[PATCH 1/2] drm/vc4: hdmi: Disable Wifi Frequencies

[Rob Herring]

On Fri, Sep 25, 2020 at 03:07:43PM +0200, Maxime Ripard wrote:
> There's cross-talk on the RPi4 between the 2.4GHz channels used by the WiFi
> chip and some resolutions, most notably 1440p at 60Hz.
> 
> In such a case, we can either reject entirely the mode, or lower slightly
> the pixel frequency to remove the overlap. Let's go for the latter.
> 
> Signed-off-by: Maxime Ripard <maxime at cerno.tech>
> ---
>  .../bindings/display/brcm,bcm2711-hdmi.yaml        |  6 ++++++
>  drivers/gpu/drm/vc4/vc4_hdmi.c                     | 14 +++++++++++++-
>  drivers/gpu/drm/vc4/vc4_hdmi.h                     |  8 ++++++++
>  3 files changed, 27 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/display/brcm,bcm2711-hdmi.yaml b/Documentation/devicetree/bindings/display/brcm,bcm2711-hdmi.yaml
> index 03a76729d26c..63e7fe999c0a 100644
> --- a/Documentation/devicetree/bindings/display/brcm,bcm2711-hdmi.yaml
> +++ b/Documentation/devicetree/bindings/display/brcm,bcm2711-hdmi.yaml
> @@ -76,6 +76,12 @@ properties:
>    resets:
>      maxItems: 1
>  
> +  raspberrypi,disable-wifi-frequencies:
> +    type: boolean
> +    description: >
> +      Should the pixel frequencies in the WiFi frequencies range be
> +      avoided?

Based on googling the issue, perhaps should be a common property?