mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-08-20 00:48:52 +09:00
![Wolfgang Denk](/assets/img/avatar_default.png)
Signed-off-by: Wolfgang Denk <wd@denx.de> [trini: Fixup common/cmd_io.c] Signed-off-by: Tom Rini <trini@ti.com>
194 lines
4.0 KiB
C
194 lines
4.0 KiB
C
/*
|
|
* Copyright (c) 2011 The Chromium OS Authors.
|
|
* SPDX-License-Identifier: GPL-2.0+
|
|
*/
|
|
|
|
#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 : "");
|
|
}
|
|
}
|