Re: [PATCH v2 1/3] dt-bindings: HID: i2c-hid: Label this binding as deprecated

[Rob Herring]

On Fri, Oct 23, 2020 at 04:22:52PM -0700, Douglas Anderson wrote:
> As pointed out by Rob Herring [1], we should have a device-specific
> compatible string.  This means people shouldn't be using the
> "i2c-over-hid" compatible string anymore, or at least not without a
> more specific compatible string before it.  Specifically:
> 
> 1. For newly added devices we should just have the device-specific
>    device string (no "hid-over-i2c" fallback) and infer the timings
>    and hid-descr-addr from there.

I wouldn't go that far. Having a fallback is perfectly acceptible. And 
hopefully there are at least some devices where that's good enough for 
drivers to use.

If we have cases of only 'i2c-over-hid' being used (in DT), then the 
solution is making this a schema so we can enforce that as not valid.

> 
> 2. If there's a need for a device tree to be backward compatible, we
>    should list the device-specific compatible string and add the
>    "hid-over-i2c" fallback and the various timings.
> 
> [1] https://lore.kernel.org/r/20201019211036.GA3595039@bogus
> 
> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> ---
> 
> Changes in v2:
> - ("dt-bindings: HID: i2c-hid: Label this binding as deprecated") new in v2.
> 
>  Documentation/devicetree/bindings/input/hid-over-i2c.txt | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/input/hid-over-i2c.txt b/Documentation/devicetree/bindings/input/hid-over-i2c.txt
> index c76bafaf98d2..733a5f053280 100644
> --- a/Documentation/devicetree/bindings/input/hid-over-i2c.txt
> +++ b/Documentation/devicetree/bindings/input/hid-over-i2c.txt
> @@ -1,5 +1,8 @@
>  * HID over I2C Device-Tree bindings
>  
> +WARNING: this binding is deprecated.  Instead of using this, create specific
> +bindings for each hid-over-i2c device.
> +
>  HID over I2C provides support for various Human Interface Devices over the
>  I2C bus. These devices can be for example touchpads, keyboards, touch screens
>  or sensors.
> -- 
> 2.29.0.rc1.297.gfa9743e501-goog
>