xref: /openbmc/linux/drivers/usb/gadget/Kconfig (revision c4f7ac64) 
1# SPDX-License-Identifier: GPL-2.0
2#
3# USB Gadget support on a system involves
4#    (a) a peripheral controller, and
5#    (b) the gadget driver using it.
6#
7# NOTE:  Gadget support ** DOES NOT ** depend on host-side CONFIG_USB !!
8#
9#  - Host systems (like PCs) need CONFIG_USB (with "A" jacks).
10#  - Peripherals (like PDAs) need CONFIG_USB_GADGET (with "B" jacks).
11#  - Some systems have both kinds of controllers.
12#
13# With help from a special transceiver and a "Mini-AB" jack, systems with
14# both kinds of controller can also support "USB On-the-Go" (CONFIG_USB_OTG).
15#
16
17menuconfig USB_GADGET
18	tristate "USB Gadget Support"
19	select USB_COMMON
20	select NLS
21	help
22	   USB is a host/device protocol, organized with one host (such as a
23	   PC) controlling up to 127 peripheral devices.
24	   The USB hardware is asymmetric, which makes it easier to set up:
25	   you can't connect a "to-the-host" connector to a peripheral.
26
27	   Linux can run in the host, or in the peripheral.  In both cases
28	   you need a low level bus controller driver, and some software
29	   talking to it.  Peripheral controllers are often discrete silicon,
30	   or are integrated with the CPU in a microcontroller.  The more
31	   familiar host side controllers have names like "EHCI", "OHCI",
32	   or "UHCI", and are usually integrated into southbridges on PC
33	   motherboards.
34
35	   Enable this configuration option if you want to run Linux inside
36	   a USB peripheral device.  Configure one hardware driver for your
37	   peripheral/device side bus controller, and a "gadget driver" for
38	   your peripheral protocol.  (If you use modular gadget drivers,
39	   you may configure more than one.)
40
41	   If in doubt, say "N" and don't enable these drivers; most people
42	   don't have this kind of hardware (except maybe inside Linux PDAs).
43
44	   For more information, see <http://www.linux-usb.org/gadget> and
45	   the kernel documentation for this API.
46
47if USB_GADGET
48
49config USB_GADGET_DEBUG
50	bool "Debugging messages (DEVELOPMENT)"
51	depends on DEBUG_KERNEL
52	help
53	   Many controller and gadget drivers will print some debugging
54	   messages if you use this option to ask for those messages.
55
56	   Avoid enabling these messages, even if you're actively
57	   debugging such a driver.  Many drivers will emit so many
58	   messages that the driver timings are affected, which will
59	   either create new failure modes or remove the one you're
60	   trying to track down.  Never enable these messages for a
61	   production build.
62
63config USB_GADGET_VERBOSE
64	bool "Verbose debugging Messages (DEVELOPMENT)"
65	depends on USB_GADGET_DEBUG
66	help
67	   Many controller and gadget drivers will print verbose debugging
68	   messages if you use this option to ask for those messages.
69
70	   Avoid enabling these messages, even if you're actively
71	   debugging such a driver.  Many drivers will emit so many
72	   messages that the driver timings are affected, which will
73	   either create new failure modes or remove the one you're
74	   trying to track down.  Never enable these messages for a
75	   production build.
76
77config USB_GADGET_DEBUG_FILES
78	bool "Debugging information files (DEVELOPMENT)"
79	depends on PROC_FS
80	help
81	   Some of the drivers in the "gadget" framework can expose
82	   debugging information in files such as /proc/driver/udc
83	   (for a peripheral controller).  The information in these
84	   files may help when you're troubleshooting or bringing up a
85	   driver on a new board.   Enable these files by choosing "Y"
86	   here.  If in doubt, or to conserve kernel memory, say "N".
87
88config USB_GADGET_DEBUG_FS
89	bool "Debugging information files in debugfs (DEVELOPMENT)"
90	depends on DEBUG_FS
91	help
92	   Some of the drivers in the "gadget" framework can expose
93	   debugging information in files under /sys/kernel/debug/.
94	   The information in these files may help when you're
95	   troubleshooting or bringing up a driver on a new board.
96	   Enable these files by choosing "Y" here.  If in doubt, or
97	   to conserve kernel memory, say "N".
98
99config USB_GADGET_VBUS_DRAW
100	int "Maximum VBUS Power usage (2-500 mA)"
101	range 2 500
102	default 2
103	help
104	   Some devices need to draw power from USB when they are
105	   configured, perhaps to operate circuitry or to recharge
106	   batteries.  This is in addition to any local power supply,
107	   such as an AC adapter or batteries.
108
109	   Enter the maximum power your device draws through USB, in
110	   milliAmperes.  The permitted range of values is 2 - 500 mA;
111	   0 mA would be legal, but can make some hosts misbehave.
112
113	   This value will be used except for system-specific gadget
114	   drivers that have more specific information.
115
116config USB_GADGET_STORAGE_NUM_BUFFERS
117	int "Number of storage pipeline buffers"
118	range 2 256
119	default 2
120	help
121	   Usually 2 buffers are enough to establish a good buffering
122	   pipeline. The number may be increased in order to compensate
123	   for a bursty VFS behaviour. For instance there may be CPU wake up
124	   latencies that makes the VFS to appear bursty in a system with
125	   an CPU on-demand governor. Especially if DMA is doing IO to
126	   offload the CPU. In this case the CPU will go into power
127	   save often and spin up occasionally to move data within VFS.
128	   If selecting USB_GADGET_DEBUG_FILES this value may be set by
129	   a module parameter as well.
130	   If unsure, say 2.
131
132config U_SERIAL_CONSOLE
133	bool "Serial gadget console support"
134	depends on USB_U_SERIAL
135	help
136	   It supports the serial gadget can be used as a console.
137
138source "drivers/usb/gadget/udc/Kconfig"
139
140#
141# USB Gadget Drivers
142#
143
144# composite based drivers
145config USB_LIBCOMPOSITE
146	tristate
147	select CONFIGFS_FS
148	depends on USB_GADGET
149
150config USB_F_ACM
151	tristate
152
153config USB_F_SS_LB
154	tristate
155
156config USB_U_SERIAL
157	tristate
158
159config USB_U_ETHER
160	tristate
161
162config USB_U_AUDIO
163	tristate
164
165config USB_F_SERIAL
166	tristate
167
168config USB_F_OBEX
169	tristate
170
171config USB_F_NCM
172	tristate
173
174config USB_F_ECM
175	tristate
176
177config USB_F_PHONET
178	tristate
179
180config USB_F_EEM
181	tristate
182
183config USB_F_SUBSET
184	tristate
185
186config USB_F_RNDIS
187	tristate
188
189config USB_F_MASS_STORAGE
190	tristate
191
192config USB_F_FS
193	tristate
194
195config USB_F_UAC1
196	tristate
197
198config USB_F_UAC1_LEGACY
199	tristate
200
201config USB_F_UAC2
202	tristate
203
204config USB_F_UVC
205	tristate
206
207config USB_F_MIDI
208	tristate
209
210config USB_F_HID
211	tristate
212
213config USB_F_PRINTER
214	tristate
215
216config USB_F_TCM
217	tristate
218
219# this first set of drivers all depend on bulk-capable hardware.
220
221config USB_CONFIGFS
222	tristate "USB Gadget functions configurable through configfs"
223	select USB_LIBCOMPOSITE
224	help
225	  A Linux USB "gadget" can be set up through configfs.
226	  If this is the case, the USB functions (which from the host's
227	  perspective are seen as interfaces) and configurations are
228	  specified simply by creating appropriate directories in configfs.
229	  Associating functions with configurations is done by creating
230	  appropriate symbolic links.
231	  For more information see Documentation/usb/gadget_configfs.rst.
232
233config USB_CONFIGFS_SERIAL
234	bool "Generic serial bulk in/out"
235	depends on USB_CONFIGFS
236	depends on TTY
237	select USB_U_SERIAL
238	select USB_F_SERIAL
239	help
240	  The function talks to the Linux-USB generic serial driver.
241
242config USB_CONFIGFS_ACM
243	bool "Abstract Control Model (CDC ACM)"
244	depends on USB_CONFIGFS
245	depends on TTY
246	select USB_U_SERIAL
247	select USB_F_ACM
248	help
249	  ACM serial link.  This function can be used to interoperate with
250	  MS-Windows hosts or with the Linux-USB "cdc-acm" driver.
251
252config USB_CONFIGFS_OBEX
253	bool "Object Exchange Model (CDC OBEX)"
254	depends on USB_CONFIGFS
255	depends on TTY
256	select USB_U_SERIAL
257	select USB_F_OBEX
258	help
259	  You will need a user space OBEX server talking to /dev/ttyGS*,
260	  since the kernel itself doesn't implement the OBEX protocol.
261
262config USB_CONFIGFS_NCM
263	bool "Network Control Model (CDC NCM)"
264	depends on USB_CONFIGFS
265	depends on NET
266	select USB_U_ETHER
267	select USB_F_NCM
268	select CRC32
269	help
270	  NCM is an advanced protocol for Ethernet encapsulation, allows
271	  grouping of several ethernet frames into one USB transfer and
272	  different alignment possibilities.
273
274config USB_CONFIGFS_ECM
275	bool "Ethernet Control Model (CDC ECM)"
276	depends on USB_CONFIGFS
277	depends on NET
278	select USB_U_ETHER
279	select USB_F_ECM
280	help
281	  The "Communication Device Class" (CDC) Ethernet Control Model.
282	  That protocol is often avoided with pure Ethernet adapters, in
283	  favor of simpler vendor-specific hardware, but is widely
284	  supported by firmware for smart network devices.
285
286config USB_CONFIGFS_ECM_SUBSET
287	bool "Ethernet Control Model (CDC ECM) subset"
288	depends on USB_CONFIGFS
289	depends on NET
290	select USB_U_ETHER
291	select USB_F_SUBSET
292	help
293	  On hardware that can't implement the full protocol,
294	  a simple CDC subset is used, placing fewer demands on USB.
295
296config USB_CONFIGFS_RNDIS
297	bool "RNDIS"
298	depends on USB_CONFIGFS
299	depends on NET
300	select USB_U_ETHER
301	select USB_F_RNDIS
302	help
303	   Microsoft Windows XP bundles the "Remote NDIS" (RNDIS) protocol,
304	   and Microsoft provides redistributable binary RNDIS drivers for
305	   older versions of Windows.
306
307	   To make MS-Windows work with this, use Documentation/usb/linux.inf
308	   as the "driver info file".  For versions of MS-Windows older than
309	   XP, you'll need to download drivers from Microsoft's website; a URL
310	   is given in comments found in that info file.
311
312config USB_CONFIGFS_EEM
313	bool "Ethernet Emulation Model (EEM)"
314	depends on USB_CONFIGFS
315	depends on NET
316	select USB_U_ETHER
317	select USB_F_EEM
318	select CRC32
319	help
320	  CDC EEM is a newer USB standard that is somewhat simpler than CDC ECM
321	  and therefore can be supported by more hardware.  Technically ECM and
322	  EEM are designed for different applications.  The ECM model extends
323	  the network interface to the target (e.g. a USB cable modem), and the
324	  EEM model is for mobile devices to communicate with hosts using
325	  ethernet over USB.  For Linux gadgets, however, the interface with
326	  the host is the same (a usbX device), so the differences are minimal.
327
328config USB_CONFIGFS_PHONET
329	bool "Phonet protocol"
330	depends on USB_CONFIGFS
331	depends on NET
332	depends on PHONET
333	select USB_U_ETHER
334	select USB_F_PHONET
335	help
336	  The Phonet protocol implementation for USB device.
337
338config USB_CONFIGFS_MASS_STORAGE
339	bool "Mass storage"
340	depends on USB_CONFIGFS
341	depends on BLOCK
342	select USB_F_MASS_STORAGE
343	help
344	  The Mass Storage Gadget acts as a USB Mass Storage disk drive.
345	  As its storage repository it can use a regular file or a block
346	  device (in much the same way as the "loop" device driver),
347	  specified as a module parameter or sysfs option.
348
349config USB_CONFIGFS_F_LB_SS
350	bool "Loopback and sourcesink function (for testing)"
351	depends on USB_CONFIGFS
352	select USB_F_SS_LB
353	help
354	  Loopback function loops back a configurable number of transfers.
355	  Sourcesink function either sinks and sources bulk data.
356	  It also implements control requests, for "chapter 9" conformance.
357	  Make this be the first driver you try using on top of any new
358	  USB peripheral controller driver.  Then you can use host-side
359	  test software, like the "usbtest" driver, to put your hardware
360	  and its driver through a basic set of functional tests.
361
362config USB_CONFIGFS_F_FS
363	bool "Function filesystem (FunctionFS)"
364	depends on USB_CONFIGFS
365	select USB_F_FS
366	help
367	  The Function Filesystem (FunctionFS) lets one create USB
368	  composite functions in user space in the same way GadgetFS
369	  lets one create USB gadgets in user space.  This allows creation
370	  of composite gadgets such that some of the functions are
371	  implemented in kernel space (for instance Ethernet, serial or
372	  mass storage) and other are implemented in user space.
373
374config USB_CONFIGFS_F_UAC1
375	bool "Audio Class 1.0"
376	depends on USB_CONFIGFS
377	depends on SND
378	select USB_LIBCOMPOSITE
379	select SND_PCM
380	select USB_U_AUDIO
381	select USB_F_UAC1
382	help
383	  This Audio function implements 1 AudioControl interface,
384	  1 AudioStreaming Interface each for USB-OUT and USB-IN.
385	  This driver doesn't expect any real Audio codec to be present
386	  on the device - the audio streams are simply sinked to and
387	  sourced from a virtual ALSA sound card created. The user-space
388	  application may choose to do whatever it wants with the data
389	  received from the USB Host and choose to provide whatever it
390	  wants as audio data to the USB Host.
391
392config USB_CONFIGFS_F_UAC1_LEGACY
393	bool "Audio Class 1.0 (legacy implementation)"
394	depends on USB_CONFIGFS
395	depends on SND
396	select USB_LIBCOMPOSITE
397	select SND_PCM
398	select USB_F_UAC1_LEGACY
399	help
400	  This Audio function implements 1 AudioControl interface,
401	  1 AudioStreaming Interface each for USB-OUT and USB-IN.
402	  This is a legacy driver and requires a real Audio codec
403	  to be present on the device.
404
405config USB_CONFIGFS_F_UAC2
406	bool "Audio Class 2.0"
407	depends on USB_CONFIGFS
408	depends on SND
409	select USB_LIBCOMPOSITE
410	select SND_PCM
411	select USB_U_AUDIO
412	select USB_F_UAC2
413	help
414	  This Audio function is compatible with USB Audio Class
415	  specification 2.0. It implements 1 AudioControl interface,
416	  1 AudioStreaming Interface each for USB-OUT and USB-IN.
417	  This driver doesn't expect any real Audio codec to be present
418	  on the device - the audio streams are simply sinked to and
419	  sourced from a virtual ALSA sound card created. The user-space
420	  application may choose to do whatever it wants with the data
421	  received from the USB Host and choose to provide whatever it
422	  wants as audio data to the USB Host.
423
424config USB_CONFIGFS_F_MIDI
425	bool "MIDI function"
426	depends on USB_CONFIGFS
427	depends on SND
428	select USB_LIBCOMPOSITE
429	select SND_RAWMIDI
430	select USB_F_MIDI
431	help
432	  The MIDI Function acts as a USB Audio device, with one MIDI
433	  input and one MIDI output. These MIDI jacks appear as
434	  a sound "card" in the ALSA sound system. Other MIDI
435	  connections can then be made on the gadget system, using
436	  ALSA's aconnect utility etc.
437
438config USB_CONFIGFS_F_HID
439	bool "HID function"
440	depends on USB_CONFIGFS
441	select USB_F_HID
442	help
443	  The HID function driver provides generic emulation of USB
444	  Human Interface Devices (HID).
445
446	  For more information, see Documentation/usb/gadget_hid.rst.
447
448config USB_CONFIGFS_F_UVC
449	bool "USB Webcam function"
450	depends on USB_CONFIGFS
451	depends on VIDEO_V4L2
452	depends on VIDEO_DEV
453	select VIDEOBUF2_VMALLOC
454	select USB_F_UVC
455	help
456	  The Webcam function acts as a composite USB Audio and Video Class
457	  device. It provides a userspace API to process UVC control requests
458	  and stream video data to the host.
459
460config USB_CONFIGFS_F_PRINTER
461	bool "Printer function"
462	select USB_F_PRINTER
463	depends on USB_CONFIGFS
464	help
465	  The Printer function channels data between the USB host and a
466	  userspace program driving the print engine. The user space
467	  program reads and writes the device file /dev/g_printer<X> to
468	  receive or send printer data. It can use ioctl calls to
469	  the device file to get or set printer status.
470
471	  For more information, see Documentation/usb/gadget_printer.rst
472	  which includes sample code for accessing the device file.
473
474config USB_CONFIGFS_F_TCM
475	bool "USB Gadget Target Fabric"
476	depends on TARGET_CORE
477	depends on USB_CONFIGFS
478	select USB_LIBCOMPOSITE
479	select USB_F_TCM
480	help
481	  This fabric is a USB gadget component. Two USB protocols are
482	  supported that is BBB or BOT (Bulk Only Transport) and UAS
483	  (USB Attached SCSI). BOT is advertised on alternative
484	  interface 0 (primary) and UAS is on alternative interface 1.
485	  Both protocols can work on USB2.0 and USB3.0.
486	  UAS utilizes the USB 3.0 feature called streams support.
487
488source "drivers/usb/gadget/legacy/Kconfig"
489
490endif # USB_GADGET
491