linux/arch/arm/mach-davinci/include/mach/gpio.h

89 lines
2.4 KiB
C

/*
* 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 <asm-generic/gpio.h>
#define __ARM_GPIOLIB_COMPLEX
/* The inline versions use the static inlines in the driver header */
#include "gpio-davinci.h"
/*
* The get/set/clear functions will inline when called with constant
* parameters referencing built-in GPIOs, for low-overhead bitbanging.
*
* gpio_set_value() will inline only on traditional Davinci style controllers
* with distinct set/clear registers.
*
* Otherwise, calls with variable parameters or referencing external
* GPIOs (e.g. on GPIO expander chips) use outlined functions.
*/
static inline void gpio_set_value(unsigned gpio, int value)
{
if (__builtin_constant_p(value) && gpio < davinci_soc_info.gpio_num) {
struct davinci_gpio_controller *ctlr;
u32 mask;
ctlr = __gpio_to_controller(gpio);
if (ctlr->set_data != ctlr->clr_data) {
mask = __gpio_mask(gpio);
if (value)
__raw_writel(mask, ctlr->set_data);
else
__raw_writel(mask, ctlr->clr_data);
return;
}
}
__gpio_set_value(gpio, value);
}
/* Returns zero or nonzero; works for gpios configured as inputs OR
* as outputs, at least for built-in GPIOs.
*
* NOTE: for built-in GPIOs, changes in reported values are synchronized
* to the GPIO clock. This is easily seen after calling gpio_set_value()
* and then immediately gpio_get_value(), where the gpio_get_value() will
* return the old value until the GPIO clock ticks and the new value gets
* latched.
*/
static inline int gpio_get_value(unsigned gpio)
{
struct davinci_gpio_controller *ctlr;
if (!__builtin_constant_p(gpio) || gpio >= davinci_soc_info.gpio_num)
return __gpio_get_value(gpio);
ctlr = __gpio_to_controller(gpio);
return __gpio_mask(gpio) & __raw_readl(ctlr->in_data);
}
static inline int gpio_cansleep(unsigned gpio)
{
if (__builtin_constant_p(gpio) && gpio < davinci_soc_info.gpio_num)
return 0;
else
return __gpio_cansleep(gpio);
}
static inline int irq_to_gpio(unsigned irq)
{
/* don't support the reverse mapping */
return -ENOSYS;
}
#endif /* __DAVINCI_GPIO_H */