GPIO: DA9052 GPIO module v3

DA9052 PMIC has 16 bit GPIO bus for peripheral control.

This patch add support for the GPIO pins on the DA9052.

Signed-off-by: David Dajun Chen <dchen@diasemi.com>
Signed-off-by: Ashish Jangam <ashish.jangam@kpitcummins.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/drivers/gpio/gpio-da9052.c b/drivers/gpio/gpio-da9052.c
new file mode 100644
index 0000000..c23761f
--- /dev/null
+++ b/drivers/gpio/gpio-da9052.c
@@ -0,0 +1,278 @@
+/*
+ * GPIO Driver for Dialog DA9052 PMICs.
+ *
+ * Copyright(c) 2011 Dialog Semiconductor Ltd.
+ *
+ * Author: David Dajun Chen <dchen@diasemi.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.
+ *
+ */
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/uaccess.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+#include <linux/syscalls.h>
+#include <linux/seq_file.h>
+
+#include <linux/mfd/da9052/da9052.h>
+#include <linux/mfd/da9052/reg.h>
+#include <linux/mfd/da9052/pdata.h>
+#include <linux/mfd/da9052/gpio.h>
+
+#define DA9052_INPUT				1
+#define DA9052_OUTPUT_OPENDRAIN		2
+#define DA9052_OUTPUT_PUSHPULL			3
+
+#define DA9052_SUPPLY_VDD_IO1			0
+
+#define DA9052_DEBOUNCING_OFF			0
+#define DA9052_DEBOUNCING_ON			1
+
+#define DA9052_OUTPUT_LOWLEVEL			0
+
+#define DA9052_ACTIVE_LOW			0
+#define DA9052_ACTIVE_HIGH			1
+
+#define DA9052_GPIO_MAX_PORTS_PER_REGISTER	8
+#define DA9052_GPIO_SHIFT_COUNT(no)		(no%8)
+#define DA9052_GPIO_MASK_UPPER_NIBBLE		0xF0
+#define DA9052_GPIO_MASK_LOWER_NIBBLE		0x0F
+#define DA9052_GPIO_NIBBLE_SHIFT		4
+
+struct da9052_gpio {
+	struct da9052 *da9052;
+	struct gpio_chip gp;
+};
+
+static inline struct da9052_gpio *to_da9052_gpio(struct gpio_chip *chip)
+{
+	return container_of(chip, struct da9052_gpio, gp);
+}
+
+static unsigned char da9052_gpio_port_odd(unsigned offset)
+{
+	return offset % 2;
+}
+
+static int da9052_gpio_get(struct gpio_chip *gc, unsigned offset)
+{
+	struct da9052_gpio *gpio = to_da9052_gpio(gc);
+	int da9052_port_direction = 0;
+	int ret;
+
+	ret = da9052_reg_read(gpio->da9052,
+			      DA9052_GPIO_0_1_REG + (offset >> 1));
+	if (ret < 0)
+		return ret;
+
+	if (da9052_gpio_port_odd(offset)) {
+		da9052_port_direction = ret & DA9052_GPIO_ODD_PORT_PIN;
+		da9052_port_direction >>= 4;
+	} else {
+		da9052_port_direction = ret & DA9052_GPIO_EVEN_PORT_PIN;
+	}
+
+	switch (da9052_port_direction) {
+	case DA9052_INPUT:
+		if (offset < DA9052_GPIO_MAX_PORTS_PER_REGISTER)
+			ret = da9052_reg_read(gpio->da9052,
+					      DA9052_STATUS_C_REG);
+		else
+			ret = da9052_reg_read(gpio->da9052,
+					      DA9052_STATUS_D_REG);
+		if (ret < 0)
+			return ret;
+		if (ret & (1 << DA9052_GPIO_SHIFT_COUNT(offset)))
+			return 1;
+		else
+			return 0;
+	case DA9052_OUTPUT_PUSHPULL:
+		if (da9052_gpio_port_odd(offset))
+			return ret & DA9052_GPIO_ODD_PORT_MODE;
+		else
+			return ret & DA9052_GPIO_EVEN_PORT_MODE;
+	default:
+		return -EINVAL;
+	}
+}
+
+static void da9052_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
+{
+	struct da9052_gpio *gpio = to_da9052_gpio(gc);
+	unsigned char register_value = 0;
+	int ret;
+
+	if (da9052_gpio_port_odd(offset)) {
+		if (value) {
+			register_value = DA9052_GPIO_ODD_PORT_MODE;
+			ret = da9052_reg_update(gpio->da9052, (offset >> 1) +
+						DA9052_GPIO_0_1_REG,
+						DA9052_GPIO_ODD_PORT_MODE,
+						register_value);
+			if (ret != 0)
+				dev_err(gpio->da9052->dev,
+					"Failed to updated gpio odd reg,%d",
+					ret);
+		}
+	} else {
+		if (value) {
+			register_value = DA9052_GPIO_EVEN_PORT_MODE;
+			ret = da9052_reg_update(gpio->da9052, (offset >> 1) +
+						DA9052_GPIO_0_1_REG,
+						DA9052_GPIO_EVEN_PORT_MODE,
+						register_value);
+			if (ret != 0)
+				dev_err(gpio->da9052->dev,
+					"Failed to updated gpio even reg,%d",
+					ret);
+		}
+	}
+}
+
+static int da9052_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
+{
+	struct da9052_gpio *gpio = to_da9052_gpio(gc);
+	unsigned char register_value;
+	int ret;
+
+	/* Format: function - 2 bits type - 1 bit mode - 1 bit */
+	register_value = DA9052_INPUT | DA9052_ACTIVE_LOW << 2 |
+			 DA9052_DEBOUNCING_ON << 3;
+
+	if (da9052_gpio_port_odd(offset))
+		ret = da9052_reg_update(gpio->da9052, (offset >> 1) +
+					DA9052_GPIO_0_1_REG,
+					DA9052_GPIO_MASK_UPPER_NIBBLE,
+					(register_value <<
+					DA9052_GPIO_NIBBLE_SHIFT));
+	else
+		ret = da9052_reg_update(gpio->da9052, (offset >> 1) +
+					DA9052_GPIO_0_1_REG,
+					DA9052_GPIO_MASK_LOWER_NIBBLE,
+					register_value);
+
+	return ret;
+}
+
+static int da9052_gpio_direction_output(struct gpio_chip *gc,
+					unsigned offset, int value)
+{
+	struct da9052_gpio *gpio = to_da9052_gpio(gc);
+	unsigned char register_value;
+	int ret;
+
+	/* Format: Function - 2 bits Type - 1 bit Mode - 1 bit */
+	register_value = DA9052_OUTPUT_PUSHPULL | DA9052_SUPPLY_VDD_IO1 << 2 |
+			 value << 3;
+
+	if (da9052_gpio_port_odd(offset))
+		ret = da9052_reg_update(gpio->da9052, (offset >> 1) +
+					DA9052_GPIO_0_1_REG,
+					DA9052_GPIO_MASK_UPPER_NIBBLE,
+					(register_value <<
+					DA9052_GPIO_NIBBLE_SHIFT));
+	else
+		ret = da9052_reg_update(gpio->da9052, (offset >> 1) +
+					DA9052_GPIO_0_1_REG,
+					DA9052_GPIO_MASK_LOWER_NIBBLE,
+					register_value);
+
+	return ret;
+}
+
+static int da9052_gpio_to_irq(struct gpio_chip *gc, u32 offset)
+{
+	struct da9052_gpio *gpio = to_da9052_gpio(gc);
+	struct da9052 *da9052 = gpio->da9052;
+
+	return da9052->irq_base + DA9052_IRQ_GPI0 + offset;
+}
+
+static struct gpio_chip reference_gp __devinitdata = {
+	.label = "da9052-gpio",
+	.owner = THIS_MODULE,
+	.get = da9052_gpio_get,
+	.set = da9052_gpio_set,
+	.direction_input = da9052_gpio_direction_input,
+	.direction_output = da9052_gpio_direction_output,
+	.to_irq = da9052_gpio_to_irq,
+	.can_sleep = 1;
+	.ngpio = 16;
+	.base = -1;
+};
+
+static int __devinit da9052_gpio_probe(struct platform_device *pdev)
+{
+	struct da9052_gpio *gpio;
+	struct da9052_pdata *pdata;
+	int ret;
+
+	gpio = kzalloc(sizeof(*gpio), GFP_KERNEL);
+	if (gpio == NULL)
+		return -ENOMEM;
+
+	gpio->da9052 = dev_get_drvdata(pdev->dev.parent);
+	pdata = gpio->da9052->dev->platform_data;
+
+	gpio->da9052 = dev_get_drvdata(pdev->dev.parent);
+	gpio->gp = reference_gp;
+	if (pdata && pdata->gpio_base)
+		gpio->gp.base = pdata->gpio_base;
+
+	ret = gpiochip_add(&gpio->gp);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
+		goto err_mem;
+	}
+
+	platform_set_drvdata(pdev, gpio);
+
+	return 0;
+
+err_mem:
+	kfree(gpio);
+	return ret;
+}
+
+static int __devexit da9052_gpio_remove(struct platform_device *pdev)
+{
+	struct da9052_gpio *gpio = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = gpiochip_remove(&gpio->gp);
+	if (ret == 0)
+		kfree(gpio);
+
+	return ret;
+}
+
+static struct platform_driver da9052_gpio_driver = {
+	.probe = da9052_gpio_probe,
+	.remove = __devexit_p(da9052_gpio_remove),
+	.driver = {
+		.name	= "da9052-gpio",
+		.owner	= THIS_MODULE,
+	},
+};
+
+static int __init da9052_gpio_init(void)
+{
+	return platform_driver_register(&da9052_gpio_driver);
+}
+module_init(da9052_gpio_init);
+
+static void __exit da9052_gpio_exit(void)
+{
+	return platform_driver_unregister(&da9052_gpio_driver);
+}
+module_exit(da9052_gpio_exit);
+
+MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
+MODULE_DESCRIPTION("DA9052 GPIO Device Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:da9052-gpio");