aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/rtc/rtc-max8925.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/rtc/rtc-max8925.c')
-rw-r--r--drivers/rtc/rtc-max8925.c314
1 files changed, 314 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-max8925.c b/drivers/rtc/rtc-max8925.c
new file mode 100644
index 000000000000..acdbb1760187
--- /dev/null
+++ b/drivers/rtc/rtc-max8925.c
@@ -0,0 +1,314 @@
1/*
2 * RTC driver for Maxim MAX8925
3 *
4 * Copyright (C) 2009-2010 Marvell International Ltd.
5 * Haojian Zhuang <haojian.zhuang@marvell.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12#include <linux/module.h>
13#include <linux/i2c.h>
14#include <linux/rtc.h>
15#include <linux/platform_device.h>
16#include <linux/mfd/max8925.h>
17
18enum {
19 RTC_SEC = 0,
20 RTC_MIN,
21 RTC_HOUR,
22 RTC_WEEKDAY,
23 RTC_DATE,
24 RTC_MONTH,
25 RTC_YEAR1,
26 RTC_YEAR2,
27};
28
29#define MAX8925_RTC_SEC 0x00
30#define MAX8925_RTC_MIN 0x01
31#define MAX8925_RTC_HOUR 0x02
32#define MAX8925_RTC_WEEKDAY 0x03
33#define MAX8925_RTC_DATE 0x04
34#define MAX8925_RTC_MONTH 0x05
35#define MAX8925_RTC_YEAR1 0x06
36#define MAX8925_RTC_YEAR2 0x07
37#define MAX8925_ALARM0_SEC 0x08
38#define MAX8925_ALARM0_MIN 0x09
39#define MAX8925_ALARM0_HOUR 0x0a
40#define MAX8925_ALARM0_WEEKDAY 0x0b
41#define MAX8925_ALARM0_DATE 0x0c
42#define MAX8925_ALARM0_MON 0x0d
43#define MAX8925_ALARM0_YEAR1 0x0e
44#define MAX8925_ALARM0_YEAR2 0x0f
45#define MAX8925_ALARM1_SEC 0x10
46#define MAX8925_ALARM1_MIN 0x11
47#define MAX8925_ALARM1_HOUR 0x12
48#define MAX8925_ALARM1_WEEKDAY 0x13
49#define MAX8925_ALARM1_DATE 0x14
50#define MAX8925_ALARM1_MON 0x15
51#define MAX8925_ALARM1_YEAR1 0x16
52#define MAX8925_ALARM1_YEAR2 0x17
53#define MAX8925_RTC_CNTL 0x1b
54#define MAX8925_RTC_STATUS 0x20
55
56#define TIME_NUM 8
57#define ALARM_1SEC (1 << 7)
58#define HOUR_12 (1 << 7)
59#define HOUR_AM_PM (1 << 5)
60#define ALARM0_IRQ (1 << 3)
61#define ALARM1_IRQ (1 << 2)
62#define ALARM0_STATUS (1 << 2)
63#define ALARM1_STATUS (1 << 1)
64
65
66struct max8925_rtc_info {
67 struct rtc_device *rtc_dev;
68 struct max8925_chip *chip;
69 struct i2c_client *rtc;
70 struct device *dev;
71};
72
73static irqreturn_t rtc_update_handler(int irq, void *data)
74{
75 struct max8925_rtc_info *info = (struct max8925_rtc_info *)data;
76
77 /* disable ALARM0 except for 1SEC alarm */
78 max8925_set_bits(info->rtc, MAX8925_ALARM0_CNTL, 0x7f, 0);
79 rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
80 return IRQ_HANDLED;
81}
82
83static int tm_calc(struct rtc_time *tm, unsigned char *buf, int len)
84{
85 if (len < TIME_NUM)
86 return -EINVAL;
87 tm->tm_year = (buf[RTC_YEAR2] >> 4) * 1000
88 + (buf[RTC_YEAR2] & 0xf) * 100
89 + (buf[RTC_YEAR1] >> 4) * 10
90 + (buf[RTC_YEAR1] & 0xf);
91 tm->tm_year -= 1900;
92 tm->tm_mon = ((buf[RTC_MONTH] >> 4) & 0x01) * 10
93 + (buf[RTC_MONTH] & 0x0f);
94 tm->tm_mday = ((buf[RTC_DATE] >> 4) & 0x03) * 10
95 + (buf[RTC_DATE] & 0x0f);
96 tm->tm_wday = buf[RTC_WEEKDAY] & 0x07;
97 if (buf[RTC_HOUR] & HOUR_12) {
98 tm->tm_hour = ((buf[RTC_HOUR] >> 4) & 0x1) * 10
99 + (buf[RTC_HOUR] & 0x0f);
100 if (buf[RTC_HOUR] & HOUR_AM_PM)
101 tm->tm_hour += 12;
102 } else
103 tm->tm_hour = ((buf[RTC_HOUR] >> 4) & 0x03) * 10
104 + (buf[RTC_HOUR] & 0x0f);
105 tm->tm_min = ((buf[RTC_MIN] >> 4) & 0x7) * 10
106 + (buf[RTC_MIN] & 0x0f);
107 tm->tm_sec = ((buf[RTC_SEC] >> 4) & 0x7) * 10
108 + (buf[RTC_SEC] & 0x0f);
109 return 0;
110}
111
112static int data_calc(unsigned char *buf, struct rtc_time *tm, int len)
113{
114 unsigned char high, low;
115
116 if (len < TIME_NUM)
117 return -EINVAL;
118
119 high = (tm->tm_year + 1900) / 1000;
120 low = (tm->tm_year + 1900) / 100;
121 low = low - high * 10;
122 buf[RTC_YEAR2] = (high << 4) + low;
123 high = (tm->tm_year + 1900) / 10;
124 low = tm->tm_year + 1900;
125 low = low - high * 10;
126 high = high - (high / 10) * 10;
127 buf[RTC_YEAR1] = (high << 4) + low;
128 high = tm->tm_mon / 10;
129 low = tm->tm_mon;
130 low = low - high * 10;
131 buf[RTC_MONTH] = (high << 4) + low;
132 high = tm->tm_mday / 10;
133 low = tm->tm_mday;
134 low = low - high * 10;
135 buf[RTC_DATE] = (high << 4) + low;
136 buf[RTC_WEEKDAY] = tm->tm_wday;
137 high = tm->tm_hour / 10;
138 low = tm->tm_hour;
139 low = low - high * 10;
140 buf[RTC_HOUR] = (high << 4) + low;
141 high = tm->tm_min / 10;
142 low = tm->tm_min;
143 low = low - high * 10;
144 buf[RTC_MIN] = (high << 4) + low;
145 high = tm->tm_sec / 10;
146 low = tm->tm_sec;
147 low = low - high * 10;
148 buf[RTC_SEC] = (high << 4) + low;
149 return 0;
150}
151
152static int max8925_rtc_read_time(struct device *dev, struct rtc_time *tm)
153{
154 struct max8925_rtc_info *info = dev_get_drvdata(dev);
155 unsigned char buf[TIME_NUM];
156 int ret;
157
158 ret = max8925_bulk_read(info->rtc, MAX8925_RTC_SEC, TIME_NUM, buf);
159 if (ret < 0)
160 goto out;
161 ret = tm_calc(tm, buf, TIME_NUM);
162out:
163 return ret;
164}
165
166static int max8925_rtc_set_time(struct device *dev, struct rtc_time *tm)
167{
168 struct max8925_rtc_info *info = dev_get_drvdata(dev);
169 unsigned char buf[TIME_NUM];
170 int ret;
171
172 ret = data_calc(buf, tm, TIME_NUM);
173 if (ret < 0)
174 goto out;
175 ret = max8925_bulk_write(info->rtc, MAX8925_RTC_SEC, TIME_NUM, buf);
176out:
177 return ret;
178}
179
180static int max8925_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
181{
182 struct max8925_rtc_info *info = dev_get_drvdata(dev);
183 unsigned char buf[TIME_NUM];
184 int ret;
185
186 ret = max8925_bulk_read(info->rtc, MAX8925_ALARM0_SEC, TIME_NUM, buf);
187 if (ret < 0)
188 goto out;
189 ret = tm_calc(&alrm->time, buf, TIME_NUM);
190 if (ret < 0)
191 goto out;
192 ret = max8925_reg_read(info->rtc, MAX8925_RTC_IRQ_MASK);
193 if (ret < 0)
194 goto out;
195 if ((ret & ALARM0_IRQ) == 0)
196 alrm->enabled = 1;
197 else
198 alrm->enabled = 0;
199 ret = max8925_reg_read(info->rtc, MAX8925_RTC_STATUS);
200 if (ret < 0)
201 goto out;
202 if (ret & ALARM0_STATUS)
203 alrm->pending = 1;
204 else
205 alrm->pending = 0;
206out:
207 return ret;
208}
209
210static int max8925_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
211{
212 struct max8925_rtc_info *info = dev_get_drvdata(dev);
213 unsigned char buf[TIME_NUM];
214 int ret;
215
216 ret = data_calc(buf, &alrm->time, TIME_NUM);
217 if (ret < 0)
218 goto out;
219 ret = max8925_bulk_write(info->rtc, MAX8925_ALARM0_SEC, TIME_NUM, buf);
220 if (ret < 0)
221 goto out;
222 /* only enable alarm on year/month/day/hour/min/sec */
223 ret = max8925_reg_write(info->rtc, MAX8925_ALARM0_CNTL, 0x77);
224 if (ret < 0)
225 goto out;
226out:
227 return ret;
228}
229
230static const struct rtc_class_ops max8925_rtc_ops = {
231 .read_time = max8925_rtc_read_time,
232 .set_time = max8925_rtc_set_time,
233 .read_alarm = max8925_rtc_read_alarm,
234 .set_alarm = max8925_rtc_set_alarm,
235};
236
237static int __devinit max8925_rtc_probe(struct platform_device *pdev)
238{
239 struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
240 struct max8925_rtc_info *info;
241 int irq, ret;
242
243 info = kzalloc(sizeof(struct max8925_rtc_info), GFP_KERNEL);
244 if (!info)
245 return -ENOMEM;
246 info->chip = chip;
247 info->rtc = chip->rtc;
248 info->dev = &pdev->dev;
249 irq = chip->irq_base + MAX8925_IRQ_RTC_ALARM0;
250
251 ret = request_threaded_irq(irq, NULL, rtc_update_handler,
252 IRQF_ONESHOT, "rtc-alarm0", info);
253 if (ret < 0) {
254 dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
255 irq, ret);
256 goto out_irq;
257 }
258
259 info->rtc_dev = rtc_device_register("max8925-rtc", &pdev->dev,
260 &max8925_rtc_ops, THIS_MODULE);
261 ret = PTR_ERR(info->rtc_dev);
262 if (IS_ERR(info->rtc_dev)) {
263 dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
264 goto out_rtc;
265 }
266
267 dev_set_drvdata(&pdev->dev, info);
268 platform_set_drvdata(pdev, info);
269
270 return 0;
271out_rtc:
272 free_irq(chip->irq_base + MAX8925_IRQ_RTC_ALARM0, info);
273out_irq:
274 kfree(info);
275 return ret;
276}
277
278static int __devexit max8925_rtc_remove(struct platform_device *pdev)
279{
280 struct max8925_rtc_info *info = platform_get_drvdata(pdev);
281
282 if (info) {
283 free_irq(info->chip->irq_base + MAX8925_IRQ_RTC_ALARM0, info);
284 rtc_device_unregister(info->rtc_dev);
285 kfree(info);
286 }
287 return 0;
288}
289
290static struct platform_driver max8925_rtc_driver = {
291 .driver = {
292 .name = "max8925-rtc",
293 .owner = THIS_MODULE,
294 },
295 .probe = max8925_rtc_probe,
296 .remove = __devexit_p(max8925_rtc_remove),
297};
298
299static int __init max8925_rtc_init(void)
300{
301 return platform_driver_register(&max8925_rtc_driver);
302}
303module_init(max8925_rtc_init);
304
305static void __exit max8925_rtc_exit(void)
306{
307 platform_driver_unregister(&max8925_rtc_driver);
308}
309module_exit(max8925_rtc_exit);
310
311MODULE_DESCRIPTION("Maxim MAX8925 RTC driver");
312MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
313MODULE_LICENSE("GPL");
314
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-13 17:52:39 -0500