1/* linux/arch/arm/plat-s3c/include/plat/gpio-cfg.h 2 * 3 * Copyright 2008 Openmoko, Inc. 4 * Copyright 2008 Simtec Electronics 5 * http://armlinux.simtec.co.uk/ 6 * Ben Dooks <ben@simtec.co.uk> 7 * 8 * S3C Platform - GPIO pin configuration 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License version 2 as 12 * published by the Free Software Foundation. 13*/ 14 15/* This file contains the necessary definitions to get the basic gpio 16 * pin configuration done such as setting a pin to input or output or 17 * changing the pull-{up,down} configurations. 18 */ 19 20/* Note, this interface is being added to the s3c64xx arch first and will 21 * be added to the s3c24xx systems later. 22 */ 23 24#ifndef __PLAT_GPIO_CFG_H 25#define __PLAT_GPIO_CFG_H __FILE__ 26 27#include <linux/types.h> 28 29typedef unsigned int __bitwise samsung_gpio_pull_t; 30 31/* forward declaration if gpio-core.h hasn't been included */ 32struct samsung_gpio_chip; 33 34/** 35 * struct samsung_gpio_cfg GPIO configuration 36 * @cfg_eint: Configuration setting when used for external interrupt source 37 * @get_pull: Read the current pull configuration for the GPIO 38 * @set_pull: Set the current pull configuration for the GPIO 39 * @set_config: Set the current configuration for the GPIO 40 * @get_config: Read the current configuration for the GPIO 41 * 42 * Each chip can have more than one type of GPIO bank available and some 43 * have different capabilites even when they have the same control register 44 * layouts. Provide an point to vector control routine and provide any 45 * per-bank configuration information that other systems such as the 46 * external interrupt code will need. 47 * 48 * @sa samsung_gpio_cfgpin 49 * @sa s3c_gpio_getcfg 50 * @sa s3c_gpio_setpull 51 * @sa s3c_gpio_getpull 52 */ 53struct samsung_gpio_cfg { 54 unsigned int cfg_eint; 55 56 samsung_gpio_pull_t (*get_pull)(struct samsung_gpio_chip *chip, unsigned offs); 57 int (*set_pull)(struct samsung_gpio_chip *chip, unsigned offs, 58 samsung_gpio_pull_t pull); 59 60 unsigned (*get_config)(struct samsung_gpio_chip *chip, unsigned offs); 61 int (*set_config)(struct samsung_gpio_chip *chip, unsigned offs, 62 unsigned config); 63}; 64 65#define S3C_GPIO_SPECIAL_MARK (0xfffffff0) 66#define S3C_GPIO_SPECIAL(x) (S3C_GPIO_SPECIAL_MARK | (x)) 67 68/* Defines for generic pin configurations */ 69#define S3C_GPIO_INPUT (S3C_GPIO_SPECIAL(0)) 70#define S3C_GPIO_OUTPUT (S3C_GPIO_SPECIAL(1)) 71#define S3C_GPIO_SFN(x) (S3C_GPIO_SPECIAL(x)) 72 73#define samsung_gpio_is_cfg_special(_cfg) \ 74 (((_cfg) & S3C_GPIO_SPECIAL_MARK) == S3C_GPIO_SPECIAL_MARK) 75 76/** 77 * s3c_gpio_cfgpin() - Change the GPIO function of a pin. 78 * @pin pin The pin number to configure. 79 * @to to The configuration for the pin's function. 80 * 81 * Configure which function is actually connected to the external 82 * pin, such as an gpio input, output or some form of special function 83 * connected to an internal peripheral block. 84 * 85 * The @to parameter can be one of the generic S3C_GPIO_INPUT, S3C_GPIO_OUTPUT 86 * or S3C_GPIO_SFN() to indicate one of the possible values that the helper 87 * will then generate the correct bit mask and shift for the configuration. 88 * 89 * If a bank of GPIOs all needs to be set to special-function 2, then 90 * the following code will work: 91 * 92 * for (gpio = start; gpio < end; gpio++) 93 * s3c_gpio_cfgpin(gpio, S3C_GPIO_SFN(2)); 94 * 95 * The @to parameter can also be a specific value already shifted to the 96 * correct position in the control register, although these are discouraged 97 * in newer kernels and are only being kept for compatibility. 98 */ 99extern int s3c_gpio_cfgpin(unsigned int pin, unsigned int to); 100 101/** 102 * s3c_gpio_getcfg - Read the current function for a GPIO pin 103 * @pin: The pin to read the configuration value for. 104 * 105 * Read the configuration state of the given @pin, returning a value that 106 * could be passed back to s3c_gpio_cfgpin(). 107 * 108 * @sa s3c_gpio_cfgpin 109 */ 110extern unsigned s3c_gpio_getcfg(unsigned int pin); 111 112/** 113 * s3c_gpio_cfgpin_range() - Change the GPIO function for configuring pin range 114 * @start: The pin number to start at 115 * @nr: The number of pins to configure from @start. 116 * @cfg: The configuration for the pin's function 117 * 118 * Call s3c_gpio_cfgpin() for the @nr pins starting at @start. 119 * 120 * @sa s3c_gpio_cfgpin. 121 */ 122extern int s3c_gpio_cfgpin_range(unsigned int start, unsigned int nr, 123 unsigned int cfg); 124 125/* Define values for the pull-{up,down} available for each gpio pin. 126 * 127 * These values control the state of the weak pull-{up,down} resistors 128 * available on most pins on the S3C series. Not all chips support both 129 * up or down settings, and it may be dependent on the chip that is being 130 * used to whether the particular mode is available. 131 */ 132#define S3C_GPIO_PULL_NONE ((__force samsung_gpio_pull_t)0x00) 133#define S3C_GPIO_PULL_DOWN ((__force samsung_gpio_pull_t)0x01) 134#define S3C_GPIO_PULL_UP ((__force samsung_gpio_pull_t)0x02) 135 136/** 137 * s3c_gpio_setpull() - set the state of a gpio pin pull resistor 138 * @pin: The pin number to configure the pull resistor. 139 * @pull: The configuration for the pull resistor. 140 * 141 * This function sets the state of the pull-{up,down} resistor for the 142 * specified pin. It will return 0 if successful, or a negative error 143 * code if the pin cannot support the requested pull setting. 144 * 145 * @pull is one of S3C_GPIO_PULL_NONE, S3C_GPIO_PULL_DOWN or S3C_GPIO_PULL_UP. 146*/ 147extern int s3c_gpio_setpull(unsigned int pin, samsung_gpio_pull_t pull); 148 149/** 150 * s3c_gpio_getpull() - get the pull resistor state of a gpio pin 151 * @pin: The pin number to get the settings for 152 * 153 * Read the pull resistor value for the specified pin. 154*/ 155extern samsung_gpio_pull_t s3c_gpio_getpull(unsigned int pin); 156 157/* configure `all` aspects of an gpio */ 158 159/** 160 * s3c_gpio_cfgall_range() - configure range of gpio functtion and pull. 161 * @start: The gpio number to start at. 162 * @nr: The number of gpio to configure from @start. 163 * @cfg: The configuration to use 164 * @pull: The pull setting to use. 165 * 166 * Run s3c_gpio_cfgpin() and s3c_gpio_setpull() over the gpio range starting 167 * @gpio and running for @size. 168 * 169 * @sa s3c_gpio_cfgpin 170 * @sa s3c_gpio_setpull 171 * @sa s3c_gpio_cfgpin_range 172 */ 173extern int s3c_gpio_cfgall_range(unsigned int start, unsigned int nr, 174 unsigned int cfg, samsung_gpio_pull_t pull); 175 176static inline int s3c_gpio_cfgrange_nopull(unsigned int pin, unsigned int size, 177 unsigned int cfg) 178{ 179 return s3c_gpio_cfgall_range(pin, size, cfg, S3C_GPIO_PULL_NONE); 180} 181 182#endif /* __PLAT_GPIO_CFG_H */ 183