On Mon, 05 Dec 2016, Thierry Reding wrote: > On Fri, Dec 02, 2016 at 11:17:18AM +0100, Benjamin Gaignard wrote: > > Define bindings for pwm-stm32 > > > > version 2: > > - use parameters instead of compatible of handle the hardware configuration > > > > Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxx> > > --- > > .../devicetree/bindings/pwm/pwm-stm32.txt | 38 ++++++++++++++++++++++ > > 1 file changed, 38 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/pwm/pwm-stm32.txt > > > > diff --git a/Documentation/devicetree/bindings/pwm/pwm-stm32.txt b/Documentation/devicetree/bindings/pwm/pwm-stm32.txt > > new file mode 100644 > > index 0000000..575b9fb > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/pwm/pwm-stm32.txt > > @@ -0,0 +1,38 @@ > > +STMicroelectronics PWM driver bindings for STM32 > > Technically this bindings describe devices, so "driver binding" is a > somewhat odd wording. Perhaps: > > STMicroelectronics STM32 General Purpose Timer PWM bindings > > ? > > > + > > +Must be a sub-node of STM32 general purpose timer driver > > +Parent node properties are describe in ../mfd/stm32-general-purpose-timer.txt > > Again, "driver parent node" is odd. Perhaps: > > Must be a sub-node of an STM32 General Purpose Timer device tree > node. See ../mfd/stm32-general-purpose-timer.txt for details about > the parent node. > > ? > > > +Required parameters: > > +- compatible: Must be "st,stm32-pwm" > > +- pinctrl-names: Set to "default". > > +- pinctrl-0: List of phandles pointing to pin configuration nodes > > + for PWM module. > > + For Pinctrl properties, please refer to [1]. > > Your indentation and capitalization are inconsistent. Also, please refer > to the pinctrl bindings by relative path and inline, rather than as a > footnote reference. > > > + > > +Optional parameters: > > +- st,breakinput: Set if the hardware have break input capabilities > > +- st,breakinput-polarity: Set break input polarity. Default is 0 > > + The value define the active polarity: > > + - 0 (active LOW) > > + - 1 (active HIGH) > > Could we fold these into a single property? If st,breakinput-polarity is > not present it could simply mean that there is no break input, and if it > is present you don't have to rely on a default. > > > +- st,pwm-num-chan: Number of available PWM channels. Default is 0. > > The pwm- prefix is rather redundant since the node is already named pwm. > Why not simply st,channels? Or simply channels, since it's not really > anything specific to this hardware. > > Come to think of it, might be worth having a discussion with our DT > gurus about what their stance is on using the # as prefix for numbers > (such as in #address-cells or #size-cells). This could be #channels to > mark it more explicitly as representing a count. Unfortunately that ship has sailed. st,pwm-num-chan already exists (with your blessing). It's usually suggested to reuse exiting properties when writing new bindings. > > +- st,32bits-counter: Set if the hardware have a 32 bits counter > > +- st,complementary: Set if the hardware have complementary output channels > > "hardware has" and also maybe mention explicitly that this is a boolean > property. Otherwise people might be left wondering what it should be set > to. Or maybe word this differently to imply that it's boolean: > > - st,32bits-counter: if present, the hardware has a 32 bit counter > - st,complementary: if present, the hardware has a complementary > output channel > > Thierry -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog -- 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
