On Thu, Apr 09, 2020 at 09:03:28PM +0800, Dongchun Zhu wrote: > Hi Mauro, Sakari, Rob, > > On Wed, 2020-04-08 at 14:49 +0200, Tomasz Figa wrote: > > On Tue, Dec 17, 2019 at 4:15 AM Tomasz Figa <tfiga@xxxxxxxxxxxx> wrote: > > > > > > Hi Rob, Dongchun, > > > > > > On Wed, Dec 11, 2019 at 8:29 PM Dongchun Zhu <dongchun.zhu@xxxxxxxxxxxx> wrote: > > > > > > > > Add DT bindings documentation for Omnivision OV02A10 image sensor. > > > > > > > > Reviewed-by: Rob Herring <robh@xxxxxxxxxx> > > > > Signed-off-by: Dongchun Zhu <dongchun.zhu@xxxxxxxxxxxx> > > > > --- > > > > .../devicetree/bindings/media/i2c/ov02a10.txt | 54 ++++++++++++++++++++++ > > > > MAINTAINERS | 7 +++ > > > > 2 files changed, 61 insertions(+) > > > > create mode 100644 Documentation/devicetree/bindings/media/i2c/ov02a10.txt > > > > > > > > diff --git a/Documentation/devicetree/bindings/media/i2c/ov02a10.txt b/Documentation/devicetree/bindings/media/i2c/ov02a10.txt > > > > new file mode 100644 > > > > index 0000000..18acc4f > > > > --- /dev/null > > > > +++ b/Documentation/devicetree/bindings/media/i2c/ov02a10.txt > > > > @@ -0,0 +1,54 @@ > > > > +* Omnivision OV02A10 MIPI CSI-2 sensor > > > > + > > > > +Required Properties: > > > > +- compatible: shall be "ovti,ov02a10" > > > > +- clocks: reference to the eclk input clock > > > > +- clock-names: shall be "eclk" > > > > +- dovdd-supply: Digital I/O voltage supply, 1.8 volts > > > > +- avdd-supply: Analog voltage supply, 2.8 volts > > > > +- dvdd-supply: Digital core voltage supply, 1.8 volts > > > > +- powerdown-gpios: reference to the GPIO connected to the powerdown pin, > > > > + if any. This is an active low signal to the OV02A10. > > > > > > On the hardware level this pin is active high, i.e. the device is > > > powered down when the signal is high. > > > > > > > +- reset-gpios: reference to the GPIO connected to the reset pin, if any. > > > > + This is an active high signal to the OV02A10. > > > > > > On the hardware level this pin is active low, i.e. the device is held > > > in reset when the signal is low. > > > > > > However, there is some confusion around how the polarity flag in the > > > GPIO specifier is supposed to be used. > > > > > > As per [1], > > > > > > "The gpio-specifier's polarity flag should represent the physical > > > level at the GPIO controller that achieves (or represents, for inputs) > > > a logically asserted value at the device. The exact definition of > > > logically asserted should be defined by the binding for the device." > > > > > > In this case it sounds like "logically asserted" means the device is > > > powered down or held in reset, respectively, which would suggest that > > > the specifiers should have GPIO_ACTIVE_HIGH and GPIO_ACTIVE_LOW > > > respectively. The latter would cause the GPIO subsystem to invert the > > > values set by the consumers, which would then be confusing from the > > > driver implementation point of view. > > > > > > Should the pin be renamed to "nreset"? It would change the meaning of > > > "logically asserted" to "device is not held in reset" and so > > > GPIO_ACTIVE_HIGH (or 0) would be the right value to use. > > > > > > [1] https://elixir.bootlin.com/linux/latest/source/Documentation/devicetree/bindings/gpio/gpio.txt#L83 > > > > + Bartosz, Linus, Sakari and the linux-gpio ML for a broader audience. > > > > Would appreciate some feedback on what's the proper way of defining > > GPIO polarity. Thanks! > > > > Best regards, > > Tomasz > > > > I have another question about OV02A10 CMOS sensor dt-binding. > As its text documentation was already reviewed by Rob on earlier > version: > https://patchwork.linuxtv.org/patch/59787/ > I wonder whether we need to convert it to DT in YAML. Yes. > In fact, I just submitted one conversion version. > https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/2143922 > > Unluckily make dt_binding_check still report errors temporarily. > It seems there is something wrong with the port property in DT. > Could anyone help provide some tips? > $make dt_binding_check > DT_SCHEMA_FILES=Documentation/devicetree/bindings/media/i2c/ovti,ov02a10.yaml > SCHEMA Documentation/devicetree/bindings/processed-schema.yaml > Documentation/devicetree/bindings/media/i2c/ovti,ov02a10.yaml: ignoring, > error in schema: properties: port: patternProperties: endpoint > warning: no schema found in file: > Documentation/devicetree/bindings/media/i2c/ovti,ov02a10.yaml > make[2]: *** [Documentation/devicetree/bindings/processed-schema.yaml] > Error 255 > make[1]: *** [dt_binding_check] Error 2 > make: *** [sub-make] Error 2 patternProperties: endpoint: type: object additionalProperties: false You need more indentation under 'endpoint'. Also, 'endpoint' is a fixed string, so it should be under 'properties' rather than 'patternProperties'. > > In addition, as OV02A10 use one private property to distinguish > different projects that adopting different register settings, > I would appreciate the feedback on how to add private property to DT in > YAML. Like any other property. Submit something for review. Rob
