path: root/drivers/usb/core/sysfs.c

// SPDX-License-Identifier: GPL-2.0
/*
 * drivers/usb/core/sysfs.c
 *
 * (C) Copyright 2002 David Brownell
 * (C) Copyright 2002,2004 Greg Kroah-Hartman
 * (C) Copyright 2002,2004 IBM Corp.
 *
 * All of the sysfs file attributes for usb devices and interfaces.
 *
 * Released under the GPLv2 only.
 */


#include <linux/kernel.h>
#include <linux/kstrtox.h>
#include <linux/string.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <linux/usb/quirks.h>
#include <linux/of.h>
#include "usb.h"

/* Active configuration fields */
#define usb_actconfig_show(field, format_string)			\
static ssize_t field##_show(struct device *dev,				\
			    struct device_attribute *attr, char *buf)	\
{									\
	struct usb_device *udev;					\
	struct usb_host_config *actconfig;				\
	ssize_t rc;							\
									\
	udev = to_usb_device(dev);					\
	rc = usb_lock_device_interruptible(udev);			\
	if (rc < 0)							\
		return -EINTR;						\
	actconfig = udev->actconfig;					\
	if (actconfig)							\
		rc = sysfs_emit(buf, format_string,			\
				actconfig->desc.field);			\
	usb_unlock_device(udev);					\
	return rc;							\
}									\

#define usb_actconfig_attr(field, format_string)		\
	usb_actconfig_show(field, format_string)		\
	static DEVICE_ATTR_RO(field)

usb_actconfig_attr(bNumInterfaces, "%2d\n");
usb_actconfig_attr(bmAttributes, "%2x\n");

static ssize_t bMaxPower_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct usb_device *udev;
	struct usb_host_config *actconfig;
	ssize_t rc;

	udev = to_usb_device(dev);
	rc = usb_lock_device_interruptible(udev);
	if (rc < 0)
		return -EINTR;
	actconfig = udev->actconfig;
	if (actconfig)
		rc = sysfs_emit(buf, "%dmA\n", usb_get_max_power(udev, actconfig));
	usb_unlock_device(udev);
	return rc;
}
static DEVICE_ATTR_RO(bMaxPower);

static ssize_t configuration_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct usb_device *udev;
	struct usb_host_config *actconfig;
	ssize_t rc;

	udev = to_usb_device(dev);
	rc = usb_lock_device_interruptible(udev);
	if (rc < 0)
		return -EINTR;
	actconfig = udev->actconfig;
	if (actconfig && actconfig->string)
		rc = sysfs_emit(buf, "%s\n", actconfig->string);
	usb_unlock_device(udev);
	return rc;
}
static DEVICE_ATTR_RO(configuration);

/* configuration value is always present, and r/w */
usb_actconfig_show(bConfigurationValue, "%u\n");

static ssize_t bConfigurationValue_store(struct device *dev,
					 struct device_attribute *attr,
					 const char *buf, size_t count)
{
	struct usb_device	*udev = to_usb_device(dev);