| Message ID | 20240506-tc358775-fix-powerup-v1-0-545dcf00b8dd@kernel.org (mailing list archive) |
|---|---|
| Headers | show |
| Series | drm/bridge: tc358775: proper bridge bringup and code cleanup | expand |
On Mon May 6, 2024 at 3:34 PM CEST, Michael Walle wrote: > 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.baryshkov@linaro.org/ Any comments on this series, besides the discussion on how to do the reset during LP11? Most of the other patches should be more or less self contained. -michael
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.baryshkov@linaro.org/ Signed-off-by: Michael Walle <mwalle@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