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path: root/drivers/rtc/rtc-max8925.c
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Diffstat (limited to 'drivers/rtc/rtc-max8925.c')
-rw-r--r--drivers/rtc/rtc-max8925.c315
1 files changed, 315 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-max8925.c b/drivers/rtc/rtc-max8925.c
new file mode 100644
index 000000000000..174036dda786
--- /dev/null
+++ b/drivers/rtc/rtc-max8925.c
@@ -0,0 +1,315 @@
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/slab.h>
15#include <linux/rtc.h>
16#include <linux/platform_device.h>
17#include <linux/mfd/max8925.h>
18
19enum {
20 RTC_SEC = 0,
21 RTC_MIN,
22 RTC_HOUR,
23 RTC_WEEKDAY,
24 RTC_DATE,
25 RTC_MONTH,
26 RTC_YEAR1,
27 RTC_YEAR2,
28};
29
30#define MAX8925_RTC_SEC 0x00
31#define MAX8925_RTC_MIN 0x01
32#define MAX8925_RTC_HOUR 0x02
33#define MAX8925_RTC_WEEKDAY 0x03
34#define MAX8925_RTC_DATE 0x04
35#define MAX8925_RTC_MONTH 0x05
36#define MAX8925_RTC_YEAR1 0x06
37#define MAX8925_RTC_YEAR2 0x07
38#define MAX8925_ALARM0_SEC 0x08
39#define MAX8925_ALARM0_MIN 0x09
40#define MAX8925_ALARM0_HOUR 0x0a
41#define MAX8925_ALARM0_WEEKDAY 0x0b
42#define MAX8925_ALARM0_DATE 0x0c
43#define MAX8925_ALARM0_MON 0x0d
44#define MAX8925_ALARM0_YEAR1 0x0e
45#define MAX8925_ALARM0_YEAR2 0x0f
46#define MAX8925_ALARM1_SEC 0x10
47#define MAX8925_ALARM1_MIN 0x11
48#define MAX8925_ALARM1_HOUR 0x12
49#define MAX8925_ALARM1_WEEKDAY 0x13
50#define MAX8925_ALARM1_DATE 0x14
51#define MAX8925_ALARM1_MON 0x15
52#define MAX8925_ALARM1_YEAR1 0x16
53#define MAX8925_ALARM1_YEAR2 0x17
54#define MAX8925_RTC_CNTL 0x1b
55#define MAX8925_RTC_STATUS 0x20
56
57#define TIME_NUM 8
58#define ALARM_1SEC (1 << 7)
59#define HOUR_12 (1 << 7)
60#define HOUR_AM_PM (1 << 5)
61#define ALARM0_IRQ (1 << 3)
62#define ALARM1_IRQ (1 << 2)
63#define ALARM0_STATUS (1 << 2)
64#define ALARM1_STATUS (1 << 1)
65
66
67struct max8925_rtc_info {
68 struct rtc_device *rtc_dev;
69 struct max8925_chip *chip;
70 struct i2c_client *rtc;
71 struct device *dev;
72};
73
74static irqreturn_t rtc_update_handler(int irq, void *data)
75{
76 struct max8925_rtc_info *info = (struct max8925_rtc_info *)data;
77
78 /* disable ALARM0 except for 1SEC alarm */
79 max8925_set_bits(info->rtc, MAX8925_ALARM0_CNTL, 0x7f, 0);
80 rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
81 return IRQ_HANDLED;
82}
83
84static int tm_calc(struct rtc_time *tm, unsigned char *buf, int len)
85{
86 if (len < TIME_NUM)
87 return -EINVAL;
88 tm->tm_year = (buf[RTC_YEAR2] >> 4) * 1000
89 + (buf[RTC_YEAR2] & 0xf) * 100
90 + (buf[RTC_YEAR1] >> 4) * 10
91 + (buf[RTC_YEAR1] & 0xf);
92 tm->tm_year -= 1900;
93 tm->tm_mon = ((buf[RTC_MONTH] >> 4) & 0x01) * 10
94 + (buf[RTC_MONTH] & 0x0f);
95 tm->tm_mday = ((buf[RTC_DATE] >> 4) & 0x03) * 10
96 + (buf[RTC_DATE] & 0x0f);
97 tm->tm_wday = buf[RTC_WEEKDAY] & 0x07;
98 if (buf[RTC_HOUR] & HOUR_12) {
99 tm->tm_hour = ((buf[RTC_HOUR] >> 4) & 0x1) * 10
100 + (buf[RTC_HOUR] & 0x0f);
101 if (buf[RTC_HOUR] & HOUR_AM_PM)
102 tm->tm_hour += 12;
103 } else
104 tm->tm_hour = ((buf[RTC_HOUR] >> 4) & 0x03) * 10
105 + (buf[RTC_HOUR] & 0x0f);
106 tm->tm_min = ((buf[RTC_MIN] >> 4) & 0x7) * 10
107 + (buf[RTC_MIN] & 0x0f);
108 tm->tm_sec = ((buf[RTC_SEC] >> 4) & 0x7) * 10
109 + (buf[RTC_SEC] & 0x0f);
110 return 0;
111}
112
113static int data_calc(unsigned char *buf, struct rtc_time *tm, int len)
114{
115 unsigned char high, low;
116
117 if (len < TIME_NUM)
118 return -EINVAL;
119
120 high = (tm->tm_year + 1900) / 1000;
121 low = (tm->tm_year + 1900) / 100;
122 low = low - high * 10;
123 buf[RTC_YEAR2] = (high << 4) + low;
124 high = (tm->tm_year + 1900) / 10;
125 low = tm->tm_year + 1900;
126 low = low - high * 10;
127 high = high - (high / 10) * 10;
128 buf[RTC_YEAR1] = (high << 4) + low;
129 high = tm->tm_mon / 10;
130 low = tm->tm_mon;
131 low = low - high * 10;
132 buf[RTC_MONTH] = (high << 4) + low;
133 high = tm->tm_mday / 10;
134 low = tm->tm_mday;
135 low = low - high * 10;
136 buf[RTC_DATE] = (high << 4) + low;
137 buf[RTC_WEEKDAY] = tm->tm_wday;
138 high = tm->tm_hour / 10;
139 low = tm->tm_hour;
140 low = low - high * 10;
141 buf[RTC_HOUR] = (high << 4) + low;
142 high = tm->tm_min / 10;
143 low = tm->tm_min;
144 low = low - high * 10;
145 buf[RTC_MIN] = (high << 4) + low;
146 high = tm->tm_sec / 10;
147 low = tm->tm_sec;
148 low = low - high * 10;
149 buf[RTC_SEC] = (high << 4) + low;
150 return 0;
151}
152
153static int max8925_rtc_read_time(struct device *dev, struct rtc_time *tm)
154{
155 struct max8925_rtc_info *info = dev_get_drvdata(dev);
156 unsigned char buf[TIME_NUM];
157 int ret;
158
159 ret = max8925_bulk_read(info->rtc, MAX8925_RTC_SEC, TIME_NUM, buf);
160 if (ret < 0)
161 goto out;
162 ret = tm_calc(tm, buf, TIME_NUM);
163out:
164 return ret;
165}
166
167static int max8925_rtc_set_time(struct device *dev, struct rtc_time *tm)
168{
169 struct max8925_rtc_info *info = dev_get_drvdata(dev);
170 unsigned char buf[TIME_NUM];
171 int ret;
172
173 ret = data_calc(buf, tm, TIME_NUM);
174 if (ret < 0)
175 goto out;
176 ret = max8925_bulk_write(info->rtc, MAX8925_RTC_SEC, TIME_NUM, buf);
177out:
178 return ret;
179}
180
181static int max8925_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
182{
183 struct max8925_rtc_info *info = dev_get_drvdata(dev);
184 unsigned char buf[TIME_NUM];
185 int ret;
186
187 ret = max8925_bulk_read(info->rtc, MAX8925_ALARM0_SEC, TIME_NUM, buf);
188 if (ret < 0)
189 goto out;
190 ret = tm_calc(&alrm->time, buf, TIME_NUM);
191 if (ret < 0)
192 goto out;
193 ret = max8925_reg_read(info->rtc, MAX8925_RTC_IRQ_MASK);
194 if (ret < 0)
195 goto out;
196 if ((ret & ALARM0_IRQ) == 0)
197 alrm->enabled = 1;
198 else
199 alrm->enabled = 0;
200 ret = max8925_reg_read(info->rtc, MAX8925_RTC_STATUS);
201 if (ret < 0)
202 goto out;
203 if (ret & ALARM0_STATUS)
204 alrm->pending = 1;
205 else
206 alrm->pending = 0;
207out:
208 return ret;
209}
210
211static int max8925_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
212{
213 struct max8925_rtc_info *info = dev_get_drvdata(dev);
214 unsigned char buf[TIME_NUM];
215 int ret;
216
217 ret = data_calc(buf, &alrm->time, TIME_NUM);
218 if (ret < 0)
219 goto out;
220 ret = max8925_bulk_write(info->rtc, MAX8925_ALARM0_SEC, TIME_NUM, buf);
221 if (ret < 0)
222 goto out;
223 /* only enable alarm on year/month/day/hour/min/sec */
224 ret = max8925_reg_write(info->rtc, MAX8925_ALARM0_CNTL, 0x77);
225 if (ret < 0)
226 goto out;
227out:
228 return ret;
229}
230
231static const struct rtc_class_ops max8925_rtc_ops = {
232 .read_time = max8925_rtc_read_time,
233 .set_time = max8925_rtc_set_time,
234 .read_alarm = max8925_rtc_read_alarm,
235 .set_alarm = max8925_rtc_set_alarm,
236};
237
238static int __devinit max8925_rtc_probe(struct platform_device *pdev)
239{
240 struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
241 struct max8925_rtc_info *info;
242 int irq, ret;
243
244 info = kzalloc(sizeof(struct max8925_rtc_info), GFP_KERNEL);
245 if (!info)
246 return -ENOMEM;
247 info->chip = chip;
248 info->rtc = chip->rtc;
249 info->dev = &pdev->dev;
250 irq = chip->irq_base + MAX8925_IRQ_RTC_ALARM0;
251
252 ret = request_threaded_irq(irq, NULL, rtc_update_handler,
253 IRQF_ONESHOT, "rtc-alarm0", info);
254 if (ret < 0) {
255 dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
256 irq, ret);
257 goto out_irq;
258 }
259
260 info->rtc_dev = rtc_device_register("max8925-rtc", &pdev->dev,
261 &max8925_rtc_ops, THIS_MODULE);
262 ret = PTR_ERR(info->rtc_dev);
263 if (IS_ERR(info->rtc_dev)) {
264 dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
265 goto out_rtc;
266 }
267
268 dev_set_drvdata(&pdev->dev, info);
269 platform_set_drvdata(pdev, info);
270
271 return 0;
272out_rtc:
273 free_irq(chip->irq_base + MAX8925_IRQ_RTC_ALARM0, info);
274out_irq:
275 kfree(info);
276 return ret;
277}
278
279static int __devexit max8925_rtc_remove(struct platform_device *pdev)
280{
281 struct max8925_rtc_info *info = platform_get_drvdata(pdev);
282
283 if (info) {
284 free_irq(info->chip->irq_base + MAX8925_IRQ_RTC_ALARM0, info);
285 rtc_device_unregister(info->rtc_dev);
286 kfree(info);
287 }
288 return 0;
289}
290
291static struct platform_driver max8925_rtc_driver = {
292 .driver = {
293 .name = "max8925-rtc",
294 .owner = THIS_MODULE,
295 },
296 .probe = max8925_rtc_probe,
297 .remove = __devexit_p(max8925_rtc_remove),
298};
299
300static int __init max8925_rtc_init(void)
301{
302 return platform_driver_register(&max8925_rtc_driver);
303}
304module_init(max8925_rtc_init);
305
306static void __exit max8925_rtc_exit(void)
307{
308 platform_driver_unregister(&max8925_rtc_driver);
309}
310module_exit(max8925_rtc_exit);
311
312MODULE_DESCRIPTION("Maxim MAX8925 RTC driver");
313MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
314MODULE_LICENSE("GPL");
315
generated by cgit v1.2.2 (git 2.25.0) at 2025-12-08 10:31:29 -0500