Re: [RFC PATCH 2/9] drm: bridge: Add Samsung SEC MIPI DSIM bridge driver

From: Frieder Schrempf
Date: Mon Jun 28 2021 - 04:19:59 EST


Hi Jagan,

On 24.06.21 10:30, Krzysztof Kozlowski wrote:
> On 24/06/2021 04:48, Fabio Estevam wrote:
>> Hi Jagan/Laurent,
>>
>> On Wed, Jun 23, 2021 at 7:23 PM Laurent Pinchart
>> <laurent.pinchart@xxxxxxxxxxxxxxxx> wrote:
>>
>>> Looking at the register set, it seems to match the Exynos 5433,
>>> supported by drivers/gpu/drm/exynos/exynos_drm_dsi.c. Can we leverage
>>> that driver instead of adding a new one for the same IP core ?
>>
>> Yes. there was an attempt from Michael in this direction:
>> https://eur04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatchwork.kernel.org%2Fproject%2Fdri-devel%2Fcover%2F20200911135413.3654800-1-m.tretter%40pengutronix.de%2F&amp;data=04%7C01%7Cfrieder.schrempf%40kontron.de%7C52db05459ef0462d5a9b08d936eab1ba%7C8c9d3c973fd941c8a2b1646f3942daf1%7C0%7C0%7C637601203901391193%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=LTYk9kpUeB9bgfRITQT6wIij3XTOIk37AHXbzQ2UI4Y%3D&amp;reserved=0
>
> That's the proper direction (maybe as Marek suggested - sharing common
> code like for Analogix DP), not duplicating a driver.
>

Just to make sure that you are aware of the previous patches and discussions here are some additional pointers:

* i.MX8MM glue code from Marek (+ Cc): [1]
* DPHY driver from Marek: [2]
* General discussion about driver implementation: [3]
* Daniel's (+ Cc) suggested direction to move forward: [4]

It looks like you already did a fork of the Exynos driver, so your approach might be generally in line with what Daniel suggested.

Best regards
Frieder

[1] https://patchwork.kernel.org/project/linux-arm-kernel/patch/20201005134250.527153-3-marex@xxxxxxx/
[2] https://patchwork.kernel.org/project/linux-arm-kernel/patch/20201003225020.164358-1-marex@xxxxxxx/
[3] https://patchwork.kernel.org/project/dri-devel/patch/20200911135413.3654800-11-m.tretter@xxxxxxxxxxxxxx/
[4] https://patchwork.kernel.org/project/dri-devel/patch/20200911135413.3654800-11-m.tretter@xxxxxxxxxxxxxx/#23995147