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-rw-r--r--arch/arm/plat-samsung/gpio-samsung.c1328
1 files changed, 1328 insertions, 0 deletions
diff --git a/arch/arm/plat-samsung/gpio-samsung.c b/arch/arm/plat-samsung/gpio-samsung.c
new file mode 100644
index 000000000000..7861488f7ca0
--- /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/irqs.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_data(gc, chip);
+	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 = gpiochip_get_data(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 0;
+
+	if (soc_is_s3c24xx()) {
+		samsung_gpiolib_set_cfg(samsung_gpio_cfgs,
+				ARRAY_SIZE(samsung_gpio_cfgs));
+		s3c24xx_gpiolib_add_chips(s3c24xx_gpios,
+				ARRAY_SIZE(s3c24xx_gpios), S3C24XX_VA_GPIO);
+	} else if (soc_is_s3c64xx()) {
+		samsung_gpiolib_set_cfg(samsung_gpio_cfgs,
+				ARRAY_SIZE(samsung_gpio_cfgs));
+		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));
+	}
+
+	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