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_MIDI2
212	tristate
213
214config USB_F_HID
215	tristate
216
217config USB_F_PRINTER
218	tristate
219
220config USB_F_TCM
221	tristate
222
223# this first set of drivers all depend on bulk-capable hardware.
224
225config USB_CONFIGFS
226	tristate "USB Gadget functions configurable through configfs"
227	select USB_LIBCOMPOSITE
228	help
229	  A Linux USB "gadget" can be set up through configfs.
230	  If this is the case, the USB functions (which from the host's
231	  perspective are seen as interfaces) and configurations are
232	  specified simply by creating appropriate directories in configfs.
233	  Associating functions with configurations is done by creating
234	  appropriate symbolic links.
235	  For more information see Documentation/usb/gadget_configfs.rst.
236
237config USB_CONFIGFS_SERIAL
238	bool "Generic serial bulk in/out"
239	depends on USB_CONFIGFS
240	depends on TTY
241	select USB_U_SERIAL
242	select USB_F_SERIAL
243	help
244	  The function talks to the Linux-USB generic serial driver.
245
246config USB_CONFIGFS_ACM
247	bool "Abstract Control Model (CDC ACM)"
248	depends on USB_CONFIGFS
249	depends on TTY
250	select USB_U_SERIAL
251	select USB_F_ACM
252	help
253	  ACM serial link.  This function can be used to interoperate with
254	  MS-Windows hosts or with the Linux-USB "cdc-acm" driver.
255
256config USB_CONFIGFS_OBEX
257	bool "Object Exchange Model (CDC OBEX)"
258	depends on USB_CONFIGFS
259	depends on TTY
260	select USB_U_SERIAL
261	select USB_F_OBEX
262	help
263	  You will need a user space OBEX server talking to /dev/ttyGS*,
264	  since the kernel itself doesn't implement the OBEX protocol.
265
266config USB_CONFIGFS_NCM
267	bool "Network Control Model (CDC NCM)"
268	depends on USB_CONFIGFS
269	depends on NET
270	select USB_U_ETHER
271	select USB_F_NCM
272	select CRC32
273	help
274	  NCM is an advanced protocol for Ethernet encapsulation, allows
275	  grouping of several ethernet frames into one USB transfer and
276	  different alignment possibilities.
277
278config USB_CONFIGFS_ECM
279	bool "Ethernet Control Model (CDC ECM)"
280	depends on USB_CONFIGFS
281	depends on NET
282	select USB_U_ETHER
283	select USB_F_ECM
284	help
285	  The "Communication Device Class" (CDC) Ethernet Control Model.
286	  That protocol is often avoided with pure Ethernet adapters, in
287	  favor of simpler vendor-specific hardware, but is widely
288	  supported by firmware for smart network devices.
289
290config USB_CONFIGFS_ECM_SUBSET
291	bool "Ethernet Control Model (CDC ECM) subset"
292	depends on USB_CONFIGFS
293	depends on NET
294	select USB_U_ETHER
295	select USB_F_SUBSET
296	help
297	  On hardware that can't implement the full protocol,
298	  a simple CDC subset is used, placing fewer demands on USB.
299
300config USB_CONFIGFS_RNDIS
301	bool "RNDIS"
302	depends on USB_CONFIGFS
303	depends on NET
304	select USB_U_ETHER
305	select USB_F_RNDIS
306	help
307	   Microsoft Windows XP bundles the "Remote NDIS" (RNDIS) protocol,
308	   and Microsoft provides redistributable binary RNDIS drivers for
309	   older versions of Windows.
310
311	   To make MS-Windows work with this, use Documentation/usb/linux.inf
312	   as the "driver info file".  For versions of MS-Windows older than
313	   XP, you'll need to download drivers from Microsoft's website; a URL
314	   is given in comments found in that info file.
315
316config USB_CONFIGFS_EEM
317	bool "Ethernet Emulation Model (EEM)"
318	depends on USB_CONFIGFS
319	depends on NET
320	select USB_U_ETHER
321	select USB_F_EEM
322	select CRC32
323	help
324	  CDC EEM is a newer USB standard that is somewhat simpler than CDC ECM
325	  and therefore can be supported by more hardware.  Technically ECM and
326	  EEM are designed for different applications.  The ECM model extends
327	  the network interface to the target (e.g. a USB cable modem), and the
328	  EEM model is for mobile devices to communicate with hosts using
329	  ethernet over USB.  For Linux gadgets, however, the interface with
330	  the host is the same (a usbX device), so the differences are minimal.
331
332config USB_CONFIGFS_PHONET
333	bool "Phonet protocol"
334	depends on USB_CONFIGFS
335	depends on NET
336	depends on PHONET
337	select USB_U_ETHER
338	select USB_F_PHONET
339	help
340	  The Phonet protocol implementation for USB device.
341
342config USB_CONFIGFS_MASS_STORAGE
343	bool "Mass storage"
344	depends on USB_CONFIGFS
345	depends on BLOCK
346	select USB_F_MASS_STORAGE
347	help
348	  The Mass Storage Gadget acts as a USB Mass Storage disk drive.
349	  As its storage repository it can use a regular file or a block
350	  device (in much the same way as the "loop" device driver),
351	  specified as a module parameter or sysfs option.
352
353config USB_CONFIGFS_F_LB_SS
354	bool "Loopback and sourcesink function (for testing)"
355	depends on USB_CONFIGFS
356	select USB_F_SS_LB
357	help
358	  Loopback function loops back a configurable number of transfers.
359	  Sourcesink function either sinks and sources bulk data.
360	  It also implements control requests, for "chapter 9" conformance.
361	  Make this be the first driver you try using on top of any new
362	  USB peripheral controller driver.  Then you can use host-side
363	  test software, like the "usbtest" driver, to put your hardware
364	  and its driver through a basic set of functional tests.
365
366config USB_CONFIGFS_F_FS
367	bool "Function filesystem (FunctionFS)"
368	depends on USB_CONFIGFS
369	select USB_F_FS
370	help
371	  The Function Filesystem (FunctionFS) lets one create USB
372	  composite functions in user space in the same way GadgetFS
373	  lets one create USB gadgets in user space.  This allows creation
374	  of composite gadgets such that some of the functions are
375	  implemented in kernel space (for instance Ethernet, serial or
376	  mass storage) and other are implemented in user space.
377
378config USB_CONFIGFS_F_UAC1
379	bool "Audio Class 1.0"
380	depends on USB_CONFIGFS
381	depends on SND
382	select USB_LIBCOMPOSITE
383	select SND_PCM
384	select USB_U_AUDIO
385	select USB_F_UAC1
386	help
387	  This Audio function implements 1 AudioControl interface,
388	  1 AudioStreaming Interface each for USB-OUT and USB-IN.
389	  This driver doesn't expect any real Audio codec to be present
390	  on the device - the audio streams are simply sinked to and
391	  sourced from a virtual ALSA sound card created. The user-space
392	  application may choose to do whatever it wants with the data
393	  received from the USB Host and choose to provide whatever it
394	  wants as audio data to the USB Host.
395
396config USB_CONFIGFS_F_UAC1_LEGACY
397	bool "Audio Class 1.0 (legacy implementation)"
398	depends on USB_CONFIGFS
399	depends on SND
400	select USB_LIBCOMPOSITE
401	select SND_PCM
402	select USB_F_UAC1_LEGACY
403	help
404	  This Audio function implements 1 AudioControl interface,
405	  1 AudioStreaming Interface each for USB-OUT and USB-IN.
406	  This is a legacy driver and requires a real Audio codec
407	  to be present on the device.
408
409config USB_CONFIGFS_F_UAC2
410	bool "Audio Class 2.0"
411	depends on USB_CONFIGFS
412	depends on SND
413	select USB_LIBCOMPOSITE
414	select SND_PCM
415	select USB_U_AUDIO
416	select USB_F_UAC2
417	help
418	  This Audio function is compatible with USB Audio Class
419	  specification 2.0. It implements 1 AudioControl interface,
420	  1 AudioStreaming Interface each for USB-OUT and USB-IN.
421	  This driver doesn't expect any real Audio codec to be present
422	  on the device - the audio streams are simply sinked to and
423	  sourced from a virtual ALSA sound card created. The user-space
424	  application may choose to do whatever it wants with the data
425	  received from the USB Host and choose to provide whatever it
426	  wants as audio data to the USB Host.
427
428config USB_CONFIGFS_F_MIDI
429	bool "MIDI function"
430	depends on USB_CONFIGFS
431	depends on SND
432	select USB_LIBCOMPOSITE
433	select SND_RAWMIDI
434	select USB_F_MIDI
435	help
436	  The MIDI Function acts as a USB Audio device, with one MIDI
437	  input and one MIDI output. These MIDI jacks appear as
438	  a sound "card" in the ALSA sound system. Other MIDI
439	  connections can then be made on the gadget system, using
440	  ALSA's aconnect utility etc.
441
442config USB_CONFIGFS_F_MIDI2
443	bool "MIDI 2.0 function"
444	depends on USB_CONFIGFS
445	depends on SND
446	select USB_LIBCOMPOSITE
447	select SND_UMP
448	select SND_UMP_LEGACY_RAWMIDI
449	select USB_F_MIDI2
450	help
451	  The MIDI 2.0 function driver provides the generic emulated
452	  USB MIDI 2.0 interface, looped back to ALSA UMP rawmidi
453	  device on the gadget host. It supports UMP 1.1 spec and
454	  responds UMP Stream messages for UMP Endpoint and Function
455	  Block information / configuration.
456
457config USB_CONFIGFS_F_HID
458	bool "HID function"
459	depends on USB_CONFIGFS
460	select USB_F_HID
461	help
462	  The HID function driver provides generic emulation of USB
463	  Human Interface Devices (HID).
464
465	  For more information, see Documentation/usb/gadget_hid.rst.
466
467config USB_CONFIGFS_F_UVC
468	bool "USB Webcam function"
469	depends on USB_CONFIGFS
470	depends on VIDEO_DEV
471	depends on VIDEO_DEV
472	select VIDEOBUF2_DMA_SG
473	select VIDEOBUF2_VMALLOC
474	select USB_F_UVC
475	help
476	  The Webcam function acts as a composite USB Audio and Video Class
477	  device. It provides a userspace API to process UVC control requests
478	  and stream video data to the host.
479
480config USB_CONFIGFS_F_PRINTER
481	bool "Printer function"
482	select USB_F_PRINTER
483	depends on USB_CONFIGFS
484	help
485	  The Printer function channels data between the USB host and a
486	  userspace program driving the print engine. The user space
487	  program reads and writes the device file /dev/g_printer<X> to
488	  receive or send printer data. It can use ioctl calls to
489	  the device file to get or set printer status.
490
491	  For more information, see Documentation/usb/gadget_printer.rst
492	  which includes sample code for accessing the device file.
493
494config USB_CONFIGFS_F_TCM
495	bool "USB Gadget Target Fabric"
496	depends on TARGET_CORE
497	depends on USB_CONFIGFS
498	select USB_LIBCOMPOSITE
499	select USB_F_TCM
500	help
501	  This fabric is a USB gadget component. Two USB protocols are
502	  supported that is BBB or BOT (Bulk Only Transport) and UAS
503	  (USB Attached SCSI). BOT is advertised on alternative
504	  interface 0 (primary) and UAS is on alternative interface 1.
505	  Both protocols can work on USB2.0 and USB3.0.
506	  UAS utilizes the USB 3.0 feature called streams support.
507
508source "drivers/usb/gadget/legacy/Kconfig"
509
510endif # USB_GADGET
511