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 config USB_ANNOUNCE_NEW_DEVICES
13 bool "USB announce new devices"
17 Say Y here if you want the USB core to always announce the
18 idVendor, idProduct, Manufacturer, Product, and SerialNumber
19 strings for every new USB device to the syslog. This option is
20 usually used by distro vendors to help with debugging and to
21 let users know what specific device was added to the machine
24 If you do not want this kind of information sent to the system
25 log, or have any doubts about this, say N here.
27 comment "Miscellaneous USB options"
31 bool "USB device filesystem (DEPRECATED)"
34 If you say Y here (and to "/proc file system support" in the "File
35 systems" section, above), you will get a file /proc/bus/usb/devices
36 which lists the devices currently connected to your USB bus or
37 busses, and for every connected device a file named
38 "/proc/bus/usb/xxx/yyy", where xxx is the bus number and yyy the
39 device number; the latter files can be used by user space programs
40 to talk directly to the device. These files are "virtual", meaning
41 they are generated on the fly and not stored on the hard drive.
43 You may need to mount the usbfs file system to see the files, use
44 mount -t usbfs none /proc/bus/usb
46 For the format of the various /proc/bus/usb/ files, please read
47 <file:Documentation/usb/proc_usb_info.txt>.
49 Modern Linux systems do not use this.
51 Usbfs entries are files and not character devices; usbfs can't
52 handle Access Control Lists (ACL) which are the default way to
53 grant access to USB devices for untrusted users of a desktop
56 The usbfs functionality is replaced by real device-nodes managed by
57 udev. These nodes lived in /dev/bus/usb and are used by libusb.
59 config USB_DEVICE_CLASS
60 bool "USB device class-devices (DEPRECATED)"
64 Userspace access to USB devices is granted by device-nodes exported
65 directly from the usbdev in sysfs. Old versions of the driver
66 core and udev needed additional class devices to export device nodes.
68 These additional devices are difficult to handle in userspace, if
69 information about USB interfaces must be available. One device
70 contains the device node, the other device contains the interface
71 data. Both devices are at the same level in sysfs (siblings) and one
72 can't access the other. The device node created directly by the
73 usb device is the parent device of the interface and therefore
74 easily accessible from the interface event.
76 This option provides backward compatibility for libusb device
77 nodes (lsusb) when usbfs is not used, and the following udev rule
79 SUBSYSTEM=="usb", ACTION=="add", ENV{DEVTYPE}=="usb_device", \
80 NAME="bus/usb/$env{BUSNUM}/$env{DEVNUM}", MODE="0644"
82 config USB_DYNAMIC_MINORS
83 bool "Dynamic USB minor allocation"
86 If you say Y here, the USB subsystem will use dynamic minor
87 allocation for any device that uses the USB major number.
88 This means that you can have more than 16 of a single type
89 of device (like USB printers).
91 If you are unsure about this, say N here.
94 bool "USB runtime power management (suspend/resume and wakeup)"
95 depends on USB && PM_RUNTIME
97 If you say Y here, you can use driver calls or the sysfs
98 "power/level" file to suspend or resume individual USB
99 peripherals and to enable or disable autosuspend (see
100 Documentation/usb/power-management.txt for more details).
102 Also, USB "remote wakeup" signaling is supported, whereby some
103 USB devices (like keyboards and network adapters) can wake up
104 their parent hub. That wakeup cascades up the USB tree, and
105 could wake the system from states like suspend-to-RAM.
107 If you are unsure about this, say N here.
111 depends on USB && EXPERIMENTAL
116 config USB_OTG_WHITELIST
117 bool "Rely on OTG Targeted Peripherals List"
118 depends on USB_OTG || EMBEDDED
120 default n if EMBEDDED
122 If you say Y here, the "otg_whitelist.h" file will be used as a
123 product whitelist, so USB peripherals not listed there will be
124 rejected during enumeration. This behavior is required by the
125 USB OTG specification for all devices not on your product's
126 "Targeted Peripherals List". "Embedded Hosts" are likewise
127 allowed to support only a limited number of peripherals.
129 Otherwise, peripherals not listed there will only generate a
130 warning and enumeration will continue. That's more like what
131 normal Linux-USB hosts do (other than the warning), and is
132 convenient for many stages of product development.
134 config USB_OTG_BLACKLIST_HUB
135 bool "Disable external hubs"
136 depends on USB_OTG || EMBEDDED
138 If you say Y here, then Linux will refuse to enumerate
139 external hubs. OTG hosts are allowed to reduce hardware
140 and software costs by not supporting external hubs. So
141 are "Embedded Hosts" that don't offer OTG support.