drivers/rtc/rtc-as3722: add RTC driver
The ams AS3722 is a compact system PMU suitable for mobile phones, tablets
etc.
Add a driver to support accessing the RTC found on the ams AS3722 PMIC
using RTC framework.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Florian Lobmaier <florian.lobmaier@ams.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rtc/rtc-as3722.c b/drivers/rtc/rtc-as3722.c
new file mode 100644
index 0000000..9cfa817
--- /dev/null
+++ b/drivers/rtc/rtc-as3722.c
@@ -0,0 +1,275 @@
+/*
+ * rtc-as3722.c - Real Time Clock driver for ams AS3722 PMICs
+ *
+ * Copyright (C) 2013 ams AG
+ * Copyright (c) 2013, NVIDIA Corporation. All rights reserved.
+ *
+ * Author: Florian Lobmaier <florian.lobmaier@ams.com>
+ * Author: Laxman Dewangan <ldewangan@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ */
+
+#include <linux/bcd.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/ioctl.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mfd/as3722.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/time.h>
+
+#define AS3722_RTC_START_YEAR 2000
+struct as3722_rtc {
+ struct rtc_device *rtc;
+ struct device *dev;
+ struct as3722 *as3722;
+ int alarm_irq;
+ bool irq_enable;
+};
+
+static void as3722_time_to_reg(u8 *rbuff, struct rtc_time *tm)
+{
+ rbuff[0] = bin2bcd(tm->tm_sec);
+ rbuff[1] = bin2bcd(tm->tm_min);
+ rbuff[2] = bin2bcd(tm->tm_hour);
+ rbuff[3] = bin2bcd(tm->tm_mday);
+ rbuff[4] = bin2bcd(tm->tm_mon);
+ rbuff[5] = bin2bcd(tm->tm_year - (AS3722_RTC_START_YEAR - 1900));
+}
+
+static void as3722_reg_to_time(u8 *rbuff, struct rtc_time *tm)
+{
+ tm->tm_sec = bcd2bin(rbuff[0] & 0x7F);
+ tm->tm_min = bcd2bin(rbuff[1] & 0x7F);
+ tm->tm_hour = bcd2bin(rbuff[2] & 0x3F);
+ tm->tm_mday = bcd2bin(rbuff[3] & 0x3F);
+ tm->tm_mon = bcd2bin(rbuff[4] & 0x1F);
+ tm->tm_year = (AS3722_RTC_START_YEAR - 1900) + bcd2bin(rbuff[5] & 0x7F);
+ return;
+}
+
+static int as3722_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct as3722_rtc *as3722_rtc = dev_get_drvdata(dev);
+ struct as3722 *as3722 = as3722_rtc->as3722;
+ u8 as_time_array[6];
+ int ret;
+
+ ret = as3722_block_read(as3722, AS3722_RTC_SECOND_REG,
+ 6, as_time_array);
+ if (ret < 0) {
+ dev_err(dev, "RTC_SECOND reg block read failed %d\n", ret);
+ return ret;
+ }
+ as3722_reg_to_time(as_time_array, tm);
+ return 0;
+}
+
+static int as3722_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct as3722_rtc *as3722_rtc = dev_get_drvdata(dev);
+ struct as3722 *as3722 = as3722_rtc->as3722;
+ u8 as_time_array[6];
+ int ret;
+
+ if (tm->tm_year < (AS3722_RTC_START_YEAR - 1900))
+ return -EINVAL;
+
+ as3722_time_to_reg(as_time_array, tm);
+ ret = as3722_block_write(as3722, AS3722_RTC_SECOND_REG, 6,
+ as_time_array);
+ if (ret < 0)
+ dev_err(dev, "RTC_SECOND reg block write failed %d\n", ret);
+ return ret;
+}
+
+static int as3722_rtc_alarm_irq_enable(struct device *dev,
+ unsigned int enabled)
+{
+ struct as3722_rtc *as3722_rtc = dev_get_drvdata(dev);
+
+ if (enabled && !as3722_rtc->irq_enable) {
+ enable_irq(as3722_rtc->alarm_irq);
+ as3722_rtc->irq_enable = true;
+ } else if (!enabled && as3722_rtc->irq_enable) {
+ disable_irq(as3722_rtc->alarm_irq);
+ as3722_rtc->irq_enable = false;
+ }
+ return 0;
+}
+
+static int as3722_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct as3722_rtc *as3722_rtc = dev_get_drvdata(dev);
+ struct as3722 *as3722 = as3722_rtc->as3722;
+ u8 as_time_array[6];
+ int ret;
+
+ ret = as3722_block_read(as3722, AS3722_RTC_ALARM_SECOND_REG, 6,
+ as_time_array);
+ if (ret < 0) {
+ dev_err(dev, "RTC_ALARM_SECOND block read failed %d\n", ret);
+ return ret;
+ }
+
+ as3722_reg_to_time(as_time_array, &alrm->time);
+ return 0;
+}
+
+static int as3722_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct as3722_rtc *as3722_rtc = dev_get_drvdata(dev);
+ struct as3722 *as3722 = as3722_rtc->as3722;
+ u8 as_time_array[6];
+ int ret;
+
+ if (alrm->time.tm_year < (AS3722_RTC_START_YEAR - 1900))
+ return -EINVAL;
+
+ ret = as3722_rtc_alarm_irq_enable(dev, 0);
+ if (ret < 0) {
+ dev_err(dev, "Disable RTC alarm failed\n");
+ return ret;
+ }
+
+ as3722_time_to_reg(as_time_array, &alrm->time);
+ ret = as3722_block_write(as3722, AS3722_RTC_ALARM_SECOND_REG, 6,
+ as_time_array);
+ if (ret < 0) {
+ dev_err(dev, "RTC_ALARM_SECOND block write failed %d\n", ret);
+ return ret;
+ }
+
+ if (alrm->enabled)
+ ret = as3722_rtc_alarm_irq_enable(dev, alrm->enabled);
+ return ret;
+}
+
+static irqreturn_t as3722_alarm_irq(int irq, void *data)
+{
+ struct as3722_rtc *as3722_rtc = data;
+
+ rtc_update_irq(as3722_rtc->rtc, 1, RTC_IRQF | RTC_AF);
+ return IRQ_HANDLED;
+}
+
+static const struct rtc_class_ops as3722_rtc_ops = {
+ .read_time = as3722_rtc_read_time,
+ .set_time = as3722_rtc_set_time,
+ .read_alarm = as3722_rtc_read_alarm,
+ .set_alarm = as3722_rtc_set_alarm,
+ .alarm_irq_enable = as3722_rtc_alarm_irq_enable,
+};
+
+static int as3722_rtc_probe(struct platform_device *pdev)
+{
+ struct as3722 *as3722 = dev_get_drvdata(pdev->dev.parent);
+ struct as3722_rtc *as3722_rtc;
+ int ret;
+
+ as3722_rtc = devm_kzalloc(&pdev->dev, sizeof(*as3722_rtc), GFP_KERNEL);
+ if (!as3722_rtc)
+ return -ENOMEM;
+
+ as3722_rtc->as3722 = as3722;
+ as3722_rtc->dev = &pdev->dev;
+ platform_set_drvdata(pdev, as3722_rtc);
+
+ /* Enable the RTC to make sure it is running. */
+ ret = as3722_update_bits(as3722, AS3722_RTC_CONTROL_REG,
+ AS3722_RTC_ON | AS3722_RTC_ALARM_WAKEUP_EN,
+ AS3722_RTC_ON | AS3722_RTC_ALARM_WAKEUP_EN);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "RTC_CONTROL reg write failed: %d\n", ret);
+ return ret;
+ }
+
+ device_init_wakeup(&pdev->dev, 1);
+
+ as3722_rtc->rtc = rtc_device_register("as3722", &pdev->dev,
+ &as3722_rtc_ops, THIS_MODULE);
+ if (IS_ERR(as3722_rtc->rtc)) {
+ ret = PTR_ERR(as3722_rtc->rtc);
+ dev_err(&pdev->dev, "RTC register failed: %d\n", ret);
+ return ret;
+ }
+
+ as3722_rtc->alarm_irq = platform_get_irq(pdev, 0);
+ dev_info(&pdev->dev, "RTC interrupt %d\n", as3722_rtc->alarm_irq);
+
+ ret = request_threaded_irq(as3722_rtc->alarm_irq, NULL,
+ as3722_alarm_irq, IRQF_ONESHOT | IRQF_EARLY_RESUME,
+ "rtc-alarm", as3722_rtc);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to request alarm IRQ %d: %d\n",
+ as3722_rtc->alarm_irq, ret);
+ goto scrub;
+ }
+ disable_irq(as3722_rtc->alarm_irq);
+ return 0;
+scrub:
+ rtc_device_unregister(as3722_rtc->rtc);
+ return ret;
+}
+
+static int as3722_rtc_remove(struct platform_device *pdev)
+{
+ struct as3722_rtc *as3722_rtc = platform_get_drvdata(pdev);
+
+ free_irq(as3722_rtc->alarm_irq, as3722_rtc);
+ rtc_device_unregister(as3722_rtc->rtc);
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int as3722_rtc_suspend(struct device *dev)
+{
+ struct as3722_rtc *as3722_rtc = dev_get_drvdata(dev);
+
+ if (device_may_wakeup(dev))
+ enable_irq_wake(as3722_rtc->alarm_irq);
+
+ return 0;
+}
+
+static int as3722_rtc_resume(struct device *dev)
+{
+ struct as3722_rtc *as3722_rtc = dev_get_drvdata(dev);
+
+ if (device_may_wakeup(dev))
+ disable_irq_wake(as3722_rtc->alarm_irq);
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops as3722_rtc_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(as3722_rtc_suspend, as3722_rtc_resume)
+};
+
+static struct platform_driver as3722_rtc_driver = {
+ .probe = as3722_rtc_probe,
+ .remove = as3722_rtc_remove,
+ .driver = {
+ .name = "as3722-rtc",
+ .pm = &as3722_rtc_pm_ops,
+ },
+};
+module_platform_driver(as3722_rtc_driver);
+
+MODULE_DESCRIPTION("RTC driver for AS3722 PMICs");
+MODULE_ALIAS("platform:as3722-rtc");
+MODULE_AUTHOR("Florian Lobmaier <florian.lobmaier@ams.com>");
+MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
+MODULE_LICENSE("GPL");