summaryrefslogtreecommitdiffstats
path: root/Documentation/usb/gadget-testing.txt
blob: 58196057488941ebc2aa23e116dbb01d1d153c8b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
This file summarizes information on basic testing of USB functions
provided by gadgets.

1. ACM function
2. ECM function
3. ECM subset function
4. EEM function
5. FFS function
6. HID function
7. LOOPBACK function
8. MASS STORAGE function
9. MIDI function
10. NCM function
11. OBEX function
12. PHONET function
13. RNDIS function
14. SERIAL function
15. SOURCESINK function
16. UAC1 function
17. UAC2 function
18. UVC function
19. PRINTER function


1. ACM function
===============

The function is provided by usb_f_acm.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "acm".
The ACM function provides just one attribute in its function directory:

	port_num

The attribute is read-only.

There can be at most 4 ACM/generic serial/OBEX ports in the system.


Testing the ACM function
------------------------

On the host: cat > /dev/ttyACM<X>
On the device : cat /dev/ttyGS<Y>

then the other way round

On the device: cat > /dev/ttyGS<Y>
On the host: cat /dev/ttyACM<X>

2. ECM function
===============

The function is provided by usb_f_ecm.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "ecm".
The ECM function provides these attributes in its function directory:

	ifname		- network device interface name associated with this
			function instance
	qmult		- queue length multiplier for high and super speed
	host_addr	- MAC address of host's end of this
			Ethernet over USB link
	dev_addr	- MAC address of device's end of this
			Ethernet over USB link

and after creating the functions/ecm.<instance name> they contain default
values: qmult is 5, dev_addr and host_addr are randomly selected.
Except for ifname they can be written to until the function is linked to a
configuration. The ifname is read-only and contains the name of the interface
which was assigned by the net core, e. g. usb0.

Testing the ECM function
------------------------

Configure IP addresses of the device and the host. Then:

On the device: ping <host's IP>
On the host: ping <device's IP>

3. ECM subset function
======================

The function is provided by usb_f_ecm_subset.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "geth".
The ECM subset function provides these attributes in its function directory:

	ifname		- network device interface name associated with this
			function instance
	qmult		- queue length multiplier for high and super speed
	host_addr	- MAC address of host's end of this
			Ethernet over USB link
	dev_addr	- MAC address of device's end of this
			Ethernet over USB link

and after creating the functions/ecm.<instance name> they contain default
values: qmult is 5, dev_addr and host_addr are randomly selected.
Except for ifname they can be written to until the function is linked to a
configuration. The ifname is read-only and contains the name of the interface
which was assigned by the net core, e. g. usb0.

Testing the ECM subset function
-------------------------------

Configure IP addresses of the device and the host. Then:

On the device: ping <host's IP>
On the host: ping <device's IP>

4. EEM function
===============

The function is provided by usb_f_eem.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "eem".
The EEM function provides these attributes in its function directory:

	ifname		- network device interface name associated with this
			function instance
	qmult		- queue length multiplier for high and super speed
	host_addr	- MAC address of host's end of this
			Ethernet over USB link
	dev_addr	- MAC address of device's end of this
			Ethernet over USB link

and after creating the functions/eem.<instance name> they contain default
values: qmult is 5, dev_addr and host_addr are randomly selected.
Except for ifname they can be written to until the function is linked to a
configuration. The ifname is read-only and contains the name of the interface
which was assigned by the net core, e. g. usb0.

Testing the EEM function
------------------------

Configure IP addresses of the device and the host. Then:

On the device: ping <host's IP>
On the host: ping <device's IP>

5. FFS function
===============

The function is provided by usb_f_fs.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "ffs".
The function directory is intentionally empty and not modifiable.

After creating the directory there is a new instance (a "device") of FunctionFS
available in the system. Once a "device" is available, the user should follow
the standard procedure for using FunctionFS (mount it, run the userspace
process which implements the function proper). The gadget should be enabled
by writing a suitable string to usb_gadget/<gadget>/UDC.

Testing the FFS function
------------------------

On the device: start the function's userspace daemon, enable the gadget
On the host: use the USB function provided by the device

6. HID function
===============

The function is provided by usb_f_hid.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "hid".
The HID function provides these attributes in its function directory:

	protocol	- HID protocol to use
	report_desc	- data to be used in HID reports, except data
			passed with /dev/hidg<X>
	report_length	- HID report length
	subclass	- HID subclass to use

For a keyboard the protocol and the subclass are 1, the report_length is 8,
while the report_desc is:

$ hd my_report_desc
00000000  05 01 09 06 a1 01 05 07  19 e0 29 e7 15 00 25 01  |..........)...%.|
00000010  75 01 95 08 81 02 95 01  75 08 81 03 95 05 75 01  |u.......u.....u.|
00000020  05 08 19 01 29 05 91 02  95 01 75 03 91 03 95 06  |....).....u.....|
00000030  75 08 15 00 25 65 05 07  19 00 29 65 81 00 c0     |u...%e....)e...|
0000003f

Such a sequence of bytes can be stored to the attribute with echo:

$ echo -ne \\x05\\x01\\x09\\x06\\xa1.....

Testing the HID function
------------------------

Device:
- create the gadget
- connect the gadget to a host, preferably not the one used
to control the gadget
- run a program which writes to /dev/hidg<N>, e.g.
a userspace program found in Documentation/usb/gadget_hid.txt:

$ ./hid_gadget_test /dev/hidg0 keyboard

Host:
- observe the keystrokes from the gadget

7. LOOPBACK function
====================

The function is provided by usb_f_ss_lb.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "Loopback".
The LOOPBACK function provides these attributes in its function directory:

	qlen		- depth of loopback queue
	bulk_buflen	- buffer length

Testing the LOOPBACK function
-----------------------------

device: run the gadget
host: test-usb (tools/usb/testusb.c)

8. MASS STORAGE function
========================

The function is provided by usb_f_mass_storage.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "mass_storage".
The MASS STORAGE function provides these attributes in its directory:
files:

	stall		- Set to permit function to halt bulk endpoints.
			Disabled on some USB devices known not to work
			correctly. You should set it to true.
	num_buffers	- Number of pipeline buffers. Valid numbers
			are 2..4. Available only if
			CONFIG_USB_GADGET_DEBUG_FILES is set.

and a default lun.0 directory corresponding to SCSI LUN #0.

A new lun can be added with mkdir:

$ mkdir functions/mass_storage.0/partition.5

Lun numbering does not have to be continuous, except for lun #0 which is
created by default. A maximum of 8 luns can be specified and they all must be
named following the <name>.<number> scheme. The numbers can be 0..8.
Probably a good convention is to name the luns "lun.<number>",
although it is not mandatory.

In each lun directory there are the following attribute files:

	file		- The path to the backing file for the LUN.
			Required if LUN is not marked as removable.
	ro		- Flag specifying access to the LUN shall be
			read-only. This is implied if CD-ROM emulation
			is enabled as well as when it was impossible
			to open "filename" in R/W mode.
	removable	- Flag specifying that LUN shall be indicated as
			being removable.
	cdrom		- Flag specifying that LUN shall be reported as
			being a CD-ROM.
	nofua		- Flag specifying that FUA flag
			in SCSI WRITE(10,12)

Testing the MASS STORAGE function
---------------------------------

device: connect the gadget, enable it
host: dmesg, see the USB drives appear (if system configured to automatically
mount)

9. MIDI function
================

The function is provided by usb_f_midi.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "midi".
The MIDI function provides these attributes in its function directory:

	buflen		- MIDI buffer length
	id		- ID string for the USB MIDI adapter
	in_ports	- number of MIDI input ports
	index		- index value for the USB MIDI adapter
	out_ports	- number of MIDI output ports
	qlen		- USB read request queue length

Testing the MIDI function
-------------------------

There are two cases: playing a mid from the gadget to
the host and playing a mid from the host to the gadget.

1) Playing a mid from the gadget to the host
host)

$ arecordmidi -l
 Port    Client name                      Port name
 14:0    Midi Through                     Midi Through Port-0
 24:0    MIDI Gadget                      MIDI Gadget MIDI 1
$ arecordmidi -p 24:0 from_gadget.mid

gadget)

$ aplaymidi -l
 Port    Client name                      Port name
 20:0    f_midi                           f_midi

$ aplaymidi -p 20:0 to_host.mid

2) Playing a mid from the host to the gadget
gadget)

$ arecordmidi -l
 Port    Client name                      Port name
 20:0    f_midi                           f_midi

$ arecordmidi -p 20:0 from_host.mid

host)

$ aplaymidi -l
 Port    Client name                      Port name
 14:0    Midi Through                     Midi Through Port-0
 24:0    MIDI Gadget                      MIDI Gadget MIDI 1

$ aplaymidi -p24:0 to_gadget.mid

The from_gadget.mid should sound identical to the to_host.mid.
The from_host.id should sound identical to the to_gadget.mid.

MIDI files can be played to speakers/headphones with e.g. timidity installed

$ aplaymidi -l
 Port    Client name                      Port name
 14:0    Midi Through                     Midi Through Port-0
 24:0    MIDI Gadget                      MIDI Gadget MIDI 1
128:0    TiMidity                         TiMidity port 0
128:1    TiMidity                         TiMidity port 1
128:2    TiMidity                         TiMidity port 2
128:3    TiMidity                         TiMidity port 3

$ aplaymidi -p 128:0 file.mid

MIDI ports can be logically connected using the aconnect utility, e.g.:

$ aconnect 24:0 128:0 # try it on the host

After the gadget's MIDI port is connected to timidity's MIDI port,
whatever is played at the gadget side with aplaymidi -l is audible
in host's speakers/headphones.

10. NCM function
================

The function is provided by usb_f_ncm.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "ncm".
The NCM function provides these attributes in its function directory:

	ifname		- network device interface name associated with this
			function instance
	qmult		- queue length multiplier for high and super speed
	host_addr	- MAC address of host's end of this
			Ethernet over USB link
	dev_addr	- MAC address of device's end of this
			Ethernet over USB link

and after creating the functions/ncm.<instance name> they contain default
values: qmult is 5, dev_addr and host_addr are randomly selected.
Except for ifname they can be written to until the function is linked to a
configuration. The ifname is read-only and contains the name of the interface
which was assigned by the net core, e. g. usb0.

Testing the NCM function
------------------------

Configure IP addresses of the device and the host. Then:

On the device: ping <host's IP>
On the host: ping <device's IP>

11. OBEX function
=================

The function is provided by usb_f_obex.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "obex".
The OBEX function provides just one attribute in its function directory:

	port_num

The attribute is read-only.

There can be at most 4 ACM/generic serial/OBEX ports in the system.

Testing the OBEX function
-------------------------

On device: seriald -f /dev/ttyGS<Y> -s 1024
On host: serialc -v <vendorID> -p <productID> -i<interface#> -a1 -s1024 \
             -t<out endpoint addr> -r<in endpoint addr>

where seriald and serialc are Felipe's utilities found here:

https://github.com/felipebalbi/usb-tools.git master

12. PHONET function
===================

The function is provided by usb_f_phonet.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "phonet".
The PHONET function provides just one attribute in its function directory:

	ifname		- network device interface name associated with this
			function instance

Testing the PHONET function
---------------------------

It is not possible to test the SOCK_STREAM protocol without a specific piece
of hardware, so only SOCK_DGRAM has been tested. For the latter to work,
in the past I had to apply the patch mentioned here:

http://www.spinics.net/lists/linux-usb/msg85689.html

These tools are required:

git://git.gitorious.org/meego-cellular/phonet-utils.git

On the host:

$ ./phonet -a 0x10 -i usbpn0
$ ./pnroute add 0x6c usbpn0
$./pnroute add 0x10 usbpn0
$ ifconfig usbpn0 up

On the device:

$ ./phonet -a 0x6c -i upnlink0
$ ./pnroute add 0x10 upnlink0
$ ifconfig upnlink0 up

Then a test program can be used:

http://www.spinics.net/lists/linux-usb/msg85690.html

On the device:

$ ./pnxmit -a 0x6c -r

On the host:

$ ./pnxmit -a 0x10 -s 0x6c

As a result some data should be sent from host to device.
Then the other way round:

On the host:

$ ./pnxmit -a 0x10 -r

On the device:

$ ./pnxmit -a 0x6c -s 0x10

13. RNDIS function
==================

The function is provided by usb_f_rndis.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "rndis".
The RNDIS function provides these attributes in its function directory:

	ifname		- network device interface name associated with this
			function instance
	qmult		- queue length multiplier for high and super speed
	host_addr	- MAC address of host's end of this
			Ethernet over USB link
	dev_addr	- MAC address of device's end of this
			Ethernet over USB link

and after creating the functions/rndis.<instance name> they contain default
values: qmult is 5, dev_addr and host_addr are randomly selected.
Except for ifname they can be written to until the function is linked to a
configuration. The ifname is read-only and contains the name of the interface
which was assigned by the net core, e. g. usb0.

Testing the RNDIS function
--------------------------

Configure IP addresses of the device and the host. Then:

On the device: ping <host's IP>
On the host: ping <device's IP>

14. SERIAL function
===================

The function is provided by usb_f_gser.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "gser".
The SERIAL function provides just one attribute in its function directory:

	port_num

The attribute is read-only.

There can be at most 4 ACM/generic serial/OBEX ports in the system.

Testing the SERIAL function
---------------------------

On host: insmod usbserial
	 echo VID PID >/sys/bus/usb-serial/drivers/generic/new_id
On host: cat > /dev/ttyUSB<X>
On target: cat /dev/ttyGS<Y>

then the other way round

On target: cat > /dev/ttyGS<Y>
On host: cat /dev/ttyUSB<X>

15. SOURCESINK function
=======================

The function is provided by usb_f_ss_lb.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "SourceSink".
The SOURCESINK function provides these attributes in its function directory:

	pattern		- 0 (all zeros), 1 (mod63), 2 (none)
	isoc_interval	- 1..16
	isoc_maxpacket	- 0 - 1023 (fs), 0 - 1024 (hs/ss)
	isoc_mult	- 0..2 (hs/ss only)
	isoc_maxburst	- 0..15 (ss only)
	bulk_buflen	- buffer length
	bulk_qlen	- depth of queue for bulk
	iso_qlen	- depth of queue for iso

Testing the SOURCESINK function
-------------------------------

device: run the gadget
host: test-usb (tools/usb/testusb.c)


16. UAC1 function
=================

The function is provided by usb_f_uac1.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "uac1".
The uac1 function provides these attributes in its function directory:

	audio_buf_size - audio buffer size
	fn_cap - capture pcm device file name
	fn_cntl - control device file name
	fn_play - playback pcm device file name
	req_buf_size - ISO OUT endpoint request buffer size
	req_count - ISO OUT endpoint request count

The attributes have sane default values.

Testing the UAC1 function
-------------------------

device: run the gadget
host: aplay -l # should list our USB Audio Gadget

17. UAC2 function
=================

The function is provided by usb_f_uac2.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "uac2".
The uac2 function provides these attributes in its function directory:

	c_chmask - capture channel mask
	c_srate - capture sampling rate
	c_ssize - capture sample size (bytes)
	p_chmask - playback channel mask
	p_srate - playback sampling rate
	p_ssize - playback sample size (bytes)

The attributes have sane default values.

Testing the UAC2 function
-------------------------

device: run the gadget
host: aplay -l # should list our USB Audio Gadget

This function does not require real hardware support, it just
sends a stream of audio data to/from the host. In order to
actually hear something at the device side, a command similar
to this must be used at the device side:

$ arecord -f dat -t wav -D hw:2,0 | aplay -D hw:0,0 &

e.g.:

$ arecord -f dat -t wav -D hw:CARD=UAC2Gadget,DEV=0 | \
aplay -D default:CARD=OdroidU3

18. UVC function
================

The function is provided by usb_f_uvc.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "uvc".
The uvc function provides these attributes in its function directory:

	streaming_interval - interval for polling endpoint for data transfers
	streaming_maxburst - bMaxBurst for super speed companion descriptor
	streaming_maxpacket - maximum packet size this endpoint is capable of
			      sending or receiving when this configuration is
			      selected

There are also "control" and "streaming" subdirectories, each of which contain
a number of their subdirectories. There are some sane defaults provided, but
the user must provide the following:

	control header - create in control/header, link from control/class/fs
			and/or control/class/ss
	streaming header - create in streaming/header, link from
			streaming/class/fs and/or streaming/class/hs and/or
			streaming/class/ss
	format description - create in streaming/mjpeg and/or
			streaming/uncompressed
	frame description - create in streaming/mjpeg/<format> and/or in
			streaming/uncompressed/<format>

Each frame description contains frame interval specification, and each
such specification consists of a number of lines with an inverval value
in each line. The rules stated above are best illustrated with an example:

# mkdir functions/uvc.usb0/control/header/h
# cd functions/uvc.usb0/control/header/h
# ln -s header/h class/fs
# ln -s header/h class/ss
# mkdir -p functions/uvc.usb0/streaming/uncompressed/u/360p
# cat <<EOF > functions/uvc.usb0/streaming/uncompressed/u/360p/dwFrameInterval
666666
1000000
5000000
EOF
# cd $GADGET_CONFIGFS_ROOT
# mkdir functions/uvc.usb0/streaming/header/h
# cd functions/uvc.usb0/streaming/header/h
# ln -s ../../uncompressed/u
# cd ../../class/fs
# ln -s ../../header/h
# cd ../../class/hs
# ln -s ../../header/h
# cd ../../class/ss
# ln -s ../../header/h


Testing the UVC function
------------------------

device: run the gadget, modprobe vivid

# uvc-gadget -u /dev/video<uvc video node #> -v /dev/video<vivid video node #>

where uvc-gadget is this program:
http://git.ideasonboard.org/uvc-gadget.git

with these patches:
http://www.spinics.net/lists/linux-usb/msg99220.html

host: luvcview -f yuv

19. PRINTER function
====================

The function is provided by usb_f_printer.ko module.

Function-specific configfs interface
------------------------------------

The function name to use when creating the function directory is "printer".
The printer function provides these attributes in its function directory:

	pnp_string	- Data to be passed to the host in pnp string
	q_len		- Number of requests per endpoint

Testing the PRINTER function
----------------------------

The most basic testing:

device: run the gadget
# ls -l /devices/virtual/usb_printer_gadget/

should show g_printer<number>.

If udev is active, then /dev/g_printer<number> should appear automatically.

host:

If udev is active, then e.g. /dev/usb/lp0 should appear.

host->device transmission:

device:
# cat /dev/g_printer<number>
host:
# cat > /dev/usb/lp0

device->host transmission:

# cat > /dev/g_printer<number>
host:
# cat /dev/usb/lp0

More advanced testing can be done with the prn_example
described in Documentation/usb/gadget-printer.txt.