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