[alsa-devel] [PATCH - seq 1/1] ALSA seq: expose the card number of ALSA seq clients

[Adam Goode]

On Fri, Jun 12, 2015 at 1:22 AM, Takashi Iwai <tiwai at suse.de> wrote:

> At Thu, 11 Jun 2015 23:43:53 -0400,
> Adam Goode wrote:
> >
> > On Mon, Jun 8, 2015 at 7:23 AM, Takashi Iwai <tiwai at suse.de> wrote:
> >
> > > At Thu,  4 Jun 2015 21:04:50 -0400,
> > > Adam Goode wrote:
> > > >
> > > > Expose the card number of seq clients. This allows interested
> userspace
> > > > programs to discover the hardware device that backs a particular seq
> > > > client. Before this change, the only way to get information about the
> > > > hardware for a client was by using brittle heuristics.
> > > >
> > > > Signed-off-by: Adam Goode <agoode at google.com>
> > >
> > > The patch looks almost good.  (One coding style fix about one-line if
> > > would be better, though.)
> > >
> > > However, if we want to have more changes, I'd prefer the protocol
> > > version bump after all changes are merged.
> > > Are you going to submit any further changes?
> > >
> > >
> > > thanks,
> > >
> > > Takashi
> > >
> >
> > Hi Takashi,
> >
> > I fixed up the patch in v2. It fixes the style issue and delays updating
> > protocol for now.
> >
> > I think there might be another useful field to expose (the hardware midi
> > device number), but I'm not sure yet. It is complicated since OPL3 does
> > expose a client but does not use rawmidi. Otherwise, the rawmidi device
> > number would be the obvious choice. I'm pretty sure I just need the card
> > number to solve my problems in Chrome, but I will have to think about it.
>
> IMO, we need to give the interface type (rawmidi, hwdep), too.  Then
> the client can open the device and query more detailed information.
>
>
Ah, that is a good idea. Let me prepare another patch with this extra
information.



> > The only other interesting change to make right now would be a tstamp
> field
> > (something like PCM), but it might be too complex for a quick fix. I do
> > like the PCM timestamp mode selection, and would like to see such a thing
> > in seq.
>
> Yeah, this one would be more intrusive changes.
>
>
Ok, I will defer this for now.


>
> thanks,
>
> Takashi
>

Thanks,

Adam