Re: [v7 2/4] ASoC: mediatek: mt8192: refactor for I2S3 DAI link of speaker

[Jiaxin Yu <jiaxin.yu@mediatek.com>]

On Wed, 2022-03-30 at 15:24 +0100, Mark Brown wrote:
> On Wed, Mar 30, 2022 at 10:06:24PM +0800, Jiaxin Yu wrote:
> > On Wed, 2022-03-30 at 13:30 +0100, Mark Brown wrote:
> > > Making a previously optional property required means that systems
> > > that
> > > previously worked may stop working unless they update their DT,
> > > DTs
> > > may
> > > be distributed separately to the kernel and perhaps even baked
> > > into
> > > firmware or similar.
> > Thank you for your detailed answer. I should keep the driver's
> > behavior
> > consistent with the description of dt-bindings. The "mediatek,hdmi-
> > codec" needs to be set as the required property. Is my
> > understanding
> > right?
> 
> The binding document and code should match so if one is changed the
> other needs to be changed too.
> 
> In theory we should never change a previously optional property to
> required which would mean that the code should be updated to reflect
> the
> binding document, however sometimes the DT isn't actually used as a
> stable intereface by anything for a given property or device type so
> we
> can get away with changing things.

"however sometimes the DT isn't actually used as a stable intereface by
anything for a given property or device type so we can get away with
changing things."

Sorry, I don't understand the real idea of this description. Does it
mean that dt-bindings in this series don't need to be updated, but the
driver?