drm/panel: boe-tv101wum-nl6: Fine tune Himax83102-j02 panel HFP and HBP
authorCong Yang <yangcong5@huaqin.corp-partner.google.com>
Mon, 20 Nov 2023 02:01:09 +0000 (10:01 +0800)
committerDouglas Anderson <dianders@chromium.org>
Tue, 21 Nov 2023 18:12:34 +0000 (10:12 -0800)
commitcea7008190ad65b4aaae6e94667a358d2c10a696
treec74a2097a3912243cc71673f80623ab0d35b3e02
parent8d6ef26501b97243ee6c16b8187c5b38cb69b77d
drm/panel: boe-tv101wum-nl6: Fine tune Himax83102-j02 panel HFP and HBP

The refresh reported by modetest is 60.46Hz, and the actual measurement
is 60.01Hz, which is outside the expected tolerance. Adjust hporch and
pixel clock to fix it. After repair, modetest and actual measurement were
all 60.01Hz.

Modetest refresh = Pixel CLK/ htotal* vtotal, but measurement frame rate
is HS->LP cycle time(Vblanking). Measured frame rate is not only affecte
by Htotal/Vtotal/pixel clock, also affected by Lane-num/PixelBit/LineTime
/DSI CLK. Assume that the DSI controller could not make the mode that we
requested(presumably it's PLL couldn't generate the exact pixel clock?).
If you use a different DSI controller, you may need to readjust these
parameters. Now this panel looks like it's only used by me on the MTK
platform, so let's change this set of parameters.

Fixes: 1bc2ef065f13 ("drm/panel: Support for Starry-himax83102-j02 TDDI MIPI-DSI panel")
Signed-off-by: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231120020109.3216343-1-yangcong5@huaqin.corp-partner.google.com
drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c