[alsa-devel] [PATCH] Provide card number / PID via sequencer client info

[Clemens Ladisch]

Takashi Iwai wrote:
> Martin Koegler wrote:
>> On Mon, Feb 15, 2016 at 11:34:09PM +0100, Takashi Iwai wrote:
>>>> On Mon, Feb 15, 2016 at 08:08:12PM +0100, Takashi Iwai wrote:
>>>>> Well, the question is whether only card number is enough.  What if
>>>>> cards provide multiple rawmidi devices?
>>>>
>>>> Aren't they currently ports?
>>>> seq_midi.c creates just one sequencer device per card number.
>>>
>>> Look at cards with synth support, e.g. emu10k1 or OPL3/OPL4.

Or snd-virmidi.

>> Should I export the client_index parameter of snd_seq_create_kernel_client too?
>
> Well, I'd rather ask what are the requirements -- in wide ranges.

The original requirement was just the ability to get the card name.

> As you already noticed, multiple rawmidi devices and rawmidi
> subdevices are mapped into a single client with various ports.

Actually, multiple devices get multiple clients.

> And, as mentioned, some cards provide indeed multiple clients.  How do
> you identify which client is for what?  So far, it's identified only
> from the name string and the type bits of each port.  Isn't it enough?
> If not, what have to be provided?

This patch is about the card.  If we really need a method to identify
the device, we can still add it later -- this patch does not obstruct
such an extension.


Regards,
Clemens