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 n 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 contains 51 the device node, the other device contains the interface data. Both 52 devices are at the same level in sysfs (siblings) and one can't access 53 the other. The device node created directly by the usbdev is the parent 54 device of the interface and therefore easily accessible from the interface 55 event. 56 57 This option provides backward compatibility if needed. 58 59config USB_DYNAMIC_MINORS 60 bool "Dynamic USB minor allocation (EXPERIMENTAL)" 61 depends on USB && EXPERIMENTAL 62 help 63 If you say Y here, the USB subsystem will use dynamic minor 64 allocation for any device that uses the USB major number. 65 This means that you can have more than 16 of a single type 66 of device (like USB printers). 67 68 If you are unsure about this, say N here. 69 70config USB_SUSPEND 71 bool "USB selective suspend/resume and wakeup (EXPERIMENTAL)" 72 depends on USB && PM && EXPERIMENTAL 73 help 74 If you say Y here, you can use driver calls or the sysfs 75 "power/state" file to suspend or resume individual USB 76 peripherals. 77 78 Also, USB "remote wakeup" signaling is supported, whereby some 79 USB devices (like keyboards and network adapters) can wake up 80 their parent hub. That wakeup cascades up the USB tree, and 81 could wake the system from states like suspend-to-RAM. 82 83 If you are unsure about this, say N here. 84 85config USB_OTG 86 bool 87 depends on USB && EXPERIMENTAL 88 select USB_SUSPEND 89 default n 90 91 92config USB_OTG_WHITELIST 93 bool "Rely on OTG Targeted Peripherals List" 94 depends on USB_OTG 95 default y 96 help 97 If you say Y here, the "otg_whitelist.h" file will be used as a 98 product whitelist, so USB peripherals not listed there will be 99 rejected during enumeration. This behavior is required by the 100 USB OTG specification for all devices not on your product's 101 "Targeted Peripherals List". 102 103 Otherwise, peripherals not listed there will only generate a 104 warning and enumeration will continue. That's more like what 105 normal Linux-USB hosts do (other than the warning), and is 106 convenient for many stages of product development. 107 108config USB_OTG_BLACKLIST_HUB 109 bool "Disable external hubs" 110 depends on USB_OTG 111 help 112 If you say Y here, then Linux will refuse to enumerate 113 external hubs. OTG hosts are allowed to reduce hardware 114 and software costs by not supporting external hubs. 115 116