Version:  2.0.40 2.2.26 2.4.37 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8

Linux/drivers/rtc/rtc-da9052.c

  1 /*
  2  * Real time clock driver for DA9052
  3  *
  4  * Copyright(c) 2012 Dialog Semiconductor Ltd.
  5  *
  6  * Author: Dajun Dajun Chen <dajun.chen@diasemi.com>
  7  *
  8  * This program is free software; you can redistribute it and/or modify
  9  * it under the terms of the GNU General Public License as published by
 10  * the Free Software Foundation; either version 2 of the License, or
 11  * (at your option) any later version.
 12  *
 13  */
 14 
 15 #include <linux/module.h>
 16 #include <linux/platform_device.h>
 17 #include <linux/rtc.h>
 18 #include <linux/err.h>
 19 #include <linux/delay.h>
 20 
 21 #include <linux/mfd/da9052/da9052.h>
 22 #include <linux/mfd/da9052/reg.h>
 23 
 24 #define rtc_err(rtc, fmt, ...) \
 25                 dev_err(rtc->da9052->dev, "%s: " fmt, __func__, ##__VA_ARGS__)
 26 
 27 #define DA9052_GET_TIME_RETRIES 5
 28 
 29 struct da9052_rtc {
 30         struct rtc_device *rtc;
 31         struct da9052 *da9052;
 32 };
 33 
 34 static int da9052_rtc_enable_alarm(struct da9052_rtc *rtc, bool enable)
 35 {
 36         int ret;
 37         if (enable) {
 38                 ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,
 39                                 DA9052_ALARM_Y_ALARM_ON|DA9052_ALARM_Y_TICK_ON,
 40                                 DA9052_ALARM_Y_ALARM_ON);
 41                 if (ret != 0)
 42                         rtc_err(rtc, "Failed to enable ALM: %d\n", ret);
 43         } else {
 44                 ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,
 45                         DA9052_ALARM_Y_ALARM_ON|DA9052_ALARM_Y_TICK_ON, 0);
 46                 if (ret != 0)
 47                         rtc_err(rtc, "Write error: %d\n", ret);
 48         }
 49         return ret;
 50 }
 51 
 52 static irqreturn_t da9052_rtc_irq(int irq, void *data)
 53 {
 54         struct da9052_rtc *rtc = data;
 55 
 56         rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);
 57 
 58         return IRQ_HANDLED;
 59 }
 60 
 61 static int da9052_read_alarm(struct da9052_rtc *rtc, struct rtc_time *rtc_tm)
 62 {
 63         int ret;
 64         uint8_t v[2][5];
 65         int idx = 1;
 66         int timeout = DA9052_GET_TIME_RETRIES;
 67 
 68         ret = da9052_group_read(rtc->da9052, DA9052_ALARM_MI_REG, 5, &v[0][0]);
 69         if (ret) {
 70                 rtc_err(rtc, "Failed to group read ALM: %d\n", ret);
 71                 return ret;
 72         }
 73 
 74         do {
 75                 ret = da9052_group_read(rtc->da9052,
 76                                         DA9052_ALARM_MI_REG, 5, &v[idx][0]);
 77                 if (ret) {
 78                         rtc_err(rtc, "Failed to group read ALM: %d\n", ret);
 79                         return ret;
 80                 }
 81 
 82                 if (memcmp(&v[0][0], &v[1][0], 5) == 0) {
 83                         rtc_tm->tm_year = (v[0][4] & DA9052_RTC_YEAR) + 100;
 84                         rtc_tm->tm_mon  = (v[0][3] & DA9052_RTC_MONTH) - 1;
 85                         rtc_tm->tm_mday = v[0][2] & DA9052_RTC_DAY;
 86                         rtc_tm->tm_hour = v[0][1] & DA9052_RTC_HOUR;
 87                         rtc_tm->tm_min  = v[0][0] & DA9052_RTC_MIN;
 88                         rtc_tm->tm_sec = 0;
 89 
 90                         ret = rtc_valid_tm(rtc_tm);
 91                         return ret;
 92                 }
 93 
 94                 idx = (1-idx);
 95                 msleep(20);
 96 
 97         } while (timeout--);
 98 
 99         rtc_err(rtc, "Timed out reading alarm time\n");
100 
101         return -EIO;
102 }
103 
104 static int da9052_set_alarm(struct da9052_rtc *rtc, struct rtc_time *rtc_tm)
105 {
106         struct da9052 *da9052 = rtc->da9052;
107         unsigned long alm_time;
108         int ret;
109         uint8_t v[3];
110 
111         ret = rtc_tm_to_time(rtc_tm, &alm_time);
112         if (ret != 0)
113                 return ret;
114 
115         if (rtc_tm->tm_sec > 0) {
116                 alm_time += 60 - rtc_tm->tm_sec;
117                 rtc_time_to_tm(alm_time, rtc_tm);
118         }
119         BUG_ON(rtc_tm->tm_sec); /* it will cause repeated irqs if not zero */
120 
121         rtc_tm->tm_year -= 100;
122         rtc_tm->tm_mon += 1;
123 
124         ret = da9052_reg_update(da9052, DA9052_ALARM_MI_REG,
125                                 DA9052_RTC_MIN, rtc_tm->tm_min);
126         if (ret != 0) {
127                 rtc_err(rtc, "Failed to write ALRM MIN: %d\n", ret);
128                 return ret;
129         }
130 
131         v[0] = rtc_tm->tm_hour;
132         v[1] = rtc_tm->tm_mday;
133         v[2] = rtc_tm->tm_mon;
134 
135         ret = da9052_group_write(da9052, DA9052_ALARM_H_REG, 3, v);
136         if (ret < 0)
137                 return ret;
138 
139         ret = da9052_reg_update(da9052, DA9052_ALARM_Y_REG,
140                                 DA9052_RTC_YEAR, rtc_tm->tm_year);
141         if (ret != 0)
142                 rtc_err(rtc, "Failed to write ALRM YEAR: %d\n", ret);
143 
144         return ret;
145 }
146 
147 static int da9052_rtc_get_alarm_status(struct da9052_rtc *rtc)
148 {
149         int ret;
150 
151         ret = da9052_reg_read(rtc->da9052, DA9052_ALARM_Y_REG);
152         if (ret < 0) {
153                 rtc_err(rtc, "Failed to read ALM: %d\n", ret);
154                 return ret;
155         }
156 
157         return !!(ret&DA9052_ALARM_Y_ALARM_ON);
158 }
159 
160 static int da9052_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm)
161 {
162         struct da9052_rtc *rtc = dev_get_drvdata(dev);
163         int ret;
164         uint8_t v[2][6];
165         int idx = 1;
166         int timeout = DA9052_GET_TIME_RETRIES;
167 
168         ret = da9052_group_read(rtc->da9052, DA9052_COUNT_S_REG, 6, &v[0][0]);
169         if (ret) {
170                 rtc_err(rtc, "Failed to read RTC time : %d\n", ret);
171                 return ret;
172         }
173 
174         do {
175                 ret = da9052_group_read(rtc->da9052,
176                                         DA9052_COUNT_S_REG, 6, &v[idx][0]);
177                 if (ret) {
178                         rtc_err(rtc, "Failed to read RTC time : %d\n", ret);
179                         return ret;
180                 }
181 
182                 if (memcmp(&v[0][0], &v[1][0], 6) == 0) {
183                         rtc_tm->tm_year = (v[0][5] & DA9052_RTC_YEAR) + 100;
184                         rtc_tm->tm_mon  = (v[0][4] & DA9052_RTC_MONTH) - 1;
185                         rtc_tm->tm_mday = v[0][3] & DA9052_RTC_DAY;
186                         rtc_tm->tm_hour = v[0][2] & DA9052_RTC_HOUR;
187                         rtc_tm->tm_min  = v[0][1] & DA9052_RTC_MIN;
188                         rtc_tm->tm_sec  = v[0][0] & DA9052_RTC_SEC;
189 
190                         ret = rtc_valid_tm(rtc_tm);
191                         return ret;
192                 }
193 
194                 idx = (1-idx);
195                 msleep(20);
196 
197         } while (timeout--);
198 
199         rtc_err(rtc, "Timed out reading time\n");
200 
201         return -EIO;
202 }
203 
204 static int da9052_rtc_set_time(struct device *dev, struct rtc_time *tm)
205 {
206         struct da9052_rtc *rtc;
207         uint8_t v[6];
208         int ret;
209 
210         /* DA9052 only has 6 bits for year - to represent 2000-2063 */
211         if ((tm->tm_year < 100) || (tm->tm_year > 163))
212                 return -EINVAL;
213 
214         rtc = dev_get_drvdata(dev);
215 
216         v[0] = tm->tm_sec;
217         v[1] = tm->tm_min;
218         v[2] = tm->tm_hour;
219         v[3] = tm->tm_mday;
220         v[4] = tm->tm_mon + 1;
221         v[5] = tm->tm_year - 100;
222 
223         ret = da9052_group_write(rtc->da9052, DA9052_COUNT_S_REG, 6, v);
224         if (ret < 0)
225                 rtc_err(rtc, "failed to set RTC time: %d\n", ret);
226         return ret;
227 }
228 
229 static int da9052_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
230 {
231         int ret;
232         struct rtc_time *tm = &alrm->time;
233         struct da9052_rtc *rtc = dev_get_drvdata(dev);
234 
235         ret = da9052_read_alarm(rtc, tm);
236         if (ret < 0) {
237                 rtc_err(rtc, "failed to read RTC alarm: %d\n", ret);
238                 return ret;
239         }
240 
241         alrm->enabled = da9052_rtc_get_alarm_status(rtc);
242         return 0;
243 }
244 
245 static int da9052_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
246 {
247         int ret;
248         struct rtc_time *tm = &alrm->time;
249         struct da9052_rtc *rtc = dev_get_drvdata(dev);
250 
251         /* DA9052 only has 6 bits for year - to represent 2000-2063 */
252         if ((tm->tm_year < 100) || (tm->tm_year > 163))
253                 return -EINVAL;
254 
255         ret = da9052_rtc_enable_alarm(rtc, 0);
256         if (ret < 0)
257                 return ret;
258 
259         ret = da9052_set_alarm(rtc, tm);
260         if (ret < 0)
261                 return ret;
262 
263         ret = da9052_rtc_enable_alarm(rtc, 1);
264         return ret;
265 }
266 
267 static int da9052_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
268 {
269         struct da9052_rtc *rtc = dev_get_drvdata(dev);
270 
271         return da9052_rtc_enable_alarm(rtc, enabled);
272 }
273 
274 static const struct rtc_class_ops da9052_rtc_ops = {
275         .read_time      = da9052_rtc_read_time,
276         .set_time       = da9052_rtc_set_time,
277         .read_alarm     = da9052_rtc_read_alarm,
278         .set_alarm      = da9052_rtc_set_alarm,
279         .alarm_irq_enable = da9052_rtc_alarm_irq_enable,
280 };
281 
282 static int da9052_rtc_probe(struct platform_device *pdev)
283 {
284         struct da9052_rtc *rtc;
285         int ret;
286 
287         rtc = devm_kzalloc(&pdev->dev, sizeof(struct da9052_rtc), GFP_KERNEL);
288         if (!rtc)
289                 return -ENOMEM;
290 
291         rtc->da9052 = dev_get_drvdata(pdev->dev.parent);
292         platform_set_drvdata(pdev, rtc);
293 
294         ret = da9052_reg_write(rtc->da9052, DA9052_BBAT_CONT_REG, 0xFE);
295         if (ret < 0) {
296                 rtc_err(rtc,
297                         "Failed to setup RTC battery charging: %d\n", ret);
298                 return ret;
299         }
300 
301         ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,
302                                 DA9052_ALARM_Y_TICK_ON, 0);
303         if (ret != 0)
304                 rtc_err(rtc, "Failed to disable TICKS: %d\n", ret);
305 
306         device_init_wakeup(&pdev->dev, true);
307         rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
308                                        &da9052_rtc_ops, THIS_MODULE);
309 
310         if (IS_ERR(rtc->rtc))
311                 return PTR_ERR(rtc->rtc);
312 
313         ret = da9052_request_irq(rtc->da9052, DA9052_IRQ_ALARM, "ALM",
314                                 da9052_rtc_irq, rtc);
315         if (ret != 0) {
316                 rtc_err(rtc, "irq registration failed: %d\n", ret);
317                 return ret;
318         }
319 
320         return 0;
321 }
322 
323 static struct platform_driver da9052_rtc_driver = {
324         .probe  = da9052_rtc_probe,
325         .driver = {
326                 .name   = "da9052-rtc",
327         },
328 };
329 
330 module_platform_driver(da9052_rtc_driver);
331 
332 MODULE_AUTHOR("Anthony Olech <Anthony.Olech@diasemi.com>");
333 MODULE_DESCRIPTION("RTC driver for Dialog DA9052 PMIC");
334 MODULE_LICENSE("GPL");
335 MODULE_ALIAS("platform:da9052-rtc");
336 

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds  •  Contact us