Fix empty midi input device list on linux

[kiselev-dv]

Resolves: #337844

Fix empty midi input device list on linux

Fix midi port capabilities for input ports (read instead of write)

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[Jojo-Schmitz]

I guess you mean https://musescore.org/en/node/337844 ;-)

[kiselev-dv]

I guess you mean https://musescore.org/en/node/337844 ;-)

Yep, did put a wrong issue number?

[Jojo-Schmitz]

Not really, just in the wrong format, as MuseScore.org issues don't turn into links, like GitHub issues do

[DmitryArefiev]

Tested on LinuxUbuntu 22.04.03 LTS. My Arturia KeyLab 61 Essential works fine.
But previously I didn't have a problems with connecting my MIDI keyboard to MS4. So I can't check the issue properly

@kiselev-dv Did you have a problem with MIDI keyboard before your changes?

[kiselev-dv]

Yes, I had my keyboard in midi output device list, but not in input devices.

aconnect -i
client 0: 'System' [type=kernel]
0 'Timer '
1 'Announce '
client 14: 'Midi Through' [type=kernel]
0 'Midi Through Port-0'
client 32: 'masterkey 49' [type=kernel,card=4]
0 'masterkey 49 MIDI 1'

This might be because higher end keyboards might also support midi playback so they would report write capabilities.

[kiselev-dv]

While I've being answering to @DmitryArefiev i took a look into midi output https://github.com/musescore/MuseScore/blob/master/src/framework/midi/internal/platform/lin/alsamidioutport.cpp#L77C67-L77C67 and I belive it should be SND_SEQ_PORT_CAP_SUBS_WRITE | SND_SEQ_PORT_CAP_WRITE; for output ports.

Should I change this as well?

[Eism]

@kiselev-dv
Yes, please

[DmitryArefiev]

Re-tested on LinuxUbuntu 22.04.03 LTS. My Arturia KeyLab 61 Essential works fine and available in MIDI Input/MIDI Output in Preferences>I/O