SC20 - Adding new panel

Hi folks,

I am trying to add a support for a new panel to my SC20-AU. The panel model is CH430WV10 and the driver model is ST7701S. According to “SC20 Cameras and LCDs.pdf” document, this drivers is not supported by default.
I follow the “QUECTEL_SC20_Display_Driver_Development_Guide.pdf” and could add the new panel to the DTS and LK with data provided for the panel vendor. After booting I get this from system information:

root@msm8909:~# cat /sys/class/graphics/fb0/msm_fb_panel_info 
pu_en=0
xstart=0
walign=0
ystart=0
halign=0
min_w=0
min_h=0
roi_merge=0
dyn_fps_en=0
min_fps=0
max_fps=0
panel_name=st7701s 480p video mode dsi panel
primary_panel=1
is_pluggable=0
display_id=
is_cec_supported=0
is_pingpong_split=0
is_hdr_enabled=0
peak_brightness=0
blackness_level=0
white_chromaticity_x=0
white_chromaticity_y=0
red_chromaticity_x=0
red_chromaticity_y=0
green_chromaticity_x=0
green_chromaticity_y=0
blue_chromaticity_x=0
blue_chromaticity_y=0

root@msm8909:~# cat /sys/class/graphics/fb0/msm_fb_panel_status
panel_status=alive

But the screen doesn’t show any image. If I execute some graphic application I read the next:

root@msm8909:~# /tmp/pruebaLcdman 
I/Adreno-EGL (6448,6448): <qeglDrvAPI_eglInitialize:379>: EGL 1.4 QUALCOMM build:  ()
OpenGL ES Shader Compiler Version: E031.36.04.03
Build Date: 12/17/18 Mon
Local Branch: 
Remote Branch: 
Local Patches: 
Reconstruct Branch: 
E/Adreno-EGLSUB (6448,6448): <eglSubDriverMain:2093>: @ () -> TRUE
E/Adreno-EGLSUB (6448,6448): <Initialize:520>: Android SubDriver

I tried configuring different framerates, using only 1 dsi lane, different timings values, but nothing, not even one single line on the display.
Something is missing or need to be configured.

I share with you the files generated for my panel:
panel_files.zip (3.9 KB)

Can somebody give me a hand??

Thanks in advance.

Hi Rovogel:
Are you debugging this LCD on Yocto Linux or Android?

Hi @robertlong-Q,

The above logs are from Yocto Linux. But I porting this LCD to Android too with the same result.

Pls show us the UART log , when booting, and if possible pls give us the datasheet and spec of your LCD

Hello Rovogel,
I’m also looking to interface ST7701S based display with SC20.
Did you get success in yours?

Best regards,
Keshav Aggarwal