[RFC PATCH 0/2] drm/mediatek/hdmi : split legacy driver and add mt8195

[Guillaume Ranquet]

Following the review of "[v1,4/4] drm/mediatek: add mt8195 hdmi TX support" [1] , I've been asked to try to merge the "legacy
HDMI driver with the "new" mt8195 HDMI driver. Though the registers and IPs are rather different, I've made an attempt at the
excercise on which I would like some comments before submitting a new version of the patchset.

I've created a new mtk_hdmi_common.{c,h} which contains what I could identify as common enough to be added in there.
I have not renamed the mtk_hdmi.{c,h} driver to something else yet.
I've then added mtk8195 hdmi driver on top of this work.

The code is still rather sketchy and I have some questions on best practices for that kind of exercices?
In no particular order, here's a bunch of random questions:

1 would you rather have:
- as presented here: a boolean with a bunch of if/else in the common code to handle the discrepencies between the two drivers
- function pointers, with an "ops" structure set in the drvdata... though the ops are a bit random and wouldn't really
make sense to be grouped together?

2 I'm not really happy with how the mt8195 driver and ddc are sharing the same __iomem regs and not sure how to exactly
handle this now that both hdmi drivers are tied together... it was hackish from the begining, but now I'm a bit out of
solutions to handle this peculiar "feature" of the mt8195 hdmi/ddc driver. any hints would be appreciated.

3 Should the "legacy" and mt8195 drivers be under the same menu entry?

4 I'm looking into the clock framework and I'm wondering if there would be benefits to switch to the "bulk" interface? as
both driver seem to request them all once and for all? the code might end up easier to read.

5 Would it be beneficial to further split the driver with audio on one side and video on the other? from what I understood,
the main complaint was that the driver was too big to review... that could help with that at least?


Thx for your patience... any further comment is welcome.

Thx,
Guillaume.

[1] https://patchwork.kernel.org/project/linux-mediatek/patch/20210929094425.745-5-granquet@baylibre.com/

-- 
Guillaume Ranquet (2):
  drm/mediatek: extract common functions from the mtk hdmi driver
  drm/mediatek: add mtk8195 hdmi display driver

 drivers/gpu/drm/mediatek/Kconfig              |   10 +
 drivers/gpu/drm/mediatek/Makefile             |    5 +-
 drivers/gpu/drm/mediatek/mtk_hdmi.c           |  635 +-----
 drivers/gpu/drm/mediatek/mtk_hdmi_common.c    |  521 +++++
 drivers/gpu/drm/mediatek/mtk_hdmi_common.h    |  258 +++
 drivers/gpu/drm/mediatek/mtk_mt8195_hdmi.c    | 1835 +++++++++++++++++
 drivers/gpu/drm/mediatek/mtk_mt8195_hdmi.h    |   26 +
 .../gpu/drm/mediatek/mtk_mt8195_hdmi_ddc.c    |  530 +++++
 .../gpu/drm/mediatek/mtk_mt8195_hdmi_ddc.h    |   20 +
 .../gpu/drm/mediatek/mtk_mt8195_hdmi_regs.h   |  329 +++
 10 files changed, 3560 insertions(+), 609 deletions(-)
 create mode 100644 drivers/gpu/drm/mediatek/mtk_hdmi_common.c
 create mode 100644 drivers/gpu/drm/mediatek/mtk_hdmi_common.h
 create mode 100644 drivers/gpu/drm/mediatek/mtk_mt8195_hdmi.c
 create mode 100644 drivers/gpu/drm/mediatek/mtk_mt8195_hdmi.h
 create mode 100644 drivers/gpu/drm/mediatek/mtk_mt8195_hdmi_ddc.c
 create mode 100644 drivers/gpu/drm/mediatek/mtk_mt8195_hdmi_ddc.h
 create mode 100644 drivers/gpu/drm/mediatek/mtk_mt8195_hdmi_regs.h

-- 
2.32.0