Merge tag 'imx-fixes-3.8-3' of git://git.linaro.org/people/shawnguo/linux-2.6 into fixes

From Shawn Guo:

This is yet another critical imxfb fixes held off by absence of FB
maintainer for some time.

* tag 'imx-fixes-3.8-3' of git://git.linaro.org/people/shawnguo/linux-2.6:
  video: imxfb: Do not crash on reboot

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/video/imxfb.c b/drivers/video/imxfb.c
index 600f6f9987cc..0abf2bf20836 100644
--- a/drivers/video/imxfb.c
+++ b/drivers/video/imxfb.c
@@ -139,6 +139,7 @@ struct imxfb_info {
         struct clk              *clk_ahb;
         struct clk              *clk_per;
         enum imxfb_type         devtype;
+        bool                    enabled;
 
         /*
          * These are the addresses we mapped
@@ -536,6 +537,10 @@ static void imxfb_exit_backlight(struct imxfb_info *fbi)
 
 static void imxfb_enable_controller(struct imxfb_info *fbi)
 {
+
+        if (fbi->enabled)
+                return;
+
         pr_debug("Enabling LCD controller\n");
 
         writel(fbi->screen_dma, fbi->regs + LCDC_SSA);
@@ -556,6 +561,7 @@ static void imxfb_enable_controller(struct imxfb_info *fbi)
         clk_prepare_enable(fbi->clk_ipg);
         clk_prepare_enable(fbi->clk_ahb);
         clk_prepare_enable(fbi->clk_per);
+        fbi->enabled = true;
 
         if (fbi->backlight_power)
                 fbi->backlight_power(1);
@@ -565,6 +571,9 @@ static void imxfb_enable_controller(struct imxfb_info *fbi)
 
 static void imxfb_disable_controller(struct imxfb_info *fbi)
 {
+        if (!fbi->enabled)
+                return;
+
         pr_debug("Disabling LCD controller\n");
 
         if (fbi->backlight_power)
@@ -575,6 +584,7 @@ static void imxfb_disable_controller(struct imxfb_info *fbi)
         clk_disable_unprepare(fbi->clk_per);
         clk_disable_unprepare(fbi->clk_ipg);
         clk_disable_unprepare(fbi->clk_ahb);
+        fbi->enabled = false;
 
         writel(0, fbi->regs + LCDC_RMCR);
 }