linux/arch/m68k/coldfire/gpio.c
Linus Walleij 4693c2493a m68k: coldfire/gpio: Be sure to clamp return value
As we want gpio_chip .get() calls to be able to return negative
error codes and propagate to drivers, we need to go over all
drivers and make sure their return values are clamped to [0,1].
We do this by using the ret = !!(val) design pattern.

Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
2016-01-04 13:25:12 +10:00

187 lines
4.2 KiB
C

/*
* Coldfire generic GPIO support.
*
* (C) Copyright 2009, Steven King <sfking@fdwdc.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; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/io.h>
#include <asm/coldfire.h>
#include <asm/mcfsim.h>
#include <asm/mcfgpio.h>
int __mcfgpio_get_value(unsigned gpio)
{
return mcfgpio_read(__mcfgpio_ppdr(gpio)) & mcfgpio_bit(gpio);
}
EXPORT_SYMBOL(__mcfgpio_get_value);
void __mcfgpio_set_value(unsigned gpio, int value)
{
if (gpio < MCFGPIO_SCR_START) {
unsigned long flags;
MCFGPIO_PORTTYPE data;
local_irq_save(flags);
data = mcfgpio_read(__mcfgpio_podr(gpio));
if (value)
data |= mcfgpio_bit(gpio);
else
data &= ~mcfgpio_bit(gpio);
mcfgpio_write(data, __mcfgpio_podr(gpio));
local_irq_restore(flags);
} else {
if (value)
mcfgpio_write(mcfgpio_bit(gpio),
MCFGPIO_SETR_PORT(gpio));
else
mcfgpio_write(~mcfgpio_bit(gpio),
MCFGPIO_CLRR_PORT(gpio));
}
}
EXPORT_SYMBOL(__mcfgpio_set_value);
int __mcfgpio_direction_input(unsigned gpio)
{
unsigned long flags;
MCFGPIO_PORTTYPE dir;
local_irq_save(flags);
dir = mcfgpio_read(__mcfgpio_pddr(gpio));
dir &= ~mcfgpio_bit(gpio);
mcfgpio_write(dir, __mcfgpio_pddr(gpio));
local_irq_restore(flags);
return 0;
}
EXPORT_SYMBOL(__mcfgpio_direction_input);
int __mcfgpio_direction_output(unsigned gpio, int value)
{
unsigned long flags;
MCFGPIO_PORTTYPE data;
local_irq_save(flags);
data = mcfgpio_read(__mcfgpio_pddr(gpio));
data |= mcfgpio_bit(gpio);
mcfgpio_write(data, __mcfgpio_pddr(gpio));
/* now set the data to output */
if (gpio < MCFGPIO_SCR_START) {
data = mcfgpio_read(__mcfgpio_podr(gpio));
if (value)
data |= mcfgpio_bit(gpio);
else
data &= ~mcfgpio_bit(gpio);
mcfgpio_write(data, __mcfgpio_podr(gpio));
} else {
if (value)
mcfgpio_write(mcfgpio_bit(gpio),
MCFGPIO_SETR_PORT(gpio));
else
mcfgpio_write(~mcfgpio_bit(gpio),
MCFGPIO_CLRR_PORT(gpio));
}
local_irq_restore(flags);
return 0;
}
EXPORT_SYMBOL(__mcfgpio_direction_output);
int __mcfgpio_request(unsigned gpio)
{
return 0;
}
EXPORT_SYMBOL(__mcfgpio_request);
void __mcfgpio_free(unsigned gpio)
{
__mcfgpio_direction_input(gpio);
}
EXPORT_SYMBOL(__mcfgpio_free);
#ifdef CONFIG_GPIOLIB
static int mcfgpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
return __mcfgpio_direction_input(offset);
}
static int mcfgpio_get_value(struct gpio_chip *chip, unsigned offset)
{
return !!__mcfgpio_get_value(offset);
}
static int mcfgpio_direction_output(struct gpio_chip *chip, unsigned offset,
int value)
{
return __mcfgpio_direction_output(offset, value);
}
static void mcfgpio_set_value(struct gpio_chip *chip, unsigned offset,
int value)
{
__mcfgpio_set_value(offset, value);
}
static int mcfgpio_request(struct gpio_chip *chip, unsigned offset)
{
return __mcfgpio_request(offset);
}
static void mcfgpio_free(struct gpio_chip *chip, unsigned offset)
{
__mcfgpio_free(offset);
}
static int mcfgpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
#if defined(MCFGPIO_IRQ_MIN)
if ((offset >= MCFGPIO_IRQ_MIN) && (offset < MCFGPIO_IRQ_MAX))
#else
if (offset < MCFGPIO_IRQ_MAX)
#endif
return MCFGPIO_IRQ_VECBASE + offset;
else
return -EINVAL;
}
static struct bus_type mcfgpio_subsys = {
.name = "gpio",
.dev_name = "gpio",
};
static struct gpio_chip mcfgpio_chip = {
.label = "mcfgpio",
.request = mcfgpio_request,
.free = mcfgpio_free,
.direction_input = mcfgpio_direction_input,
.direction_output = mcfgpio_direction_output,
.get = mcfgpio_get_value,
.set = mcfgpio_set_value,
.to_irq = mcfgpio_to_irq,
.base = 0,
.ngpio = MCFGPIO_PIN_MAX,
};
static int __init mcfgpio_sysinit(void)
{
gpiochip_add(&mcfgpio_chip);
return subsys_system_register(&mcfgpio_subsys, NULL);
}
core_initcall(mcfgpio_sysinit);
#endif