iMX6Q SABRE-AI Android M6 LVDS Backlight going off while bootup

kirangv — Wed, 29 Mar 2017 07:09:18 GMT

Hello,

I am working with i.MX 6Quad SABRE-AI board and I tried to flash board image and boot from SD card.

I have followed "android_M6.0.1_2.1.0_docs/Android_Quick_Start_Guide" section 4.3.

I have successfully flashed and booted from SD card , while booting i can see splash screen from u-boot and kernel logo (tux) on the LVDS screen , but suddenly the backlight of LVDS goes off (once the kernel starts).

We have found out that enable pin to LVDS is HIGH during the bootup (backlight ON) and it becomes LOW (backlight OFF) once the kernel starts.

Note : We can see the contents on the LVDS screen (if we look from an angle ) , so we believe if backlight is enabled LVDS would work proper for us.

Bootup snippet :

--------------------------------------------------------------------------------------

pwm-backlight supply power not found, using dummy regulator
MIPI DSI driver module loaded
MIPI DSI driver module loaded
mxc_sdc_fb fb@0: registered mxc display driver ldb
imx-ipuv3 2800000.ipu: IPU DMFC DP HIGH RESOLUTION: 1(0,1), 5B(2~5), 5F(6,7)
Console: switching to colour frame buffer device 128x48

--------------------------------------------------------------------------------------

Please find the full boot up log attached.

android_m6.0.1_1.0.0

Thanks,

Kiran

Original Attachment has been moved to: bootup_log.txt.zip

Re: iMX6Q SABRE-AI Android M6 LVDS Backlight going off while bootup

kirangv — Wed, 05 Apr 2017 06:33:49 GMT

Issue fixed , backlight it working now.

We had to enable "cabc-enable" for "lvds0" inside "hannstar_cabc" in 'imx6qdl-sabreauto.dtsi".

Got help from following Link :

https://community.nxp.com/thread/441817

Re: iMX6Q SABRE-AI Android M6 LVDS Backlight going off while bootup

Rita_Wang — Mon, 17 Apr 2017 07:24:23 GMT

Hi Kiran,

Many thanks for sharing it with everyone.

Have a nice day

Rita

i.MX ProcessorsのトピックRe: iMX6Q SABRE-AI Android M6 LVDS Backlight going off while bootup

iMX6Q SABRE-AI Android M6 LVDS Backlight going off while bootup

Re: iMX6Q SABRE-AI Android M6 LVDS Backlight going off while bootup

Re: iMX6Q SABRE-AI Android M6 LVDS Backlight going off while bootup