- 根目录:
- arch
- arm
- plat-samsung
- include
- plat
- gpio-core.h
/* 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 GPIOCON_OFF (0x00)
#define GPIODAT_OFF (0x04)
#define con_4bit_shift(__off) ((__off) * 4)
/* 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;
/**
* struct s3c_gpio_pm - power management (suspend/resume) information
* @save: Routine to save the state of the GPIO block
* @resume: Routine to resume the GPIO block.
*/
struct s3c_gpio_pm {
void (*save)(struct s3c_gpio_chip *chip);
void (*resume)(struct s3c_gpio_chip *chip);
};
struct s3c_gpio_cfg;
/**
* 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.
* @group: The group register number for gpio interrupt support.
* @irq_base: The base irq number.
* @config: special function and pull-resistor control information.
* @lock: Lock for exclusive access to this gpio bank.
* @pm_save: Save information for suspend/resume support.
*
* This wrapper provides the necessary information for the Samsung
* specific gpios being registered with gpiolib.
*
* The lock protects each gpio bank from multiple access of the shared
* configuration registers, or from reading of data whilst another thread
* is writing to the register set.
*
* Each chip has its own lock to avoid any contention between different
* CPU cores trying to get one lock for different GPIO banks, where each
* bank of GPIO has its own register space and configuration registers.
*/
struct s3c_gpio_chip {
struct gpio_chip chip;
struct s3c_gpio_cfg *config;
struct s3c_gpio_pm *pm;
void __iomem *base;
int irq_base;
int group;
spinlock_t lock;
#ifdef CONFIG_PM
u32 pm_save[4];
#endif
};
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);
/* CONFIG_S3C_GPIO_TRACK enables the tracking of the s3c specific gpios
* for use with the configuration calls, and other parts of the s3c gpiolib
* support code.
*
* Not all s3c support code will need this, as some configurations of cpu
* may only support one or two different configuration options and have an
* easy gpio to s3c_gpio_chip mapping function. If this is the case, then
* the machine support file should provide its own s3c_gpiolib_getchip()
* and any other necessary functions.
*/
/**
* samsung_gpiolib_add_4bit_chips - 4bit single register GPIO config.
* @chip: The gpio chip that is being configured.
* @nr_chips: The no of chips (gpio ports) for the GPIO being configured.
*
* This helper deal with the GPIO cases where the control register has 4 bits
* of control per GPIO, generally in the form of:
* 0000 = Input
* 0001 = Output
* others = Special functions (dependent on bank)
*
* Note, since the code to deal with the case where there are two control
* registers instead of one, we do not have a separate set of function
* (samsung_gpiolib_add_4bit2_chips)for each case.
*/
extern void samsung_gpiolib_add_4bit_chips(struct s3c_gpio_chip *chip,
int nr_chips);
extern void samsung_gpiolib_add_4bit2_chips(struct s3c_gpio_chip *chip,
int nr_chips);
extern void samsung_gpiolib_add_2bit_chips(struct s3c_gpio_chip *chip,
int nr_chips);
extern void samsung_gpiolib_add_4bit(struct s3c_gpio_chip *chip);
extern void samsung_gpiolib_add_4bit2(struct s3c_gpio_chip *chip);
/**
* samsung_gpiolib_to_irq - convert gpio pin to irq number
* @chip: The gpio chip that the pin belongs to.
* @offset: The offset of the pin in the chip.
*
* This helper returns the irq number calculated from the chip->irq_base and
* the provided offset.
*/
extern int samsung_gpiolib_to_irq(struct gpio_chip *chip, unsigned int offset);
/* exported for core SoC support to change */
extern struct s3c_gpio_cfg s3c24xx_gpiocfg_default;
#ifdef CONFIG_S3C_GPIO_TRACK
extern struct s3c_gpio_chip *s3c_gpios[S3C_GPIO_END];
static inline struct s3c_gpio_chip *s3c_gpiolib_getchip(unsigned int chip)
{
return (chip < S3C_GPIO_END) ? s3c_gpios[chip] : NULL;
}
#else
/* machine specific code should provide s3c_gpiolib_getchip */
#include <mach/gpio-track.h>
static inline void s3c_gpiolib_track(struct s3c_gpio_chip *chip) { }
#endif
#ifdef CONFIG_PM
extern struct s3c_gpio_pm s3c_gpio_pm_1bit;
extern struct s3c_gpio_pm s3c_gpio_pm_2bit;
extern struct s3c_gpio_pm s3c_gpio_pm_4bit;
#define __gpio_pm(x) x
#else
#define s3c_gpio_pm_1bit NULL
#define s3c_gpio_pm_2bit NULL
#define s3c_gpio_pm_4bit NULL
#define __gpio_pm(x) NULL
#endif /* CONFIG_PM */
/* locking wrappers to deal with multiple access to the same gpio bank */
#define s3c_gpio_lock(_oc, _fl) spin_lock_irqsave(&(_oc)->lock, _fl)
#define s3c_gpio_unlock(_oc, _fl) spin_unlock_irqrestore(&(_oc)->lock, _fl)