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
|
// SPDX-License-Identifier: GPL-2.0
/*
* Real Time Clock driver for Freescale MC13XXX PMIC
*
* (C) 2009 Sascha Hauer, Pengutronix
* (C) 2009 Uwe Kleine-Koenig, Pengutronix
*/
#include <linux/mfd/mc13xxx.h>
#include <linux/platform_device.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/slab.h>
#include <linux/rtc.h>
#define DRIVER_NAME "mc13xxx-rtc"
#define MC13XXX_RTCTOD 20
#define MC13XXX_RTCTODA 21
#define MC13XXX_RTCDAY 22
#define MC13XXX_RTCDAYA 23
#define SEC_PER_DAY (24 * 60 * 60)
struct mc13xxx_rtc {
struct rtc_device *rtc;
struct mc13xxx *mc13xxx;
int valid;
};
static int mc13xxx_rtc_irq_enable_unlocked(struct device *dev,
unsigned int enabled, int irq)
{
struct mc13xxx_rtc *priv = dev_get_drvdata(dev);
int (*func)(struct mc13xxx *mc13xxx, int irq);
if (!priv->valid)
return -ENODATA;
func = enabled ? mc13xxx_irq_unmask : mc13xxx_irq_mask;
return func(priv->mc13xxx, irq);
}
static int mc13xxx_rtc_alarm_irq_enable(struct device *dev,
unsigned int enabled)
{
struct mc13xxx_rtc *priv = dev_get_drvdata(dev);
int ret;
mc13xxx_lock(priv->mc13xxx);
ret = mc13xxx_rtc_irq_enable_unlocked(dev, enabled, MC13XXX_IRQ_TODA);
mc13xxx_unlock(priv->mc13xxx);
return ret;
}
static int mc13xxx_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct mc13xxx_rtc *priv = dev_get_drvdata(dev);
unsigned int seconds, days1, days2;
if (!priv->valid)
return -ENODATA;
do {
int ret;
ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCDAY, &days1);
if (ret)
return ret;
ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCTOD, &seconds);
if (ret)
return ret;
ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCDAY, &days2);
if (ret)
return ret;
} while (days1 != days2);
rtc_time64_to_tm((time64_t)days1 * SEC_PER_DAY + seconds, tm);
return 0;
}
static int mc13xxx_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct mc13xxx_rtc *priv = dev_get_drvdata(dev);
unsigned int seconds, days;
unsigned int alarmseconds;
int ret;
days = div_s64_rem(rtc_tm_to_time64(tm), SEC_PER_DAY, &seconds);
mc13xxx_lock(priv->mc13xxx);
/*
* temporarily invalidate alarm to prevent triggering it when the day is
* already updated while the time isn't yet.
*/
ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCTODA, &alarmseconds);
if (unlikely(ret))
goto out;
if (alarmseconds < SEC_PER_DAY) {
ret = mc13xxx_reg_write(priv->mc13xxx,
MC13XXX_RTCTODA, 0x1ffff);
if (unlikely(ret))
goto out;
}
/*
* write seconds=0 to prevent a day switch between writing days
* and seconds below
*/
ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCTOD, 0);
if (unlikely(ret))
goto out;
ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCDAY, days);
if (unlikely(ret))
goto out;
ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCTOD, seconds);
if (unlikely(ret))
goto out;
/* restore alarm */
if (alarmseconds < SEC_PER_DAY) {
ret = mc13xxx_reg_write(priv->mc13xxx,
MC13XXX_RTCTODA, alarmseconds);
if (unlikely(ret))
goto out;
}
if (!priv->valid) {
ret = mc13xxx_irq_ack(priv->mc13xxx, MC13XXX_IRQ_RTCRST);
if (unlikely(ret))
goto out;
ret = mc13xxx_irq_unmask(priv->mc13xxx, MC13XXX_IRQ_RTCRST);
}
out:
priv->valid = !ret;
mc13xxx_unlock(priv->mc13xxx);
return ret;
}
static int mc13xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
struct mc13xxx_rtc *priv = dev_get_drvdata(dev);
unsigned int seconds, days;
time64_t s1970;
int enabled, pending;
int ret;
mc13xxx_lock(priv->mc13xxx);
ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCTODA, &seconds);
if (unlikely(ret))
goto out;
if (seconds >= SEC_PER_DAY) {
ret = -ENODATA;
goto out;
}
ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCDAY, &days);
if (unlikely(ret))
goto out;
ret = mc13xxx_irq_status(priv->mc13xxx, MC13XXX_IRQ_TODA,
&enabled, &pending);
out:
mc13xxx_unlock(priv->mc13xxx);
if (ret)
return ret;
alarm->enabled = enabled;
alarm->pending = pending;
s1970 = (time64_t)days * SEC_PER_DAY + seconds;
rtc_time64_to_tm(s1970, &alarm->time);
dev_dbg(dev, "%s: %lld\n", __func__, (long long)s1970);
return 0;
}
static int mc13xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
struct mc13xxx_rtc *priv = dev_get_drvdata(dev);
time64_t s1970;
u32 seconds, days;
int ret;
mc13xxx_lock(priv->mc13xxx);
/* disable alarm to prevent false triggering */
ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCTODA, 0x1ffff);
if (unlikely(ret))
goto out;
ret = mc13xxx_irq_ack(priv->mc13xxx, MC13XXX_IRQ_TODA);
if (unlikely(ret))
goto out;
s1970 = rtc_tm_to_time64(&alarm->time);
dev_dbg(dev, "%s: %s %lld\n", __func__, alarm->enabled ? "on" : "off",
(long long)s1970);
ret = mc13xxx_rtc_irq_enable_unlocked(dev, alarm->enabled,
MC13XXX_IRQ_TODA);
if (unlikely(ret))
goto out;
days = div_s64_rem(s1970, SEC_PER_DAY, &seconds);
ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCDAYA, days);
if (unlikely(ret))
goto out;
ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCTODA, seconds);
out:
mc13xxx_unlock(priv->mc13xxx);
return ret;
}
static irqreturn_t mc13xxx_rtc_alarm_handler(int irq, void *dev)
{
struct mc13xxx_rtc *priv = dev;
struct mc13xxx *mc13xxx = priv->mc13xxx;
rtc_update_irq(priv->rtc, 1, RTC_IRQF | RTC_AF);
mc13xxx_irq_ack(mc13xxx, irq);
return IRQ_HANDLED;
}
static const struct rtc_class_ops mc13xxx_rtc_ops = {
.read_time = mc13xxx_rtc_read_time,
.set_time = mc13xxx_rtc_set_time,
.read_alarm = mc13xxx_rtc_read_alarm,
.set_alarm = mc13xxx_rtc_set_alarm,
.alarm_irq_enable = mc13xxx_rtc_alarm_irq_enable,
};
static irqreturn_t mc13xxx_rtc_reset_handler(int irq, void *dev)
{
struct mc13xxx_rtc *priv = dev;
struct mc13xxx *mc13xxx = priv->mc13xxx;
priv->valid = 0;
mc13xxx_irq_mask(mc13xxx, irq);
return IRQ_HANDLED;
}
static int __init mc13xxx_rtc_probe(struct platform_device *pdev)
{
int ret;
struct mc13xxx_rtc *priv;
struct mc13xxx *mc13xxx;
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
mc13xxx = dev_get_drvdata(pdev->dev.parent);
priv->mc13xxx = mc13xxx;
priv->valid = 1;
priv->rtc = devm_rtc_allocate_device(&pdev->dev);
if (IS_ERR(priv->rtc))
return PTR_ERR(priv->rtc);
platform_set_drvdata(pdev, priv);
priv->rtc->ops = &mc13xxx_rtc_ops;
/* 15bit days + hours, minutes, seconds */
priv->rtc->range_max = (timeu64_t)(1 << 15) * SEC_PER_DAY - 1;
mc13xxx_lock(mc13xxx);
mc13xxx_irq_ack(mc13xxx, MC13XXX_IRQ_RTCRST);
ret = mc13xxx_irq_request(mc13xxx, MC13XXX_IRQ_RTCRST,
mc13xxx_rtc_reset_handler, DRIVER_NAME, priv);
if (ret)
goto err_irq_request;
ret = mc13xxx_irq_request_nounmask(mc13xxx, MC13XXX_IRQ_TODA,
mc13xxx_rtc_alarm_handler, DRIVER_NAME, priv);
if (ret)
goto err_irq_request;
mc13xxx_unlock(mc13xxx);
ret = rtc_register_device(priv->rtc);
if (ret)
goto err_irq_request;
return 0;
err_irq_request:
mc13xxx_irq_free(mc13xxx, MC13XXX_IRQ_TODA, priv);
mc13xxx_irq_free(mc13xxx, MC13XXX_IRQ_RTCRST, priv);
mc13xxx_unlock(mc13xxx);
return ret;
}
static int mc13xxx_rtc_remove(struct platform_device *pdev)
{
struct mc13xxx_rtc *priv = platform_get_drvdata(pdev);
mc13xxx_lock(priv->mc13xxx);
mc13xxx_irq_free(priv->mc13xxx, MC13XXX_IRQ_TODA, priv);
mc13xxx_irq_free(priv->mc13xxx, MC13XXX_IRQ_RTCRST, priv);
mc13xxx_unlock(priv->mc13xxx);
return 0;
}
static const struct platform_device_id mc13xxx_rtc_idtable[] = {
{
.name = "mc13783-rtc",
}, {
.name = "mc13892-rtc",
}, {
.name = "mc34708-rtc",
},
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(platform, mc13xxx_rtc_idtable);
static struct platform_driver mc13xxx_rtc_driver = {
.id_table = mc13xxx_rtc_idtable,
.remove = mc13xxx_rtc_remove,
.driver = {
.name = DRIVER_NAME,
},
};
module_platform_driver_probe(mc13xxx_rtc_driver, &mc13xxx_rtc_probe);
MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
MODULE_DESCRIPTION("RTC driver for Freescale MC13XXX PMIC");
MODULE_LICENSE("GPL v2");
|
