Re: [PATCH v7 1/3] media: dt-bindings: ov8856: Document YAML bindings

From: Robert Foss
Date: Mon Apr 27 2020 - 11:13:58 EST

On Wed, 15 Apr 2020 at 18:21, Marco Felsch <m.felsch@xxxxxxxxxxxxxx> wrote:
>
> On 20-04-15 11:07, Rob Herring wrote:
> > On Wed, Apr 08, 2020 at 01:08:14PM +0200, Robert Foss wrote:
> > > From: Dongchun Zhu <dongchun.zhu@xxxxxxxxxxxx>
> > >
> > > This patch adds documentation of device tree in YAML schema for the
> > > OV8856 CMOS image sensor.
> > >
> > > Signed-off-by: Dongchun Zhu <dongchun.zhu@xxxxxxxxxxxx>
> > > Signed-off-by: Robert Foss <robert.foss@xxxxxxxxxx>
> > > ---
> > >
> > > - Changes since v6:
> > > * Marco: remove qcom specifics from DT example
> > >
> > > - Changes since v5:
> > > * Add assigned-clocks and assigned-clock-rates
> > > * robher: dt-schema errors
> > >
> > > - Changes since v4:
> > > * Fabio: Change reset-gpio to GPIO_ACTIVE_LOW, explain in description
> > > * Add clock-lanes property to example
> > > * robher: Fix syntax error in devicetree example
> > >
> > > - Changes since v3:
> > > * robher: Fix syntax error
> > > * robher: Removed maxItems
> > > * Fixes yaml 'make dt-binding-check' errors
> > >
> > > - Changes since v2:
> > > Fixes comments from from Andy, Tomasz, Sakari, Rob.
> > > * Convert text documentation to YAML schema.
> > >
> > > - Changes since v1:
> > > Fixes comments from Sakari, Tomasz
> > > * Add clock-frequency and link-frequencies in DT
> > >
> > > .../devicetree/bindings/media/i2c/ov8856.yaml | 143 ++++++++++++++++++
> > > MAINTAINERS | 1 +
> > > 2 files changed, 144 insertions(+)
> > > create mode 100644 Documentation/devicetree/bindings/media/i2c/ov8856.yaml
> > >
> > > diff --git a/Documentation/devicetree/bindings/media/i2c/ov8856.yaml b/Documentation/devicetree/bindings/media/i2c/ov8856.yaml
> > > new file mode 100644
> > > index 000000000000..96bef5403d7e
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/media/i2c/ov8856.yaml
> > > @@ -0,0 +1,143 @@
> > > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> > > +# Copyright (c) 2019 MediaTek Inc.
> > > +%YAML 1.2
> > > +---
> > > +$id: http://devicetree.org/schemas/media/i2c/ov8856.yaml#
> > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > +
> > > +title: Omnivision OV8856 CMOS Sensor Device Tree Bindings
> > > +
> > > +maintainers:
> > > + - Ben Kao <ben.kao@xxxxxxxxx>
> > > + - Dongchun Zhu <dongchun.zhu@xxxxxxxxxxxx>
> > > +
> > > +description: |-
> > > + The Omnivision OV8856 is a high performance, 1/4-inch, 8 megapixel, CMOS
> > > + image sensor that delivers 3264x2448 at 30fps. It provides full-frame,
> > > + sub-sampled, and windowed 10-bit MIPI images in various formats via the
> > > + Serial Camera Control Bus (SCCB) interface. This chip is programmable
> > > + through I2C and two-wire SCCB. The sensor output is available via CSI-2
> > > + serial data output (up to 4-lane).
> > > +
> > > +properties:
> > > + compatible:
> > > + const: ovti,ov8856
> > > +
> > > + reg:
> > > + maxItems: 1
> > > +
> > > + clocks:
> > > + maxItems: 1
> > > +
> > > + clock-names:
> > > + description:
> > > + Input clock for the sensor.
> > > + items:
> > > + - const: xvclk
> > > +
> > > + assigned-clocks:
> > > + description:
> > > + Input clock for the sensor.
> > > +
> > > + assigned-clock-rates:
> > > + description:
> > > + Frequency of the xvclk clock in Hertz.
> >
> > These 2 should have a 'maxItems: 1'
>
> Don't know why those properties are needed here.. IMHO this shouldn't be
> part of the binding or at least it should be optional and not required.
> All we need is the clocks and the clock-names property.

Thanks Marco, I'll make it optional for the next revision.

>
> > > + dovdd-supply:
> > > + description:
> > > + Definition of the regulator used as interface power supply.
> > > +
> > > + avdd-supply:
> > > + description:
> > > + Definition of the regulator used as analog power supply.
> > > +
> > > + dvdd-supply:
> > > + description:
> > > + Definition of the regulator used as digital power supply.
> > > +
> > > + reset-gpios:
> > > + description:
> > > + The phandle and specifier for the GPIO that controls sensor reset.
> > > + This corresponds to the hardware pin XSHUTDOWN which is physically
> > > + active low.
> > > +
> > > + port:
> > > + type: object
> > > + additionalProperties: false
> > > + description:
> > > + A node containing input and output port nodes with endpoint definitions
> >
> > Only an output, right?
> >
> > > + as documented in
> > > + Documentation/devicetree/bindings/media/video-interfaces.txt
> > > +
> > > + properties:
> > > + endpoint:
> > > + type: object
> > > +
> > > + properties:
> > > + clock-lanes:
> > > + maxItems: 1
> > > +
> > > + data-lanes:
> > > + maxItems: 1
> > > +
> > > + remote-endpoint: true
> > > +
> > > + required:
> > > + - clock-lanes
> > > + - data-lanes
> > > + - remote-endpoint
> > > +
> > > + required:
> > > + - endpoint
> > > +
> > > +required:
> > > + - compatible
> > > + - reg
> > > + - clocks
> > > + - clock-names
> > > + - assigned-clocks
> > > + - assigned-clock-rates
> > > + - dovdd-supply
> > > + - avdd-supply
> > > + - dvdd-supply
> > > + - reset-gpios
> > > + - port
> > > +
> > > +additionalProperties: false
> > > +
> > > +examples:
> > > + - |
> > > + #include <dt-bindings/gpio/gpio.h>
> > > +
> > > + i2c {
> > > + #address-cells = <1>;
> > > + #size-cells = <0>;
> > > +
> > > + ov8856: camera@10 {
> > > + compatible = "ovti,ov8856";
> > > + reg = <0x10>;
> > > +
> > > + reset-gpios = <&pio 111 GPIO_ACTIVE_LOW>;
> > > + pinctrl-names = "default";
> > > + pinctrl-0 = <&clk_24m_cam>;
> > > +
> > > + clocks = <&cam_osc>;
> > > + clock-names = "xvclk";
> > > + assigned-clocks = <&cam_osc>;
> > > + assigned-clock-rates = <19200000>;
> > > +
> > > + avdd-supply = <&mt6358_vcama2_reg>;
> > > + dvdd-supply = <&mt6358_vcamd_reg>;
> > > + dovdd-supply = <&mt6358_vcamio_reg>;
> > > +
> > > + port {
> > > + wcam_out: endpoint {
> > > + remote-endpoint = <&mipi_in_wcam>;
> > > + clock-lanes = <0>;
> > > + data-lanes = <1 2 3 4>;
> > > + link-frequencies = /bits/ 64 <360000000 180000000>;
> > > + };
> > > + };
> > > + };
> > > + };
> > > +...
> > > \ No newline at end of file
> >
> > ^^^
> >
> > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > index 534a8dc4f84a..3f35c6e9700a 100644
> > > --- a/MAINTAINERS
> > > +++ b/MAINTAINERS
> > > @@ -12465,6 +12465,7 @@ L: linux-media@xxxxxxxxxxxxxxx
> > > T: git git://linuxtv.org/media_tree.git
> > > S: Maintained
> > > F: drivers/media/i2c/ov8856.c
> > > +F: Documentation/devicetree/bindings/media/i2c/ov8856.yaml
> > >
> > > OMNIVISION OV9650 SENSOR DRIVER
> > > M: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> > > --
> > > 2.25.1
> > >
> >
>
> --
> Pengutronix e.K. | |
> Steuerwalder Str. 21 | http://www.pengutronix.de/ |
> 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
> Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |