In using the AM335x EVM I've noticed that after some time of inactivity the LCD seems to turn itself off. I need to disable this functionality so I poked around a bit trying to find out why it was doing this in the first place.
When I was reading on the LCDC Driver's Guide: http://processors.wiki.ti.com/index.php/AM335x_LCD_Controller_Driver%27s_Guide
I saw this line:
"Framebuffer console blankes out after blanking interval....Default blankinterval is 10 minutes"
And in there it stated that "unblanking" can happen with this command:
$echo "0" > /sys/class/graphics/fb0/blank
And if I want to keep it permanently "unblanked" I can append to the boot arguments consoleblank=0. I gave this a try updating my boot command to:
U-Boot# setenv mmc_args 'run bootargs_defaults;setenv bootargs ${bootargs} root=${mmc_root} rootfstype=${mmc_root_fs_type} ip=169.254.0.2 consoleblank=0'
But when I do this it seems the LCD comes up powered off... I've also noted when the screen goes off echoing "0" to fb0/blank doesn't seem to do anything.. whereas echoing "4" seems to turn it back on (the screen slowly turns on, almost fading on)
Are these the correct commands? Should "0" in fact be turning ON the display? If so why am I not seeing that effect?