xref: /openbmc/linux/drivers/usb/gadget/Kconfig (revision 293d5b43) 
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 DocBook 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_G_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_F_SERIAL
162	tristate
163
164config USB_F_OBEX
165	tristate
166
167config USB_F_NCM
168	tristate
169
170config USB_F_ECM
171	tristate
172
173config USB_F_PHONET
174	tristate
175
176config USB_F_EEM
177	tristate
178
179config USB_F_SUBSET
180	tristate
181
182config USB_F_RNDIS
183	tristate
184
185config USB_F_MASS_STORAGE
186	tristate
187
188config USB_F_FS
189	tristate
190
191config USB_F_UAC1
192	tristate
193
194config USB_F_UAC2
195	tristate
196
197config USB_F_UVC
198	tristate
199
200config USB_F_MIDI
201	tristate
202
203config USB_F_HID
204	tristate
205
206config USB_F_PRINTER
207	tristate
208
209config USB_F_TCM
210	tristate
211
212choice
213	tristate "USB Gadget Drivers"
214	default USB_ETH
215	help
216	  A Linux "Gadget Driver" talks to the USB Peripheral Controller
217	  driver through the abstract "gadget" API.  Some other operating
218	  systems call these "client" drivers, of which "class drivers"
219	  are a subset (implementing a USB device class specification).
220	  A gadget driver implements one or more USB functions using
221	  the peripheral hardware.
222
223	  Gadget drivers are hardware-neutral, or "platform independent",
224	  except that they sometimes must understand quirks or limitations
225	  of the particular controllers they work with.  For example, when
226	  a controller doesn't support alternate configurations or provide
227	  enough of the right types of endpoints, the gadget driver might
228	  not be able work with that controller, or might need to implement
229	  a less common variant of a device class protocol.
230
231# this first set of drivers all depend on bulk-capable hardware.
232
233config USB_CONFIGFS
234	tristate "USB functions configurable through configfs"
235	select USB_LIBCOMPOSITE
236	help
237	  A Linux USB "gadget" can be set up through configfs.
238	  If this is the case, the USB functions (which from the host's
239	  perspective are seen as interfaces) and configurations are
240	  specified simply by creating appropriate directories in configfs.
241	  Associating functions with configurations is done by creating
242	  appropriate symbolic links.
243	  For more information see Documentation/usb/gadget_configfs.txt.
244
245config USB_CONFIGFS_SERIAL
246	bool "Generic serial bulk in/out"
247	depends on USB_CONFIGFS
248	depends on TTY
249	select USB_U_SERIAL
250	select USB_F_SERIAL
251	help
252	  The function talks to the Linux-USB generic serial driver.
253
254config USB_CONFIGFS_ACM
255	bool "Abstract Control Model (CDC ACM)"
256	depends on USB_CONFIGFS
257	depends on TTY
258	select USB_U_SERIAL
259	select USB_F_ACM
260	help
261	  ACM serial link.  This function can be used to interoperate with
262	  MS-Windows hosts or with the Linux-USB "cdc-acm" driver.
263
264config USB_CONFIGFS_OBEX
265	bool "Object Exchange Model (CDC OBEX)"
266	depends on USB_CONFIGFS
267	depends on TTY
268	select USB_U_SERIAL
269	select USB_F_OBEX
270	help
271	  You will need a user space OBEX server talking to /dev/ttyGS*,
272	  since the kernel itself doesn't implement the OBEX protocol.
273
274config USB_CONFIGFS_NCM
275	bool "Network Control Model (CDC NCM)"
276	depends on USB_CONFIGFS
277	depends on NET
278	select USB_U_ETHER
279	select USB_F_NCM
280	help
281	  NCM is an advanced protocol for Ethernet encapsulation, allows
282	  grouping of several ethernet frames into one USB transfer and
283	  different alignment possibilities.
284
285config USB_CONFIGFS_ECM
286	bool "Ethernet Control Model (CDC ECM)"
287	depends on USB_CONFIGFS
288	depends on NET
289	select USB_U_ETHER
290	select USB_F_ECM
291	help
292	  The "Communication Device Class" (CDC) Ethernet Control Model.
293	  That protocol is often avoided with pure Ethernet adapters, in
294	  favor of simpler vendor-specific hardware, but is widely
295	  supported by firmware for smart network devices.
296
297config USB_CONFIGFS_ECM_SUBSET
298	bool "Ethernet Control Model (CDC ECM) subset"
299	depends on USB_CONFIGFS
300	depends on NET
301	select USB_U_ETHER
302	select USB_F_SUBSET
303	help
304	  On hardware that can't implement the full protocol,
305	  a simple CDC subset is used, placing fewer demands on USB.
306
307config USB_CONFIGFS_RNDIS
308	bool "RNDIS"
309	depends on USB_CONFIGFS
310	depends on NET
311	select USB_U_ETHER
312	select USB_F_RNDIS
313	help
314	   Microsoft Windows XP bundles the "Remote NDIS" (RNDIS) protocol,
315	   and Microsoft provides redistributable binary RNDIS drivers for
316	   older versions of Windows.
317
318	   To make MS-Windows work with this, use Documentation/usb/linux.inf
319	   as the "driver info file".  For versions of MS-Windows older than
320	   XP, you'll need to download drivers from Microsoft's website; a URL
321	   is given in comments found in that info file.
322
323config USB_CONFIGFS_EEM
324	bool "Ethernet Emulation Model (EEM)"
325	depends on USB_CONFIGFS
326	depends on NET
327	select USB_U_ETHER
328	select USB_F_EEM
329	help
330	  CDC EEM is a newer USB standard that is somewhat simpler than CDC ECM
331	  and therefore can be supported by more hardware.  Technically ECM and
332	  EEM are designed for different applications.  The ECM model extends
333	  the network interface to the target (e.g. a USB cable modem), and the
334	  EEM model is for mobile devices to communicate with hosts using
335	  ethernet over USB.  For Linux gadgets, however, the interface with
336	  the host is the same (a usbX device), so the differences are minimal.
337
338config USB_CONFIGFS_PHONET
339	bool "Phonet protocol"
340	depends on USB_CONFIGFS
341	depends on NET
342	depends on PHONET
343	select USB_U_ETHER
344	select USB_F_PHONET
345	help
346	  The Phonet protocol implementation for USB device.
347
348config USB_CONFIGFS_MASS_STORAGE
349	bool "Mass storage"
350	depends on USB_CONFIGFS
351	depends on BLOCK
352	select USB_F_MASS_STORAGE
353	help
354	  The Mass Storage Gadget acts as a USB Mass Storage disk drive.
355	  As its storage repository it can use a regular file or a block
356	  device (in much the same way as the "loop" device driver),
357	  specified as a module parameter or sysfs option.
358
359config USB_CONFIGFS_F_LB_SS
360	bool "Loopback and sourcesink function (for testing)"
361	depends on USB_CONFIGFS
362	select USB_F_SS_LB
363	help
364	  Loopback function loops back a configurable number of transfers.
365	  Sourcesink function either sinks and sources bulk data.
366	  It also implements control requests, for "chapter 9" conformance.
367	  Make this be the first driver you try using on top of any new
368	  USB peripheral controller driver.  Then you can use host-side
369	  test software, like the "usbtest" driver, to put your hardware
370	  and its driver through a basic set of functional tests.
371
372config USB_CONFIGFS_F_FS
373	bool "Function filesystem (FunctionFS)"
374	depends on USB_CONFIGFS
375	select USB_F_FS
376	help
377	  The Function Filesystem (FunctionFS) lets one create USB
378	  composite functions in user space in the same way GadgetFS
379	  lets one create USB gadgets in user space.  This allows creation
380	  of composite gadgets such that some of the functions are
381	  implemented in kernel space (for instance Ethernet, serial or
382	  mass storage) and other are implemented in user space.
383
384config USB_CONFIGFS_F_UAC1
385	bool "Audio Class 1.0"
386	depends on USB_CONFIGFS
387	depends on SND
388	select USB_LIBCOMPOSITE
389	select SND_PCM
390	select USB_F_UAC1
391	help
392	  This Audio function implements 1 AudioControl interface,
393	  1 AudioStreaming Interface each for USB-OUT and USB-IN.
394	  This driver requires a real Audio codec to be present
395	  on the device.
396
397config USB_CONFIGFS_F_UAC2
398	bool "Audio Class 2.0"
399	depends on USB_CONFIGFS
400	depends on SND
401	select USB_LIBCOMPOSITE
402	select SND_PCM
403	select USB_F_UAC2
404	help
405	  This Audio function is compatible with USB Audio Class
406	  specification 2.0. It implements 1 AudioControl interface,
407	  1 AudioStreaming Interface each for USB-OUT and USB-IN.
408	  This driver doesn't expect any real Audio codec to be present
409	  on the device - the audio streams are simply sinked to and
410	  sourced from a virtual ALSA sound card created. The user-space
411	  application may choose to do whatever it wants with the data
412	  received from the USB Host and choose to provide whatever it
413	  wants as audio data to the USB Host.
414
415config USB_CONFIGFS_F_MIDI
416	bool "MIDI function"
417	depends on USB_CONFIGFS
418	depends on SND
419	select USB_LIBCOMPOSITE
420	select SND_RAWMIDI
421	select USB_F_MIDI
422	help
423	  The MIDI Function acts as a USB Audio device, with one MIDI
424	  input and one MIDI output. These MIDI jacks appear as
425	  a sound "card" in the ALSA sound system. Other MIDI
426	  connections can then be made on the gadget system, using
427	  ALSA's aconnect utility etc.
428
429config USB_CONFIGFS_F_HID
430	bool "HID function"
431	depends on USB_CONFIGFS
432	select USB_F_HID
433	help
434	  The HID function driver provides generic emulation of USB
435	  Human Interface Devices (HID).
436
437	  For more information, see Documentation/usb/gadget_hid.txt.
438
439config USB_CONFIGFS_F_UVC
440	bool "USB Webcam function"
441	depends on USB_CONFIGFS
442	depends on VIDEO_DEV
443	select VIDEOBUF2_VMALLOC
444	select USB_F_UVC
445	help
446	  The Webcam function acts as a composite USB Audio and Video Class
447	  device. It provides a userspace API to process UVC control requests
448	  and stream video data to the host.
449
450config USB_CONFIGFS_F_PRINTER
451	bool "Printer function"
452	select USB_F_PRINTER
453	depends on USB_CONFIGFS
454	help
455	  The Printer function channels data between the USB host and a
456	  userspace program driving the print engine. The user space
457	  program reads and writes the device file /dev/g_printer<X> to
458	  receive or send printer data. It can use ioctl calls to
459	  the device file to get or set printer status.
460
461	  For more information, see Documentation/usb/gadget_printer.txt
462	  which includes sample code for accessing the device file.
463
464config USB_CONFIGFS_F_TCM
465	bool "USB Gadget Target Fabric"
466	depends on TARGET_CORE
467	depends on USB_CONFIGFS
468	select USB_LIBCOMPOSITE
469	select USB_F_TCM
470	help
471	  This fabric is a USB gadget component. Two USB protocols are
472	  supported that is BBB or BOT (Bulk Only Transport) and UAS
473	  (USB Attached SCSI). BOT is advertised on alternative
474	  interface 0 (primary) and UAS is on alternative interface 1.
475	  Both protocols can work on USB2.0 and USB3.0.
476	  UAS utilizes the USB 3.0 feature called streams support.
477
478source "drivers/usb/gadget/legacy/Kconfig"
479
480endchoice
481
482endif # USB_GADGET
483