diff options
Diffstat (limited to 'drivers/sysreset/poweroff_gpio.c')
-rw-r--r-- | drivers/sysreset/poweroff_gpio.c | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/drivers/sysreset/poweroff_gpio.c b/drivers/sysreset/poweroff_gpio.c new file mode 100644 index 0000000000..ac482c37f4 --- /dev/null +++ b/drivers/sysreset/poweroff_gpio.c @@ -0,0 +1,92 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Toggles a GPIO pin to power down a device + * + * Created using the Linux driver as reference, which + * has been written by: + * + * Jamie Lentin <jm@lentin.co.uk> + * Andrew Lunn <andrew@lunn.ch> + * + * Copyright (C) 2012 Jamie Lentin + */ + +#include <common.h> +#include <dm.h> +#include <errno.h> +#include <log.h> +#include <sysreset.h> + +#include <asm/gpio.h> +#include <linux/delay.h> + +struct poweroff_gpio_info { + struct gpio_desc gpio; + u32 active_delay_ms; + u32 inactive_delay_ms; + u32 timeout_ms; +}; + +static int poweroff_gpio_request(struct udevice *dev, enum sysreset_t type) +{ + struct poweroff_gpio_info *priv = dev_get_priv(dev); + int r; + + if (type != SYSRESET_POWER_OFF) + return -ENOSYS; + + debug("GPIO poweroff\n"); + + /* drive it active, also inactive->active edge */ + r = dm_gpio_set_value(&priv->gpio, 1); + if (r < 0) + return r; + mdelay(priv->active_delay_ms); + + /* drive inactive, also active->inactive edge */ + r = dm_gpio_set_value(&priv->gpio, 0); + if (r < 0) + return r; + mdelay(priv->inactive_delay_ms); + + /* drive it active, also inactive->active edge */ + r = dm_gpio_set_value(&priv->gpio, 1); + if (r < 0) + return r; + + /* give it some time */ + mdelay(priv->timeout_ms); + + return -EINPROGRESS; +} + +static int poweroff_gpio_probe(struct udevice *dev) +{ + struct poweroff_gpio_info *priv = dev_get_priv(dev); + int flags; + + flags = dev_read_bool(dev, "input") ? GPIOD_IS_IN : GPIOD_IS_OUT; + priv->active_delay_ms = dev_read_u32_default(dev, "active-delay-ms", 100); + priv->inactive_delay_ms = dev_read_u32_default(dev, "inactive-delay-ms", 100); + priv->timeout_ms = dev_read_u32_default(dev, "timeout-ms", 3000); + + return gpio_request_by_name(dev, "gpios", 0, &priv->gpio, flags); +} + +static struct sysreset_ops poweroff_gpio_ops = { + .request = poweroff_gpio_request, +}; + +static const struct udevice_id poweroff_gpio_ids[] = { + { .compatible = "gpio-poweroff", }, + {}, +}; + +U_BOOT_DRIVER(poweroff_gpio) = { + .name = "poweroff-gpio", + .id = UCLASS_SYSRESET, + .ops = &poweroff_gpio_ops, + .probe = poweroff_gpio_probe, + .priv_auto_alloc_size = sizeof(struct poweroff_gpio_info), + .of_match = poweroff_gpio_ids, +}; |