Re: [PATCH 12/12] Input: docs: add more details on the use of BTN_TOOL

[Peter Hutterer <peter.hutterer@who-t.net>]

On Wed, Jan 26, 2022 at 05:18:32PM +0100, Benjamin Tissoires wrote:
> The HID core stack used to be very relaxed considering the BTN_TOOL_*
> usage. With the recent commits, we should now enforce to have only one
> tool at a time, meaning that we can now express that requirement in the
> docs.
> 
> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
> ---
>  Documentation/input/event-codes.rst | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/input/event-codes.rst b/Documentation/input/event-codes.rst
> index b24ae7d292cc..41b1fa647dab 100644
> --- a/Documentation/input/event-codes.rst
> +++ b/Documentation/input/event-codes.rst
> @@ -137,7 +137,10 @@ A few EV_KEY codes have special meanings:
>      code should be set to a value of 1. When the tool is no longer interacting
>      with the input device, the BTN_TOOL_<name> code should be reset to 0. All
>      trackpads, tablets, and touchscreens should use at least one BTN_TOOL_<name>
> -    code when events are generated.
> +    code when events are generated. Likewise all trackpads, tablets, and
> +    touchscreens should export only one BTN_TOOL_<name> at a time. It is

s/export/set to nonzero/ to avoid any ambiguity with setting the evbit on the
device vs setting the value to nonzero.

> +    however accepted to switch tool in one EV_SYN frame by setting the old
> +    BTN_TOOL_<name> at a value of 0 and the new one at 1.

I would even s/accepted/recommended/ but this LGTM to me, thanks.

Acked-by: Peter Hutterer <peter.hutterer@who-t.net>

Cheers,
  Peter