mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-14 23:33:00 +00:00
210 lines
4.7 KiB
C
210 lines
4.7 KiB
C
|
/*
|
||
|
* Copyright (c) 2011 The Chromium OS Authors.
|
||
|
* See file CREDITS for list of people who contributed to this
|
||
|
* project.
|
||
|
*
|
||
|
* 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.
|
||
|
*
|
||
|
* 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.
|
||
|
*
|
||
|
* You should have received a copy of the GNU General Public License
|
||
|
* along with this program; if not, write to the Free Software
|
||
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
|
||
|
* MA 02111-1307 USA
|
||
|
*/
|
||
|
|
||
|
#include <common.h>
|
||
|
#include <asm/gpio.h>
|
||
|
|
||
|
/* Flags for each GPIO */
|
||
|
#define GPIOF_OUTPUT (1 << 0) /* Currently set as an output */
|
||
|
#define GPIOF_HIGH (1 << 1) /* Currently set high */
|
||
|
#define GPIOF_RESERVED (1 << 2) /* Is in use / requested */
|
||
|
|
||
|
struct gpio_state {
|
||
|
const char *label; /* label given by requester */
|
||
|
u8 flags; /* flags (GPIOF_...) */
|
||
|
};
|
||
|
|
||
|
/*
|
||
|
* State of GPIOs
|
||
|
* TODO: Put this into sandbox state
|
||
|
*/
|
||
|
static struct gpio_state state[CONFIG_SANDBOX_GPIO_COUNT];
|
||
|
|
||
|
/* Access routines for GPIO state */
|
||
|
static u8 *get_gpio_flags(unsigned gp)
|
||
|
{
|
||
|
/* assert()'s could be disabled, so make sure we handle that */
|
||
|
assert(gp < ARRAY_SIZE(state));
|
||
|
if (gp >= ARRAY_SIZE(state)) {
|
||
|
static u8 invalid_flags;
|
||
|
printf("sandbox_gpio: error: invalid gpio %u\n", gp);
|
||
|
return &invalid_flags;
|
||
|
}
|
||
|
|
||
|
return &state[gp].flags;
|
||
|
}
|
||
|
|
||
|
static int get_gpio_flag(unsigned gp, int flag)
|
||
|
{
|
||
|
return (*get_gpio_flags(gp) & flag) != 0;
|
||
|
}
|
||
|
|
||
|
static int set_gpio_flag(unsigned gp, int flag, int value)
|
||
|
{
|
||
|
u8 *gpio = get_gpio_flags(gp);
|
||
|
|
||
|
if (value)
|
||
|
*gpio |= flag;
|
||
|
else
|
||
|
*gpio &= ~flag;
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int check_reserved(unsigned gpio, const char *func)
|
||
|
{
|
||
|
if (!get_gpio_flag(gpio, GPIOF_RESERVED)) {
|
||
|
printf("sandbox_gpio: %s: error: gpio %u not reserved\n",
|
||
|
func, gpio);
|
||
|
return -1;
|
||
|
}
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Back-channel sandbox-internal-only access to GPIO state
|
||
|
*/
|
||
|
|
||
|
int sandbox_gpio_get_value(unsigned gp)
|
||
|
{
|
||
|
if (get_gpio_flag(gp, GPIOF_OUTPUT))
|
||
|
debug("sandbox_gpio: get_value on output gpio %u\n", gp);
|
||
|
return get_gpio_flag(gp, GPIOF_HIGH);
|
||
|
}
|
||
|
|
||
|
int sandbox_gpio_set_value(unsigned gp, int value)
|
||
|
{
|
||
|
return set_gpio_flag(gp, GPIOF_HIGH, value);
|
||
|
}
|
||
|
|
||
|
int sandbox_gpio_get_direction(unsigned gp)
|
||
|
{
|
||
|
return get_gpio_flag(gp, GPIOF_OUTPUT);
|
||
|
}
|
||
|
|
||
|
int sandbox_gpio_set_direction(unsigned gp, int output)
|
||
|
{
|
||
|
return set_gpio_flag(gp, GPIOF_OUTPUT, output);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* These functions implement the public interface within U-Boot
|
||
|
*/
|
||
|
|
||
|
/* set GPIO port 'gp' as an input */
|
||
|
int gpio_direction_input(unsigned gp)
|
||
|
{
|
||
|
debug("%s: gp:%u\n", __func__, gp);
|
||
|
|
||
|
if (check_reserved(gp, __func__))
|
||
|
return -1;
|
||
|
|
||
|
return sandbox_gpio_set_direction(gp, 0);
|
||
|
}
|
||
|
|
||
|
/* set GPIO port 'gp' as an output, with polarity 'value' */
|
||
|
int gpio_direction_output(unsigned gp, int value)
|
||
|
{
|
||
|
debug("%s: gp:%u, value = %d\n", __func__, gp, value);
|
||
|
|
||
|
if (check_reserved(gp, __func__))
|
||
|
return -1;
|
||
|
|
||
|
return sandbox_gpio_set_direction(gp, 1) |
|
||
|
sandbox_gpio_set_value(gp, value);
|
||
|
}
|
||
|
|
||
|
/* read GPIO IN value of port 'gp' */
|
||
|
int gpio_get_value(unsigned gp)
|
||
|
{
|
||
|
debug("%s: gp:%u\n", __func__, gp);
|
||
|
|
||
|
if (check_reserved(gp, __func__))
|
||
|
return -1;
|
||
|
|
||
|
return sandbox_gpio_get_value(gp);
|
||
|
}
|
||
|
|
||
|
/* write GPIO OUT value to port 'gp' */
|
||
|
int gpio_set_value(unsigned gp, int value)
|
||
|
{
|
||
|
debug("%s: gp:%u, value = %d\n", __func__, gp, value);
|
||
|
|
||
|
if (check_reserved(gp, __func__))
|
||
|
return -1;
|
||
|
|
||
|
if (!sandbox_gpio_get_direction(gp)) {
|
||
|
printf("sandbox_gpio: error: set_value on input gpio %u\n", gp);
|
||
|
return -1;
|
||
|
}
|
||
|
|
||
|
return sandbox_gpio_set_value(gp, value);
|
||
|
}
|
||
|
|
||
|
int gpio_request(unsigned gp, const char *label)
|
||
|
{
|
||
|
debug("%s: gp:%u, label:%s\n", __func__, gp, label);
|
||
|
|
||
|
if (gp >= ARRAY_SIZE(state)) {
|
||
|
printf("sandbox_gpio: error: invalid gpio %u\n", gp);
|
||
|
return -1;
|
||
|
}
|
||
|
|
||
|
if (get_gpio_flag(gp, GPIOF_RESERVED)) {
|
||
|
printf("sandbox_gpio: error: gpio %u already reserved\n", gp);
|
||
|
return -1;
|
||
|
}
|
||
|
|
||
|
state[gp].label = label;
|
||
|
return set_gpio_flag(gp, GPIOF_RESERVED, 1);
|
||
|
}
|
||
|
|
||
|
int gpio_free(unsigned gp)
|
||
|
{
|
||
|
debug("%s: gp:%u\n", __func__, gp);
|
||
|
|
||
|
if (check_reserved(gp, __func__))
|
||
|
return -1;
|
||
|
|
||
|
state[gp].label = NULL;
|
||
|
return set_gpio_flag(gp, GPIOF_RESERVED, 0);
|
||
|
}
|
||
|
|
||
|
/* Display GPIO information */
|
||
|
void gpio_info(void)
|
||
|
{
|
||
|
unsigned gpio;
|
||
|
|
||
|
puts("Sandbox GPIOs\n");
|
||
|
|
||
|
for (gpio = 0; gpio < ARRAY_SIZE(state); ++gpio) {
|
||
|
const char *label = state[gpio].label;
|
||
|
|
||
|
printf("%4d: %s: %d [%c] %s\n",
|
||
|
gpio,
|
||
|
sandbox_gpio_get_direction(gpio) ? "out" : " in",
|
||
|
sandbox_gpio_get_value(gpio),
|
||
|
get_gpio_flag(gpio, GPIOF_RESERVED) ? 'x' : ' ',
|
||
|
label ? label : "");
|
||
|
}
|
||
|
}
|