// 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);
int config, value, rc;
if (sscanf(buf, "%d", &config) != 1 || config < -1 || config > 255)
return -EINVAL;
rc = usb_lock_device_interruptible(udev);
if (rc < 0)
return -EINTR;
value = usb_set_configuration(udev, config);
usb_unlock_device(udev);
return (value < 0) ? value : count;
}
static DEVICE_ATTR_IGNORE_LOCKDEP(bConfigurationValue, S_IRUGO | S_IWUSR,
bConfigurationValue_show, bConfigurationValue_store);
#ifdef CONFIG_OF
static ssize_t devspec_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct device_node *of_node = dev->of_node;
return sysfs_emit(buf, "%pOF\n", of_node);
}
static DEVICE_ATTR_RO(devspec);
#endif
/* String fields */
#define usb_string_attr(name) \
static ssize_t name##_show(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct usb_device *udev; \
int retval; \
\
udev = to_usb_device(dev); \
retval = usb_lock_device_interruptible(udev); \
if (retval < 0) \
return -EINTR; \
retval = sysfs_emit(buf, "%s\n", udev->name); \
usb_unlock_device(udev); \
return retval; \
} \
static DEVICE_ATTR_RO(name)
usb_string_attr(product);
usb_string_attr(manufacturer);
usb_string_attr(serial);
static ssize_t speed_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
char *speed;
udev = to_usb_device(dev);
switch (udev->speed) {
case USB_SPEED_LOW:
speed = "1.5";
break;
case USB_SPEED_UNKNOWN:
case USB_SPEED_FULL:
speed = "12";
break;
case USB_SPEED_HIGH:
speed = "480";
break;
case USB_SPEED_SUPER:
speed = "5000";
break;
case USB_SPEED_SUPER_PLUS:
if (udev->ssp_rate == USB_SSP_GEN_2x2)
speed = "20000";
else
speed = "10000";
break;
default:
speed = "unknown";
}
return sysfs_emit(buf, "%s\n", speed);
}
static DEVICE_ATTR_RO(speed);
static ssize_t rx_lanes_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sysfs_emit(buf, "%d\n", udev->rx_lanes);
}
static DEVICE_ATTR_RO(rx_lanes);
static ssize_t tx_lanes_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sysfs_emit(buf, "%d\n", udev->tx_lanes);
}
static DEVICE_ATTR_RO(tx_lanes);
static ssize_t busnum_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sysfs_emit(buf, "%d\n", udev->bus->busnum);
}
static DEVICE_ATTR_RO(busnum);
static ssize_t devnum_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sysfs_emit(buf, "%d\n", udev->devnum);
}
static DEVICE_ATTR_RO(devnum);
static ssize_t devpath_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sysfs_emit(buf, "%s\n", udev->devpath);
}
static DEVICE_ATTR_RO(devpath);
static ssize_t version_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
u16 bcdUSB;
udev = to_usb_device(dev);
bcdUSB = le16_to_cpu(udev->descriptor.bcdUSB);
return sysfs_emit(buf, "%2x.%02x\n", bcdUSB >> 8, bcdUSB & 0xff);
}
static DEVICE_ATTR_RO(version);
static ssize_t maxchild_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sysfs_emit(buf, "%d\n", udev->maxchild);
}
static DEVICE_ATTR_RO(maxchild);
static ssize_t quirks_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sysfs_emit(buf, "0x%x\n", udev->quirks);
}
static DEVICE_ATTR_RO(quirks);
static ssize_t avoid_reset_quirk_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sysfs_emit(buf, "%d\n", !!(udev->quirks & USB_QUIRK_RESET));
}
static ssize_t avoid_reset_quirk_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
bool val;
int rc;
if (kstrtobool(buf, &val) != 0)
return -EINVAL;
rc = usb_lock_device_interruptible(udev);
if (rc < 0)
return -EINTR;
if (val)
udev->quirks |= USB_QUIRK_RESET;
else
udev->quirks &= ~USB_QUIRK_RESET;
usb_unlock_device(udev);
return count;
}
static DEVICE_ATTR_RW(avoid_reset_quirk);
static ssize_t urbnum_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sysfs_emit(buf, "%d\n", atomic_read(&udev->urbnum));
}
static DEVICE_ATTR_RO(urbnum);
static ssize_t ltm_capable_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
if (usb_device_supports_ltm(to_usb_device(dev)))
return sysfs_emit(buf, "%s\n", "yes");
return sysfs_emit(buf, "%s\n", "no");
}
static DEVICE_ATTR_RO(ltm_capable);
#ifdef CONFIG_PM
static ssize_t persist_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev = to_usb_device(dev);
return sysfs_emit(buf, "%d\n", udev->persist_enabled);
}
static ssize_t persist_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
bool value;
int rc;
/* Hubs are always enabled for USB_PERSIST */
if (udev->descriptor.bDeviceClass == USB_CLASS_HUB)
return -EPERM;
if (kstrtobool(buf, &value) != 0)
return -EINVAL;
rc = usb_lock_device_interruptible(udev);
if (rc < 0)
return -EINTR;
udev->persist_enabled = !!value;
usb_unlock_device(udev);
return count;
}
static DEVICE_ATTR_RW(persist);
static int add_persist_attributes(struct device *dev)
{
int rc = 0;
if (is_usb_device(dev)) {
struct usb_device *udev = to_usb_device(dev);
/* Hubs are automatically enabled for USB_PERSIST,
* no point in creating the attribute file.
*/
if (udev->descriptor.bDeviceClass != USB_CLASS_HUB)
rc = sysfs_add_file_to_group(&dev->kobj,
&dev_attr_persist.attr,
power_group_name);
}
return rc;
}
static void remove_persist_attributes(struct device *dev)
{
sysfs_remove_file_from_group(&dev->kobj,
&dev_attr_persist.attr,
power_group_name);
}
static ssize_t connected_duration_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev = to_usb_device(dev);
return sysfs_emit(buf, "%u\n",
jiffies_to_msecs(jiffies - udev->connect_time));
}
static DEVICE_ATTR_RO(connected_duration);
/*
* If the device is resumed, the last time the device was suspended has
* been pre-subtracted from active_duration. We add the current time to
* get the duration that the device was actually active.
*
* If the device is suspended, the active_duration is up-to-date.
*/
static ssize_t active_duration_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev = to_usb_device(dev);
int duration;
if (udev->state != USB_STATE_SUSPENDED)
duration = jiffies_to_msecs(jiffies + udev->active_duration);
else
duration = jiffies_to_msecs(udev->active_duration);
return sysfs_emit(buf, "%u\n", duration);
}
static DEVICE_ATTR_RO(active_duration);
static ssize_t autosuspend_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sysfs_emit(buf, "%d\n", dev->power.autosuspend_delay / 1000);
}
static ssize_t autosuspend_store(struct device *dev,
struct device_attribute *attr, const char *buf,
size_t count)
{
int value;
if (sscanf(buf, "%d", &value) != 1 || value >= INT_MAX/1000 ||
value <= -INT_MAX/1000)
return -EINVAL;
pm_runtime_set_autosuspend_delay(dev, value * 1000);
return count;
}
static DEVICE_ATTR_RW(autosuspend);
static const char on_string[] = "on";
static const char auto_string[] = "auto";
static void warn_level(void)
{
static int level_warned;
if (!level_warned) {
level_warned = 1;
printk(KERN_WARNING "WARNING! power/level is deprecated; "
"use power/control instead\n");
}
}
static ssize_t level_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev = to_usb_device(dev);
const char *p = auto_string;
warn_level();
if (udev->state != USB_STATE_SUSPENDED && !udev->dev.power.runtime_auto)
p = on_string;
return sysfs_emit(buf, "%s\n", p);
}
static ssize_t level_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
int len = count;
char *cp;
int rc = count;
int rv;
warn_level();
cp = memchr(buf, '\n', count);
if (cp)
len = cp - buf;
rv = usb_lock_device_interruptible(udev);
if (rv < 0)
return -EINTR;
if (len == sizeof on_string - 1 &&
strncmp(buf, on_string, len) == 0)
usb_disable_autosuspend(udev);
else if (len == sizeof auto_string - 1 &&
strncmp(buf, auto_string, len) == 0)
usb_enable_autosuspend(udev);
else
rc = -EINVAL;
usb_unlock_device(udev);
return rc;
}
static DEVICE_ATTR_RW(level);
static ssize_t usb2_hardware_lpm_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev = to_usb_device(dev);
const char *p;
if (udev->usb2_hw_lpm_allowed == 1)
p = "enabled";
else
p = "disabled";
return sysfs_emit(buf, "%s\n", p);
}
static ssize_t usb2_hardware_lpm_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
bool value;
int ret;
ret = usb_lock_device_interruptible(udev);
if (ret < 0)
return -EINTR;
ret = kstrtobool(buf, &value);
if (!ret) {
udev->usb2_hw_lpm_allowed = value;
if (value)
ret = usb_enable_usb2_hardware_lpm(udev);
else
ret = usb_disable_usb2_hardware_lpm(udev);
}
usb_unlock_device(udev);
if (!ret)
return count;
return ret;
}
static DEVICE_ATTR_RW(usb2_hardware_lpm);
static ssize_t usb2_lpm_l1_timeout_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct usb_device *udev = to_usb_device(dev);
return sysfs_emit(buf, "%d\n", udev->l1_params.timeout);
}
static ssize_t usb2_lpm_l1_timeout_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
u16 timeout;
if (kstrtou16(buf, 0, &timeout))
return -EINVAL;
udev->l1_params.timeout = timeout;
return count;
}
static DEVICE_ATTR_RW(usb2_lpm_l1_timeout);
static ssize_t usb2_lpm_besl_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev = to_usb_device(dev);
return sysfs_emit(buf, "%d\n", udev->l1_params.besl);
}
static ssize_t usb2_lpm_besl_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
u8 besl;
if (kstrtou8(buf, 0, &besl) || besl > 15)
return -EINVAL;
udev->l1_params.besl = besl;
return count;
}
static DEVICE_ATTR_RW(usb2_lpm_besl);
static ssize_t usb3_hardware_lpm_u1_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev = to_usb_device(dev);
const char *p;
int rc;
rc = usb_lock_device_interruptible(udev);
if (rc < 0)
return -EINTR;
if (udev->usb3_lpm_u1_enabled)
p = "enabled";
else
p = "disabled";
usb_unlock_device(udev);
return sysfs_emit(buf, "%s\n", p);
}
static DEVICE_ATTR_RO(usb3_hardware_lpm_u1);
static ssize_t usb3_hardware_lpm_u2_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev = to_usb_device(dev);
const char *p;
int rc;
rc = usb_lock_device_interruptible(udev);
if (rc < 0)
return -EINTR;
if (udev->usb3_lpm_u2_enabled)
p = "enabled";
else
p = "disabled";
usb_unlock_device(udev);
return sysfs_emit(buf, "%s\n", p);
}
static DEVICE_ATTR_RO(usb3_hardware_lpm_u2);
static struct attribute *usb2_hardware_lpm_attr[] = {
&dev_attr_usb2_hardware_lpm.attr,
&dev_attr_usb2_lpm_l1_timeout.attr,
&dev_attr_usb2_lpm_besl.attr,
NULL,
};
static const struct attribute_group usb2_hardware_lpm_attr_group = {
.name = power_group_name,
.attrs = usb2_hardware_lpm_attr,
};
static struct attribute *usb3_hardware_lpm_attr[] = {
&dev_attr_usb3_hardware_lpm_u1.attr,
&dev_attr_usb3_hardware_lpm_u2.attr,
NULL,
};
static const struct attribute_group usb3_hardware_lpm_attr_group = {
.name = power_group_name,
.attrs = usb3_hardware_lpm_attr,
};
static struct attribute *power_attrs[] = {
&dev_attr_autosuspend.attr,
&dev_attr_level.attr,
&dev_attr_connected_duration.attr,
&dev_attr_active_duration.attr,
NULL,
};
static const struct attribute_group power_attr_group = {
.name = power_group_name,
.attrs = power_attrs,
};
static int add_power_attributes(struct device *dev)
{
int rc = 0;
if (is_usb_device(dev)) {
struct usb_device *udev = to_usb_device(dev);
rc = sysfs_merge_group(&dev->kobj, &power_attr_group);
if (udev->usb2_hw_lpm_capable == 1)
rc = sysfs_merge_group(&dev->kobj,
&usb2_hardware_lpm_attr_group);
if ((udev->speed == USB_SPEED_SUPER ||
udev->speed == USB_SPEED_SUPER_PLUS) &&
udev->lpm_capable == 1)
rc = sysfs_merge_group(&dev->kobj,
&usb3_hardware_lpm_attr_group);
}
return rc;
}
static void remove_power_attributes(struct device *dev)
{
sysfs_unmerge_group(&dev->kobj, &usb3_hardware_lpm_attr_group);
sysfs_unmerge_group(&dev->kobj, &usb2_hardware_lpm_attr_group);
sysfs_unmerge_group(&dev->kobj, &power_attr_group);
}
#else
#define add_persist_attributes(dev) 0
#define remove_persist_attributes(dev) do {} while (0)
#define add_power_attributes(dev) 0
#define remove_power_attributes(dev) do {} while (0)
#endif /* CONFIG_PM */
/* Descriptor fields */
#define usb_descriptor_attr_le16(field, format_string) \
static ssize_t \
field##_show(struct device *dev, struct device_attribute *attr, \
char *buf) \
{ \
struct usb_device *udev; \
\
udev = to_usb_device(dev); \
return sysfs_emit(buf, format_string, \
le16_to_cpu(udev->descriptor.field)); \
} \
static DEVICE_ATTR_RO(field)
usb_descriptor_attr_le16(idVendor, "%04x\n");
usb_descriptor_attr_le16(idProduct, "%04x\n");
usb_descriptor_attr_le16(bcdDevice, "%04x\n");
#define usb_descriptor_attr(field, format_string) \
static ssize_t \
field##_show(struct device *dev, struct device_attribute *attr, \
char *buf) \
{ \
struct usb_device *udev; \
\
udev = to_usb_device(dev); \
return sysfs_emit(buf, format_string, udev->descriptor.field); \
} \
static DEVICE_ATTR_RO(field)
usb_descriptor_attr(bDeviceClass, "%02x\n");
usb_descriptor_attr(bDeviceSubClass, "%02x\n");
usb_descriptor_attr(bDeviceProtocol, "%02x\n");
usb_descriptor_attr(bNumConfigurations, "%d\n");
usb_descriptor_attr(bMaxPacketSize0, "%d\n");
/* show if the device is authorized (1) or not (0) */
static ssize_t authorized_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *usb_dev = to_usb_device(dev);
return sysfs_emit(buf, "%u\n", usb_dev->authorized);
}
/*
* Authorize a device to be used in the system
*
* Writing a 0 deauthorizes the device, writing a 1 authorizes it.
*/
static ssize_t authorized_store(struct device *dev,
struct device_attribute *attr, const char *buf,
size_t size)
{
ssize_t result;
struct usb_device *usb_dev = to_usb_device(dev);
bool val;
if (kstrtobool(buf, &val) != 0)
result = -EINVAL;
else if (val)
result = usb_authorize_device(usb_dev);
else
result = usb_deauthorize_device(usb_dev);
return result < 0 ? result : size;
}
static DEVICE_ATTR_IGNORE_LOCKDEP(authorized, S_IRUGO | S_IWUSR,
authorized_show, authorized_store);
/* "Safely remove a device" */
static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
int rc = 0;
usb_lock_device(udev);
if (udev->state != USB_STATE_NOTATTACHED) {
/* To avoid races, first unconfigure and then remove */
usb_set_configuration(udev, -1);
rc = usb_remove_device(udev);
}
if (rc == 0)
rc = count;
usb_unlock_device(udev);
return rc;
}
static DEVICE_ATTR_IGNORE_LOCKDEP(remove, S_IWUSR, NULL, remove_store);
static struct attribute *dev_attrs[] = {
/* current configuration's attributes */
&dev_attr_configuration.attr,
&dev_attr_bNumInterfaces.attr,
&dev_attr_bConfigurationValue.attr,
&dev_attr_bmAttributes.attr,
&dev_attr_bMaxPower.attr,
/* device attributes */
&dev_attr_urbnum.attr,
&dev_attr_idVendor.attr,
&dev_attr_idProduct.attr,
&dev_attr_bcdDevice.attr,
&dev_attr_bDeviceClass.attr,
&dev_attr_bDeviceSubClass.attr,
&dev_attr_bDeviceProtocol.attr,
&dev_attr_bNumConfigurations.attr,
&dev_attr_bMaxPacketSize0.attr,
&dev_attr_speed.attr,
&dev_attr_rx_lanes.attr,
&dev_attr_tx_lanes.attr,
&dev_attr_busnum.attr,
&dev_attr_devnum.attr,
&dev_attr_devpath.attr,
&dev_attr_version.attr,
&dev_attr_maxchild.attr,
&dev_attr_quirks.attr,
&dev_attr_avoid_reset_quirk.attr,
&dev_attr_authorized.attr,
&dev_attr_remove.attr,
&dev_attr_ltm_capable.attr,
#ifdef CONFIG_OF
&dev_attr_devspec.attr,
#endif
NULL,
};
static const struct attribute_group dev_attr_grp = {
.attrs = dev_attrs,
};
/* When modifying this list, be sure to modify dev_string_attrs_are_visible()
* accordingly.
*/
static struct attribute *dev_string_attrs[] = {
&dev_attr_manufacturer.attr,
&dev_attr_product.attr,
&dev_attr_serial.attr,
NULL
};
static umode_t dev_string_attrs_are_visible(struct kobject *kobj,
struct attribute *a, int n)
{
struct device *dev = kobj_to_dev(kobj);
struct usb_device *udev = to_usb_device(dev);
if (a == &dev_attr_manufacturer.attr) {
if (udev->manufacturer == NULL)
return 0;
} else if (a == &dev_attr_product.attr) {
if (udev->product == NULL)
return 0;
} else if (a == &dev_attr_serial.attr) {
if (udev->serial == NULL)
return 0;
}
return a->mode;
}
static const struct attribute_group dev_string_attr_grp = {
.attrs = dev_string_attrs,
.is_visible = dev_string_attrs_are_visible,
};
/* Binary descriptors */
static ssize_t
descriptors_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr,
char *buf, loff_t off, size_t count)
{
struct device *dev = kobj_to_dev(kobj);
struct usb_device *udev = to_usb_device(dev);
size_t nleft = count;
size_t srclen, n;
int cfgno;
void *src;
/* The binary attribute begins with the device descriptor.
* Following that are the raw descriptor entries for all the
* configurations (config plus subsidiary descriptors).
*/
for (cfgno = -1; cfgno < udev->descriptor.bNumConfigurations &&
nleft > 0; ++cfgno) {
if (cfgno < 0) {
src = &udev->descriptor;
srclen = sizeof(struct usb_device_descriptor);
} else {
src = udev->rawdescriptors[cfgno];
srclen = le16_to_cpu(udev->config[cfgno].desc.
wTotalLength);
}
if (off < srclen) {
n = min(nleft, srclen - (size_t) off);
memcpy(buf, src + off, n);
nleft -= n;
buf += n;
off = 0;
} else {
off -= srclen;
}
}
return count - nleft;
}
static BIN_ATTR_RO(descriptors, 18 + 65535); /* dev descr + max-size raw descriptor */
static ssize_t
bos_descriptors_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr,
char *buf, loff_t off, size_t count)
{
struct device *dev = kobj_to_dev(kobj);
struct usb_device *udev = to_usb_device(dev);
struct usb_host_bos *bos = udev->bos;
struct usb_bos_descriptor *desc;
size_t desclen, n = 0;
if (bos) {
desc = bos->desc;
desclen = le16_to_cpu(desc->wTotalLength);
if (off < desclen) {
n = min(count, desclen - (size_t) off);
memcpy(buf, (void *) desc + off, n);
}
}
return n;
}
static BIN_ATTR_RO(bos_descriptors, 65535); /* max-size BOS */
/* When modifying this list, be sure to modify dev_bin_attrs_are_visible()
* accordingly.
*/
static struct bin_attribute *dev_bin_attrs[] = {
&bin_attr_descriptors,
&bin_attr_bos_descriptors,
NULL
};
static umode_t dev_bin_attrs_are_visible(struct kobject *kobj,
struct bin_attribute *a, int n)
{
struct device *dev = kobj_to_dev(kobj);
struct usb_device *udev = to_usb_device(dev);
/*
* There's no need to check if the descriptors attribute should
* be visible because all devices have a device descriptor. The
* bos_descriptors attribute should be visible if and only if
* the device has a BOS, so check if it exists here.
*/
if (a == &bin_attr_bos_descriptors) {
if (udev->bos == NULL)
return 0;
}
return a->attr.mode;
}
static const struct attribute_group dev_bin_attr_grp = {
.bin_attrs = dev_bin_attrs,
.is_bin_visible = dev_bin_attrs_are_visible,
};
const struct attribute_group *usb_device_groups[] = {
&dev_attr_grp,
&dev_string_attr_grp,
&dev_bin_attr_grp,
NULL
};
/*
* Show & store the current value of authorized_default
*/
static ssize_t authorized_default_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *rh_usb_dev = to_usb_device(dev);
struct usb_bus *usb_bus = rh_usb_dev->bus;
struct usb_hcd *hcd;
hcd = bus_to_hcd(usb_bus);
return sysfs_emit(buf, "%u\n", hcd->dev_policy);
}
static ssize_t authorized_default_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t size)
{
ssize_t result;
unsigned int val;
struct usb_device *rh_usb_dev = to_usb_device(dev);
struct usb_bus *usb_bus = rh_usb_dev->bus;
struct usb_hcd *hcd;
hcd = bus_to_hcd(usb_bus);
result = sscanf(buf, "%u\n", &val);
if (result == 1) {
hcd->dev_policy = val <= USB_DEVICE_AUTHORIZE_INTERNAL ?
val : USB_DEVICE_AUTHORIZE_ALL;
result = size;
} else {
result = -EINVAL;
}
return result;
}
static DEVICE_ATTR_RW(authorized_default);
/*
* interface_authorized_default_show - show default authorization status
* for USB interfaces
*
* note: interface_authorized_default is the default value
* for initializing the authorized attribute of interfaces
*/
static ssize_t interface_authorized_default_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *usb_dev = to_usb_device(dev);
struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
return sysfs_emit(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd));
}
/*
* interface_authorized_default_store - store default authorization status
* for USB interfaces
*
* note: interface_authorized_default is the default value
* for initializing the authorized attribute of interfaces
*/
static ssize_t interface_authorized_default_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct usb_device *usb_dev = to_usb_device(dev);
struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
int rc = count;
bool val;
if (kstrtobool(buf, &val) != 0)
return -EINVAL;
if (val)
set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
else
clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
return rc;
}
static DEVICE_ATTR_RW(interface_authorized_default);
/* Group all the USB bus attributes */
static struct attribute *usb_bus_attrs[] = {
&dev_attr_authorized_default.attr,
&dev_attr_interface_authorized_default.attr,
NULL,
};
static const struct attribute_group usb_bus_attr_group = {
.name = NULL, /* we want them in the same directory */
.attrs = usb_bus_attrs,
};
static int add_default_authorized_attributes(struct device *dev)
{
int rc = 0;
if (is_usb_device(dev))
rc = sysfs_create_group(&dev->kobj, &usb_bus_attr_group);
return rc;
}
static void remove_default_authorized_attributes(struct device *dev)
{
if (is_usb_device(dev)) {
sysfs_remove_group(&dev->kobj, &usb_bus_attr_group);
}
}
int usb_create_sysfs_dev_files(struct usb_device *udev)
{
struct device *dev = &udev->dev;
int retval;
retval = add_persist_attributes(dev);
if (retval)
goto error;
retval = add_power_attributes(dev);
if (retval)
goto error;
if (is_root_hub(udev)) {
retval = add_default_authorized_attributes(dev);
if (retval)
goto error;
}
return retval;
error:
usb_remove_sysfs_dev_files(udev);
return retval;
}
void usb_remove_sysfs_dev_files(struct usb_device *udev)
{
struct device *dev = &udev->dev;
if (is_root_hub(udev))
remove_default_authorized_attributes(dev);
remove_power_attributes(dev);
remove_persist_attributes(dev);
}
/* Interface Association Descriptor fields */
#define usb_intf_assoc_attr(field, format_string) \
static ssize_t \
iad_##field##_show(struct device *dev, struct device_attribute *attr, \
char *buf) \
{ \
struct usb_interface *intf = to_usb_interface(dev); \
\
return sysfs_emit(buf, format_string, \
intf->intf_assoc->field); \
} \
static DEVICE_ATTR_RO(iad_##field)
usb_intf_assoc_attr(bFirstInterface, "%02x\n");
usb_intf_assoc_attr(bInterfaceCount, "%02d\n");
usb_intf_assoc_attr(bFunctionClass, "%02x\n");
usb_intf_assoc_attr(bFunctionSubClass, "%02x\n");
usb_intf_assoc_attr(bFunctionProtocol, "%02x\n");
/* Interface fields */
#define usb_intf_attr(field, format_string) \
static ssize_t \
field##_show(struct device *dev, struct device_attribute *attr, \
char *buf) \
{ \
struct usb_interface *intf = to_usb_interface(dev); \
\
return sysfs_emit(buf, format_string, \
intf->cur_altsetting->desc.field); \
} \
static DEVICE_ATTR_RO(field)
usb_intf_attr(bInterfaceNumber, "%02x\n");
usb_intf_attr(bAlternateSetting, "%2d\n");
usb_intf_attr(bNumEndpoints, "%02x\n");
usb_intf_attr(bInterfaceClass, "%02x\n");
usb_intf_attr(bInterfaceSubClass, "%02x\n");
usb_intf_attr(bInterfaceProtocol, "%02x\n");
static ssize_t interface_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_interface *intf;
char *string;
intf = to_usb_interface(dev);
string = READ_ONCE(intf->cur_altsetting->string);
if (!string)
return 0;
return sysfs_emit(buf, "%s\n", string);
}
static DEVICE_ATTR_RO(interface);
static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_interface *intf;
struct usb_device *udev;
struct usb_host_interface *alt;
intf = to_usb_interface(dev);
udev = interface_to_usbdev(intf);
alt = READ_ONCE(intf->cur_altsetting);
return sysfs_emit(buf,
"usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02X"
"ic%02Xisc%02Xip%02Xin%02X\n",
le16_to_cpu(udev->descriptor.idVendor),
le16_to_cpu(udev->descriptor.idProduct),
le16_to_cpu(udev->descriptor.bcdDevice),
udev->descriptor.bDeviceClass,
udev->descriptor.bDeviceSubClass,
udev->descriptor.bDeviceProtocol,
alt->desc.bInterfaceClass,
alt->desc.bInterfaceSubClass,
alt->desc.bInterfaceProtocol,
alt->desc.bInterfaceNumber);
}
static DEVICE_ATTR_RO(modalias);
static ssize_t supports_autosuspend_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
int s;
s = device_lock_interruptible(dev);
if (s < 0)
return -EINTR;
/* Devices will be autosuspended even when an interface isn't claimed */
s = (!dev->driver || to_usb_driver(dev->driver)->supports_autosuspend);
device_unlock(dev);
return sysfs_emit(buf, "%u\n", s);
}
static DEVICE_ATTR_RO(supports_autosuspend);
/*
* interface_authorized_show - show authorization status of an USB interface
* 1 is authorized, 0 is deauthorized
*/
static ssize_t interface_authorized_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_interface *intf = to_usb_interface(dev);
return sysfs_emit(buf, "%u\n", intf->authorized);
}
/*
* interface_authorized_store - authorize or deauthorize an USB interface
*/
static ssize_t interface_authorized_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct usb_interface *intf = to_usb_interface(dev);
bool val;
struct kernfs_node *kn;
if (kstrtobool(buf, &val) != 0)
return -EINVAL;
if (val) {
usb_authorize_interface(intf);
} else {
/*
* Prevent deadlock if another process is concurrently
* trying to unregister intf.
*/
kn = sysfs_break_active_protection(&dev->kobj, &attr->attr);
if (kn) {
usb_deauthorize_interface(intf);
sysfs_unbreak_active_protection(kn);
}
}
return count;
}
static struct device_attribute dev_attr_interface_authorized =
__ATTR(authorized, S_IRUGO | S_IWUSR,
interface_authorized_show, interface_authorized_store);
static struct attribute *intf_attrs[] = {
&dev_attr_bInterfaceNumber.attr,
&dev_attr_bAlternateSetting.attr,
&dev_attr_bNumEndpoints.attr,
&dev_attr_bInterfaceClass.attr,
&dev_attr_bInterfaceSubClass.attr,
&dev_attr_bInterfaceProtocol.attr,
&dev_attr_modalias.attr,
&dev_attr_supports_autosuspend.attr,
&dev_attr_interface_authorized.attr,
NULL,
};
static const struct attribute_group intf_attr_grp = {
.attrs = intf_attrs,
};
static struct attribute *intf_assoc_attrs[] = {
&dev_attr_iad_bFirstInterface.attr,
&dev_attr_iad_bInterfaceCount.attr,
&dev_attr_iad_bFunctionClass.attr,
&dev_attr_iad_bFunctionSubClass.attr,
&dev_attr_iad_bFunctionProtocol.attr,
NULL,
};
static umode_t intf_assoc_attrs_are_visible(struct kobject *kobj,
struct attribute *a, int n)
{
struct device *dev = kobj_to_dev(kobj);
struct usb_interface *intf = to_usb_interface(dev);
if (intf->intf_assoc == NULL)
return 0;
return a->mode;
}
static const struct attribute_group intf_assoc_attr_grp = {
.attrs = intf_assoc_attrs,
.is_visible = intf_assoc_attrs_are_visible,
};
static ssize_t wireless_status_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_interface *intf;
intf = to_usb_interface(dev);
if (intf->wireless_status == USB_WIRELESS_STATUS_DISCONNECTED)
return sysfs_emit(buf, "%s\n", "disconnected");
return sysfs_emit(buf, "%s\n", "connected");
}
static DEVICE_ATTR_RO(wireless_status);
static struct attribute *intf_wireless_status_attrs[] = {
&dev_attr_wireless_status.attr,
NULL
};
static umode_t intf_wireless_status_attr_is_visible(struct kobject *kobj,
struct attribute *a, int n)
{
struct device *dev = kobj_to_dev(kobj);
struct usb_interface *intf = to_usb_interface(dev);
if (a != &dev_attr_wireless_status.attr ||
intf->wireless_status != USB_WIRELESS_STATUS_NA)
return a->mode;
return 0;
}
static const struct attribute_group intf_wireless_status_attr_grp = {
.attrs = intf_wireless_status_attrs,
.is_visible = intf_wireless_status_attr_is_visible,
};
int usb_update_wireless_status_attr(struct usb_interface *intf)
{
struct device *dev = &intf->dev;
int ret;
ret = sysfs_update_group(&dev->kobj, &intf_wireless_status_attr_grp);
if (ret < 0)
return ret;
sysfs_notify(&dev->kobj, NULL, "wireless_status");
kobject_uevent(&dev->kobj, KOBJ_CHANGE);
return 0;
}
const struct attribute_group *usb_interface_groups[] = {
&intf_attr_grp,
&intf_assoc_attr_grp,
&intf_wireless_status_attr_grp,
NULL
};
void usb_create_sysfs_intf_files(struct usb_interface *intf)
{
struct usb_device *udev = interface_to_usbdev(intf);
struct usb_host_interface *alt = intf->cur_altsetting;
if (intf->sysfs_files_created || intf->unregistering)
return;
if (!alt->string && !(udev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS))
alt->string = usb_cache_string(udev, alt->desc.iInterface);
if (alt->string && device_create_file(&intf->dev, &dev_attr_interface)) {
/* This is not a serious error */
dev_dbg(&intf->dev, "interface string descriptor file not created\n");
}
intf->sysfs_files_created = 1;
}
void usb_remove_sysfs_intf_files(struct usb_interface *intf)
{
if (!intf->sysfs_files_created)
return;
device_remove_file(&intf->dev, &dev_attr_interface);
intf->sysfs_files_created = 0;
}
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