1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
|
/*
* RTC driver for Rockchip RK808
*
* Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
*
* Author: Chris Zhong <zyw@rock-chips.com>
* Author: Zhang Qing <zhangqing@rock-chips.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/rtc.h>
#include <linux/bcd.h>
#include <linux/mfd/rk808.h>
#include <linux/platform_device.h>
#include <linux/i2c.h>
/* RTC_CTRL_REG bitfields */
#define BIT_RTC_CTRL_REG_STOP_RTC_M BIT(0)
/* RK808 has a shadowed register for saving a "frozen" RTC time.
* When user setting "GET_TIME" to 1, the time will save in this shadowed
* register. If set "READSEL" to 1, user read rtc time register, actually
* get the time of that moment. If we need the real time, clr this bit.
*/
#define BIT_RTC_CTRL_REG_RTC_GET_TIME BIT(6)
#define BIT_RTC_CTRL_REG_RTC_READSEL_M BIT(7)
#define BIT_RTC_INTERRUPTS_REG_IT_ALARM_M BIT(3)
#define RTC_STATUS_MASK 0xFE
#define SECONDS_REG_MSK 0x7F
#define MINUTES_REG_MAK 0x7F
#define HOURS_REG_MSK 0x3F
#define DAYS_REG_MSK 0x3F
#define MONTHS_REG_MSK 0x1F
#define YEARS_REG_MSK 0xFF
#define WEEKS_REG_MSK 0x7
/* REG_SECONDS_REG through REG_YEARS_REG is how many registers? */
#define NUM_TIME_REGS (RK808_WEEKS_REG - RK808_SECONDS_REG + 1)
#define NUM_ALARM_REGS (RK808_ALARM_YEARS_REG - RK808_ALARM_SECONDS_REG + 1)
struct rk808_rtc {
struct rk808 *rk808;
struct rtc_device *rtc;
int irq;
};
/* Read current time and date in RTC */
static int rk808_rtc_readtime(struct device *dev, struct rtc_time *tm)
{
struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
struct rk808 *rk808 = rk808_rtc->rk808;
u8 rtc_data[NUM_TIME_REGS];
int ret;
/* Force an update of the shadowed registers right now */
ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
BIT_RTC_CTRL_REG_RTC_GET_TIME,
BIT_RTC_CTRL_REG_RTC_GET_TIME);
if (ret) {
dev_err(dev, "Failed to update bits rtc_ctrl: %d\n", ret);
return ret;
}
/*
* After we set the GET_TIME bit, the rtc time can't be read
* immediately. So we should wait up to 31.25 us, about one cycle of
* 32khz. If we clear the GET_TIME bit here, the time of i2c transfer
* certainly more than 31.25us: 16 * 2.5us at 400kHz bus frequency.
*/
ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
BIT_RTC_CTRL_REG_RTC_GET_TIME,
0);
if (ret) {
dev_err(dev, "Failed to update bits rtc_ctrl: %d\n", ret);
return ret;
}
ret = regmap_bulk_read(rk808->regmap, RK808_SECONDS_REG,
rtc_data, NUM_TIME_REGS);
if (ret) {
dev_err(dev, "Failed to bulk read rtc_data: %d\n", ret);
return ret;
}
tm->tm_sec = bcd2bin(rtc_data[0] & SECONDS_REG_MSK);
tm->tm_min = bcd2bin(rtc_data[1] & MINUTES_REG_MAK);
tm->tm_hour = bcd2bin(rtc_data[2] & HOURS_REG_MSK);
tm->tm_mday = bcd2bin(rtc_data[3] & DAYS_REG_MSK);
tm->tm_mon = (bcd2bin(rtc_data[4] & MONTHS_REG_MSK)) - 1;
tm->tm_year = (bcd2bin(rtc_data[5] & YEARS_REG_MSK)) + 100;
tm->tm_wday = bcd2bin(rtc_data[6] & WEEKS_REG_MSK);
dev_dbg(dev, "RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
tm->tm_wday, tm->tm_hour , tm->tm_min, tm->tm_sec);
return ret;
}
/* Set current time and date in RTC */
static int rk808_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
struct rk808 *rk808 = rk808_rtc->rk808;
u8 rtc_data[NUM_TIME_REGS];
int ret;
rtc_data[0] = bin2bcd(tm->tm_sec);
rtc_data[1] = bin2bcd(tm->tm_min);
rtc_data[2] = bin2bcd(tm->tm_hour);
rtc_data[3] = bin2bcd(tm->tm_mday);
rtc_data[4] = bin2bcd(tm->tm_mon + 1);
rtc_data[5] = bin2bcd(tm->tm_year - 100);
rtc_data[6] = bin2bcd(tm->tm_wday);
dev_dbg(dev, "set RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
tm->tm_wday, tm->tm_hour , tm->tm_min, tm->tm_sec);
/* Stop RTC while updating the RTC registers */
ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
BIT_RTC_CTRL_REG_STOP_RTC_M,
BIT_RTC_CTRL_REG_STOP_RTC_M);
if (ret) {
dev_err(dev, "Failed to update RTC control: %d\n", ret);
return ret;
}
ret = regmap_bulk_write(rk808->regmap, RK808_SECONDS_REG,
rtc_data, NUM_TIME_REGS);
if (ret) {
dev_err(dev, "Failed to bull write rtc_data: %d\n", ret);
return ret;
}
/* Start RTC again */
ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
BIT_RTC_CTRL_REG_STOP_RTC_M, 0);
if (ret) {
dev_err(dev, "Failed to update RTC control: %d\n", ret);
return ret;
}
return 0;
}
/* Read alarm time and date in RTC */
static int rk808_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
struct rk808 *rk808 = rk808_rtc->rk808;
u8 alrm_data[NUM_ALARM_REGS];
uint32_t int_reg;
int ret;
ret = regmap_bulk_read(rk808->regmap, RK808_ALARM_SECONDS_REG,
alrm_data, NUM_ALARM_REGS);
alrm->time.tm_sec = bcd2bin(alrm_data[0] & SECONDS_REG_MSK);
alrm->time.tm_min = bcd2bin(alrm_data[1] & MINUTES_REG_MAK);
alrm->time.tm_hour = bcd2bin(alrm_data[2] & HOURS_REG_MSK);
alrm->time.tm_mday = bcd2bin(alrm_data[3] & DAYS_REG_MSK);
alrm->time.tm_mon = (bcd2bin(alrm_data[4] & MONTHS_REG_MSK)) - 1;
alrm->time.tm_year = (bcd2bin(alrm_data[5] & YEARS_REG_MSK)) + 100;
ret = regmap_read(rk808->regmap, RK808_RTC_INT_REG, &int_reg);
if (ret) {
dev_err(dev, "Failed to read RTC INT REG: %d\n", ret);
return ret;
}
dev_dbg(dev, "alrm read RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
1900 + alrm->time.tm_year, alrm->time.tm_mon + 1,
alrm->time.tm_mday, alrm->time.tm_wday, alrm->time.tm_hour,
alrm->time.tm_min, alrm->time.tm_sec);
alrm->enabled = (int_reg & BIT_RTC_INTERRUPTS_REG_IT_ALARM_M) ? 1 : 0;
return 0;
}
static int rk808_rtc_stop_alarm(struct rk808_rtc *rk808_rtc)
{
struct rk808 *rk808 = rk808_rtc->rk808;
int ret;
ret = regmap_update_bits(rk808->regmap, RK808_RTC_INT_REG,
BIT_RTC_INTERRUPTS_REG_IT_ALARM_M, 0);
return ret;
}
static int rk808_rtc_start_alarm(struct rk808_rtc *rk808_rtc)
{
struct rk808 *rk808 = rk808_rtc->rk808;
int ret;
ret = regmap_update_bits(rk808->regmap, RK808_RTC_INT_REG,
BIT_RTC_INTERRUPTS_REG_IT_ALARM_M,
BIT_RTC_INTERRUPTS_REG_IT_ALARM_M);
return ret;
}
static int rk808_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
struct rk808 *rk808 = rk808_rtc->rk808;
u8 alrm_data[NUM_ALARM_REGS];
int ret;
ret = rk808_rtc_stop_alarm(rk808_rtc);
if (ret) {
dev_err(dev, "Failed to stop alarm: %d\n", ret);
return ret;
}
dev_dbg(dev, "alrm set RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
1900 + alrm->time.tm_year, alrm->time.tm_mon + 1,
alrm->time.tm_mday, alrm->time.tm_wday, alrm->time.tm_hour,
alrm->time.tm_min, alrm->time.tm_sec);
alrm_data[0] =
|