Re: [PATCH v4 2/3] dt-bindings: sc16is7xx: Add compatible line for XR20M1172 UART

From: Krzysztof Kozlowski
Date: Fri Apr 19 2024 - 10:24:27 EST


On 19/04/2024 16:17, Konstantin P. wrote:
> On Fri, Apr 19, 2024 at 5:08 PM Conor Dooley <conor@xxxxxxxxxx> wrote:
>>
>> On Fri, Apr 19, 2024 at 03:45:02PM +0300, Konstantin Pugin wrote:
>>> From: Konstantin Pugin <ria.freelander@xxxxxxxxx>
>>>
>>> Add EXAR XR20M1172 UART compatible line into devicetree documentation.
>>
>> What you're doing is obvious from the diff, why this exar device is
>> related to the nxp devices is what should be mentioned here.
>>
>> Thanks,
>> Conor.
>
> It is already mentioned in cover letter and in previous patches in the
> series. Do I need to repeat it in DTS patch?
> If so, I will do it.
>
> Citation from my cover letter:
>
> EXAR XR20M1172 UART is mostly SC16IS762-compatible, but
> it has additional register which can change UART multiplier
> to 4x and 8x, similar to UPF_MAGIC_MULTIPLIER does. So, I used this
> flag to guard access to its specific DLD register. It seems than
> other EXAR SPI UART modules also have this register, but I tested
> only XR20M1172.
> Yes, in datasheet this register is called "DLD - Divisor Fractional"
> or "DLD - Divisor Fractional Register", calling depends on datasheet
> version.

Commits must stand on their own. Cover letter is not merged. This is the
place where you add new hardware, so here you describe and explain the
hardware.

Best regards,
Krzysztof