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1#
2# USB Gadget support on a system involves
3# (a) a peripheral controller, and
4# (b) the gadget driver using it.
5#
6# NOTE: Gadget support ** DOES NOT ** depend on host-side CONFIG_USB !!
7#
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.
11#
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).
14#
15
16menuconfig USB_GADGET
17 tristate "USB Gadget Support"
18 select USB_COMMON
19 select NLS
20 help
21 USB is a master/slave protocol, organized with one master
22 host (such as a PC) controlling up to 127 peripheral devices.
23 The USB hardware is asymmetric, which makes it easier to set up:
24 you can't connect a "to-the-host" connector to a peripheral.
25
26 Linux can run in the host, or in the peripheral. In both cases
27 you need a low level bus controller driver, and some software
28 talking to it. Peripheral controllers are often discrete silicon,
29 or are integrated with the CPU in a microcontroller. The more
30 familiar host side controllers have names like "EHCI", "OHCI",
31 or "UHCI", and are usually integrated into southbridges on PC
32 motherboards.
33
34 Enable this configuration option if you want to run Linux inside
35 a USB peripheral device. Configure one hardware driver for your
36 peripheral/device side bus controller, and a "gadget driver" for
37 your peripheral protocol. (If you use modular gadget drivers,
38 you may configure more than one.)
39
40 If in doubt, say "N" and don't enable these drivers; most people
41 don't have this kind of hardware (except maybe inside Linux PDAs).
42
43 For more information, see <http://www.linux-usb.org/gadget> and
44 the kernel documentation for this API.
45
46if USB_GADGET
47
48config USB_GADGET_DEBUG
49 bool "Debugging messages (DEVELOPMENT)"
50 depends on DEBUG_KERNEL
51 help
52 Many controller and gadget drivers will print some debugging
53 messages if you use this option to ask for those messages.
54
55 Avoid enabling these messages, even if you're actively
56 debugging such a driver. Many drivers will emit so many
57 messages that the driver timings are affected, which will
58 either create new failure modes or remove the one you're
59 trying to track down. Never enable these messages for a
60 production build.
61
62config USB_GADGET_VERBOSE
63 bool "Verbose debugging Messages (DEVELOPMENT)"
64 depends on USB_GADGET_DEBUG
65 help
66 Many controller and gadget drivers will print verbose debugging
67 messages if you use this option to ask for those messages.
68
69 Avoid enabling these messages, even if you're actively
70 debugging such a driver. Many drivers will emit so many
71 messages that the driver timings are affected, which will
72 either create new failure modes or remove the one you're
73 trying to track down. Never enable these messages for a
74 production build.
75
76config USB_GADGET_DEBUG_FILES
77 bool "Debugging information files (DEVELOPMENT)"
78 depends on PROC_FS
79 help
80 Some of the drivers in the "gadget" framework can expose
81 debugging information in files such as /proc/driver/udc
82 (for a peripheral controller). The information in these
83 files may help when you're troubleshooting or bringing up a
84 driver on a new board. Enable these files by choosing "Y"
85 here. If in doubt, or to conserve kernel memory, say "N".
86
87config USB_GADGET_DEBUG_FS
88 bool "Debugging information files in debugfs (DEVELOPMENT)"
89 depends on DEBUG_FS
90 help
91 Some of the drivers in the "gadget" framework can expose
92 debugging information in files under /sys/kernel/debug/.
93 The information in these files may help when you're
94 troubleshooting or bringing up a driver on a new board.
95 Enable these files by choosing "Y" here. If in doubt, or
96 to conserve kernel memory, say "N".
97
98config USB_GADGET_VBUS_DRAW
99 int "Maximum VBUS Power usage (2-500 mA)"
100 range 2 500
101 default 2
102 help
103 Some devices need to draw power from USB when they are
104 configured, perhaps to operate circuitry or to recharge
105 batteries. This is in addition to any local power supply,
106 such as an AC adapter or batteries.
107
108 Enter the maximum power your device draws through USB, in
109 milliAmperes. The permitted range of values is 2 - 500 mA;
110 0 mA would be legal, but can make some hosts misbehave.
111
112 This value will be used except for system-specific gadget
113 drivers that have more specific information.
114
115config USB_GADGET_STORAGE_NUM_BUFFERS
116 int "Number of storage pipeline buffers"
117 range 2 256
118 default 2
119 help
120 Usually 2 buffers are enough to establish a good buffering
121 pipeline. The number may be increased in order to compensate
122 for a bursty VFS behaviour. For instance there may be CPU wake up
123 latencies that makes the VFS to appear bursty in a system with
124 an CPU on-demand governor. Especially if DMA is doing IO to
125 offload the CPU. In this case the CPU will go into power
126 save often and spin up occasionally to move data within VFS.
127 If selecting USB_GADGET_DEBUG_FILES this value may be set by
128 a module parameter as well.
129 If unsure, say 2.
130
131config U_SERIAL_CONSOLE
132 bool "Serial gadget console support"
133 depends on USB_U_SERIAL
134 help
135 It supports the serial gadget can be used as a console.
136
137source "drivers/usb/gadget/udc/Kconfig"
138
139#
140# USB Gadget Drivers
141#
142
143# composite based drivers
144config USB_LIBCOMPOSITE
145 tristate
146 select CONFIGFS_FS
147 depends on USB_GADGET
148
149config USB_F_ACM
150 tristate
151
152config USB_F_SS_LB
153 tristate
154
155config USB_U_SERIAL
156 tristate
157
158config USB_U_ETHER
159 tristate
160
161config USB_U_AUDIO
162 tristate
163
164config USB_F_SERIAL
165 tristate
166
167config USB_F_OBEX
168 tristate
169
170config USB_F_NCM
171 tristate
172
173config USB_F_ECM
174 tristate
175
176config USB_F_PHONET
177 tristate
178
179config USB_F_EEM
180 tristate
181
182config USB_F_SUBSET
183 tristate
184
185config USB_F_RNDIS
186 tristate
187
188config USB_F_MASS_STORAGE
189 tristate
190
191config USB_F_FS
192 tristate
193
194config USB_F_UAC1
195 tristate
196
197config USB_F_UAC1_LEGACY
198 tristate
199
200config USB_F_UAC2
201 tristate
202
203config USB_F_UVC
204 tristate
205
206config USB_F_MIDI
207 tristate
208
209config USB_F_HID
210 tristate
211
212config USB_F_PRINTER
213 tristate
214
215config USB_F_TCM
216 tristate
217
218# this first set of drivers all depend on bulk-capable hardware.
219
220config USB_CONFIGFS
221 tristate "USB Gadget functions configurable through configfs"
222 select USB_LIBCOMPOSITE
223 help
224 A Linux USB "gadget" can be set up through configfs.
225 If this is the case, the USB functions (which from the host's
226 perspective are seen as interfaces) and configurations are
227 specified simply by creating appropriate directories in configfs.
228 Associating functions with configurations is done by creating
229 appropriate symbolic links.
230 For more information see Documentation/usb/gadget_configfs.txt.
231
232config USB_CONFIGFS_SERIAL
233 bool "Generic serial bulk in/out"
234 depends on USB_CONFIGFS
235 depends on TTY
236 select USB_U_SERIAL
237 select USB_F_SERIAL
238 help
239 The function talks to the Linux-USB generic serial driver.
240
241config USB_CONFIGFS_ACM
242 bool "Abstract Control Model (CDC ACM)"
243 depends on USB_CONFIGFS
244 depends on TTY
245 select USB_U_SERIAL
246 select USB_F_ACM
247 help
248 ACM serial link. This function can be used to interoperate with
249 MS-Windows hosts or with the Linux-USB "cdc-acm" driver.
250
251config USB_CONFIGFS_OBEX
252 bool "Object Exchange Model (CDC OBEX)"
253 depends on USB_CONFIGFS
254 depends on TTY
255 select USB_U_SERIAL
256 select USB_F_OBEX
257 help
258 You will need a user space OBEX server talking to /dev/ttyGS*,
259 since the kernel itself doesn't implement the OBEX protocol.
260
261config USB_CONFIGFS_NCM
262 bool "Network Control Model (CDC NCM)"
263 depends on USB_CONFIGFS
264 depends on NET
265 select USB_U_ETHER
266 select USB_F_NCM
267 help
268 NCM is an advanced protocol for Ethernet encapsulation, allows
269 grouping of several ethernet frames into one USB transfer and
270 different alignment possibilities.
271
272config USB_CONFIGFS_ECM
273 bool "Ethernet Control Model (CDC ECM)"
274 depends on USB_CONFIGFS
275 depends on NET
276 select USB_U_ETHER
277 select USB_F_ECM
278 help
279 The "Communication Device Class" (CDC) Ethernet Control Model.
280 That protocol is often avoided with pure Ethernet adapters, in
281 favor of simpler vendor-specific hardware, but is widely
282 supported by firmware for smart network devices.
283
284config USB_CONFIGFS_ECM_SUBSET
285 bool "Ethernet Control Model (CDC ECM) subset"
286 depends on USB_CONFIGFS
287 depends on NET
288 select USB_U_ETHER
289 select USB_F_SUBSET
290 help
291 On hardware that can't implement the full protocol,
292 a simple CDC subset is used, placing fewer demands on USB.
293
294config USB_CONFIGFS_RNDIS
295 bool "RNDIS"
296 depends on USB_CONFIGFS
297 depends on NET
298 select USB_U_ETHER
299 select USB_F_RNDIS
300 help
301 Microsoft Windows XP bundles the "Remote NDIS" (RNDIS) protocol,
302 and Microsoft provides redistributable binary RNDIS drivers for
303 older versions of Windows.
304
305 To make MS-Windows work with this, use Documentation/usb/linux.inf
306 as the "driver info file". For versions of MS-Windows older than
307 XP, you'll need to download drivers from Microsoft's website; a URL
308 is given in comments found in that info file.
309
310config USB_CONFIGFS_EEM
311 bool "Ethernet Emulation Model (EEM)"
312 depends on USB_CONFIGFS
313 depends on NET
314 select USB_U_ETHER
315 select USB_F_EEM
316 help
317 CDC EEM is a newer USB standard that is somewhat simpler than CDC ECM
318 and therefore can be supported by more hardware. Technically ECM and
319 EEM are designed for different applications. The ECM model extends
320 the network interface to the target (e.g. a USB cable modem), and the
321 EEM model is for mobile devices to communicate with hosts using
322 ethernet over USB. For Linux gadgets, however, the interface with
323 the host is the same (a usbX device), so the differences are minimal.
324
325config USB_CONFIGFS_PHONET
326 bool "Phonet protocol"
327 depends on USB_CONFIGFS
328 depends on NET
329 depends on PHONET
330 select USB_U_ETHER
331 select USB_F_PHONET
332 help
333 The Phonet protocol implementation for USB device.
334
335config USB_CONFIGFS_MASS_STORAGE
336 bool "Mass storage"
337 depends on USB_CONFIGFS
338 depends on BLOCK
339 select USB_F_MASS_STORAGE
340 help
341 The Mass Storage Gadget acts as a USB Mass Storage disk drive.
342 As its storage repository it can use a regular file or a block
343 device (in much the same way as the "loop" device driver),
344 specified as a module parameter or sysfs option.
345
346config USB_CONFIGFS_F_LB_SS
347 bool "Loopback and sourcesink function (for testing)"
348 depends on USB_CONFIGFS
349 select USB_F_SS_LB
350 help
351 Loopback function loops back a configurable number of transfers.
352 Sourcesink function either sinks and sources bulk data.
353 It also implements control requests, for "chapter 9" conformance.
354 Make this be the first driver you try using on top of any new
355 USB peripheral controller driver. Then you can use host-side
356 test software, like the "usbtest" driver, to put your hardware
357 and its driver through a basic set of functional tests.
358
359config USB_CONFIGFS_F_FS
360 bool "Function filesystem (FunctionFS)"
361 depends on USB_CONFIGFS
362 select USB_F_FS
363 help
364 The Function Filesystem (FunctionFS) lets one create USB
365 composite functions in user space in the same way GadgetFS
366 lets one create USB gadgets in user space. This allows creation
367 of composite gadgets such that some of the functions are
368 implemented in kernel space (for instance Ethernet, serial or
369 mass storage) and other are implemented in user space.
370
371config USB_CONFIGFS_F_UAC1
372 bool "Audio Class 1.0"
373 depends on USB_CONFIGFS
374 depends on SND
375 select USB_LIBCOMPOSITE
376 select SND_PCM
377 select USB_U_AUDIO
378 select USB_F_UAC1
379 help
380 This Audio function implements 1 AudioControl interface,
381 1 AudioStreaming Interface each for USB-OUT and USB-IN.
382 This driver doesn't expect any real Audio codec to be present
383 on the device - the audio streams are simply sinked to and
384 sourced from a virtual ALSA sound card created. The user-space
385 application may choose to do whatever it wants with the data
386 received from the USB Host and choose to provide whatever it
387 wants as audio data to the USB Host.
388
389config USB_CONFIGFS_F_UAC1_LEGACY
390 bool "Audio Class 1.0 (legacy implementation)"
391 depends on USB_CONFIGFS
392 depends on SND
393 select USB_LIBCOMPOSITE
394 select SND_PCM
395 select USB_F_UAC1_LEGACY
396 help
397 This Audio function implements 1 AudioControl interface,
398 1 AudioStreaming Interface each for USB-OUT and USB-IN.
399 This is a legacy driver and requires a real Audio codec
400 to be present on the device.
401
402config USB_CONFIGFS_F_UAC2
403 bool "Audio Class 2.0"
404 depends on USB_CONFIGFS
405 depends on SND
406 select USB_LIBCOMPOSITE
407 select SND_PCM
408 select USB_U_AUDIO
409 select USB_F_UAC2
410 help
411 This Audio function is compatible with USB Audio Class
412 specification 2.0. It implements 1 AudioControl interface,
413 1 AudioStreaming Interface each for USB-OUT and USB-IN.
414 This driver doesn't expect any real Audio codec to be present
415 on the device - the audio streams are simply sinked to and
416 sourced from a virtual ALSA sound card created. The user-space
417 application may choose to do whatever it wants with the data
418 received from the USB Host and choose to provide whatever it
419 wants as audio data to the USB Host.
420
421config USB_CONFIGFS_F_MIDI
422 bool "MIDI function"
423 depends on USB_CONFIGFS
424 depends on SND
425 select USB_LIBCOMPOSITE
426 select SND_RAWMIDI
427 select USB_F_MIDI
428 help
429 The MIDI Function acts as a USB Audio device, with one MIDI
430 input and one MIDI output. These MIDI jacks appear as
431 a sound "card" in the ALSA sound system. Other MIDI
432 connections can then be made on the gadget system, using
433 ALSA's aconnect utility etc.
434
435config USB_CONFIGFS_F_HID
436 bool "HID function"
437 depends on USB_CONFIGFS
438 select USB_F_HID
439 help
440 The HID function driver provides generic emulation of USB
441 Human Interface Devices (HID).
442
443 For more information, see Documentation/usb/gadget_hid.txt.
444
445config USB_CONFIGFS_F_UVC
446 bool "USB Webcam function"
447 depends on USB_CONFIGFS
448 depends on VIDEO_V4L2
449 depends on VIDEO_DEV
450 select VIDEOBUF2_VMALLOC
451 select USB_F_UVC
452 help
453 The Webcam function acts as a composite USB Audio and Video Class
454 device. It provides a userspace API to process UVC control requests
455 and stream video data to the host.
456
457config USB_CONFIGFS_F_PRINTER
458 bool "Printer function"
459 select USB_F_PRINTER
460 depends on USB_CONFIGFS
461 help
462 The Printer function channels data between the USB host and a
463 userspace program driving the print engine. The user space
464 program reads and writes the device file /dev/g_printer<X> to
465 receive or send printer data. It can use ioctl calls to
466 the device file to get or set printer status.
467
468 For more information, see Documentation/usb/gadget_printer.txt
469 which includes sample code for accessing the device file.
470
471config USB_CONFIGFS_F_TCM
472 bool "USB Gadget Target Fabric"
473 depends on TARGET_CORE
474 depends on USB_CONFIGFS
475 select USB_LIBCOMPOSITE
476 select USB_F_TCM
477 help
478 This fabric is a USB gadget component. Two USB protocols are
479 supported that is BBB or BOT (Bulk Only Transport) and UAS
480 (USB Attached SCSI). BOT is advertised on alternative
481 interface 0 (primary) and UAS is on alternative interface 1.
482 Both protocols can work on USB2.0 and USB3.0.
483 UAS utilizes the USB 3.0 feature called streams support.
484
485choice
486 tristate "USB Gadget precomposed configurations"
487 default USB_ETH
488 optional
489 help
490 A Linux "Gadget Driver" talks to the USB Peripheral Controller
491 driver through the abstract "gadget" API. Some other operating
492 systems call these "client" drivers, of which "class drivers"
493 are a subset (implementing a USB device class specification).
494 A gadget driver implements one or more USB functions using
495 the peripheral hardware.
496
497 Gadget drivers are hardware-neutral, or "platform independent",
498 except that they sometimes must understand quirks or limitations
499 of the particular controllers they work with. For example, when
500 a controller doesn't support alternate configurations or provide
501 enough of the right types of endpoints, the gadget driver might
502 not be able work with that controller, or might need to implement
503 a less common variant of a device class protocol.
504
505 The available choices each represent a single precomposed USB
506 gadget configuration. In the device model, each option contains
507 both the device instantiation as a child for a USB gadget
508 controller, and the relevant drivers for each function declared
509 by the device.
510
511source "drivers/usb/gadget/legacy/Kconfig"
512
513endchoice
514
515endif # USB_GADGET