On 25 March 2024 22:23:08 GMT, Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> wrote: >On Mon, Mar 25, 2024 at 10:56:44PM +0200, Laurent Pinchart wrote: >> On Mon, Mar 25, 2024 at 08:48:57PM +0000, Jonathan Cameron wrote: >> > On Mon, 25 Mar 2024 22:32:41 +0200 Laurent Pinchart wrote: >> > >> > > The DAC081C081 is a TI DAC whose software interface is compatible with >> > > the DAC5571. It is the 8-bit version of the DAC121C081, already >> > > supported by the DAC5571 bindings. Extends the bindings to support this >> > > chip. >> > > >> > > Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> >> > >> > Hi Laurent, >> > >> > Given it's a part number where no one is going to guess it is compatible >> > with the DAC5571 and that we don't have a history of fallback compatibles >> > I'm fine with this change, but just wanted to ask is a fallback compatible >> > useful to you to run with older kernels? >> > >> > I should have noticed when Peter added the dac121c081. If we add a fallback >> > should do that one as well. >> >> I've indeed noticed that there should have been a fallback for >> dac121c081, but didn't stop to ponder why that wasn't the case, and just >> went along with the flow :-) I agree a fallback could be useful, which >> would then allow dropping patch 2/5 from this series (*). I can do so if >> you prefer. > >And in that case, should I first introduce support in the bindings for >"ti,dac121c081", "ti,dac7571" and deprecate usage of "ti,dac121c081" >alone ? Yes. Not sure if we need an explicit binding entry for deprecated version... > >> * This is not entirely true. While the DAC1081C081 is largely compatible >> with the DAC5573, they have different values for one of the power-down >> resistors (2.5kΩ instead of 1kΩ if I recall correctly). To be completely >> accurate, the driver should report that. We could still use the fallback >> compatible, reporting the wrong power-down resistor value. >> >> > > --- >> > > Documentation/devicetree/bindings/iio/dac/ti,dac5571.yaml | 1 + >> > > 1 file changed, 1 insertion(+) >> > > >> > > diff --git a/Documentation/devicetree/bindings/iio/dac/ti,dac5571.yaml b/Documentation/devicetree/bindings/iio/dac/ti,dac5571.yaml >> > > index 79da0323c327..e59db861e2eb 100644 >> > > --- a/Documentation/devicetree/bindings/iio/dac/ti,dac5571.yaml >> > > +++ b/Documentation/devicetree/bindings/iio/dac/ti,dac5571.yaml >> > > @@ -21,6 +21,7 @@ properties: >> > > - ti,dac5573 >> > > - ti,dac6573 >> > > - ti,dac7573 >> > > + - ti,dac081c081 >> > > - ti,dac121c081 >> > > >> > > reg: >
