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/*
* drivers/base/interface.c - common driverfs interface that's exported to
* the world for all devices.
*
* Copyright (c) 2002-3 Patrick Mochel
* Copyright (c) 2002-3 Open Source Development Labs
*
* This file is released under the GPLv2
*
*/
#include <linux/device.h>
#include <linux/err.h>
#include <linux/stat.h>
#include <linux/string.h>
/**
* detach_state - control the default power state for the device.
*
* This is the state the device enters when it's driver module is
* unloaded. The value is an unsigned integer, in the range of 0-4.
* '0' indicates 'On', so no action will be taken when the driver is
* unloaded. This is the default behavior.
* '4' indicates 'Off', meaning the driver core will call the driver's
* shutdown method to quiesce the device.
* 1-3 indicate a low-power state for the device to enter via the
* driver's suspend method.
*/
static ssize_t detach_show(struct device * dev, char * buf)
{
return sprintf(buf, "%u\n", dev->detach_state);
}
static ssize_t detach_store(struct device * dev, const char * buf, size_t n)
{
u32 state;
state = simple_strtoul(buf, NULL, 10);
if (state > 4)
return -EINVAL;
dev->detach_state = state;
return n;
}
static DEVICE_ATTR(detach_state, 0644, detach_show, detach_store);
struct attribute * dev_default_attrs[] = {
&dev_attr_detach_state.attr,
NULL,
};
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