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How to configure the Linux kernel/drivers/usb/gadget

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Howto configure the Linux kernel / drivers / usb / gadget

USB Gadget support on a system involves
(a) a peripheral controller, and
(b) the gadget driver using it.
NOTE: Gadget support ** DOES NOT ** depend on host-side CONFIG_USB !!
- Host systems (like PCs) need CONFIG_USB (with "A" jacks).
- Peripherals (like PDAs) need CONFIG_USB_GADGET (with "B" jacks).
- Some systems have both kinds of of controller.
With help from a special transceiver and a "Mini-AB" jack, systems with
both kinds of controller can also support "USB On-the-Go" (CONFIG_USB_OTG).

USB Gadget SupportEdit

  • Option: USB_GADGET
    • Kernel Versions: ...
    • (on/off/module) Support for USB Gadgets
      USB is a master/slave protocol, organized with one master host (such as a PC) controlling up to 127 peripheral devices. The USB hardware is asymmetric, which makes it easier to set up: you can't connect a "to-the-host" connector to a peripheral.
      Linux can run in the host, or in the peripheral. In both cases you need a low level bus controller driver, and some software talking to it. Peripheral controllers are often discrete silicon, or are integrated with the CPU in a microcontroller. The more familiar host side controllers have names like like "EHCI", "OHCI", or "UHCI", and are usually integrated into southbridges on PC motherboards.
      Enable this configuration option if you want to run Linux inside a USB peripheral device. Configure one hardware driver for your peripheral/device side bus controller, and a "gadget driver" for your peripheral protocol. (If you use modular gadget drivers, you may configure more than one.)
      If in doubt, say "N" and don't enable these drivers; most people don't have this kind of hardware (except maybe inside Linux PDAs).
      For more information, see <> and the kernel DocBook documentation for this API.

    • Kernel Versions: ...
    • (on/off) ean Debugging information files
    • depends on USB_GADGET && PROC_FS
      Some of the drivers in the "gadget" framework can expose debugging information in files such as /proc/driver/udc (for a peripheral controller). The information in these files may help when you're troubleshooting or bringing up a driver on a new board. Enable these files by choosing "Y" here. If in doubt, or to conserve kernel memory, say "N".

    • Kernel Versions: ...
    • (on/off) ean
USB Peripheral Controller Support

"USB Peripheral Controller"

    • depends on USB_GADGET
      A USB device uses a controller to talk to its host. Systems should have only one such upstream link. Many controller drivers are platform-specific; these often need board-specific hooks.

  • Option: USB_GADGET_NET2280
    • Kernel Versions: ...
    • (on/off) ean NetChip 2280
    • depends on PCI
      NetChip 2280 is a PCI based USB peripheral controller which supports both full and high speed USB 2.0 data transfers. It has six configurable endpoints, as well as endpoint zero (for control transfers) and several endpoints with dedicated functions.
      Say "y" to link the driver statically, or "m" to build a dynamically linked module called "net2280" and force all gadget drivers to also be dynamically linked.

  • Option: USB_NET2280
    • Kernel Versions: ...
    • (on/off/module)
    • depends on USB_GADGET_NET2280
    • default USB_GADGET

    • Kernel Versions: ...
    • (on/off) ean PXA 25x or IXP 4xx
    • depends on (ARCH_PXA && PXA25x) || ARCH_IXP4XX
      Intel's PXA 25x series XScale ARM-5TE processors include an integrated full speed USB 1.1 device controller. The controller in the IXP 4xx series is register-compatible.
      It has fifteen fixed-function endpoints, as well as endpoint zero (for control transfers).
      Say "y" to link the driver statically, or "m" to build a dynamically linked module called "pxa2xx_udc" and force all gadget drivers to also be dynamically linked.

  • Option: USB_PXA2XX
    • Kernel Versions: ...
    • (on/off/module)
    • depends on USB_GADGET_PXA2XX
    • default USB_GADGET
if there's only one gadget driver, using only two bulk endpoints,
don't waste memory for the other endpoints

  • Option: USB_PXA2XX_SMALL
    • Kernel Versions: ...
    • depends on USB_GADGET_PXA2XX
    • (on/off)
    • default n if USB_ETH_RNDIS
    • default y if USB_ZERO
    • default y if USB_ETH
    • default y if USB_G_SERIAL

    • Kernel Versions: ...
    • (on/off) ean Toshiba TC86C001 'Goku-S'
    • depends on PCI
      The Toshiba TC86C001 is a PCI device which includes controllers for full speed USB devices, IDE, I2C, SIO, plus a USB host (OHCI). The device controller has three configurable (bulk or interrupt) endpoints, plus endpoint zero (for control transfers).
      Say "y" to link the driver statically, or "m" to build a dynamically linked module called "goku_udc" and to force all gadget drivers to also be dynamically linked.

  • Option: USB_GOKU
    • Kernel Versions: ...
    • (on/off/module)
    • depends on USB_GADGET_GOKU
    • default USB_GADGET

  • Option: USB_GADGET_LH7A40X
    • Kernel Versions: ...
    • (on/off) ean LH7A40X
    • depends on ARCH_LH7A40X
      This driver provides USB Device Controller driver for LH7A40x

  • Option: USB_LH7A40X
    • Kernel Versions: ...
    • (on/off/module)
    • depends on USB_GADGET_LH7A40X
    • default USB_GADGET

    • Kernel Versions: ...
    • (on/off) ean OMAP USB Device Controller
    • depends on ARCH_OMAP
    • select ISP1301_OMAP if MACH_OMAP_H2 || MACH_OMAP_H3
      Many Texas Instruments OMAP processors have flexible full speed USB device controllers, with support for up to 30 endpoints (plus endpoint zero). This driver supports the controller in the OMAP 1611, and should work with controllers in other OMAP processors too, given minor tweaks.
      Say "y" to link the driver statically, or "m" to build a dynamically linked module called "omap_udc" and force all gadget drivers to also be dynamically linked.

  • Option: USB_OMAP
    • Kernel Versions: ...
    • (on/off/module)
    • depends on USB_GADGET_OMAP
    • default USB_GADGET

  • Option: USB_OTG
    • Kernel Versions: ...
    • (on/off) ean OTG Support
      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 choice can be changed later, when two dual-role devices talk to each other.
      Select this only if your OMAP board has a Mini-AB connector.

    • Kernel Versions: ...
    • (on/off) ean Dummy HCD (DEVELOPMENT)
    • depends on USB && EXPERIMENTAL
      This host controller driver emulates USB, looping all data transfer requests back to a USB "gadget driver" in the same host. The host side is the master; the gadget side is the slave. Gadget drivers can be high, full, or low speed; and they have access to endpoints like those from NET2280, PXA2xx, or SA1100 hardware. This may help in some stages of creating a driver to embed in a Linux device, since it lets you debug several parts of the gadget driver without its hardware or drivers being involved. Since such a gadget side driver needs to interoperate with a host side Linux-USB device driver, this may help to debug both sides of a USB protocol stack.
      Say "y" to link the driver statically, or "m" to build a dynamically linked module called "dummy_hcd" and force all gadget drivers to also be dynamically linked.

  • Option: USB_DUMMY_HCD
    • Kernel Versions: ...
    • (on/off/module)
    • depends on USB_GADGET_DUMMY_HCD
    • default USB_GADGET
NOTE: Please keep dummy_hcd LAST so that "real hardware" appears
first and will be selected by default.

    • Kernel Versions: ...
    • (on/off)
    • depends on USB_GADGET
    • default n
      Means that gadget drivers should include extra descriptors and code to handle dual-speed controllers.
USB Gadget Drivers
    • (on/off/module) USB Gadget Drivers
    • default USB_ETH
      A Linux "Gadget Driver" talks to the USB Peripheral Controller driver through the abstract "gadget" API. Some other operating systems call these "client" drivers, of which "class drivers" are a subset (implementing a USB device class specification). A gadget driver implements one or more USB functions using the peripheral hardware.
      Gadget drivers are hardware-neutral, or "platform independent", except that they sometimes must understand quirks or limitations of the particular controllers they work with. For example, when a controller doesn't support alternate configurations or provide enough of the right types of endpoints, the gadget driver might not be able work with that controller, or might need to implement a less common variant of a device class protocol.
this first set of drivers all depend on bulk-capable hardware.

  • Option: USB_ZERO
    • Kernel Versions: ...
    • (on/off/module) Gadget Zero (DEVELOPMENT)
    • depends on EXPERIMENTAL
      Gadget Zero is a two-configuration device. It either sinks and sources bulk data; or it loops back a configurable number of transfers. It also implements control requests, for "chapter 9" conformance. The driver needs only two bulk-capable endpoints, so it can work on top of most device-side usb controllers. It's useful for testing, and is also a working example showing how USB "gadget drivers" can be written.
      Make this be the first driver you try using on top of any new USB peripheral controller driver. Then you can use host-side test software, like the "usbtest" driver, to put your hardware and its driver through a basic set of functional tests.
      Gadget Zero also works with the host-side "usb-skeleton" driver, and with many kinds of host-side test software. You may need to tweak product and vendor IDs before host software knows about this device, and arrange to select an appropriate configuration.
      Say "y" to link the driver statically, or "m" to build a dynamically linked module called "g_zero".

    • Kernel Versions: ...
    • (on/off) ean HNP Test Device
    • depends on USB_ZERO && USB_OTG
      You can configure this device to enumerate using the device identifiers of the USB-OTG test device. That means that when this gadget connects to another OTG device, with this one using the "B-Peripheral" role, that device will use HNP to let this one serve as the USB host instead (in the "B-Host" role).

  • Option: USB_ETH
    • Kernel Versions: ...
    • (on/off/module) Ethernet Gadget (with CDC Ethernet support)
    • depends on NET
      This driver implements Ethernet style communication, in either of two ways: - The "Communication Device Class" (CDC) Ethernet Control Model. That protocol is often avoided with pure Ethernet adapters, in favor of simpler vendor-specific hardware, but is widely supported by firmware for smart network devices.
      - On hardware can't implement that protocol, a simple CDC subset is used, placing fewer demands on USB.
      RNDIS support is a third option, more demanding than that subset.
      Within the USB device, this gadget driver exposes a network device usbX, where X depends on what other networking devices you have. Treat it like a two-node Ethernet link: host, and gadget.
      The Linux-USB host-side "usbnet" driver interoperates with this driver, so that deep I/O queues can be supported. On 2.4 kernels, use "CDCEther" instead, if you're using the CDC option. That CDC mode should also interoperate with standard CDC Ethernet class drivers on other host operating systems.
      Say "y" to link the driver statically, or "m" to build a dynamically linked module called "g_ether".

  • Option: USB_ETH_RNDIS
    • Kernel Versions: ...
    • (on/off) RNDIS support (EXPERIMENTAL)
    • depends on USB_ETH && EXPERIMENTAL
    • default y
      Microsoft Windows XP bundles the "Remote NDIS" (RNDIS) protocol, and Microsoft provides redistributable binary RNDIS drivers for older versions of Windows.
      If you say "y" here, the Ethernet gadget driver will try to provide a second device configuration, supporting RNDIS to talk to such Microsoft USB hosts. To make MS-Windows work with this, use Documentation/usb/linux.inf as the "driver info file". For versions of MS-Windows older than XP, you'll need to download drivers from Microsoft's website; a URL is given in comments found in that info file.

  • Option: USB_GADGETFS
    • Kernel Versions: ...
    • (on/off/module) Gadget Filesystem (EXPERIMENTAL)
    • depends on EXPERIMENTAL
      This driver provides a filesystem based API that lets user mode programs implement a single-configuration USB device, including endpoint I/O and control requests that don't relate to enumeration. All endpoints, transfer speeds, and transfer types supported by the hardware are available, through read() and write() calls.
      Say "y" to link the driver statically, or "m" to build a dynamically linked module called "gadgetfs".

    • Kernel Versions: ...
    • (on/off/module) File-backed Storage Gadget
      The File-backed Storage Gadget acts as a USB Mass Storage disk drive. As its storage repository it can use a regular file or a block device (in much the same way as the "loop" device driver), specified as a module parameter.
      Say "y" to link the driver statically, or "m" to build a dynamically linked module called "g_file_storage".

    • Kernel Versions: ...
    • (on/off) File-backed Storage Gadget testing version
    • depends on USB_FILE_STORAGE
    • default n
      Say "y" to generate the larger testing version of the File-backed Storage Gadget, useful for probing the behavior of USB Mass Storage hosts. Not needed for normal operation.

  • Option: USB_G_SERIAL
    • Kernel Versions: ...
    • (on/off/module) Serial Gadget (with CDC ACM support)
      The Serial Gadget talks to the Linux-USB generic serial driver. This driver supports a CDC-ACM module option, which can be used to interoperate with MS-Windows hosts or with the Linux-USB cdc-acm driver.
      Say "y" to link the driver statically, or "m" to build a dynamically linked module called "g_serial".
      For more information, see Documentation/usb/gadget_serial.txt which includes instructions and a "driver info file" needed to make MS-Windows work with this driver.

put drivers that need isochronous transfer support (for audio
or video class gadget drivers), or specific hardware, here.
- none yet

Linux Kernel Configuration


USB Sticks Bedrukken

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