Re: [PATCH v10 43/55] dt-bindings: input: atmel: support to set max bytes transferred

From: Dmitry Osipenko
Date: Wed Apr 01 2020 - 10:39:03 EST


31.03.2020 13:50, Jiada Wang ÐÐÑÐÑ:
> Add support to set max bytes transferred in an i2c transaction
>
> Signed-off-by: Jiada Wang <jiada_wang@xxxxxxxxxx>
> ---
> Documentation/devicetree/bindings/input/atmel,maxtouch.txt | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
> index 126266891cdc..37a798cab0dd 100644
> --- a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
> +++ b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
> @@ -45,6 +45,8 @@ Optional properties for main touchpad device:
>
> - atmel,input_name: Override name of input device from the default.
>
> +- atmel,mtu: Maximum number of bytes that can read/transferred in an i2c transaction
> +
> Example:
>
> touch@4b {
> @@ -52,4 +54,5 @@ Example:
> reg = <0x4b>;
> interrupt-parent = <&gpio>;
> interrupts = <TEGRA_GPIO(W, 3) IRQ_TYPE_LEVEL_LOW>;
> + atmel,mtu = <200>
> };
>

Is this a software (firmware) limitation which varies from version to
version?

If the limitation is per-hardware version, then perhaps should be better
to have a hardcoded per-hardware table of limits in the driver?