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diff --git a/Documentation/usb/gadget-testing.txt b/Documentation/usb/gadget-testing.txt new file mode 100644 index 000000000..5908a21fd --- /dev/null +++ b/Documentation/usb/gadget-testing.txt @@ -0,0 +1,819 @@ +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 (legacy implementation) +17. UAC2 function +18. UVC function +19. PRINTER function +20. UAC1 function (new API) + + +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 (legacy implementation) +================= + +The function is provided by usb_f_uac1_legacy.ko module. + +Function-specific configfs interface +------------------------------------ + +The function name to use when creating the function directory +is "uac1_legacy". +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) + req_number - the number of pre-allocated request for both capture + and playback + +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/ +# 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. + + +20. UAC1 function (virtual ALSA card, using u_audio API) +================= + +The function is provided by usb_f_uac1.ko module. +It will create a virtual ALSA card and the audio streams are simply +sinked to and sourced from it. + +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: + + 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) + req_number - the number of pre-allocated request for both capture + and playback + +The attributes have sane default values. + +Testing the UAC1 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=UAC1Gadget,DEV=0 | \ +aplay -D default:CARD=OdroidU3 |