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(da9052, fmt, ...) \
  24                 dev_err(da9052->dev, "%s: " fmt, __func__, ##__VA_ARGS__)
  25
  26 struct da9052_rtc {
  27         struct rtc_device *rtc;
  28         struct da9052 *da9052;
  29         int irq;
  30 };
  31
  32 static int da9052_rtc_enable_alarm(struct da9052 *da9052, bool enable)
  33 {
  34         int ret;
  35         if (enable) {
  36                 ret = da9052_reg_update(da9052, DA9052_ALARM_Y_REG,
  37                                         DA9052_ALARM_Y_ALARM_ON,
  38                                         DA9052_ALARM_Y_ALARM_ON);
  39                 if (ret != 0)
  40                         rtc_err(da9052, "Failed to enable ALM: %d\n", ret);
  41         } else {
  42                 ret = da9052_reg_update(da9052, DA9052_ALARM_Y_REG,
  43                                         DA9052_ALARM_Y_ALARM_ON, 0);
  44                 if (ret != 0)
  45                         rtc_err(da9052, "Write error: %d\n", ret);
  46         }
  47         return ret;
  48 }
  49
  50 static irqreturn_t da9052_rtc_irq(int irq, void *data)
  51 {
  52         struct da9052_rtc *rtc = data;
  53         int ret;
  54
  55         ret = da9052_reg_read(rtc->da9052, DA9052_ALARM_MI_REG);
  56         if (ret < 0) {
  57                 rtc_err(rtc->da9052, "Read error: %d\n", ret);
  58                 return IRQ_NONE;
  59         }
  60
  61         if (ret & DA9052_ALARMMI_ALARMTYPE) {
  62                 da9052_rtc_enable_alarm(rtc->da9052, 0);
  63                 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);
  64         } else
  65                 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_PF);
  66
  67         return IRQ_HANDLED;
  68 }
  69
  70 static int da9052_read_alarm(struct da9052 *da9052, struct rtc_time *rtc_tm)
  71 {
  72         int ret;
  73         uint8_t v[5];
  74
  75         ret = da9052_group_read(da9052, DA9052_ALARM_MI_REG, 5, v);
  76         if (ret != 0) {
  77                 rtc_err(da9052, "Failed to group read ALM: %d\n", ret);
  78                 return ret;
  79         }
  80
  81         rtc_tm->tm_year = (v[4] & DA9052_RTC_YEAR) + 100;
  82         rtc_tm->tm_mon  = (v[3] & DA9052_RTC_MONTH) - 1;
  83         rtc_tm->tm_mday = v[2] & DA9052_RTC_DAY;
  84         rtc_tm->tm_hour = v[1] & DA9052_RTC_HOUR;
  85         rtc_tm->tm_min  = v[0] & DA9052_RTC_MIN;
  86
  87         ret = rtc_valid_tm(rtc_tm);
  88         if (ret != 0)
  89                 return ret;
  90         return ret;
  91 }
  92
  93 static int da9052_set_alarm(struct da9052 *da9052, struct rtc_time *rtc_tm)
  94 {
  95         int ret;
  96         uint8_t v[3];
  97
  98         rtc_tm->tm_year -= 100;
  99         rtc_tm->tm_mon += 1;
 100
 101         ret = da9052_reg_update(da9052, DA9052_ALARM_MI_REG,
 102                                 DA9052_RTC_MIN, rtc_tm->tm_min);
 103         if (ret != 0) {
 104                 rtc_err(da9052, "Failed to write ALRM MIN: %d\n", ret);
 105                 return ret;
 106         }
 107
 108         v[0] = rtc_tm->tm_hour;
 109         v[1] = rtc_tm->tm_mday;
 110         v[2] = rtc_tm->tm_mon;
 111
 112         ret = da9052_group_write(da9052, DA9052_ALARM_H_REG, 3, v);
 113         if (ret < 0)
 114                 return ret;
 115
 116         ret = da9052_reg_update(da9052, DA9052_ALARM_Y_REG,
 117                                 DA9052_RTC_YEAR, rtc_tm->tm_year);
 118         if (ret != 0)
 119                 rtc_err(da9052, "Failed to write ALRM YEAR: %d\n", ret);
 120
 121         return ret;
 122 }
 123
 124 static int da9052_rtc_get_alarm_status(struct da9052 *da9052)
 125 {
 126         int ret;
 127
 128         ret = da9052_reg_read(da9052, DA9052_ALARM_Y_REG);
 129         if (ret < 0) {
 130                 rtc_err(da9052, "Failed to read ALM: %d\n", ret);
 131                 return ret;
 132         }
 133         ret &= DA9052_ALARM_Y_ALARM_ON;
 134         return (ret > 0) ? 1 : 0;
 135 }
 136
 137 static int da9052_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm)
 138 {
 139         struct da9052_rtc *rtc = dev_get_drvdata(dev);
 140         uint8_t v[6];
 141         int ret;
 142
 143         ret = da9052_group_read(rtc->da9052, DA9052_COUNT_S_REG, 6, v);
 144         if (ret < 0) {
 145                 rtc_err(rtc->da9052, "Failed to read RTC time : %d\n", ret);
 146                 return ret;
 147         }
 148
 149         rtc_tm->tm_year = (v[5] & DA9052_RTC_YEAR) + 100;
 150         rtc_tm->tm_mon  = (v[4] & DA9052_RTC_MONTH) - 1;
 151         rtc_tm->tm_mday = v[3] & DA9052_RTC_DAY;
 152         rtc_tm->tm_hour = v[2] & DA9052_RTC_HOUR;
 153         rtc_tm->tm_min  = v[1] & DA9052_RTC_MIN;
 154         rtc_tm->tm_sec  = v[0] & DA9052_RTC_SEC;
 155
 156         ret = rtc_valid_tm(rtc_tm);
 157         if (ret != 0) {
 158                 rtc_err(rtc->da9052, "rtc_valid_tm failed: %d\n", ret);
 159                 return ret;
 160         }
 161
 162         return 0;
 163 }
 164
 165 static int da9052_rtc_set_time(struct device *dev, struct rtc_time *tm)
 166 {
 167         struct da9052_rtc *rtc;
 168         uint8_t v[6];
 169
 170         rtc = dev_get_drvdata(dev);
 171
 172         v[0] = tm->tm_sec;
 173         v[1] = tm->tm_min;
 174         v[2] = tm->tm_hour;
 175         v[3] = tm->tm_mday;
 176         v[4] = tm->tm_mon + 1;
 177         v[5] = tm->tm_year - 100;
 178
 179         return da9052_group_write(rtc->da9052, DA9052_COUNT_S_REG, 6, v);
 180 }
 181
 182 static int da9052_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 183 {
 184         int ret;
 185         struct rtc_time *tm = &alrm->time;
 186         struct da9052_rtc *rtc = dev_get_drvdata(dev);
 187
 188         ret = da9052_read_alarm(rtc->da9052, tm);
 189
 190         if (ret)
 191                 return ret;
 192
 193         alrm->enabled = da9052_rtc_get_alarm_status(rtc->da9052);
 194
 195         return 0;
 196 }
 197
 198 static int da9052_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 199 {
 200         int ret;
 201         struct rtc_time *tm = &alrm->time;
 202         struct da9052_rtc *rtc = dev_get_drvdata(dev);
 203
 204         ret = da9052_rtc_enable_alarm(rtc->da9052, 0);
 205         if (ret < 0)
 206                 return ret;
 207
 208         ret = da9052_set_alarm(rtc->da9052, tm);
 209         if (ret)
 210                 return ret;
 211
 212         ret = da9052_rtc_enable_alarm(rtc->da9052, 1);
 213
 214         return ret;
 215 }
 216
 217 static int da9052_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
 218 {
 219         struct da9052_rtc *rtc = dev_get_drvdata(dev);
 220
 221         return da9052_rtc_enable_alarm(rtc->da9052, enabled);
 222 }
 223
 224 static const struct rtc_class_ops da9052_rtc_ops = {
 225         .read_time      = da9052_rtc_read_time,
 226         .set_time       = da9052_rtc_set_time,
 227         .read_alarm     = da9052_rtc_read_alarm,
 228         .set_alarm      = da9052_rtc_set_alarm,
 229         .alarm_irq_enable = da9052_rtc_alarm_irq_enable,
 230 };
 231
 232 static int da9052_rtc_probe(struct platform_device *pdev)
 233 {
 234         struct da9052_rtc *rtc;
 235         int ret;
 236
 237         rtc = devm_kzalloc(&pdev->dev, sizeof(struct da9052_rtc), GFP_KERNEL);
 238         if (!rtc)
 239                 return -ENOMEM;
 240
 241         rtc->da9052 = dev_get_drvdata(pdev->dev.parent);
 242         platform_set_drvdata(pdev, rtc);
 243         rtc->irq =  DA9052_IRQ_ALARM;
 244         ret = da9052_request_irq(rtc->da9052, rtc->irq, "ALM",
 245                                 da9052_rtc_irq, rtc);
 246         if (ret != 0) {
 247                 rtc_err(rtc->da9052, "irq registration failed: %d\n", ret);
 248                 return ret;
 249         }
 250
 251         rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
 252                                        &da9052_rtc_ops, THIS_MODULE);
 253         return PTR_ERR_OR_ZERO(rtc->rtc);
 254 }
 255
 256 static struct platform_driver da9052_rtc_driver = {
 257         .probe  = da9052_rtc_probe,
 258         .driver = {
 259                 .name   = "da9052-rtc",
 260                 .owner  = THIS_MODULE,
 261         },
 262 };
 263
 264 module_platform_driver(da9052_rtc_driver);
 265
 266 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
 267 MODULE_DESCRIPTION("RTC driver for Dialog DA9052 PMIC");
 268 MODULE_LICENSE("GPL");
 269 MODULE_ALIAS("platform:da9052-rtc");