OMAPDSS: Fix crash with DT boot

When booting with DT, there's a crash when omapfb is probed. This is
caused by the fact that omapdss+DT is not yet supported, and thus
omapdss is not probed at all. On the other hand, omapfb is always
probed. When omapfb tries to use omapdss, there's a NULL pointer
dereference crash. The same error should most likely happen with omapdrm
and omap_vout also.

To fix this, add an "initialized" state to omapdss. When omapdss has
been probed, it's marked as initialized. omapfb, omapdrm and omap_vout
check this state when they are probed to see that omapdss is actually
there.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/video/omap2/omapfb/omapfb-main.c b/drivers/video/omap2/omapfb/omapfb-main.c
index 717f13a93351..bb5f9fee3659 100644
--- a/drivers/video/omap2/omapfb/omapfb-main.c
+++ b/drivers/video/omap2/omapfb/omapfb-main.c
@@ -2416,6 +2416,9 @@ static int __init omapfb_probe(struct platform_device *pdev)
 
         DBG("omapfb_probe\n");
 
+        if (omapdss_is_initialized() == false)
+                return -EPROBE_DEFER;
+
         if (pdev->num_resources != 0) {
                 dev_err(&pdev->dev, "probed for an unknown device\n");
                 r = -ENODEV;