Hi Rob,
Thanks a lot for your review!
On Tue, Apr 14, 2020 at 07:06:49PM -0500, Rob Herring wrote:
> On Mon, Apr 06, 2020 at 03:56:07PM +0200, Stephan Gerhold wrote:
> > The lpass-cpu driver now allows configuring the MI2S SD lines
> > by defining subnodes for one of the DAIs.
> >
> > Document this in the device tree bindings.
> >
> > Signed-off-by: Stephan Gerhold <stephan@xxxxxxxxxxx>
> > ---
> > .../bindings/sound/qcom,lpass-cpu.txt | 23 +++++++++++++++++++
> > 1 file changed, 23 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/sound/qcom,lpass-cpu.txt b/Documentation/devicetree/bindings/sound/qcom,lpass-cpu.txt
> > index 21c648328be9..df53a10502f7 100644
> > --- a/Documentation/devicetree/bindings/sound/qcom,lpass-cpu.txt
> > +++ b/Documentation/devicetree/bindings/sound/qcom,lpass-cpu.txt
> > @@ -30,6 +30,8 @@ Required properties:
> > - reg : Must contain an address for each entry in reg-names.
> > - reg-names : A list which must include the following entries:
> > * "lpass-lpaif"
> > +- #address-cells : Must be 1
> > +- #size-cells : Must be 0
> >
> >
> >
> > @@ -37,6 +39,18 @@ Optional properties:
> >
> > - qcom,adsp : Phandle for the audio DSP node
> >
> > +By default, the driver uses up to 4 MI2S SD lines, for a total of 8 channels.
> > +The SD lines to use can be configured by adding subnodes for each of the DAIs.
> > +
> > +Required properties for each DAI (represented by a subnode):
> > +- reg : Must be one of the DAI IDs
> > + (usually part of dt-bindings header)
> > +- qcom,playback-sd-lines: List of serial data lines (0-3) to use for playback
>
> 0-3 for the values or number of entries?
>
It's basically a list of bits, e.g. <0 1> or <1 2 3> where the bits are
0-3. Number of entries would be 1-4. I will clarify this a bit in the
next version.
> > +- qcom,capture-sd-lines : List of serial data lines (0-3) to use for capture
> > +
> > +Note that adding a subnode changes the default to "no lines configured",
> > +so both playback and capture lines should be configured when a subnode is added.
> > +
> > Example:
> >
> > lpass@28100000 {
> > @@ -51,4 +65,13 @@ lpass@28100000 {
> > reg = <0x28100000 0x10000>;
> > reg-names = "lpass-lpaif";
> > qcom,adsp = <&adsp>;
> > +
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > +
> > + /* Optional to set different MI2S SD lines */
> > + mi2s-quaternary@3 {
>
> Normally the node name reflects the class of device. IOW, all the child
> nodes should have the same name.
>
Given that I somewhat adapted these node names from existing bindings
at Documentation/devicetree/bindings/sound/qcom,q6afe.txt,
I have sent out two patches to change them there first:
https://lore.kernel.org/linux-devicetree/20200415081159.1098-1-stephan@xxxxxxxxxxx/
Maybe you can take a look at the new node names there first,
and if they are fine I will send an updated version of this patch set.
Thanks,
Stephan
> > + reg = <MI2S_QUATERNARY>;
> > + qcom,playback-sd-lines = <0 1>;
> > + };
> > };
> > --
> > 2.26.0
> >
