rtc: da9063: RTC driver
authorOpensource [Steve Twiss] <stwiss.opensource@diasemi.com>
Fri, 6 Jun 2014 21:36:03 +0000 (14:36 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 6 Jun 2014 23:08:08 +0000 (16:08 -0700)
Add the RTC driver for DA9063.

[akpm@linux-foundation.org: coding-style tweaks]
Signed-off-by: Opensource [Steve Twiss] <stwiss.opensource@diasemi.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Mark Brown <broonie@linaro.org>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: David Dajun Chen <david.chen@diasemi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/rtc/Kconfig
drivers/rtc/Makefile
drivers/rtc/rtc-da9063.c [new file with mode: 0644]

index 486d34b..71988b6 100644 (file)
@@ -777,6 +777,16 @@ config RTC_DRV_DA9055
          This driver can also be built as a module. If so, the module
          will be called rtc-da9055
 
+config RTC_DRV_DA9063
+       tristate "Dialog Semiconductor DA9063 RTC"
+       depends on MFD_DA9063
+       help
+         If you say yes here you will get support for the RTC subsystem
+         of the Dialog Semiconductor DA9063.
+
+         This driver can also be built as a module. If so, the module
+         will be called "rtc-da9063".
+
 config RTC_DRV_EFI
        tristate "EFI RTC"
        depends on IA64
index 9d77755..70347d0 100644 (file)
@@ -32,6 +32,7 @@ obj-$(CONFIG_RTC_DRV_CMOS)    += rtc-cmos.o
 obj-$(CONFIG_RTC_DRV_COH901331)        += rtc-coh901331.o
 obj-$(CONFIG_RTC_DRV_DA9052)   += rtc-da9052.o
 obj-$(CONFIG_RTC_DRV_DA9055)   += rtc-da9055.o
+obj-$(CONFIG_RTC_DRV_DA9063)   += rtc-da9063.o
 obj-$(CONFIG_RTC_DRV_DAVINCI)  += rtc-davinci.o
 obj-$(CONFIG_RTC_DRV_DM355EVM) += rtc-dm355evm.o
 obj-$(CONFIG_RTC_DRV_VRTC)     += rtc-mrst.o
diff --git a/drivers/rtc/rtc-da9063.c b/drivers/rtc/rtc-da9063.c
new file mode 100644 (file)
index 0000000..5953930
--- /dev/null
@@ -0,0 +1,333 @@
+/* rtc-da9063.c - Real time clock device driver for DA9063
+ * Copyright (C) 2013-14  Dialog Semiconductor Ltd.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/rtc.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/regmap.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)
+
+#define RTC_DATA_LEN   (DA9063_REG_COUNT_Y - DA9063_REG_COUNT_S + 1)
+#define RTC_SEC                0
+#define RTC_MIN                1
+#define RTC_HOUR       2
+#define RTC_DAY                3
+#define RTC_MONTH      4
+#define RTC_YEAR       5
+
+struct da9063_rtc {
+       struct rtc_device       *rtc_dev;
+       struct da9063           *hw;
+       struct rtc_time         alarm_time;
+       bool                    rtc_sync;
+};
+
+static void da9063_data_to_tm(u8 *data, struct rtc_time *tm)
+{
+       tm->tm_sec  = data[RTC_SEC]  & DA9063_COUNT_SEC_MASK;
+       tm->tm_min  = data[RTC_MIN]  & DA9063_COUNT_MIN_MASK;
+       tm->tm_hour = data[RTC_HOUR] & DA9063_COUNT_HOUR_MASK;
+       tm->tm_mday = data[RTC_DAY]  & DA9063_COUNT_DAY_MASK;
+       tm->tm_mon  = MONTHS_FROM_DA9063(data[RTC_MONTH] &
+                                        DA9063_COUNT_MONTH_MASK);
+       tm->tm_year = YEARS_FROM_DA9063(data[RTC_YEAR] &
+                                       DA9063_COUNT_YEAR_MASK);
+}
+
+static void da9063_tm_to_data(struct rtc_time *tm, u8 *data)
+{
+       data[RTC_SEC] &= ~DA9063_COUNT_SEC_MASK;
+       data[RTC_SEC] |= tm->tm_sec & DA9063_COUNT_SEC_MASK;
+
+       data[RTC_MIN] &= ~DA9063_COUNT_MIN_MASK;
+       data[RTC_MIN] |= tm->tm_min & DA9063_COUNT_MIN_MASK;
+
+       data[RTC_HOUR] &= ~DA9063_COUNT_HOUR_MASK;
+       data[RTC_HOUR] |= tm->tm_hour & DA9063_COUNT_HOUR_MASK;
+
+       data[RTC_DAY] &= ~DA9063_COUNT_DAY_MASK;
+       data[RTC_DAY] |= tm->tm_mday & DA9063_COUNT_DAY_MASK;
+
+       data[RTC_MONTH] &= ~DA9063_COUNT_MONTH_MASK;
+       data[RTC_MONTH] |= MONTHS_TO_DA9063(tm->tm_mon) &
+                               DA9063_COUNT_MONTH_MASK;
+
+       data[RTC_YEAR] &= ~DA9063_COUNT_YEAR_MASK;
+       data[RTC_YEAR] |= YEARS_TO_DA9063(tm->tm_year) &
+                               DA9063_COUNT_YEAR_MASK;
+}
+
+static int da9063_rtc_stop_alarm(struct device *dev)
+{
+       struct da9063_rtc *rtc = dev_get_drvdata(dev);
+
+       return regmap_update_bits(rtc->hw->regmap, DA9063_REG_ALARM_Y,
+                                 DA9063_ALARM_ON, 0);
+}
+
+static int da9063_rtc_start_alarm(struct device *dev)
+{
+       struct da9063_rtc *rtc = dev_get_drvdata(dev);
+
+       return regmap_update_bits(rtc->hw->regmap, DA9063_REG_ALARM_Y,
+                                 DA9063_ALARM_ON, DA9063_ALARM_ON);
+}
+
+static int da9063_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+       struct da9063_rtc *rtc = dev_get_drvdata(dev);
+       unsigned long tm_secs;
+       unsigned long al_secs;
+       u8 data[RTC_DATA_LEN];
+       int ret;
+
+       ret = regmap_bulk_read(rtc->hw->regmap, DA9063_REG_COUNT_S,
+                              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] & DA9063_RTC_READ)) {
+               dev_dbg(dev, "RTC not yet ready to be read by the host\n");
+               return -EINVAL;
+       }
+
+       da9063_data_to_tm(data, tm);
+
+       rtc_tm_to_time(tm, &tm_secs);
+       rtc_tm_to_time(&rtc->alarm_time, &al_secs);
+
+       /* handle the rtc synchronisation delay */
+       if (rtc->rtc_sync == true && al_secs - tm_secs == 1)
+               memcpy(tm, &rtc->alarm_time, sizeof(struct rtc_time));
+       else
+               rtc->rtc_sync = false;
+
+       return rtc_valid_tm(tm);
+}
+
+static int da9063_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+       struct da9063_rtc *rtc = dev_get_drvdata(dev);
+       u8 data[RTC_DATA_LEN];
+       int ret;
+
+       da9063_tm_to_data(tm, data);
+       ret = regmap_bulk_write(rtc->hw->regmap, DA9063_REG_COUNT_S,
+                               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_rtc *rtc = dev_get_drvdata(dev);
+       u8 data[RTC_DATA_LEN];
+       int ret;
+       unsigned int val;
+
+       ret = regmap_bulk_read(rtc->hw->regmap, DA9063_REG_ALARM_S,
+                              &data[RTC_SEC], RTC_DATA_LEN);
+       if (ret < 0)
+               return ret;
+
+       da9063_data_to_tm(data, &alrm->time);
+
+       alrm->enabled = !!(data[RTC_YEAR] & DA9063_ALARM_ON);
+
+       ret = regmap_read(rtc->hw->regmap, DA9063_REG_EVENT_A, &val);
+       if (ret < 0)
+               return ret;
+
+       if (val & (DA9063_E_ALARM))
+               alrm->pending = 1;
+       else
+               alrm->pending = 0;
+
+       return 0;
+}
+
+static int da9063_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+       struct da9063_rtc *rtc = dev_get_drvdata(dev);
+       u8 data[RTC_DATA_LEN];
+       int ret;
+
+       da9063_tm_to_data(&alrm->time, data);
+
+       ret = da9063_rtc_stop_alarm(dev);
+       if (ret < 0) {
+               dev_err(dev, "Failed to stop alarm: %d\n", ret);
+               return ret;
+       }
+
+       ret = regmap_bulk_write(rtc->hw->regmap, DA9063_REG_ALARM_S,
+                               data, RTC_DATA_LEN);
+       if (ret < 0) {
+               dev_err(dev, "Failed to write alarm: %d\n", ret);
+               return ret;
+       }
+
+       rtc->alarm_time = alrm->time;
+
+       if (alrm->enabled) {
+               ret = da9063_rtc_start_alarm(dev);
+               if (ret < 0) {
+                       dev_err(dev, "Failed to start alarm: %d\n", ret);
+                       return ret;
+               }
+       }
+
+       return ret;
+}
+
+static int da9063_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+       if (enabled)
+               return da9063_rtc_start_alarm(dev);
+       else
+               return da9063_rtc_stop_alarm(dev);
+}
+
+static irqreturn_t da9063_alarm_event(int irq, void *data)
+{
+       struct da9063_rtc *rtc = data;
+
+       regmap_update_bits(rtc->hw->regmap, DA9063_REG_ALARM_Y,
+                          DA9063_ALARM_ON, 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 *da9063 = dev_get_drvdata(pdev->dev.parent);
+       struct da9063_rtc *rtc;
+       int irq_alarm;
+       u8 data[RTC_DATA_LEN];
+       int ret;
+
+       ret = regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_E,
+                                DA9063_RTC_EN, DA9063_RTC_EN);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "Failed to enable RTC\n");
+               goto err;
+       }
+
+       ret = regmap_update_bits(da9063->regmap, DA9063_REG_EN_32K,
+                                DA9063_CRYSTAL, DA9063_CRYSTAL);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "Failed to run 32kHz oscillator\n");
+               goto err;
+       }
+
+       ret = regmap_update_bits(da9063->regmap, DA9063_REG_ALARM_S,
+                       DA9063_ALARM_STATUS_TICK | DA9063_ALARM_STATUS_ALARM,
+                       0);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
+               goto err;
+       }
+
+       ret = regmap_update_bits(da9063->regmap, DA9063_REG_ALARM_S,
+                                DA9063_ALARM_STATUS_ALARM,
+                                DA9063_ALARM_STATUS_ALARM);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
+               goto err;
+       }
+
+       ret = regmap_update_bits(da9063->regmap, DA9063_REG_ALARM_Y,
+                                DA9063_TICK_ON, 0);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "Failed to disable TICKs\n");
+               goto err;
+       }
+
+       ret = regmap_bulk_read(da9063->regmap, DA9063_REG_ALARM_S,
+                              data, RTC_DATA_LEN);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "Failed to read initial alarm data: %d\n",
+                       ret);
+               goto err;
+       }
+
+       rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
+       if (!rtc)
+               return -ENOMEM;
+
+       platform_set_drvdata(pdev, rtc);
+
+       irq_alarm = platform_get_irq_byname(pdev, "ALARM");
+       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);
+               goto err;
+       }
+
+       rtc->hw = da9063;
+       rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, DA9063_DRVNAME_RTC,
+                                          &da9063_rtc_ops, THIS_MODULE);
+       if (IS_ERR(rtc->rtc_dev))
+               return PTR_ERR(rtc->rtc_dev);
+
+       da9063_data_to_tm(data, &rtc->alarm_time);
+       rtc->rtc_sync = false;
+err:
+       return ret;
+}
+
+static struct platform_driver da9063_rtc_driver = {
+       .probe          = da9063_rtc_probe,
+       .driver         = {
+               .name   = DA9063_DRVNAME_RTC,
+               .owner  = THIS_MODULE,
+       },
+};
+
+module_platform_driver(da9063_rtc_driver);
+
+MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
+MODULE_DESCRIPTION("Real time clock device driver for Dialog DA9063");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DA9063_DRVNAME_RTC);