/* * 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, };