[U-Boot] [PATCH] mx6sabresd: Avoid hang when HDMI cable is not connected

[Fabio Estevam]

Since commit d9b894603 (mx6sabresd: Add LVDS splash screen support) the 
following hang happens if the HDMI cable is not connected or the 'panel' 
variable is not set:

U-Boot 2013.10-rc2-12978-g47ac53d-dirty (Sep 11 2013 - 15:07:38)                
                                                                                
CPU:   Freescale i.MX6Q rev1.2 at 792 MHz                                       
Reset cause: POR                                                                
Board: MX6-SabreSD                                                              
DRAM:  1 GiB                                                                    
MMC:   FSL_SDHC: 0, FSL_SDHC: 1, FSL_SDHC: 2
...

Provide a detect_lvds() to avoid the hang.

Reported-by: Pardeep Kumar Singla <b45784 at freescale.com>
Signed-off-by: Fabio Estevam <fabio.estevam at freescale.com>
---
 board/freescale/mx6sabresd/mx6sabresd.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/board/freescale/mx6sabresd/mx6sabresd.c b/board/freescale/mx6sabresd/mx6sabresd.c
index c832bd9..e514529 100644
--- a/board/freescale/mx6sabresd/mx6sabresd.c
+++ b/board/freescale/mx6sabresd/mx6sabresd.c
@@ -263,6 +263,12 @@ static void enable_lvds(struct display_info_t const *dev)
 	       IOMUXC_GPR2_DATA_WIDTH_CH1_24BIT;
 	writel(reg, &iomux->gpr[2]);
 }
+
+static int detect_lvds(struct display_info_t const *dev)
+{
+	return 0;
+}
+
 static struct display_info_t const displays[] = {{
 	.bus	= -1,
 	.addr	= 0,
@@ -287,7 +293,7 @@ static struct display_info_t const displays[] = {{
 	.bus	= -1,
 	.addr	= 0,
 	.pixfmt	= IPU_PIX_FMT_LVDS666,
-	.detect	= NULL,
+	.detect	= detect_lvds,
 	.enable	= enable_lvds,
 	.mode	= {
 		.name           = "Hannstar-XGA",
-- 
1.8.1.2