Re: [PATCH 0/5] drm/vkms: support more formats and fix RGB565 regression

[Sidharth Saha <ssaha2000@gmail.com>]

Hi Matheus,

Following up on my earlier report: I've now written KUnit tests for
the conversions in this series - argb_u16_to_RGB565(),
argb_u16_to_BGR565(), the RGB565/BGR565 read paths, and both the read
and write paths for RGB332 and BGR233 - against hand-computed values:
zero, max, single channels, the midpoint, values either side of each
rounding step, distinct per-channel values, and a read/write round
trip.

All pass with the series applied. Without it, the RGB565 writeback
midpoint and rounding-step cases fail (truncated instead of rounded),
and the RGB565/BGR565 read tests give identical results with and
without the series, so the helper conversion in 3/5 doesn't change
behavior.

For the series:

Tested-by: Sidharth Saha ssaha2000@gmail.com

I'm happy to send the tests as a follow-up series once this lands, or
you're welcome to fold them into a v2.

Thanks,
Sidharth

On 9/27/2026 5:52 PM, Matheus Alves de Almeida wrote:
> Hi,
> 
> This series adds support for RGB332, BGR233 and BGR565 writeback. This
> is done with new helpers added to make conversion easier. It also fixes
> a regression in the RGB565 write conversion.