From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from ec2-52-27-115-49.us-west-2.compute.amazonaws.com ([52.27.115.49]:55352 "EHLO osg.samsung.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751152AbdH0MSP (ORCPT ); Sun, 27 Aug 2017 08:18:15 -0400 Date: Sun, 27 Aug 2017 09:18:07 -0300 From: Mauro Carvalho Chehab To: Daniel Scheller Cc: linux-media@vger.kernel.org, mchehab@kernel.org, jasmin@anw.at, rjkm@metzlerbros.de Subject: Re: [PATCH] [media] dvb-frontends/mxl5xx: fix lock check order Message-ID: <20170827091807.404a9907@vento.lan> In-Reply-To: <20170820104545.6596-1-d.scheller.oss@gmail.com> References: <20170820104545.6596-1-d.scheller.oss@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Em Sun, 20 Aug 2017 12:45:45 +0200 Daniel Scheller escreveu: > From: Daniel Scheller > Always add a description at the patch. > Signed-off-by: Daniel Scheller > --- > When the mxl5xx driver together with the ddbridge glue gets merged ([1]), > this one should go in aswell - this fix is part of the dddvb-0.9.31 > release. > > drivers/media/dvb-frontends/mxl5xx.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/media/dvb-frontends/mxl5xx.c b/drivers/media/dvb-frontends/mxl5xx.c > index 676c96c216c3..d9136d67f5d4 100644 > --- a/drivers/media/dvb-frontends/mxl5xx.c > +++ b/drivers/media/dvb-frontends/mxl5xx.c > @@ -638,13 +638,14 @@ static int tune(struct dvb_frontend *fe, bool re_tune, > state->tune_time = jiffies; > return 0; > } > - if (*status & FE_HAS_LOCK) > - return 0; > > r = read_status(fe, status); > if (r) > return r; > > + if (*status & FE_HAS_LOCK) > + return 0; > + > return 0; That's stupid! it will return 0 on all situations, no matter if FE_HAS_LOCK or not. So, no need for the if. Anyway, IMHO, either the original code is right and it needs to use a previously cached value (with sounds weird to me, although it is possible), or the logic is utterly broken, and we should, instead, apply the enclosed patch. > if (r) > return r; > } > Thanks, Mauro [PATCH RFC] media: mxl5xx: fix tuning logic The tuning logic is broken with regards to status report: it relies on a previously-cached value that may not be valid if retuned. Change the logic to always read the status. Signed-off-by: Mauro Carvalho Chehab diff --git a/drivers/media/dvb-frontends/mxl5xx.c b/drivers/media/dvb-frontends/mxl5xx.c index 676c96c216c3..4b449a6943c5 100644 --- a/drivers/media/dvb-frontends/mxl5xx.c +++ b/drivers/media/dvb-frontends/mxl5xx.c @@ -636,16 +636,9 @@ static int tune(struct dvb_frontend *fe, bool re_tune, if (r) return r; state->tune_time = jiffies; - return 0; } - if (*status & FE_HAS_LOCK) - return 0; - r = read_status(fe, status); - if (r) - return r; - - return 0; + return read_status(fe, status); } static enum fe_code_rate conv_fec(enum MXL_HYDRA_FEC_E fec)