Re: [PATCH v3 0/9] drm/mipi-dsi: Reduce bloat and add funcs for cleaner init seqs

[Neil Armstrong <neil.armstrong@linaro.org>]

Hi,

On 01/05/2024 17:41, Douglas Anderson wrote:
> The consensus of many DRM folks is that we want to move away from DSI
> drivers defining tables of init commands. Instead, we want to move to
> init functions that can use common DRM functions. The issue thus far
> has been that using the macros mipi_dsi_generic_write_seq() and
> mipi_dsi_dcs_write_seq() bloats the driver using them.
> 
> While trying to solve bloat, we realized that the majority of the it
> was easy to solve. This series solves the bloat for existing drivers
> by moving the printout outside of the macro.
> 
> During discussion of my v1 patch to fix the bloat [1], we also decided
> that we really want to change the way that drivers deal with init
> sequences to make it clearer. In addition to being cleaner, a side
> effect of moving drivers to the new style reduces bloat _even more_.
> 
> This series also contains a few minor fixes / cleanups that I found
> along the way.
> 
> This series converts four drivers over to the new
> mipi_dsi_dcs_write_seq_multi() function. Not all conversions have been
> tested, but hopefully they are straightforward enough. I'd appreciate
> testing.
> 
> NOTE: In v3 I tried to incorporate the feedback from v2. I also
> converted the other two panels I could find that used table-based
> initialization.
> 
> [1] https://lore.kernel.org/r/20240424172017.1.Id15fae80582bc74a0d4f1338987fa375738f45b9@changeid
> 
> Changes in v3:
> - ("mipi_dsi_*_write functions don't need to ratelimit...") moved earlier.
> - Add a TODO item for cleaning up the deprecated macros/functions.
> - Fix spacing of init function.
> - Inline kerneldoc comments for struct mipi_dsi_multi_context.
> - Rebased upon patch to remove ratelimit of prints.
> - Remove an unneeded error print.
> - Squash boe-tv101wum-nl6 lowercase patch into main patch
> - Use %zd in print instead of casting errors to int.
> - drm/panel: ili9882t: Don't use a table for initting panels
> - drm/panel: innolux-p079zca: Don't use a table for initting panels
> 
> Changes in v2:
> - Add some comments to the macros about printing and returning.
> - Change the way err value is handled in prep for next patch.
> - Modify commit message now that this is part of a series.
> - Rebased upon patches to avoid theoretical int overflow.
> - drm/mipi-dsi: Fix theoretical int overflow in mipi_dsi_dcs_write_seq()
> - drm/mipi-dsi: Fix theoretical int overflow in mipi_dsi_generic_write_seq()
> - drm/mipi-dsi: Introduce mipi_dsi_*_write_seq_multi()
> - drm/mipi-dsi: mipi_dsi_*_write functions don't need to ratelimit prints
> - drm/panel: boe-tv101wum-nl6: Convert hex to lowercase
> - drm/panel: boe-tv101wum-nl6: Don't use a table for initting commands
> - drm/panel: novatek-nt36672e: Switch to mipi_dsi_dcs_write_seq_multi()
> 
> Douglas Anderson (9):
>    drm/mipi-dsi: Fix theoretical int overflow in mipi_dsi_dcs_write_seq()
>    drm/mipi-dsi: Fix theoretical int overflow in
>      mipi_dsi_generic_write_seq()
>    drm/mipi-dsi: mipi_dsi_*_write functions don't need to ratelimit
>      prints
>    drm/mipi-dsi: Reduce driver bloat of mipi_dsi_*_write_seq()
>    drm/mipi-dsi: Introduce mipi_dsi_*_write_seq_multi()
>    drm/panel: novatek-nt36672e: Switch to mipi_dsi_dcs_write_seq_multi()
>    drm/panel: boe-tv101wum-nl6: Don't use a table for initting panels
>    drm/panel: ili9882t: Don't use a table for initting panels
>    drm/panel: innolux-p079zca: Don't use a table for initting panels

Thanks Doug!

I think we all agree on the core changes, now I think we can wait a few weeks
and try to get some test feedbacks on the indirectly and directly affected
panels, drm-misc-next won't be merged into linux-next until v6.10-rc1 anyway
so we have some time to test on our boards.

Neil
> 
>   Documentation/gpu/todo.rst                    |   18 +
>   drivers/gpu/drm/drm_mipi_dsi.c                |  112 +
>   .../gpu/drm/panel/panel-boe-tv101wum-nl6.c    | 2792 +++++++++--------
>   drivers/gpu/drm/panel/panel-ilitek-ili9882t.c |  794 +++--
>   drivers/gpu/drm/panel/panel-innolux-p079zca.c |  284 +-
>   .../gpu/drm/panel/panel-novatek-nt36672e.c    |  576 ++--
>   include/drm/drm_mipi_dsi.h                    |  101 +-
>   7 files changed, 2451 insertions(+), 2226 deletions(-)
>