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authorVenu Byravarasu <vbyravarasu@nvidia.com>2012-10-04 17:14:04 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-06 03:05:03 +0900
commit90829c089ef622e54ce1153eb6dcda9ce98cb7c2 (patch)
treed6468baa51657219d583d0cf721bfd845d046bc4 /drivers/rtc/rtc-rc5t583.c
parenta16e8393ac03cc24fd9b838f42823b4242ceac88 (diff)
rtc: rc5t583: add ricoh rc5t583 RTC driver
Add an RTC driver for the RTC device on Ricoh MFD Rc5t583. Ricoh RTC has 3 types of alarms. The current patch adds support for the Y-Alarm of RC5t583 RTC. Signed-off-by: Venu Byravarasu <vbyravarasu@nvidia.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/rtc/rtc-rc5t583.c')
-rw-r--r--drivers/rtc/rtc-rc5t583.c331
1 files changed, 331 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-rc5t583.c b/drivers/rtc/rtc-rc5t583.c
new file mode 100644
index 000000000000..cdb140c29c56
--- /dev/null
+++ b/drivers/rtc/rtc-rc5t583.c
@@ -0,0 +1,331 @@
+/*
+ * rtc-rc5t583.c -- RICOH RC5T583 Real Time Clock
+ *
+ * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
+ * Author: Venu Byravarasu <vbyravarasu@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/rtc.h>
+#include <linux/bcd.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/rc5t583.h>
+
+struct rc5t583_rtc {
+ struct rtc_device *rtc;
+ /* To store the list of enabled interrupts, during system suspend */
+ u32 irqen;
+};
+
+/* Total number of RTC registers needed to set time*/
+#define NUM_TIME_REGS (RC5T583_RTC_YEAR - RC5T583_RTC_SEC + 1)
+
+/* Total number of RTC registers needed to set Y-Alarm*/
+#define NUM_YAL_REGS (RC5T583_RTC_AY_YEAR - RC5T583_RTC_AY_MIN + 1)
+
+/* Set Y-Alarm interrupt */
+#define SET_YAL BIT(5)
+
+/* Get Y-Alarm interrupt status*/
+#define GET_YAL_STATUS BIT(3)
+
+static int rc5t583_rtc_alarm_irq_enable(struct device *dev, unsigned enabled)
+{
+ struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
+ u8 val;
+
+ /* Set Y-Alarm, based on 'enabled' */
+ val = enabled ? SET_YAL : 0;
+
+ return regmap_update_bits(rc5t583->regmap, RC5T583_RTC_CTL1, SET_YAL,
+ val);
+}
+
+/*
+ * Gets current rc5t583 RTC time and date parameters.
+ *
+ * The RTC's time/alarm representation is not what gmtime(3) requires
+ * Linux to use:
+ *
+ * - Months are 1..12 vs Linux 0-11
+ * - Years are 0..99 vs Linux 1900..N (we assume 21st century)
+ */
+static int rc5t583_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
+ u8 rtc_data[NUM_TIME_REGS];
+ int ret;
+
+ ret = regmap_bulk_read(rc5t583->regmap, RC5T583_RTC_SEC, rtc_data,
+ NUM_TIME_REGS);
+ if (ret < 0) {
+ dev_err(dev, "RTC read time failed with err:%d\n", ret);
+ return ret;
+ }
+
+ tm->tm_sec = bcd2bin(rtc_data[0]);
+ tm->tm_min = bcd2bin(rtc_data[1]);
+ tm->tm_hour = bcd2bin(rtc_data[2]);
+ tm->tm_wday = bcd2bin(rtc_data[3]);
+ tm->tm_mday = bcd2bin(rtc_data[4]);
+ tm->tm_mon = bcd2bin(rtc_data[5]) - 1;
+ tm->tm_year = bcd2bin(rtc_data[6]) + 100;
+
+ return ret;
+}
+
+static int rc5t583_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
+ unsigned char rtc_data[NUM_TIME_REGS];
+ int ret;
+
+ rtc_data[0] = bin2bcd(tm->tm_sec);
+ rtc_data[1] = bin2bcd(tm->tm_min);
+ rtc_data[2] = bin2bcd(tm->tm_hour);
+ rtc_data[3] = bin2bcd(tm->tm_wday);
+ rtc_data[4] = bin2bcd(tm->tm_mday);
+ rtc_data[5] = bin2bcd(tm->tm_mon + 1);
+ rtc_data[6] = bin2bcd(tm->tm_year - 100);
+
+ ret = regmap_bulk_write(rc5t583->regmap, RC5T583_RTC_SEC, rtc_data,
+ NUM_TIME_REGS);
+ if (ret < 0) {
+ dev_err(dev, "RTC set time failed with error %d\n", ret);
+ return ret;
+ }
+
+ return ret;
+}
+
+static int rc5t583_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
+ unsigned char alarm_data[NUM_YAL_REGS];
+ u32 interrupt_enable;
+ int ret;
+
+ ret = regmap_bulk_read(rc5t583->regmap, RC5T583_RTC_AY_MIN, alarm_data,
+ NUM_YAL_REGS);
+ if (ret < 0) {
+ dev_err(dev, "rtc_read_alarm error %d\n", ret);
+ return ret;
+ }
+
+ alm->time.tm_min = bcd2bin(alarm_data[0]);
+ alm->time.tm_hour = bcd2bin(alarm_data[1]);
+ alm->time.tm_mday = bcd2bin(alarm_data[2]);
+ alm->time.tm_mon = bcd2bin(alarm_data[3]) - 1;
+ alm->time.tm_year = bcd2bin(alarm_data[4]) + 100;
+
+ ret = regmap_read(rc5t583->regmap, RC5T583_RTC_CTL1, &interrupt_enable);
+ if (ret < 0)
+ return ret;
+
+ /* check if YALE is set */
+ if (interrupt_enable & SET_YAL)
+ alm->enabled = 1;
+
+ return ret;
+}
+
+static int rc5t583_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
+ unsigned char alarm_data[NUM_YAL_REGS];
+ int ret;
+
+ ret = rc5t583_rtc_alarm_irq_enable(dev, 0);
+ if (ret)
+ return ret;
+
+ alarm_data[0] = bin2bcd(alm->time.tm_min);
+ alarm_data[1] = bin2bcd(alm->time.tm_hour);
+ alarm_data[2] = bin2bcd(alm->time.tm_mday);
+ alarm_data[3] = bin2bcd(alm->time.tm_mon + 1);
+ alarm_data[4] = bin2bcd(alm->time.tm_year - 100);
+
+ ret = regmap_bulk_write(rc5t583->regmap, RC5T583_RTC_AY_MIN, alarm_data,
+ NUM_YAL_REGS);
+ if (ret) {
+ dev_err(dev, "rtc_set_alarm error %d\n", ret);
+ return ret;
+ }
+
+ if (alm->enabled)
+ ret = rc5t583_rtc_alarm_irq_enable(dev, 1);
+
+ return ret;
+}
+
+static irqreturn_t rc5t583_rtc_interrupt(int irq, void *rtc)
+{
+ struct device *dev = rtc;
+ struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
+ struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev);
+ unsigned long events = 0;
+ int ret;
+ u32 rtc_reg;
+
+ ret = regmap_read(rc5t583->regmap, RC5T583_RTC_CTL2, &rtc_reg);
+ if (ret < 0)
+ return IRQ_NONE;
+
+ if (rtc_reg & GET_YAL_STATUS) {
+ events = RTC_IRQF | RTC_AF;
+ /* clear pending Y-alarm interrupt bit */
+ rtc_reg &= ~GET_YAL_STATUS;
+ }
+
+ ret = regmap_write(rc5t583->regmap, RC5T583_RTC_CTL2, rtc_reg);
+ if (ret)
+ return IRQ_NONE;
+
+ /* Notify RTC core on event */
+ rtc_update_irq(rc5t583_rtc->rtc, 1, events);
+
+ return IRQ_HANDLED;
+}
+
+static const struct rtc_class_ops rc5t583_rtc_ops = {
+ .read_time = rc5t583_rtc_read_time,
+ .set_time = rc5t583_rtc_set_time,
+ .read_alarm = rc5t583_rtc_read_alarm,
+ .set_alarm = rc5t583_rtc_set_alarm,
+ .alarm_irq_enable = rc5t583_rtc_alarm_irq_enable,
+};
+
+static int __devinit rc5t583_rtc_probe(struct platform_device *pdev)
+{
+ struct rc5t583 *rc5t583 = dev_get_drvdata(pdev->dev.parent);
+ struct rc5t583_rtc *ricoh_rtc;
+ struct rc5t583_platform_data *pmic_plat_data;
+ int ret;
+ int irq;
+
+ ricoh_rtc = devm_kzalloc(&pdev->dev, sizeof(struct rc5t583_rtc),
+ GFP_KERNEL);
+ if (!ricoh_rtc)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, ricoh_rtc);
+
+ /* Clear pending interrupts */
+ ret = regmap_write(rc5t583->regmap, RC5T583_RTC_CTL2, 0);
+ if (ret < 0)
+ return ret;
+
+ /* clear RTC Adjust register */
+ ret = regmap_write(rc5t583->regmap, RC5T583_RTC_ADJ, 0);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "unable to program rtc_adjust reg\n");
+ return -EBUSY;
+ }
+
+ pmic_plat_data = dev_get_platdata(rc5t583->dev);
+ irq = pmic_plat_data->irq_base;
+ if (irq <= 0) {
+ dev_warn(&pdev->dev, "Wake up is not possible as irq = %d\n",
+ irq);
+ return ret;
+ }
+
+ irq += RC5T583_IRQ_YALE;
+ ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
+ rc5t583_rtc_interrupt, IRQF_TRIGGER_LOW,
+ "rtc-rc5t583", &pdev->dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "IRQ is not free.\n");
+ return ret;
+ }
+ device_init_wakeup(&pdev->dev, 1);
+
+ ricoh_rtc->rtc = rtc_device_register(pdev->name, &pdev->dev,
+ &rc5t583_rtc_ops, THIS_MODULE);
+ if (IS_ERR(ricoh_rtc->rtc)) {
+ ret = PTR_ERR(ricoh_rtc->rtc);
+ dev_err(&pdev->dev, "RTC device register: err %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+/*
+ * Disable rc5t583 RTC interrupts.
+ * Sets status flag to free.
+ */
+static int __devexit rc5t583_rtc_remove(struct platform_device *pdev)
+{
+ struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(&pdev->dev);
+
+ rc5t583_rtc_alarm_irq_enable(&rc5t583_rtc->rtc->dev, 0);
+
+ rtc_device_unregister(rc5t583_rtc->rtc);
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+
+static int rc5t583_rtc_suspend(struct device *dev)
+{
+ struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
+ struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev);
+ int ret;
+
+ /* Store current list of enabled interrupts*/
+ ret = regmap_read(rc5t583->regmap, RC5T583_RTC_CTL1,
+ &rc5t583_rtc->irqen);
+ return ret;
+}
+
+static int rc5t583_rtc_resume(struct device *dev)
+{
+ struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
+ struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev);
+
+ /* Restore list of enabled interrupts before suspend */
+ return regmap_write(rc5t583->regmap, RC5T583_RTC_CTL1,
+ rc5t583_rtc->irqen);
+}
+
+static const struct dev_pm_ops rc5t583_rtc_pm_ops = {
+ .suspend = rc5t583_rtc_suspend,
+ .resume = rc5t583_rtc_resume,
+};
+
+#define DEV_PM_OPS (&rc5t583_rtc_pm_ops)
+#else
+#define DEV_PM_OPS NULL
+#endif
+
+static struct platform_driver rc5t583_rtc_driver = {
+ .probe = rc5t583_rtc_probe,
+ .remove = __devexit_p(rc5t583_rtc_remove),
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "rtc-rc5t583",
+ .pm = DEV_PM_OPS,
+ },
+};
+
+module_platform_driver(rc5t583_rtc_driver);
+MODULE_ALIAS("platform:rtc-rc5t583");
+MODULE_AUTHOR("Venu Byravarasu <vbyravarasu@nvidia.com>");
+MODULE_LICENSE("GPL v2");