diff options
author | Ben Dooks <ben-linux@fluff.org> | 2008-10-31 17:14:31 +0100 |
---|---|---|
committer | Ben Dooks <ben-linux@fluff.org> | 2008-12-16 00:33:20 +0100 |
commit | 7db6c82a37beabef7b76d232e3d20efacd74bd3a (patch) | |
tree | dcd673614883eba53a207aca9f136c6e7b490c4e /arch/arm/plat-s3c | |
parent | [ARM] S3C64XX: Add gpio bank numbering (diff) | |
download | linux-7db6c82a37beabef7b76d232e3d20efacd74bd3a.tar.xz linux-7db6c82a37beabef7b76d232e3d20efacd74bd3a.zip |
[ARM] S3C: Move common GPIO code from plat-s3c24xx
Move the common parts of the GPIO code into plat-s3c
for use with both the s3c24xx and s3c64xx systems.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Diffstat (limited to 'arch/arm/plat-s3c')
-rw-r--r-- | arch/arm/plat-s3c/Makefile | 1 | ||||
-rw-r--r-- | arch/arm/plat-s3c/gpio.c | 128 | ||||
-rw-r--r-- | arch/arm/plat-s3c/include/plat/gpio-core.h | 49 |
3 files changed, 178 insertions, 0 deletions
diff --git a/arch/arm/plat-s3c/Makefile b/arch/arm/plat-s3c/Makefile index b95a9c106467..4d0299aef7ca 100644 --- a/arch/arm/plat-s3c/Makefile +++ b/arch/arm/plat-s3c/Makefile @@ -15,6 +15,7 @@ obj-y += init.o obj-y += time.o obj-y += clock.o obj-y += pwm-clock.o +obj-y += gpio.o # devices diff --git a/arch/arm/plat-s3c/gpio.c b/arch/arm/plat-s3c/gpio.c new file mode 100644 index 000000000000..f035d4550c43 --- /dev/null +++ b/arch/arm/plat-s3c/gpio.c @@ -0,0 +1,128 @@ +/* linux/arch/arm/plat-s3c/gpio.c + * + * Copyright 2008 Simtec Electronics + * Ben Dooks <ben@simtec.co.uk> + * http://armlinux.simtec.co.uk/ + * + * S3C series GPIO core + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. +*/ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/gpio.h> + +#include <plat/gpio-core.h> + +/* Default routines for controlling GPIO, based on the original S3C24XX + * GPIO functions which deal with the case where each gpio bank of the + * chip is as following: + * + * base + 0x00: Control register, 2 bits per gpio + * gpio n: 2 bits starting at (2*n) + * 00 = input, 01 = output, others mean special-function + * base + 0x04: Data register, 1 bit per gpio + * bit n: data bit n +*/ + +static int s3c_gpiolib_input(struct gpio_chip *chip, unsigned offset) +{ + struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip); + void __iomem *base = ourchip->base; + unsigned long flags; + unsigned long con; + + local_irq_save(flags); + + con = __raw_readl(base + 0x00); + con &= ~(3 << (offset * 2)); + + __raw_writel(con, base + 0x00); + + local_irq_restore(flags); + return 0; +} + +static int s3c_gpiolib_output(struct gpio_chip *chip, + unsigned offset, int value) +{ + struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip); + void __iomem *base = ourchip->base; + unsigned long flags; + unsigned long dat; + unsigned long con; + + local_irq_save(flags); + + dat = __raw_readl(base + 0x04); + dat &= ~(1 << offset); + if (value) + dat |= 1 << offset; + __raw_writel(dat, base + 0x04); + + con = __raw_readl(base + 0x00); + con &= ~(3 << (offset * 2)); + con |= 1 << (offset * 2); + + __raw_writel(con, base + 0x00); + __raw_writel(dat, base + 0x04); + + local_irq_restore(flags); + return 0; +} + +static void s3c_gpiolib_set(struct gpio_chip *chip, + unsigned offset, int value) +{ + struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip); + void __iomem *base = ourchip->base; + unsigned long flags; + unsigned long dat; + + local_irq_save(flags); + + dat = __raw_readl(base + 0x04); + dat &= ~(1 << offset); + if (value) + dat |= 1 << offset; + __raw_writel(dat, base + 0x04); + + local_irq_restore(flags); +} + +static int s3c_gpiolib_get(struct gpio_chip *chip, unsigned offset) +{ + struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip); + unsigned long val; + + val = __raw_readl(ourchip->base + 0x04); + val >>= offset; + val &= 1; + + return val; +} + +__init void s3c_gpiolib_add(struct s3c_gpio_chip *chip) +{ + struct gpio_chip *gc = &chip->chip; + + BUG_ON(!chip->base); + BUG_ON(!gc->label); + BUG_ON(!gc->ngpio); + + if (!gc->direction_input) + gc->direction_input = s3c_gpiolib_input; + if (!gc->direction_output) + gc->direction_output = s3c_gpiolib_output; + if (!gc->set) + gc->set = s3c_gpiolib_set; + if (!gc->get) + gc->get = s3c_gpiolib_get; + + /* gpiochip_add() prints own failure message on error. */ + gpiochip_add(gc); +} diff --git a/arch/arm/plat-s3c/include/plat/gpio-core.h b/arch/arm/plat-s3c/include/plat/gpio-core.h new file mode 100644 index 000000000000..3cb9105c4811 --- /dev/null +++ b/arch/arm/plat-s3c/include/plat/gpio-core.h @@ -0,0 +1,49 @@ +/* linux/arch/arm/plat-s3c/include/plat/gpio-core.h + * + * Copyright 2008 Simtec Electronics + * http://armlinux.simtec.co.uk/ + * Ben Dooks <ben@simtec.co.uk> + * + * S3C Platform - GPIO core + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. +*/ + +/* Define the core gpiolib support functions that the s3c platforms may + * need to extend or change depending on the hardware and the s3c chip + * selected at build or found at run time. + * + * These definitions are not intended for driver inclusion, there is + * nothing here that should not live outside the platform and core + * specific code. +*/ + +/** + * struct s3c_gpio_chip - wrapper for specific implementation of gpio + * @chip: The chip structure to be exported via gpiolib. + * @base: The base pointer to the gpio configuration registers. + * + * This wrapper provides the necessary information for the Samsung + * specific gpios being registered with gpiolib. + */ +struct s3c_gpio_chip { + struct gpio_chip chip; + void __iomem *base; +}; + +static inline struct s3c_gpio_chip *to_s3c_gpio(struct gpio_chip *gpc) +{ + return container_of(gpc, struct s3c_gpio_chip, chip); +} + +/** s3c_gpiolib_add() - add the s3c specific version of a gpio_chip. + * @chip: The chip to register + * + * This is a wrapper to gpiochip_add() that takes our specific gpio chip + * information and makes the necessary alterations for the platform and + * notes the information for use with the configuration systems and any + * other parts of the system. + */ +extern void s3c_gpiolib_add(struct s3c_gpio_chip *chip); |