On Mon, Mar 20, 2017 at 12:07 PM, Michael Zoran <mzoran@xxxxxxxxxxxx> wrote: > On Mon, 2017-03-20 at 11:50 -0500, Rob Herring wrote: >> On Sat, Mar 11, 2017 at 10:38:17PM -0800, Michael Zoran wrote: >> > Add documentation for the DMA properties required when using the >> > PWM controller of the bcm2835 for analog audio output. >> > >> > Signed-off-by: Michael Zoran <mzoran@xxxxxxxxxxxx> >> > --- >> > Documentation/devicetree/bindings/pwm/pwm-bcm2835.txt | 9 >> > ++++++++- >> > 1 file changed, 8 insertions(+), 1 deletion(-) >> > >> > diff --git a/Documentation/devicetree/bindings/pwm/pwm-bcm2835.txt >> > b/Documentation/devicetree/bindings/pwm/pwm-bcm2835.txt >> > index cf573e85b11d..08fc06fc083a 100644 >> > --- a/Documentation/devicetree/bindings/pwm/pwm-bcm2835.txt >> > +++ b/Documentation/devicetree/bindings/pwm/pwm-bcm2835.txt >> > @@ -1,14 +1,21 @@ >> > BCM2835 PWM controller (Raspberry Pi controller) >> > >> > Required properties: >> > -- compatible: should be "brcm,bcm2835-pwm" >> > +- compatible: should be "brcm,bcm2835-pwm" or "brcm,bcm2835- >> > analog-audio" >> >> Compatibles are not for selecting usage modes. You should describe >> the >> connection to the pwm that makes it an audio output rather than >> change >> the compatible. >> > > Cool, that's good to know that someone let me know after all this time. Well, there are more submitters than reviewers and maintainers and we have travel and vacation (aka lives). > And please tell how if DT nodes are an exact documentation of the > hardware how are virtualized DT nodes like firmware getting into the > DTs? DT is software's view of the hardware. Firmware provides interfaces to the OS just like a h/w device does. And just like h/w devices, the firmware is not discoverable and needs to be described. Originally, DT was the firmware's interface to the OS with OpenFirmware. Rob -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
