[DevKit8000]- 7" LCD display

Hello everyone,

I am trying to get my 7" LCD display to work but am failing at it.
I need some help.

I am new to Linux kernel for the last few months and have been reading as much as I can to try and make this work.
I’m determined to do this but I think I need a little nudge from someone in the right direction.

The dev kit 8000 comes with kernel 2.6.x and I am trying to port it to kernel 3.2.x obtained from R.Nelson.
I created a board file under kernel/arch/arm/mach-omap2/board-rpc.c and a panel-rpc.c under kernel/drivers/video/omap2/displays/…
I created these files with a mix of some DevKit8000 and BeagleBoard files that were in kernel 2.6 and kernel 3.2
I did notice that the code has changed a lot between the two versions.
I am a struggling in learning about omapdss and omapfb but in time I hope to be smarter about it by reading more.

I can confirm that the LCD does work (hardware wise…) from trials and testing using other distro images such as angstrom etc…
I was able to port the old u-boot 1.3.3 to the latest u-boot from DENX.
I built some code pages there under include-config and u-boot/board…
I was able to turn on the DVI and change the screen to Orange while booting the board to u-boot.
I have yet to do this with kernel 3.2

So far, I can boot to u-boot, modify the setenv to match the kernel 3.2, boot the kernel from the SDcard and bring up a file system with busy box.
I have a prompt and the network works.
I was able to get the ads7846 to work because I can get screen garbage when I pinch the LCD screen.
But I can’t seem to get the display and DVI screen to work. :frowning:

I’m sure Im close to the solution and it’s probably right in front of me.
Can someone give me suggestions so I can continue to work at this?

Any help would be appreciated.


Robert Dugas

I should add the following info: from booting - but is not shown in dmesg.
"Error opening /dev/fb0: No such file or directory"

I'm wrestling with this one... from dmesg.
[ 0.405517] omapdss CORE: bus_match. dev display0/rpc_lcd_driver, drv venc
Even though I selected a different lcd driver, it always defaults to "drv venc" used for TV - I believe.
The modifications were done in the kernel board code page.


I dounloaded the latest stable-kernel from RCNelson.
This brought me from kernel ver 3.2.21-x13 to 3.2.27-x14
I am able to get DVI on my DevKit8000 with the Yocto logo as graphics.
I used bootargs= …vram=12M omapfb.mode=dvi:1280x720MR-16@60 omapdss.def_disp=“dvi” omapfb.vram=0:4M,1:4M,2:4M…

However, still no LCD display
Can anyone help me choosing the right bootargs for the LCD?
I tried…
omapfb.mode=dvi:720 omapdss.def_disp=“lcd”

omapfb.mode=lcd:720 omapdss.def_disp=“lcd”

omapfb.mode=lcd omapdss.def_disp=“lcd”



Just an update and my final post on this topic.
I was able to get the touchscreen to work. Here are some of the highlights to watch for.
I created my own custom panel and board pages from existing pages only because I wanted to learn how to do it the hard way.

I started my panel-custom page by modeling the panel-generic-dpi.c page under kernel/drivers/video/omap2/displays
Name your driver here and remember what it is because you’ll need it in the board page.
module_init > omap_dss_driver > .driver.name = “custom_panel”
In the custom_panel_probe function (called from omap_dss_driver.probe = custom_panel_probe), make sure you select the right dpi panel.
In this case, I used the panel_config > timing information from Innolux AT070TN83 because the LCD came with my DevKit8000.
(struct panel_config)custom_dpi_panel.name = “innolux_at070tn83” …note, you’ll need this in the board page.

I started my board-custom page based from multiple board-pages such as devkit8000, omap3evm and omap3beagle under kernel/arch/arm/mach-omap2
Under the function omap_dss_device[ ], you would have 3 devices listed there, lcd, dvi and tv.
In my case, my lcd device (omap_dss_device)custom_lcd_device is setup.
custom_lcd_device.name = “lcd”
custom_lcd_device.driver_name = “custom_panel” < same name as named in the panel-custom page.
custom_lcd_device.data = &lcd_panel >> where you would name it “innolux_at070tn83” as named in the panel-custom page.

from u-boot, in your bootargs, use omapfb.mode=dvi:800x400@60 omapdss.def_disp=“lcd”

I hope this information helps somebody else.
As a newb, I certainly learned a lot while doing the research.
I feel like I graduated or something haha.


Hello Robert and Dave,


I am working on the same "innolux_at070tn83" 7inch display

am able to get the LCD display working but the touch is not working .

I have enabled ADS7846 on android kernel 3.0.still cant get the touch
screen working

Did you make any specific change to the kernel menuconfig wrt to touch



I checked yesterday the Devkit8000/Innolux 7" lcd. The display works,
but the touchscreen was very difficult to operate.
Can you increase the tolerance for the ads7846?

The dvi output was not working because of a missing DCC ic2. I sent a
patch to the linux mailinglist.