imx-common/video: add detect_hdmi

this function is used by several board together with board_video_skip
to detect if hdmi is plugged is order to select the display to use.
So move it in imx-common to share it.

Signed-off-by: Eric Bénard <eric@eukrea.com>

arch/arm/imx-common/video.c

@@ -53,3 +53,13 @@ int board_video_skip(void)
 
 	return 0;
 }
+
+#ifdef CONFIG_IMX_HDMI
+#include <asm/arch/mxc_hdmi.h>
+#include <asm/io.h>
+int detect_hdmi(struct display_info_t const *dev)
+{
+	struct hdmi_regs *hdmi	= (struct hdmi_regs *)HDMI_ARB_BASE_ADDR;
+	return readb(&hdmi->phy_stat0) & HDMI_DVI_STAT;
+}
+#endif

arch/arm/include/asm/imx-common/video.h

@@ -17,4 +17,8 @@ struct display_info_t {
 	struct	fb_videomode mode;
 };
 
+#ifdef CONFIG_IMX_HDMI
+extern int detect_hdmi(struct display_info_t const *dev);
+#endif
+
 #endif