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
|
/*
* TI LP8788 MFD - rtc driver
*
* Copyright 2012 Texas Instruments
*
* Author: Milo(Woogyom) Kim <milo.kim@ti.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/err.h>
#include <linux/irqdomain.h>
#include <linux/mfd/lp8788.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
#include <linux/slab.h>
/* register address */
#define LP8788_INTEN_3 0x05
#define LP8788_RTC_UNLOCK 0x64
#define LP8788_RTC_SEC 0x70
#define LP8788_ALM1_SEC 0x77
#define LP8788_ALM1_EN 0x7D
#define LP8788_ALM2_SEC 0x7E
#define LP8788_ALM2_EN 0x84
/* mask/shift bits */
#define LP8788_INT_RTC_ALM1_M BIT(1) /* Addr 05h */
#define LP8788_INT_RTC_ALM1_S 1
#define LP8788_INT_RTC_ALM2_M BIT(2) /* Addr 05h */
#define LP8788_INT_RTC_ALM2_S 2
#define LP8788_ALM_EN_M BIT(7) /* Addr 7Dh or 84h */
#define LP8788_ALM_EN_S 7
#define DEFAULT_ALARM_SEL LP8788_ALARM_1
#define LP8788_MONTH_OFFSET 1
#define LP8788_BASE_YEAR 2000
#define MAX_WDAY_BITS 7
#define LP8788_WDAY_SET 1
#define RTC_UNLOCK 0x1
#define RTC_LATCH 0x2
#define ALARM_IRQ_FLAG (RTC_IRQF | RTC_AF)
enum lp8788_time {
LPTIME_SEC,
LPTIME_MIN,
LPTIME_HOUR,
LPTIME_MDAY,
LPTIME_MON,
LPTIME_YEAR,
LPTIME_WDAY,
LPTIME_MAX,
};
struct lp8788_rtc {
struct lp8788 *lp;
struct rtc_device *rdev;
enum lp8788_alarm_sel alarm;
int irq;
};
static const u8 addr_alarm_sec[LP8788_ALARM_MAX] = {
LP8788_ALM1_SEC,
LP8788_ALM2_SEC,
};
static const u8 addr_alarm_en[LP8788_ALARM_MAX] = {
LP8788_ALM1_EN,
LP8788_ALM2_EN,
};
static const u8 mask_alarm_en[LP8788_ALARM_MAX] = {
LP8788_INT_RTC_ALM1_M,
LP8788_INT_RTC_ALM2_M,
};
static const u8 shift_alarm_en[LP8788_ALARM_MAX] = {
LP8788_INT_RTC_ALM1_S,
LP8788_INT_RTC_ALM2_S,
};
static int _to_tm_wday(u8 lp8788_wday)
{
int i;
if (lp8788_wday == 0)
return 0;
/* lookup defined weekday from read register value */
for (i = 0; i < MAX_WDAY_BITS; i++) {
if ((lp8788_wday >> i) == LP8788_WDAY_SET)
break;
}
return i + 1;
}
static inline int _to_lp8788_wday(int tm_wday)
{
return LP8788_WDAY_SET << (tm_wday - 1);
}
static void lp8788_rtc_unlock(struct lp8788 *lp)
{
lp8788_write_byte(lp, LP8788_RTC_UNLOCK, RTC_UNLOCK);
lp8788_write_byte(lp, LP8788_RTC_UNLOCK, RTC_LATCH);
}
static int lp8788_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct lp8788_rtc *rtc = dev_get_drvdata(dev);
struct lp8788 *lp = rtc->lp;
u8 data[LPTIME_MAX];
int ret;
lp8788_rtc_unlock(lp);
ret = lp8788_read_multi_bytes(lp, LP8788_RTC_SEC, data, LPTIME_MAX);
if (ret)
return ret;
tm->tm_sec = data[LPTIME_SEC];
tm->tm_min = data[LPTIME_MIN];
tm->tm_hour = data[LPTIME_HOUR];
tm->tm_mday = data[LPTIME_MDAY];
tm->tm_mon = data[LPTIME_MON] - LP8788_MONTH_OFFSET;
tm->tm_year = data[LPTIME_YEAR] + LP8788_BASE_YEAR - 1900;
tm->tm_wday = _to_tm_wday(data[LPTIME_WDAY]);
return 0;
}
static int lp8788_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct lp8788_rtc *rtc = dev_get_drvdata(dev);
struct lp8788 *lp = rtc->lp;
u8 data[LPTIME_MAX - 1];
int ret, i, year;
year = tm->tm_year + 1900 - LP8788_BASE_YEAR;
if (year < 0) {
dev_err(lp->dev, "invalid year: %d\n", year);
return -EINVAL;
}
/* because rtc weekday is a readonly register, do not update */
data[LPTIME_SEC] = tm->tm_sec;
data[LPTIME_MIN] = tm->tm_min;
data[LPTIME_HOUR] = tm->tm_hour;
data[LPTIME_MDAY] = tm->tm_mday;
data[LPTIME_MON] = tm->tm_mon + LP8788_MONTH_OFFSET;
data[LPTIME_YEAR] = year;
for (i = 0; i < ARRAY_SIZE(data); i++) {
ret = lp8788_write_byte(lp, LP8788_RTC_SEC + i, data[i]);
if (ret)
return ret;
}
return 0;
}
static int lp8788_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
struct lp8788_rtc *rtc = dev_get_drvdata(dev);
struct lp8788 *lp = rtc->lp;
struct rtc_time *tm = &alarm->time;
u8 addr, data[LPTIME_MAX];
int ret;
addr = addr_alarm_sec[rtc->alarm];
ret = lp8788_read_multi_bytes(lp, addr, data, LPTIME_MAX);
if (ret)
return ret;
tm->tm_sec = data[LPTIME_SEC];
tm->tm_min = data[LPTIME_MIN];
tm->tm_hour = data[LPTIME_HOUR];
tm->tm_mday = data[LPTIME_MDAY];
tm->tm_mon = data[LPTIME_MON] - LP8788_MONTH_OFFSET;
tm->tm_year = data[LPTIME_YEAR] + LP8788_BASE_YEAR - 1900;
tm->tm_wday = _to_tm_wday(data[LPTIME_WDAY]);
alarm->enabled = data[LPTIME_WDAY] & LP8788_ALM_EN_M;
return 0;
}
static int lp8788_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
struct lp8788_rtc *rtc = dev_get_drvdata(dev);
struct lp8788 *lp = rtc->lp;
struct rtc_time *tm = &alarm->time;
u8 addr, data[LPTIME_MAX];
int ret, i, year;
year = tm->tm_year + 1900 - LP8788_BASE_YEAR;
if (year < 0) {
dev_err(lp->dev, "invalid year: %d\n", year);
return -EINVAL;
}
data[LPTIME_SEC] = tm->tm_sec;
data[LPTIME_MIN] = tm->tm_min;
data[LPTIME_HOUR] = tm->tm_hour;
data[LPTIME_MDAY] = tm->tm_mday;
data[LPTIME_MON] = tm->tm_mon + LP8788_MONTH_OFFSET;
data[LPTIME_YEAR] = year;
data[LPTIME_WDAY] = _to_lp8788_wday(tm->tm_wday);
for (i = 0; i < ARRAY_SIZE(data); i++) {
addr = addr_alarm_sec[rtc->alarm] + i;
ret = lp8788_write_byte(lp, addr, data[i]);
if (ret)
return ret;
}
alarm->enabled = 1;
addr = addr_alarm_en[rtc->alarm];
return lp8788_update_bits(lp, addr, LP8788_ALM_EN_M,
alarm->enabled << LP8788_ALM_EN_S);
}
static int lp8788_alarm_irq_enable(struct device *dev, unsigned int enable)
{
struct lp8788_rtc *rtc = dev_get_drvdata(dev);
struct lp8788 *lp = rtc->lp;
u8 mask, shift;
if (!rtc->irq)
return -EIO;
mask = mask_alarm_en[rtc->alarm];
shift = shift_alarm_en[rtc->alarm];
return lp8788_update_bits(lp, LP8788_INTEN_3, mask, enable << shift);
}
static const struct rtc_class_ops lp8788_rtc_ops = {
.read_time = lp8788_rtc_read_time,
.set_time = lp8788_rtc_set_time,
.read_alarm = lp8788_read_alarm,
.set_alarm = lp8788_set_alarm,
.alarm_irq_enable = lp8788_alarm_irq_enable,
};
static irqreturn_t lp8788_alarm_irq_handler(int irq, void *ptr)
{
struct lp8788_rtc *rtc = ptr;
rtc_update_irq(rtc->rdev, 1, ALARM_IRQ_FLAG);
return IRQ_HANDLED;
}
static int lp8788_alarm_irq_register(struct platform_device *pdev,
struct lp8788_rtc *rtc)
{
struct resource *r;
struct lp8788 *lp = rtc->lp;
struct irq_domain *irqdm = lp->irqdm;
int irq;
rtc->irq = 0;
/* even the alarm IRQ number is not specified, rtc time should work */
r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, LP8788_ALM_IRQ);
if (!r)
return 0;
if (rtc->alarm == LP8788_ALARM_1)
irq = r->start;
else
irq = r->end;
rtc->irq = irq_create_mapping(irqdm, irq);
return devm_request_threaded_irq(&pdev->dev, rtc->irq, NULL,
lp8788_alarm_irq_handler,
0, LP8788_ALM_IRQ, rtc);
}
static int lp8788_rtc_probe(struct platform_device *pdev)
{
struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);
struct lp8788_rtc *rtc;
struct device *dev = &pdev->dev;
rtc = devm_kzalloc(dev, sizeof(struct lp8788_rtc), GFP_KERNEL);
if (!rtc)
return -ENOMEM;
rtc->lp = lp;
rtc->alarm = lp->pdata ? lp->pdata->alarm_sel : DEFAULT_ALARM_SEL;
platform_set_drvdata(pdev, rtc);
device_init_wakeup(dev, 1);
rtc->rdev = devm_rtc_device_register(dev, "lp8788_rtc",
&lp8788_rtc_ops, THIS_MODULE);
if (IS_ERR(rtc->rdev)) {
dev_err(dev, "can not register rtc device\n");
return PTR_ERR(rtc->rdev);
}
if (lp8788_alarm_irq_register(pdev, rtc))
dev_warn(lp->dev, "no rtc irq handler\n");
return 0;
}
static int lp8788_rtc_remove(struct platform_device *pdev)
{
return 0;
}
static struct platform_driver lp8788_rtc_driver = {
.probe = lp8788_rtc_probe,
.remove = lp8788_rtc_remove,
.driver = {
.name = LP8788_DEV_RTC,
.owner = THIS_MODULE,
},
};
module_platform_driver(lp8788_rtc_driver);
MODULE_DESCRIPTION("Texas Instruments LP8788 RTC Driver");
MODULE_AUTHOR("Milo Kim");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:lp8788-rtc");
|
