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authorMallikarjun Kasoju <mkasoju@nvidia.com>2012-08-10 21:52:51 +0530
committerVarun Colbert <vcolbert@nvidia.com>2012-08-14 14:53:27 -0700
commitbe12a19f7f76188681fbb4c9e31b9ee06fe52bfd (patch)
treebc85a79a5280a89110e2155859e9f2e56c09c734 /drivers/rtc
parent8024122d227e2ae4adef0925039b7dc329564571 (diff)
rtc: RTC driver for palmas
Add RTC driver for palmas Bug 978821 Change-Id: I6cdc1f491f97db0edc1c57d2429de565e407d799 Signed-off-by: Mallikarjun Kasoju <mkasoju@nvidia.com> Reviewed-on: http://git-master/r/122126 Reviewed-by: Varun Colbert <vcolbert@nvidia.com> Tested-by: Varun Colbert <vcolbert@nvidia.com>
Diffstat (limited to 'drivers/rtc')
-rw-r--r--drivers/rtc/Kconfig7
-rw-r--r--drivers/rtc/Makefile1
-rw-r--r--drivers/rtc/rtc-palmas.c430
3 files changed, 438 insertions, 0 deletions
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 29eb6d101556..a868ebcbbdff 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -1113,6 +1113,13 @@ config RTC_DRV_TPS80031
This driver can also be built as a module. If so, the module
will be called rtc-tps6591x.
+config RTC_DRV_PALMAS
+ tristate "PALMAS RTC driver"
+ depends on MFD_PALMAS
+ default n
+ help
+ If you say yes here you get support for the PALMAS RTC module.
+
config RTC_DRV_PUV3
tristate "PKUnity v3 RTC support"
depends on ARCH_PUV3
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 3abf7bd2bddd..de49660776c0 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -109,6 +109,7 @@ obj-$(CONFIG_RTC_DRV_TILE) += rtc-tile.o
obj-$(CONFIG_RTC_DRV_TPS6586X) += rtc-tps6586x.o
obj-$(CONFIG_RTC_DRV_TPS6591x) += rtc-tps6591x.o
obj-$(CONFIG_RTC_DRV_TPS80031) += rtc-tps80031.o
+obj-$(CONFIG_RTC_DRV_PALMAS) += rtc-palmas.o
obj-$(CONFIG_RTC_DRV_RC5T583) += rtc-ricoh583.o
obj-$(CONFIG_RTC_DRV_TWL4030) += rtc-twl.o
obj-$(CONFIG_RTC_DRV_TX4939) += rtc-tx4939.o
diff --git a/drivers/rtc/rtc-palmas.c b/drivers/rtc/rtc-palmas.c
new file mode 100644
index 000000000000..d5c963e35f6b
--- /dev/null
+++ b/drivers/rtc/rtc-palmas.c
@@ -0,0 +1,430 @@
+/*
+ * rtc-palmas.c -- Palmas Real Time Clock interface
+ *
+ * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
+ * Author: Kasoju Mallikarjun <mkasoju@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 version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
+ * whether express or implied; 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ * 02111-1307, USA
+ */
+
+#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/palmas.h>
+
+struct palmas_rtc {
+ struct rtc_device *rtc;
+ /* To store the list of enabled interrupts */
+ unsigned int irqstat;
+ unsigned int irq;
+};
+
+/* Total number of RTC registers needed to set time*/
+#define NUM_TIME_REGS (PALMAS_YEARS_REG - PALMAS_SECONDS_REG + 1)
+
+int palmas_rtc_read(struct palmas *palmas, unsigned int reg,
+ unsigned int *dest)
+{
+ unsigned int addr;
+ addr = PALMAS_BASE_TO_REG(PALMAS_RTC_BASE, reg);
+
+ return regmap_read(palmas->regmap[RTC_SLAVE], addr, dest);
+}
+
+int palmas_rtc_write(struct palmas *palmas, unsigned int reg,
+ unsigned int value)
+{
+ unsigned int addr;
+ addr = PALMAS_BASE_TO_REG(PALMAS_RTC_BASE, reg);
+
+ return regmap_write(palmas->regmap[RTC_SLAVE], addr, value);
+}
+
+int palmas_rtc_bulk_read(struct palmas *palmas, unsigned int reg,
+ void *val, size_t val_count)
+{
+ unsigned int addr;
+ addr = PALMAS_BASE_TO_REG(PALMAS_RTC_BASE, reg);
+
+ return regmap_bulk_read(palmas->regmap[RTC_SLAVE], addr,
+ val, val_count);
+}
+
+int palmas_rtc_bulk_write(struct palmas *palmas, unsigned int reg,
+ const void *val, size_t val_count)
+{
+ unsigned int addr;
+ addr = PALMAS_BASE_TO_REG(PALMAS_RTC_BASE, reg);
+
+ return regmap_bulk_write(palmas->regmap[RTC_SLAVE], addr,
+ val, val_count);
+}
+
+int palmas_rtc_update_bits(struct palmas *palmas, unsigned int reg,
+ unsigned int mask, unsigned int val)
+{
+ unsigned int addr;
+ addr = PALMAS_BASE_TO_REG(PALMAS_RTC_BASE, reg);
+
+ return regmap_update_bits(palmas->regmap[RTC_SLAVE], addr, mask, val);
+}
+
+static int palmas_rtc_alarm_irq_enable(struct device *dev, unsigned enabled)
+{
+ struct palmas *palmas = dev_get_drvdata(dev->parent);
+ u8 val = 0;
+
+ if (enabled)
+ val = PALMAS_RTC_INTERRUPTS_REG_IT_ALARM;
+
+ return palmas_rtc_write(palmas,
+ PALMAS_RTC_INTERRUPTS_REG, val);
+}
+
+/*
+ * Gets current palmas 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 palmas_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ unsigned char rtc_data[NUM_TIME_REGS];
+ struct palmas *palmas = dev_get_drvdata(dev->parent);
+ int ret;
+
+ /* Copy RTC counting registers to static registers or latches */
+ ret = palmas_rtc_update_bits(palmas, PALMAS_RTC_CTRL_REG,
+ PALMAS_RTC_CTRL_REG_GET_TIME, PALMAS_RTC_CTRL_REG_GET_TIME);
+ if (ret < 0) {
+ dev_err(dev, "RTC CTRL reg update failed with err:%d\n", ret);
+ return ret;
+ }
+
+ ret = palmas_rtc_bulk_read(palmas, PALMAS_SECONDS_REG,
+ rtc_data, NUM_TIME_REGS);
+ if (ret < 0) {
+ dev_err(dev, "reading from RTC 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_mday = bcd2bin(rtc_data[3]);
+ tm->tm_mon = bcd2bin(rtc_data[4]) - 1;
+ tm->tm_year = bcd2bin(rtc_data[5]) + 100;
+
+ return ret;
+}
+
+static int palmas_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ unsigned char rtc_data[NUM_TIME_REGS];
+ struct palmas *palmas = dev_get_drvdata(dev->parent);
+ 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_mday);
+ rtc_data[4] = bin2bcd(tm->tm_mon + 1);
+ rtc_data[5] = bin2bcd(tm->tm_year - 100);
+
+ /* Stop RTC while updating the RTC time registers */
+ ret = palmas_rtc_update_bits(palmas, PALMAS_RTC_CTRL_REG,
+ PALMAS_RTC_CTRL_REG_STOP_RTC, 0);
+ if (ret < 0) {
+ dev_err(dev, "RTC stop failed with err:%d\n", ret);
+ return ret;
+ }
+
+ /* update all the time registers in one shot */
+ ret = palmas_rtc_bulk_write(palmas, PALMAS_SECONDS_REG,
+ rtc_data, NUM_TIME_REGS);
+ if (ret < 0) {
+ dev_err(dev, "rtc_set_time error %d\n", ret);
+ return ret;
+ }
+
+ /* Start back RTC */
+ ret = palmas_rtc_update_bits(palmas, PALMAS_RTC_CTRL_REG,
+ PALMAS_RTC_CTRL_REG_STOP_RTC, 1);
+ if (ret < 0)
+ dev_err(dev, "RTC start failed with err:%d\n", ret);
+
+ return ret;
+}
+
+/*
+ * Gets current palmas RTC alarm time.
+ */
+static int palmas_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ unsigned char alarm_data[NUM_TIME_REGS];
+ u32 int_val;
+ struct palmas *palmas = dev_get_drvdata(dev->parent);
+ int ret;
+
+ ret = palmas_rtc_bulk_read(palmas, PALMAS_SECONDS_REG,
+ alarm_data, NUM_TIME_REGS);
+ if (ret < 0) {
+ dev_err(dev, "rtc_read_alarm error %d\n", ret);
+ return ret;
+ }
+
+ alm->time.tm_sec = bcd2bin(alarm_data[0]);
+ alm->time.tm_min = bcd2bin(alarm_data[1]);
+ alm->time.tm_hour = bcd2bin(alarm_data[2]);
+ alm->time.tm_mday = bcd2bin(alarm_data[3]);
+ alm->time.tm_mon = bcd2bin(alarm_data[4]) - 1;
+ alm->time.tm_year = bcd2bin(alarm_data[5]) + 100;
+
+ ret = palmas_rtc_read(palmas, PALMAS_RTC_INTERRUPTS_REG,
+ &int_val);
+ if (ret < 0)
+ return ret;
+
+ if (int_val & PALMAS_RTC_INTERRUPTS_REG_IT_ALARM)
+ alm->enabled = 1;
+
+ return ret;
+}
+
+static int palmas_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ unsigned char alarm_data[NUM_TIME_REGS];
+ struct palmas *palmas = dev_get_drvdata(dev->parent);
+ int ret;
+
+ ret = palmas_rtc_alarm_irq_enable(dev, 0);
+ if (ret)
+ return ret;
+
+ alarm_data[0] = bin2bcd(alm->time.tm_sec);
+ alarm_data[1] = bin2bcd(alm->time.tm_min);
+ alarm_data[2] = bin2bcd(alm->time.tm_hour);
+ alarm_data[3] = bin2bcd(alm->time.tm_mday);
+ alarm_data[4] = bin2bcd(alm->time.tm_mon + 1);
+ alarm_data[5] = bin2bcd(alm->time.tm_year - 100);
+
+ /* update all the alarm registers in one shot */
+ ret = palmas_rtc_bulk_write(palmas,
+ PALMAS_ALARM_SECONDS_REG, alarm_data, NUM_TIME_REGS);
+ if (ret) {
+ dev_err(dev, "rtc_set_alarm error %d\n", ret);
+ return ret;
+ }
+
+ if (alm->enabled)
+ ret = palmas_rtc_alarm_irq_enable(dev, 1);
+
+ return ret;
+}
+
+static irqreturn_t palmas_rtc_interrupt(int irq, void *rtc)
+{
+ struct device *dev = rtc;
+ unsigned long events = 0;
+ struct palmas *palmas = dev_get_drvdata(dev->parent);
+ struct palmas_rtc *palmas_rtc = dev_get_drvdata(dev);
+ int ret;
+ u32 rtc_reg;
+
+ ret = palmas_rtc_read(palmas, PALMAS_RTC_STATUS_REG,
+ &rtc_reg);
+ if (ret)
+ return IRQ_NONE;
+
+ if (rtc_reg & PALMAS_RTC_STATUS_REG_ALARM)
+ events = RTC_IRQF | RTC_AF;
+
+ ret = palmas_rtc_write(palmas, PALMAS_RTC_STATUS_REG,
+ rtc_reg);
+ if (ret)
+ return IRQ_NONE;
+
+ /* Notify RTC core on event */
+ rtc_update_irq(palmas_rtc->rtc, 1, events);
+
+ return IRQ_HANDLED;
+}
+
+static struct rtc_class_ops palmas_rtc_ops = {
+ .read_time = palmas_rtc_read_time,
+ .set_time = palmas_rtc_set_time,
+ .read_alarm = palmas_rtc_read_alarm,
+ .set_alarm = palmas_rtc_set_alarm,
+ .alarm_irq_enable = palmas_rtc_alarm_irq_enable,
+};
+
+static int __devinit palmas_rtc_probe(struct platform_device *pdev)
+{
+ struct palmas *palmas = NULL;
+ struct palmas_rtc *palmas_rtc = NULL;
+ int ret;
+ u32 rtc_reg;
+
+ palmas = dev_get_drvdata(pdev->dev.parent);
+
+ palmas_rtc = devm_kzalloc(&pdev->dev, sizeof(struct palmas_rtc),
+ GFP_KERNEL);
+ if (!palmas_rtc) {
+ dev_err(&pdev->dev, "Memory allocation failed.\n");
+ return -ENOMEM;
+ }
+
+ /* Clear pending interrupts */
+ ret = palmas_rtc_read(palmas, PALMAS_RTC_STATUS_REG,
+ &rtc_reg);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "rtc_read_status error %d\n", ret);
+ return ret;
+ }
+
+ ret = palmas_rtc_write(palmas, PALMAS_RTC_STATUS_REG,
+ rtc_reg);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "rtc_clear_interupt error %d\n", ret);
+ return ret;
+ }
+
+ dev_dbg(&pdev->dev, "Enabling palmas-RTC.\n");
+ rtc_reg = PALMAS_RTC_CTRL_REG_STOP_RTC;
+ ret = palmas_rtc_write(palmas, PALMAS_RTC_CTRL_REG,
+ rtc_reg);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "rtc_enable error %d\n", ret);
+ return ret;
+ }
+
+ if (!regmap_irq_chip_get_base(palmas->irq_data))
+ return -EINVAL;
+
+ palmas_rtc->irq = regmap_irq_chip_get_base(palmas->irq_data);
+ if (palmas_rtc->irq <= 0) {
+ dev_err(&pdev->dev, "Wake up is not possible as irq = %d\n",
+ palmas_rtc->irq);
+ return ret;
+ }
+
+ palmas_rtc->irq += PALMAS_RTC_ALARM_IRQ;
+
+ ret = request_threaded_irq(palmas_rtc->irq, NULL,
+ palmas_rtc_interrupt, IRQF_TRIGGER_LOW,
+ "palmas-rtc", &pdev->dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "IRQ is not free.\n");
+ return ret;
+ }
+ device_init_wakeup(&pdev->dev, 1);
+
+ palmas_rtc->rtc = rtc_device_register(pdev->name, &pdev->dev,
+ &palmas_rtc_ops, THIS_MODULE);
+ if (IS_ERR(palmas_rtc->rtc)) {
+ ret = PTR_ERR(palmas_rtc->rtc);
+ free_irq(palmas_rtc->irq, &pdev->dev);
+ dev_err(&pdev->dev, "RTC device register: err %d\n", ret);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, palmas_rtc);
+
+ return 0;
+}
+
+/*
+ * Disable all palmas RTC module interrupts.
+ * Sets status flag to free.
+ */
+static int __devexit palmas_rtc_remove(struct platform_device *pdev)
+{
+ /* leave rtc running, but disable irqs */
+ struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
+
+ palmas_rtc_alarm_irq_enable(&palmas->rtc->rtc->dev, 0);
+ free_irq(palmas->irq, &pdev->dev);
+ rtc_device_unregister(palmas->rtc->rtc);
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int palmas_rtc_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
+ u8 alarm = PALMAS_RTC_INTERRUPTS_REG_IT_ALARM;
+ int ret;
+
+ if (device_may_wakeup(dev))
+ enable_irq_wake(palmas->rtc->irq);
+
+ /* Store current list of enabled interrupts*/
+ ret = palmas_rtc_read(palmas, PALMAS_RTC_INTERRUPTS_REG,
+ &palmas->rtc->irqstat);
+ if (ret < 0)
+ return ret;
+
+ /* Enable RTC ALARM interrupt only */
+ return palmas_rtc_write(palmas,
+ PALMAS_RTC_INTERRUPTS_REG, alarm);
+}
+
+static int palmas_rtc_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
+
+ if (device_may_wakeup(dev))
+ disable_irq_wake(palmas->rtc->irq);
+
+ /* Restore list of enabled interrupts before suspend */
+ return palmas_rtc_write(palmas,
+ PALMAS_RTC_INTERRUPTS_REG, palmas->rtc->irqstat);
+}
+
+static const struct dev_pm_ops palmas_rtc_pm_ops = {
+ .suspend = palmas_rtc_suspend,
+ .resume = palmas_rtc_resume,
+};
+
+#define DEV_PM_OPS (&palmas_rtc_pm_ops)
+#else
+#define DEV_PM_OPS NULL
+#endif
+
+static struct platform_driver palmas_rtc_driver = {
+ .probe = palmas_rtc_probe,
+ .remove = __devexit_p(palmas_rtc_remove),
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "palmas-rtc",
+ .pm = DEV_PM_OPS,
+ },
+};
+
+module_platform_driver(palmas_rtc_driver);
+MODULE_ALIAS("platform:palmas_rtc");
+MODULE_AUTHOR("Kasoju Mallikarjun <mkasoju@nvidia.com>");
+MODULE_LICENSE("GPL v2");