| # SPDX-License-Identifier: GPL-2.0 |
| # |
| # 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 controllers. |
| # |
| # 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). |
| # |
| |
| menuconfig USB_GADGET |
| tristate "USB Gadget Support" |
| select USB_COMMON |
| select NLS |
| help |
| 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 "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 <http://www.linux-usb.org/gadget> and |
| the kernel documentation for this API. |
| |
| if USB_GADGET |
| |
| config USB_GADGET_DEBUG |
| bool "Debugging messages (DEVELOPMENT)" |
| depends on DEBUG_KERNEL |
| help |
| Many controller and gadget drivers will print some debugging |
| messages if you use this option to ask for those messages. |
| |
| Avoid enabling these messages, even if you're actively |
| debugging such a driver. Many drivers will emit so many |
| messages that the driver timings are affected, which will |
| either create new failure modes or remove the one you're |
| trying to track down. Never enable these messages for a |
| production build. |
| |
| config USB_GADGET_VERBOSE |
| bool "Verbose debugging Messages (DEVELOPMENT)" |
| depends on USB_GADGET_DEBUG |
| help |
| Many controller and gadget drivers will print verbose debugging |
| messages if you use this option to ask for those messages. |
| |
| Avoid enabling these messages, even if you're actively |
| debugging such a driver. Many drivers will emit so many |
| messages that the driver timings are affected, which will |
| either create new failure modes or remove the one you're |
| trying to track down. Never enable these messages for a |
| production build. |
| |
| config USB_GADGET_DEBUG_FILES |
| bool "Debugging information files (DEVELOPMENT)" |
| depends on PROC_FS |
| help |
| 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". |
| |
| config USB_GADGET_DEBUG_FS |
| bool "Debugging information files in debugfs (DEVELOPMENT)" |
| depends on DEBUG_FS |
| help |
| Some of the drivers in the "gadget" framework can expose |
| debugging information in files under /sys/kernel/debug/. |
| 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". |
| |
| config USB_GADGET_VBUS_DRAW |
| int "Maximum VBUS Power usage (2-500 mA)" |
| range 2 500 |
| default 2 |
| help |
| Some devices need to draw power from USB when they are |
| configured, perhaps to operate circuitry or to recharge |
| batteries. This is in addition to any local power supply, |
| such as an AC adapter or batteries. |
| |
| Enter the maximum power your device draws through USB, in |
| milliAmperes. The permitted range of values is 2 - 500 mA; |
| 0 mA would be legal, but can make some hosts misbehave. |
| |
| This value will be used except for system-specific gadget |
| drivers that have more specific information. |
| |
| config USB_GADGET_STORAGE_NUM_BUFFERS |
| int "Number of storage pipeline buffers" |
| range 2 256 |
| default 2 |
| help |
| Usually 2 buffers are enough to establish a good buffering |
| pipeline. The number may be increased in order to compensate |
| for a bursty VFS behaviour. For instance there may be CPU wake up |
| latencies that makes the VFS to appear bursty in a system with |
| an CPU on-demand governor. Especially if DMA is doing IO to |
| offload the CPU. In this case the CPU will go into power |
| save often and spin up occasionally to move data within VFS. |
| If selecting USB_GADGET_DEBUG_FILES this value may be set by |
| a module parameter as well. |
| If unsure, say 2. |
| |
| config U_SERIAL_CONSOLE |
| bool "Serial gadget console support" |
| depends on USB_U_SERIAL |
| help |
| It supports the serial gadget can be used as a console. |
| |
| source "drivers/usb/gadget/udc/Kconfig" |
| |
| # |
| # USB Gadget Drivers |
| # |
| |
| # composite based drivers |
| config USB_LIBCOMPOSITE |
| tristate |
| select CONFIGFS_FS |
| depends on USB_GADGET |
| |
| config USB_F_ACM |
| tristate |
| |
| config USB_F_SS_LB |
| tristate |
| |
| config USB_U_SERIAL |
| tristate |
| |
| config USB_U_ETHER |
| tristate |
| |
| config USB_U_AUDIO |
| tristate |
| |
| config USB_F_SERIAL |
| tristate |
| |
| config USB_F_OBEX |
| tristate |
| |
| config USB_F_NCM |
| tristate |
| |
| config USB_F_ECM |
| tristate |
| |
| config USB_F_PHONET |
| tristate |
| |
| config USB_F_EEM |
| tristate |
| |
| config USB_F_SUBSET |
| tristate |
| |
| config USB_F_RNDIS |
| tristate |
| |
| config USB_F_MASS_STORAGE |
| tristate |
| |
| config USB_F_FS |
| tristate |
| |
| config USB_F_UAC1 |
| tristate |
| |
| config USB_F_UAC1_LEGACY |
| tristate |
| |
| config USB_F_UAC2 |
| tristate |
| |
| config USB_F_UVC |
| tristate |
| |
| config USB_F_MIDI |
| tristate |
| |
| config USB_F_HID |
| tristate |
| |
| config USB_F_PRINTER |
| tristate |
| |
| config USB_F_TCM |
| tristate |
| |
| # this first set of drivers all depend on bulk-capable hardware. |
| |
| config USB_CONFIGFS |
| tristate "USB Gadget functions configurable through configfs" |
| select USB_LIBCOMPOSITE |
| help |
| A Linux USB "gadget" can be set up through configfs. |
| If this is the case, the USB functions (which from the host's |
| perspective are seen as interfaces) and configurations are |
| specified simply by creating appropriate directories in configfs. |
| Associating functions with configurations is done by creating |
| appropriate symbolic links. |
| For more information see Documentation/usb/gadget_configfs.rst. |
| |
| config USB_CONFIGFS_SERIAL |
| bool "Generic serial bulk in/out" |
| depends on USB_CONFIGFS |
| depends on TTY |
| select USB_U_SERIAL |
| select USB_F_SERIAL |
| help |
| The function talks to the Linux-USB generic serial driver. |
| |
| config USB_CONFIGFS_ACM |
| bool "Abstract Control Model (CDC ACM)" |
| depends on USB_CONFIGFS |
| depends on TTY |
| select USB_U_SERIAL |
| select USB_F_ACM |
| help |
| ACM serial link. This function can be used to interoperate with |
| MS-Windows hosts or with the Linux-USB "cdc-acm" driver. |
| |
| config USB_CONFIGFS_OBEX |
| bool "Object Exchange Model (CDC OBEX)" |
| depends on USB_CONFIGFS |
| depends on TTY |
| select USB_U_SERIAL |
| select USB_F_OBEX |
| help |
| You will need a user space OBEX server talking to /dev/ttyGS*, |
| since the kernel itself doesn't implement the OBEX protocol. |
| |
| config USB_CONFIGFS_NCM |
| bool "Network Control Model (CDC NCM)" |
| depends on USB_CONFIGFS |
| depends on NET |
| select USB_U_ETHER |
| select USB_F_NCM |
| help |
| NCM is an advanced protocol for Ethernet encapsulation, allows |
| grouping of several ethernet frames into one USB transfer and |
| different alignment possibilities. |
| |
| config USB_CONFIGFS_ECM |
| bool "Ethernet Control Model (CDC ECM)" |
| depends on USB_CONFIGFS |
| depends on NET |
| select USB_U_ETHER |
| select USB_F_ECM |
| help |
| 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. |
| |
| config USB_CONFIGFS_ECM_SUBSET |
| bool "Ethernet Control Model (CDC ECM) subset" |
| depends on USB_CONFIGFS |
| depends on NET |
| select USB_U_ETHER |
| select USB_F_SUBSET |
| help |
| On hardware that can't implement the full protocol, |
| a simple CDC subset is used, placing fewer demands on USB. |
| |
| config USB_CONFIGFS_RNDIS |
| bool "RNDIS" |
| depends on USB_CONFIGFS |
| depends on NET |
| select USB_U_ETHER |
| select USB_F_RNDIS |
| help |
| Microsoft Windows XP bundles the "Remote NDIS" (RNDIS) protocol, |
| and Microsoft provides redistributable binary RNDIS drivers for |
| older versions of Windows. |
| |
| 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. |
| |
| config USB_CONFIGFS_EEM |
| bool "Ethernet Emulation Model (EEM)" |
| depends on USB_CONFIGFS |
| depends on NET |
| select USB_U_ETHER |
| select USB_F_EEM |
| help |
| CDC EEM is a newer USB standard that is somewhat simpler than CDC ECM |
| and therefore can be supported by more hardware. Technically ECM and |
| EEM are designed for different applications. The ECM model extends |
| the network interface to the target (e.g. a USB cable modem), and the |
| EEM model is for mobile devices to communicate with hosts using |
| ethernet over USB. For Linux gadgets, however, the interface with |
| the host is the same (a usbX device), so the differences are minimal. |
| |
| config USB_CONFIGFS_PHONET |
| bool "Phonet protocol" |
| depends on USB_CONFIGFS |
| depends on NET |
| depends on PHONET |
| select USB_U_ETHER |
| select USB_F_PHONET |
| help |
| The Phonet protocol implementation for USB device. |
| |
| config USB_CONFIGFS_MASS_STORAGE |
| bool "Mass storage" |
| depends on USB_CONFIGFS |
| depends on BLOCK |
| select USB_F_MASS_STORAGE |
| help |
| The Mass 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 or sysfs option. |
| |
| config USB_CONFIGFS_F_LB_SS |
| bool "Loopback and sourcesink function (for testing)" |
| depends on USB_CONFIGFS |
| select USB_F_SS_LB |
| help |
| Loopback function loops back a configurable number of transfers. |
| Sourcesink function either sinks and sources bulk data. |
| It also implements control requests, for "chapter 9" conformance. |
| 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. |
| |
| config USB_CONFIGFS_F_FS |
| bool "Function filesystem (FunctionFS)" |
| depends on USB_CONFIGFS |
| select USB_F_FS |
| help |
| The Function Filesystem (FunctionFS) lets one create USB |
| composite functions in user space in the same way GadgetFS |
| lets one create USB gadgets in user space. This allows creation |
| of composite gadgets such that some of the functions are |
| implemented in kernel space (for instance Ethernet, serial or |
| mass storage) and other are implemented in user space. |
| |
| config USB_CONFIGFS_F_UAC1 |
| bool "Audio Class 1.0" |
| depends on USB_CONFIGFS |
| depends on SND |
| select USB_LIBCOMPOSITE |
| select SND_PCM |
| select USB_U_AUDIO |
| select USB_F_UAC1 |
| help |
| This Audio function implements 1 AudioControl interface, |
| 1 AudioStreaming Interface each for USB-OUT and USB-IN. |
| This driver doesn't expect any real Audio codec to be present |
| on the device - the audio streams are simply sinked to and |
| sourced from a virtual ALSA sound card created. The user-space |
| application may choose to do whatever it wants with the data |
| received from the USB Host and choose to provide whatever it |
| wants as audio data to the USB Host. |
| |
| config USB_CONFIGFS_F_UAC1_LEGACY |
| bool "Audio Class 1.0 (legacy implementation)" |
| depends on USB_CONFIGFS |
| depends on SND |
| select USB_LIBCOMPOSITE |
| select SND_PCM |
| select USB_F_UAC1_LEGACY |
| help |
| This Audio function implements 1 AudioControl interface, |
| 1 AudioStreaming Interface each for USB-OUT and USB-IN. |
| This is a legacy driver and requires a real Audio codec |
| to be present on the device. |
| |
| config USB_CONFIGFS_F_UAC2 |
| bool "Audio Class 2.0" |
| depends on USB_CONFIGFS |
| depends on SND |
| select USB_LIBCOMPOSITE |
| select SND_PCM |
| select USB_U_AUDIO |
| select USB_F_UAC2 |
| help |
| This Audio function is compatible with USB Audio Class |
| specification 2.0. It implements 1 AudioControl interface, |
| 1 AudioStreaming Interface each for USB-OUT and USB-IN. |
| This driver doesn't expect any real Audio codec to be present |
| on the device - the audio streams are simply sinked to and |
| sourced from a virtual ALSA sound card created. The user-space |
| application may choose to do whatever it wants with the data |
| received from the USB Host and choose to provide whatever it |
| wants as audio data to the USB Host. |
| |
| config USB_CONFIGFS_F_MIDI |
| bool "MIDI function" |
| depends on USB_CONFIGFS |
| depends on SND |
| select USB_LIBCOMPOSITE |
| select SND_RAWMIDI |
| select USB_F_MIDI |
| help |
| The MIDI Function acts as a USB Audio device, with one MIDI |
| input and one MIDI output. These MIDI jacks appear as |
| a sound "card" in the ALSA sound system. Other MIDI |
| connections can then be made on the gadget system, using |
| ALSA's aconnect utility etc. |
| |
| config USB_CONFIGFS_F_HID |
| bool "HID function" |
| depends on USB_CONFIGFS |
| select USB_F_HID |
| help |
| The HID function driver provides generic emulation of USB |
| Human Interface Devices (HID). |
| |
| For more information, see Documentation/usb/gadget_hid.rst. |
| |
| config USB_CONFIGFS_F_UVC |
| bool "USB Webcam function" |
| depends on USB_CONFIGFS |
| depends on VIDEO_V4L2 |
| depends on VIDEO_DEV |
| select VIDEOBUF2_VMALLOC |
| select USB_F_UVC |
| help |
| The Webcam function acts as a composite USB Audio and Video Class |
| device. It provides a userspace API to process UVC control requests |
| and stream video data to the host. |
| |
| config USB_CONFIGFS_F_PRINTER |
| bool "Printer function" |
| select USB_F_PRINTER |
| depends on USB_CONFIGFS |
| help |
| The Printer function channels data between the USB host and a |
| userspace program driving the print engine. The user space |
| program reads and writes the device file /dev/g_printer<X> to |
| receive or send printer data. It can use ioctl calls to |
| the device file to get or set printer status. |
| |
| For more information, see Documentation/usb/gadget_printer.rst |
| which includes sample code for accessing the device file. |
| |
| config USB_CONFIGFS_F_TCM |
| bool "USB Gadget Target Fabric" |
| depends on TARGET_CORE |
| depends on USB_CONFIGFS |
| select USB_LIBCOMPOSITE |
| select USB_F_TCM |
| help |
| This fabric is a USB gadget component. Two USB protocols are |
| supported that is BBB or BOT (Bulk Only Transport) and UAS |
| (USB Attached SCSI). BOT is advertised on alternative |
| interface 0 (primary) and UAS is on alternative interface 1. |
| Both protocols can work on USB2.0 and USB3.0. |
| UAS utilizes the USB 3.0 feature called streams support. |
| |
| source "drivers/usb/gadget/legacy/Kconfig" |
| |
| endif # USB_GADGET |