GNU Linux-libre 4.4.289-gnu1
[releases.git] / drivers / rtc / rtc-da9063.c
1 /* rtc-da9063.c - Real time clock device driver for DA9063
2  * Copyright (C) 2013-2015  Dialog Semiconductor Ltd.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version 2
7  * of the License, or (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  */
14
15 #include <linux/delay.h>
16 #include <linux/init.h>
17 #include <linux/interrupt.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/of.h>
21 #include <linux/platform_device.h>
22 #include <linux/regmap.h>
23 #include <linux/rtc.h>
24 #include <linux/slab.h>
25
26 #include <linux/mfd/da9062/registers.h>
27 #include <linux/mfd/da9063/registers.h>
28 #include <linux/mfd/da9063/core.h>
29
30 #define YEARS_TO_DA9063(year)           ((year) - 100)
31 #define MONTHS_TO_DA9063(month)         ((month) + 1)
32 #define YEARS_FROM_DA9063(year)         ((year) + 100)
33 #define MONTHS_FROM_DA9063(month)       ((month) - 1)
34
35 enum {
36         RTC_SEC = 0,
37         RTC_MIN = 1,
38         RTC_HOUR = 2,
39         RTC_DAY = 3,
40         RTC_MONTH = 4,
41         RTC_YEAR = 5,
42         RTC_DATA_LEN
43 };
44
45 struct da9063_compatible_rtc_regmap {
46         /* REGS */
47         int rtc_enable_reg;
48         int rtc_enable_32k_crystal_reg;
49         int rtc_alarm_secs_reg;
50         int rtc_alarm_year_reg;
51         int rtc_count_secs_reg;
52         int rtc_count_year_reg;
53         int rtc_event_reg;
54         /* MASKS */
55         int rtc_enable_mask;
56         int rtc_crystal_mask;
57         int rtc_event_alarm_mask;
58         int rtc_alarm_on_mask;
59         int rtc_alarm_status_mask;
60         int rtc_tick_on_mask;
61         int rtc_ready_to_read_mask;
62         int rtc_count_sec_mask;
63         int rtc_count_min_mask;
64         int rtc_count_hour_mask;
65         int rtc_count_day_mask;
66         int rtc_count_month_mask;
67         int rtc_count_year_mask;
68         /* ALARM CONFIG */
69         int rtc_data_start;
70         int rtc_alarm_len;
71 };
72
73 struct da9063_compatible_rtc {
74         struct rtc_device *rtc_dev;
75         struct rtc_time alarm_time;
76         struct regmap *regmap;
77         const struct da9063_compatible_rtc_regmap *config;
78         bool rtc_sync;
79 };
80
81 static const struct da9063_compatible_rtc_regmap da9063_ad_regs = {
82         /* REGS */
83         .rtc_enable_reg             = DA9063_REG_CONTROL_E,
84         .rtc_alarm_secs_reg         = DA9063_AD_REG_ALARM_MI,
85         .rtc_alarm_year_reg         = DA9063_AD_REG_ALARM_Y,
86         .rtc_count_secs_reg         = DA9063_REG_COUNT_S,
87         .rtc_count_year_reg         = DA9063_REG_COUNT_Y,
88         .rtc_event_reg              = DA9063_REG_EVENT_A,
89         /* MASKS */
90         .rtc_enable_mask            = DA9063_RTC_EN,
91         .rtc_crystal_mask           = DA9063_CRYSTAL,
92         .rtc_enable_32k_crystal_reg = DA9063_REG_EN_32K,
93         .rtc_event_alarm_mask       = DA9063_E_ALARM,
94         .rtc_alarm_on_mask          = DA9063_ALARM_ON,
95         .rtc_alarm_status_mask      = DA9063_ALARM_STATUS_ALARM |
96                                       DA9063_ALARM_STATUS_TICK,
97         .rtc_tick_on_mask           = DA9063_TICK_ON,
98         .rtc_ready_to_read_mask     = DA9063_RTC_READ,
99         .rtc_count_sec_mask         = DA9063_COUNT_SEC_MASK,
100         .rtc_count_min_mask         = DA9063_COUNT_MIN_MASK,
101         .rtc_count_hour_mask        = DA9063_COUNT_HOUR_MASK,
102         .rtc_count_day_mask         = DA9063_COUNT_DAY_MASK,
103         .rtc_count_month_mask       = DA9063_COUNT_MONTH_MASK,
104         .rtc_count_year_mask        = DA9063_COUNT_YEAR_MASK,
105         /* ALARM CONFIG */
106         .rtc_data_start             = RTC_MIN,
107         .rtc_alarm_len              = RTC_DATA_LEN - 1,
108 };
109
110 static const struct da9063_compatible_rtc_regmap da9063_bb_regs = {
111         /* REGS */
112         .rtc_enable_reg             = DA9063_REG_CONTROL_E,
113         .rtc_alarm_secs_reg         = DA9063_BB_REG_ALARM_S,
114         .rtc_alarm_year_reg         = DA9063_BB_REG_ALARM_Y,
115         .rtc_count_secs_reg         = DA9063_REG_COUNT_S,
116         .rtc_count_year_reg         = DA9063_REG_COUNT_Y,
117         .rtc_event_reg              = DA9063_REG_EVENT_A,
118         /* MASKS */
119         .rtc_enable_mask            = DA9063_RTC_EN,
120         .rtc_crystal_mask           = DA9063_CRYSTAL,
121         .rtc_enable_32k_crystal_reg = DA9063_REG_EN_32K,
122         .rtc_event_alarm_mask       = DA9063_E_ALARM,
123         .rtc_alarm_on_mask          = DA9063_ALARM_ON,
124         .rtc_alarm_status_mask      = DA9063_ALARM_STATUS_ALARM |
125                                       DA9063_ALARM_STATUS_TICK,
126         .rtc_tick_on_mask           = DA9063_TICK_ON,
127         .rtc_ready_to_read_mask     = DA9063_RTC_READ,
128         .rtc_count_sec_mask         = DA9063_COUNT_SEC_MASK,
129         .rtc_count_min_mask         = DA9063_COUNT_MIN_MASK,
130         .rtc_count_hour_mask        = DA9063_COUNT_HOUR_MASK,
131         .rtc_count_day_mask         = DA9063_COUNT_DAY_MASK,
132         .rtc_count_month_mask       = DA9063_COUNT_MONTH_MASK,
133         .rtc_count_year_mask        = DA9063_COUNT_YEAR_MASK,
134         /* ALARM CONFIG */
135         .rtc_data_start             = RTC_SEC,
136         .rtc_alarm_len              = RTC_DATA_LEN,
137 };
138
139 static const struct da9063_compatible_rtc_regmap da9062_aa_regs = {
140         /* REGS */
141         .rtc_enable_reg             = DA9062AA_CONTROL_E,
142         .rtc_alarm_secs_reg         = DA9062AA_ALARM_S,
143         .rtc_alarm_year_reg         = DA9062AA_ALARM_Y,
144         .rtc_count_secs_reg         = DA9062AA_COUNT_S,
145         .rtc_count_year_reg         = DA9062AA_COUNT_Y,
146         .rtc_event_reg              = DA9062AA_EVENT_A,
147         /* MASKS */
148         .rtc_enable_mask            = DA9062AA_RTC_EN_MASK,
149         .rtc_crystal_mask           = DA9062AA_CRYSTAL_MASK,
150         .rtc_enable_32k_crystal_reg = DA9062AA_EN_32K,
151         .rtc_event_alarm_mask       = DA9062AA_M_ALARM_MASK,
152         .rtc_alarm_on_mask          = DA9062AA_ALARM_ON_MASK,
153         .rtc_alarm_status_mask      = (0x02 << 6),
154         .rtc_tick_on_mask           = DA9062AA_TICK_ON_MASK,
155         .rtc_ready_to_read_mask     = DA9062AA_RTC_READ_MASK,
156         .rtc_count_sec_mask         = DA9062AA_COUNT_SEC_MASK,
157         .rtc_count_min_mask         = DA9062AA_COUNT_MIN_MASK,
158         .rtc_count_hour_mask        = DA9062AA_COUNT_HOUR_MASK,
159         .rtc_count_day_mask         = DA9062AA_COUNT_DAY_MASK,
160         .rtc_count_month_mask       = DA9062AA_COUNT_MONTH_MASK,
161         .rtc_count_year_mask        = DA9062AA_COUNT_YEAR_MASK,
162         /* ALARM CONFIG */
163         .rtc_data_start             = RTC_SEC,
164         .rtc_alarm_len              = RTC_DATA_LEN,
165 };
166
167 static const struct of_device_id da9063_compatible_reg_id_table[] = {
168         { .compatible = "dlg,da9063-rtc", .data = &da9063_bb_regs },
169         { .compatible = "dlg,da9062-rtc", .data = &da9062_aa_regs },
170         { },
171 };
172 MODULE_DEVICE_TABLE(of, da9063_compatible_reg_id_table);
173
174 static void da9063_data_to_tm(u8 *data, struct rtc_time *tm,
175                               struct da9063_compatible_rtc *rtc)
176 {
177         const struct da9063_compatible_rtc_regmap *config = rtc->config;
178
179         tm->tm_sec  = data[RTC_SEC]  & config->rtc_count_sec_mask;
180         tm->tm_min  = data[RTC_MIN]  & config->rtc_count_min_mask;
181         tm->tm_hour = data[RTC_HOUR] & config->rtc_count_hour_mask;
182         tm->tm_mday = data[RTC_DAY]  & config->rtc_count_day_mask;
183         tm->tm_mon  = MONTHS_FROM_DA9063(data[RTC_MONTH] &
184                                          config->rtc_count_month_mask);
185         tm->tm_year = YEARS_FROM_DA9063(data[RTC_YEAR] &
186                                         config->rtc_count_year_mask);
187 }
188
189 static void da9063_tm_to_data(struct rtc_time *tm, u8 *data,
190                               struct da9063_compatible_rtc *rtc)
191 {
192         const struct da9063_compatible_rtc_regmap *config = rtc->config;
193
194         data[RTC_SEC] &= ~config->rtc_count_sec_mask;
195         data[RTC_SEC] |= tm->tm_sec & config->rtc_count_sec_mask;
196
197         data[RTC_MIN] &= ~config->rtc_count_min_mask;
198         data[RTC_MIN] |= tm->tm_min & config->rtc_count_min_mask;
199
200         data[RTC_HOUR] &= ~config->rtc_count_hour_mask;
201         data[RTC_HOUR] |= tm->tm_hour & config->rtc_count_hour_mask;
202
203         data[RTC_DAY] &= ~config->rtc_count_day_mask;
204         data[RTC_DAY] |= tm->tm_mday & config->rtc_count_day_mask;
205
206         data[RTC_MONTH] &= ~config->rtc_count_month_mask;
207         data[RTC_MONTH] |= MONTHS_TO_DA9063(tm->tm_mon) &
208                                 config->rtc_count_month_mask;
209
210         data[RTC_YEAR] &= ~config->rtc_count_year_mask;
211         data[RTC_YEAR] |= YEARS_TO_DA9063(tm->tm_year) &
212                                 config->rtc_count_year_mask;
213 }
214
215 static int da9063_rtc_stop_alarm(struct device *dev)
216 {
217         struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
218         const struct da9063_compatible_rtc_regmap *config = rtc->config;
219
220         return regmap_update_bits(rtc->regmap,
221                                   config->rtc_alarm_year_reg,
222                                   config->rtc_alarm_on_mask,
223                                   0);
224 }
225
226 static int da9063_rtc_start_alarm(struct device *dev)
227 {
228         struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
229         const struct da9063_compatible_rtc_regmap *config = rtc->config;
230
231         return regmap_update_bits(rtc->regmap,
232                                   config->rtc_alarm_year_reg,
233                                   config->rtc_alarm_on_mask,
234                                   config->rtc_alarm_on_mask);
235 }
236
237 static int da9063_rtc_read_time(struct device *dev, struct rtc_time *tm)
238 {
239         struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
240         const struct da9063_compatible_rtc_regmap *config = rtc->config;
241         unsigned long tm_secs;
242         unsigned long al_secs;
243         u8 data[RTC_DATA_LEN];
244         int ret;
245
246         ret = regmap_bulk_read(rtc->regmap,
247                                config->rtc_count_secs_reg,
248                                data, RTC_DATA_LEN);
249         if (ret < 0) {
250                 dev_err(dev, "Failed to read RTC time data: %d\n", ret);
251                 return ret;
252         }
253
254         if (!(data[RTC_SEC] & config->rtc_ready_to_read_mask)) {
255                 dev_dbg(dev, "RTC not yet ready to be read by the host\n");
256                 return -EINVAL;
257         }
258
259         da9063_data_to_tm(data, tm, rtc);
260
261         rtc_tm_to_time(tm, &tm_secs);
262         rtc_tm_to_time(&rtc->alarm_time, &al_secs);
263
264         /* handle the rtc synchronisation delay */
265         if (rtc->rtc_sync == true && al_secs - tm_secs == 1)
266                 memcpy(tm, &rtc->alarm_time, sizeof(struct rtc_time));
267         else
268                 rtc->rtc_sync = false;
269
270         return rtc_valid_tm(tm);
271 }
272
273 static int da9063_rtc_set_time(struct device *dev, struct rtc_time *tm)
274 {
275         struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
276         const struct da9063_compatible_rtc_regmap *config = rtc->config;
277         u8 data[RTC_DATA_LEN];
278         int ret;
279
280         da9063_tm_to_data(tm, data, rtc);
281         ret = regmap_bulk_write(rtc->regmap,
282                                 config->rtc_count_secs_reg,
283                                 data, RTC_DATA_LEN);
284         if (ret < 0)
285                 dev_err(dev, "Failed to set RTC time data: %d\n", ret);
286
287         return ret;
288 }
289
290 static int da9063_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
291 {
292         struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
293         const struct da9063_compatible_rtc_regmap *config = rtc->config;
294         u8 data[RTC_DATA_LEN];
295         int ret;
296         unsigned int val;
297
298         data[RTC_SEC] = 0;
299         ret = regmap_bulk_read(rtc->regmap,
300                                config->rtc_alarm_secs_reg,
301                                &data[config->rtc_data_start],
302                                config->rtc_alarm_len);
303         if (ret < 0)
304                 return ret;
305
306         da9063_data_to_tm(data, &alrm->time, rtc);
307
308         alrm->enabled = !!(data[RTC_YEAR] & config->rtc_alarm_on_mask);
309
310         ret = regmap_read(rtc->regmap,
311                           config->rtc_event_reg,
312                           &val);
313         if (ret < 0)
314                 return ret;
315
316         if (val & config->rtc_event_alarm_mask)
317                 alrm->pending = 1;
318         else
319                 alrm->pending = 0;
320
321         return 0;
322 }
323
324 static int da9063_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
325 {
326         struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
327         const struct da9063_compatible_rtc_regmap *config = rtc->config;
328         u8 data[RTC_DATA_LEN];
329         int ret;
330
331         da9063_tm_to_data(&alrm->time, data, rtc);
332
333         ret = da9063_rtc_stop_alarm(dev);
334         if (ret < 0) {
335                 dev_err(dev, "Failed to stop alarm: %d\n", ret);
336                 return ret;
337         }
338
339         ret = regmap_bulk_write(rtc->regmap,
340                                 config->rtc_alarm_secs_reg,
341                                 &data[config->rtc_data_start],
342                                 config->rtc_alarm_len);
343         if (ret < 0) {
344                 dev_err(dev, "Failed to write alarm: %d\n", ret);
345                 return ret;
346         }
347
348         da9063_data_to_tm(data, &rtc->alarm_time, rtc);
349
350         if (alrm->enabled) {
351                 ret = da9063_rtc_start_alarm(dev);
352                 if (ret < 0) {
353                         dev_err(dev, "Failed to start alarm: %d\n", ret);
354                         return ret;
355                 }
356         }
357
358         return ret;
359 }
360
361 static int da9063_rtc_alarm_irq_enable(struct device *dev,
362                                        unsigned int enabled)
363 {
364         if (enabled)
365                 return da9063_rtc_start_alarm(dev);
366         else
367                 return da9063_rtc_stop_alarm(dev);
368 }
369
370 static irqreturn_t da9063_alarm_event(int irq, void *data)
371 {
372         struct da9063_compatible_rtc *rtc = data;
373         const struct da9063_compatible_rtc_regmap *config = rtc->config;
374
375         regmap_update_bits(rtc->regmap,
376                            config->rtc_alarm_year_reg,
377                            config->rtc_alarm_on_mask,
378                            0);
379
380         rtc->rtc_sync = true;
381         rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF);
382
383         return IRQ_HANDLED;
384 }
385
386 static const struct rtc_class_ops da9063_rtc_ops = {
387         .read_time = da9063_rtc_read_time,
388         .set_time = da9063_rtc_set_time,
389         .read_alarm = da9063_rtc_read_alarm,
390         .set_alarm = da9063_rtc_set_alarm,
391         .alarm_irq_enable = da9063_rtc_alarm_irq_enable,
392 };
393
394 static int da9063_rtc_probe(struct platform_device *pdev)
395 {
396         struct da9063_compatible_rtc *rtc;
397         const struct da9063_compatible_rtc_regmap *config;
398         const struct of_device_id *match;
399         int irq_alarm;
400         u8 data[RTC_DATA_LEN];
401         int ret;
402
403         if (!pdev->dev.of_node)
404                 return -ENXIO;
405
406         match = of_match_node(da9063_compatible_reg_id_table,
407                               pdev->dev.of_node);
408
409         rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
410         if (!rtc)
411                 return -ENOMEM;
412
413         rtc->config = match->data;
414         if (of_device_is_compatible(pdev->dev.of_node, "dlg,da9063-rtc")) {
415                 struct da9063 *chip = dev_get_drvdata(pdev->dev.parent);
416
417                 if (chip->variant_code == PMIC_DA9063_AD)
418                         rtc->config = &da9063_ad_regs;
419         }
420
421         rtc->regmap = dev_get_regmap(pdev->dev.parent, NULL);
422         if (!rtc->regmap) {
423                 dev_warn(&pdev->dev, "Parent regmap unavailable.\n");
424                 return -ENXIO;
425         }
426
427         config = rtc->config;
428         ret = regmap_update_bits(rtc->regmap,
429                                  config->rtc_enable_reg,
430                                  config->rtc_enable_mask,
431                                  config->rtc_enable_mask);
432         if (ret < 0) {
433                 dev_err(&pdev->dev, "Failed to enable RTC\n");
434                 return ret;
435         }
436
437         ret = regmap_update_bits(rtc->regmap,
438                                  config->rtc_enable_32k_crystal_reg,
439                                  config->rtc_crystal_mask,
440                                  config->rtc_crystal_mask);
441         if (ret < 0) {
442                 dev_err(&pdev->dev, "Failed to run 32kHz oscillator\n");
443                 return ret;
444         }
445
446         ret = regmap_update_bits(rtc->regmap,
447                                  config->rtc_alarm_secs_reg,
448                                  config->rtc_alarm_status_mask,
449                                  0);
450         if (ret < 0) {
451                 dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
452                 return ret;
453         }
454
455         ret = regmap_update_bits(rtc->regmap,
456                                  config->rtc_alarm_secs_reg,
457                                  DA9063_ALARM_STATUS_ALARM,
458                                  DA9063_ALARM_STATUS_ALARM);
459         if (ret < 0) {
460                 dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
461                 return ret;
462         }
463
464         ret = regmap_update_bits(rtc->regmap,
465                                  config->rtc_alarm_year_reg,
466                                  config->rtc_tick_on_mask,
467                                  0);
468         if (ret < 0) {
469                 dev_err(&pdev->dev, "Failed to disable TICKs\n");
470                 return ret;
471         }
472
473         data[RTC_SEC] = 0;
474         ret = regmap_bulk_read(rtc->regmap,
475                                config->rtc_alarm_secs_reg,
476                                &data[config->rtc_data_start],
477                                config->rtc_alarm_len);
478         if (ret < 0) {
479                 dev_err(&pdev->dev, "Failed to read initial alarm data: %d\n",
480                         ret);
481                 return ret;
482         }
483
484         platform_set_drvdata(pdev, rtc);
485
486         rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, DA9063_DRVNAME_RTC,
487                                            &da9063_rtc_ops, THIS_MODULE);
488         if (IS_ERR(rtc->rtc_dev))
489                 return PTR_ERR(rtc->rtc_dev);
490
491         da9063_data_to_tm(data, &rtc->alarm_time, rtc);
492         rtc->rtc_sync = false;
493
494         /*
495          * TODO: some models have alarms on a minute boundary but still support
496          * real hardware interrupts. Add this once the core supports it.
497          */
498         if (config->rtc_data_start != RTC_SEC)
499                 rtc->rtc_dev->uie_unsupported = 1;
500
501         irq_alarm = platform_get_irq_byname(pdev, "ALARM");
502         ret = devm_request_threaded_irq(&pdev->dev, irq_alarm, NULL,
503                                         da9063_alarm_event,
504                                         IRQF_TRIGGER_LOW | IRQF_ONESHOT,
505                                         "ALARM", rtc);
506         if (ret)
507                 dev_err(&pdev->dev, "Failed to request ALARM IRQ %d: %d\n",
508                         irq_alarm, ret);
509
510         return ret;
511 }
512
513 static struct platform_driver da9063_rtc_driver = {
514         .probe          = da9063_rtc_probe,
515         .driver         = {
516                 .name   = DA9063_DRVNAME_RTC,
517                 .of_match_table = da9063_compatible_reg_id_table,
518         },
519 };
520
521 module_platform_driver(da9063_rtc_driver);
522
523 MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
524 MODULE_DESCRIPTION("Real time clock device driver for Dialog DA9063");
525 MODULE_LICENSE("GPL");
526 MODULE_ALIAS("platform:" DA9063_DRVNAME_RTC);