[PATCH] video/imxfb: fix suspend when screen is blanked

["Eric Bénard" <eric@eukrea.com>]

if the screen is blanked when suspending, the clock is already disabled,
leading to the following log :
WARNING: at arch/arm/plat-mxc/clock.c:59 __clk_disable+0x68/0x74()
Modules linked in:
[<c002d200>] (unwind_backtrace+0x0/0xf8) from [<c0046008>] (warn_slowpath_common+0x48/0x78)
[<c0046008>] (warn_slowpath_common+0x48/0x78) from [<c0031e28>] (__clk_disable+0x68/0x74)
[<c0031e28>] (__clk_disable+0x68/0x74) from [<c0031ddc>] (__clk_disable+0x1c/0x74)
[<c0031ddc>] (__clk_disable+0x1c/0x74) from [<c0031e58>] (clk_disable+0x24/0x34)
[<c0031e58>] (clk_disable+0x24/0x34) from [<c019808c>] (imxfb_disable_controller+0x38/0x48)
[<c019808c>] (imxfb_disable_controller+0x38/0x48) from [<c01980b0>] (imxfb_suspend+0x14/0x1c)

Signed-off-by: Eric Bénard <eric@eukrea.com>
Cc: kernel@pengutronix.de
Cc: u.kleine-koenig@pengutronix.de
Cc: linux-fbdev@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
---
 drivers/video/imxfb.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/video/imxfb.c b/drivers/video/imxfb.c
index b4b6dec..6cbfbff 100644
--- a/drivers/video/imxfb.c
+++ b/drivers/video/imxfb.c
@@ -597,8 +597,8 @@ static int imxfb_suspend(struct platform_device *dev, pm_message_t state)
 	struct imxfb_info *fbi = info->par;
 
 	pr_debug("%s\n", __func__);
-
-	imxfb_disable_controller(fbi);
+	if (readl(fbi->regs + LCDC_RMCR))
+		imxfb_disable_controller(fbi);
 	return 0;
 }
 
-- 
1.6.3.3