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 12config USB_ANNOUNCE_NEW_DEVICES 13 bool "USB announce new devices" 14 depends on USB 15 default N 16 help 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 22 in what location. 23 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. 26 27comment "Miscellaneous USB options" 28 depends on USB 29 30config USB_DEVICEFS 31 bool "USB device filesystem (DEPRECATED)" 32 depends on USB 33 ---help--- 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. 42 43 You may need to mount the usbfs file system to see the files, use 44 mount -t usbfs none /proc/bus/usb 45 46 For the format of the various /proc/bus/usb/ files, please read 47 <file:Documentation/usb/proc_usb_info.txt>. 48 49 Modern Linux systems do not use this. 50 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 54 system. 55 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. 58 59config USB_DEVICE_CLASS 60 bool "USB device class-devices (DEPRECATED)" 61 depends on USB 62 default y 63 ---help--- 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. 67 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. 75 76 This option provides backward compatibility for libusb device 77 nodes (lsusb) when usbfs is not used, and the following udev rule 78 doesn't exist: 79 SUBSYSTEM=="usb", ACTION=="add", ENV{DEVTYPE}=="usb_device", \ 80 NAME="bus/usb/$env{BUSNUM}/$env{DEVNUM}", MODE="0644" 81 82config USB_DYNAMIC_MINORS 83 bool "Dynamic USB minor allocation" 84 depends on USB 85 help 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). 90 91 If you are unsure about this, say N here. 92 93config USB_SUSPEND 94 bool "USB runtime power management (autosuspend) and wakeup" 95 depends on USB && PM_RUNTIME 96 help 97 If you say Y here, you can use driver calls or the sysfs 98 "power/control" file to enable or disable autosuspend for 99 individual USB peripherals (see 100 Documentation/usb/power-management.txt for more details). 101 102 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. 106 107 If you are unsure about this, say N here. 108 109config USB_OTG 110 bool 111 depends on USB && EXPERIMENTAL 112 depends on USB_SUSPEND 113 default n 114 115 116config USB_OTG_WHITELIST 117 bool "Rely on OTG Targeted Peripherals List" 118 depends on USB_OTG || EMBEDDED 119 default y if USB_OTG 120 default n if EMBEDDED 121 help 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. 128 129 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. 133 134config USB_OTG_BLACKLIST_HUB 135 bool "Disable external hubs" 136 depends on USB_OTG || EMBEDDED 137 help 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. 142 143