[ARM] S3C: Move common GPIO code from plat-s3c24xx

Move the common parts of the GPIO code into plat-s3c
for use with both the s3c24xx and s3c64xx systems.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>

3 files changed, 178 insertions, 0 deletions

diff --git a/arch/arm/plat-s3c/Makefile b/arch/arm/plat-s3c/Makefile
index b95a9c1..4d0299a 100644
--- a/arch/arm/plat-s3c/Makefile
+++ b/arch/arm/plat-s3c/Makefile
@@ -15,6 +15,7 @@ obj-y				+=  init.o
 obj-y				+= time.o
 obj-y				+= clock.o
 obj-y				+= pwm-clock.o
+obj-y				+= gpio.o
 
 # devices
 
diff --git a/arch/arm/plat-s3c/gpio.c b/arch/arm/plat-s3c/gpio.c
new file mode 100644
index 0000000..f035d45
--- /dev/null
+++ b/arch/arm/plat-s3c/gpio.c
@@ -0,0 +1,128 @@
+/* linux/arch/arm/plat-s3c/gpio.c
+ *
+ * Copyright 2008 Simtec Electronics
+ *	Ben Dooks <ben@simtec.co.uk>
+ *	http://armlinux.simtec.co.uk/
+ *
+ * S3C series GPIO core
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+
+#include <plat/gpio-core.h>
+
+/* Default routines for controlling GPIO, based on the original S3C24XX
+ * GPIO functions which deal with the case where each gpio bank of the
+ * chip is as following:
+ *
+ * base + 0x00: Control register, 2 bits per gpio
+ *	        gpio n: 2 bits starting at (2*n)
+ *		00 = input, 01 = output, others mean special-function
+ * base + 0x04: Data register, 1 bit per gpio
+ *		bit n: data bit n
+*/
+
+static int s3c_gpiolib_input(struct gpio_chip *chip, unsigned offset)
+{
+	struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
+	void __iomem *base = ourchip->base;
+	unsigned long flags;
+	unsigned long con;
+
+	local_irq_save(flags);
+
+	con = __raw_readl(base + 0x00);
+	con &= ~(3 << (offset * 2));
+
+	__raw_writel(con, base + 0x00);
+
+	local_irq_restore(flags);
+	return 0;
+}
+
+static int s3c_gpiolib_output(struct gpio_chip *chip,
+			      unsigned offset, int value)
+{
+	struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
+	void __iomem *base = ourchip->base;
+	unsigned long flags;
+	unsigned long dat;
+	unsigned long con;
+
+	local_irq_save(flags);
+
+	dat = __raw_readl(base + 0x04);
+	dat &= ~(1 << offset);
+	if (value)
+		dat |= 1 << offset;
+	__raw_writel(dat, base + 0x04);
+
+	con = __raw_readl(base + 0x00);
+	con &= ~(3 << (offset * 2));
+	con |= 1 << (offset * 2);
+
+	__raw_writel(con, base + 0x00);
+	__raw_writel(dat, base + 0x04);
+
+	local_irq_restore(flags);
+	return 0;
+}
+
+static void s3c_gpiolib_set(struct gpio_chip *chip,
+			    unsigned offset, int value)
+{
+	struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
+	void __iomem *base = ourchip->base;
+	unsigned long flags;
+	unsigned long dat;
+
+	local_irq_save(flags);
+
+	dat = __raw_readl(base + 0x04);
+	dat &= ~(1 << offset);
+	if (value)
+		dat |= 1 << offset;
+	__raw_writel(dat, base + 0x04);
+
+	local_irq_restore(flags);
+}
+
+static int s3c_gpiolib_get(struct gpio_chip *chip, unsigned offset)
+{
+	struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
+	unsigned long val;
+
+	val = __raw_readl(ourchip->base + 0x04);
+	val >>= offset;
+	val &= 1;
+
+	return val;
+}
+
+__init void s3c_gpiolib_add(struct s3c_gpio_chip *chip)
+{
+	struct gpio_chip *gc = &chip->chip;
+
+	BUG_ON(!chip->base);
+	BUG_ON(!gc->label);
+	BUG_ON(!gc->ngpio);
+
+	if (!gc->direction_input)
+		gc->direction_input = s3c_gpiolib_input;
+	if (!gc->direction_output)
+		gc->direction_output = s3c_gpiolib_output;
+	if (!gc->set)
+		gc->set = s3c_gpiolib_set;
+	if (!gc->get)
+		gc->get = s3c_gpiolib_get;
+
+	/* gpiochip_add() prints own failure message on error. */
+	gpiochip_add(gc);
+}
diff --git a/arch/arm/plat-s3c/include/plat/gpio-core.h b/arch/arm/plat-s3c/include/plat/gpio-core.h
new file mode 100644
index 0000000..3cb9105
--- /dev/null
+++ b/arch/arm/plat-s3c/include/plat/gpio-core.h
@@ -0,0 +1,49 @@
+/* linux/arch/arm/plat-s3c/include/plat/gpio-core.h
+ *
+ * Copyright 2008 Simtec Electronics
+ *	http://armlinux.simtec.co.uk/
+ *	Ben Dooks <ben@simtec.co.uk>
+ *
+ * S3C Platform - GPIO core
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+/* Define the core gpiolib support functions that the s3c platforms may
+ * need to extend or change depending on the hardware and the s3c chip
+ * selected at build or found at run time.
+ *
+ * These definitions are not intended for driver inclusion, there is
+ * nothing here that should not live outside the platform and core
+ * specific code.
+*/
+
+/**
+ * struct s3c_gpio_chip - wrapper for specific implementation of gpio
+ * @chip: The chip structure to be exported via gpiolib.
+ * @base: The base pointer to the gpio configuration registers.
+ *
+ * This wrapper provides the necessary information for the Samsung
+ * specific gpios being registered with gpiolib.
+ */
+struct s3c_gpio_chip {
+	struct gpio_chip	chip;
+	void __iomem		*base;
+};
+
+static inline struct s3c_gpio_chip *to_s3c_gpio(struct gpio_chip *gpc)
+{
+	return container_of(gpc, struct s3c_gpio_chip, chip);
+}
+
+/** s3c_gpiolib_add() - add the s3c specific version of a gpio_chip.
+ * @chip: The chip to register
+ *
+ * This is a wrapper to gpiochip_add() that takes our specific gpio chip
+ * information and makes the necessary alterations for the platform and
+ * notes the information for use with the configuration systems and any
+ * other parts of the system.
+ */
+extern void s3c_gpiolib_add(struct s3c_gpio_chip *chip);