Re: [PATCH] ASoC: qdsp6: q6apm: use dai link pcm id as pcm device number

From: Greg KH
Date: Thu Jun 29 2023 - 13:23:09 EST


On Thu, Jun 29, 2023 at 05:16:44PM +0100, Mark Brown wrote:
> On Thu, Jun 29, 2023 at 06:06:05PM +0200, Greg KH wrote:
> > On Thu, Jun 29, 2023 at 04:43:57PM +0100, Mark Brown wrote:
>
> > > Won't this be an ABI change? That seems like it'd disrupt things in
> > > stable.
>
> > ABI changes should disrupt things just the same in Linus's tree, why is
> > stable any different?
>
> This is a numbering resulting from enumeration thing so it gets to be
> like the issues we've had with the order in which block and ethernet
> devices appear, it's on the edge the extent to which people might be
> relying on it. If it's causing some problem as is and there's a reason
> to do something (see the first half of my reply...) but the case gets
> even harder to make with stable.

It shouldn't matter for stable or not, if the change is acceptable in
Linus's tree, with the userspace visable change, then it should be
acceptable in any active stable branch as well. There is no difference
here for userspace api/abi rules.

thanks,

greg k-h