video/hdmi: Reject illegal picture aspect ratios

AVI infoframe can only carry none, 4:3, or 16:9 picture aspect
ratios. Return an error if the user asked for something different.

Cc: Shashank Sharma <shashank.sharma@intel.com>
Cc: "Lin, Jia" <lin.a.jia@intel.com>
Cc: Akashdeep Sharma <akashdeep.sharma@intel.com>
Cc: Jim Bride <jim.bride@linux.intel.com>
Cc: Jose Abreu <Jose.Abreu@synopsys.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Emil Velikov <emil.l.velikov@gmail.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Hans Verkuil <hans.verkuil@cisco.com>
Cc: linux-media@vger.kernel.org
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NJose Abreu <joabreu@synopsys.com>
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1525777785-9740-6-git-send-email-ankit.k.nautiyal@intel.com

drivers/video/hdmi.c

@@ -93,6 +93,9 @@ ssize_t hdmi_avi_infoframe_pack(struct hdmi_avi_infoframe *frame, void *buffer,
 	if (size < length)
 		return -ENOSPC;
 
+	if (frame->picture_aspect > HDMI_PICTURE_ASPECT_16_9)
+		return -EINVAL;
+
 	memset(buffer, 0, size);
 
 	ptr[0] = frame->type;