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. 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 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. > > > > Best regards, > > Tomasz > > > > > + > > > +Optional Properties: > > > +- rotation: as defined in > > > + Documentation/devicetree/bindings/media/video-interfaces.txt, > > > + valid values are 0 (sensor mounted upright) and 180 (sensor > > > + mounted upside down). > > > + > > > +The device node shall contain one 'port' child node with an > > > +'endpoint' subnode for its digital output video port, > > > +in accordance with the video interface bindings defined in > > > +Documentation/devicetree/bindings/media/video-interfaces.txt. > > > + > > > +Example: > > > +&i2c4 { > > > + ov02a10: camera-sensor@3d { > > > + compatible = "ovti,ov02a10"; > > > + reg = <0x3d>; > > > + pinctrl-names = "default"; > > > + pinctrl-0 = <&camera_pins_cam1_mclk_on>; > > > + > > > + clocks = <&topckgen CLK_TOP_MUX_CAMTG2>, > > > + <&topckgen CLK_TOP_UNIVP_192M_D8>; > > > + clock-names = "eclk", "freq_mux"; > > > + clock-frequency = <24000000>; > > > + > > > + dovdd-supply = <&mt6358_vcamio_reg>; > > > + avdd-supply = <&mt6358_vcama1_reg>; > > > + dvdd-supply = <&mt6358_vcn18_reg>; > > > + powerdown-gpios = <&pio 107 GPIO_ACTIVE_LOW>; > > > + reset-gpios = <&pio 109 GPIO_ACTIVE_HIGH>; > > > + rotation = <180>; > > > + > > > + port { > > > + /* MIPI CSI-2 bus endpoint */ > > > + ov02a10_core: endpoint { > > > + remote-endpoint = <&ov02a10_0>; > > > + link-frequencies = /bits/ 64 <390000000>; > > > + }; > > > + }; > > > + }; > > > +}; > > > diff --git a/MAINTAINERS b/MAINTAINERS > > > index bd5847e..92a868c 100644 > > > --- a/MAINTAINERS > > > +++ b/MAINTAINERS > > > @@ -12130,6 +12130,13 @@ T: git git://linuxtv.org/media_tree.git > > > S: Maintained > > > F: drivers/media/i2c/ov13858.c > > > > > > +OMNIVISION OV02A10 SENSOR DRIVER > > > +M: Dongchun Zhu <dongchun.zhu@xxxxxxxxxxxx> > > > +L: linux-media@xxxxxxxxxxxxxxx > > > +T: git git://linuxtv.org/media_tree.git > > > +S: Maintained > > > +F: Documentation/devicetree/bindings/media/i2c/ov02a10.txt > > > + > > > OMNIVISION OV2680 SENSOR DRIVER > > > M: Rui Miguel Silva <rmfrfs@xxxxxxxxx> > > > L: linux-media@xxxxxxxxxxxxxxx > > > -- > > > 2.9.2
