Re: [PATCH] dt-bindings: media: i2c: Fix external clock frequency for OV5645

From: Sakari Ailus
Date: Wed Nov 14 2018 - 05:57:16 EST


Hi Manivannan,

On Wed, Nov 14, 2018 at 04:09:35PM +0530, Manivannan Sadhasivam wrote:
> Commit "4adb0a0432f4 media: ov5645: Supported external clock is 24MHz"
> modified the external clock frequency to be 24MHz instead of the
> 23.88MHz in driver. Hence, make the same change in corresponding bindings
> doc and mention the acceptable tolerance.
>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> ---
> Documentation/devicetree/bindings/media/i2c/ov5645.txt | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/media/i2c/ov5645.txt b/Documentation/devicetree/bindings/media/i2c/ov5645.txt
> index fd7aec9f8e24..b155583469a4 100644
> --- a/Documentation/devicetree/bindings/media/i2c/ov5645.txt
> +++ b/Documentation/devicetree/bindings/media/i2c/ov5645.txt
> @@ -8,7 +8,8 @@ Required Properties:
> - compatible: Value should be "ovti,ov5645".
> - clocks: Reference to the xclk clock.
> - clock-names: Should be "xclk".
> -- clock-frequency: Frequency of the xclk clock.
> +- clock-frequency: Frequency of the xclk clock. Should be 24MHz with 1%
> + acceptable tolerance.

DT bindings are for documenting the hardware, not the driver implementation.
The sensor supports a range AFAIU, not a specific frequency.

The bit below seems good.

> - enable-gpios: Chip enable GPIO. Polarity is GPIO_ACTIVE_HIGH. This corresponds
> to the hardware pin PWDNB which is physically active low.
> - reset-gpios: Chip reset GPIO. Polarity is GPIO_ACTIVE_LOW. This corresponds to
> @@ -37,7 +38,7 @@ Example:
>
> clocks = <&clks 200>;
> clock-names = "xclk";
> - clock-frequency = <23880000>;
> + clock-frequency = <24000000>;
>
> vdddo-supply = <&camera_dovdd_1v8>;
> vdda-supply = <&camera_avdd_2v8>;
> --
> 2.17.1
>

--
Sakari Ailus
e-mail: sakari.ailus@xxxxxx