Commit | Line | Data |
---|---|---|
e38eb2c8 AP |
1 | This file summarizes information on basic testing of USB functions |
2 | provided by gadgets. | |
3 | ||
4 | 1. ACM function | |
d5862ca6 | 5 | 2. ECM function |
7bfbc6e3 | 6 | 3. ECM subset function |
4ca560a6 | 7 | 4. EEM function |
2c0f62f9 | 8 | 5. FFS function |
f7e3c3cd | 9 | 6. HID function |
ec91aff7 | 10 | 7. LOOPBACK function |
cdbe287d | 11 | 8. MASS STORAGE function |
0d6be59a | 12 | 9. MIDI function |
4d0fa79e | 13 | 10. NCM function |
d81b85dc | 14 | 11. OBEX function |
da2907d2 | 15 | 12. PHONET function |
ddb72244 | 16 | 13. RNDIS function |
4dfcec8a | 17 | 14. SERIAL function |
480a912b | 18 | 15. SOURCESINK function |
dae03586 | 19 | 16. UAC1 function |
020c6f93 | 20 | 17. UAC2 function |
9c4f538b | 21 | 18. UVC function |
ee1cd515 | 22 | 19. PRINTER function |
e38eb2c8 AP |
23 | |
24 | ||
25 | 1. ACM function | |
26 | =============== | |
27 | ||
28 | The function is provided by usb_f_acm.ko module. | |
29 | ||
30 | Function-specific configfs interface | |
31 | ------------------------------------ | |
32 | ||
33 | The function name to use when creating the function directory is "acm". | |
34 | The ACM function provides just one attribute in its function directory: | |
35 | ||
36 | port_num | |
37 | ||
38 | The attribute is read-only. | |
39 | ||
40 | There can be at most 4 ACM/generic serial/OBEX ports in the system. | |
41 | ||
42 | ||
43 | Testing the ACM function | |
44 | ------------------------ | |
45 | ||
46 | On the host: cat > /dev/ttyACM<X> | |
47 | On the device : cat /dev/ttyGS<Y> | |
48 | ||
49 | then the other way round | |
50 | ||
51 | On the device: cat > /dev/ttyGS<Y> | |
52 | On the host: cat /dev/ttyACM<X> | |
d5862ca6 AP |
53 | |
54 | 2. ECM function | |
55 | =============== | |
56 | ||
57 | The function is provided by usb_f_ecm.ko module. | |
58 | ||
59 | Function-specific configfs interface | |
60 | ------------------------------------ | |
61 | ||
62 | The function name to use when creating the function directory is "ecm". | |
63 | The ECM function provides these attributes in its function directory: | |
64 | ||
65 | ifname - network device interface name associated with this | |
66 | function instance | |
67 | qmult - queue length multiplier for high and super speed | |
68 | host_addr - MAC address of host's end of this | |
69 | Ethernet over USB link | |
70 | dev_addr - MAC address of device's end of this | |
71 | Ethernet over USB link | |
72 | ||
73 | and after creating the functions/ecm.<instance name> they contain default | |
74 | values: qmult is 5, dev_addr and host_addr are randomly selected. | |
75 | Except for ifname they can be written to until the function is linked to a | |
76 | configuration. The ifname is read-only and contains the name of the interface | |
77 | which was assigned by the net core, e. g. usb0. | |
78 | ||
79 | Testing the ECM function | |
80 | ------------------------ | |
81 | ||
82 | Configure IP addresses of the device and the host. Then: | |
83 | ||
84 | On the device: ping <host's IP> | |
85 | On the host: ping <device's IP> | |
7bfbc6e3 AP |
86 | |
87 | 3. ECM subset function | |
88 | ====================== | |
89 | ||
90 | The function is provided by usb_f_ecm_subset.ko module. | |
91 | ||
92 | Function-specific configfs interface | |
93 | ------------------------------------ | |
94 | ||
95 | The function name to use when creating the function directory is "geth". | |
96 | The ECM subset function provides these attributes in its function directory: | |
97 | ||
98 | ifname - network device interface name associated with this | |
99 | function instance | |
100 | qmult - queue length multiplier for high and super speed | |
101 | host_addr - MAC address of host's end of this | |
102 | Ethernet over USB link | |
103 | dev_addr - MAC address of device's end of this | |
104 | Ethernet over USB link | |
105 | ||
106 | and after creating the functions/ecm.<instance name> they contain default | |
107 | values: qmult is 5, dev_addr and host_addr are randomly selected. | |
108 | Except for ifname they can be written to until the function is linked to a | |
109 | configuration. The ifname is read-only and contains the name of the interface | |
110 | which was assigned by the net core, e. g. usb0. | |
111 | ||
112 | Testing the ECM subset function | |
113 | ------------------------------- | |
114 | ||
115 | Configure IP addresses of the device and the host. Then: | |
116 | ||
117 | On the device: ping <host's IP> | |
118 | On the host: ping <device's IP> | |
4ca560a6 AP |
119 | |
120 | 4. EEM function | |
121 | =============== | |
122 | ||
123 | The function is provided by usb_f_eem.ko module. | |
124 | ||
125 | Function-specific configfs interface | |
126 | ------------------------------------ | |
127 | ||
128 | The function name to use when creating the function directory is "eem". | |
129 | The EEM function provides these attributes in its function directory: | |
130 | ||
131 | ifname - network device interface name associated with this | |
132 | function instance | |
133 | qmult - queue length multiplier for high and super speed | |
134 | host_addr - MAC address of host's end of this | |
135 | Ethernet over USB link | |
136 | dev_addr - MAC address of device's end of this | |
137 | Ethernet over USB link | |
138 | ||
139 | and after creating the functions/eem.<instance name> they contain default | |
140 | values: qmult is 5, dev_addr and host_addr are randomly selected. | |
141 | Except for ifname they can be written to until the function is linked to a | |
142 | configuration. The ifname is read-only and contains the name of the interface | |
143 | which was assigned by the net core, e. g. usb0. | |
144 | ||
145 | Testing the EEM function | |
146 | ------------------------ | |
147 | ||
148 | Configure IP addresses of the device and the host. Then: | |
149 | ||
150 | On the device: ping <host's IP> | |
151 | On the host: ping <device's IP> | |
2c0f62f9 AP |
152 | |
153 | 5. FFS function | |
154 | =============== | |
155 | ||
156 | The function is provided by usb_f_fs.ko module. | |
157 | ||
158 | Function-specific configfs interface | |
159 | ------------------------------------ | |
160 | ||
161 | The function name to use when creating the function directory is "ffs". | |
162 | The function directory is intentionally empty and not modifiable. | |
163 | ||
164 | After creating the directory there is a new instance (a "device") of FunctionFS | |
165 | available in the system. Once a "device" is available, the user should follow | |
166 | the standard procedure for using FunctionFS (mount it, run the userspace | |
167 | process which implements the function proper). The gadget should be enabled | |
168 | by writing a suitable string to usb_gadget/<gadget>/UDC. | |
169 | ||
170 | Testing the FFS function | |
171 | ------------------------ | |
172 | ||
173 | On the device: start the function's userspace daemon, enable the gadget | |
174 | On the host: use the USB function provided by the device | |
f7e3c3cd AP |
175 | |
176 | 6. HID function | |
177 | =============== | |
178 | ||
179 | The function is provided by usb_f_hid.ko module. | |
180 | ||
181 | Function-specific configfs interface | |
182 | ------------------------------------ | |
183 | ||
184 | The function name to use when creating the function directory is "hid". | |
185 | The HID function provides these attributes in its function directory: | |
186 | ||
187 | protocol - HID protocol to use | |
188 | report_desc - data to be used in HID reports, except data | |
189 | passed with /dev/hidg<X> | |
190 | report_length - HID report length | |
191 | subclass - HID subclass to use | |
192 | ||
193 | For a keyboard the protocol and the subclass are 1, the report_length is 8, | |
194 | while the report_desc is: | |
195 | ||
196 | $ hd my_report_desc | |
197 | 00000000 05 01 09 06 a1 01 05 07 19 e0 29 e7 15 00 25 01 |..........)...%.| | |
198 | 00000010 75 01 95 08 81 02 95 01 75 08 81 03 95 05 75 01 |u.......u.....u.| | |
199 | 00000020 05 08 19 01 29 05 91 02 95 01 75 03 91 03 95 06 |....).....u.....| | |
200 | 00000030 75 08 15 00 25 65 05 07 19 00 29 65 81 00 c0 |u...%e....)e...| | |
201 | 0000003f | |
202 | ||
203 | Such a sequence of bytes can be stored to the attribute with echo: | |
204 | ||
205 | $ echo -ne \\x05\\x01\\x09\\x06\\xa1..... | |
206 | ||
207 | Testing the HID function | |
208 | ------------------------ | |
209 | ||
210 | Device: | |
211 | - create the gadget | |
212 | - connect the gadget to a host, preferably not the one used | |
213 | to control the gadget | |
214 | - run a program which writes to /dev/hidg<N>, e.g. | |
215 | a userspace program found in Documentation/usb/gadget_hid.txt: | |
216 | ||
217 | $ ./hid_gadget_test /dev/hidg0 keyboard | |
218 | ||
219 | Host: | |
220 | - observe the keystrokes from the gadget | |
ec91aff7 AP |
221 | |
222 | 7. LOOPBACK function | |
223 | ==================== | |
224 | ||
225 | The function is provided by usb_f_ss_lb.ko module. | |
226 | ||
227 | Function-specific configfs interface | |
228 | ------------------------------------ | |
229 | ||
230 | The function name to use when creating the function directory is "Loopback". | |
231 | The LOOPBACK function provides these attributes in its function directory: | |
232 | ||
233 | qlen - depth of loopback queue | |
234 | bulk_buflen - buffer length | |
235 | ||
236 | Testing the LOOPBACK function | |
237 | ----------------------------- | |
238 | ||
239 | device: run the gadget | |
240 | host: test-usb | |
241 | ||
242 | http://www.linux-usb.org/usbtest/testusb.c | |
cdbe287d AP |
243 | |
244 | 8. MASS STORAGE function | |
245 | ======================== | |
246 | ||
247 | The function is provided by usb_f_mass_storage.ko module. | |
248 | ||
249 | Function-specific configfs interface | |
250 | ------------------------------------ | |
251 | ||
252 | The function name to use when creating the function directory is "mass_storage". | |
253 | The MASS STORAGE function provides these attributes in its directory: | |
254 | files: | |
255 | ||
256 | stall - Set to permit function to halt bulk endpoints. | |
257 | Disabled on some USB devices known not to work | |
258 | correctly. You should set it to true. | |
259 | num_buffers - Number of pipeline buffers. Valid numbers | |
260 | are 2..4. Available only if | |
261 | CONFIG_USB_GADGET_DEBUG_FILES is set. | |
262 | ||
263 | and a default lun.0 directory corresponding to SCSI LUN #0. | |
264 | ||
265 | A new lun can be added with mkdir: | |
266 | ||
267 | $ mkdir functions/mass_storage.0/partition.5 | |
268 | ||
269 | Lun numbering does not have to be continuous, except for lun #0 which is | |
270 | created by default. A maximum of 8 luns can be specified and they all must be | |
271 | named following the <name>.<number> scheme. The numbers can be 0..8. | |
272 | Probably a good convention is to name the luns "lun.<number>", | |
273 | although it is not mandatory. | |
274 | ||
275 | In each lun directory there are the following attribute files: | |
276 | ||
277 | file - The path to the backing file for the LUN. | |
278 | Required if LUN is not marked as removable. | |
279 | ro - Flag specifying access to the LUN shall be | |
280 | read-only. This is implied if CD-ROM emulation | |
281 | is enabled as well as when it was impossible | |
282 | to open "filename" in R/W mode. | |
283 | removable - Flag specifying that LUN shall be indicated as | |
284 | being removable. | |
285 | cdrom - Flag specifying that LUN shall be reported as | |
286 | being a CD-ROM. | |
287 | nofua - Flag specifying that FUA flag | |
288 | in SCSI WRITE(10,12) | |
289 | ||
290 | Testing the MASS STORAGE function | |
291 | --------------------------------- | |
292 | ||
293 | device: connect the gadget, enable it | |
294 | host: dmesg, see the USB drives appear (if system configured to automatically | |
295 | mount) | |
0d6be59a AP |
296 | |
297 | 9. MIDI function | |
298 | ================ | |
299 | ||
300 | The function is provided by usb_f_midi.ko module. | |
301 | ||
302 | Function-specific configfs interface | |
303 | ------------------------------------ | |
304 | ||
305 | The function name to use when creating the function directory is "midi". | |
306 | The MIDI function provides these attributes in its function directory: | |
307 | ||
308 | buflen - MIDI buffer length | |
309 | id - ID string for the USB MIDI adapter | |
310 | in_ports - number of MIDI input ports | |
311 | index - index value for the USB MIDI adapter | |
312 | out_ports - number of MIDI output ports | |
313 | qlen - USB read request queue length | |
314 | ||
315 | Testing the MIDI function | |
316 | ------------------------- | |
317 | ||
318 | There are two cases: playing a mid from the gadget to | |
319 | the host and playing a mid from the host to the gadget. | |
320 | ||
321 | 1) Playing a mid from the gadget to the host | |
322 | host) | |
323 | ||
324 | $ arecordmidi -l | |
325 | Port Client name Port name | |
326 | 14:0 Midi Through Midi Through Port-0 | |
327 | 24:0 MIDI Gadget MIDI Gadget MIDI 1 | |
328 | $ arecordmidi -p 24:0 from_gadget.mid | |
329 | ||
330 | gadget) | |
331 | ||
332 | $ aplaymidi -l | |
333 | Port Client name Port name | |
334 | 20:0 f_midi f_midi | |
335 | ||
336 | $ aplaymidi -p 20:0 to_host.mid | |
337 | ||
338 | 2) Playing a mid from the host to the gadget | |
339 | gadget) | |
340 | ||
341 | $ arecordmidi -l | |
342 | Port Client name Port name | |
343 | 20:0 f_midi f_midi | |
344 | ||
345 | $ arecordmidi -p 20:0 from_host.mid | |
346 | ||
347 | host) | |
348 | ||
349 | $ aplaymidi -l | |
350 | Port Client name Port name | |
351 | 14:0 Midi Through Midi Through Port-0 | |
352 | 24:0 MIDI Gadget MIDI Gadget MIDI 1 | |
353 | ||
354 | $ aplaymidi -p24:0 to_gadget.mid | |
355 | ||
356 | The from_gadget.mid should sound identical to the to_host.mid. | |
357 | The from_host.id should sound identical to the to_gadget.mid. | |
358 | ||
359 | MIDI files can be played to speakers/headphones with e.g. timidity installed | |
360 | ||
361 | $ aplaymidi -l | |
362 | Port Client name Port name | |
363 | 14:0 Midi Through Midi Through Port-0 | |
364 | 24:0 MIDI Gadget MIDI Gadget MIDI 1 | |
365 | 128:0 TiMidity TiMidity port 0 | |
366 | 128:1 TiMidity TiMidity port 1 | |
367 | 128:2 TiMidity TiMidity port 2 | |
368 | 128:3 TiMidity TiMidity port 3 | |
369 | ||
370 | $ aplaymidi -p 128:0 file.mid | |
371 | ||
372 | MIDI ports can be logically connected using the aconnect utility, e.g.: | |
373 | ||
374 | $ aconnect 24:0 128:0 # try it on the host | |
375 | ||
376 | After the gadget's MIDI port is connected to timidity's MIDI port, | |
377 | whatever is played at the gadget side with aplaymidi -l is audible | |
378 | in host's speakers/headphones. | |
4d0fa79e AP |
379 | |
380 | 10. NCM function | |
381 | ================ | |
382 | ||
383 | The function is provided by usb_f_ncm.ko module. | |
384 | ||
385 | Function-specific configfs interface | |
386 | ------------------------------------ | |
387 | ||
388 | The function name to use when creating the function directory is "ncm". | |
389 | The NCM function provides these attributes in its function directory: | |
390 | ||
391 | ifname - network device interface name associated with this | |
392 | function instance | |
393 | qmult - queue length multiplier for high and super speed | |
394 | host_addr - MAC address of host's end of this | |
395 | Ethernet over USB link | |
396 | dev_addr - MAC address of device's end of this | |
397 | Ethernet over USB link | |
398 | ||
399 | and after creating the functions/ncm.<instance name> they contain default | |
400 | values: qmult is 5, dev_addr and host_addr are randomly selected. | |
401 | Except for ifname they can be written to until the function is linked to a | |
402 | configuration. The ifname is read-only and contains the name of the interface | |
403 | which was assigned by the net core, e. g. usb0. | |
404 | ||
405 | Testing the NCM function | |
406 | ------------------------ | |
407 | ||
408 | Configure IP addresses of the device and the host. Then: | |
409 | ||
410 | On the device: ping <host's IP> | |
411 | On the host: ping <device's IP> | |
d81b85dc AP |
412 | |
413 | 11. OBEX function | |
414 | ================= | |
415 | ||
416 | The function is provided by usb_f_obex.ko module. | |
417 | ||
418 | Function-specific configfs interface | |
419 | ------------------------------------ | |
420 | ||
421 | The function name to use when creating the function directory is "obex". | |
422 | The OBEX function provides just one attribute in its function directory: | |
423 | ||
424 | port_num | |
425 | ||
426 | The attribute is read-only. | |
427 | ||
428 | There can be at most 4 ACM/generic serial/OBEX ports in the system. | |
429 | ||
430 | Testing the OBEX function | |
431 | ------------------------- | |
432 | ||
433 | On device: seriald -f /dev/ttyGS<Y> -s 1024 | |
434 | On host: serialc -v <vendorID> -p <productID> -i<interface#> -a1 -s1024 \ | |
435 | -t<out endpoint addr> -r<in endpoint addr> | |
436 | ||
437 | where seriald and serialc are Felipe's utilities found here: | |
438 | ||
439 | https://git.gitorious.org/usb/usb-tools.git master | |
da2907d2 AP |
440 | |
441 | 12. PHONET function | |
442 | =================== | |
443 | ||
444 | The function is provided by usb_f_phonet.ko module. | |
445 | ||
446 | Function-specific configfs interface | |
447 | ------------------------------------ | |
448 | ||
449 | The function name to use when creating the function directory is "phonet". | |
450 | The PHONET function provides just one attribute in its function directory: | |
451 | ||
452 | ifname - network device interface name associated with this | |
453 | function instance | |
454 | ||
455 | Testing the PHONET function | |
456 | --------------------------- | |
457 | ||
458 | It is not possible to test the SOCK_STREAM protocol without a specific piece | |
459 | of hardware, so only SOCK_DGRAM has been tested. For the latter to work, | |
460 | in the past I had to apply the patch mentioned here: | |
461 | ||
462 | http://www.spinics.net/lists/linux-usb/msg85689.html | |
463 | ||
464 | These tools are required: | |
465 | ||
466 | git://git.gitorious.org/meego-cellular/phonet-utils.git | |
467 | ||
468 | On the host: | |
469 | ||
470 | $ ./phonet -a 0x10 -i usbpn0 | |
471 | $ ./pnroute add 0x6c usbpn0 | |
472 | $./pnroute add 0x10 usbpn0 | |
473 | $ ifconfig usbpn0 up | |
474 | ||
475 | On the device: | |
476 | ||
477 | $ ./phonet -a 0x6c -i upnlink0 | |
478 | $ ./pnroute add 0x10 upnlink0 | |
479 | $ ifconfig upnlink0 up | |
480 | ||
481 | Then a test program can be used: | |
482 | ||
483 | http://www.spinics.net/lists/linux-usb/msg85690.html | |
484 | ||
485 | On the device: | |
486 | ||
487 | $ ./pnxmit -a 0x6c -r | |
488 | ||
489 | On the host: | |
490 | ||
491 | $ ./pnxmit -a 0x10 -s 0x6c | |
492 | ||
493 | As a result some data should be sent from host to device. | |
494 | Then the other way round: | |
495 | ||
496 | On the host: | |
497 | ||
498 | $ ./pnxmit -a 0x10 -r | |
499 | ||
500 | On the device: | |
501 | ||
502 | $ ./pnxmit -a 0x6c -s 0x10 | |
ddb72244 AP |
503 | |
504 | 13. RNDIS function | |
505 | ================== | |
506 | ||
507 | The function is provided by usb_f_rndis.ko module. | |
508 | ||
509 | Function-specific configfs interface | |
510 | ------------------------------------ | |
511 | ||
512 | The function name to use when creating the function directory is "rndis". | |
513 | The RNDIS function provides these attributes in its function directory: | |
514 | ||
515 | ifname - network device interface name associated with this | |
516 | function instance | |
517 | qmult - queue length multiplier for high and super speed | |
518 | host_addr - MAC address of host's end of this | |
519 | Ethernet over USB link | |
520 | dev_addr - MAC address of device's end of this | |
521 | Ethernet over USB link | |
522 | ||
523 | and after creating the functions/rndis.<instance name> they contain default | |
524 | values: qmult is 5, dev_addr and host_addr are randomly selected. | |
525 | Except for ifname they can be written to until the function is linked to a | |
526 | configuration. The ifname is read-only and contains the name of the interface | |
527 | which was assigned by the net core, e. g. usb0. | |
528 | ||
529 | By default there can be only 1 RNDIS interface in the system. | |
530 | ||
531 | Testing the RNDIS function | |
532 | -------------------------- | |
533 | ||
534 | Configure IP addresses of the device and the host. Then: | |
535 | ||
536 | On the device: ping <host's IP> | |
537 | On the host: ping <device's IP> | |
4dfcec8a AP |
538 | |
539 | 14. SERIAL function | |
540 | =================== | |
541 | ||
542 | The function is provided by usb_f_gser.ko module. | |
543 | ||
544 | Function-specific configfs interface | |
545 | ------------------------------------ | |
546 | ||
547 | The function name to use when creating the function directory is "gser". | |
548 | The SERIAL function provides just one attribute in its function directory: | |
549 | ||
550 | port_num | |
551 | ||
552 | The attribute is read-only. | |
553 | ||
554 | There can be at most 4 ACM/generic serial/OBEX ports in the system. | |
555 | ||
556 | Testing the SERIAL function | |
557 | --------------------------- | |
558 | ||
559 | On host: insmod usbserial | |
560 | echo VID PID >/sys/bus/usb-serial/drivers/generic/new_id | |
561 | On host: cat > /dev/ttyUSB<X> | |
562 | On target: cat /dev/ttyGS<Y> | |
563 | ||
564 | then the other way round | |
565 | ||
566 | On target: cat > /dev/ttyGS<Y> | |
567 | On host: cat /dev/ttyUSB<X> | |
480a912b AP |
568 | |
569 | 15. SOURCESINK function | |
570 | ======================= | |
571 | ||
572 | The function is provided by usb_f_ss_lb.ko module. | |
573 | ||
574 | Function-specific configfs interface | |
575 | ------------------------------------ | |
576 | ||
577 | The function name to use when creating the function directory is "SourceSink". | |
578 | The SOURCESINK function provides these attributes in its function directory: | |
579 | ||
580 | pattern - 0 (all zeros), 1 (mod63), 2 (none) | |
581 | isoc_interval - 1..16 | |
582 | isoc_maxpacket - 0 - 1023 (fs), 0 - 1024 (hs/ss) | |
583 | isoc_mult - 0..2 (hs/ss only) | |
584 | isoc_maxburst - 0..15 (ss only) | |
585 | bulk_buflen - buffer length | |
586 | ||
587 | Testing the SOURCESINK function | |
588 | ------------------------------- | |
589 | ||
590 | device: run the gadget | |
591 | host: test-usb | |
592 | ||
593 | http://www.linux-usb.org/usbtest/testusb.c | |
dae03586 AP |
594 | |
595 | 16. UAC1 function | |
596 | ================= | |
597 | ||
598 | The function is provided by usb_f_uac1.ko module. | |
599 | ||
600 | Function-specific configfs interface | |
601 | ------------------------------------ | |
602 | ||
603 | The function name to use when creating the function directory is "uac1". | |
604 | The uac1 function provides these attributes in its function directory: | |
605 | ||
606 | audio_buf_size - audio buffer size | |
607 | fn_cap - capture pcm device file name | |
608 | fn_cntl - control device file name | |
609 | fn_play - playback pcm device file name | |
610 | req_buf_size - ISO OUT endpoint request buffer size | |
611 | req_count - ISO OUT endpoint request count | |
612 | ||
613 | The attributes have sane default values. | |
614 | ||
615 | Testing the UAC1 function | |
616 | ------------------------- | |
617 | ||
618 | device: run the gadget | |
619 | host: aplay -l # should list our USB Audio Gadget | |
020c6f93 AP |
620 | |
621 | 17. UAC2 function | |
622 | ================= | |
623 | ||
624 | The function is provided by usb_f_uac2.ko module. | |
625 | ||
626 | Function-specific configfs interface | |
627 | ------------------------------------ | |
628 | ||
629 | The function name to use when creating the function directory is "uac2". | |
630 | The uac2 function provides these attributes in its function directory: | |
631 | ||
632 | chmask - capture channel mask | |
633 | c_srate - capture sampling rate | |
634 | c_ssize - capture sample size (bytes) | |
635 | p_chmask - playback channel mask | |
636 | p_srate - playback sampling rate | |
637 | p_ssize - playback sample size (bytes) | |
638 | ||
639 | The attributes have sane default values. | |
640 | ||
641 | Testing the UAC2 function | |
642 | ------------------------- | |
643 | ||
644 | device: run the gadget | |
645 | host: aplay -l # should list our USB Audio Gadget | |
646 | ||
647 | This function does not require real hardware support, it just | |
648 | sends a stream of audio data to/from the host. In order to | |
649 | actually hear something at the device side, a command similar | |
650 | to this must be used at the device side: | |
651 | ||
652 | $ arecord -f dat -t wav -D hw:2,0 | aplay -D hw:0,0 & | |
653 | ||
654 | e.g.: | |
655 | ||
656 | $ arecord -f dat -t wav -D hw:CARD=UAC2Gadget,DEV=0 | \ | |
657 | aplay -D default:CARD=OdroidU3 | |
9c4f538b AP |
658 | |
659 | 18. UVC function | |
660 | ================ | |
661 | ||
662 | The function is provided by usb_f_uvc.ko module. | |
663 | ||
664 | Function-specific configfs interface | |
665 | ------------------------------------ | |
666 | ||
667 | The function name to use when creating the function directory is "uvc". | |
668 | The uvc function provides these attributes in its function directory: | |
669 | ||
670 | streaming_interval - interval for polling endpoint for data transfers | |
671 | streaming_maxburst - bMaxBurst for super speed companion descriptor | |
672 | streaming_maxpacket - maximum packet size this endpoint is capable of | |
673 | sending or receiving when this configuration is | |
674 | selected | |
675 | ||
676 | There are also "control" and "streaming" subdirectories, each of which contain | |
677 | a number of their subdirectories. There are some sane defaults provided, but | |
678 | the user must provide the following: | |
679 | ||
680 | control header - create in control/header, link from control/class/fs | |
681 | and/or control/class/ss | |
682 | streaming header - create in streaming/header, link from | |
683 | streaming/class/fs and/or streaming/class/hs and/or | |
684 | streaming/class/ss | |
685 | format description - create in streaming/mjpeg and/or | |
686 | streaming/uncompressed | |
687 | frame description - create in streaming/mjpeg/<format> and/or in | |
688 | streaming/uncompressed/<format> | |
689 | ||
690 | Each frame description contains frame interval specification, and each | |
691 | such specification consists of a number of lines with an inverval value | |
692 | in each line. The rules stated above are best illustrated with an example: | |
693 | ||
694 | # mkdir functions/uvc.usb0/control/header/h | |
695 | # cd functions/uvc.usb0/control/header/h | |
696 | # ln -s header/h class/fs | |
697 | # ln -s header/h class/ss | |
698 | # mkdir -p functions/uvc.usb0/streaming/uncompressed/u/360p | |
699 | # cat <<EOF > functions/uvc.usb0/streaming/uncompressed/u/360p/dwFrameInterval | |
700 | 666666 | |
701 | 1000000 | |
702 | 5000000 | |
703 | EOF | |
704 | # cd $GADGET_CONFIGFS_ROOT | |
705 | # mkdir functions/uvc.usb0/streaming/header/h | |
706 | # cd functions/uvc.usb0/streaming/header/h | |
707 | # ln -s ../../uncompressed/u | |
708 | # cd ../../class/fs | |
709 | # ln -s ../../header/h | |
710 | # cd ../../class/hs | |
711 | # ln -s ../../header/h | |
712 | # cd ../../class/ss | |
713 | # ln -s ../../header/h | |
714 | ||
715 | ||
716 | Testing the UVC function | |
717 | ------------------------ | |
718 | ||
719 | device: run the gadget, modprobe vivid | |
720 | ||
721 | # uvc-gadget -u /dev/video<uvc video node #> -v /dev/video<vivid video node #> | |
722 | ||
723 | where uvc-gadget is this program: | |
724 | http://git.ideasonboard.org/uvc-gadget.git | |
725 | ||
726 | with these patches: | |
727 | http://www.spinics.net/lists/linux-usb/msg99220.html | |
728 | ||
729 | host: luvcview -f yuv | |
ee1cd515 AP |
730 | |
731 | 19. PRINTER function | |
732 | ==================== | |
733 | ||
734 | The function is provided by usb_f_printer.ko module. | |
735 | ||
736 | Function-specific configfs interface | |
737 | ------------------------------------ | |
738 | ||
739 | The function name to use when creating the function directory is "printer". | |
740 | The printer function provides these attributes in its function directory: | |
741 | ||
742 | pnp_string - Data to be passed to the host in pnp string | |
743 | q_len - Number of requests per endpoint | |
744 | ||
745 | Testing the PRINTER function | |
746 | ---------------------------- | |
747 | ||
748 | The most basic testing: | |
749 | ||
750 | device: run the gadget | |
751 | # ls -l /devices/virtual/usb_printer_gadget/ | |
752 | ||
753 | should show g_printer<number>. | |
754 | ||
755 | If udev is active, then /dev/g_printer<number> should appear automatically. | |
756 | ||
757 | host: | |
758 | ||
759 | If udev is active, then e.g. /dev/usb/lp0 should appear. | |
760 | ||
761 | host->device transmission: | |
762 | ||
763 | device: | |
764 | # cat /dev/g_printer<number> | |
765 | host: | |
766 | # cat > /dev/usb/lp0 | |
767 | ||
768 | device->host transmission: | |
769 | ||
770 | # cat > /dev/g_printer<number> | |
771 | host: | |
772 | # cat /dev/usb/lp0 | |
773 | ||
774 | More advanced testing can be done with the prn_example | |
775 | described in Documentation/usb/gadget-printer.txt. |