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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 int irq;
73};
74
75static irqreturn_t rtc_update_handler(int irq, void *data)
76{
77 struct max8925_rtc_info *info = (struct max8925_rtc_info *)data;
78
79
80 max8925_set_bits(info->rtc, MAX8925_ALARM0_CNTL, 0x7f, 0);
81 rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
82 return IRQ_HANDLED;
83}
84
85static int tm_calc(struct rtc_time *tm, unsigned char *buf, int len)
86{
87 if (len < TIME_NUM)
88 return -EINVAL;
89 tm->tm_year = (buf[RTC_YEAR2] >> 4) * 1000
90 + (buf[RTC_YEAR2] & 0xf) * 100
91 + (buf[RTC_YEAR1] >> 4) * 10
92 + (buf[RTC_YEAR1] & 0xf);
93 tm->tm_year -= 1900;
94 tm->tm_mon = ((buf[RTC_MONTH] >> 4) & 0x01) * 10
95 + (buf[RTC_MONTH] & 0x0f);
96 tm->tm_mday = ((buf[RTC_DATE] >> 4) & 0x03) * 10
97 + (buf[RTC_DATE] & 0x0f);
98 tm->tm_wday = buf[RTC_WEEKDAY] & 0x07;
99 if (buf[RTC_HOUR] & HOUR_12) {
100 tm->tm_hour = ((buf[RTC_HOUR] >> 4) & 0x1) * 10
101 + (buf[RTC_HOUR] & 0x0f);
102 if (buf[RTC_HOUR] & HOUR_AM_PM)
103 tm->tm_hour += 12;
104 } else
105 tm->tm_hour = ((buf[RTC_HOUR] >> 4) & 0x03) * 10
106 + (buf[RTC_HOUR] & 0x0f);
107 tm->tm_min = ((buf[RTC_MIN] >> 4) & 0x7) * 10
108 + (buf[RTC_MIN] & 0x0f);
109 tm->tm_sec = ((buf[RTC_SEC] >> 4) & 0x7) * 10
110 + (buf[RTC_SEC] & 0x0f);
111 return 0;
112}
113
114static int data_calc(unsigned char *buf, struct rtc_time *tm, int len)
115{
116 unsigned char high, low;
117
118 if (len < TIME_NUM)
119 return -EINVAL;
120
121 high = (tm->tm_year + 1900) / 1000;
122 low = (tm->tm_year + 1900) / 100;
123 low = low - high * 10;
124 buf[RTC_YEAR2] = (high << 4) + low;
125 high = (tm->tm_year + 1900) / 10;
126 low = tm->tm_year + 1900;
127 low = low - high * 10;
128 high = high - (high / 10) * 10;
129 buf[RTC_YEAR1] = (high << 4) + low;
130 high = tm->tm_mon / 10;
131 low = tm->tm_mon;
132 low = low - high * 10;
133 buf[RTC_MONTH] = (high << 4) + low;
134 high = tm->tm_mday / 10;
135 low = tm->tm_mday;
136 low = low - high * 10;
137 buf[RTC_DATE] = (high << 4) + low;
138 buf[RTC_WEEKDAY] = tm->tm_wday;
139 high = tm->tm_hour / 10;
140 low = tm->tm_hour;
141 low = low - high * 10;
142 buf[RTC_HOUR] = (high << 4) + low;
143 high = tm->tm_min / 10;
144 low = tm->tm_min;
145 low = low - high * 10;
146 buf[RTC_MIN] = (high << 4) + low;
147 high = tm->tm_sec / 10;
148 low = tm->tm_sec;
149 low = low - high * 10;
150 buf[RTC_SEC] = (high << 4) + low;
151 return 0;
152}
153
154static int max8925_rtc_read_time(struct device *dev, struct rtc_time *tm)
155{
156 struct max8925_rtc_info *info = dev_get_drvdata(dev);
157 unsigned char buf[TIME_NUM];
158 int ret;
159
160 ret = max8925_bulk_read(info->rtc, MAX8925_RTC_SEC, TIME_NUM, buf);
161 if (ret < 0)
162 goto out;
163 ret = tm_calc(tm, buf, TIME_NUM);
164out:
165 return ret;
166}
167
168static int max8925_rtc_set_time(struct device *dev, struct rtc_time *tm)
169{
170 struct max8925_rtc_info *info = dev_get_drvdata(dev);
171 unsigned char buf[TIME_NUM];
172 int ret;
173
174 ret = data_calc(buf, tm, TIME_NUM);
175 if (ret < 0)
176 goto out;
177 ret = max8925_bulk_write(info->rtc, MAX8925_RTC_SEC, TIME_NUM, buf);
178out:
179 return ret;
180}
181
182static int max8925_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
183{
184 struct max8925_rtc_info *info = dev_get_drvdata(dev);
185 unsigned char buf[TIME_NUM];
186 int ret;
187
188 ret = max8925_bulk_read(info->rtc, MAX8925_ALARM0_SEC, TIME_NUM, buf);
189 if (ret < 0)
190 goto out;
191 ret = tm_calc(&alrm->time, buf, TIME_NUM);
192 if (ret < 0)
193 goto out;
194 ret = max8925_reg_read(info->rtc, MAX8925_RTC_IRQ_MASK);
195 if (ret < 0)
196 goto out;
197 if (ret & ALARM0_IRQ) {
198 alrm->enabled = 0;
199 } else {
200 ret = max8925_reg_read(info->rtc, MAX8925_ALARM0_CNTL);
201 if (ret < 0)
202 goto out;
203 if (!ret)
204 alrm->enabled = 0;
205 else
206 alrm->enabled = 1;
207 }
208 ret = max8925_reg_read(info->rtc, MAX8925_RTC_STATUS);
209 if (ret < 0)
210 goto out;
211 if (ret & ALARM0_STATUS)
212 alrm->pending = 1;
213 else
214 alrm->pending = 0;
215 return 0;
216out:
217 return ret;
218}
219
220static int max8925_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
221{
222 struct max8925_rtc_info *info = dev_get_drvdata(dev);
223 unsigned char buf[TIME_NUM];
224 int ret;
225
226 ret = data_calc(buf, &alrm->time, TIME_NUM);
227 if (ret < 0)
228 goto out;
229 ret = max8925_bulk_write(info->rtc, MAX8925_ALARM0_SEC, TIME_NUM, buf);
230 if (ret < 0)
231 goto out;
232 if (alrm->enabled)
233
234 ret = max8925_reg_write(info->rtc, MAX8925_ALARM0_CNTL, 0x77);
235 else
236 ret = max8925_reg_write(info->rtc, MAX8925_ALARM0_CNTL, 0x0);
237out:
238 return ret;
239}
240
241static const struct rtc_class_ops max8925_rtc_ops = {
242 .read_time = max8925_rtc_read_time,
243 .set_time = max8925_rtc_set_time,
244 .read_alarm = max8925_rtc_read_alarm,
245 .set_alarm = max8925_rtc_set_alarm,
246};
247
248static int max8925_rtc_probe(struct platform_device *pdev)
249{
250 struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
251 struct max8925_rtc_info *info;
252 int ret;
253
254 info = devm_kzalloc(&pdev->dev, sizeof(struct max8925_rtc_info),
255 GFP_KERNEL);
256 if (!info)
257 return -ENOMEM;
258 info->chip = chip;
259 info->rtc = chip->rtc;
260 info->dev = &pdev->dev;
261 info->irq = platform_get_irq(pdev, 0);
262
263 ret = devm_request_threaded_irq(&pdev->dev, info->irq, NULL,
264 rtc_update_handler, IRQF_ONESHOT,
265 "rtc-alarm0", info);
266 if (ret < 0) {
267 dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
268 info->irq, ret);
269 return ret;
270 }
271
272 dev_set_drvdata(&pdev->dev, info);
273
274 platform_set_drvdata(pdev, info);
275
276 device_init_wakeup(&pdev->dev, 1);
277
278 info->rtc_dev = devm_rtc_device_register(&pdev->dev, "max8925-rtc",
279 &max8925_rtc_ops, THIS_MODULE);
280 ret = PTR_ERR(info->rtc_dev);
281 if (IS_ERR(info->rtc_dev)) {
282 dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
283 return ret;
284 }
285
286 return 0;
287}
288
289#ifdef CONFIG_PM_SLEEP
290static int max8925_rtc_suspend(struct device *dev)
291{
292 struct platform_device *pdev = to_platform_device(dev);
293 struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
294
295 if (device_may_wakeup(dev))
296 chip->wakeup_flag |= 1 << MAX8925_IRQ_RTC_ALARM0;
297 return 0;
298}
299static int max8925_rtc_resume(struct device *dev)
300{
301 struct platform_device *pdev = to_platform_device(dev);
302 struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
303
304 if (device_may_wakeup(dev))
305 chip->wakeup_flag &= ~(1 << MAX8925_IRQ_RTC_ALARM0);
306 return 0;
307}
308#endif
309
310static SIMPLE_DEV_PM_OPS(max8925_rtc_pm_ops, max8925_rtc_suspend, max8925_rtc_resume);
311
312static struct platform_driver max8925_rtc_driver = {
313 .driver = {
314 .name = "max8925-rtc",
315 .pm = &max8925_rtc_pm_ops,
316 },
317 .probe = max8925_rtc_probe,
318};
319
320module_platform_driver(max8925_rtc_driver);
321
322MODULE_DESCRIPTION("Maxim MAX8925 RTC driver");
323MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
324MODULE_LICENSE("GPL");
325
326
