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Diffstat (limited to 'arch/arm/plat-s3c/include/plat/gpio-cfg.h')
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diff --git a/arch/arm/plat-s3c/include/plat/gpio-cfg.h b/arch/arm/plat-s3c/include/plat/gpio-cfg.h
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+++ b/arch/arm/plat-s3c/include/plat/gpio-cfg.h
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+/* 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 */