summaryrefslogtreecommitdiff
path: root/drivers/rtc/rtc-pcf50633.c
blob: 48951a16d65dc2cffeaeffb8d4d661461351af92 (plain) (blame)
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
// SPDX-License-Identifier: GPL-2.0-or-later
/* NXP PCF50633 RTC Driver
 *
 * (C) 2006-2008 by Openmoko, Inc.
 * Author: Balaji Rao <balajirrao@openmoko.org>
 * All rights reserved.
 *
 * Broken down from monstrous PCF50633 driver mainly by
 * Harald Welte, Andy Green and Werner Almesberger
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
#include <linux/bcd.h>
#include <linux/err.h>

#include <linux/mfd/pcf50633/core.h>

#define PCF50633_REG_RTCSC	0x59 /* Second */
#define PCF50633_REG_RTCMN	0x5a /* Minute */
#define PCF50633_REG_RTCHR	0x5b /* Hour */
#define PCF50633_REG_RTCWD	0x5c /* Weekday */
#define PCF50633_REG_RTCDT	0x5d /* Day */
#define PCF50633_REG_RTCMT	0x5e /* Month */
#define PCF50633_REG_RTCYR	0x5f /* Year */
#define PCF50633_REG_RTCSCA	0x60 /* Alarm Second */
#define PCF50633_REG_RTCMNA	0x61 /* Alarm Minute */
#define PCF50633_REG_RTCHRA	0x62 /* Alarm Hour */
#define PCF50633_REG_RTCWDA	0x63 /* Alarm Weekday */
#define PCF50633_REG_RTCDTA	0x64 /* Alarm Day */
#define PCF50633_REG_RTCMTA	0x65 /* Alarm Month */
#define PCF50633_REG_RTCYRA	0x66 /* Alarm Year */

enum pcf50633_time_indexes {
	PCF50633_TI_SEC,
	PCF50633_TI_MIN,
	PCF50633_TI_HOUR,
	PCF50633_TI_WKDAY,
	PCF50633_TI_DAY,
	PCF50633_TI_MONTH,
	PCF50633_TI_YEAR,
	PCF50633_TI_EXTENT /* always last */
};

struct pcf50633_time {
	u_int8_t time[PCF50633_TI_EXTENT];
};

struct pcf50633_rtc {
	int alarm_enabled;
	int alarm_pending;

	struct pcf50633 *pcf;
	struct rtc_device *rtc_dev;
};

static void pcf2rtc_time(struct rtc_time *rtc, struct pcf50633_time *pcf)
{
	rtc->tm_sec = bcd2bin(pcf->time[PCF50633_TI_SEC]);
	rtc->tm_min = bcd2bin(pcf->time[PCF50633_TI_MIN]);
	rtc->tm_hour = bcd2bin(pcf->time[PCF50633_TI_HOUR]);
	rtc->tm_wday = bcd2bin(pcf->time[PCF50633_TI_WKDAY]);
	rtc->tm_mday = bcd2bin(pcf->time[PCF50633_TI_DAY]);
	rtc->tm_mon = bcd2bin(pcf->time[PCF50633_TI_MONTH]) - 1;
	rtc->tm_year = bcd2bin(pcf->time[PCF50633_TI_YEAR]) + 100;
}

static void rtc2pcf_time(struct pcf50633_time *pcf, struct rtc_time *rtc)
{
	pcf->time[PCF50633_TI_SEC] = bin2bcd(rtc->tm_sec);
	pcf->time[PCF50633_TI_MIN] = bin2bcd(rtc->tm_min);
	pcf->time[PCF50633_TI_HOUR] = bin2bcd(rtc->tm_hour);
	pcf->time[PCF50633_TI_WKDAY] = bin2bcd(rtc->tm_wday);
	pcf->time[PCF50633_TI_DAY] = bin2bcd(rtc->tm_mday);
	pcf->time[PCF50633_TI_MONTH] = bin2bcd(rtc->tm_mon + 1);
	pcf->time[PCF50633_TI_YEAR] = bin2bcd(rtc->tm_year % 100);
}

static int
pcf50633_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
	struct pcf50633_rtc *rtc = dev_get_drvdata(dev);
	int err;

	if (enabled)
		err = pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
	else
		err = pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);

	if (err < 0)
		return err;

	rtc->alarm_enabled = enabled;

	return 0;
}

static int pcf50633_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	struct pcf50633_rtc *rtc;
	struct pcf50633_time pcf_tm;
	int ret;

	rtc = dev_get_drvdata(dev);

	ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSC,
					    PCF50633_TI_EXTENT,
					    &pcf_tm.time[0]);
	if (ret != PCF50633_TI_EXTENT) {
		dev_err(dev, "Failed to read time\n");
		return -EIO;
	}

	dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x\n",
		pcf_tm.time[PCF50633_TI_DAY],
		pcf_tm.time[PCF50633_TI_MONTH],
		pcf_tm.time[PCF50633_TI_YEAR],
		pcf_tm.time[PCF50633_TI_HOUR],
		pcf_tm.time[PCF50633_TI_MIN],
		pcf_tm.time[PCF50633_TI_SEC]);

	pcf2rtc_time(tm, &pcf_tm);

	dev_dbg(dev, "RTC_TIME: %ptRr\n", tm);

	return 0;
}

static int pcf50633_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	struct pcf50633_rtc *rtc;
	struct pcf50633_time pcf_tm;
	int alarm_masked, ret = 0;

	rtc = dev_get_drvdata(dev);

	dev_dbg(dev, "RTC_TIME: %ptRr\n", tm);

	rtc2pcf_time(&pcf_tm, tm);

	dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x\n",
		pcf_tm.time[PCF50633_TI_DAY],
		pcf_tm.time[PCF50633_TI_MONTH],
		pcf_tm.time[PCF50633_TI_YEAR],
		pcf_tm.time[PCF50633_TI_HOUR],
		pcf_tm.time[PCF50633_TI_MIN],
		pcf_tm.time[PCF50633_TI_SEC]);


	alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);

	if (!alarm_masked)
		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);

	/* Returns 0 on success */
	ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSC,
					     PCF50633_TI_EXTENT,
					     &pcf_tm.time[0]);

	if (!alarm_masked)
		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);

	return ret;
}

static int pcf50633_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct pcf50633_rtc *rtc;
	struct pcf50633_time pcf_tm;
	int ret = 0;

	rtc = dev_get_drvdata(dev);

	alrm->enabled = rtc->alarm_enabled;
	alrm->pending = rtc->alarm_pending;

	ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSCA,
				PCF50633_TI_EXTENT, &pcf_tm.time[0]);
	if (ret != PCF50633_TI_EXTENT) {
		dev_err(dev, "Failed to read time\n");
		return -EIO;
	}

	pcf2rtc_time(&alrm->time, &pcf_tm);

	return rtc_valid_tm(&alrm->time);
}

static int pcf50633_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct pcf50633_rtc *rtc;
	struct pcf50633_time pcf_tm;
	int alarm_masked, ret = 0;

	rtc = dev_get_drvdata(dev);

	rtc2pcf_time(&pcf_tm, &alrm->time);

	/* do like mktime does and ignore tm_wday */
	pcf_tm.time[PCF50633_TI_WKDAY] = 7;

	alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);

	/* disable alarm interrupt */
	if (!alarm_masked)
		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);

	/* Returns 0 on success */
	ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSCA,
				PCF50633_TI_EXTENT, &pcf_tm.time[0]);
	if (!alrm->enabled)
		rtc->alarm_pending = 0;

	if (!alarm_masked || alrm->enabled)
		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
	rtc->alarm_enabled = alrm->enabled;

	return ret;
}

static const struct rtc_class_ops pcf50633_rtc_ops = {
	.read_time		= pcf50633_rtc_read_time,
	.set_time		= pcf50633_rtc_set_time,
	.read_alarm		= pcf50633_rtc_read_alarm,
	.set_alarm		= pcf50633_rtc_set_alarm,
	.alarm_irq_enable	= pcf50633_rtc_alarm_irq_enable,
};

static void pcf50633_rtc_irq(int irq, void *data)
{
	struct pcf50633_rtc *rtc = data;

	rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
	rtc->alarm_pending = 1;
}

static int pcf50633_rtc_probe(struct platform_device *pdev)
{
	struct pcf50633_rtc *rtc;

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

	rtc->pcf = dev_to_pcf50633(pdev->dev.parent);
	platform_set_drvdata(pdev, rtc);
	rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, "pcf50633-rtc",
				&pcf50633_rtc_ops, THIS_MODULE);

	if (IS_ERR(rtc->rtc_dev))
		return PTR_ERR(rtc->rtc_dev);

	pcf50633_register_irq(rtc->pcf, PCF50633_IRQ_ALARM,
					pcf50633_rtc_irq, rtc);
	return 0;
}

static int pcf50633_rtc_remove(struct platform_device *pdev)
{
	struct pcf50633_rtc *rtc;

	rtc = platform_get_drvdata(pdev);
	pcf50633_free_irq(rtc->pcf, PCF50633_IRQ_ALARM);

	return 0;
}

static struct platform_driver pcf50633_rtc_driver = {
	.driver = {
		.name = "pcf50633-rtc",
	},
	.probe = pcf50633_rtc_probe,
	.remove = pcf50633_rtc_remove,
};

module_platform_driver(pcf50633_rtc_driver);

MODULE_DESCRIPTION("PCF50633 RTC driver");
MODULE_AUTHOR("Balaji Rao <balajirrao@openmoko.org>");
MODULE_LICENSE("GPL");