# # USB Core configuration # config USB_DEBUG bool "USB verbose debug messages" help Say Y here if you want the USB core & hub drivers to produce a bunch of debug messages to the system log. Select this if you are having a problem with USB support and want to see more of what is going on. config USB_ANNOUNCE_NEW_DEVICES bool "USB announce new devices" default N help Say Y here if you want the USB core to always announce the idVendor, idProduct, Manufacturer, Product, and SerialNumber strings for every new USB device to the syslog. This option is usually used by distro vendors to help with debugging and to let users know what specific device was added to the machine in what location. If you do not want this kind of information sent to the system log, or have any doubts about this, say N here. comment "Miscellaneous USB options" config USB_DEFAULT_PERSIST bool "Enable USB persist by default" default y help Say N here if you don't want USB power session persistance enabled by default. If you say N it will make suspended USB devices that lose power get reenumerated as if they had been unplugged, causing any mounted filesystems to be lost. The persist feature can still be enabled for individual devices through the power/persist sysfs node. See Documentation/usb/persist.txt for more info. If you have any questions about this, say Y here, only say N if you know exactly what you are doing. config USB_DYNAMIC_MINORS bool "Dynamic USB minor allocation" help If you say Y here, the USB subsystem will use dynamic minor allocation for any device that uses the USB major number. This means that you can have more than 16 of a single type of device (like USB printers). If you are unsure about this, say N here. config USB_OTG bool "OTG support" depends on PM_RUNTIME default n help The most notable feature of USB OTG is support for a "Dual-Role" device, which can act as either a device or a host. The initial role is decided by the type of plug inserted and can be changed later when two dual role devices talk to each other. Select this only if your board has Mini-AB/Micro-AB connector. config USB_OTG_WHITELIST bool "Rely on OTG Targeted Peripherals List" depends on USB_OTG || EXPERT default y if USB_OTG help If you say Y here, the "otg_whitelist.h" file will be used as a product whitelist, so USB peripherals not listed there will be rejected during enumeration. This behavior is required by the USB OTG specification for all devices not on your product's "Targeted Peripherals List". "Embedded Hosts" are likewise allowed to support only a limited number of peripherals. Otherwise, peripherals not listed there will only generate a warning and enumeration will continue. That's more like what normal Linux-USB hosts do (other than the warning), and is convenient for many stages of product development. config USB_OTG_BLACKLIST_HUB bool "Disable external hubs" depends on USB_OTG || EXPERT help If you say Y here, then Linux will refuse to enumerate external hubs. OTG hosts are allowed to reduce hardware and software costs by not supporting external hubs. So are "Embedded Hosts" that don't offer OTG support.