overo lcd43 touchscreen does not work

[Andy Doan]

confirmed on two kernels:
  linaro 2.6.38 shipped in the 11.05 release
  current 2.6.38 tip: 5983da7 Merge branch 'beagle-fixes' of git://kernel.ubuntu.com/rsalveti/linux-li

There are two DRM issues:

1) A device like Overo's lcd43 display (Samsung LTE430WQ-F0C panel) does not support EDID probing via i2c. The DRM related code tried to account for this but did so incorrectly.

2) The drm_mode_vrefresh function in drivers/gpu/drm/drm_modes.c is returning a value of 59 rather than 60 which causes the code to think the one supported more for this panel is incorrectly configured.

[Andy Doan (doanac)]

I have a proposed patch to fix the first issue of i2c and probing. This has only been test on:

 * Overo + Tobi (using DVI) to verify EDID probing still works
 * Overo + Palo with panel to verify panel can work

in the panel test I had to hack the drm_mode_vrefresh function and add "omapdss.def_disp=lcd43" to the kernel arguments

[Ash Charles (ashcharles)]

I can confirm this bug in linux-linaro-2.6.38 master and have tested Andy's patch with both a DVI monitor attached and a LTE430WQ panel attached. Both types of screens worked although the 4.3" panel showed a vertical bar at one point in the image. It was not necessary to add the "omapdss.def_disp=lcd43" argument.
Note, lgphilips 3.5" panels aren't fixed by this patch.

[Ricardo Salveti (rsalveti)]

Is this fixed already with current TI LT kernel head?

[Andy Doan (doanac)]

On 07/18/2011 12:59 AM, Ricardo Salveti wrote:
> Is this fixed already with current TI LT kernel head?

Yes:
http://git.linaro.org/gitweb?p=people/andygreen/kernel-tilt.git;a=shortlog;h=refs/heads/tilt-linux-linaro-2.6.39

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Chase Qi (chase-qi)]

Migrated to bugzilla: https://bugs.linaro.org/show_bug.cgi?id=576