xref: /openbmc/linux/drivers/usb/gadget/Kconfig (revision ba61bb17)
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
516