2 # USB Gadget support on a system involves
3 # (a) a peripheral controller, and
4 # (b) the gadget driver using it.
6 # NOTE: Gadget support ** DOES NOT ** depend on host-side CONFIG_USB !!
8 # - Host systems (like PCs) need CONFIG_USB (with "A" jacks).
9 # - Peripherals (like PDAs) need CONFIG_USB_GADGET (with "B" jacks).
10 # - Some systems have both kinds of controllers.
12 # With help from a special transceiver and a "Mini-AB" jack, systems with
13 # both kinds of controller can also support "USB On-the-Go" (CONFIG_USB_OTG).
17 tristate "USB Gadget Support"
20 USB is a master/slave protocol, organized with one master
21 host (such as a PC) controlling up to 127 peripheral devices.
22 The USB hardware is asymmetric, which makes it easier to set up:
23 you can't connect a "to-the-host" connector to a peripheral.
25 Linux can run in the host, or in the peripheral. In both cases
26 you need a low level bus controller driver, and some software
27 talking to it. Peripheral controllers are often discrete silicon,
28 or are integrated with the CPU in a microcontroller. The more
29 familiar host side controllers have names like "EHCI", "OHCI",
30 or "UHCI", and are usually integrated into southbridges on PC
33 Enable this configuration option if you want to run Linux inside
34 a USB peripheral device. Configure one hardware driver for your
35 peripheral/device side bus controller, and a "gadget driver" for
36 your peripheral protocol. (If you use modular gadget drivers,
37 you may configure more than one.)
39 If in doubt, say "N" and don't enable these drivers; most people
40 don't have this kind of hardware (except maybe inside Linux PDAs).
42 For more information, see <http://www.linux-usb.org/gadget> and
43 the kernel DocBook documentation for this API.
47 config USB_GADGET_DEBUG
48 bool "Debugging messages (DEVELOPMENT)"
49 depends on DEBUG_KERNEL
51 Many controller and gadget drivers will print some debugging
52 messages if you use this option to ask for those messages.
54 Avoid enabling these messages, even if you're actively
55 debugging such a driver. Many drivers will emit so many
56 messages that the driver timings are affected, which will
57 either create new failure modes or remove the one you're
58 trying to track down. Never enable these messages for a
61 config USB_GADGET_VERBOSE
62 bool "Verbose debugging Messages (DEVELOPMENT)"
63 depends on USB_GADGET_DEBUG
65 Many controller and gadget drivers will print verbose debugging
66 messages if you use this option to ask for those messages.
68 Avoid enabling these messages, even if you're actively
69 debugging such a driver. Many drivers will emit so many
70 messages that the driver timings are affected, which will
71 either create new failure modes or remove the one you're
72 trying to track down. Never enable these messages for a
75 config USB_GADGET_DEBUG_FILES
76 bool "Debugging information files (DEVELOPMENT)"
79 Some of the drivers in the "gadget" framework can expose
80 debugging information in files such as /proc/driver/udc
81 (for a peripheral controller). The information in these
82 files may help when you're troubleshooting or bringing up a
83 driver on a new board. Enable these files by choosing "Y"
84 here. If in doubt, or to conserve kernel memory, say "N".
86 config USB_GADGET_DEBUG_FS
87 bool "Debugging information files in debugfs (DEVELOPMENT)"
90 Some of the drivers in the "gadget" framework can expose
91 debugging information in files under /sys/kernel/debug/.
92 The information in these files may help when you're
93 troubleshooting or bringing up a driver on a new board.
94 Enable these files by choosing "Y" here. If in doubt, or
95 to conserve kernel memory, say "N".
97 config USB_GADGET_VBUS_DRAW
98 int "Maximum VBUS Power usage (2-500 mA)"
102 Some devices need to draw power from USB when they are
103 configured, perhaps to operate circuitry or to recharge
104 batteries. This is in addition to any local power supply,
105 such as an AC adapter or batteries.
107 Enter the maximum power your device draws through USB, in
108 milliAmperes. The permitted range of values is 2 - 500 mA;
109 0 mA would be legal, but can make some hosts misbehave.
111 This value will be used except for system-specific gadget
112 drivers that have more specific information.
114 config USB_GADGET_STORAGE_NUM_BUFFERS
115 int "Number of storage pipeline buffers"
119 Usually 2 buffers are enough to establish a good buffering
120 pipeline. The number may be increased in order to compensate
121 for a bursty VFS behaviour. For instance there may be CPU wake up
122 latencies that makes the VFS to appear bursty in a system with
123 an CPU on-demand governor. Especially if DMA is doing IO to
124 offload the CPU. In this case the CPU will go into power
125 save often and spin up occasionally to move data within VFS.
126 If selecting USB_GADGET_DEBUG_FILES this value may be set by
127 a module parameter as well.
130 source "drivers/usb/gadget/udc/Kconfig"
136 # composite based drivers
137 config USB_LIBCOMPOSITE
140 depends on USB_GADGET
178 config USB_F_MASS_STORAGE
208 config USB_F_AUDIO_SRC
215 tristate "USB Gadget Drivers"
218 A Linux "Gadget Driver" talks to the USB Peripheral Controller
219 driver through the abstract "gadget" API. Some other operating
220 systems call these "client" drivers, of which "class drivers"
221 are a subset (implementing a USB device class specification).
222 A gadget driver implements one or more USB functions using
223 the peripheral hardware.
225 Gadget drivers are hardware-neutral, or "platform independent",
226 except that they sometimes must understand quirks or limitations
227 of the particular controllers they work with. For example, when
228 a controller doesn't support alternate configurations or provide
229 enough of the right types of endpoints, the gadget driver might
230 not be able work with that controller, or might need to implement
231 a less common variant of a device class protocol.
233 # this first set of drivers all depend on bulk-capable hardware.
236 tristate "USB functions configurable through configfs"
237 select USB_LIBCOMPOSITE
239 A Linux USB "gadget" can be set up through configfs.
240 If this is the case, the USB functions (which from the host's
241 perspective are seen as interfaces) and configurations are
242 specified simply by creating appropriate directories in configfs.
243 Associating functions with configurations is done by creating
244 appropriate symbolic links.
245 For more information see Documentation/usb/gadget_configfs.txt.
247 config USB_CONFIGFS_SERIAL
248 bool "Generic serial bulk in/out"
249 depends on USB_CONFIGFS
254 The function talks to the Linux-USB generic serial driver.
256 config USB_CONFIGFS_ACM
257 bool "Abstract Control Model (CDC ACM)"
258 depends on USB_CONFIGFS
263 ACM serial link. This function can be used to interoperate with
264 MS-Windows hosts or with the Linux-USB "cdc-acm" driver.
266 config USB_CONFIGFS_OBEX
267 bool "Object Exchange Model (CDC OBEX)"
268 depends on USB_CONFIGFS
273 You will need a user space OBEX server talking to /dev/ttyGS*,
274 since the kernel itself doesn't implement the OBEX protocol.
276 config USB_CONFIGFS_NCM
277 bool "Network Control Model (CDC NCM)"
278 depends on USB_CONFIGFS
283 NCM is an advanced protocol for Ethernet encapsulation, allows
284 grouping of several ethernet frames into one USB transfer and
285 different alignment possibilities.
287 config USB_CONFIGFS_ECM
288 bool "Ethernet Control Model (CDC ECM)"
289 depends on USB_CONFIGFS
294 The "Communication Device Class" (CDC) Ethernet Control Model.
295 That protocol is often avoided with pure Ethernet adapters, in
296 favor of simpler vendor-specific hardware, but is widely
297 supported by firmware for smart network devices.
299 config USB_CONFIGFS_ECM_SUBSET
300 bool "Ethernet Control Model (CDC ECM) subset"
301 depends on USB_CONFIGFS
306 On hardware that can't implement the full protocol,
307 a simple CDC subset is used, placing fewer demands on USB.
309 config USB_CONFIGFS_RNDIS
311 depends on USB_CONFIGFS
316 Microsoft Windows XP bundles the "Remote NDIS" (RNDIS) protocol,
317 and Microsoft provides redistributable binary RNDIS drivers for
318 older versions of Windows.
320 To make MS-Windows work with this, use Documentation/usb/linux.inf
321 as the "driver info file". For versions of MS-Windows older than
322 XP, you'll need to download drivers from Microsoft's website; a URL
323 is given in comments found in that info file.
325 config USB_CONFIGFS_EEM
326 bool "Ethernet Emulation Model (EEM)"
327 depends on USB_CONFIGFS
332 CDC EEM is a newer USB standard that is somewhat simpler than CDC ECM
333 and therefore can be supported by more hardware. Technically ECM and
334 EEM are designed for different applications. The ECM model extends
335 the network interface to the target (e.g. a USB cable modem), and the
336 EEM model is for mobile devices to communicate with hosts using
337 ethernet over USB. For Linux gadgets, however, the interface with
338 the host is the same (a usbX device), so the differences are minimal.
340 config USB_CONFIGFS_PHONET
341 bool "Phonet protocol"
342 depends on USB_CONFIGFS
348 The Phonet protocol implementation for USB device.
350 config USB_CONFIGFS_MASS_STORAGE
352 depends on USB_CONFIGFS
354 select USB_F_MASS_STORAGE
356 The Mass Storage Gadget acts as a USB Mass Storage disk drive.
357 As its storage repository it can use a regular file or a block
358 device (in much the same way as the "loop" device driver),
359 specified as a module parameter or sysfs option.
361 config USB_CONFIGFS_F_LB_SS
362 bool "Loopback and sourcesink function (for testing)"
363 depends on USB_CONFIGFS
366 Loopback function loops back a configurable number of transfers.
367 Sourcesink function either sinks and sources bulk data.
368 It also implements control requests, for "chapter 9" conformance.
369 Make this be the first driver you try using on top of any new
370 USB peripheral controller driver. Then you can use host-side
371 test software, like the "usbtest" driver, to put your hardware
372 and its driver through a basic set of functional tests.
374 config USB_CONFIGFS_F_FS
375 bool "Function filesystem (FunctionFS)"
376 depends on USB_CONFIGFS
379 The Function Filesystem (FunctionFS) lets one create USB
380 composite functions in user space in the same way GadgetFS
381 lets one create USB gadgets in user space. This allows creation
382 of composite gadgets such that some of the functions are
383 implemented in kernel space (for instance Ethernet, serial or
384 mass storage) and other are implemented in user space.
386 config USB_CONFIGFS_F_MTP
388 depends on USB_CONFIGFS
391 USB gadget MTP support
393 config USB_CONFIGFS_F_PTP
395 depends on USB_CONFIGFS && USB_CONFIGFS_F_MTP
398 USB gadget PTP support
400 config USB_CONFIGFS_F_ACC
401 boolean "Accessory gadget"
402 depends on USB_CONFIGFS
405 USB gadget Accessory support
407 config USB_CONFIGFS_F_AUDIO_SRC
408 boolean "Audio Source gadget"
409 depends on USB_CONFIGFS && USB_CONFIGFS_F_ACC
412 select USB_F_AUDIO_SRC
414 USB gadget Audio Source support
416 config USB_CONFIGFS_UEVENT
417 boolean "Uevent notification of Gadget state"
418 depends on USB_CONFIGFS
420 Enable uevent notifications to userspace when the gadget
421 state changes. The gadget can be in any of the following
422 three states: "CONNECTED/DISCONNECTED/CONFIGURED"
424 config USB_CONFIGFS_F_UAC1
425 bool "Audio Class 1.0"
426 depends on USB_CONFIGFS
428 select USB_LIBCOMPOSITE
432 This Audio function implements 1 AudioControl interface,
433 1 AudioStreaming Interface each for USB-OUT and USB-IN.
434 This driver requires a real Audio codec to be present
437 config USB_CONFIGFS_F_UAC2
438 bool "Audio Class 2.0"
439 depends on USB_CONFIGFS
441 select USB_LIBCOMPOSITE
445 This Audio function is compatible with USB Audio Class
446 specification 2.0. It implements 1 AudioControl interface,
447 1 AudioStreaming Interface each for USB-OUT and USB-IN.
448 This driver doesn't expect any real Audio codec to be present
449 on the device - the audio streams are simply sinked to and
450 sourced from a virtual ALSA sound card created. The user-space
451 application may choose to do whatever it wants with the data
452 received from the USB Host and choose to provide whatever it
453 wants as audio data to the USB Host.
455 config USB_CONFIGFS_F_MIDI
457 depends on USB_CONFIGFS
459 select USB_LIBCOMPOSITE
463 The MIDI Function acts as a USB Audio device, with one MIDI
464 input and one MIDI output. These MIDI jacks appear as
465 a sound "card" in the ALSA sound system. Other MIDI
466 connections can then be made on the gadget system, using
467 ALSA's aconnect utility etc.
469 config USB_CONFIGFS_F_HID
471 depends on USB_CONFIGFS
474 The HID function driver provides generic emulation of USB
475 Human Interface Devices (HID).
477 For more information, see Documentation/usb/gadget_hid.txt.
479 config USB_CONFIGFS_F_UVC
480 bool "USB Webcam function"
481 depends on USB_CONFIGFS
483 select VIDEOBUF2_VMALLOC
486 The Webcam function acts as a composite USB Audio and Video Class
487 device. It provides a userspace API to process UVC control requests
488 and stream video data to the host.
490 config USB_CONFIGFS_F_PRINTER
491 bool "Printer function"
493 depends on USB_CONFIGFS
495 The Printer function channels data between the USB host and a
496 userspace program driving the print engine. The user space
497 program reads and writes the device file /dev/g_printer<X> to
498 receive or send printer data. It can use ioctl calls to
499 the device file to get or set printer status.
501 For more information, see Documentation/usb/gadget_printer.txt
502 which includes sample code for accessing the device file.
504 source "drivers/usb/gadget/legacy/Kconfig"