[alsa-devel] [RFC][PATCH] fall back to reserved minor numbers
tiwai at suse.de
Fri May 14 10:59:34 CEST 2010
At Fri, 14 May 2010 16:55:26 +0800,
Wu Fengguang wrote:
> On Fri, May 14, 2010 at 04:17:27PM +0800, Takashi Iwai wrote:
> > At Fri, 14 May 2010 11:28:28 +0800,
> > Wu Fengguang wrote:
> > >
> > > When the static minor numbers collide because of too many devices,
> > > fall back to the reserved minor numbers 2 and 3.
> > >
> > > This for example will allow Intel HDMI audio driver to create three PCM
> > > devices (index 3, 7, 8; the minor number of the last index will
> > > otherwise collide with the first record device).
> > >
> > > The other option is to force enable CONFIG_SND_DYNAMIC_MINORS.
> > >
> > > Signed-off-by: Wu Fengguang <fengguang.wu at intel.com>
> > Well, frankly, I don't see a big merit of doing this.
> > Most (all?) 2.6-based distros are using udev, thus
> > CONFIG_SND_DYNAMIC_MINORS should be used there. The rest is for old
> > distros or for some limited systems like embedded devices, and they
> > won't need so much PCM devices.
> > Even if we do this, it doesn't make sense unless the user-space side
> > creates the corresponding device node.
> I was afraid of this case: an embedded system with G45 HDMI codec.
> This codec only has 1 PCM playback device, however the driver still
> requires enabling CONFIG_SND_DYNAMIC_MINORS in order to support more
> capable HDMI codecs.
It's 2.6 kernel and no udev? It must be a rare case.
In such a case, they can patch it out by themselves.
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