diff options
Diffstat (limited to 'arch/arm/plat-s3c/include/plat/gpio-cfg.h')
| -rw-r--r-- | arch/arm/plat-s3c/include/plat/gpio-cfg.h | 110 |
1 files changed, 110 insertions, 0 deletions
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 */ |