Re: [PATCH] input/touchscreen: synaptics_tcm_oncell: add driver

From: friederhannenheim
Date: Sat Mar 30 2024 - 16:36:02 EST


On 2024-03-28 18:53, Dmitry Torokhov wrote:
> [ now CCing for real ]
>
> Hi Frieder,
>
> On Wed, Mar 27, 2024 at 10:39:12PM +0100, Frieder Hannenheim wrote:
>> This is a bit of a stripped down and partially reworked driver for the
>> synaptics_tcm_oncell touchscreen. I based my work off the driver in the
>> LineageOS kernel found at
>> https://github.com/LineageOS/android_kernel_oneplus_sm8250 branch
>> lineage-20. The code was originally written by OnePlus developers but
>> I'm not sure how to credit them correctly.
>
> So the first question is: does this device not use Synaptics RMI4
> protocol?
>
> I am CCing Marge Yang of Synaptics who may shed some light on the kind
> of touch controller this is.
>
> Thanks.
Hi Dmitri,

the synaptics-s3908 uses a command based protocol whereas rmi4 is
register-based (as far as I understand it, I haven't been able to read
up on it properly since information on the internet is sparse). So I'm
pretty sure that it can not be controlled via rmi4.

Best wishes,
Frieder