[media] mb86a20s: apply mask to val after checking for read failure

Appling the mask 0x0f to the immediate return of the call to
mb86a20s_readreg will always result in a positive value, meaning that the
check of ret < 0 will never work.  Instead, check for a -ve return value
first, and then mask val with 0x0f.

Kudos to Mauro Carvalho Chehab for spotting the mistake in my original fix.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/media/dvb-frontends/mb86a20s.c b/drivers/media/dvb-frontends/mb86a20s.c
index fb88dddaf3a3..41325328a22e 100644
--- a/drivers/media/dvb-frontends/mb86a20s.c
+++ b/drivers/media/dvb-frontends/mb86a20s.c
@@ -301,10 +301,11 @@ static int mb86a20s_read_status(struct dvb_frontend *fe, enum fe_status *status)
 
         *status = 0;
 
-        val = mb86a20s_readreg(state, 0x0a) & 0xf;
+        val = mb86a20s_readreg(state, 0x0a);
         if (val < 0)
                 return val;
 
+        val &= 0xf;
         if (val >= 2)
                 *status |= FE_HAS_SIGNAL;