gpio: samsung: move gpio-samsung driver back to platform code

The gpio-samsung driver is special in the sense that it
interacts directly in multiple ways with the legacy platform
code for the s3c24xx and s3c64xx platforms. In contrast,
all devicetree based machines for Samsung, including the
ones on those two SoC families use a different driver.

The header files that define the interface between the platform
code and the gpio driver are not visible when building a
kernel for ARCH_MULTIPLATFORM, which prevents us from
turning on this option for s3c64xx.

To work around this, we now move the driver back into platform
code, from where it was originally moved to as part of commit
1b39d5f2cc5c28 ("gpio/samsung: gpio-samsung.c to support
Samsung GPIOs").

The long-term plan for this driver would be to remove it
entirely, after all Samsung machines have been converted
over to boot from DT, but there is currently no timeline
for when that might happen.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

3 files changed, 1333 insertions, 0 deletions

diff --git a/arch/arm/plat-samsung/Kconfig b/arch/arm/plat-samsung/Kconfig
index 57729b915003..1a1ba83e7da6 100644
--- a/arch/arm/plat-samsung/Kconfig
+++ b/arch/arm/plat-samsung/Kconfig
@@ -225,6 +225,9 @@ config S3C24XX_PWM
 	  Support for exporting the PWM timer blocks via the pwm device
 	  system
 
+config GPIO_SAMSUNG
+	def_bool y
+
 config SAMSUNG_PM_GPIO
 	bool
 	default y if GPIO_SAMSUNG && PM
diff --git a/arch/arm/plat-samsung/Makefile b/arch/arm/plat-samsung/Makefile
index 8c911760f55f..aeb19e3288b9 100644
--- a/arch/arm/plat-samsung/Makefile
+++ b/arch/arm/plat-samsung/Makefile
@@ -21,6 +21,8 @@ obj-$(CONFIG_SAMSUNG_ATAGS)	+= platformdata.o
 obj-$(CONFIG_SAMSUNG_ATAGS)	+= devs.o
 obj-$(CONFIG_SAMSUNG_ATAGS)	+= dev-uart.o
 
+obj-$(CONFIG_GPIO_SAMSUNG)     += gpio-samsung.o
+
 # PM support
 
 obj-$(CONFIG_PM_SLEEP)		+= pm-common.o
diff --git a/arch/arm/plat-samsung/gpio-samsung.c b/arch/arm/plat-samsung/gpio-samsung.c
new file mode 100644
index 000000000000..7c288ba4dc87
--- /dev/null
+++ b/arch/arm/plat-samsung/gpio-samsung.c
@@ -0,0 +1,1328 @@
+/*
+ * Copyright (c) 2009-2011 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com/
+ *
+ * Copyright 2008 Openmoko, Inc.
+ * Copyright 2008 Simtec Electronics
+ *      Ben Dooks <ben@simtec.co.uk>
+ *      http://armlinux.simtec.co.uk/
+ *
+ * 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 <linux/gpio.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/ioport.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/of_address.h>
+
+#include <asm/irq.h>
+
+#include <mach/map.h>
+#include <mach/regs-gpio.h>
+#include <mach/gpio-samsung.h>
+
+#include <plat/cpu.h>
+#include <plat/gpio-core.h>
+#include <plat/gpio-cfg.h>
+#include <plat/gpio-cfg-helpers.h>
+#include <plat/pm.h>
+
+int samsung_gpio_setpull_updown(struct samsung_gpio_chip *chip,
+				unsigned int off, samsung_gpio_pull_t pull)
+{
+	void __iomem *reg = chip->base + 0x08;
+	int shift = off * 2;
+	u32 pup;
+
+	pup = __raw_readl(reg);
+	pup &= ~(3 << shift);
+	pup |= pull << shift;
+	__raw_writel(pup, reg);
+
+	return 0;
+}
+
+samsung_gpio_pull_t samsung_gpio_getpull_updown(struct samsung_gpio_chip *chip,
+						unsigned int off)
+{
+	void __iomem *reg = chip->base + 0x08;
+	int shift = off * 2;
+	u32 pup = __raw_readl(reg);
+
+	pup >>= shift;
+	pup &= 0x3;
+
+	return (__force samsung_gpio_pull_t)pup;
+}
+
+int s3c2443_gpio_setpull(struct samsung_gpio_chip *chip,
+			 unsigned int off, samsung_gpio_pull_t pull)
+{
+	switch (pull) {
+	case S3C_GPIO_PULL_NONE:
+		pull = 0x01;
+		break;
+	case S3C_GPIO_PULL_UP:
+		pull = 0x00;
+		break;
+	case S3C_GPIO_PULL_DOWN:
+		pull = 0x02;
+		break;
+	}
+	return samsung_gpio_setpull_updown(chip, off, pull);
+}
+
+samsung_gpio_pull_t s3c2443_gpio_getpull(struct samsung_gpio_chip *chip,
+					 unsigned int off)
+{
+	samsung_gpio_pull_t pull;
+
+	pull = samsung_gpio_getpull_updown(chip, off);
+
+	switch (pull) {
+	case 0x00:
+		pull = S3C_GPIO_PULL_UP;
+		break;
+	case 0x01:
+	case 0x03:
+		pull = S3C_GPIO_PULL_NONE;
+		break;
+	case 0x02:
+		pull = S3C_GPIO_PULL_DOWN;
+		break;
+	}
+
+	return pull;
+}
+
+static int s3c24xx_gpio_setpull_1(struct samsung_gpio_chip *chip,
+				  unsigned int off, samsung_gpio_pull_t pull,
+				  samsung_gpio_pull_t updown)
+{
+	void __iomem *reg = chip->base + 0x08;
+	u32 pup = __raw_readl(reg);
+
+	if (pull == updown)
+		pup &= ~(1 << off);
+	else if (pull == S3C_GPIO_PULL_NONE)
+		pup |= (1 << off);
+	else
+		return -EINVAL;
+
+	__raw_writel(pup, reg);
+	return 0;
+}
+
+static samsung_gpio_pull_t s3c24xx_gpio_getpull_1(struct samsung_gpio_chip *chip,
+						  unsigned int off,
+						  samsung_gpio_pull_t updown)
+{
+	void __iomem *reg = chip->base + 0x08;
+	u32 pup = __raw_readl(reg);
+
+	pup &= (1 << off);
+	return pup ? S3C_GPIO_PULL_NONE : updown;
+}
+
+samsung_gpio_pull_t s3c24xx_gpio_getpull_1up(struct samsung_gpio_chip *chip,
+					     unsigned int off)
+{
+	return s3c24xx_gpio_getpull_1(chip, off, S3C_GPIO_PULL_UP);
+}
+
+int s3c24xx_gpio_setpull_1up(struct samsung_gpio_chip *chip,
+			     unsigned int off, samsung_gpio_pull_t pull)
+{
+	return s3c24xx_gpio_setpull_1(chip, off, pull, S3C_GPIO_PULL_UP);
+}
+
+samsung_gpio_pull_t s3c24xx_gpio_getpull_1down(struct samsung_gpio_chip *chip,
+					       unsigned int off)
+{
+	return s3c24xx_gpio_getpull_1(chip, off, S3C_GPIO_PULL_DOWN);
+}
+
+int s3c24xx_gpio_setpull_1down(struct samsung_gpio_chip *chip,
+			       unsigned int off, samsung_gpio_pull_t pull)
+{
+	return s3c24xx_gpio_setpull_1(chip, off, pull, S3C_GPIO_PULL_DOWN);
+}
+
+/*
+ * samsung_gpio_setcfg_2bit - Samsung 2bit style GPIO configuration.
+ * @chip: The gpio chip that is being configured.
+ * @off: The offset for the GPIO being configured.
+ * @cfg: The configuration value to set.
+ *
+ * This helper deal with the GPIO cases where the control register
+ * has two bits of configuration per gpio, which have the following
+ * functions:
+ *	00 = input
+ *	01 = output
+ *	1x = special function
+ */
+
+static int samsung_gpio_setcfg_2bit(struct samsung_gpio_chip *chip,
+				    unsigned int off, unsigned int cfg)
+{
+	void __iomem *reg = chip->base;
+	unsigned int shift = off * 2;
+	u32 con;
+
+	if (samsung_gpio_is_cfg_special(cfg)) {
+		cfg &= 0xf;
+		if (cfg > 3)
+			return -EINVAL;
+
+		cfg <<= shift;
+	}
+
+	con = __raw_readl(reg);
+	con &= ~(0x3 << shift);
+	con |= cfg;
+	__raw_writel(con, reg);
+
+	return 0;
+}
+
+/*
+ * samsung_gpio_getcfg_2bit - Samsung 2bit style GPIO configuration read.
+ * @chip: The gpio chip that is being configured.
+ * @off: The offset for the GPIO being configured.
+ *
+ * The reverse of samsung_gpio_setcfg_2bit(). Will return a value which
+ * could be directly passed back to samsung_gpio_setcfg_2bit(), from the
+ * S3C_GPIO_SPECIAL() macro.
+ */
+
+static unsigned int samsung_gpio_getcfg_2bit(struct samsung_gpio_chip *chip,
+					     unsigned int off)
+{
+	u32 con;
+
+	con = __raw_readl(chip->base);
+	con >>= off * 2;
+	con &= 3;
+
+	/* this conversion works for IN and OUT as well as special mode */
+	return S3C_GPIO_SPECIAL(con);
+}
+
+/*
+ * samsung_gpio_setcfg_4bit - Samsung 4bit single register GPIO config.
+ * @chip: The gpio chip that is being configured.
+ * @off: The offset for the GPIO being configured.
+ * @cfg: The configuration value to set.
+ *
+ * This helper deal with the GPIO cases where the control register has 4 bits
+ * of control per GPIO, generally in the form of:
+ *	0000 = Input
+ *	0001 = Output
+ *	others = Special functions (dependent on bank)
+ *
+ * Note, since the code to deal with the case where there are two control
+ * registers instead of one, we do not have a separate set of functions for
+ * each case.
+ */
+
+static int samsung_gpio_setcfg_4bit(struct samsung_gpio_chip *chip,
+				    unsigned int off, unsigned int cfg)
+{
+	void __iomem *reg = chip->base;
+	unsigned int shift = (off & 7) * 4;
+	u32 con;
+
+	if (off < 8 && chip->chip.ngpio > 8)
+		reg -= 4;
+
+	if (samsung_gpio_is_cfg_special(cfg)) {
+		cfg &= 0xf;
+		cfg <<= shift;
+	}
+
+	con = __raw_readl(reg);
+	con &= ~(0xf << shift);
+	con |= cfg;
+	__raw_writel(con, reg);
+
+	return 0;
+}
+
+/*
+ * samsung_gpio_getcfg_4bit - Samsung 4bit single register GPIO config read.
+ * @chip: The gpio chip that is being configured.
+ * @off: The offset for the GPIO being configured.
+ *
+ * The reverse of samsung_gpio_setcfg_4bit(), turning a gpio configuration
+ * register setting into a value the software can use, such as could be passed
+ * to samsung_gpio_setcfg_4bit().
+ *
+ * @sa samsung_gpio_getcfg_2bit
+ */
+
+static unsigned samsung_gpio_getcfg_4bit(struct samsung_gpio_chip *chip,
+					 unsigned int off)
+{
+	void __iomem *reg = chip->base;
+	unsigned int shift = (off & 7) * 4;
+	u32 con;
+
+	if (off < 8 && chip->chip.ngpio > 8)
+		reg -= 4;
+
+	con = __raw_readl(reg);
+	con >>= shift;
+	con &= 0xf;
+
+	/* this conversion works for IN and OUT as well as special mode */
+	return S3C_GPIO_SPECIAL(con);
+}
+
+#ifdef CONFIG_PLAT_S3C24XX
+/*
+ * s3c24xx_gpio_setcfg_abank - S3C24XX style GPIO configuration (Bank A)
+ * @chip: The gpio chip that is being configured.
+ * @off: The offset for the GPIO being configured.
+ * @cfg: The configuration value to set.
+ *
+ * This helper deal with the GPIO cases where the control register
+ * has one bit of configuration for the gpio, where setting the bit
+ * means the pin is in special function mode and unset means output.
+ */
+
+static int s3c24xx_gpio_setcfg_abank(struct samsung_gpio_chip *chip,
+				     unsigned int off, unsigned int cfg)
+{
+	void __iomem *reg = chip->base;
+	unsigned int shift = off;
+	u32 con;
+
+	if (samsung_gpio_is_cfg_special(cfg)) {
+		cfg &= 0xf;
+
+		/* Map output to 0, and SFN2 to 1 */
+		cfg -= 1;
+		if (cfg > 1)
+			return -EINVAL;
+
+		cfg <<= shift;
+	}
+
+	con = __raw_readl(reg);
+	con &= ~(0x1 << shift);
+	con |= cfg;
+	__raw_writel(con, reg);
+
+	return 0;
+}
+
+/*
+ * s3c24xx_gpio_getcfg_abank - S3C24XX style GPIO configuration read (Bank A)
+ * @chip: The gpio chip that is being configured.
+ * @off: The offset for the GPIO being configured.
+ *
+ * The reverse of s3c24xx_gpio_setcfg_abank() turning an GPIO into a usable
+ * GPIO configuration value.
+ *
+ * @sa samsung_gpio_getcfg_2bit
+ * @sa samsung_gpio_getcfg_4bit
+ */
+
+static unsigned s3c24xx_gpio_getcfg_abank(struct samsung_gpio_chip *chip,
+					  unsigned int off)
+{
+	u32 con;
+
+	con = __raw_readl(chip->base);
+	con >>= off;
+	con &= 1;
+	con++;
+
+	return S3C_GPIO_SFN(con);
+}
+#endif
+
+static void __init samsung_gpiolib_set_cfg(struct samsung_gpio_cfg *chipcfg,
+					   int nr_chips)
+{
+	for (; nr_chips > 0; nr_chips--, chipcfg++) {
+		if (!chipcfg->set_config)
+			chipcfg->set_config = samsung_gpio_setcfg_4bit;
+		if (!chipcfg->get_config)
+			chipcfg->get_config = samsung_gpio_getcfg_4bit;
+		if (!chipcfg->set_pull)
+			chipcfg->set_pull = samsung_gpio_setpull_updown;
+		if (!chipcfg->get_pull)
+			chipcfg->get_pull = samsung_gpio_getpull_updown;
+	}
+}
+
+struct samsung_gpio_cfg s3c24xx_gpiocfg_default = {
+	.set_config	= samsung_gpio_setcfg_2bit,
+	.get_config	= samsung_gpio_getcfg_2bit,
+};
+
+#ifdef CONFIG_PLAT_S3C24XX
+static struct samsung_gpio_cfg s3c24xx_gpiocfg_banka = {
+	.set_config	= s3c24xx_gpio_setcfg_abank,
+	.get_config	= s3c24xx_gpio_getcfg_abank,
+};
+#endif
+
+static struct samsung_gpio_cfg samsung_gpio_cfgs[] = {
+	[0] = {
+		.cfg_eint	= 0x0,
+	},
+	[1] = {
+		.cfg_eint	= 0x3,
+	},
+	[2] = {
+		.cfg_eint	= 0x7,
+	},
+	[3] = {
+		.cfg_eint	= 0xF,
+	},
+	[4] = {
+		.cfg_eint	= 0x0,
+		.set_config	= samsung_gpio_setcfg_2bit,
+		.get_config	= samsung_gpio_getcfg_2bit,
+	},
+	[5] = {
+		.cfg_eint	= 0x2,
+		.set_config	= samsung_gpio_setcfg_2bit,
+		.get_config	= samsung_gpio_getcfg_2bit,
+	},
+	[6] = {
+		.cfg_eint	= 0x3,
+		.set_config	= samsung_gpio_setcfg_2bit,
+		.get_config	= samsung_gpio_getcfg_2bit,
+	},
+	[7] = {
+		.set_config	= samsung_gpio_setcfg_2bit,
+		.get_config	= samsung_gpio_getcfg_2bit,
+	},
+};
+
+/*
+ * 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 samsung_gpiolib_2bit_input(struct gpio_chip *chip, unsigned offset)
+{
+	struct samsung_gpio_chip *ourchip = to_samsung_gpio(chip);
+	void __iomem *base = ourchip->base;
+	unsigned long flags;
+	unsigned long con;
+
+	samsung_gpio_lock(ourchip, flags);
+
+	con = __raw_readl(base + 0x00);
+	con &= ~(3 << (offset * 2));
+
+	__raw_writel(con, base + 0x00);
+
+	samsung_gpio_unlock(ourchip, flags);
+	return 0;
+}
+
+static int samsung_gpiolib_2bit_output(struct gpio_chip *chip,
+				       unsigned offset, int value)
+{
+	struct samsung_gpio_chip *ourchip = to_samsung_gpio(chip);
+	void __iomem *base = ourchip->base;
+	unsigned long flags;
+	unsigned long dat;
+	unsigned long con;
+
+	samsung_gpio_lock(ourchip, 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);
+
+	samsung_gpio_unlock(ourchip, flags);
+	return 0;
+}
+
+/*
+ * 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 samsung_gpiolib_get and samsung_gpiolib_set to change the
+ * state of the output.
+ */
+
+static int samsung_gpiolib_4bit_input(struct gpio_chip *chip,
+				      unsigned int offset)
+{
+	struct samsung_gpio_chip *ourchip = to_samsung_gpio(chip);
+	void __iomem *base = ourchip->base;
+	unsigned long con;
+
+	con = __raw_readl(base + GPIOCON_OFF);
+	if (ourchip->bitmap_gpio_int & BIT(offset))
+		con |= 0xf << con_4bit_shift(offset);
+	else
+		con &= ~(0xf << con_4bit_shift(offset));
+	__raw_writel(con, base + GPIOCON_OFF);
+
+	pr_debug("%s: %p: CON now %08lx\n", __func__, base, con);
+
+	return 0;
+}
+
+static int samsung_gpiolib_4bit_output(struct gpio_chip *chip,
+				       unsigned int offset, int value)
+{
+	struct samsung_gpio_chip *ourchip = to_samsung_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);
+
+	pr_debug("%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 samsung_gpiolib_get and samsung_gpiolib_set
+ * routines we store the 'base + 0x4' address so that these routines see
+ * the data register at ourchip->base + 0x04.
+ */
+
+static int samsung_gpiolib_4bit2_input(struct gpio_chip *chip,
+				       unsigned int offset)
+{
+	struct samsung_gpio_chip *ourchip = to_samsung_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);
+
+	pr_debug("%s: %p: CON %08lx\n", __func__, base, con);
+
+	return 0;
+}
+
+static int samsung_gpiolib_4bit2_output(struct gpio_chip *chip,
+					unsigned int offset, int value)
+{
+	struct samsung_gpio_chip *ourchip = to_samsung_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);
+
+	pr_debug("%s: %p: CON %08lx, DAT %08lx\n", __func__, base, con, dat);
+
+	return 0;
+}
+
+#ifdef CONFIG_PLAT_S3C24XX
+/* The next set of routines are for the case of s3c24xx bank a */
+
+static int s3c24xx_gpiolib_banka_input(struct gpio_chip *chip, unsigned offset)
+{
+	return -EINVAL;
+}
+
+static int s3c24xx_gpiolib_banka_output(struct gpio_chip *chip,
+					unsigned offset, int value)
+{
+	struct samsung_gpio_chip *ourchip = to_samsung_gpio(chip);
+	void __iomem *base = ourchip->base;
+	unsigned long flags;
+	unsigned long dat;
+	unsigned long con;
+
+	local_irq_save(flags);
+
+	con = __raw_readl(base + 0x00);
+	dat = __raw_readl(base + 0x04);
+
+	dat &= ~(1 << offset);
+	if (value)
+		dat |= 1 << offset;
+
+	__raw_writel(dat, base + 0x04);
+
+	con &= ~(1 << offset);
+
+	__raw_writel(con, base + 0x00);
+	__raw_writel(dat, base + 0x04);
+
+	local_irq_restore(flags);
+	return 0;
+}
+#endif
+
+static void samsung_gpiolib_set(struct gpio_chip *chip,
+				unsigned offset, int value)
+{
+	struct samsung_gpio_chip *ourchip = to_samsung_gpio(chip);
+	void __iomem *base = ourchip->base;
+	unsigned long flags;
+	unsigned long dat;
+
+	samsung_gpio_lock(ourchip, flags);
+
+	dat = __raw_readl(base + 0x04);
+	dat &= ~(1 << offset);
+	if (value)
+		dat |= 1 << offset;
+	__raw_writel(dat, base + 0x04);
+
+	samsung_gpio_unlock(ourchip, flags);
+}
+
+static int samsung_gpiolib_get(struct gpio_chip *chip, unsigned offset)
+{
+	struct samsung_gpio_chip *ourchip = to_samsung_gpio(chip);
+	unsigned long val;
+
+	val = __raw_readl(ourchip->base + 0x04);
+	val >>= offset;
+	val &= 1;
+
+	return val;
+}
+
+/*
+ * CONFIG_S3C_GPIO_TRACK enables the tracking of the s3c specific gpios
+ * for use with the configuration calls, and other parts of the s3c gpiolib
+ * support code.
+ *
+ * Not all s3c support code will need this, as some configurations of cpu
+ * may only support one or two different configuration options and have an
+ * easy gpio to samsung_gpio_chip mapping function. If this is the case, then
+ * the machine support file should provide its own samsung_gpiolib_getchip()
+ * and any other necessary functions.
+ */
+
+#ifdef CONFIG_S3C_GPIO_TRACK
+struct samsung_gpio_chip *s3c_gpios[S3C_GPIO_END];
+
+static __init void s3c_gpiolib_track(struct samsung_gpio_chip *chip)
+{
+	unsigned int gpn;
+	int i;
+
+	gpn = chip->chip.base;
+	for (i = 0; i < chip->chip.ngpio; i++, gpn++) {
+		BUG_ON(gpn >= ARRAY_SIZE(s3c_gpios));
+		s3c_gpios[gpn] = chip;
+	}
+}
+#endif /* CONFIG_S3C_GPIO_TRACK */
+
+/*
+ * samsung_gpiolib_add() - add the Samsung 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.
+ */
+
+static void __init samsung_gpiolib_add(struct samsung_gpio_chip *chip)
+{
+	struct gpio_chip *gc = &chip->chip;
+	int ret;
+
+	BUG_ON(!chip->base);
+	BUG_ON(!gc->label);
+	BUG_ON(!gc->ngpio);
+
+	spin_lock_init(&chip->lock);
+
+	if (!gc->direction_input)
+		gc->direction_input = samsung_gpiolib_2bit_input;
+	if (!gc->direction_output)
+		gc->direction_output = samsung_gpiolib_2bit_output;
+	if (!gc->set)
+		gc->set = samsung_gpiolib_set;
+	if (!gc->get)
+		gc->get = samsung_gpiolib_get;
+
+#ifdef CONFIG_PM
+	if (chip->pm != NULL) {
+		if (!chip->pm->save || !chip->pm->resume)
+			pr_err("gpio: %s has missing PM functions\n",
+			       gc->label);
+	} else
+		pr_err("gpio: %s has no PM function\n", gc->label);
+#endif
+
+	/* gpiochip_add() prints own failure message on error. */
+	ret = gpiochip_add(gc);
+	if (ret >= 0)
+		s3c_gpiolib_track(chip);
+}
+
+static void __init s3c24xx_gpiolib_add_chips(struct samsung_gpio_chip *chip,
+					     int nr_chips, void __iomem *base)
+{
+	int i;
+	struct gpio_chip *gc = &chip->chip;
+
+	for (i = 0 ; i < nr_chips; i++, chip++) {
+		/* skip banks not present on SoC */
+		if (chip->chip.base >= S3C_GPIO_END)
+			continue;
+
+		if (!chip->config)
+			chip->config = &s3c24xx_gpiocfg_default;
+		if (!chip->pm)
+			chip->pm = __gpio_pm(&samsung_gpio_pm_2bit);
+		if ((base != NULL) && (chip->base == NULL))
+			chip->base = base + ((i) * 0x10);
+
+		if (!gc->direction_input)
+			gc->direction_input = samsung_gpiolib_2bit_input;
+		if (!gc->direction_output)
+			gc->direction_output = samsung_gpiolib_2bit_output;
+
+		samsung_gpiolib_add(chip);
+	}
+}
+
+static void __init samsung_gpiolib_add_2bit_chips(struct samsung_gpio_chip *chip,
+						  int nr_chips, void __iomem *base,
+						  unsigned int offset)
+{
+	int i;
+
+	for (i = 0 ; i < nr_chips; i++, chip++) {
+		chip->chip.direction_input = samsung_gpiolib_2bit_input;
+		chip->chip.direction_output = samsung_gpiolib_2bit_output;
+
+		if (!chip->config)
+			chip->config = &samsung_gpio_cfgs[7];
+		if (!chip->pm)
+			chip->pm = __gpio_pm(&samsung_gpio_pm_2bit);
+		if ((base != NULL) && (chip->base == NULL))
+			chip->base = base + ((i) * offset);
+
+		samsung_gpiolib_add(chip);
+	}
+}
+
+/*
+ * samsung_gpiolib_add_4bit_chips - 4bit single register GPIO config.
+ * @chip: The gpio chip that is being configured.
+ * @nr_chips: The no of chips (gpio ports) for the GPIO being configured.
+ *
+ * This helper deal with the GPIO cases where the control register has 4 bits
+ * of control per GPIO, generally in the form of:
+ * 0000 = Input
+ * 0001 = Output
+ * others = Special functions (dependent on bank)
+ *
+ * Note, since the code to deal with the case where there are two control
+ * registers instead of one, we do not have a separate set of function
+ * (samsung_gpiolib_add_4bit2_chips)for each case.
+ */
+
+static void __init samsung_gpiolib_add_4bit_chips(struct samsung_gpio_chip *chip,
+						  int nr_chips, void __iomem *base)
+{
+	int i;
+
+	for (i = 0 ; i < nr_chips; i++, chip++) {
+		chip->chip.direction_input = samsung_gpiolib_4bit_input;
+		chip->chip.direction_output = samsung_gpiolib_4bit_output;
+
+		if (!chip->config)
+			chip->config = &samsung_gpio_cfgs[2];
+		if (!chip->pm)
+			chip->pm = __gpio_pm(&samsung_gpio_pm_4bit);
+		if ((base != NULL) && (chip->base == NULL))
+			chip->base = base + ((i) * 0x20);
+
+		chip->bitmap_gpio_int = 0;
+
+		samsung_gpiolib_add(chip);
+	}
+}
+
+static void __init samsung_gpiolib_add_4bit2_chips(struct samsung_gpio_chip *chip,
+						   int nr_chips)
+{
+	for (; nr_chips > 0; nr_chips--, chip++) {
+		chip->chip.direction_input = samsung_gpiolib_4bit2_input;
+		chip->chip.direction_output = samsung_gpiolib_4bit2_output;
+
+		if (!chip->config)
+			chip->config = &samsung_gpio_cfgs[2];
+		if (!chip->pm)
+			chip->pm = __gpio_pm(&samsung_gpio_pm_4bit);
+
+		samsung_gpiolib_add(chip);
+	}
+}
+
+int samsung_gpiolib_to_irq(struct gpio_chip *chip, unsigned int offset)
+{
+	struct samsung_gpio_chip *samsung_chip = container_of(chip, struct samsung_gpio_chip, chip);
+
+	return samsung_chip->irq_base + offset;
+}
+
+#ifdef CONFIG_PLAT_S3C24XX
+static int s3c24xx_gpiolib_fbank_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+	if (offset < 4) {
+		if (soc_is_s3c2412())
+			return IRQ_EINT0_2412 + offset;
+		else
+			return IRQ_EINT0 + offset;
+	}
+
+	if (offset < 8)
+		return IRQ_EINT4 + offset - 4;
+
+	return -EINVAL;
+}
+#endif
+
+#ifdef CONFIG_ARCH_S3C64XX
+static int s3c64xx_gpiolib_mbank_to_irq(struct gpio_chip *chip, unsigned pin)
+{
+	return pin < 5 ? IRQ_EINT(23) + pin : -ENXIO;
+}
+
+static int s3c64xx_gpiolib_lbank_to_irq(struct gpio_chip *chip, unsigned pin)
+{
+	return pin >= 8 ? IRQ_EINT(16) + pin - 8 : -ENXIO;
+}
+#endif
+
+struct samsung_gpio_chip s3c24xx_gpios[] = {
+#ifdef CONFIG_PLAT_S3C24XX
+	{
+		.config	= &s3c24xx_gpiocfg_banka,
+		.chip	= {
+			.base			= S3C2410_GPA(0),
+			.owner			= THIS_MODULE,
+			.label			= "GPIOA",
+			.ngpio			= 27,
+			.direction_input	= s3c24xx_gpiolib_banka_input,
+			.direction_output	= s3c24xx_gpiolib_banka_output,
+		},
+	}, {
+		.chip	= {
+			.base	= S3C2410_GPB(0),
+			.owner	= THIS_MODULE,
+			.label	= "GPIOB",
+			.ngpio	= 11,
+		},
+	}, {
+		.chip	= {
+			.base	= S3C2410_GPC(0),
+			.owner	= THIS_MODULE,
+			.label	= "GPIOC",
+			.ngpio	= 16,
+		},
+	}, {
+		.chip	= {
+			.base	= S3C2410_GPD(0),
+			.owner	= THIS_MODULE,
+			.label	= "GPIOD",
+			.ngpio	= 16,
+		},
+	}, {
+		.chip	= {
+			.base	= S3C2410_GPE(0),
+			.label	= "GPIOE",
+			.owner	= THIS_MODULE,
+			.ngpio	= 16,
+		},
+	}, {
+		.chip	= {
+			.base	= S3C2410_GPF(0),
+			.owner	= THIS_MODULE,
+			.label	= "GPIOF",
+			.ngpio	= 8,
+			.to_irq	= s3c24xx_gpiolib_fbank_to_irq,
+		},
+	}, {
+		.irq_base = IRQ_EINT8,
+		.chip	= {
+			.base	= S3C2410_GPG(0),
+			.owner	= THIS_MODULE,
+			.label	= "GPIOG",
+			.ngpio	= 16,
+			.to_irq	= samsung_gpiolib_to_irq,
+		},
+	}, {
+		.chip	= {
+			.base	= S3C2410_GPH(0),
+			.owner	= THIS_MODULE,
+			.label	= "GPIOH",
+			.ngpio	= 15,
+		},
+	},
+		/* GPIOS for the S3C2443 and later devices. */
+	{
+		.base	= S3C2440_GPJCON,
+		.chip	= {
+			.base	= S3C2410_GPJ(0),
+			.owner	= THIS_MODULE,
+			.label	= "GPIOJ",
+			.ngpio	= 16,
+		},
+	}, {
+		.base	= S3C2443_GPKCON,
+		.chip	= {
+			.base	= S3C2410_GPK(0),
+			.owner	= THIS_MODULE,
+			.label	= "GPIOK",
+			.ngpio	= 16,
+		},
+	}, {
+		.base	= S3C2443_GPLCON,
+		.chip	= {
+			.base	= S3C2410_GPL(0),
+			.owner	= THIS_MODULE,
+			.label	= "GPIOL",
+			.ngpio	= 15,
+		},
+	}, {
+		.base	= S3C2443_GPMCON,
+		.chip	= {
+			.base	= S3C2410_GPM(0),
+			.owner	= THIS_MODULE,
+			.label	= "GPIOM",
+			.ngpio	= 2,
+		},
+	},
+#endif
+};
+
+/*
+ * GPIO bank summary:
+ *
+ * Bank	GPIOs	Style	SlpCon	ExtInt Group
+ * A	8	4Bit	Yes	1
+ * B	7	4Bit	Yes	1
+ * C	8	4Bit	Yes	2
+ * D	5	4Bit	Yes	3
+ * E	5	4Bit	Yes	None
+ * F	16	2Bit	Yes	4 [1]
+ * G	7	4Bit	Yes	5
+ * H	10	4Bit[2]	Yes	6
+ * I	16	2Bit	Yes	None
+ * J	12	2Bit	Yes	None
+ * K	16	4Bit[2]	No	None
+ * L	15	4Bit[2] No	None
+ * M	6	4Bit	No	IRQ_EINT
+ * N	16	2Bit	No	IRQ_EINT
+ * O	16	2Bit	Yes	7
+ * P	15	2Bit	Yes	8
+ * Q	9	2Bit	Yes	9
+ *
+ * [1] BANKF pins 14,15 do not form part of the external interrupt sources
+ * [2] BANK has two control registers, GPxCON0 and GPxCON1
+ */
+
+static struct samsung_gpio_chip s3c64xx_gpios_4bit[] = {
+#ifdef CONFIG_ARCH_S3C64XX
+	{
+		.chip	= {
+			.base	= S3C64XX_GPA(0),
+			.ngpio	= S3C64XX_GPIO_A_NR,
+			.label	= "GPA",
+		},
+	}, {
+		.chip	= {
+			.base	= S3C64XX_GPB(0),
+			.ngpio	= S3C64XX_GPIO_B_NR,
+			.label	= "GPB",
+		},
+	}, {
+		.chip	= {
+			.base	= S3C64XX_GPC(0),
+			.ngpio	= S3C64XX_GPIO_C_NR,
+			.label	= "GPC",
+		},
+	}, {
+		.chip	= {
+			.base	= S3C64XX_GPD(0),
+			.ngpio	= S3C64XX_GPIO_D_NR,
+			.label	= "GPD",
+		},
+	}, {
+		.config	= &samsung_gpio_cfgs[0],
+		.chip	= {
+			.base	= S3C64XX_GPE(0),
+			.ngpio	= S3C64XX_GPIO_E_NR,
+			.label	= "GPE",
+		},
+	}, {
+		.base	= S3C64XX_GPG_BASE,
+		.chip	= {
+			.base	= S3C64XX_GPG(0),
+			.ngpio	= S3C64XX_GPIO_G_NR,
+			.label	= "GPG",
+		},
+	}, {
+		.base	= S3C64XX_GPM_BASE,
+		.config	= &samsung_gpio_cfgs[1],
+		.chip	= {
+			.base	= S3C64XX_GPM(0),
+			.ngpio	= S3C64XX_GPIO_M_NR,
+			.label	= "GPM",
+			.to_irq = s3c64xx_gpiolib_mbank_to_irq,
+		},
+	},
+#endif
+};
+
+static struct samsung_gpio_chip s3c64xx_gpios_4bit2[] = {
+#ifdef CONFIG_ARCH_S3C64XX
+	{
+		.base	= S3C64XX_GPH_BASE + 0x4,
+		.chip	= {
+			.base	= S3C64XX_GPH(0),
+			.ngpio	= S3C64XX_GPIO_H_NR,
+			.label	= "GPH",
+		},
+	}, {
+		.base	= S3C64XX_GPK_BASE + 0x4,
+		.config	= &samsung_gpio_cfgs[0],
+		.chip	= {
+			.base	= S3C64XX_GPK(0),
+			.ngpio	= S3C64XX_GPIO_K_NR,
+			.label	= "GPK",
+		},
+	}, {
+		.base	= S3C64XX_GPL_BASE + 0x4,
+		.config	= &samsung_gpio_cfgs[1],
+		.chip	= {
+			.base	= S3C64XX_GPL(0),
+			.ngpio	= S3C64XX_GPIO_L_NR,
+			.label	= "GPL",
+			.to_irq = s3c64xx_gpiolib_lbank_to_irq,
+		},
+	},
+#endif
+};
+
+static struct samsung_gpio_chip s3c64xx_gpios_2bit[] = {
+#ifdef CONFIG_ARCH_S3C64XX
+	{
+		.base	= S3C64XX_GPF_BASE,
+		.config	= &samsung_gpio_cfgs[6],
+		.chip	= {
+			.base	= S3C64XX_GPF(0),
+			.ngpio	= S3C64XX_GPIO_F_NR,
+			.label	= "GPF",
+		},
+	}, {
+		.config	= &samsung_gpio_cfgs[7],
+		.chip	= {
+			.base	= S3C64XX_GPI(0),
+			.ngpio	= S3C64XX_GPIO_I_NR,
+			.label	= "GPI",
+		},
+	}, {
+		.config	= &samsung_gpio_cfgs[7],
+		.chip	= {
+			.base	= S3C64XX_GPJ(0),
+			.ngpio	= S3C64XX_GPIO_J_NR,
+			.label	= "GPJ",
+		},
+	}, {
+		.config	= &samsung_gpio_cfgs[6],
+		.chip	= {
+			.base	= S3C64XX_GPO(0),
+			.ngpio	= S3C64XX_GPIO_O_NR,
+			.label	= "GPO",
+		},
+	}, {
+		.config	= &samsung_gpio_cfgs[6],
+		.chip	= {
+			.base	= S3C64XX_GPP(0),
+			.ngpio	= S3C64XX_GPIO_P_NR,
+			.label	= "GPP",
+		},
+	}, {
+		.config	= &samsung_gpio_cfgs[6],
+		.chip	= {
+			.base	= S3C64XX_GPQ(0),
+			.ngpio	= S3C64XX_GPIO_Q_NR,
+			.label	= "GPQ",
+		},
+	}, {
+		.base	= S3C64XX_GPN_BASE,
+		.irq_base = IRQ_EINT(0),
+		.config	= &samsung_gpio_cfgs[5],
+		.chip	= {
+			.base	= S3C64XX_GPN(0),
+			.ngpio	= S3C64XX_GPIO_N_NR,
+			.label	= "GPN",
+			.to_irq = samsung_gpiolib_to_irq,
+		},
+	},
+#endif
+};
+
+/* TODO: cleanup soc_is_* */
+static __init int samsung_gpiolib_init(void)
+{
+	/*
+	 * Currently there are two drivers that can provide GPIO support for
+	 * Samsung SoCs. For device tree enabled platforms, the new
+	 * pinctrl-samsung driver is used, providing both GPIO and pin control
+	 * interfaces. For legacy (non-DT) platforms this driver is used.
+	 */
+	if (of_have_populated_dt())
+		return -ENODEV;
+
+	samsung_gpiolib_set_cfg(samsung_gpio_cfgs, ARRAY_SIZE(samsung_gpio_cfgs));
+
+	if (soc_is_s3c24xx()) {
+		s3c24xx_gpiolib_add_chips(s3c24xx_gpios,
+				ARRAY_SIZE(s3c24xx_gpios), S3C24XX_VA_GPIO);
+	} else if (soc_is_s3c64xx()) {
+		samsung_gpiolib_add_2bit_chips(s3c64xx_gpios_2bit,
+				ARRAY_SIZE(s3c64xx_gpios_2bit),
+				S3C64XX_VA_GPIO + 0xE0, 0x20);
+		samsung_gpiolib_add_4bit_chips(s3c64xx_gpios_4bit,
+				ARRAY_SIZE(s3c64xx_gpios_4bit),
+				S3C64XX_VA_GPIO);
+		samsung_gpiolib_add_4bit2_chips(s3c64xx_gpios_4bit2,
+				ARRAY_SIZE(s3c64xx_gpios_4bit2));
+	} else {
+		WARN(1, "Unknown SoC in gpio-samsung, no GPIOs added\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+core_initcall(samsung_gpiolib_init);
+
+int s3c_gpio_cfgpin(unsigned int pin, unsigned int config)
+{
+	struct samsung_gpio_chip *chip = samsung_gpiolib_getchip(pin);
+	unsigned long flags;
+	int offset;
+	int ret;
+
+	if (!chip)
+		return -EINVAL;
+
+	offset = pin - chip->chip.base;
+
+	samsung_gpio_lock(chip, flags);
+	ret = samsung_gpio_do_setcfg(chip, offset, config);
+	samsung_gpio_unlock(chip, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL(s3c_gpio_cfgpin);
+
+int s3c_gpio_cfgpin_range(unsigned int start, unsigned int nr,
+			  unsigned int cfg)
+{
+	int ret;
+
+	for (; nr > 0; nr--, start++) {
+		ret = s3c_gpio_cfgpin(start, cfg);
+		if (ret != 0)
+			return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(s3c_gpio_cfgpin_range);
+
+int s3c_gpio_cfgall_range(unsigned int start, unsigned int nr,
+			  unsigned int cfg, samsung_gpio_pull_t pull)
+{
+	int ret;
+
+	for (; nr > 0; nr--, start++) {
+		s3c_gpio_setpull(start, pull);
+		ret = s3c_gpio_cfgpin(start, cfg);
+		if (ret != 0)
+			return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(s3c_gpio_cfgall_range);
+
+unsigned s3c_gpio_getcfg(unsigned int pin)
+{
+	struct samsung_gpio_chip *chip = samsung_gpiolib_getchip(pin);
+	unsigned long flags;
+	unsigned ret = 0;
+	int offset;
+
+	if (chip) {
+		offset = pin - chip->chip.base;
+
+		samsung_gpio_lock(chip, flags);
+		ret = samsung_gpio_do_getcfg(chip, offset);
+		samsung_gpio_unlock(chip, flags);
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL(s3c_gpio_getcfg);
+
+int s3c_gpio_setpull(unsigned int pin, samsung_gpio_pull_t pull)
+{
+	struct samsung_gpio_chip *chip = samsung_gpiolib_getchip(pin);
+	unsigned long flags;
+	int offset, ret;
+
+	if (!chip)
+		return -EINVAL;
+
+	offset = pin - chip->chip.base;
+
+	samsung_gpio_lock(chip, flags);
+	ret = samsung_gpio_do_setpull(chip, offset, pull);
+	samsung_gpio_unlock(chip, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL(s3c_gpio_setpull);
+
+samsung_gpio_pull_t s3c_gpio_getpull(unsigned int pin)
+{
+	struct samsung_gpio_chip *chip = samsung_gpiolib_getchip(pin);
+	unsigned long flags;
+	int offset;
+	u32 pup = 0;
+
+	if (chip) {
+		offset = pin - chip->chip.base;
+
+		samsung_gpio_lock(chip, flags);
+		pup = samsung_gpio_do_getpull(chip, offset);
+		samsung_gpio_unlock(chip, flags);
+	}
+
+	return (__force samsung_gpio_pull_t)pup;
+}
+EXPORT_SYMBOL(s3c_gpio_getpull);
+
+#ifdef CONFIG_PLAT_S3C24XX
+unsigned int s3c2410_modify_misccr(unsigned int clear, unsigned int change)
+{
+	unsigned long flags;
+	unsigned long misccr;
+
+	local_irq_save(flags);
+	misccr = __raw_readl(S3C24XX_MISCCR);
+	misccr &= ~clear;
+	misccr ^= change;
+	__raw_writel(misccr, S3C24XX_MISCCR);
+	local_irq_restore(flags);
+
+	return misccr;
+}
+EXPORT_SYMBOL(s3c2410_modify_misccr);
+#endif