ARM: SAMSUNG: Move GPIO common functions to plat-samsung

This patch moves GPIO common functions (from plat-s3c64xx) into plat-samsung.
and adds the config option to build the plat-samsung/gpiolib for Samsung SoCs.

Signed-off-by: Adityapratap Sharma <aditya.ps@samsung.com>
Signed-off-by: Atul Dahiya <atul.dahiya@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>

3 files changed, 205 insertions, 0 deletions

diff --git a/arch/arm/plat-samsung/Kconfig b/arch/arm/plat-samsung/Kconfig
index e6c122967355..6484b5bf82c3 100644
--- a/arch/arm/plat-samsung/Kconfig
+++ b/arch/arm/plat-samsung/Kconfig
@@ -33,6 +33,13 @@ config SAMSUNG_IRQ_UART
 
 # options for gpio configuration support
 
+config SAMSUNG_GPIOLIB_4BIT
+	bool
+	help
+	  GPIOlib file contains the 4 bit modification functions for gpio
+	  configuration. GPIOlib shall be compiled only for S3C64XX and S5P
+	  series of processors.
+
 config S3C_GPIO_CFG_S3C24XX
 	bool
 	help
diff --git a/arch/arm/plat-samsung/Makefile b/arch/arm/plat-samsung/Makefile
index ceac416d80b8..1fc8d471c6ee 100644
--- a/arch/arm/plat-samsung/Makefile
+++ b/arch/arm/plat-samsung/Makefile
@@ -15,6 +15,7 @@ obj-y				+= clock.o
 obj-y				+= pwm-clock.o
 obj-y				+= gpio-config.o
 
+obj-$(CONFIG_SAMSUNG_GPIOLIB_4BIT)	+= gpiolib.o
 obj-$(CONFIG_SAMSUNG_CLKSRC)	+= clock-clksrc.o
 
 obj-$(CONFIG_SAMSUNG_IRQ_UART)	+= irq-uart.o
diff --git a/arch/arm/plat-samsung/gpiolib.c b/arch/arm/plat-samsung/gpiolib.c
new file mode 100644
index 000000000000..3419b67f4221
--- /dev/null
+++ b/arch/arm/plat-samsung/gpiolib.c
@@ -0,0 +1,197 @@
+/* arch/arm/plat-samsung/gpiolib.c
+ *
+ * Copyright 2008 Openmoko, Inc.
+ * Copyright 2008 Simtec Electronics
+ *      Ben Dooks <ben@simtec.co.uk>
+ *      http://armlinux.simtec.co.uk/
+ *
+ * Copyright (c) 2009 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com/
+ *
+ * SAMSUNG - GPIOlib support
+ *
+ * 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/irq.h>
+#include <linux/io.h>
+#include <mach/gpio.h>
+#include <plat/gpio-core.h>
+#include <plat/gpio-cfg.h>
+#include <plat/gpio-cfg-helpers.h>
+
+#ifndef DEBUG_GPIO
+#define gpio_dbg(x...) do { } while (0)
+#else
+#define gpio_dbg(x...) printk(KERN_DEBUG x)
+#endif
+
+/* The samsung_gpiolib_4bit routines are to control the gpio banks where
+ * the gpio configuration register (GPxCON) has 4 bits per GPIO, as the
+ * following example:
+ *
+ * base + 0x00: Control register, 4 bits per gpio
+ *		gpio n: 4 bits starting at (4*n)
+ *		0000 = input, 0001 = output, others mean special-function
+ * base + 0x04: Data register, 1 bit per gpio
+ *		bit n: data bit n
+ *
+ * Note, since the data register is one bit per gpio and is at base + 0x4
+ * we can use s3c_gpiolib_get and s3c_gpiolib_set to change the state of
+ * the output.
+*/
+
+int samsung_gpiolib_4bit_input(struct gpio_chip *chip, unsigned int offset)
+{
+	struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
+	void __iomem *base = ourchip->base;
+	unsigned long con;
+
+	con = __raw_readl(base + GPIOCON_OFF);
+	con &= ~(0xf << con_4bit_shift(offset));
+	__raw_writel(con, base + GPIOCON_OFF);
+
+	gpio_dbg("%s: %p: CON now %08lx\n", __func__, base, con);
+
+	return 0;
+}
+
+int samsung_gpiolib_4bit_output(struct gpio_chip *chip,
+				unsigned int offset, int value)
+{
+	struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
+	void __iomem *base = ourchip->base;
+	unsigned long con;
+	unsigned long dat;
+
+	con = __raw_readl(base + GPIOCON_OFF);
+	con &= ~(0xf << con_4bit_shift(offset));
+	con |= 0x1 << con_4bit_shift(offset);
+
+	dat = __raw_readl(base + GPIODAT_OFF);
+
+	if (value)
+		dat |= 1 << offset;
+	else
+		dat &= ~(1 << offset);
+
+	__raw_writel(dat, base + GPIODAT_OFF);
+	__raw_writel(con, base + GPIOCON_OFF);
+	__raw_writel(dat, base + GPIODAT_OFF);
+
+	gpio_dbg("%s: %p: CON %08lx, DAT %08lx\n", __func__, base, con, dat);
+
+	return 0;
+}
+
+/* The next set of routines are for the case where the GPIO configuration
+ * registers are 4 bits per GPIO but there is more than one register (the
+ * bank has more than 8 GPIOs.
+ *
+ * This case is the similar to the 4 bit case, but the registers are as
+ * follows:
+ *
+ * base + 0x00: Control register, 4 bits per gpio (lower 8 GPIOs)
+ *		gpio n: 4 bits starting at (4*n)
+ *		0000 = input, 0001 = output, others mean special-function
+ * base + 0x04: Control register, 4 bits per gpio (up to 8 additions GPIOs)
+ *		gpio n: 4 bits starting at (4*n)
+ *		0000 = input, 0001 = output, others mean special-function
+ * base + 0x08: Data register, 1 bit per gpio
+ *		bit n: data bit n
+ *
+ * To allow us to use the s3c_gpiolib_get and s3c_gpiolib_set routines we
+ * store the 'base + 0x4' address so that these routines see the data
+ * register at ourchip->base + 0x04.
+*/
+
+int samsung_gpiolib_4bit2_input(struct gpio_chip *chip, unsigned int offset)
+{
+	struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
+	void __iomem *base = ourchip->base;
+	void __iomem *regcon = base;
+	unsigned long con;
+
+	if (offset > 7)
+		offset -= 8;
+	else
+		regcon -= 4;
+
+	con = __raw_readl(regcon);
+	con &= ~(0xf << con_4bit_shift(offset));
+	__raw_writel(con, regcon);
+
+	gpio_dbg("%s: %p: CON %08lx\n", __func__, base, con);
+
+	return 0;
+}
+
+int samsung_gpiolib_4bit2_output(struct gpio_chip *chip,
+				 unsigned int offset, int value)
+{
+	struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
+	void __iomem *base = ourchip->base;
+	void __iomem *regcon = base;
+	unsigned long con;
+	unsigned long dat;
+	unsigned con_offset = offset;
+
+	if (con_offset > 7)
+		con_offset -= 8;
+	else
+		regcon -= 4;
+
+	con = __raw_readl(regcon);
+	con &= ~(0xf << con_4bit_shift(con_offset));
+	con |= 0x1 << con_4bit_shift(con_offset);
+
+	dat = __raw_readl(base + GPIODAT_OFF);
+
+	if (value)
+		dat |= 1 << offset;
+	else
+		dat &= ~(1 << offset);
+
+	__raw_writel(dat, base + GPIODAT_OFF);
+	__raw_writel(con, regcon);
+	__raw_writel(dat, base + GPIODAT_OFF);
+
+	gpio_dbg("%s: %p: CON %08lx, DAT %08lx\n", __func__, base, con, dat);
+
+	return 0;
+}
+
+void __init samsung_gpiolib_add_4bit(struct s3c_gpio_chip *chip)
+{
+	chip->chip.direction_input = samsung_gpiolib_4bit_input;
+	chip->chip.direction_output = samsung_gpiolib_4bit_output;
+	chip->pm = __gpio_pm(&s3c_gpio_pm_4bit);
+}
+
+void __init samsung_gpiolib_add_4bit2(struct s3c_gpio_chip *chip)
+{
+	chip->chip.direction_input = samsung_gpiolib_4bit2_input;
+	chip->chip.direction_output = samsung_gpiolib_4bit2_output;
+	chip->pm = __gpio_pm(&s3c_gpio_pm_4bit);
+}
+
+void __init samsung_gpiolib_add_4bit_chips(struct s3c_gpio_chip *chip,
+					   int nr_chips)
+{
+	for (; nr_chips > 0; nr_chips--, chip++) {
+		samsung_gpiolib_add_4bit(chip);
+		s3c_gpiolib_add(chip);
+	}
+}
+
+void __init samsung_gpiolib_add_4bit2_chips(struct s3c_gpio_chip *chip,
+					    int nr_chips)
+{
+	for (; nr_chips > 0; nr_chips--, chip++) {
+		samsung_gpiolib_add_4bit2(chip);
+		s3c_gpiolib_add(chip);
+	}
+}