I’m using Apalis T30 with Linux apalis-t30 3.1.10 #1 SMP PREEMPT Wed Sep 3 19:21:51 CEST 2014 armv7l GNU/Linux and G121X1-L03 LVDS single channel panel. My GPIO configuration is:
cat /sys/kernel/debug/gpio
GPIOs 0-255, tegra-gpio:
gpio-26 (THERMD_ALERT_N ) in hi
gpio-68 (RESET_MOCI_N ) out hi
gpio-111 (HDMI1_HPD ) in hi
gpio-128 (GPIO6 X1-11 ) in lo
gpio-129 (GPIO8 X1-15, FAN ) in lo
gpio-146 (GPIO1 X1-1 ) in lo
gpio-147 (GPIO2 X1-3 ) in lo
gpio-148 (GPIO3 X1-5 ) in lo
gpio-149 (GPIO4 X1-7 ) in lo
gpio-150 (GPIO5 X1-9 ) in lo
gpio-151 (PEX_PERST_N ) out hi
gpio-168 (TOUCH_PEN_INT ) in hi
gpio-169 (KEY_POWER ) in hi
gpio-170 (BKL1_ON ) out hi
gpio-171 (sdhci_cd ) in hi
gpio-216 (LVDS: Single/Dual Ch) out hi
gpio-219 (LVDS: 18/24 Bit Mode) out hi
gpio-220 (LVDS: Output Enable ) out hi
gpio-221 (LVDS: Power Down ) out hi
gpio-222 (LVDS: Clock Polarity) out hi
gpio-223 (LVDS: Colour Mapping) out hi
gpio-225 (LVDS: Swing Mode ) out hi
gpio-226 (LVDS: DDRclk Disable) out hi
gpio-229 (sdhci_cd ) in hi
gpio-232 (SATA1_ACT_N ) out hi
gpio-233 (usb_host_vbus ) out hi
kernel command line:
root@apalis-t30:~# cat /proc/cmdline
core_edp_mv=1300 usb_high_speed=1 ip=off root=/dev/mmcblk0p1 rw,noatime rootfstype=ext3 rootwait gpt gpt_sector=0x7001 igb_mac=00:14:2d:28:72:82 no_console_suspend=1 console=tty1 console=ttyS0,115200n8 debug_uartport=lsport,0 vmalloc=256M mem=2035M@2048M fbmem=12M@4083M fbcon=map:1 video=tegrafb0:640x480-16@60
root@apalis-t30:~# xrandr
Screen 0: minimum 256 x 128, current 1024 x 768, maximum 2048 x 2048
LVDS-1 connected 640x480+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
640x480 61.0*+
HDMI-1 connected 1024x768+0+0 (normal left inverted right x axis y axis) 376mm x 301mm
1280x1024 59.9 + 75.0 60.0
1024x768 75.0* 70.1 60.0
832x624 74.6
800x600 72.2 75.0 60.3 56.2
640x480 75.0 72.8 66.7 59.9
720x400 70.1
but my LVDS display is not working. When my system starts the screen becomes first white, later black, and during X server start its changing colors for a while but with no data on the screen. Can someone help me where to look for faults and how to resolve it?