[ARM] S3C: Add new GPIO configuration calls

Add new GPIO configuration calls that mesh with the
new gpiolib support.

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

6 files changed, 484 insertions, 2 deletions

diff --git a/arch/arm/plat-s3c/Kconfig b/arch/arm/plat-s3c/Kconfig
index 77fc38f51874..45e62cba595c 100644
--- a/arch/arm/plat-s3c/Kconfig
+++ b/arch/arm/plat-s3c/Kconfig
@@ -120,6 +120,33 @@ config S3C_GPIO_TRACK
           Internal configuration option to enable the s3c specific gpio
           chip tracking if the platform requires it.
 
+config S3C_GPIO_PULL_UPDOWN
+        bool
+        help
+          Internal configuration to enable the correct GPIO pull helper
+
+config S3C_GPIO_PULL_DOWN
+        bool
+        help
+          Internal configuration to enable the correct GPIO pull helper
+
+config S3C_GPIO_PULL_UP
+        bool
+        help
+          Internal configuration to enable the correct GPIO pull helper
+
+config S3C_GPIO_CFG_S3C24XX
+        bool
+        help
+          Internal configuration to enable S3C24XX style GPIO configuration
+          functions.
+
+config S3C_GPIO_CFG_S3C64XX
+        bool
+        help
+          Internal configuration to enable S3C64XX style GPIO configuration
+          functions.
+
 # device definitions to compile in
 
 config S3C_DEV_HSMMC
diff --git a/arch/arm/plat-s3c/Makefile b/arch/arm/plat-s3c/Makefile
index 4d0299aef7ca..68a3451a2d9d 100644
--- a/arch/arm/plat-s3c/Makefile
+++ b/arch/arm/plat-s3c/Makefile
@@ -16,6 +16,7 @@ obj-y				+= time.o
 obj-y                           += clock.o
 obj-y                           += pwm-clock.o
 obj-y                           += gpio.o
+obj-y                           += gpio-config.o
 
 # devices
 
diff --git a/arch/arm/plat-s3c/gpio-config.c b/arch/arm/plat-s3c/gpio-config.c
new file mode 100644
index 000000000000..7642b975a998
--- /dev/null
+++ b/arch/arm/plat-s3c/gpio-config.c
@@ -0,0 +1,163 @@
+/* linux/arch/arm/plat-s3c/gpio-config.c
+ *
+ * Copyright 2008 Openmoko, Inc.
+ * Copyright 2008 Simtec Electronics
+ *      Ben Dooks <ben@simtec.co.uk>
+ *      http://armlinux.simtec.co.uk/
+ *
+ * S3C series GPIO configuration 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/gpio.h>
+#include <linux/io.h>
+
+#include <mach/gpio-core.h>
+#include <plat/gpio-cfg.h>
+#include <plat/gpio-cfg-helpers.h>
+
+int s3c_gpio_cfgpin(unsigned int pin, unsigned int config)
+{
+        struct s3c_gpio_chip *chip = s3c_gpiolib_getchip(pin);
+        unsigned long flags;
+        int offset;
+        int ret;
+
+        if (!chip)
+                return -EINVAL;
+
+        offset = pin - chip->chip.base;
+
+        local_irq_save(flags);
+        ret = s3c_gpio_do_setcfg(chip, offset, config);
+        local_irq_restore(flags);
+
+        return ret;
+}
+
+int s3c_gpio_setpull(unsigned int pin, s3c_gpio_pull_t pull)
+{
+        struct s3c_gpio_chip *chip = s3c_gpiolib_getchip(pin);
+        unsigned long flags;
+        int offset, ret;
+
+        if (!chip)
+                return -EINVAL;
+
+        offset = pin - chip->chip.base;
+
+        local_irq_save(flags);
+        ret = s3c_gpio_do_setpull(chip, offset, pull);
+        local_irq_restore(flags);
+
+        return ret;
+}
+
+#ifdef CONFIG_S3C_GPIO_CFG_S3C24XX
+int s3c_gpio_setcfg_s3c24xx_banka(struct s3c_gpio_chip *chip,
+                                  unsigned int off, unsigned int cfg)
+{
+        void __iomem *reg = chip->base;
+        unsigned int shift = off;
+        u32 con;
+
+        if (s3c_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;
+}
+
+int s3c_gpio_setcfg_s3c24xx(struct s3c_gpio_chip *chip,
+                            unsigned int off, unsigned int cfg)
+{
+        void __iomem *reg = chip->base;
+        unsigned int shift = off * 2;
+        u32 con;
+
+        if (s3c_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;
+}
+#endif
+
+#ifdef CONFIG_S3C_GPIO_CFG_S3C64XX
+int s3c_gpio_setcfg_s3c64xx_4bit(struct s3c_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 (s3c_gpio_is_cfg_special(cfg)) {
+                cfg &= 0xf;
+                cfg <<= shift;
+        }
+
+        con = __raw_readl(reg);
+        con &= ~(0xf << shift);
+        con |= cfg;
+        __raw_writel(con, reg);
+
+        return 0;
+}
+#endif /* CONFIG_S3C_GPIO_CFG_S3C64XX */
+
+#ifdef CONFIG_S3C_GPIO_PULL_UPDOWN
+int s3c_gpio_setpull_updown(struct s3c_gpio_chip *chip,
+                            unsigned int off, s3c_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;
+}
+
+s3c_gpio_pull_t s3c_gpio_getpull_updown(struct s3c_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 s3c_gpio_pull_t)pup;
+}
+#endif
diff --git a/arch/arm/plat-s3c/include/plat/gpio-cfg-helpers.h b/arch/arm/plat-s3c/include/plat/gpio-cfg-helpers.h
new file mode 100644
index 000000000000..652e2bbdaa20
--- /dev/null
+++ b/arch/arm/plat-s3c/include/plat/gpio-cfg-helpers.h
@@ -0,0 +1,176 @@
+/* linux/arch/arm/plat-s3c/include/plat/gpio-cfg-helper.h
+ *
+ * Copyright 2008 Openmoko, Inc.
+ * Copyright 2008 Simtec Electronics
+ *      http://armlinux.simtec.co.uk/
+ *      Ben Dooks <ben@simtec.co.uk>
+ *
+ * S3C Platform - GPIO pin configuration helper definitions
+ *
+ * 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.
+*/
+
+/* This is meant for core cpu support, machine or other driver files
+ * should not be including this header.
+ */
+
+#ifndef __PLAT_GPIO_CFG_HELPERS_H
+#define __PLAT_GPIO_CFG_HELPERS_H __FILE__
+
+/* As a note, all gpio configuration functions are entered exclusively, either
+ * with the relevant lock held or the system prevented from doing anything else
+ * by disabling interrupts.
+*/
+
+static inline int s3c_gpio_do_setcfg(struct s3c_gpio_chip *chip,
+                                     unsigned int off, unsigned int config)
+{
+        return (chip->config->set_config)(chip, off, config);
+}
+
+static inline int s3c_gpio_do_setpull(struct s3c_gpio_chip *chip,
+                                      unsigned int off, s3c_gpio_pull_t pull)
+{
+        return (chip->config->set_pull)(chip, off, pull);
+}
+
+/**
+ * s3c_gpio_setcfg_s3c24xx - S3C24XX 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
+*/
+extern int s3c_gpio_setcfg_s3c24xx(struct s3c_gpio_chip *chip,
+                                   unsigned int off, unsigned int cfg);
+
+/**
+ * s3c_gpio_setcfg_s3c24xx_a - 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.
+*/
+extern int s3c_gpio_setcfg_s3c24xx_a(struct s3c_gpio_chip *chip,
+                                     unsigned int off, unsigned int cfg);
+
+/**
+ * s3c_gpio_setcfg_s3c64xx_4bit - S3C64XX 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 (dependant 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 seperate set of functions for
+ * each case.
+*/
+extern int s3c_gpio_setcfg_s3c64xx_4bit(struct s3c_gpio_chip *chip,
+                                        unsigned int off, unsigned int cfg);
+
+
+/* Pull-{up,down} resistor controls.
+ *
+ * S3C2410,S3C2440,S3C24A0 = Pull-UP,
+ * S3C2412,S3C2413 = Pull-Down
+ * S3C6400,S3C6410 = Pull-Both [None,Down,Up,Undef]
+ * S3C2443 = Pull-Both [not same as S3C6400]
+ */
+
+/**
+ * s3c_gpio_setpull_1up() - Pull configuration for choice of up or none.
+ * @chip: The gpio chip that is being configured.
+ * @off: The offset for the GPIO being configured.
+ * @param: pull: The pull mode being requested.
+ *
+ * This is a helper function for the case where we have GPIOs with one
+ * bit configuring the presence of a pull-up resistor.
+ */
+extern int s3c_gpio_setpull_1up(struct s3c_gpio_chip *chip,
+                                unsigned int off, s3c_gpio_pull_t pull);
+
+/**
+ * s3c_gpio_setpull_1down() - Pull configuration for choice of down or none
+ * @chip: The gpio chip that is being configured
+ * @off: The offset for the GPIO being configured
+ * @param: pull: The pull mode being requested
+ *
+ * This is a helper function for the case where we have GPIOs with one
+ * bit configuring the presence of a pull-down resistor.
+ */
+extern int s3c_gpio_setpull_1down(struct s3c_gpio_chip *chip,
+                                  unsigned int off, s3c_gpio_pull_t pull);
+
+/**
+ * s3c_gpio_setpull_upown() - Pull configuration for choice of up, down or none
+ * @chip: The gpio chip that is being configured.
+ * @off: The offset for the GPIO being configured.
+ * @param: pull: The pull mode being requested.
+ *
+ * This is a helper function for the case where we have GPIOs with two
+ * bits configuring the presence of a pull resistor, in the following
+ * order:
+ *      00 = No pull resistor connected
+ *      01 = Pull-up resistor connected
+ *      10 = Pull-down resistor connected
+ */
+extern int s3c_gpio_setpull_updown(struct s3c_gpio_chip *chip,
+                                   unsigned int off, s3c_gpio_pull_t pull);
+
+
+/**
+ * s3c_gpio_getpull_updown() - Get configuration for choice of up, down or none
+ * @chip: The gpio chip that the GPIO pin belongs to
+ * @off: The offset to the pin to get the configuration of.
+ *
+ * This helper function reads the state of the pull-{up,down} resistor for the
+ * given GPIO in the same case as s3c_gpio_setpull_upown.
+*/
+extern s3c_gpio_pull_t s3c_gpio_getpull_updown(struct s3c_gpio_chip *chip,
+                                               unsigned int off);
+
+/**
+ * s3c_gpio_setpull_s3c2443() - Pull configuration for s3c2443.
+ * @chip: The gpio chip that is being configured.
+ * @off: The offset for the GPIO being configured.
+ * @param: pull: The pull mode being requested.
+ *
+ * This is a helper function for the case where we have GPIOs with two
+ * bits configuring the presence of a pull resistor, in the following
+ * order:
+ *      00 = Pull-up resistor connected
+ *      10 = Pull-down resistor connected
+ *      x1 = No pull up resistor
+ */
+extern int s3c_gpio_setpull_s3c2443(struct s3c_gpio_chip *chip,
+                                    unsigned int off, s3c_gpio_pull_t pull);
+
+/**
+ * s3c_gpio_getpull_s3c2443() - Get configuration for s3c2443 pull resistors
+ * @chip: The gpio chip that the GPIO pin belongs to.
+ * @off: The offset to the pin to get the configuration of.
+ *
+ * This helper function reads the state of the pull-{up,down} resistor for the
+ * given GPIO in the same case as s3c_gpio_setpull_upown.
+*/
+extern s3c_gpio_pull_t s3c_gpio_getpull_s3c24xx(struct s3c_gpio_chip *chip,
+                                                unsigned int off);
+
+#endif /* __PLAT_GPIO_CFG_HELPERS_H */
+
diff --git a/arch/arm/plat-s3c/include/plat/gpio-cfg.h b/arch/arm/plat-s3c/include/plat/gpio-cfg.h
new file mode 100644
index 000000000000..29cd6a86cade
--- /dev/null
+++ b/arch/arm/plat-s3c/include/plat/gpio-cfg.h
@@ -0,0 +1,110 @@
+/* linux/arch/arm/plat-s3c/include/plat/gpio-cfg.h
+ *
+ * Copyright 2008 Openmoko, Inc.
+ * Copyright 2008 Simtec Electronics
+ *      http://armlinux.simtec.co.uk/
+ *      Ben Dooks <ben@simtec.co.uk>
+ *
+ * S3C Platform - GPIO pin configuration
+ *
+ * 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.
+*/
+
+/* This file contains the necessary definitions to get the basic gpio
+ * pin configuration done such as setting a pin to input or output or
+ * changing the pull-{up,down} configurations.
+ */
+
+/* Note, this interface is being added to the s3c64xx arch first and will
+ * be added to the s3c24xx systems later.
+ */
+
+#ifndef __PLAT_GPIO_CFG_H
+#define __PLAT_GPIO_CFG_H __FILE__
+
+typedef unsigned int __bitwise__ s3c_gpio_pull_t;
+
+/* forward declaration if gpio-core.h hasn't been included */
+struct s3c_gpio_chip;
+
+/**
+ * struct s3c_gpio_cfg GPIO configuration
+ * @cfg_eint: Configuration setting when used for external interrupt source
+ * @get_pull: Read the current pull configuration for the GPIO
+ * @set_pull: Set the current pull configuraiton for the GPIO
+ * @set_config: Set the current configuration for the GPIO
+ * @get_config: Read the current configuration for the GPIO
+ *
+ * Each chip can have more than one type of GPIO bank available and some
+ * have different capabilites even when they have the same control register
+ * layouts. Provide an point to vector control routine and provide any
+ * per-bank configuration information that other systems such as the
+ * external interrupt code will need.
+ */
+struct s3c_gpio_cfg {
+        unsigned int    cfg_eint;
+
+        s3c_gpio_pull_t (*get_pull)(struct s3c_gpio_chip *chip, unsigned offs);
+        int             (*set_pull)(struct s3c_gpio_chip *chip, unsigned offs,
+                                    s3c_gpio_pull_t pull);
+
+        unsigned (*get_config)(struct s3c_gpio_chip *chip, unsigned offs);
+        int      (*set_config)(struct s3c_gpio_chip *chip, unsigned offs,
+                               unsigned config);
+};
+
+#define S3C_GPIO_SPECIAL_MARK   (0xfffffff0)
+#define S3C_GPIO_SPECIAL(x)     (S3C_GPIO_SPECIAL_MARK | (x))
+
+/* Defines for generic pin configurations */
+#define S3C_GPIO_INPUT  (S3C_GPIO_SPECIAL(0))
+#define S3C_GPIO_OUTPUT (S3C_GPIO_SPECIAL(1))
+#define S3C_GPIO_SFN(x) (S3C_GPIO_SPECIAL(x))
+
+#define s3c_gpio_is_cfg_special(_cfg) \
+        (((_cfg) & S3C_GPIO_SPECIAL_MARK) == S3C_GPIO_SPECIAL_MARK)
+
+/**
+ * s3c_gpio_cfgpin() - Change the GPIO function of a pin.
+ * @pin pin The pin number to configure.
+ * @pin to The configuration for the pin's function.
+ *
+ * Configure which function is actually connected to the external
+ * pin, such as an gpio input, output or some form of special function
+ * connected to an internal peripheral block.
+ */
+extern int s3c_gpio_cfgpin(unsigned int pin, unsigned int to);
+
+/* Define values for the pull-{up,down} available for each gpio pin.
+ *
+ * These values control the state of the weak pull-{up,down} resistors
+ * available on most pins on the S3C series. Not all chips support both
+ * up or down settings, and it may be dependant on the chip that is being
+ * used to whether the particular mode is available.
+ */
+#define S3C_GPIO_PULL_NONE      ((__force s3c_gpio_pull_t)0x00)
+#define S3C_GPIO_PULL_DOWN      ((__force s3c_gpio_pull_t)0x01)
+#define S3C_GPIO_PULL_UP        ((__force s3c_gpio_pull_t)0x02)
+
+/**
+ * s3c_gpio_setpull() - set the state of a gpio pin pull resistor
+ * @pin: The pin number to configure the pull resistor.
+ * @pull: The configuration for the pull resistor.
+ *
+ * This function sets the state of the pull-{up,down} resistor for the
+ * specified pin. It will return 0 if successfull, or a negative error
+ * code if the pin cannot support the requested pull setting.
+*/
+extern int s3c_gpio_setpull(unsigned int pin, s3c_gpio_pull_t pull);
+
+/**
+ * s3c_gpio_getpull() - get the pull resistor state of a gpio pin
+ * @pin: The pin number to get the settings for
+ *
+ * Read the pull resistor value for the specified pin.
+*/
+extern s3c_gpio_pull_t s3c_gpio_getpull(unsigned int pin);
+
+#endif /* __PLAT_GPIO_CFG_H */
diff --git a/arch/arm/plat-s3c/include/plat/gpio-core.h b/arch/arm/plat-s3c/include/plat/gpio-core.h
index ad68b32a7f9d..2fc60a580ac8 100644
--- a/arch/arm/plat-s3c/include/plat/gpio-core.h
+++ b/arch/arm/plat-s3c/include/plat/gpio-core.h
@@ -20,16 +20,20 @@
  * specific code.
 */
 
+struct s3c_gpio_cfg;
+
 /**
  * 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.
+ * @config: special function and pull-resistor control information.
  *
  * This wrapper provides the necessary information for the Samsung
  * specific gpios being registered with gpiolib.
  */
 struct s3c_gpio_chip {
         struct gpio_chip        chip;
+        struct s3c_gpio_cfg     *config;
         void __iomem            *base;
 };
 
@@ -48,7 +52,6 @@ static inline struct s3c_gpio_chip *to_s3c_gpio(struct gpio_chip *gpc)
  */
 extern void s3c_gpiolib_add(struct s3c_gpio_chip *chip);
 
-
 /* 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.
@@ -65,8 +68,10 @@ extern struct s3c_gpio_chip *s3c_gpios[S3C_GPIO_END];
 
 static inline struct s3c_gpio_chip *s3c_gpiolib_getchip(unsigned int chip)
 {
-        return s3c_gpios[chip];
+        return (chip < S3C_GPIO_END) ? s3c_gpios[chip] : NULL;
 }
 #else
+/* machine specific code should provide s3c_gpiolib_getchip */
+
 static inline void s3c_gpiolib_track(struct s3c_gpio_chip *chip) { }
 #endif