summaryrefslogtreecommitdiffstats
path: root/drivers/rtc/rtc-da9052.c
blob: acc3e5a1f61afa60434c9db4aab117217207013c (plain)
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
/*
 * Real time clock driver for DA9052
 *
 * Copyright(c) 2012 Dialog Semiconductor Ltd.
 *
 * Author: Dajun Dajun Chen <dajun.chen@diasemi.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 */

#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
#include <linux/err.h>
#include <linux/delay.h>

#include <linux/mfd/da9052/da9052.h>
#include <linux/mfd/da9052/reg.h>

#define rtc_err(rtc, fmt, ...) \
		dev_err(rtc->da9052->dev, "%s: " fmt, __func__, ##__VA_ARGS__)

#define DA9052_GET_TIME_RETRIES 5

struct da9052_rtc {
	struct rtc_device *rtc;
	struct da9052 *da9052;
};

static int da9052_rtc_enable_alarm(struct da9052_rtc *rtc, bool enable)
{
	int ret;
	if (enable) {
		ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,
				DA9052_ALARM_Y_ALARM_ON|DA9052_ALARM_Y_TICK_ON,
				DA9052_ALARM_Y_ALARM_ON);
		if (ret != 0)
			rtc_err(rtc, "Failed to enable ALM: %d\n", ret);
	} else {
		ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,
			DA9052_ALARM_Y_ALARM_ON|DA9052_ALARM_Y_TICK_ON, 0);
		if (ret != 0)
			rtc_err(rtc, "Write error: %d\n", ret);
	}
	return ret;
}

static irqreturn_t da9052_rtc_irq(int irq, void *data)
{
	struct da9052_rtc *rtc = data;

	rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);

	return IRQ_HANDLED;
}

static int da9052_read_alarm(struct da9052_rtc *rtc, struct rtc_time *rtc_tm)
{
	int ret;
	uint8_t v[2][5];
	int idx = 1;
	int timeout = DA9052_GET_TIME_RETRIES;

	ret = da9052_group_read(rtc->da9052, DA9052_ALARM_MI_REG, 5, &v[0][0]);
	if (ret) {
		rtc_err(rtc, "Failed to group read ALM: %d\n", ret);
		return ret;
	}

	do {
		ret = da9052_group_read(rtc->da9052,
					DA9052_ALARM_MI_REG, 5, &v[idx][0]);
		if (ret) {
			rtc_err(rtc, "Failed to group read ALM: %d\n", ret);
			return ret;
		}

		if (memcmp(&v[0][0], &v[1][0], 5) == 0) {
			rtc_tm->tm_year = (v[0][4] & DA9052_RTC_YEAR) + 100;
			rtc_tm->tm_mon  = (v[0][3] & DA9052_RTC_MONTH) - 1;
			rtc_tm->tm_mday = v[0][2] & DA9052_RTC_DAY;
			rtc_tm->tm_hour = v[0][1] & DA9052_RTC_HOUR;
			rtc_tm->tm_min  = v[0][0] & DA9052_RTC_MIN;

			ret = rtc_valid_tm(rtc_tm);
			return ret;
		}

		idx = (1-idx);
		msleep(20);

	} while (timeout--);

	rtc_err(rtc, "Timed out reading alarm time\n");

	return -EIO;
}

static int da9052_set_alarm(struct da9052_rtc *rtc, struct rtc_time *rtc_tm)
{
	struct da9052 *da9052 = rtc->da9052;
	unsigned long alm_time;
	int ret;
	uint8_t v[3];

	ret = rtc_tm_to_time(rtc_tm, &alm_time);
	if (ret != 0)
		return ret;

	if (rtc_tm->tm_sec > 0) {
		alm_time += 60 - rtc_tm->tm_sec;
		rtc_time_to_tm(alm_time, rtc_tm);
	}
	BUG_ON(rtc_tm->tm_sec); /* it will cause repeated irqs if not zero */

	rtc_tm->tm_year -= 100;
	rtc_tm->tm_mon += 1;

	ret = da9052_reg_update(da9052, DA9052_ALARM_MI_REG,
				DA9052_RTC_MIN, rtc_tm->tm_min);
	if (ret != 0) {
		rtc_err(rtc, "Failed to write ALRM MIN: %d\n", ret);
		return ret;
	}

	v[0] = rtc_tm->tm_hour;
	v[1] = rtc_tm->tm_mday;
	v[2] = rtc_tm->tm_mon;

	ret = da9052_group_write(da9052, DA9052_ALARM_H_REG, 3, v);
	if (ret < 0)
		return ret;

	ret = da9052_reg_update(da9052, DA9052_ALARM_Y_REG,
				DA9052_RTC_YEAR, rtc_tm->tm_year);
	if (ret != 0)
		rtc_err(rtc, "Failed to write ALRM YEAR: %d\n", ret);

	return ret;
}

static int da9052_rtc_get_alarm_status(struct da9052_rtc *rtc)
{
	int ret;

	ret = da9052_reg_read(rtc->da9052, DA9052_ALARM_Y_REG);
	if (ret < 0) {
		rtc_err(rtc, "Failed to read ALM: %d\n", ret);
		return ret;
	}

	return !!(ret&DA9052_ALARM_Y_ALARM_ON);
}

static int da9052_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm)
{
	struct da9052_rtc *rtc = dev_get_drvdata(dev);
	int ret;
	uint8_t v[2][6];
	int idx = 1;
	int timeout = DA9052_GET_TIME_RETRIES;

	ret = da9052_group_read(rtc->da9052, DA9052_COUNT_S_REG, 6, &v[0][0]);
	if (ret) {
		rtc_err(rtc, "Failed to read RTC time : %d\n", ret);
		return ret;
	}

	do {
		ret = da9052_group_read(rtc->da9052,
					DA9052_COUNT_S_REG, 6, &v[idx][0]);
		if (ret) {
			rtc_err(rtc, "Failed to read RTC time : %d\n", ret);
			return ret;
		}

		if (memcmp(&v[0][0], &v[1][0], 6) == 0) {
			rtc_tm->tm_year = (v[0][5] & DA9052_RTC_YEAR) + 100;
			rtc_tm->tm_mon  = (v[0][4] & DA9052_RTC_MONTH) - 1;
			rtc_tm->tm_mday = v[0][3] & DA9052_RTC_DAY;
			rtc_tm->tm_hour = v[0][2] & DA9052_RTC_HOUR;
			rtc_tm->tm_min  = v[0][1] & DA9052_RTC_MIN;
			rtc_tm->tm_sec  = v[0][0] & DA9052_RTC_SEC;

			ret = rtc_valid_tm(rtc_tm);
			return ret;
		}

		idx = (1-idx);
		msleep(20);

	} while (timeout--);

	rtc_err(rtc, "Timed out reading time\n");

	return -EIO;
}

static int da9052_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	struct da9052_rtc *rtc;
	uint8_t v[6];
	int ret;

	/* DA9052 only has 6 bits for year - to represent 2000-2063 */
	if ((tm->tm_year < 100) || (tm->tm_year > 163))
		return -EINVAL;

	rtc = dev_get_drvdata(dev);

	v[0] = tm->tm_sec;
	v[1] = tm->tm_min;
	v[2] = tm->tm_hour;
	v[3] = tm->tm_mday;
	v[4] = tm->tm_mon + 1;
	v[5] = tm->tm_year - 100;

	ret = da9052_group_write(rtc->da9052, DA9052_COUNT_S_REG, 6, v);
	if (ret < 0)
		rtc_err(rtc, "failed to set RTC time: %d\n", ret);
	return ret;
}

static int da9052_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	int ret;
	struct rtc_time *tm = &alrm->time;
	struct da9052_rtc *rtc = dev_get_drvdata(dev);

	ret = da9052_read_alarm(rtc, tm);
	if (ret < 0) {
		rtc_err(rtc, "failed to read RTC alarm: %d\n", ret);
		return ret;
	}

	alrm->enabled = da9052_rtc_get_alarm_status(rtc);
	return 0;
}

static int da9052_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	int ret;
	struct rtc_time *tm = &alrm->time;
	struct da9052_rtc *rtc = dev_get_drvdata(dev);

	/* DA9052 only has 6 bits for year - to represent 2000-2063 */
	if ((tm->tm_year < 100) || (tm->tm_year > 163))
		return -EINVAL;

	ret = da9052_rtc_enable_alarm(rtc, 0);
	if (ret < 0)
		return ret;

	ret = da9052_set_alarm(rtc, tm);
	if (ret < 0)
		return ret;

	ret = da9052_rtc_enable_alarm(rtc, 1);
	return ret;
}

static int da9052_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
	struct da9052_rtc *rtc = dev_get_drvdata(dev);

	return da9052_rtc_enable_alarm(rtc, enabled);
}

static const struct rtc_class_ops da9052_rtc_ops = {
	.read_time	= da9052_rtc_read_time,
	.set_time	= da9052_rtc_set_time,
	.read_alarm	= da9052_rtc_read_alarm,
	.set_alarm	= da9052_rtc_set_alarm,
	.alarm_irq_enable = da9052_rtc_alarm_irq_enable,
};

static int da9052_rtc_probe(struct platform_device *pdev)
{
	struct da9052_rtc *rtc;
	int ret;

	rtc = devm_kzalloc(&pdev->dev, sizeof(struct da9052_rtc), GFP_KERNEL);
	if (!rtc)
		return -ENOMEM;

	rtc->da9052 = dev_get_drvdata(pdev->dev.parent);
	platform_set_drvdata(pdev, rtc);

	ret = da9052_reg_write(rtc->da9052, DA9052_BBAT_CONT_REG, 0xFE);
	if (ret < 0) {
		rtc_err(rtc,
			"Failed to setup RTC battery charging: %d\n", ret);
		return ret;
	}

	ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,
				DA9052_ALARM_Y_TICK_ON, 0);
	if (ret != 0)
		rtc_err(rtc, "Failed to disable TICKS: %d\n", ret);

	ret = da9052_request_irq(rtc->da9052, DA9052_IRQ_ALARM, "ALM",
				da9052_rtc_irq, rtc);
	if (ret != 0) {
		rtc_err(rtc, "irq registration failed: %d\n", ret);
		return ret;
	}

	rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
				       &da9052_rtc_ops, THIS_MODULE);
	return PTR_ERR_OR_ZERO(rtc->rtc);
}

static struct platform_driver da9052_rtc_driver = {
	.probe	= da9052_rtc_probe,
	.driver = {
		.name	= "da9052-rtc",
	},
};

module_platform_driver(da9052_rtc_driver);

MODULE_AUTHOR("Anthony Olech <Anthony.Olech@diasemi.com>");
MODULE_DESCRIPTION("RTC driver for Dialog DA9052 PMIC");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:da9052-rtc");