[media] saa7115: Trust that V4L2 core will fill the mask

Instead of using V4L2_STD_ALL when no standard is detected,
trust that the maximum allowed standards are already filled by
the V4L2 core. It is better this way, as the bridge and/or the audio
decoder may have some extra restrictions to some video standards.

This also allow other devices like audio and tuners to contribute to
standards detection, when they support such feature.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/saa7115.c

@@ -1346,17 +1346,23 @@ static int saa711x_querystd(struct v4l2_subdev *sd, v4l2_std_id *std)
 	struct saa711x_state *state = to_state(sd);
 	int reg1f, reg1e;
 
+	/*
+	 * The V4L2 core already initializes std with all supported
+	 * Standards. All driver needs to do is to mask it, to remove
+	 * standards that don't apply from the mask
+	 */
+
 	reg1f = saa711x_read(sd, R_1F_STATUS_BYTE_2_VD_DEC);
 	v4l2_dbg(1, debug, sd, "Status byte 2 (0x1f)=0x%02x\n", reg1f);
-	if (reg1f & 0x40) {
-		/* horizontal/vertical not locked */
-		*std = V4L2_STD_ALL;
+
+	/* horizontal/vertical not locked */
+	if (reg1f & 0x40)
 		goto ret;
-	}
+
 	if (reg1f & 0x20)
-		*std = V4L2_STD_525_60;
+		*std &= V4L2_STD_525_60;
 	else
-		*std = V4L2_STD_625_50;
+		*std &= V4L2_STD_625_50;
 
 	if (state->ident != V4L2_IDENT_SAA7115)
 		goto ret;
@@ -1381,7 +1387,6 @@ static int saa711x_querystd(struct v4l2_subdev *sd, v4l2_std_id *std)
 		break;
 	default:
 		/* Can't detect anything */
-		*std = V4L2_STD_ALL;
 		break;
 	}