On Tue, Mar 03, 2020 at 11:59:30AM +0800, Shengjiu Wang wrote: > Hi > > On Tue, Mar 3, 2020 at 9:43 AM Rob Herring <robh@xxxxxxxxxx> wrote: > > > > On Sun, Mar 01, 2020 at 01:24:12PM +0800, Shengjiu Wang wrote: > > > asrc_format is more inteligent, which is align with the alsa > > > definition snd_pcm_format_t, we don't need to convert it to > > > format in driver, and it can distinguish S24_LE & S24_3LE. > > > > > > Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx> > > > --- > > > Documentation/devicetree/bindings/sound/fsl,asrc.txt | 4 +++- > > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > > > diff --git a/Documentation/devicetree/bindings/sound/fsl,asrc.txt b/Documentation/devicetree/bindings/sound/fsl,asrc.txt > > > index cb9a25165503..0cbb86c026d5 100644 > > > --- a/Documentation/devicetree/bindings/sound/fsl,asrc.txt > > > +++ b/Documentation/devicetree/bindings/sound/fsl,asrc.txt > > > @@ -38,7 +38,9 @@ Required properties: > > > > > > - fsl,asrc-rate : Defines a mutual sample rate used by DPCM Back Ends. > > > > > > - - fsl,asrc-width : Defines a mutual sample width used by DPCM Back Ends. > > > + - fsl,asrc-format : Defines a mutual sample format used by DPCM Back > > > + Ends. The value is one of SNDRV_PCM_FORMAT_XX in > > > + "include/uapi/sound/asound.h" > > > > You can't just change properties. They are an ABI. > > I have updated all the things related with this ABI in this patch series. > What else should I do? You probably should add one beside the old one. And all the existing drivers would have to continue to support "fsl,asrc-width", even if they start to support the new "fsl,asrc-format". The ground rule here is that a newer kernel should be able to work with an old DTB, IIRC. One more concern here is about the format value. Though I don't think those values, defined in asound.h, would be changed, yet I am not sure if it's legit to align DT bindings to a subsystem header file -- I only know that usually we keep shared macros under include/dt-bindings folder. I won't have any problem, if either Rob or Mark has no objection.
