[v2,2/5] dt-bindings: media: document SK Hynix Hi-846 MIPI CSI-2 8M pixel sensor

  Document the bindings used for the SK Hynix Hi-846 CMOS camera driver.

Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
---
 .../bindings/media/i2c/hynix,hi846.yaml       | 99 +++++++++++++++++++
 1 file changed, 99 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
  

Hi Martin,

Thank you for the patch.

On Fri, May 28, 2021 at 10:13:33AM +0200, Martin Kepplinger wrote:
> Document the bindings used for the SK Hynix Hi-846 CMOS camera driver.
> 
> Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
> ---
>  .../bindings/media/i2c/hynix,hi846.yaml       | 99 +++++++++++++++++++
>  1 file changed, 99 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> 
> diff --git a/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml b/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> new file mode 100644
> index 000000000000..2991108e23e5
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> @@ -0,0 +1,99 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/media/i2c/hynix,hi846.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: SK Hynix Hi-846 1/4" 8M Pixel MIPI CSI-2 sensor
> +
> +maintainers:
> +  - Martin Kepplinger <martin.kepplinger@puri.sm>
> +
> +description: |-
> +  The Hi-846 is a raw image sensor with an MIPI CSI-2 image data
> +  interface and CCI (I2C compatible) control bus. The output format
> +  is 10bit Bayer.
> +
> +properties:
> +  compatible:
> +    const: hynix,hi846
> +
> +  reg:
> +    description: I2C device address.

You can drop the description, it's implicit that reg is the I2C address
for I2C devices.

> +    maxItems: 1
> +
> +  clocks:
> +    description: Reference to the mclk clock.
> +    maxItems: 1

You could also write this

  clocks:
    items:
      - description: Reference to the mclk clock.

The maxItems will then be implicit. This is the preferred form when
multiple clocks are used, and given that clocks it meant to contain a
list of clocks, even if it has a single entry, placing the description
in a list of items may be a bit better semantically speaking.

> +
> +  clock-names:
> +    const: mclk

Similarly,

  clock-names:
    items:
      - const: mclk

Rob, is standardizing this pattern a good idea, or do you prefer the
shorter form

  clock-names:
    const: mclk

> +
> +  rst-gpios:

We try to standardize GPIO names, so let's use reset-gpios.

> +    description: Reference to the GPIO connected to the reset pin. Active low.
> +    maxItems: 1
> +
> +  vdd-supply:
> +    description: Definition of the regulator used as 1.8V digital power supply.
> +
> +  port:
> +    $ref: /schemas/graph.yaml#/properties/port
> +    additionalProperties: false
> +
> +    properties:
> +      endpoint:
> +        $ref: /schemas/media/video-interfaces.yaml#
> +        unevaluatedProperties: false
> +
> +        properties:
> +          data-lanes:
> +            oneOf:
> +              - items:
> +                  - const: 1
> +                  - const: 2
> +                  - const: 3
> +                  - const: 4
> +              - items:
> +                  - const: 1
> +                  - const: 2
> +
> +        required:
> +          - data-lanes
> +
> +required:
> +  - compatible
> +  - reg
> +  - clocks
> +  - clock-names
> +  - rst-gpios
> +  - vdd-supply
> +  - port
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        hi846: camera@20 {
> +            compatible = "hynix,hi846";
> +            reg = <0x20>;
> +            clocks = <&clk>;
> +            clock-names = "mclk";
> +            vdd-supply = <&reg_camera_pwr_en>; /* 1.8v */
> +            rst-gpios = <&gpio1 25 GPIO_ACTIVE_LOW>;
> +
> +            port {
> +                camera_out: endpoint {
> +                    remote-endpoint = <&csi1_ep1>;
> +                    data-lanes = <1 2>;
> +                };
> +            };
> +        };
> +    };
> +
> +...
  

Hi Martin,

On Fri, May 28, 2021 at 10:13:33AM +0200, Martin Kepplinger wrote:
> Document the bindings used for the SK Hynix Hi-846 CMOS camera driver.
> 
> Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>

Could you read Documentation/driver-api/media/camera-sensor.rst, please?

I believe you'll need assigned-clock-rates device property as well as
link-frequencies endpoint property.

> ---
>  .../bindings/media/i2c/hynix,hi846.yaml       | 99 +++++++++++++++++++
>  1 file changed, 99 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> 
> diff --git a/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml b/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> new file mode 100644
> index 000000000000..2991108e23e5
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> @@ -0,0 +1,99 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/media/i2c/hynix,hi846.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: SK Hynix Hi-846 1/4" 8M Pixel MIPI CSI-2 sensor
> +
> +maintainers:
> +  - Martin Kepplinger <martin.kepplinger@puri.sm>
> +
> +description: |-
> +  The Hi-846 is a raw image sensor with an MIPI CSI-2 image data
> +  interface and CCI (I2C compatible) control bus. The output format
> +  is 10bit Bayer.

Virtually all Bayer sensors can do 8 bpp, too. I'd drop the sentence
mentoning 10 bits.

> +
> +properties:
> +  compatible:
> +    const: hynix,hi846
> +
> +  reg:
> +    description: I2C device address.
> +    maxItems: 1
> +
> +  clocks:
> +    description: Reference to the mclk clock.
> +    maxItems: 1
> +
> +  clock-names:
> +    const: mclk
> +
> +  rst-gpios:
> +    description: Reference to the GPIO connected to the reset pin. Active low.
> +    maxItems: 1
> +
> +  vdd-supply:
> +    description: Definition of the regulator used as 1.8V digital power supply.
> +
> +  port:
> +    $ref: /schemas/graph.yaml#/properties/port
> +    additionalProperties: false
> +
> +    properties:
> +      endpoint:
> +        $ref: /schemas/media/video-interfaces.yaml#
> +        unevaluatedProperties: false
> +
> +        properties:
> +          data-lanes:
> +            oneOf:
> +              - items:
> +                  - const: 1
> +                  - const: 2
> +                  - const: 3
> +                  - const: 4
> +              - items:
> +                  - const: 1
> +                  - const: 2
> +
> +        required:
> +          - data-lanes
> +
> +required:
> +  - compatible
> +  - reg
> +  - clocks
> +  - clock-names
> +  - rst-gpios
> +  - vdd-supply
> +  - port
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        hi846: camera@20 {
> +            compatible = "hynix,hi846";
> +            reg = <0x20>;
> +            clocks = <&clk>;
> +            clock-names = "mclk";
> +            vdd-supply = <&reg_camera_pwr_en>; /* 1.8v */
> +            rst-gpios = <&gpio1 25 GPIO_ACTIVE_LOW>;
> +
> +            port {
> +                camera_out: endpoint {
> +                    remote-endpoint = <&csi1_ep1>;
> +                    data-lanes = <1 2>;
> +                };
> +            };
> +        };
> +    };
> +
> +...
  

On Fri, May 28, 2021 at 11:35:35AM +0300, Laurent Pinchart wrote:
...
> > +    maxItems: 1
> > +
> > +  clocks:
> > +    description: Reference to the mclk clock.
> > +    maxItems: 1
> 
> You could also write this
> 
>   clocks:
>     items:
>       - description: Reference to the mclk clock.
> 
> The maxItems will then be implicit. This is the preferred form when
> multiple clocks are used, and given that clocks it meant to contain a
> list of clocks, even if it has a single entry, placing the description
> in a list of items may be a bit better semantically speaking.
> 
> > +
> > +  clock-names:
> > +    const: mclk
> 
> Similarly,
> 
>   clock-names:
>     items:
>       - const: mclk
> 
> Rob, is standardizing this pattern a good idea, or do you prefer the
> shorter form
> 
>   clock-names:
>     const: mclk

As there's just one clock, isn't the clock-names redundant?
  

On Wed, Jun 02, 2021 at 04:51:37PM +0300, Sakari Ailus wrote:
> Hi Martin,
> 
> On Fri, May 28, 2021 at 10:13:33AM +0200, Martin Kepplinger wrote:
> > Document the bindings used for the SK Hynix Hi-846 CMOS camera driver.
> > 
> > Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
> 
> Could you read Documentation/driver-api/media/camera-sensor.rst, please?
> 
> I believe you'll need assigned-clock-rates device property as well as

I dn't think assigned-clock-rates should be part of the bindings, it's a
mechanism that can be used in any DT device node.

> link-frequencies endpoint property.
> 
> > ---
> >  .../bindings/media/i2c/hynix,hi846.yaml       | 99 +++++++++++++++++++
> >  1 file changed, 99 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml b/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> > new file mode 100644
> > index 000000000000..2991108e23e5
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> > @@ -0,0 +1,99 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/media/i2c/hynix,hi846.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: SK Hynix Hi-846 1/4" 8M Pixel MIPI CSI-2 sensor
> > +
> > +maintainers:
> > +  - Martin Kepplinger <martin.kepplinger@puri.sm>
> > +
> > +description: |-
> > +  The Hi-846 is a raw image sensor with an MIPI CSI-2 image data
> > +  interface and CCI (I2C compatible) control bus. The output format
> > +  is 10bit Bayer.
> 
> Virtually all Bayer sensors can do 8 bpp, too. I'd drop the sentence

Not this one according to its datasheet (we can't rule out that this
would be possible an undocumented of course).

> mentoning 10 bits.
> 
> > +
> > +properties:
> > +  compatible:
> > +    const: hynix,hi846
> > +
> > +  reg:
> > +    description: I2C device address.
> > +    maxItems: 1
> > +
> > +  clocks:
> > +    description: Reference to the mclk clock.
> > +    maxItems: 1
> > +
> > +  clock-names:
> > +    const: mclk
> > +
> > +  rst-gpios:
> > +    description: Reference to the GPIO connected to the reset pin. Active low.
> > +    maxItems: 1
> > +
> > +  vdd-supply:
> > +    description: Definition of the regulator used as 1.8V digital power supply.
> > +
> > +  port:
> > +    $ref: /schemas/graph.yaml#/properties/port
> > +    additionalProperties: false
> > +
> > +    properties:
> > +      endpoint:
> > +        $ref: /schemas/media/video-interfaces.yaml#
> > +        unevaluatedProperties: false
> > +
> > +        properties:
> > +          data-lanes:
> > +            oneOf:
> > +              - items:
> > +                  - const: 1
> > +                  - const: 2
> > +                  - const: 3
> > +                  - const: 4
> > +              - items:
> > +                  - const: 1
> > +                  - const: 2
> > +
> > +        required:
> > +          - data-lanes
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - clocks
> > +  - clock-names
> > +  - rst-gpios
> > +  - vdd-supply
> > +  - port
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > +  - |
> > +    #include <dt-bindings/gpio/gpio.h>
> > +
> > +    i2c {
> > +        #address-cells = <1>;
> > +        #size-cells = <0>;
> > +
> > +        hi846: camera@20 {
> > +            compatible = "hynix,hi846";
> > +            reg = <0x20>;
> > +            clocks = <&clk>;
> > +            clock-names = "mclk";
> > +            vdd-supply = <&reg_camera_pwr_en>; /* 1.8v */
> > +            rst-gpios = <&gpio1 25 GPIO_ACTIVE_LOW>;
> > +
> > +            port {
> > +                camera_out: endpoint {
> > +                    remote-endpoint = <&csi1_ep1>;
> > +                    data-lanes = <1 2>;
> > +                };
> > +            };
> > +        };
> > +    };
> > +
> > +...
  

Am Mittwoch, dem 02.06.2021 um 17:05 +0300 schrieb Laurent Pinchart:
> On Wed, Jun 02, 2021 at 04:51:37PM +0300, Sakari Ailus wrote:
> > Hi Martin,
> > 
> > On Fri, May 28, 2021 at 10:13:33AM +0200, Martin Kepplinger wrote:
> > > Document the bindings used for the SK Hynix Hi-846 CMOS camera
> > > driver.
> > > 
> > > Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
> > 
> > Could you read Documentation/driver-api/media/camera-sensor.rst,
> > please?
> > 
> > I believe you'll need assigned-clock-rates device property as well
> > as
> 
> I dn't think assigned-clock-rates should be part of the bindings,
> it's a
> mechanism that can be used in any DT device node.
> 
> > link-frequencies endpoint property.
> > 
> > > ---
> > >  .../bindings/media/i2c/hynix,hi846.yaml       | 99
> > > +++++++++++++++++++
> > >  1 file changed, 99 insertions(+)
> > >  create mode 100644
> > > Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> > > 
> > > diff --git
> > > a/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> > > b/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> > > new file mode 100644
> > > index 000000000000..2991108e23e5
> > > --- /dev/null
> > > +++
> > > b/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> > > @@ -0,0 +1,99 @@
> > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > > +%YAML 1.2
> > > +---
> > > +$id: http://devicetree.org/schemas/media/i2c/hynix,hi846.yaml#
> > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > +
> > > +title: SK Hynix Hi-846 1/4" 8M Pixel MIPI CSI-2 sensor
> > > +
> > > +maintainers:
> > > +  - Martin Kepplinger <martin.kepplinger@puri.sm>
> > > +
> > > +description: |-
> > > +  The Hi-846 is a raw image sensor with an MIPI CSI-2 image data
> > > +  interface and CCI (I2C compatible) control bus. The output
> > > format
> > > +  is 10bit Bayer.
> > 
> > Virtually all Bayer sensors can do 8 bpp, too. I'd drop the
> > sentence
> 
> Not this one according to its datasheet (we can't rule out that this
> would be possible an undocumented of course).

actually there is one register that mentions raw8 output but I never
got that to work. I don't have to mention 10bit in this description.
thanks.

> 
> > mentoning 10 bits.
> > 
> > > +
> > > +properties:
> > > +  compatible:
> > > +    const: hynix,hi846
> > > +
> > > +  reg:
> > > +    description: I2C device address.
> > > +    maxItems: 1
> > > +
> > > +  clocks:
> > > +    description: Reference to the mclk clock.
> > > +    maxItems: 1
> > > +
> > > +  clock-names:
> > > +    const: mclk
> > > +
> > > +  rst-gpios:
> > > +    description: Reference to the GPIO connected to the reset
> > > pin. Active low.
> > > +    maxItems: 1
> > > +
> > > +  vdd-supply:
> > > +    description: Definition of the regulator used as 1.8V
> > > digital power supply.
> > > +
> > > +  port:
> > > +    $ref: /schemas/graph.yaml#/properties/port
> > > +    additionalProperties: false
> > > +
> > > +    properties:
> > > +      endpoint:
> > > +        $ref: /schemas/media/video-interfaces.yaml#
> > > +        unevaluatedProperties: false
> > > +
> > > +        properties:
> > > +          data-lanes:
> > > +            oneOf:
> > > +              - items:
> > > +                  - const: 1
> > > +                  - const: 2
> > > +                  - const: 3
> > > +                  - const: 4
> > > +              - items:
> > > +                  - const: 1
> > > +                  - const: 2
> > > +
> > > +        required:
> > > +          - data-lanes
> > > +
> > > +required:
> > > +  - compatible
> > > +  - reg
> > > +  - clocks
> > > +  - clock-names
> > > +  - rst-gpios
> > > +  - vdd-supply
> > > +  - port
> > > +
> > > +additionalProperties: false
> > > +
> > > +examples:
> > > +  - |
> > > +    #include <dt-bindings/gpio/gpio.h>
> > > +
> > > +    i2c {
> > > +        #address-cells = <1>;
> > > +        #size-cells = <0>;
> > > +
> > > +        hi846: camera@20 {
> > > +            compatible = "hynix,hi846";
> > > +            reg = <0x20>;
> > > +            clocks = <&clk>;
> > > +            clock-names = "mclk";
> > > +            vdd-supply = <&reg_camera_pwr_en>; /* 1.8v */
> > > +            rst-gpios = <&gpio1 25 GPIO_ACTIVE_LOW>;
> > > +
> > > +            port {
> > > +                camera_out: endpoint {
> > > +                    remote-endpoint = <&csi1_ep1>;
> > > +                    data-lanes = <1 2>;
> > > +                };
> > > +            };
> > > +        };
> > > +    };
> > > +
> > > +...
>
  

Hi Laurent,

On Wed, Jun 02, 2021 at 05:05:14PM +0300, Laurent Pinchart wrote:
> On Wed, Jun 02, 2021 at 04:51:37PM +0300, Sakari Ailus wrote:
> > Hi Martin,
> > 
> > On Fri, May 28, 2021 at 10:13:33AM +0200, Martin Kepplinger wrote:
> > > Document the bindings used for the SK Hynix Hi-846 CMOS camera driver.
> > > 
> > > Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
> > 
> > Could you read Documentation/driver-api/media/camera-sensor.rst, please?
> > 
> > I believe you'll need assigned-clock-rates device property as well as
> 
> I dn't think assigned-clock-rates should be part of the bindings, it's a
> mechanism that can be used in any DT device node.

What if it's required?

> 
> > link-frequencies endpoint property.
> > 
> > > ---
> > >  .../bindings/media/i2c/hynix,hi846.yaml       | 99 +++++++++++++++++++
> > >  1 file changed, 99 insertions(+)
> > >  create mode 100644 Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> > > 
> > > diff --git a/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml b/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> > > new file mode 100644
> > > index 000000000000..2991108e23e5
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/media/i2c/hynix,hi846.yaml
> > > @@ -0,0 +1,99 @@
> > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > > +%YAML 1.2
> > > +---
> > > +$id: http://devicetree.org/schemas/media/i2c/hynix,hi846.yaml#
> > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > +
> > > +title: SK Hynix Hi-846 1/4" 8M Pixel MIPI CSI-2 sensor
> > > +
> > > +maintainers:
> > > +  - Martin Kepplinger <martin.kepplinger@puri.sm>
> > > +
> > > +description: |-
> > > +  The Hi-846 is a raw image sensor with an MIPI CSI-2 image data
> > > +  interface and CCI (I2C compatible) control bus. The output format
> > > +  is 10bit Bayer.
> > 
> > Virtually all Bayer sensors can do 8 bpp, too. I'd drop the sentence
> 
> Not this one according to its datasheet (we can't rule out that this
> would be possible an undocumented of course).

Ok, fair enough.

> 
> > mentoning 10 bits.
> > 
> > > +
> > > +properties:
> > > +  compatible:
> > > +    const: hynix,hi846
> > > +
> > > +  reg:
> > > +    description: I2C device address.
> > > +    maxItems: 1
> > > +
> > > +  clocks:
> > > +    description: Reference to the mclk clock.
> > > +    maxItems: 1
> > > +
> > > +  clock-names:
> > > +    const: mclk
> > > +
> > > +  rst-gpios:
> > > +    description: Reference to the GPIO connected to the reset pin. Active low.
> > > +    maxItems: 1
> > > +
> > > +  vdd-supply:
> > > +    description: Definition of the regulator used as 1.8V digital power supply.
> > > +
> > > +  port:
> > > +    $ref: /schemas/graph.yaml#/properties/port
> > > +    additionalProperties: false
> > > +
> > > +    properties:
> > > +      endpoint:
> > > +        $ref: /schemas/media/video-interfaces.yaml#
> > > +        unevaluatedProperties: false
> > > +
> > > +        properties:
> > > +          data-lanes:
> > > +            oneOf:
> > > +              - items:
> > > +                  - const: 1
> > > +                  - const: 2
> > > +                  - const: 3
> > > +                  - const: 4
> > > +              - items:
> > > +                  - const: 1
> > > +                  - const: 2
> > > +
> > > +        required:
> > > +          - data-lanes
> > > +
> > > +required:
> > > +  - compatible
> > > +  - reg
> > > +  - clocks
> > > +  - clock-names
> > > +  - rst-gpios
> > > +  - vdd-supply
> > > +  - port
> > > +
> > > +additionalProperties: false
> > > +
> > > +examples:
> > > +  - |
> > > +    #include <dt-bindings/gpio/gpio.h>
> > > +
> > > +    i2c {
> > > +        #address-cells = <1>;
> > > +        #size-cells = <0>;
> > > +
> > > +        hi846: camera@20 {
> > > +            compatible = "hynix,hi846";
> > > +            reg = <0x20>;
> > > +            clocks = <&clk>;
> > > +            clock-names = "mclk";
> > > +            vdd-supply = <&reg_camera_pwr_en>; /* 1.8v */
> > > +            rst-gpios = <&gpio1 25 GPIO_ACTIVE_LOW>;
> > > +
> > > +            port {
> > > +                camera_out: endpoint {
> > > +                    remote-endpoint = <&csi1_ep1>;
> > > +                    data-lanes = <1 2>;
> > > +                };
> > > +            };
> > > +        };
> > > +    };
> > > +
> > > +...
> 
> -- 
> Regards,
> 
> Laurent Pinchart