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#include <common.h>
#include <gpio.h>
#include <errno.h>
#include <malloc.h>
static LIST_HEAD(chip_list);
struct gpio_info {
struct gpio_chip *chip;
bool requested;
char *label;
};
static struct gpio_info gpio_desc[ARCH_NR_GPIOS];
static int gpio_ensure_requested(struct gpio_info *gi, int gpio)
{
if (gi->requested)
return 0;
return gpio_request(gpio, "gpio");
}
int gpio_request(unsigned gpio, const char *label)
{
struct gpio_info *gi = &gpio_desc[gpio];
struct gpio_chip *chip = gi->chip;
int ret;
if (!gpio_is_valid(gpio))
return -EINVAL;
if (!chip)
return -EINVAL;
if (gi->requested)
return -EBUSY;
if (chip->ops->request) {
ret = chip->ops->request(chip, gpio - chip->base);
if (ret)
return ret;
}
gi->requested = true;
gi->label = xstrdup(label);
return 0;
}
void gpio_free(unsigned gpio)
{
struct gpio_info *gi = &gpio_desc[gpio];
struct gpio_chip *chip = gi->chip;
if (!gpio_is_valid(gpio))
return;
if (!chip)
return;
if (!gi->requested)
return;
if (chip->ops->free)
chip->ops->free(chip, gpio - chip->base);
gi->requested = false;
free(gi->label);
}
void gpio_set_value(unsigned gpio, int value)
{
struct gpio_info *gi = &gpio_desc[gpio];
struct gpio_chip *chip = gi->chip;
if (!gpio_is_valid(gpio))
return;
if (!chip)
return;
if (gpio_ensure_requested(gi, gpio))
return;
if (!chip->ops->set)
return;
chip->ops->set(chip, gpio - chip->base, value);
}
EXPORT_SYMBOL(gpio_set_value);
int gpio_get_value(unsigned gpio)
{
struct gpio_info *gi = &gpio_desc[gpio];
struct gpio_chip *chip = gi->chip;
int ret;
if (!gpio_is_valid(gpio))
return -EINVAL;
if (!chip)
return -ENODEV;
ret = gpio_ensure_requested(gi, gpio);
if (ret)
return ret;
if (!chip->ops->get)
return -ENOSYS;
return chip->ops->get(chip, gpio - chip->base);
}
EXPORT_SYMBOL(gpio_get_value);
int gpio_direction_output(unsigned gpio, int value)
{
struct gpio_info *gi = &gpio_desc[gpio];
struct gpio_chip *chip = gi->chip;
int ret;
if (!gpio_is_valid(gpio))
return -EINVAL;
if (!chip)
return -ENODEV;
ret = gpio_ensure_requested(gi, gpio);
if (ret)
return ret;
if (!chip->ops->direction_output)
return -ENOSYS;
return chip->ops->direction_output(chip, gpio - chip->base, value);
}
EXPORT_SYMBOL(gpio_direction_output);
int gpio_direction_input(unsigned gpio)
{
struct gpio_info *gi = &gpio_desc[gpio];
struct gpio_chip *chip = gi->chip;
int ret;
if (!gpio_is_valid(gpio))
return -EINVAL;
if (!chip)
return -ENODEV;
ret = gpio_ensure_requested(gi, gpio);
if (ret)
return ret;
if (!chip->ops->direction_input)
return -ENOSYS;
return chip->ops->direction_input(chip, gpio - chip->base);
}
EXPORT_SYMBOL(gpio_direction_input);
static int gpiochip_find_base(int start, int ngpio)
{
int i;
int spare = 0;
int base = -ENOSPC;
if (start < 0)
start = 0;
for (i = start; i < ARCH_NR_GPIOS; i++) {
struct gpio_chip *chip = gpio_desc[i].chip;
if (!chip) {
spare++;
if (spare == ngpio) {
base = i + 1 - ngpio;
break;
}
} else {
spare = 0;
i += chip->ngpio - 1;
}
}
if (gpio_is_valid(base))
debug("%s: found new base at %d\n", __func__, base);
return base;
}
int gpiochip_add(struct gpio_chip *chip)
{
int base, i;
base = gpiochip_find_base(chip->base, chip->ngpio);
if (base < 0)
return base;
if (chip->base >= 0 && chip->base != base)
return -EBUSY;
chip->base = base;
list_add_tail(&chip->list, &chip_list);
for (i = chip->base; i < chip->base + chip->ngpio; i++)
gpio_desc[i].chip = chip;
return 0;
}
int gpio_get_num(struct device_d *dev, int gpio)
{
struct gpio_chip *chip;
list_for_each_entry(chip, &chip_list, list) {
if (chip->dev == dev)
return chip->base + gpio;
}
return -ENODEV;
}
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