u-boot/drivers/reboot-mode/reboot-mode-gpio.c
Nandor Han f9db2f16cb reboot-mode: read the boot mode from GPIOs status
A use case for controlling the boot mode is when the user wants
to control the device boot by pushing a button without needing to
go in user-space.

Add a new backed for reboot mode where GPIOs are used to control the
reboot-mode. The driver is able to scan a predefined list of GPIOs
and return the magic value. Having the modes associated with
the magic value generated based on the GPIO values, allows the
reboot mode uclass to select the proper mode.

Signed-off-by: Nandor Han <nandor.han@vaisala.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2021-07-23 10:16:39 -04:00

129 lines
2.6 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c), Vaisala Oyj
*/
#include <common.h>
#include <asm/gpio.h>
#include <dm.h>
#include <dm/devres.h>
#include <errno.h>
#include <reboot-mode/reboot-mode-gpio.h>
#include <reboot-mode/reboot-mode.h>
DECLARE_GLOBAL_DATA_PTR;
static int reboot_mode_get(struct udevice *dev, u32 *buf)
{
int ret;
struct reboot_mode_gpio_platdata *plat_data;
if (!buf)
return -EINVAL;
plat_data = dev_get_plat(dev);
if (!plat_data)
return -EINVAL;
ret = dm_gpio_get_values_as_int(plat_data->gpio_desc,
plat_data->gpio_count);
if (ret < 0)
return ret;
*buf = ret;
return 0;
}
static int reboot_mode_probe(struct udevice *dev)
{
struct reboot_mode_gpio_platdata *plat_data;
plat_data = dev_get_plat(dev);
if (!plat_data)
return -EINVAL;
int ret;
#if CONFIG_IS_ENABLED(OF_CONTROL)
ret = gpio_get_list_count(dev, "gpios");
if (ret < 0)
return ret;
plat_data->gpio_count = ret;
#endif
if (plat_data->gpio_count <= 0)
return -EINVAL;
plat_data->gpio_desc = devm_kcalloc(dev, plat_data->gpio_count,
sizeof(struct gpio_desc), 0);
if (!plat_data->gpio_desc)
return -ENOMEM;
#if CONFIG_IS_ENABLED(OF_CONTROL)
ret = gpio_request_list_by_name(dev, "gpios", plat_data->gpio_desc,
plat_data->gpio_count, GPIOD_IS_IN);
if (ret < 0)
return ret;
#else
for (int i = 0; i < plat_data->gpio_count; i++) {
struct reboot_mode_gpio_config *gpio =
plat_data->gpios_config + i;
struct gpio_desc *desc = plat_data->gpio_desc + i;
ret = uclass_get_device_by_seq(UCLASS_GPIO,
gpio->gpio_dev_offset,
&desc->dev);
if (ret < 0)
return ret;
desc->flags = gpio->flags;
desc->offset = gpio->gpio_offset;
ret = dm_gpio_request(desc, "");
if (ret < 0)
return ret;
ret = dm_gpio_set_dir(desc);
if (ret < 0)
return ret;
}
#endif
return 0;
}
static int reboot_mode_remove(struct udevice *dev)
{
struct reboot_mode_gpio_platdata *plat_data;
plat_data = dev_get_plat(dev);
if (!plat_data)
return -EINVAL;
return gpio_free_list(dev, plat_data->gpio_desc, plat_data->gpio_count);
}
#if CONFIG_IS_ENABLED(OF_CONTROL)
static const struct udevice_id reboot_mode_ids[] = {
{ .compatible = "reboot-mode-gpio", 0 },
{ }
};
#endif
static const struct reboot_mode_ops reboot_mode_gpio_ops = {
.get = reboot_mode_get,
};
U_BOOT_DRIVER(reboot_mode_gpio) = {
.name = "reboot-mode-gpio",
.id = UCLASS_REBOOT_MODE,
.probe = reboot_mode_probe,
.remove = reboot_mode_remove,
#if CONFIG_IS_ENABLED(OF_CONTROL)
.of_match = reboot_mode_ids,
#endif
.plat_auto = sizeof(struct reboot_mode_gpio_platdata),
.ops = &reboot_mode_gpio_ops,
};