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
  20 #include <linux/mfd/da9052/da9052.h>
  21 #include <linux/mfd/da9052/reg.h>
  22
  23 #define rtc_err(rtc, fmt, ...) \
  24                 dev_err(rtc->da9052->dev, "%s: " fmt, __func__, ##__VA_ARGS__)
  25
  26 struct da9052_rtc {
  27         struct rtc_device *rtc;
  28         struct da9052 *da9052;
  29 };
  30
  31 static int da9052_rtc_enable_alarm(struct da9052_rtc *rtc, bool enable)
  32 {
  33         int ret;
  34         if (enable) {
  35                 ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,
  36                                 DA9052_ALARM_Y_ALARM_ON|DA9052_ALARM_Y_TICK_ON,
  37                                 DA9052_ALARM_Y_ALARM_ON);
  38                 if (ret != 0)
  39                         rtc_err(rtc, "Failed to enable ALM: %d\n", ret);
  40         } else {
  41                 ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,
  42                         DA9052_ALARM_Y_ALARM_ON|DA9052_ALARM_Y_TICK_ON, 0);
  43                 if (ret != 0)
  44                         rtc_err(rtc, "Write error: %d\n", ret);
  45         }
  46         return ret;
  47 }
  48
  49 static irqreturn_t da9052_rtc_irq(int irq, void *data)
  50 {
  51         struct da9052_rtc *rtc = data;
  52
  53         rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);
  54
  55         return IRQ_HANDLED;
  56 }
  57
  58 static int da9052_read_alarm(struct da9052_rtc *rtc, struct rtc_time *rtc_tm)
  59 {
  60         int ret;
  61         uint8_t v[5];
  62
  63         ret = da9052_group_read(rtc->da9052, DA9052_ALARM_MI_REG, 5, v);
  64         if (ret != 0) {
  65                 rtc_err(rtc, "Failed to group read ALM: %d\n", ret);
  66                 return ret;
  67         }
  68
  69         rtc_tm->tm_year = (v[4] & DA9052_RTC_YEAR) + 100;
  70         rtc_tm->tm_mon  = (v[3] & DA9052_RTC_MONTH) - 1;
  71         rtc_tm->tm_mday = v[2] & DA9052_RTC_DAY;
  72         rtc_tm->tm_hour = v[1] & DA9052_RTC_HOUR;
  73         rtc_tm->tm_min  = v[0] & DA9052_RTC_MIN;
  74
  75         ret = rtc_valid_tm(rtc_tm);
  76         return ret;
  77 }
  78
  79 static int da9052_set_alarm(struct da9052_rtc *rtc, struct rtc_time *rtc_tm)
  80 {
  81         struct da9052 *da9052 = rtc->da9052;
  82         unsigned long alm_time;
  83         int ret;
  84         uint8_t v[3];
  85
  86         ret = rtc_tm_to_time(rtc_tm, &alm_time);
  87         if (ret != 0)
  88                 return ret;
  89
  90         if (rtc_tm->tm_sec > 0) {
  91                 alm_time += 60 - rtc_tm->tm_sec;
  92                 rtc_time_to_tm(alm_time, rtc_tm);
  93         }
  94         BUG_ON(rtc_tm->tm_sec); /* it will cause repeated irqs if not zero */
  95
  96         rtc_tm->tm_year -= 100;
  97         rtc_tm->tm_mon += 1;
  98
  99         ret = da9052_reg_update(da9052, DA9052_ALARM_MI_REG,
 100                                 DA9052_RTC_MIN, rtc_tm->tm_min);
 101         if (ret != 0) {
 102                 rtc_err(rtc, "Failed to write ALRM MIN: %d\n", ret);
 103                 return ret;
 104         }
 105
 106         v[0] = rtc_tm->tm_hour;
 107         v[1] = rtc_tm->tm_mday;
 108         v[2] = rtc_tm->tm_mon;
 109
 110         ret = da9052_group_write(da9052, DA9052_ALARM_H_REG, 3, v);
 111         if (ret < 0)
 112                 return ret;
 113
 114         ret = da9052_reg_update(da9052, DA9052_ALARM_Y_REG,
 115                                 DA9052_RTC_YEAR, rtc_tm->tm_year);
 116         if (ret != 0)
 117                 rtc_err(rtc, "Failed to write ALRM YEAR: %d\n", ret);
 118
 119         return ret;
 120 }
 121
 122 static int da9052_rtc_get_alarm_status(struct da9052_rtc *rtc)
 123 {
 124         int ret;
 125
 126         ret = da9052_reg_read(rtc->da9052, DA9052_ALARM_Y_REG);
 127         if (ret < 0) {
 128                 rtc_err(rtc, "Failed to read ALM: %d\n", ret);
 129                 return ret;
 130         }
 131
 132         return !!(ret&DA9052_ALARM_Y_ALARM_ON);
 133 }
 134
 135 static int da9052_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm)
 136 {
 137         struct da9052_rtc *rtc = dev_get_drvdata(dev);
 138         uint8_t v[6];
 139         int ret;
 140
 141         ret = da9052_group_read(rtc->da9052, DA9052_COUNT_S_REG, 6, v);
 142         if (ret < 0) {
 143                 rtc_err(rtc, "Failed to read RTC time : %d\n", ret);
 144                 return ret;
 145         }
 146
 147         rtc_tm->tm_year = (v[5] & DA9052_RTC_YEAR) + 100;
 148         rtc_tm->tm_mon  = (v[4] & DA9052_RTC_MONTH) - 1;
 149         rtc_tm->tm_mday = v[3] & DA9052_RTC_DAY;
 150         rtc_tm->tm_hour = v[2] & DA9052_RTC_HOUR;
 151         rtc_tm->tm_min  = v[1] & DA9052_RTC_MIN;
 152         rtc_tm->tm_sec  = v[0] & DA9052_RTC_SEC;
 153
 154         ret = rtc_valid_tm(rtc_tm);
 155         return ret;
 156 }
 157
 158 static int da9052_rtc_set_time(struct device *dev, struct rtc_time *tm)
 159 {
 160         struct da9052_rtc *rtc;
 161         uint8_t v[6];
 162         int ret;
 163
 164         rtc = dev_get_drvdata(dev);
 165
 166         v[0] = tm->tm_sec;
 167         v[1] = tm->tm_min;
 168         v[2] = tm->tm_hour;
 169         v[3] = tm->tm_mday;
 170         v[4] = tm->tm_mon + 1;
 171         v[5] = tm->tm_year - 100;
 172
 173         ret = da9052_group_write(rtc->da9052, DA9052_COUNT_S_REG, 6, v);
 174         if (ret < 0)
 175                 rtc_err(rtc, "failed to set RTC time: %d\n", ret);
 176         return ret;
 177 }
 178
 179 static int da9052_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 180 {
 181         int ret;
 182         struct rtc_time *tm = &alrm->time;
 183         struct da9052_rtc *rtc = dev_get_drvdata(dev);
 184
 185         ret = da9052_read_alarm(rtc, tm);
 186         if (ret < 0) {
 187                 rtc_err(rtc, "failed to read RTC alarm: %d\n", ret);
 188                 return ret;
 189         }
 190
 191         alrm->enabled = da9052_rtc_get_alarm_status(rtc);
 192         return 0;
 193 }
 194
 195 static int da9052_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 196 {
 197         int ret;
 198         struct rtc_time *tm = &alrm->time;
 199         struct da9052_rtc *rtc = dev_get_drvdata(dev);
 200
 201         ret = da9052_rtc_enable_alarm(rtc, 0);
 202         if (ret < 0)
 203                 return ret;
 204
 205         ret = da9052_set_alarm(rtc, tm);
 206         if (ret < 0)
 207                 return ret;
 208
 209         ret = da9052_rtc_enable_alarm(rtc, 1);
 210         return ret;
 211 }
 212
 213 static int da9052_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
 214 {
 215         struct da9052_rtc *rtc = dev_get_drvdata(dev);
 216
 217         return da9052_rtc_enable_alarm(rtc, enabled);
 218 }
 219
 220 static const struct rtc_class_ops da9052_rtc_ops = {
 221         .read_time      = da9052_rtc_read_time,
 222         .set_time       = da9052_rtc_set_time,
 223         .read_alarm     = da9052_rtc_read_alarm,
 224         .set_alarm      = da9052_rtc_set_alarm,
 225         .alarm_irq_enable = da9052_rtc_alarm_irq_enable,
 226 };
 227
 228 static int da9052_rtc_probe(struct platform_device *pdev)
 229 {
 230         struct da9052_rtc *rtc;
 231         int ret;
 232
 233         rtc = devm_kzalloc(&pdev->dev, sizeof(struct da9052_rtc), GFP_KERNEL);
 234         if (!rtc)
 235                 return -ENOMEM;
 236
 237         rtc->da9052 = dev_get_drvdata(pdev->dev.parent);
 238         platform_set_drvdata(pdev, rtc);
 239
 240         ret = da9052_reg_write(rtc->da9052, DA9052_BBAT_CONT_REG, 0xFE);
 241         if (ret < 0) {
 242                 rtc_err(rtc,
 243                         "Failed to setup RTC battery charging: %d\n", ret);
 244                 return ret;
 245         }
 246
 247         ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,
 248                                 DA9052_ALARM_Y_TICK_ON, 0);
 249         if (ret != 0)
 250                 rtc_err(rtc, "Failed to disable TICKS: %d\n", ret);
 251
 252         ret = da9052_request_irq(rtc->da9052, DA9052_IRQ_ALARM, "ALM",
 253                                 da9052_rtc_irq, rtc);
 254         if (ret != 0) {
 255                 rtc_err(rtc, "irq registration failed: %d\n", ret);
 256                 return ret;
 257         }
 258
 259         rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
 260                                        &da9052_rtc_ops, THIS_MODULE);
 261         return PTR_ERR_OR_ZERO(rtc->rtc);
 262 }
 263
 264 static struct platform_driver da9052_rtc_driver = {
 265         .probe  = da9052_rtc_probe,
 266         .driver = {
 267                 .name   = "da9052-rtc",
 268                 .owner  = THIS_MODULE,
 269         },
 270 };
 271
 272 module_platform_driver(da9052_rtc_driver);
 273
 274 MODULE_AUTHOR("Anthony Olech <Anthony.Olech@diasemi.com>");
 275 MODULE_DESCRIPTION("RTC driver for Dialog DA9052 PMIC");
 276 MODULE_LICENSE("GPL");
 277 MODULE_ALIAS("platform:da9052-rtc");