Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => iMX233 => Topic started by: Sjef on January 29, 2014, 04:04:40 pm

Title: Composite Video
Post by: Sjef on January 29, 2014, 04:04:40 pm

I would love to get the composite video output to work on my imx233 olinuxino micro board. I'm using the 3.7.1 kernel (koliqi) and u-boot. In kernel config, I enable frame buffer. However, no fb device shows up in /dev. No signal on the cvbs connector.

Searched a lot and basically the only info I can find is that 1) "it doesn't work with 3.x kernels" and 2) "it works with specific (2.6) kernel version build by specific build system (unclear) and specific rootfs (unclear)"

Using kernel 2.6 is not an option for me, neither is use of yocto, openembedded, ARCH linux or any other distribution. Just kernel and buildroot.

Looking at the freescale site, it seems they stuck at 2.6 kernel. Found another git repo with BSP files which is very very confusing to me. Maybe I could somehow use this to enable the composite video?

To anyone reading this, do you know where to find documentation about the composite video output? In my (perhaps way too simple?) view it's a matter of compiling the kernel with the correct device driver. I could even try porting the device driver itself from 2.6 to 3.x. I can't see why this should be difficult. In the end, it's just setting some registers and allocating some memory, right?

But I can't see the wood for the trees. What files constitute this driver in the 2.6 tree? Where are they? Are there dependencies or kernel patches required? Other 'black magic'?

Any pointers greatly appreciated.