This patchset fixes the bridge initialization according to the
datasheet. Not sure how that even worked before. Maybe because the
initialization was done prior to linux (?).
The bridge has some peculiarities:
(1) The reset has to be deasserted in LP-11 mode
(2) For I2C access the bridge needs the DSI clock
(3) The bridge has to be configured while the video stream is
disabled.
(4) The bridge has limitations on the display timings. In particular,
the horizontal pulse width has to be at least 8 pixels wide and
both the horizontal pulse width as well as the back porch has to
be even. According to the datasheet the horizontal front porch as
well but in line sync mode, this is ignored. Also line sync is the
only supported mode for this bridge, therefore, the front porch
is always ignored.
The most controversial patch is probably "drm/bridge: add
dsi_lp11_notify mechanism" which is needed for (1) above. Some time ago
there was a series [1] to add a manual power-up, which was abandoned and
which didn't suite the needs for this bridge anyway.
Also, this will gradually change the tc_ prefix to tc358775_ while the
functions are refactored.
The bridge was successfully tested on a Mediatek MT8195 SoC with the
following panels:
- Innolux G101ICE
- AUO G121EAN01.0
- Innolux G156HCE (dual-link LVDS)
[1]
https://lore.kernel.org/r/20231016165355.1327217-1-dmitry.barysh...@linaro.org/
Signed-off-by: Michael Walle <mwa...@kernel.org>
---
Michael Walle (20):
drm/bridge: add dsi_lp11_notify mechanism
drm/mediatek: dsi: provide LP-11 mode during .pre_enable
drm/mediatek: dsi: add support for .dsi_lp11_notity()
drm/bridge: tc358775: fix regulator supply id
drm/bridge: tc358775: add crtc modes fixup
drm/bridge: tc358775: redefine LV_MX()
drm/bridge: tc358775: use regmap instead of open coded access functions
drm/bridge: tc358775: remove error message if regulator is missing
drm/bridge: tc358775: remove complex vsdelay calculation
drm/bridge: tc358775: simplify lvds_link property
drm/bridge: tc358775: reformat weird indentation
drm/bridge: tc358775: correctly configure LVDS clock
drm/bridge: tc358775: split the init code
drm/bridge: tc358775: configure PLL depending on the LVDS clock
drm/bridge: tc358775: dynamically configure DSI link settings
drm/bridge: tc358775: use proper defines to configure LVDS timings
drm/bridge: tc358775: move bridge power up/down into functions
drm/bridge: tc358775: fix the power-up/down delays
drm/bridge: tc358775: fix power-up sequencing
drm/bridge: tc358775: use devm_drm_bridge_add()
drivers/gpu/drm/bridge/Kconfig | 1 +
drivers/gpu/drm/bridge/tc358775.c | 601 ++++++++++++++++++++-----------------
drivers/gpu/drm/drm_bridge.c | 16 +
drivers/gpu/drm/mediatek/mtk_dsi.c | 8 +-
include/drm/drm_bridge.h | 12 +
5 files changed, 355 insertions(+), 283 deletions(-)
---
base-commit: 9221b2819b8a4196eecf5476d66201be60fbcf29
change-id: 20240506-tc358775-fix-powerup-53f490043179
