xref: /openbmc/linux/drivers/usb/gadget/Kconfig (revision d47a97bd) 
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	select UVC_COMMON
207
208config USB_F_MIDI
209	tristate
210
211config USB_F_HID
212	tristate
213
214config USB_F_PRINTER
215	tristate
216
217config USB_F_TCM
218	tristate
219
220# this first set of drivers all depend on bulk-capable hardware.
221
222config USB_CONFIGFS
223	tristate "USB Gadget functions configurable through configfs"
224	select USB_LIBCOMPOSITE
225	help
226	  A Linux USB "gadget" can be set up through configfs.
227	  If this is the case, the USB functions (which from the host's
228	  perspective are seen as interfaces) and configurations are
229	  specified simply by creating appropriate directories in configfs.
230	  Associating functions with configurations is done by creating
231	  appropriate symbolic links.
232	  For more information see Documentation/usb/gadget_configfs.rst.
233
234config USB_CONFIGFS_SERIAL
235	bool "Generic serial bulk in/out"
236	depends on USB_CONFIGFS
237	depends on TTY
238	select USB_U_SERIAL
239	select USB_F_SERIAL
240	help
241	  The function talks to the Linux-USB generic serial driver.
242
243config USB_CONFIGFS_ACM
244	bool "Abstract Control Model (CDC ACM)"
245	depends on USB_CONFIGFS
246	depends on TTY
247	select USB_U_SERIAL
248	select USB_F_ACM
249	help
250	  ACM serial link.  This function can be used to interoperate with
251	  MS-Windows hosts or with the Linux-USB "cdc-acm" driver.
252
253config USB_CONFIGFS_OBEX
254	bool "Object Exchange Model (CDC OBEX)"
255	depends on USB_CONFIGFS
256	depends on TTY
257	select USB_U_SERIAL
258	select USB_F_OBEX
259	help
260	  You will need a user space OBEX server talking to /dev/ttyGS*,
261	  since the kernel itself doesn't implement the OBEX protocol.
262
263config USB_CONFIGFS_NCM
264	bool "Network Control Model (CDC NCM)"
265	depends on USB_CONFIGFS
266	depends on NET
267	select USB_U_ETHER
268	select USB_F_NCM
269	select CRC32
270	help
271	  NCM is an advanced protocol for Ethernet encapsulation, allows
272	  grouping of several ethernet frames into one USB transfer and
273	  different alignment possibilities.
274
275config USB_CONFIGFS_ECM
276	bool "Ethernet Control Model (CDC ECM)"
277	depends on USB_CONFIGFS
278	depends on NET
279	select USB_U_ETHER
280	select USB_F_ECM
281	help
282	  The "Communication Device Class" (CDC) Ethernet Control Model.
283	  That protocol is often avoided with pure Ethernet adapters, in
284	  favor of simpler vendor-specific hardware, but is widely
285	  supported by firmware for smart network devices.
286
287config USB_CONFIGFS_ECM_SUBSET
288	bool "Ethernet Control Model (CDC ECM) subset"
289	depends on USB_CONFIGFS
290	depends on NET
291	select USB_U_ETHER
292	select USB_F_SUBSET
293	help
294	  On hardware that can't implement the full protocol,
295	  a simple CDC subset is used, placing fewer demands on USB.
296
297config USB_CONFIGFS_RNDIS
298	bool "RNDIS"
299	depends on USB_CONFIGFS
300	depends on NET
301	select USB_U_ETHER
302	select USB_F_RNDIS
303	help
304	   Microsoft Windows XP bundles the "Remote NDIS" (RNDIS) protocol,
305	   and Microsoft provides redistributable binary RNDIS drivers for
306	   older versions of Windows.
307
308	   To make MS-Windows work with this, use Documentation/usb/linux.inf
309	   as the "driver info file".  For versions of MS-Windows older than
310	   XP, you'll need to download drivers from Microsoft's website; a URL
311	   is given in comments found in that info file.
312
313config USB_CONFIGFS_EEM
314	bool "Ethernet Emulation Model (EEM)"
315	depends on USB_CONFIGFS
316	depends on NET
317	select USB_U_ETHER
318	select USB_F_EEM
319	select CRC32
320	help
321	  CDC EEM is a newer USB standard that is somewhat simpler than CDC ECM
322	  and therefore can be supported by more hardware.  Technically ECM and
323	  EEM are designed for different applications.  The ECM model extends
324	  the network interface to the target (e.g. a USB cable modem), and the
325	  EEM model is for mobile devices to communicate with hosts using
326	  ethernet over USB.  For Linux gadgets, however, the interface with
327	  the host is the same (a usbX device), so the differences are minimal.
328
329config USB_CONFIGFS_PHONET
330	bool "Phonet protocol"
331	depends on USB_CONFIGFS
332	depends on NET
333	depends on PHONET
334	select USB_U_ETHER
335	select USB_F_PHONET
336	help
337	  The Phonet protocol implementation for USB device.
338
339config USB_CONFIGFS_MASS_STORAGE
340	bool "Mass storage"
341	depends on USB_CONFIGFS
342	depends on BLOCK
343	select USB_F_MASS_STORAGE
344	help
345	  The Mass Storage Gadget acts as a USB Mass Storage disk drive.
346	  As its storage repository it can use a regular file or a block
347	  device (in much the same way as the "loop" device driver),
348	  specified as a module parameter or sysfs option.
349
350config USB_CONFIGFS_F_LB_SS
351	bool "Loopback and sourcesink function (for testing)"
352	depends on USB_CONFIGFS
353	select USB_F_SS_LB
354	help
355	  Loopback function loops back a configurable number of transfers.
356	  Sourcesink function either sinks and sources bulk data.
357	  It also implements control requests, for "chapter 9" conformance.
358	  Make this be the first driver you try using on top of any new
359	  USB peripheral controller driver.  Then you can use host-side
360	  test software, like the "usbtest" driver, to put your hardware
361	  and its driver through a basic set of functional tests.
362
363config USB_CONFIGFS_F_FS
364	bool "Function filesystem (FunctionFS)"
365	depends on USB_CONFIGFS
366	select USB_F_FS
367	help
368	  The Function Filesystem (FunctionFS) lets one create USB
369	  composite functions in user space in the same way GadgetFS
370	  lets one create USB gadgets in user space.  This allows creation
371	  of composite gadgets such that some of the functions are
372	  implemented in kernel space (for instance Ethernet, serial or
373	  mass storage) and other are implemented in user space.
374
375config USB_CONFIGFS_F_UAC1
376	bool "Audio Class 1.0"
377	depends on USB_CONFIGFS
378	depends on SND
379	select USB_LIBCOMPOSITE
380	select SND_PCM
381	select USB_U_AUDIO
382	select USB_F_UAC1
383	help
384	  This Audio function implements 1 AudioControl interface,
385	  1 AudioStreaming Interface each for USB-OUT and USB-IN.
386	  This driver doesn't expect any real Audio codec to be present
387	  on the device - the audio streams are simply sinked to and
388	  sourced from a virtual ALSA sound card created. The user-space
389	  application may choose to do whatever it wants with the data
390	  received from the USB Host and choose to provide whatever it
391	  wants as audio data to the USB Host.
392
393config USB_CONFIGFS_F_UAC1_LEGACY
394	bool "Audio Class 1.0 (legacy implementation)"
395	depends on USB_CONFIGFS
396	depends on SND
397	select USB_LIBCOMPOSITE
398	select SND_PCM
399	select USB_F_UAC1_LEGACY
400	help
401	  This Audio function implements 1 AudioControl interface,
402	  1 AudioStreaming Interface each for USB-OUT and USB-IN.
403	  This is a legacy driver and requires a real Audio codec
404	  to be present on the device.
405
406config USB_CONFIGFS_F_UAC2
407	bool "Audio Class 2.0"
408	depends on USB_CONFIGFS
409	depends on SND
410	select USB_LIBCOMPOSITE
411	select SND_PCM
412	select USB_U_AUDIO
413	select USB_F_UAC2
414	help
415	  This Audio function is compatible with USB Audio Class
416	  specification 2.0. It implements 1 AudioControl interface,
417	  1 AudioStreaming Interface each for USB-OUT and USB-IN.
418	  This driver doesn't expect any real Audio codec to be present
419	  on the device - the audio streams are simply sinked to and
420	  sourced from a virtual ALSA sound card created. The user-space
421	  application may choose to do whatever it wants with the data
422	  received from the USB Host and choose to provide whatever it
423	  wants as audio data to the USB Host.
424
425config USB_CONFIGFS_F_MIDI
426	bool "MIDI function"
427	depends on USB_CONFIGFS
428	depends on SND
429	select USB_LIBCOMPOSITE
430	select SND_RAWMIDI
431	select USB_F_MIDI
432	help
433	  The MIDI Function acts as a USB Audio device, with one MIDI
434	  input and one MIDI output. These MIDI jacks appear as
435	  a sound "card" in the ALSA sound system. Other MIDI
436	  connections can then be made on the gadget system, using
437	  ALSA's aconnect utility etc.
438
439config USB_CONFIGFS_F_HID
440	bool "HID function"
441	depends on USB_CONFIGFS
442	select USB_F_HID
443	help
444	  The HID function driver provides generic emulation of USB
445	  Human Interface Devices (HID).
446
447	  For more information, see Documentation/usb/gadget_hid.rst.
448
449config USB_CONFIGFS_F_UVC
450	bool "USB Webcam function"
451	depends on USB_CONFIGFS
452	depends on VIDEO_DEV
453	depends on VIDEO_DEV
454	select VIDEOBUF2_DMA_SG
455	select VIDEOBUF2_VMALLOC
456	select USB_F_UVC
457	help
458	  The Webcam function acts as a composite USB Audio and Video Class
459	  device. It provides a userspace API to process UVC control requests
460	  and stream video data to the host.
461
462config USB_CONFIGFS_F_PRINTER
463	bool "Printer function"
464	select USB_F_PRINTER
465	depends on USB_CONFIGFS
466	help
467	  The Printer function channels data between the USB host and a
468	  userspace program driving the print engine. The user space
469	  program reads and writes the device file /dev/g_printer<X> to
470	  receive or send printer data. It can use ioctl calls to
471	  the device file to get or set printer status.
472
473	  For more information, see Documentation/usb/gadget_printer.rst
474	  which includes sample code for accessing the device file.
475
476config USB_CONFIGFS_F_TCM
477	bool "USB Gadget Target Fabric"
478	depends on TARGET_CORE
479	depends on USB_CONFIGFS
480	select USB_LIBCOMPOSITE
481	select USB_F_TCM
482	help
483	  This fabric is a USB gadget component. Two USB protocols are
484	  supported that is BBB or BOT (Bulk Only Transport) and UAS
485	  (USB Attached SCSI). BOT is advertised on alternative
486	  interface 0 (primary) and UAS is on alternative interface 1.
487	  Both protocols can work on USB2.0 and USB3.0.
488	  UAS utilizes the USB 3.0 feature called streams support.
489
490source "drivers/usb/gadget/legacy/Kconfig"
491
492endif # USB_GADGET
493