mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-27 15:12:21 +00:00
486b973ee9
Add a simple driver which allows use of buttons attached to GPIOs. Reviewed-by: Simon Glass <sjg@chromium.org> Signed-off-by: Philippe Reynes <philippe.reynes@softathome.com>
112 lines
2.4 KiB
C
112 lines
2.4 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Copyright (C) 2020 Philippe Reynes <philippe.reynes@softathome.com>
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <button.h>
|
|
#include <dm.h>
|
|
#include <dm/lists.h>
|
|
#include <dm/uclass-internal.h>
|
|
#include <log.h>
|
|
#include <asm/gpio.h>
|
|
|
|
struct button_gpio_priv {
|
|
struct gpio_desc gpio;
|
|
};
|
|
|
|
static enum button_state_t button_gpio_get_state(struct udevice *dev)
|
|
{
|
|
struct button_gpio_priv *priv = dev_get_priv(dev);
|
|
int ret;
|
|
|
|
if (!dm_gpio_is_valid(&priv->gpio))
|
|
return -EREMOTEIO;
|
|
ret = dm_gpio_get_value(&priv->gpio);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
return ret ? BUTTON_ON : BUTTON_OFF;
|
|
}
|
|
|
|
static int button_gpio_probe(struct udevice *dev)
|
|
{
|
|
struct button_uc_plat *uc_plat = dev_get_uclass_platdata(dev);
|
|
struct button_gpio_priv *priv = dev_get_priv(dev);
|
|
int ret;
|
|
|
|
/* Ignore the top-level button node */
|
|
if (!uc_plat->label)
|
|
return 0;
|
|
|
|
ret = gpio_request_by_name(dev, "gpios", 0, &priv->gpio, GPIOD_IS_IN);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int button_gpio_remove(struct udevice *dev)
|
|
{
|
|
/*
|
|
* The GPIO driver may have already been removed. We will need to
|
|
* address this more generally.
|
|
*/
|
|
if (!IS_ENABLED(CONFIG_SANDBOX)) {
|
|
struct button_gpio_priv *priv = dev_get_priv(dev);
|
|
|
|
if (dm_gpio_is_valid(&priv->gpio))
|
|
dm_gpio_free(dev, &priv->gpio);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int button_gpio_bind(struct udevice *parent)
|
|
{
|
|
struct udevice *dev;
|
|
ofnode node;
|
|
int ret;
|
|
|
|
dev_for_each_subnode(node, parent) {
|
|
struct button_uc_plat *uc_plat;
|
|
const char *label;
|
|
|
|
label = ofnode_read_string(node, "label");
|
|
if (!label) {
|
|
debug("%s: node %s has no label\n", __func__,
|
|
ofnode_get_name(node));
|
|
return -EINVAL;
|
|
}
|
|
ret = device_bind_driver_to_node(parent, "button_gpio",
|
|
ofnode_get_name(node),
|
|
node, &dev);
|
|
if (ret)
|
|
return ret;
|
|
uc_plat = dev_get_uclass_platdata(dev);
|
|
uc_plat->label = label;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct button_ops button_gpio_ops = {
|
|
.get_state = button_gpio_get_state,
|
|
};
|
|
|
|
static const struct udevice_id button_gpio_ids[] = {
|
|
{ .compatible = "gpio-keys" },
|
|
{ .compatible = "gpio-keys-polled" },
|
|
{ }
|
|
};
|
|
|
|
U_BOOT_DRIVER(button_gpio) = {
|
|
.name = "button_gpio",
|
|
.id = UCLASS_BUTTON,
|
|
.of_match = button_gpio_ids,
|
|
.ops = &button_gpio_ops,
|
|
.priv_auto_alloc_size = sizeof(struct button_gpio_priv),
|
|
.bind = button_gpio_bind,
|
|
.probe = button_gpio_probe,
|
|
.remove = button_gpio_remove,
|
|
};
|