1# 2# USB Core configuration 3# 4config USB_DEBUG 5 bool "USB verbose debug messages" 6 depends on USB 7 help 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. 11 12comment "Miscellaneous USB options" 13 depends on USB 14 15config USB_DEVICEFS 16 bool "USB device filesystem" 17 depends on USB 18 ---help--- 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. 27 28 You may need to mount the usbfs file system to see the files, use 29 mount -t usbfs none /proc/bus/usb 30 31 For the format of the various /proc/bus/usb/ files, please read 32 <file:Documentation/usb/proc_usb_info.txt>. 33 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 38 are used by libusb. 39 40config USB_DEVICE_CLASS 41 bool "USB device class-devices (DEPRECATED)" 42 depends on USB 43 default y 44 ---help--- 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. 48 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. 56 57 This option provides backward compatibility for libusb device 58 nodes (lsusb) when usbfs is not used, and the following udev rule 59 doesn't exist: 60 SUBSYSTEM=="usb", ACTION=="add", ENV{DEVTYPE}=="usb_device", \ 61 NAME="bus/usb/$env{BUSNUM}/$env{DEVNUM}", MODE="0644" 62 63config USB_DYNAMIC_MINORS 64 bool "Dynamic USB minor allocation (EXPERIMENTAL)" 65 depends on USB && EXPERIMENTAL 66 help 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). 71 72 If you are unsure about this, say N here. 73 74config USB_SUSPEND 75 bool "USB selective suspend/resume and wakeup (EXPERIMENTAL)" 76 depends on USB && PM && EXPERIMENTAL 77 help 78 If you say Y here, you can use driver calls or the sysfs 79 "power/state" file to suspend or resume individual USB 80 peripherals. 81 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. 86 87 If you are unsure about this, say N here. 88 89config USB_OTG 90 bool 91 depends on USB && EXPERIMENTAL 92 select USB_SUSPEND 93 default n 94 95 96config USB_OTG_WHITELIST 97 bool "Rely on OTG Targeted Peripherals List" 98 depends on USB_OTG 99 default y 100 help 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". 106 107 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. 111 112config USB_OTG_BLACKLIST_HUB 113 bool "Disable external hubs" 114 depends on USB_OTG 115 help 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. 119