Merge remote-tracking branch 'airlied/drm-next' into drm-intel-next-queued

Backmerge because:
- Maarten needs latest atomic patches from drm-misc.
- Lionel needs the color manager core patch from drm-misc.
- Ander extracted intel_dpll_mgr.c, we need a backmerge to avoid git
  losing track of things too often (right now it seems ok due to
  cherry-picks).
- Tvrtko needs a stable baseline to apply some large-scale renaming
  patches to i915 GEM code.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/drivers/video/fbdev/imxfb.c b/drivers/video/fbdev/imxfb.c
index cee88603efc9..bb2f1e866020 100644
--- a/drivers/video/fbdev/imxfb.c
+++ b/drivers/video/fbdev/imxfb.c
@@ -902,6 +902,21 @@ static int imxfb_probe(struct platform_device *pdev)
 		goto failed_getclock;
 	}
 
+	/*
+	 * The LCDC controller does not have an enable bit. The
+	 * controller starts directly when the clocks are enabled.
+	 * If the clocks are enabled when the controller is not yet
+	 * programmed with proper register values (enabled at the
+	 * bootloader, for example) then it just goes into some undefined
+	 * state.
+	 * To avoid this issue, let's enable and disable LCDC IPG clock
+	 * so that we force some kind of 'reset' to the LCDC block.
+	 */
+	ret = clk_prepare_enable(fbi->clk_ipg);
+	if (ret)
+		goto failed_getclock;
+	clk_disable_unprepare(fbi->clk_ipg);
+
 	fbi->clk_ahb = devm_clk_get(&pdev->dev, "ahb");
 	if (IS_ERR(fbi->clk_ahb)) {
 		ret = PTR_ERR(fbi->clk_ahb);