2 # USB Core configuration
5 bool "USB verbose debug messages"
8 Say Y here if you want the USB core & hub drivers to produce a bunch
9 of debug messages to the system log. Select this if you are having a
10 problem with USB support and want to see more of what is going on.
12 comment "Miscellaneous USB options"
16 bool "USB device filesystem"
19 If you say Y here (and to "/proc file system support" in the "File
20 systems" section, above), you will get a file /proc/bus/usb/devices
21 which lists the devices currently connected to your USB bus or
22 busses, and for every connected device a file named
23 "/proc/bus/usb/xxx/yyy", where xxx is the bus number and yyy the
24 device number; the latter files can be used by user space programs
25 to talk directly to the device. These files are "virtual", meaning
26 they are generated on the fly and not stored on the hard drive.
28 You may need to mount the usbfs file system to see the files, use
29 mount -t usbfs none /proc/bus/usb
31 For the format of the various /proc/bus/usb/ files, please read
32 <file:Documentation/usb/proc_usb_info.txt>.
34 Usbfs files can't handle Access Control Lists (ACL), which are the
35 default way to grant access to USB devices for untrusted users of a
36 desktop system. The usbfs functionality is replaced by real
37 device-nodes managed by udev. These nodes live in /dev/bus/usb and
40 config USB_DEVICE_CLASS
41 bool "USB device class-devices (DEPRECATED)"
45 Userspace access to USB devices is granted by device-nodes exported
46 directly from the usbdev in sysfs. Old versions of the driver
47 core and udev needed additional class devices to export device nodes.
49 These additional devices are difficult to handle in userspace, if
50 information about USB interfaces must be available. One device
51 contains the device node, the other device contains the interface
52 data. Both devices are at the same level in sysfs (siblings) and one
53 can't access the other. The device node created directly by the
54 usb device is the parent device of the interface and therefore
55 easily accessible from the interface event.
57 This option provides backward compatibility for libusb device
58 nodes (lsusb) when usbfs is not used, and the following udev rule
60 SUBSYSTEM=="usb", ACTION=="add", ENV{DEVTYPE}=="usb_device", \
61 NAME="bus/usb/$env{BUSNUM}/$env{DEVNUM}", MODE="0644"
63 config USB_DYNAMIC_MINORS
64 bool "Dynamic USB minor allocation (EXPERIMENTAL)"
65 depends on USB && EXPERIMENTAL
67 If you say Y here, the USB subsystem will use dynamic minor
68 allocation for any device that uses the USB major number.
69 This means that you can have more than 16 of a single type
70 of device (like USB printers).
72 If you are unsure about this, say N here.
75 bool "USB selective suspend/resume and wakeup (EXPERIMENTAL)"
76 depends on USB && PM && EXPERIMENTAL
78 If you say Y here, you can use driver calls or the sysfs
79 "power/state" file to suspend or resume individual USB
82 Also, USB "remote wakeup" signaling is supported, whereby some
83 USB devices (like keyboards and network adapters) can wake up
84 their parent hub. That wakeup cascades up the USB tree, and
85 could wake the system from states like suspend-to-RAM.
87 If you are unsure about this, say N here.
91 depends on USB && EXPERIMENTAL
96 config USB_OTG_WHITELIST
97 bool "Rely on OTG Targeted Peripherals List"
101 If you say Y here, the "otg_whitelist.h" file will be used as a
102 product whitelist, so USB peripherals not listed there will be
103 rejected during enumeration. This behavior is required by the
104 USB OTG specification for all devices not on your product's
105 "Targeted Peripherals List".
107 Otherwise, peripherals not listed there will only generate a
108 warning and enumeration will continue. That's more like what
109 normal Linux-USB hosts do (other than the warning), and is
110 convenient for many stages of product development.
112 config USB_OTG_BLACKLIST_HUB
113 bool "Disable external hubs"
116 If you say Y here, then Linux will refuse to enumerate
117 external hubs. OTG hosts are allowed to reduce hardware
118 and software costs by not supporting external hubs.