xref: /openbmc/linux/drivers/usb/gadget/Kconfig (revision c819e2cf)
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 NLS
19	help
20	   USB is a master/slave protocol, organized with one master
21	   host (such as a PC) controlling up to 127 peripheral devices.
22	   The USB hardware is asymmetric, which makes it easier to set up:
23	   you can't connect a "to-the-host" connector to a peripheral.
24
25	   Linux can run in the host, or in the peripheral.  In both cases
26	   you need a low level bus controller driver, and some software
27	   talking to it.  Peripheral controllers are often discrete silicon,
28	   or are integrated with the CPU in a microcontroller.  The more
29	   familiar host side controllers have names like "EHCI", "OHCI",
30	   or "UHCI", and are usually integrated into southbridges on PC
31	   motherboards.
32
33	   Enable this configuration option if you want to run Linux inside
34	   a USB peripheral device.  Configure one hardware driver for your
35	   peripheral/device side bus controller, and a "gadget driver" for
36	   your peripheral protocol.  (If you use modular gadget drivers,
37	   you may configure more than one.)
38
39	   If in doubt, say "N" and don't enable these drivers; most people
40	   don't have this kind of hardware (except maybe inside Linux PDAs).
41
42	   For more information, see <http://www.linux-usb.org/gadget> and
43	   the kernel DocBook documentation for this API.
44
45if USB_GADGET
46
47config USB_GADGET_DEBUG
48	boolean "Debugging messages (DEVELOPMENT)"
49	depends on DEBUG_KERNEL
50	help
51	   Many controller and gadget drivers will print some debugging
52	   messages if you use this option to ask for those messages.
53
54	   Avoid enabling these messages, even if you're actively
55	   debugging such a driver.  Many drivers will emit so many
56	   messages that the driver timings are affected, which will
57	   either create new failure modes or remove the one you're
58	   trying to track down.  Never enable these messages for a
59	   production build.
60
61config USB_GADGET_VERBOSE
62	bool "Verbose debugging Messages (DEVELOPMENT)"
63	depends on USB_GADGET_DEBUG
64	help
65	   Many controller and gadget drivers will print verbose debugging
66	   messages if you use this option to ask for those messages.
67
68	   Avoid enabling these messages, even if you're actively
69	   debugging such a driver.  Many drivers will emit so many
70	   messages that the driver timings are affected, which will
71	   either create new failure modes or remove the one you're
72	   trying to track down.  Never enable these messages for a
73	   production build.
74
75config USB_GADGET_DEBUG_FILES
76	boolean "Debugging information files (DEVELOPMENT)"
77	depends on PROC_FS
78	help
79	   Some of the drivers in the "gadget" framework can expose
80	   debugging information in files such as /proc/driver/udc
81	   (for a peripheral controller).  The information in these
82	   files may help when you're troubleshooting or bringing up a
83	   driver on a new board.   Enable these files by choosing "Y"
84	   here.  If in doubt, or to conserve kernel memory, say "N".
85
86config USB_GADGET_DEBUG_FS
87	boolean "Debugging information files in debugfs (DEVELOPMENT)"
88	depends on DEBUG_FS
89	help
90	   Some of the drivers in the "gadget" framework can expose
91	   debugging information in files under /sys/kernel/debug/.
92	   The information in these files may help when you're
93	   troubleshooting or bringing up a driver on a new board.
94	   Enable these files by choosing "Y" here.  If in doubt, or
95	   to conserve kernel memory, say "N".
96
97config USB_GADGET_VBUS_DRAW
98	int "Maximum VBUS Power usage (2-500 mA)"
99	range 2 500
100	default 2
101	help
102	   Some devices need to draw power from USB when they are
103	   configured, perhaps to operate circuitry or to recharge
104	   batteries.  This is in addition to any local power supply,
105	   such as an AC adapter or batteries.
106
107	   Enter the maximum power your device draws through USB, in
108	   milliAmperes.  The permitted range of values is 2 - 500 mA;
109	   0 mA would be legal, but can make some hosts misbehave.
110
111	   This value will be used except for system-specific gadget
112	   drivers that have more specific information.
113
114config USB_GADGET_STORAGE_NUM_BUFFERS
115	int "Number of storage pipeline buffers"
116	range 2 4
117	default 2
118	help
119	   Usually 2 buffers are enough to establish a good buffering
120	   pipeline. The number may be increased in order to compensate
121	   for a bursty VFS behaviour. For instance there may be CPU wake up
122	   latencies that makes the VFS to appear bursty in a system with
123	   an CPU on-demand governor. Especially if DMA is doing IO to
124	   offload the CPU. In this case the CPU will go into power
125	   save often and spin up occasionally to move data within VFS.
126	   If selecting USB_GADGET_DEBUG_FILES this value may be set by
127	   a module parameter as well.
128	   If unsure, say 2.
129
130source "drivers/usb/gadget/udc/Kconfig"
131
132#
133# USB Gadget Drivers
134#
135
136# composite based drivers
137config USB_LIBCOMPOSITE
138	tristate
139	select CONFIGFS_FS
140	depends on USB_GADGET
141
142config USB_F_ACM
143	tristate
144
145config USB_F_SS_LB
146	tristate
147
148config USB_U_SERIAL
149	tristate
150
151config USB_U_ETHER
152	tristate
153
154config USB_F_SERIAL
155	tristate
156
157config USB_F_OBEX
158	tristate
159
160config USB_F_NCM
161	tristate
162
163config USB_F_ECM
164	tristate
165
166config USB_F_PHONET
167	tristate
168
169config USB_F_EEM
170	tristate
171
172config USB_F_SUBSET
173	tristate
174
175config USB_F_RNDIS
176	tristate
177
178config USB_F_MASS_STORAGE
179	tristate
180
181config USB_F_FS
182	tristate
183
184config USB_F_UAC1
185	tristate
186
187config USB_F_UAC2
188	tristate
189
190config USB_F_UVC
191	tristate
192
193config USB_F_MIDI
194	tristate
195
196config USB_F_HID
197	tristate
198
199choice
200	tristate "USB Gadget Drivers"
201	default USB_ETH
202	help
203	  A Linux "Gadget Driver" talks to the USB Peripheral Controller
204	  driver through the abstract "gadget" API.  Some other operating
205	  systems call these "client" drivers, of which "class drivers"
206	  are a subset (implementing a USB device class specification).
207	  A gadget driver implements one or more USB functions using
208	  the peripheral hardware.
209
210	  Gadget drivers are hardware-neutral, or "platform independent",
211	  except that they sometimes must understand quirks or limitations
212	  of the particular controllers they work with.  For example, when
213	  a controller doesn't support alternate configurations or provide
214	  enough of the right types of endpoints, the gadget driver might
215	  not be able work with that controller, or might need to implement
216	  a less common variant of a device class protocol.
217
218# this first set of drivers all depend on bulk-capable hardware.
219
220config USB_CONFIGFS
221	tristate "USB 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	boolean "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	boolean "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	boolean "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	boolean "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	boolean "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	boolean "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	boolean "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	boolean "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	boolean "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	boolean "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	boolean "Audio Class 1.0"
373	depends on USB_CONFIGFS
374	depends on SND
375	select USB_LIBCOMPOSITE
376	select SND_PCM
377	select USB_F_UAC1
378	help
379	  This Audio function implements 1 AudioControl interface,
380	  1 AudioStreaming Interface each for USB-OUT and USB-IN.
381	  This driver requires a real Audio codec to be present
382	  on the device.
383
384config USB_CONFIGFS_F_UAC2
385	boolean "Audio Class 2.0"
386	depends on USB_CONFIGFS
387	depends on SND
388	select USB_LIBCOMPOSITE
389	select SND_PCM
390	select USB_F_UAC2
391	help
392	  This Audio function is compatible with USB Audio Class
393	  specification 2.0. It implements 1 AudioControl interface,
394	  1 AudioStreaming Interface each for USB-OUT and USB-IN.
395	  This driver doesn't expect any real Audio codec to be present
396	  on the device - the audio streams are simply sinked to and
397	  sourced from a virtual ALSA sound card created. The user-space
398	  application may choose to do whatever it wants with the data
399	  received from the USB Host and choose to provide whatever it
400	  wants as audio data to the USB Host.
401
402config USB_CONFIGFS_F_MIDI
403	boolean "MIDI function"
404	depends on USB_CONFIGFS
405	depends on SND
406	select USB_LIBCOMPOSITE
407	select SND_RAWMIDI
408	select USB_F_MIDI
409	help
410	  The MIDI Function acts as a USB Audio device, with one MIDI
411	  input and one MIDI output. These MIDI jacks appear as
412	  a sound "card" in the ALSA sound system. Other MIDI
413	  connections can then be made on the gadget system, using
414	  ALSA's aconnect utility etc.
415
416config USB_CONFIGFS_F_HID
417	boolean "HID function"
418	depends on USB_CONFIGFS
419	select USB_F_HID
420	help
421	  The HID function driver provides generic emulation of USB
422	  Human Interface Devices (HID).
423
424	  For more information, see Documentation/usb/gadget_hid.txt.
425
426source "drivers/usb/gadget/legacy/Kconfig"
427
428endchoice
429
430endif # USB_GADGET
431