mins & 0xFF;
125 buf[1] = (no_mins >> 8) & 0xFF;
126 buf[0] = (no_mins >> 16) & 0xFF;
127
128 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {
Mattias Wallin47c16972010-09-10 17:47:56 +0200129 retval = abx500_set_register_interruptible(dev, AB8500_RTC,
130 ab8500_rtc_time_regs[i], buf[i]);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700131 if (retval < 0)
132 return retval;
133 }
134
135 /* Request a data write */
Mattias Wallin47c16972010-09-10 17:47:56 +0200136 return abx500_set_register_interruptible(dev, AB8500_RTC,
137 AB8500_RTC_READ_REQ_REG, RTC_WRITE_REQUEST);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700138}
139
140static int ab8500_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
141{
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700142 int retval, i;
Mattias Wallin47c16972010-09-10 17:47:56 +0200143 u8 rtc_ctrl, value;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700144 unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
145 unsigned long secs, mins;
146
147 /* Check if the alarm is enabled or not */
Mattias Wallin47c16972010-09-10 17:47:56 +0200148 retval = abx500_get_register_interruptible(dev, AB8500_RTC,
149 AB8500_RTC_STAT_REG, &rtc_ctrl);
150 if (retval < 0)
151 return retval;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700152
153 if (rtc_ctrl & RTC_ALARM_ENA)
154 alarm->enabled = 1;
155 else
156 alarm->enabled = 0;
157
158 alarm->pending = 0;
159
160 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) {
Mattias Wallin47c16972010-09-10 17:47:56 +0200161 retval = abx500_get_register_interruptible(dev, AB8500_RTC,
162 ab8500_rtc_alarm_regs[i], &value);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700163 if (retval < 0)
164 return retval;
Mattias Wallin47c16972010-09-10 17:47:56 +0200165 buf[i] = value;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700166 }
167
168 mins = (buf[0] << 16) | (buf[1] << 8) | (buf[2]);
169 secs = mins * 60;
170
Alexandre Bellonia5965a32020-03-06 02:01:01 +0100171 rtc_time64_to_tm(secs, &alarm->time);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700172
Alexandre Belloni9a90a5b2018-09-24 16:49:02 +0200173 return 0;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700174}
175
176static int ab8500_rtc_irq_enable(struct device *dev, unsigned int enabled)
177{
Mattias Wallin47c16972010-09-10 17:47:56 +0200178 return abx500_mask_and_set_register_interruptible(dev, AB8500_RTC,
179 AB8500_RTC_STAT_REG, RTC_ALARM_ENA,
180 enabled ? RTC_ALARM_ENA : 0);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700181}
182
183static int ab8500_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
184{
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700185 int retval, i;
186 unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
Alexandre Bellonia5f82802021-11-07 23:54:51 +0100187 unsigned long mins;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700188
Alexandre Bellonia5f82802021-11-07 23:54:51 +0100189 mins = (unsigned long)rtc_tm_to_time64(&alarm->time) / 60;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700190
191 buf[2] = mins & 0xFF;
192 buf[1] = (mins >> 8) & 0xFF;
193 buf[0] = (mins >> 16) & 0xFF;
194
195 /* Set the alarm time */
196 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) {
Mattias Wallin47c16972010-09-10 17:47:56 +0200197 retval = abx500_set_register_interruptible(dev, AB8500_RTC,
198 ab8500_rtc_alarm_regs[i], buf[i]);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700199 if (retval < 0)
200 return retval;
201 }
202
203 return ab8500_rtc_irq_enable(dev, alarm->enabled);
204}
205
Mark Godfreydda367a2012-01-10 15:10:42 -0800206static int ab8500_rtc_set_calibration(struct device *dev, int calibration)
207{
208 int retval;
209 u8 rtccal = 0;
210
211 /*
212 * Check that the calibration value (which is in units of 0.5
213 * parts-per-million) is in the AB8500's range for RtcCalibration
214 * register. -128 (0x80) is not permitted because the AB8500 uses
215 * a sign-bit rather than two's complement, so 0x80 is just another
216 * representation of zero.
217 */
218 if ((calibration < -127) || (calibration > 127)) {
219 dev_err(dev, "RtcCalibration value outside permitted range\n");
220 return -EINVAL;
221 }
222
223 /*
224 * The AB8500 uses sign (in bit7) and magnitude (in bits0-7)
225 * so need to convert to this sort of representation before writing
226 * into RtcCalibration register...
227 */
228 if (calibration >= 0)
229 rtccal = 0x7F & calibration;
230 else
231 rtccal = ~(calibration - 1) | 0x80;
232
233 retval = abx500_set_register_interruptible(dev, AB8500_RTC,
234 AB8500_RTC_CALIB_REG, rtccal);
235
236 return retval;
237}
238
239static int ab8500_rtc_get_calibration(struct device *dev, int *calibration)
240{
241 int retval;
242 u8 rtccal = 0;
243
244 retval = abx500_get_register_interruptible(dev, AB8500_RTC,
245 AB8500_RTC_CALIB_REG, &rtccal);
246 if (retval >= 0) {
247 /*
248 * The AB8500 uses sign (in bit7) and magnitude (in bits0-7)
249 * so need to convert value from RtcCalibration register into
250 * a two's complement signed value...
251 */
252 if (rtccal & 0x80)
253 *calibration = 0 - (rtccal & 0x7F);
254 else
255 *calibration = 0x7F & rtccal;
256 }
257
258 return retval;
259}
260
261static ssize_t ab8500_sysfs_store_rtc_calibration(struct device *dev,
262 struct device_attribute *attr,
263 const char *buf, size_t count)
264{
265 int retval;
266 int calibration = 0;
267
268 if (sscanf(buf, " %i ", &calibration) != 1) {
269 dev_err(dev, "Failed to store RTC calibration attribute\n");
270 return -EINVAL;
271 }
272
273 retval = ab8500_rtc_set_calibration(dev, calibration);
274
275 return retval ? retval : count;
276}
277
278static ssize_t ab8500_sysfs_show_rtc_calibration(struct device *dev,
279 struct device_attribute *attr, char *buf)
280{
281 int retval = 0;
282 int calibration = 0;
283
284 retval = ab8500_rtc_get_calibration(dev, &calibration);
285 if (retval < 0) {
286 dev_err(dev, "Failed to read RTC calibration attribute\n");
287 sprintf(buf, "0\n");
288 return retval;
289 }
290
291 return sprintf(buf, "%d\n", calibration);
292}
293
294static DEVICE_ATTR(rtc_calibration, S_IRUGO | S_IWUSR,
295 ab8500_sysfs_show_rtc_calibration,
296 ab8500_sysfs_store_rtc_calibration);
297
Alexandre Bellonib56295d2018-09-24 16:49:00 +0200298static struct attribute *ab8500_rtc_attrs[] = {
299 &dev_attr_rtc_calibration.attr,
300 NULL
301};
Mark Godfreydda367a2012-01-10 15:10:42 -0800302
Alexandre Bellonib56295d2018-09-24 16:49:00 +0200303static const struct attribute_group ab8500_rtc_sysfs_files = {
304 .attrs = ab8500_rtc_attrs,
305};
Mark Godfreydda367a2012-01-10 15:10:42 -0800306
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700307static irqreturn_t rtc_alarm_handler(int irq, void *data)
308{
309 struct rtc_device *rtc = data;
310 unsigned long events = RTC_IRQF | RTC_AF;
311
312 dev_dbg(&rtc->dev, "%s\n", __func__);
313 rtc_update_irq(rtc, 1, events);
314
315 return IRQ_HANDLED;
316}
317
318static const struct rtc_class_ops ab8500_rtc_ops = {
319 .read_time = ab8500_rtc_read_time,
320 .set_time = ab8500_rtc_set_time,
321 .read_alarm = ab8500_rtc_read_alarm,
322 .set_alarm = ab8500_rtc_set_alarm,
323 .alarm_irq_enable = ab8500_rtc_irq_enable,
324};
325
Krzysztof Kozlowski9a72f412015-05-02 00:44:35 +0900326static const struct platform_device_id ab85xx_rtc_ids[] = {
Alexandre Torgue25d053c2013-07-03 15:07:45 -0700327 { "ab8500-rtc", (kernel_ulong_t)&ab8500_rtc_ops, },
Fabio Estevam8a67e932015-09-04 08:58:05 -0300328 { /* sentinel */ }
Alexandre Torgue25d053c2013-07-03 15:07:45 -0700329};
Javier Martinez Canillas63074cc2015-08-27 12:34:32 +0200330MODULE_DEVICE_TABLE(platform, ab85xx_rtc_ids);
Alexandre Torgue25d053c2013-07-03 15:07:45 -0700331
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -0800332static int ab8500_rtc_probe(struct platform_device *pdev)
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700333{
Alexandre Torgue25d053c2013-07-03 15:07:45 -0700334 const struct platform_device_id *platid = platform_get_device_id(pdev);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700335 int err;
336 struct rtc_device *rtc;
Mattias Wallin47c16972010-09-10 17:47:56 +0200337 u8 rtc_ctrl;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700338 int irq;
339
340 irq = platform_get_irq_byname(pdev, "ALARM");
341 if (irq < 0)
342 return irq;
343
344 /* For RTC supply test */
Mattias Wallin47c16972010-09-10 17:47:56 +0200345 err = abx500_mask_and_set_register_interruptible(&pdev->dev, AB8500_RTC,
346 AB8500_RTC_STAT_REG, RTC_STATUS_DATA, RTC_STATUS_DATA);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700347 if (err < 0)
348 return err;
349
350 /* Wait for reset by the PorRtc */
Linus Walleij012e52e2012-01-10 15:10:41 -0800351 usleep_range(1000, 5000);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700352
Mattias Wallin47c16972010-09-10 17:47:56 +0200353 err = abx500_get_register_interruptible(&pdev->dev, AB8500_RTC,
354 AB8500_RTC_STAT_REG, &rtc_ctrl);
355 if (err < 0)
356 return err;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700357
358 /* Check if the RTC Supply fails */
359 if (!(rtc_ctrl & RTC_STATUS_DATA)) {
360 dev_err(&pdev->dev, "RTC supply failure\n");
361 return -ENODEV;
362 }
363
Andrew Lynnb62581e2012-01-10 15:10:38 -0800364 device_init_wakeup(&pdev->dev, true);
365
Alexandre Bellonib56295d2018-09-24 16:49:00 +0200366 rtc = devm_rtc_allocate_device(&pdev->dev);
367 if (IS_ERR(rtc))
368 return PTR_ERR(rtc);
369
370 rtc->ops = (struct rtc_class_ops *)platid->driver_data;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700371
Jingoo Hanfa11f7e2013-04-29 16:20:34 -0700372 err = devm_request_threaded_irq(&pdev->dev, irq, NULL,
Sudeep Holla93a6f912015-09-21 16:46:58 +0100373 rtc_alarm_handler, IRQF_ONESHOT,
Jingoo Hanfa11f7e2013-04-29 16:20:34 -0700374 "ab8500-rtc", rtc);
375 if (err < 0)
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700376 return err;
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700377
Sudeep Holla93a6f912015-09-21 16:46:58 +0100378 dev_pm_set_wake_irq(&pdev->dev, irq);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700379 platform_set_drvdata(pdev, rtc);
380
Alexandre Bellonia5f82802021-11-07 23:54:51 +0100381 set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->features);
382 clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->features);
Xunlei Pangc594d672014-12-10 15:54:23 -0800383
Alexandre Belloni38ab97a2018-09-24 16:49:01 +0200384 rtc->range_max = (1ULL << 24) * 60 - 1; // 24-bit minutes + 59 secs
385 rtc->start_secs = RTC_TIMESTAMP_BEGIN_2000;
386 rtc->set_start_time = true;
387
Alexandre Bellonib56295d2018-09-24 16:49:00 +0200388 err = rtc_add_group(rtc, &ab8500_rtc_sysfs_files);
389 if (err)
390 return err;
391
Bartosz Golaszewskifdcfd852020-11-09 17:34:08 +0100392 return devm_rtc_register_device(rtc);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700393}
394
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -0800395static int ab8500_rtc_remove(struct platform_device *pdev)
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700396{
Sudeep Holla93a6f912015-09-21 16:46:58 +0100397 dev_pm_clear_wake_irq(&pdev->dev);
398 device_init_wakeup(&pdev->dev, false);
Mark Godfreydda367a2012-01-10 15:10:42 -0800399
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700400 return 0;
401}
402
403static struct platform_driver ab8500_rtc_driver = {
404 .driver = {
405 .name = "ab8500-rtc",
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700406 },
407 .probe = ab8500_rtc_probe,
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -0800408 .remove = ab8500_rtc_remove,
Alexandre Torgue25d053c2013-07-03 15:07:45 -0700409 .id_table = ab85xx_rtc_ids,
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700410};
411
Axel Lin0c4eae62012-01-10 15:10:48 -0800412module_platform_driver(ab8500_rtc_driver);
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700413
Virupax Sadashivpetimath0af62f42010-05-26 14:42:14 -0700414MODULE_AUTHOR("Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>");
415MODULE_DESCRIPTION("AB8500 RTC Driver");
416MODULE_LICENSE("GPL v2");