original_kernel/include/asm-arm/arch-davinci/gpio.h

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/*
* TI DaVinci GPIO Support
*
* Copyright (c) 2006 David Brownell
* Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#ifndef __DAVINCI_GPIO_H
#define __DAVINCI_GPIO_H
#include <linux/io.h>
#include <asm/hardware.h>
/*
* basic gpio routines
*
* board-specific init should be done by arch/.../.../board-XXX.c (maybe
* initializing banks together) rather than boot loaders; kexec() won't
* go through boot loaders.
*
* the gpio clock will be turned on when gpios are used, and you may also
* need to pay attention to PINMUX0 and PINMUX1 to be sure those pins are
* used as gpios, not with other peripherals.
*
* GPIOs are numbered 0..(DAVINCI_N_GPIO-1). For documentation, and maybe
* for later updates, code should write GPIO(N) or:
* - GPIOV18(N) for 1.8V pins, N in 0..53; same as GPIO(0)..GPIO(53)
* - GPIOV33(N) for 3.3V pins, N in 0..17; same as GPIO(54)..GPIO(70)
*
* For GPIO IRQs use gpio_to_irq(GPIO(N)) or gpio_to_irq(GPIOV33(N)) etc
* for now, that's != GPIO(N)
*/
#define GPIO(X) (X) /* 0 <= X <= 70 */
#define GPIOV18(X) (X) /* 1.8V i/o; 0 <= X <= 53 */
#define GPIOV33(X) ((X)+54) /* 3.3V i/o; 0 <= X <= 17 */
struct gpio_controller {
u32 dir;
u32 out_data;
u32 set_data;
u32 clr_data;
u32 in_data;
u32 set_rising;
u32 clr_rising;
u32 set_falling;
u32 clr_falling;
u32 intstat;
};
/* The __gpio_to_controller() and __gpio_mask() functions inline to constants
* with constant parameters; or in outlined code they execute at runtime.
*
* You'd access the controller directly when reading or writing more than
* one gpio value at a time, and to support wired logic where the value
* being driven by the cpu need not match the value read back.
*
* These are NOT part of the cross-platform GPIO interface
*/
static inline struct gpio_controller *__iomem
__gpio_to_controller(unsigned gpio)
{
void *__iomem ptr;
if (gpio < 32)
ptr = (void *__iomem)IO_ADDRESS(DAVINCI_GPIO_BASE + 0x10);
else if (gpio < 64)
ptr = (void *__iomem)IO_ADDRESS(DAVINCI_GPIO_BASE + 0x38);
else if (gpio < DAVINCI_N_GPIO)
ptr = (void *__iomem)IO_ADDRESS(DAVINCI_GPIO_BASE + 0x60);
else
ptr = NULL;
return ptr;
}
static inline u32 __gpio_mask(unsigned gpio)
{
return 1 << (gpio % 32);
}
/* The get/set/clear functions will inline when called with constant
* parameters, for low-overhead bitbanging. Illegal constant parameters
* cause link-time errors.
*
* Otherwise, calls with variable parameters use outlined functions.
*/
extern int __error_inval_gpio(void);
extern void __gpio_set(unsigned gpio, int value);
extern int __gpio_get(unsigned gpio);
static inline void gpio_set_value(unsigned gpio, int value)
{
if (__builtin_constant_p(value)) {
struct gpio_controller *__iomem g;
u32 mask;
if (gpio >= DAVINCI_N_GPIO)
__error_inval_gpio();
g = __gpio_to_controller(gpio);
mask = __gpio_mask(gpio);
if (value)
__raw_writel(mask, &g->set_data);
else
__raw_writel(mask, &g->clr_data);
return;
}
__gpio_set(gpio, value);
}
/* Returns zero or nonzero; works for gpios configured as inputs OR
* as outputs.
*
* NOTE: changes in reported values are synchronized to the GPIO clock.
* This is most easily seen after calling gpio_set_value() and then immediatly
* gpio_get_value(), where the gpio_get_value() would return the old value
* until the GPIO clock ticks and the new value gets latched.
*/
static inline int gpio_get_value(unsigned gpio)
{
struct gpio_controller *__iomem g;
if (!__builtin_constant_p(gpio))
return __gpio_get(gpio);
if (gpio >= DAVINCI_N_GPIO)
return __error_inval_gpio();
g = __gpio_to_controller(gpio);
return !!(__gpio_mask(gpio) & __raw_readl(&g->in_data));
}
/* powerup default direction is IN */
extern int gpio_direction_input(unsigned gpio);
extern int gpio_direction_output(unsigned gpio, int value);
#include <asm-generic/gpio.h> /* cansleep wrappers */
extern int gpio_request(unsigned gpio, const char *tag);
extern void gpio_free(unsigned gpio);
static inline int gpio_to_irq(unsigned gpio)
{
return DAVINCI_N_AINTC_IRQ + gpio;
}
static inline int irq_to_gpio(unsigned irq)
{
return irq - DAVINCI_N_AINTC_IRQ;
}
#endif /* __DAVINCI_GPIO_H */