[PATCH V1 1/2] gpio: Add gpio driver for RICOH PMIC RC5T583

[Laxman Dewangan <ldewangan@nvidia.com>]

The PMIC device RC5T583 from RICOH supports 8 gpios.
Adding gpio driver for this device to access the pins
control through gpio library.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
---
 drivers/gpio/Kconfig        |    9 +++
 drivers/gpio/Makefile       |    1 +
 drivers/gpio/gpio-rc5t583.c |  148 +++++++++++++++++++++++++++++++++++++++++++
 include/linux/mfd/rc5t583.h |   11 +++
 4 files changed, 169 insertions(+), 0 deletions(-)
 create mode 100644 drivers/gpio/gpio-rc5t583.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index e03653d..4e1bd9e 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -288,6 +288,15 @@ config GPIO_PCF857X
 	  This driver provides an in-kernel interface to those GPIOs using
 	  platform-neutral GPIO calls.
 
+config GPIO_RC5T583
+	bool "RICOH RC5T583 GPIO"
+	depends on MFD_RC5T583
+	help
+	  Select this option to enable GPIO driver for the Ricoh RC5T583
+	  chip family.
+	  This driver provides the support for driving/reading the gpio pins
+	  of RC5T583 device through standard gpio library.
+
 config GPIO_SX150X
 	bool "Semtech SX150x I2C GPIO expander"
 	depends on I2C=y
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 007f54b..a27bf53 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -43,6 +43,7 @@ obj-$(CONFIG_GPIO_PCF857X)	+= gpio-pcf857x.o
 obj-$(CONFIG_GPIO_PCH)		+= gpio-pch.o
 obj-$(CONFIG_GPIO_PL061)	+= gpio-pl061.o
 obj-$(CONFIG_GPIO_PXA)		+= gpio-pxa.o
+obj-$(CONFIG_GPIO_RC5T583)	+= gpio-rc5t583.o
 obj-$(CONFIG_GPIO_RDC321X)	+= gpio-rdc321x.o
 obj-$(CONFIG_PLAT_SAMSUNG)	+= gpio-samsung.o
 obj-$(CONFIG_ARCH_SA1100)	+= gpio-sa1100.o
diff --git a/drivers/gpio/gpio-rc5t583.c b/drivers/gpio/gpio-rc5t583.c
new file mode 100644
index 0000000..6e3563b
--- /dev/null
+++ b/drivers/gpio/gpio-rc5t583.c
@@ -0,0 +1,148 @@
+/*
+ * GPIO driver for RICOH583 power management chip.
+ *
+ * Copyright (c) 2011-2012, NVIDIA CORPORATION.  All rights reserved.
+ * Author: Laxman dewangan <ldewangan@nvidia.com>
+ *
+ * Based on code
+ *	Copyright (C) 2011 RICOH COMPANY,LTD
+ *
+ * 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/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/gpio.h>
+#include <linux/mfd/rc5t583.h>
+
+static int rc5t583_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+	struct rc5t583 *rc5t583 = dev_get_drvdata(chip->dev);
+	uint8_t val;
+	int ret;
+
+	ret = rc5t583_read(rc5t583->dev, RC5T583_GPIO_MON_IOIN, &val);
+	if (ret < 0)
+		return ret;
+
+	return !!(val & BIT(offset));
+}
+
+static void rc5t583_gpio_set(struct gpio_chip *chip, unsigned int offset,
+			int value)
+{
+	struct rc5t583 *rc5t583 = dev_get_drvdata(chip->dev);
+	if (value)
+		rc5t583_set_bits(rc5t583->dev, RC5T583_GPIO_IOOUT, BIT(offset));
+	else
+		rc5t583_clear_bits(rc5t583->dev, RC5T583_GPIO_IOOUT,
+					BIT(offset));
+}
+
+static int rc5t583_gpio_input(struct gpio_chip *chip, unsigned int offset)
+{
+	struct rc5t583 *rc5t583 = dev_get_drvdata(chip->dev);
+	return rc5t583_clear_bits(rc5t583->dev, RC5T583_GPIO_IOSEL,
+					BIT(offset));
+}
+
+static int rc5t583_gpio_output(struct gpio_chip *chip, unsigned offset,
+				int value)
+{
+	struct rc5t583 *rc5t583 = dev_get_drvdata(chip->dev);
+	rc5t583_gpio_set(chip, offset, value);
+	return rc5t583_set_bits(rc5t583->dev, RC5T583_GPIO_IOSEL, BIT(offset));
+}
+
+static int rc5t583_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+	struct rc5t583 *rc5t583 = dev_get_drvdata(chip->dev);
+	if ((offset >= 0) && (offset < 8))
+		return rc5t583->irq_base + RC5T583_IRQ_GPIO0 + offset;
+	return -EINVAL;
+}
+
+static int rc5t583_gpio_request(struct gpio_chip *chip, unsigned offset)
+{
+	struct rc5t583 *rc5t583 = dev_get_drvdata(chip->dev);
+	return rc5t583_clear_bits(rc5t583->dev, RC5T583_GPIO_PGSEL,
+					BIT(offset));
+}
+
+static void rc5t583_gpio_free(struct gpio_chip *chip, unsigned offset)
+{
+	struct rc5t583 *rc5t583 = dev_get_drvdata(chip->dev);
+	rc5t583_set_bits(rc5t583->dev, RC5T583_GPIO_PGSEL, BIT(offset));
+}
+
+void rc5t583_gpio_init(struct rc5t583 *rc5t583,
+			struct rc5t583_platform_data *pdata)
+{
+	int ret;
+	int i;
+
+	if (!pdata || pdata->gpio_base  <= 0)
+		return;
+
+	rc5t583->gpio_chip = devm_kzalloc(rc5t583->dev,
+				sizeof(struct gpio_chip), GFP_KERNEL);
+	if (!rc5t583->gpio_chip) {
+		dev_warn(rc5t583->dev,
+			"%s(): Memory allocation error\n", __func__);
+		return;
+	}
+
+	rc5t583->gpio_chip->label		= "gpio-rc5t583",
+	rc5t583->gpio_chip->owner		= THIS_MODULE,
+	rc5t583->gpio_chip->request		= rc5t583_gpio_request,
+	rc5t583->gpio_chip->free		= rc5t583_gpio_free,
+	rc5t583->gpio_chip->direction_input	= rc5t583_gpio_input,
+	rc5t583->gpio_chip->direction_output	= rc5t583_gpio_output,
+	rc5t583->gpio_chip->set			= rc5t583_gpio_set,
+	rc5t583->gpio_chip->get			= rc5t583_gpio_get,
+	rc5t583->gpio_chip->to_irq		= rc5t583_gpio_to_irq,
+	rc5t583->gpio_chip->ngpio		= RC5T583_MAX_GPIO,
+	rc5t583->gpio_chip->can_sleep		= 1,
+	rc5t583->gpio_chip->dev			= rc5t583->dev;
+	rc5t583->gpio_chip->base		= pdata->gpio_base;
+
+	for (i = 0; i < RC5T583_MAX_GPIO; ++i) {
+		if (pdata->gpio_enable_pulldn[i])
+			ret = rc5t583_set_bits(rc5t583->dev,
+					RC5T583_GPIO_PDEN, BIT(i));
+		else
+			ret = rc5t583_clear_bits(rc5t583->dev,
+					RC5T583_GPIO_PDEN, BIT(i));
+		if (ret < 0)
+			goto end;
+
+		if (pdata->gpio_init_flag[i] & GPIOF_IN)
+			ret = rc5t583_gpio_input(rc5t583->gpio_chip, i);
+		else
+			ret = rc5t583_gpio_output(rc5t583->gpio_chip, i,
+				!!(pdata->gpio_init_flag[i] & GPIOF_INIT_HIGH));
+		if (ret < 0)
+			goto end;
+
+		ret = rc5t583_clear_bits(rc5t583->dev, RC5T583_GPIO_PGSEL,
+						BIT(i));
+		if (ret < 0)
+			goto end;
+	}
+
+	ret = gpiochip_add(rc5t583->gpio_chip);
+end:
+	if (ret < 0)
+		dev_warn(rc5t583->dev, "GPIO registration failed: %d\n", ret);
+}
diff --git a/include/linux/mfd/rc5t583.h b/include/linux/mfd/rc5t583.h
index a2c6160..7922112 100644
--- a/include/linux/mfd/rc5t583.h
+++ b/include/linux/mfd/rc5t583.h
@@ -252,6 +252,8 @@ enum {
 struct rc5t583 {
 	struct device	*dev;
 	struct regmap	*regmap;
+	int		gpio_base;
+	struct gpio_chip *gpio_chip;
 	int		chip_irq;
 	int		irq_base;
 	struct mutex	irq_lock;
@@ -270,13 +272,20 @@ struct rc5t583 {
 /*
  * rc5t583_platform_data: Platform data for ricoh rc5t583 pmu.
  * The board specific data is provided through this structure.
+ * @gpio_base: Gpio base number on which device starts its gpio.
  * @irq_base: Irq base number on which this device registers their interrupts.
  * @enable_shutdown: Enable shutdown through the input pin "shutdown".
+ * @gpio_enable_pulldn: Enable internal pull down of gpios.
+ * @gpio_init_flag: Initial gpio flag which need to be configure during gpio
+ *		registration.
  */
 
 struct rc5t583_platform_data {
+	int		gpio_base;
 	int		irq_base;
 	bool		enable_shutdown;
+	bool		gpio_enable_pulldn[RC5T583_MAX_GPIO];
+	unsigned int	gpio_init_flag[RC5T583_MAX_GPIO];
 };
 
 int rc5t583_write(struct device *dev, u8 reg, uint8_t val);
@@ -289,6 +298,8 @@ int rc5t583_update(struct device *dev, unsigned int reg,
 		unsigned int val, unsigned int mask);
 int rc5t583_ext_power_req_config(struct device *dev, int deepsleep_id,
 	int ext_pwr_req, int deepsleep_slot_nr);
+void rc5t583_gpio_init(struct rc5t583 *rc5t583,
+			struct rc5t583_platform_data *pdata);
 int rc5t583_irq_init(struct rc5t583 *rc5t583, int irq, int irq_base);
 int rc5t583_irq_exit(struct rc5t583 *rc5t583);
 
-- 
1.7.1.1