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
  19 #include <linux/mfd/da9052/da9052.h>
  20 #include <linux/mfd/da9052/reg.h>
  21
  22 #define rtc_err(da9052, fmt, ...) \
  23                 dev_err(da9052->dev, "%s: " fmt, __func__, ##__VA_ARGS__)
  24
  25 struct da9052_rtc {
  26         struct rtc_device *rtc;
  27         struct da9052 *da9052;
  28         int irq;
  29 };
  30
  31 static int da9052_rtc_enable_alarm(struct da9052 *da9052, bool enable)
  32 {
  33         int ret;
  34         if (enable) {
  35                 ret = da9052_reg_update(da9052, DA9052_ALARM_Y_REG,
  36                                         DA9052_ALARM_Y_ALARM_ON,
  37                                         DA9052_ALARM_Y_ALARM_ON);
  38                 if (ret != 0)
  39                         rtc_err(da9052, "Failed to enable ALM: %d\n", ret);
  40         } else {
  41                 ret = da9052_reg_update(da9052, DA9052_ALARM_Y_REG,
  42                                         DA9052_ALARM_Y_ALARM_ON, 0);
  43                 if (ret != 0)
  44                         rtc_err(da9052, "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         int ret;
  53
  54         ret = da9052_reg_read(rtc->da9052, DA9052_ALARM_MI_REG);
  55         if (ret < 0) {
  56                 rtc_err(rtc->da9052, "Read error: %d\n", ret);
  57                 return IRQ_NONE;
  58         }
  59
  60         if (ret & DA9052_ALARMMI_ALARMTYPE) {
  61                 da9052_rtc_enable_alarm(rtc->da9052, 0);
  62                 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);
  63         } else
  64                 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_PF);
  65
  66         return IRQ_HANDLED;
  67 }
  68
  69 static int da9052_read_alarm(struct da9052 *da9052, struct rtc_time *rtc_tm)
  70 {
  71         int ret;
  72         uint8_t v[5];
  73
  74         ret = da9052_group_read(da9052, DA9052_ALARM_MI_REG, 5, v);
  75         if (ret != 0) {
  76                 rtc_err(da9052, "Failed to group read ALM: %d\n", ret);
  77                 return ret;
  78         }
  79
  80         rtc_tm->tm_year = (v[4] & DA9052_RTC_YEAR) + 100;
  81         rtc_tm->tm_mon  = (v[3] & DA9052_RTC_MONTH) - 1;
  82         rtc_tm->tm_mday = v[2] & DA9052_RTC_DAY;
  83         rtc_tm->tm_hour = v[1] & DA9052_RTC_HOUR;
  84         rtc_tm->tm_min  = v[0] & DA9052_RTC_MIN;
  85
  86         ret = rtc_valid_tm(rtc_tm);
  87         if (ret != 0)
  88                 return ret;
  89         return ret;
  90 }
  91
  92 static int da9052_set_alarm(struct da9052 *da9052, struct rtc_time *rtc_tm)
  93 {
  94         int ret;
  95         uint8_t v[3];
  96
  97         rtc_tm->tm_year -= 100;
  98         rtc_tm->tm_mon += 1;
  99
 100         ret = da9052_reg_update(da9052, DA9052_ALARM_MI_REG,
 101                                 DA9052_RTC_MIN, rtc_tm->tm_min);
 102         if (ret != 0) {
 103                 rtc_err(da9052, "Failed to write ALRM MIN: %d\n", ret);
 104                 return ret;
 105         }
 106
 107         v[0] = rtc_tm->tm_hour;
 108         v[1] = rtc_tm->tm_mday;
 109         v[2] = rtc_tm->tm_mon;
 110
 111         ret = da9052_group_write(da9052, DA9052_ALARM_H_REG, 3, v);
 112         if (ret < 0)
 113                 return ret;
 114
 115         ret = da9052_reg_update(da9052, DA9052_ALARM_Y_REG,
 116                                 DA9052_RTC_YEAR, rtc_tm->tm_year);
 117         if (ret != 0)
 118                 rtc_err(da9052, "Failed to write ALRM YEAR: %d\n", ret);
 119
 120         return ret;
 121 }
 122
 123 static int da9052_rtc_get_alarm_status(struct da9052 *da9052)
 124 {
 125         int ret;
 126
 127         ret = da9052_reg_read(da9052, DA9052_ALARM_Y_REG);
 128         if (ret < 0) {
 129                 rtc_err(da9052, "Failed to read ALM: %d\n", ret);
 130                 return ret;
 131         }
 132         ret &= DA9052_ALARM_Y_ALARM_ON;
 133         return (ret > 0) ? 1 : 0;
 134 }
 135
 136 static int da9052_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm)
 137 {
 138         struct da9052_rtc *rtc = dev_get_drvdata(dev);
 139         uint8_t v[6];
 140         int ret;
 141
 142         ret = da9052_group_read(rtc->da9052, DA9052_COUNT_S_REG, 6, v);
 143         if (ret < 0) {
 144                 rtc_err(rtc->da9052, "Failed to read RTC time : %d\n", ret);
 145                 return ret;
 146         }
 147
 148         rtc_tm->tm_year = (v[5] & DA9052_RTC_YEAR) + 100;
 149         rtc_tm->tm_mon  = (v[4] & DA9052_RTC_MONTH) - 1;
 150         rtc_tm->tm_mday = v[3] & DA9052_RTC_DAY;
 151         rtc_tm->tm_hour = v[2] & DA9052_RTC_HOUR;
 152         rtc_tm->tm_min  = v[1] & DA9052_RTC_MIN;
 153         rtc_tm->tm_sec  = v[0] & DA9052_RTC_SEC;
 154
 155         ret = rtc_valid_tm(rtc_tm);
 156         if (ret != 0) {
 157                 rtc_err(rtc->da9052, "rtc_valid_tm failed: %d\n", ret);
 158                 return ret;
 159         }
 160
 161         return 0;
 162 }
 163
 164 static int da9052_rtc_set_time(struct device *dev, struct rtc_time *tm)
 165 {
 166         struct da9052_rtc *rtc;
 167         uint8_t v[6];
 168
 169         rtc = dev_get_drvdata(dev);
 170
 171         v[0] = tm->tm_sec;
 172         v[1] = tm->tm_min;
 173         v[2] = tm->tm_hour;
 174         v[3] = tm->tm_mday;
 175         v[4] = tm->tm_mon + 1;
 176         v[5] = tm->tm_year - 100;
 177
 178         return da9052_group_write(rtc->da9052, DA9052_COUNT_S_REG, 6, v);
 179 }
 180
 181 static int da9052_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 182 {
 183         int ret;
 184         struct rtc_time *tm = &alrm->time;
 185         struct da9052_rtc *rtc = dev_get_drvdata(dev);
 186
 187         ret = da9052_read_alarm(rtc->da9052, tm);
 188
 189         if (ret)
 190                 return ret;
 191
 192         alrm->enabled = da9052_rtc_get_alarm_status(rtc->da9052);
 193
 194         return 0;
 195 }
 196
 197 static int da9052_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 198 {
 199         int ret;
 200         struct rtc_time *tm = &alrm->time;
 201         struct da9052_rtc *rtc = dev_get_drvdata(dev);
 202
 203         ret = da9052_rtc_enable_alarm(rtc->da9052, 0);
 204         if (ret < 0)
 205                 return ret;
 206
 207         ret = da9052_set_alarm(rtc->da9052, tm);
 208         if (ret)
 209                 return ret;
 210
 211         ret = da9052_rtc_enable_alarm(rtc->da9052, 1);
 212
 213         return ret;
 214 }
 215
 216 static int da9052_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
 217 {
 218         struct da9052_rtc *rtc = dev_get_drvdata(dev);
 219
 220         return da9052_rtc_enable_alarm(rtc->da9052, enabled);
 221 }
 222
 223 static const struct rtc_class_ops da9052_rtc_ops = {
 224         .read_time      = da9052_rtc_read_time,
 225         .set_time       = da9052_rtc_set_time,
 226         .read_alarm     = da9052_rtc_read_alarm,
 227         .set_alarm      = da9052_rtc_set_alarm,
 228         .alarm_irq_enable = da9052_rtc_alarm_irq_enable,
 229 };
 230
 231 static int da9052_rtc_probe(struct platform_device *pdev)
 232 {
 233         struct da9052_rtc *rtc;
 234         int ret;
 235
 236         rtc = devm_kzalloc(&pdev->dev, sizeof(struct da9052_rtc), GFP_KERNEL);
 237         if (!rtc)
 238                 return -ENOMEM;
 239
 240         rtc->da9052 = dev_get_drvdata(pdev->dev.parent);
 241         platform_set_drvdata(pdev, rtc);
 242         rtc->irq = platform_get_irq_byname(pdev, "ALM");
 243         ret = request_threaded_irq(rtc->irq, NULL, da9052_rtc_irq,
 244                                    IRQF_TRIGGER_LOW | IRQF_ONESHOT,
 245                                    "ALM", rtc);
 246         if (ret != 0) {
 247                 rtc_err(rtc->da9052, "irq registration failed: %d\n", ret);
 248                 return ret;
 249         }
 250
 251         rtc->rtc = rtc_device_register(pdev->name, &pdev->dev,
 252                                        &da9052_rtc_ops, THIS_MODULE);
 253         if (IS_ERR(rtc->rtc)) {
 254                 ret = PTR_ERR(rtc->rtc);
 255                 goto err_free_irq;
 256         }
 257
 258         return 0;
 259
 260 err_free_irq:
 261         free_irq(rtc->irq, rtc);
 262         return ret;
 263 }
 264
 265 static int da9052_rtc_remove(struct platform_device *pdev)
 266 {
 267         struct da9052_rtc *rtc = pdev->dev.platform_data;
 268
 269         rtc_device_unregister(rtc->rtc);
 270         free_irq(rtc->irq, rtc);
 271         platform_set_drvdata(pdev, NULL);
 272
 273         return 0;
 274 }
 275
 276 static struct platform_driver da9052_rtc_driver = {
 277         .probe  = da9052_rtc_probe,
 278         .remove = da9052_rtc_remove,
 279         .driver = {
 280                 .name   = "da9052-rtc",
 281                 .owner  = THIS_MODULE,
 282         },
 283 };
 284
 285 module_platform_driver(da9052_rtc_driver);
 286
 287 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
 288 MODULE_DESCRIPTION("RTC driver for Dialog DA9052 PMIC");
 289 MODULE_LICENSE("GPL");
 290 MODULE_ALIAS("platform:da9052-rtc");