diff options
author | Ben Dooks <ben-linux@fluff.org> | 2010-01-18 11:22:38 +0900 |
---|---|---|
committer | Ben Dooks <ben-linux@fluff.org> | 2010-01-19 18:37:19 +0900 |
commit | 4f2b617aff8147338faa0d5ed7b57636076671bf (patch) | |
tree | 86d4d981b6863eb50d8c534efbf586e45e22f55f /arch/arm/plat-samsung/gpio.c | |
parent | 67866fb38680d85cbd13c7bb468fb89f16e026d1 (diff) |
ARM: SAMSUNG: Move gpiolib support in gpio.c to plat-samsung
Move the gpio.c code containing the core gpiolib and GPIO support to
plat-samsung from plat-s3c as it is used by all current Samsung SoCs.
Note, we didn't move this to gpiolib.c as it contains code that is not
strictly for gpiolib support and the 4bit code is already called gpiolib.c
so make the change easier by not renaming both files in one go.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Diffstat (limited to 'arch/arm/plat-samsung/gpio.c')
-rw-r--r-- | arch/arm/plat-samsung/gpio.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/arch/arm/plat-samsung/gpio.c b/arch/arm/plat-samsung/gpio.c new file mode 100644 index 00000000000..5ff24e0f9f8 --- /dev/null +++ b/arch/arm/plat-samsung/gpio.c @@ -0,0 +1,156 @@ +/* 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 <mach/gpio-core.h> + +#ifdef CONFIG_S3C_GPIO_TRACK +struct s3c_gpio_chip *s3c_gpios[S3C_GPIO_END]; + +static __init void s3c_gpiolib_track(struct s3c_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 */ + +/* 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; + int ret; + + 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; + +#ifdef CONFIG_PM + if (chip->pm != NULL) { + if (!chip->pm->save || !chip->pm->resume) + printk(KERN_ERR "gpio: %s has missing PM functions\n", + gc->label); + } else + printk(KERN_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); +} |