xref: /openbmc/linux/drivers/usb/gadget/Kconfig (revision c0c74acb) 
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
212# this first set of drivers all depend on bulk-capable hardware.
213
214config USB_CONFIGFS
215	tristate "USB functions configurable through configfs"
216	select USB_LIBCOMPOSITE
217	help
218	  A Linux USB "gadget" can be set up through configfs.
219	  If this is the case, the USB functions (which from the host's
220	  perspective are seen as interfaces) and configurations are
221	  specified simply by creating appropriate directories in configfs.
222	  Associating functions with configurations is done by creating
223	  appropriate symbolic links.
224	  For more information see Documentation/usb/gadget_configfs.txt.
225
226config USB_CONFIGFS_SERIAL
227	bool "Generic serial bulk in/out"
228	depends on USB_CONFIGFS
229	depends on TTY
230	select USB_U_SERIAL
231	select USB_F_SERIAL
232	help
233	  The function talks to the Linux-USB generic serial driver.
234
235config USB_CONFIGFS_ACM
236	bool "Abstract Control Model (CDC ACM)"
237	depends on USB_CONFIGFS
238	depends on TTY
239	select USB_U_SERIAL
240	select USB_F_ACM
241	help
242	  ACM serial link.  This function can be used to interoperate with
243	  MS-Windows hosts or with the Linux-USB "cdc-acm" driver.
244
245config USB_CONFIGFS_OBEX
246	bool "Object Exchange Model (CDC OBEX)"
247	depends on USB_CONFIGFS
248	depends on TTY
249	select USB_U_SERIAL
250	select USB_F_OBEX
251	help
252	  You will need a user space OBEX server talking to /dev/ttyGS*,
253	  since the kernel itself doesn't implement the OBEX protocol.
254
255config USB_CONFIGFS_NCM
256	bool "Network Control Model (CDC NCM)"
257	depends on USB_CONFIGFS
258	depends on NET
259	select USB_U_ETHER
260	select USB_F_NCM
261	help
262	  NCM is an advanced protocol for Ethernet encapsulation, allows
263	  grouping of several ethernet frames into one USB transfer and
264	  different alignment possibilities.
265
266config USB_CONFIGFS_ECM
267	bool "Ethernet Control Model (CDC ECM)"
268	depends on USB_CONFIGFS
269	depends on NET
270	select USB_U_ETHER
271	select USB_F_ECM
272	help
273	  The "Communication Device Class" (CDC) Ethernet Control Model.
274	  That protocol is often avoided with pure Ethernet adapters, in
275	  favor of simpler vendor-specific hardware, but is widely
276	  supported by firmware for smart network devices.
277
278config USB_CONFIGFS_ECM_SUBSET
279	bool "Ethernet Control Model (CDC ECM) subset"
280	depends on USB_CONFIGFS
281	depends on NET
282	select USB_U_ETHER
283	select USB_F_SUBSET
284	help
285	  On hardware that can't implement the full protocol,
286	  a simple CDC subset is used, placing fewer demands on USB.
287
288config USB_CONFIGFS_RNDIS
289	bool "RNDIS"
290	depends on USB_CONFIGFS
291	depends on NET
292	select USB_U_ETHER
293	select USB_F_RNDIS
294	help
295	   Microsoft Windows XP bundles the "Remote NDIS" (RNDIS) protocol,
296	   and Microsoft provides redistributable binary RNDIS drivers for
297	   older versions of Windows.
298
299	   To make MS-Windows work with this, use Documentation/usb/linux.inf
300	   as the "driver info file".  For versions of MS-Windows older than
301	   XP, you'll need to download drivers from Microsoft's website; a URL
302	   is given in comments found in that info file.
303
304config USB_CONFIGFS_EEM
305	bool "Ethernet Emulation Model (EEM)"
306	depends on USB_CONFIGFS
307	depends on NET
308	select USB_U_ETHER
309	select USB_F_EEM
310	help
311	  CDC EEM is a newer USB standard that is somewhat simpler than CDC ECM
312	  and therefore can be supported by more hardware.  Technically ECM and
313	  EEM are designed for different applications.  The ECM model extends
314	  the network interface to the target (e.g. a USB cable modem), and the
315	  EEM model is for mobile devices to communicate with hosts using
316	  ethernet over USB.  For Linux gadgets, however, the interface with
317	  the host is the same (a usbX device), so the differences are minimal.
318
319config USB_CONFIGFS_PHONET
320	bool "Phonet protocol"
321	depends on USB_CONFIGFS
322	depends on NET
323	depends on PHONET
324	select USB_U_ETHER
325	select USB_F_PHONET
326	help
327	  The Phonet protocol implementation for USB device.
328
329config USB_CONFIGFS_MASS_STORAGE
330	bool "Mass storage"
331	depends on USB_CONFIGFS
332	depends on BLOCK
333	select USB_F_MASS_STORAGE
334	help
335	  The Mass Storage Gadget acts as a USB Mass Storage disk drive.
336	  As its storage repository it can use a regular file or a block
337	  device (in much the same way as the "loop" device driver),
338	  specified as a module parameter or sysfs option.
339
340config USB_CONFIGFS_F_LB_SS
341	bool "Loopback and sourcesink function (for testing)"
342	depends on USB_CONFIGFS
343	select USB_F_SS_LB
344	help
345	  Loopback function loops back a configurable number of transfers.
346	  Sourcesink function either sinks and sources bulk data.
347	  It also implements control requests, for "chapter 9" conformance.
348	  Make this be the first driver you try using on top of any new
349	  USB peripheral controller driver.  Then you can use host-side
350	  test software, like the "usbtest" driver, to put your hardware
351	  and its driver through a basic set of functional tests.
352
353config USB_CONFIGFS_F_FS
354	bool "Function filesystem (FunctionFS)"
355	depends on USB_CONFIGFS
356	select USB_F_FS
357	help
358	  The Function Filesystem (FunctionFS) lets one create USB
359	  composite functions in user space in the same way GadgetFS
360	  lets one create USB gadgets in user space.  This allows creation
361	  of composite gadgets such that some of the functions are
362	  implemented in kernel space (for instance Ethernet, serial or
363	  mass storage) and other are implemented in user space.
364
365config USB_CONFIGFS_F_UAC1
366	bool "Audio Class 1.0"
367	depends on USB_CONFIGFS
368	depends on SND
369	select USB_LIBCOMPOSITE
370	select SND_PCM
371	select USB_F_UAC1
372	help
373	  This Audio function implements 1 AudioControl interface,
374	  1 AudioStreaming Interface each for USB-OUT and USB-IN.
375	  This driver requires a real Audio codec to be present
376	  on the device.
377
378config USB_CONFIGFS_F_UAC2
379	bool "Audio Class 2.0"
380	depends on USB_CONFIGFS
381	depends on SND
382	select USB_LIBCOMPOSITE
383	select SND_PCM
384	select USB_F_UAC2
385	help
386	  This Audio function is compatible with USB Audio Class
387	  specification 2.0. It 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_MIDI
397	bool "MIDI function"
398	depends on USB_CONFIGFS
399	depends on SND
400	select USB_LIBCOMPOSITE
401	select SND_RAWMIDI
402	select USB_F_MIDI
403	help
404	  The MIDI Function acts as a USB Audio device, with one MIDI
405	  input and one MIDI output. These MIDI jacks appear as
406	  a sound "card" in the ALSA sound system. Other MIDI
407	  connections can then be made on the gadget system, using
408	  ALSA's aconnect utility etc.
409
410config USB_CONFIGFS_F_HID
411	bool "HID function"
412	depends on USB_CONFIGFS
413	select USB_F_HID
414	help
415	  The HID function driver provides generic emulation of USB
416	  Human Interface Devices (HID).
417
418	  For more information, see Documentation/usb/gadget_hid.txt.
419
420config USB_CONFIGFS_F_UVC
421	bool "USB Webcam function"
422	depends on USB_CONFIGFS
423	depends on VIDEO_V4L2
424	depends on VIDEO_DEV
425	select VIDEOBUF2_VMALLOC
426	select USB_F_UVC
427	help
428	  The Webcam function acts as a composite USB Audio and Video Class
429	  device. It provides a userspace API to process UVC control requests
430	  and stream video data to the host.
431
432config USB_CONFIGFS_F_PRINTER
433	bool "Printer function"
434	select USB_F_PRINTER
435	depends on USB_CONFIGFS
436	help
437	  The Printer function channels data between the USB host and a
438	  userspace program driving the print engine. The user space
439	  program reads and writes the device file /dev/g_printer<X> to
440	  receive or send printer data. It can use ioctl calls to
441	  the device file to get or set printer status.
442
443	  For more information, see Documentation/usb/gadget_printer.txt
444	  which includes sample code for accessing the device file.
445
446config USB_CONFIGFS_F_TCM
447	bool "USB Gadget Target Fabric"
448	depends on TARGET_CORE
449	depends on USB_CONFIGFS
450	select USB_LIBCOMPOSITE
451	select USB_F_TCM
452	help
453	  This fabric is a USB gadget component. Two USB protocols are
454	  supported that is BBB or BOT (Bulk Only Transport) and UAS
455	  (USB Attached SCSI). BOT is advertised on alternative
456	  interface 0 (primary) and UAS is on alternative interface 1.
457	  Both protocols can work on USB2.0 and USB3.0.
458	  UAS utilizes the USB 3.0 feature called streams support.
459
460choice
461	tristate "USB Gadget Drivers"
462	default USB_ETH
463	help
464	  A Linux "Gadget Driver" talks to the USB Peripheral Controller
465	  driver through the abstract "gadget" API.  Some other operating
466	  systems call these "client" drivers, of which "class drivers"
467	  are a subset (implementing a USB device class specification).
468	  A gadget driver implements one or more USB functions using
469	  the peripheral hardware.
470
471	  Gadget drivers are hardware-neutral, or "platform independent",
472	  except that they sometimes must understand quirks or limitations
473	  of the particular controllers they work with.  For example, when
474	  a controller doesn't support alternate configurations or provide
475	  enough of the right types of endpoints, the gadget driver might
476	  not be able work with that controller, or might need to implement
477	  a less common variant of a device class protocol.
478
479source "drivers/usb/gadget/legacy/Kconfig"
480
481endchoice
482
483endif # USB_GADGET
484