[PATCH V1 2/2] rtc: da9063: RTC driver

From: Opensource [Steve Twiss]
Date: Thu Mar 06 2014 - 11:52:34 EST


From: Opensource [Steve Twiss] <stwiss.opensource@xxxxxxxxxxx>

Add the RTC driver for DA9063.

Signed-off-by: Opensource [Steve Twiss] <stwiss.opensource@xxxxxxxxxxx>
---
Checks performed with next-20140306/scripts/checkpatch.pl
Kconfig total: 0 errors, 21 warnings, 1344 lines checked
Makefile total: 0 errors, 0 warnings, 139 lines checked
rtc-da9063.c total: 0 errors, 0 warnings, 332 lines checked

Although there are 21 warnings in Kconfig, these do not apply to the
changes made in this patch set.

Change History:

Changes made to this driver since previous RFC V1
Comments by Alessandro Zummo
- http://www.kernelhub.org/?p=2&msg=426327
- Use return PTR_ERR(rtc->rtc_dev); instead of goto err; return err.
- Request the interrupt before the RTC device is registered with the
call to devm_rtc_device_register.

Dependencies:

This driver requires the register changes associated with this patch
set. It requires the changes made to registers.h and in particular,
the new register DA9063_REG_ALARM_S (now appearing at addr=0x46) and
DA9063_ALARM_S_MASK 0x3F are required to allow the triggering of
alarms down to the second resolution level.

This patch applies against kernel version linux-next next-20140306

Regards,
Steve Twiss, Dialog Semiconductor Ltd.



drivers/rtc/Kconfig | 10 ++
drivers/rtc/Makefile | 1 +
drivers/rtc/rtc-da9063.c | 332 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 343 insertions(+)
create mode 100644 drivers/rtc/rtc-da9063.c

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index db933de..472a5b9 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -746,6 +746,16 @@ 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
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index b427bf7..4a4fed9 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -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
index 0000000..d7b15e3
--- /dev/null
+++ b/drivers/rtc/rtc-da9063.c
@@ -0,0 +1,332 @@
+/* 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);
+
+ (void)rtc_tm_to_time(tm, &tm_secs);
+ (void)rtc_tm_to_time(&rtc->alarm_time, &al_secs);
+
+ /* handle the rtc synchronisation delay */
+ if (rtc->rtc_sync == true && al_secs - tm_secs == 1)
+ (void)memcpy((void *)tm, (const void *)&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@xxxxxxxxxxx>");
+MODULE_DESCRIPTION("Real time clock device driver for Dialog DA9063");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DA9063_DRVNAME_RTC);
--
end-of-patch for PATCH V1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/