[media] saa7191: fix querystd

Return V4L2_STD_UNKNOWN if no signal is detected.
Otherwise AND the standard mask with the detected standards.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 8 insertions, 6 deletions

diff --git a/drivers/media/i2c/saa7191.c b/drivers/media/i2c/saa7191.c
index 08dcaecbeb98..606a4baf944d 100644
--- a/drivers/media/i2c/saa7191.c
+++ b/drivers/media/i2c/saa7191.c
@@ -271,7 +271,7 @@ static int saa7191_querystd(struct v4l2_subdev *sd, v4l2_std_id *norm)
 
         dprintk("SAA7191 extended signal auto-detection...\n");
 
-        *norm = V4L2_STD_NTSC | V4L2_STD_PAL | V4L2_STD_SECAM;
+        *norm &= V4L2_STD_NTSC | V4L2_STD_PAL | V4L2_STD_SECAM;
         stdc &= ~SAA7191_STDC_SECS;
         ctl3 &= ~(SAA7191_CTL3_FSEL);
 
@@ -302,7 +302,7 @@ static int saa7191_querystd(struct v4l2_subdev *sd, v4l2_std_id *norm)
         if (status & SAA7191_STATUS_FIDT) {
                 /* 60Hz signal -> NTSC */
                 dprintk("60Hz signal: NTSC\n");
-                *norm = V4L2_STD_NTSC;
+                *norm &= V4L2_STD_NTSC;
                 return 0;
         }
 
@@ -324,12 +324,13 @@ static int saa7191_querystd(struct v4l2_subdev *sd, v4l2_std_id *norm)
         if (status & SAA7191_STATUS_FIDT) {
                 dprintk("No 50Hz signal\n");
                 saa7191_s_std(sd, old_norm);
-                return -EAGAIN;
+                *norm = V4L2_STD_UNKNOWN;
+                return 0;
         }
 
         if (status & SAA7191_STATUS_CODE) {
                 dprintk("PAL\n");
-                *norm = V4L2_STD_PAL;
+                *norm &= V4L2_STD_PAL;
                 return saa7191_s_std(sd, old_norm);
         }
 
@@ -349,18 +350,19 @@ static int saa7191_querystd(struct v4l2_subdev *sd, v4l2_std_id *norm)
         /* not 50Hz ? */
         if (status & SAA7191_STATUS_FIDT) {
                 dprintk("No 50Hz signal\n");
-                err = -EAGAIN;
+                *norm = V4L2_STD_UNKNOWN;
                 goto out;
         }
 
         if (status & SAA7191_STATUS_CODE) {
                 /* Color detected -> SECAM */
                 dprintk("SECAM\n");
-                *norm = V4L2_STD_SECAM;
+                *norm &= V4L2_STD_SECAM;
                 return saa7191_s_std(sd, old_norm);
         }
 
         dprintk("No color detected with SECAM - Going back to PAL.\n");
+        *norm = V4L2_STD_UNKNOWN;
 
 out:
         return saa7191_s_std(sd, old_norm);