Quelle  rtc-da9063.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0+
/*
 * Real time clock device driver for DA9063
 * Copyright (C) 2013-2015  Dialog Semiconductor Ltd.
 */

#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_wakeirq.h>
#include <linux/regmap.h>
#include <linux/rtc.h>
#include <linux/slab.h>

#include <linux/mfd/da9062/registers.h>
#include <linux/mfd/da9063/registers.h>
#include <linux/mfd/da9063/core.h>

#define YEARS_TO_DA9063(year)  ((year) - 100)
#define MONTHS_TO_DA9063(month)  ((month) + 1)
#define YEARS_FROM_DA9063(year)  ((year) + 100)
#define MONTHS_FROM_DA9063(month) ((month) - 1)

enum {
 RTC_SEC = 0,
 RTC_MIN = 1,
 RTC_HOUR = 2,
 RTC_DAY = 3,
 RTC_MONTH = 4,
 RTC_YEAR = 5,
 RTC_DATA_LEN
};

struct da9063_compatible_rtc_regmap {
 /* REGS */
 int rtc_enable_reg;
 int rtc_enable_32k_crystal_reg;
 int rtc_alarm_secs_reg;
 int rtc_alarm_year_reg;
 int rtc_count_secs_reg;
 int rtc_count_year_reg;
 int rtc_event_reg;
 /* MASKS */
 int rtc_enable_mask;
 int rtc_crystal_mask;
 int rtc_event_alarm_mask;
 int rtc_alarm_on_mask;
 int rtc_alarm_status_mask;
 int rtc_tick_on_mask;
 int rtc_ready_to_read_mask;
 int rtc_count_sec_mask;
 int rtc_count_min_mask;
 int rtc_count_hour_mask;
 int rtc_count_day_mask;
 int rtc_count_month_mask;
 int rtc_count_year_mask;
 /* ALARM CONFIG */
 int rtc_data_start;
 int rtc_alarm_len;
};

struct da9063_compatible_rtc {
 struct rtc_device *rtc_dev;
 struct rtc_time alarm_time;
 struct regmap *regmap;
 const struct da9063_compatible_rtc_regmap *config;
 bool rtc_sync;
};

static const struct da9063_compatible_rtc_regmap da9063_ad_regs = {
 /* REGS */
 .rtc_enable_reg             = DA9063_REG_CONTROL_E,
 .rtc_alarm_secs_reg         = DA9063_AD_REG_ALARM_MI,
 .rtc_alarm_year_reg         = DA9063_AD_REG_ALARM_Y,
 .rtc_count_secs_reg         = DA9063_REG_COUNT_S,
 .rtc_count_year_reg         = DA9063_REG_COUNT_Y,
 .rtc_event_reg              = DA9063_REG_EVENT_A,
 /* MASKS */
 .rtc_enable_mask            = DA9063_RTC_EN,
 .rtc_crystal_mask           = DA9063_CRYSTAL,
 .rtc_enable_32k_crystal_reg = DA9063_REG_EN_32K,
 .rtc_event_alarm_mask       = DA9063_E_ALARM,
 .rtc_alarm_on_mask          = DA9063_ALARM_ON,
 .rtc_alarm_status_mask      = DA9063_ALARM_STATUS_ALARM |
          DA9063_ALARM_STATUS_TICK,
 .rtc_tick_on_mask           = DA9063_TICK_ON,
 .rtc_ready_to_read_mask     = DA9063_RTC_READ,
 .rtc_count_sec_mask         = DA9063_COUNT_SEC_MASK,
 .rtc_count_min_mask         = DA9063_COUNT_MIN_MASK,
 .rtc_count_hour_mask        = DA9063_COUNT_HOUR_MASK,
 .rtc_count_day_mask         = DA9063_COUNT_DAY_MASK,
 .rtc_count_month_mask       = DA9063_COUNT_MONTH_MASK,
 .rtc_count_year_mask        = DA9063_COUNT_YEAR_MASK,
 /* ALARM CONFIG */
 .rtc_data_start             = RTC_MIN,
 .rtc_alarm_len              = RTC_DATA_LEN - 1,
};

static const struct da9063_compatible_rtc_regmap da9063_bb_regs = {
 /* REGS */
 .rtc_enable_reg             = DA9063_REG_CONTROL_E,
 .rtc_alarm_secs_reg         = DA9063_BB_REG_ALARM_S,
 .rtc_alarm_year_reg         = DA9063_BB_REG_ALARM_Y,
 .rtc_count_secs_reg         = DA9063_REG_COUNT_S,
 .rtc_count_year_reg         = DA9063_REG_COUNT_Y,
 .rtc_event_reg              = DA9063_REG_EVENT_A,
 /* MASKS */
 .rtc_enable_mask            = DA9063_RTC_EN,
 .rtc_crystal_mask           = DA9063_CRYSTAL,
 .rtc_enable_32k_crystal_reg = DA9063_REG_EN_32K,
 .rtc_event_alarm_mask       = DA9063_E_ALARM,
 .rtc_alarm_on_mask          = DA9063_ALARM_ON,
 .rtc_alarm_status_mask      = DA9063_ALARM_STATUS_ALARM |
          DA9063_ALARM_STATUS_TICK,
 .rtc_tick_on_mask           = DA9063_TICK_ON,
 .rtc_ready_to_read_mask     = DA9063_RTC_READ,
 .rtc_count_sec_mask         = DA9063_COUNT_SEC_MASK,
 .rtc_count_min_mask         = DA9063_COUNT_MIN_MASK,
 .rtc_count_hour_mask        = DA9063_COUNT_HOUR_MASK,
 .rtc_count_day_mask         = DA9063_COUNT_DAY_MASK,
 .rtc_count_month_mask       = DA9063_COUNT_MONTH_MASK,
 .rtc_count_year_mask        = DA9063_COUNT_YEAR_MASK,
 /* ALARM CONFIG */
 .rtc_data_start             = RTC_SEC,
 .rtc_alarm_len              = RTC_DATA_LEN,
};

static const struct da9063_compatible_rtc_regmap da9062_aa_regs = {
 /* REGS */
 .rtc_enable_reg             = DA9062AA_CONTROL_E,
 .rtc_alarm_secs_reg         = DA9062AA_ALARM_S,
 .rtc_alarm_year_reg         = DA9062AA_ALARM_Y,
 .rtc_count_secs_reg         = DA9062AA_COUNT_S,
 .rtc_count_year_reg         = DA9062AA_COUNT_Y,
 .rtc_event_reg              = DA9062AA_EVENT_A,
 /* MASKS */
 .rtc_enable_mask            = DA9062AA_RTC_EN_MASK,
 .rtc_crystal_mask           = DA9062AA_CRYSTAL_MASK,
 .rtc_enable_32k_crystal_reg = DA9062AA_EN_32K,
 .rtc_event_alarm_mask       = DA9062AA_M_ALARM_MASK,
 .rtc_alarm_on_mask          = DA9062AA_ALARM_ON_MASK,
 .rtc_alarm_status_mask      = (0x02 << 6),
 .rtc_tick_on_mask           = DA9062AA_TICK_ON_MASK,
 .rtc_ready_to_read_mask     = DA9062AA_RTC_READ_MASK,
 .rtc_count_sec_mask         = DA9062AA_COUNT_SEC_MASK,
 .rtc_count_min_mask         = DA9062AA_COUNT_MIN_MASK,
 .rtc_count_hour_mask        = DA9062AA_COUNT_HOUR_MASK,
 .rtc_count_day_mask         = DA9062AA_COUNT_DAY_MASK,
 .rtc_count_month_mask       = DA9062AA_COUNT_MONTH_MASK,
 .rtc_count_year_mask        = DA9062AA_COUNT_YEAR_MASK,
 /* ALARM CONFIG */
 .rtc_data_start             = RTC_SEC,
 .rtc_alarm_len              = RTC_DATA_LEN,
};

static const struct of_device_id da9063_compatible_reg_id_table[] = {
 { .compatible = "dlg,da9063-rtc", .data = &da9063_bb_regs },
 { .compatible = "dlg,da9062-rtc", .data = &da9062_aa_regs },
 { },
};
MODULE_DEVICE_TABLE(of, da9063_compatible_reg_id_table);

static void da9063_data_to_tm(u8 *data, struct rtc_time *tm,
         struct da9063_compatible_rtc *rtc)
{
 const struct da9063_compatible_rtc_regmap *config = rtc->config;

 tm->tm_sec  = data[RTC_SEC]  & config->rtc_count_sec_mask;
 tm->tm_min  = data[RTC_MIN]  & config->rtc_count_min_mask;
 tm->tm_hour = data[RTC_HOUR] & config->rtc_count_hour_mask;
 tm->tm_mday = data[RTC_DAY]  & config->rtc_count_day_mask;
 tm->tm_mon  = MONTHS_FROM_DA9063(data[RTC_MONTH] &
      config->rtc_count_month_mask);
 tm->tm_year = YEARS_FROM_DA9063(data[RTC_YEAR] &
     config->rtc_count_year_mask);
}

static void da9063_tm_to_data(struct rtc_time *tm, u8 *data,
         struct da9063_compatible_rtc *rtc)
{
 const struct da9063_compatible_rtc_regmap *config = rtc->config;

 data[RTC_SEC]   = tm->tm_sec & config->rtc_count_sec_mask;
 data[RTC_MIN]   = tm->tm_min & config->rtc_count_min_mask;
 data[RTC_HOUR]  = tm->tm_hour & config->rtc_count_hour_mask;
 data[RTC_DAY]   = tm->tm_mday & config->rtc_count_day_mask;
 data[RTC_MONTH] = MONTHS_TO_DA9063(tm->tm_mon) &
    config->rtc_count_month_mask;
 data[RTC_YEAR]  = YEARS_TO_DA9063(tm->tm_year) &
    config->rtc_count_year_mask;
}

static int da9063_rtc_alarm_irq_enable(struct device *dev,
           unsigned int enabled)
{
 struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
 const struct da9063_compatible_rtc_regmap *config = rtc->config;
 u8 set_bit = enabled ? config->rtc_alarm_on_mask : 0;

 return regmap_update_bits(rtc->regmap,
      config->rtc_alarm_year_reg,
      config->rtc_alarm_on_mask,
      set_bit);
}

static int da9063_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
 struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
 const struct da9063_compatible_rtc_regmap *config = rtc->config;
 unsigned long tm_secs;
 unsigned long al_secs;
 u8 data[RTC_DATA_LEN];
 int ret;

 ret = regmap_bulk_read(rtc->regmap,
          config->rtc_count_secs_reg,
          data, RTC_DATA_LEN);
 if (ret < 0) {
  dev_err(dev, "Failed to read RTC time data: %d\n", ret);
  return ret;
 }

 if (!(data[RTC_SEC] & config->rtc_ready_to_read_mask)) {
  dev_dbg(dev, "RTC not yet ready to be read by the host\n");
  return -EINVAL;
 }

 da9063_data_to_tm(data, tm, rtc);

 tm_secs = rtc_tm_to_time64(tm);
 al_secs = rtc_tm_to_time64(&rtc->alarm_time);

 /* handle the rtc synchronisation delay */
 if (rtc->rtc_sync && al_secs - tm_secs == 1)
  memcpy(tm, &rtc->alarm_time, sizeof(struct rtc_time));
 else
  rtc->rtc_sync = false;

 return 0;
}

static int da9063_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
 struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
 const struct da9063_compatible_rtc_regmap *config = rtc->config;
 u8 data[RTC_DATA_LEN];
 int ret;

 da9063_tm_to_data(tm, data, rtc);
 ret = regmap_bulk_write(rtc->regmap,
    config->rtc_count_secs_reg,
    data, RTC_DATA_LEN);
 if (ret < 0)
  dev_err(dev, "Failed to set RTC time data: %d\n", ret);

 return ret;
}

static int da9063_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
 struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
 const struct da9063_compatible_rtc_regmap *config = rtc->config;
 u8 data[RTC_DATA_LEN];
 int ret;
 unsigned int val;

 data[RTC_SEC] = 0;
 ret = regmap_bulk_read(rtc->regmap,
          config->rtc_alarm_secs_reg,
          &data[config->rtc_data_start],
          config->rtc_alarm_len);
 if (ret < 0)
  return ret;

 da9063_data_to_tm(data, &alrm->time, rtc);

 alrm->enabled = !!(data[RTC_YEAR] & config->rtc_alarm_on_mask);

 ret = regmap_read(rtc->regmap,
     config->rtc_event_reg,
     &val);
 if (ret < 0)
  return ret;

 if (val & config->rtc_event_alarm_mask)
  alrm->pending = 1;
 else
  alrm->pending = 0;

 return 0;
}

static int da9063_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
 struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
 const struct da9063_compatible_rtc_regmap *config = rtc->config;
 u8 data[RTC_DATA_LEN];
 int ret;

 da9063_tm_to_data(&alrm->time, data, rtc);

 ret = da9063_rtc_alarm_irq_enable(dev, 0);
 if (ret < 0) {
  dev_err(dev, "Failed to stop alarm: %d\n", ret);
  return ret;
 }

 ret = regmap_bulk_write(rtc->regmap,
    config->rtc_alarm_secs_reg,
    &data[config->rtc_data_start],
    config->rtc_alarm_len);
 if (ret < 0) {
  dev_err(dev, "Failed to write alarm: %d\n", ret);
  return ret;
 }

 da9063_data_to_tm(data, &rtc->alarm_time, rtc);

 if (alrm->enabled) {
  ret = da9063_rtc_alarm_irq_enable(dev, 1);
  if (ret < 0) {
   dev_err(dev, "Failed to start alarm: %d\n", ret);
   return ret;
  }
 }

 return ret;
}

static irqreturn_t da9063_alarm_event(int irq, void *data)
{
 struct da9063_compatible_rtc *rtc = data;
 const struct da9063_compatible_rtc_regmap *config = rtc->config;

 regmap_update_bits(rtc->regmap,
      config->rtc_alarm_year_reg,
      config->rtc_alarm_on_mask,
      0);

 rtc->rtc_sync = true;
 rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF);

 return IRQ_HANDLED;
}

static const struct rtc_class_ops da9063_rtc_ops = {
 .read_time = da9063_rtc_read_time,
 .set_time = da9063_rtc_set_time,
 .read_alarm = da9063_rtc_read_alarm,
 .set_alarm = da9063_rtc_set_alarm,
 .alarm_irq_enable = da9063_rtc_alarm_irq_enable,
};

static int da9063_rtc_probe(struct platform_device *pdev)
{
 struct da9063_compatible_rtc *rtc;
 const struct da9063_compatible_rtc_regmap *config;
 int irq_alarm;
 u8 data[RTC_DATA_LEN];
 int ret;

 if (!pdev->dev.of_node)
  return -ENXIO;

 rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
 if (!rtc)
  return -ENOMEM;

 rtc->config = device_get_match_data(&pdev->dev);
 if (of_device_is_compatible(pdev->dev.of_node, "dlg,da9063-rtc")) {
  struct da9063 *chip = dev_get_drvdata(pdev->dev.parent);

  if (chip->variant_code == PMIC_DA9063_AD)
   rtc->config = &da9063_ad_regs;
 }

 rtc->regmap = dev_get_regmap(pdev->dev.parent, NULL);
 if (!rtc->regmap) {
  dev_warn(&pdev->dev, "Parent regmap unavailable.\n");
  return -ENXIO;
 }

 config = rtc->config;
 ret = regmap_update_bits(rtc->regmap,
     config->rtc_enable_reg,
     config->rtc_enable_mask,
     config->rtc_enable_mask);
 if (ret < 0)
  return dev_err_probe(&pdev->dev, ret, "Failed to enable RTC\n");

 ret = regmap_update_bits(rtc->regmap,
     config->rtc_enable_32k_crystal_reg,
     config->rtc_crystal_mask,
     config->rtc_crystal_mask);
 if (ret < 0)
  return dev_err_probe(&pdev->dev, ret,
         "Failed to run 32kHz oscillator\n");

 ret = regmap_update_bits(rtc->regmap,
     config->rtc_alarm_secs_reg,
     config->rtc_alarm_status_mask,
     0);
 if (ret < 0)
  return dev_err_probe(&pdev->dev, ret,
         "Failed to access RTC alarm register\n");

 ret = regmap_update_bits(rtc->regmap,
     config->rtc_alarm_secs_reg,
     DA9063_ALARM_STATUS_ALARM,
     DA9063_ALARM_STATUS_ALARM);
 if (ret < 0)
  return dev_err_probe(&pdev->dev, ret,
         "Failed to access RTC alarm register\n");

 ret = regmap_update_bits(rtc->regmap,
     config->rtc_alarm_year_reg,
     config->rtc_tick_on_mask,
     0);
 if (ret < 0)
  return dev_err_probe(&pdev->dev, ret,
         "Failed to disable TICKs\n");

 data[RTC_SEC] = 0;
 ret = regmap_bulk_read(rtc->regmap,
          config->rtc_alarm_secs_reg,
          &data[config->rtc_data_start],
          config->rtc_alarm_len);
 if (ret < 0)
  return dev_err_probe(&pdev->dev, ret,
         "Failed to read initial alarm data\n");

 platform_set_drvdata(pdev, rtc);

 rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
 if (IS_ERR(rtc->rtc_dev))
  return PTR_ERR(rtc->rtc_dev);

 rtc->rtc_dev->ops = &da9063_rtc_ops;
 rtc->rtc_dev->range_min = RTC_TIMESTAMP_BEGIN_2000;
 rtc->rtc_dev->range_max = RTC_TIMESTAMP_END_2063;

 da9063_data_to_tm(data, &rtc->alarm_time, rtc);
 rtc->rtc_sync = false;

 if (config->rtc_data_start != RTC_SEC) {
  set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->rtc_dev->features);
  /*
 * TODO: some models have alarms on a minute boundary but still
 * support real hardware interrupts.
 */
  clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->rtc_dev->features);
 }

 irq_alarm = platform_get_irq_byname_optional(pdev, "ALARM");
 if (irq_alarm >= 0) {
  ret = devm_request_threaded_irq(&pdev->dev, irq_alarm, NULL,
      da9063_alarm_event,
      IRQF_TRIGGER_LOW | IRQF_ONESHOT,
      "ALARM", rtc);
  if (ret)
   dev_err(&pdev->dev,
    "Failed to request ALARM IRQ %d: %d\n",
    irq_alarm, ret);

  ret = dev_pm_set_wake_irq(&pdev->dev, irq_alarm);
  if (ret)
   dev_warn(&pdev->dev,
     "Failed to set IRQ %d as a wake IRQ: %d\n",
     irq_alarm, ret);

  device_init_wakeup(&pdev->dev, true);
 }  else if (irq_alarm != -ENXIO) {
  return irq_alarm;
 } else {
  clear_bit(RTC_FEATURE_ALARM, rtc->rtc_dev->features);
 }

 return devm_rtc_register_device(rtc->rtc_dev);
}

static struct platform_driver da9063_rtc_driver = {
 .probe  = da9063_rtc_probe,
 .driver  = {
  .name = DA9063_DRVNAME_RTC,
  .of_match_table = da9063_compatible_reg_id_table,
 },
};

module_platform_driver(da9063_rtc_driver);

MODULE_AUTHOR("S Twiss ");
MODULE_DESCRIPTION("Real time clock device driver for Dialog DA9063");
MODULE_LICENSE("GPL");