1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
52 lines
1.3 KiB
C
52 lines
1.3 KiB
C
/*
|
|
* 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,
|
|
};
|