diff options
| author | Takashi Iwai <tiwai@suse.de> | 2023-07-25 08:22:05 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-07-26 06:38:14 +0200 |
| commit | 1b437d2fb3c1a8c7f2a8a096c0871c8e7c8d109e (patch) | |
| tree | ec3069add00a08176aebe820a9c2dade79b2b913 /Documentation/usb | |
| parent | 8559caa985503d057e55dd7c6362b8f98359ba2e (diff) | |
usb: gadget: midi2: Add "Operation Mode" control
Add a new ALSA control element to watch the current operation mode
(MIDI 1.0 or MIDI 2.0). It's a read-only control that reflects the
current value of altsetting, and 0 means unused, 1 for MIDI 1.0
(altset 0) and 2 for MIDI 2.0 (altset 1).
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20230725062206.9674-7-tiwai@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation/usb')
| -rw-r--r-- | Documentation/usb/gadget-testing.rst | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/Documentation/usb/gadget-testing.rst b/Documentation/usb/gadget-testing.rst index 0f3708ae5bc8..1fb181d61322 100644 --- a/Documentation/usb/gadget-testing.rst +++ b/Documentation/usb/gadget-testing.rst @@ -1106,3 +1106,14 @@ On the host:: The access to MIDI 1.0 on altset 0 on the host is supported, and it's translated from/to UMP packets on the gadget. It's bound to only Function Block 0. + +The current operation mode can be observed in ALSA control element +"Operation Mode" for SND_CTL_IFACE_RAWMIDI. For example:: + + $ amixer -c1 contents + numid=1,iface=RAWMIDI,name='Operation Mode' + ; type=INTEGER,access=r--v----,values=1,min=0,max=2,step=0 + : values=2 + +where 0 = unused, 1 = MIDI 1.0 (altset 0), 2 = MIDI 2.0 (altset 1). +The example above shows it's running in 2, i.e. MIDI 2.0. |