Re: [PATCH v2 2/3] Input: aw86938 - add driver for Awinic AW86938

["Luca Weiss" <luca.weiss@fairphone.com>]

Hi Konrad,

On Mon Feb 2, 2026 at 11:12 AM CET, Konrad Dybcio wrote:
> On 2/1/26 2:49 AM, Dmitry Torokhov wrote:
>> Hi Griffin,
>> 
>> On Wed, Jan 28, 2026 at 04:51:14PM +0100, Griffin Kroah-Hartman wrote:
>>> @@ -717,9 +746,19 @@ static int aw86927_detect(struct aw86927_data *haptics)
>>>  
>>>  	chip_id = be16_to_cpu(read_buf);
>>>  
>>> -	if (chip_id != AW86927_CHIPID) {
>>> -		dev_err(haptics->dev, "Unexpected CHIPID value 0x%x\n", chip_id);
>>> -		return -ENODEV;
>>> +	switch (haptics->model) {
>>> +	case AW86927:
>>> +		if (chip_id != AW86927_CHIPID) {
>>> +			dev_err(haptics->dev, "Unexpected CHIPID value 0x%x\n", chip_id);
>>> +			return -ENODEV;
>>> +		}
>> 
>> If we are able to query chip ID why do we need to have separate
>> compatibles? I would define chip data structure with differences between
>> variants and assign and use it instead of having separate compatible.
>
> dt-bindings guidelines explicitly call for this, a chipid comparison
> then works as a safety net

Are you saying, that

1. we should enforce dt-bindings == CHIP_ID (what's currently done)

or

2. we should have both compatibles with no handling based on compatible,
   but only use CHIP_ID at runtime to change behavior

Regards
Luca