Message-ID: <0d5acf26f560b82da9d77a2c9d46042d8c4cd5d1.camel@gmail.com>
Subject: Re: [PATCH 05/17] media: atomisp: pci: fix inverted error check for
 ia_css_mipi_is_source_port_valid()
From:   Tsuchiya Yuto <kitakar@gmail.com>
To:     Mauro Carvalho Chehab <mchehab@kernel.org>
Cc:     Dan Carpenter <dan.carpenter@oracle.com>,
        Hans de Goede <hdegoede@redhat.com>,
        Patrik Gfeller <patrik.gfeller@gmail.com>,
        Sakari Ailus <sakari.ailus@linux.intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Hans Verkuil <hverkuil-cisco@xs4all.nl>,
        Aline Santana Cordeiro <alinesantanacordeiro@gmail.com>,
        Yang Yingliang <yangyingliang@huawei.com>,
        Dinghao Liu <dinghao.liu@zju.edu.cn>,
        Deepak R Varma <drv@mailo.com>,
        Alex Dewar <alex.dewar90@gmail.com>,
        linux-media@vger.kernel.org, linux-staging@lists.linux.dev,
        linux-kernel@vger.kernel.org
Date:   Wed, 01 Dec 2021 21:15:10 +0900
In-Reply-To: <20211108163536.07bd2282@sal.lan>
References: <20211017161958.44351-1-kitakar@gmail.com>
         <20211017161958.44351-6-kitakar@gmail.com> <20211102113332.GC2794@kadam>
         <ed17420d96bd302479b528f7ae8694ff9cd2e72a.camel@gmail.com>
         <20211108151455.GI2001@kadam>
         <efaf74b587e5e31403895cd5af88852402fe92ec.camel@gmail.com>
         <20211108163536.07bd2282@sal.lan>
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On Mon, 2021-11-08 at 16:35 +0000, Mauro Carvalho Chehab wrote:
> Em Tue, 09 Nov 2021 00:25:52 +0900
> Tsuchiya Yuto <kitakar@gmail.com> escreveu:
> 
> > <removed Alan from Cc as the mail address not reachable>
> > 
> > On Mon, 2021-11-08 at 18:14 +0300, Dan Carpenter wrote:
> > > On Tue, Nov 09, 2021 at 12:00:29AM +0900, Tsuchiya Yuto wrote:  
> > > > On Tue, 2021-11-02 at 14:33 +0300, Dan Carpenter wrote:  
> > > > > On Mon, Oct 18, 2021 at 01:19:45AM +0900, Tsuchiya Yuto wrote:  
> > > > > > The function ia_css_mipi_is_source_port_valid() returns true if the port
> > > > > > is valid. So, we can't use the existing err variable as is.
> > > > > > 
> > > > > > To fix this issue while reusing that variable, invert the return value
> > > > > > when assigning it to the variable.
> > > > > > 
> > > > > > Fixes: 3c0538fbad9f ("media: atomisp: get rid of most checks for ISP2401 version")
> > > > > > Signed-off-by: Tsuchiya Yuto <kitakar@gmail.com>
> > > > > > ---
> > > > > >  .../staging/media/atomisp/pci/sh_css_mipi.c   | 24 ++++++++++++-------
> > > > > >  1 file changed, 15 insertions(+), 9 deletions(-)
> > > > > > 
> > > > > > diff --git a/drivers/staging/media/atomisp/pci/sh_css_mipi.c b/drivers/staging/media/atomisp/pci/sh_css_mipi.c
> > > > > > index 65fc93c5d56b..c1f2f6151c5f 100644
> > > > > > --- a/drivers/staging/media/atomisp/pci/sh_css_mipi.c
> > > > > > +++ b/drivers/staging/media/atomisp/pci/sh_css_mipi.c
> > > > > > @@ -423,10 +423,12 @@ allocate_mipi_frames(struct ia_css_pipe *pipe,
> > > > > >  		return 0; /* AM TODO: Check  */
> > > > > >  	}
> > > > > >  
> > > > > > -	if (!IS_ISP2401)
> > > > > > +	if (!IS_ISP2401) {
> > > > > >  		port = (unsigned int)pipe->stream->config.source.port.port;
> > > > > > -	else
> > > > > > -		err = ia_css_mipi_is_source_port_valid(pipe, &port);
> > > > > > +	} else {
> > > > > > +		/* Returns true if port is valid. So, invert it */
> > > > > > +		err = !ia_css_mipi_is_source_port_valid(pipe, &port);  
> > > > > 
> > > > > Don't invert it...  This isn't supposed to return 1 on failure it's
> > > > > supposed to return negative error codes.  
> > > > 
> > > > You mean I should instead modify the return value of
> > > > ia_css_mipi_is_source_port_valid() ?
> > > >   
> > > 
> > > No.  ia_css_mipi_is_source_port_valid() is fine.  It has a boolean name
> > > so returning bool is fine.  What I'm saying is that allocate_mipi_frames()
> > > should do:
> > > 
> > > 	if (!ia_css_mipi_is_source_port_valid(pipe, &port))
> > > 		err = -EINVAL;
> > > 
> > > Otherwise it returns negative error codes and 1 on failure.  
> > 
> > Ah, I see! Thank you. I feel I'm a stupid... I'll do so in v2.
> 
> I would prefer if you could send such changes on new patches.

I'm a little bit too late, sorry. For the record, the return value issue
pointed out here is already gone with patch ("media: atomisp: sh_css_mipi:
cleanup the code") [1]. Thanks!

[1] https://lore.kernel.org/linux-media/b541d4c9923154be7ae0518d01ce994acbef3f9b.1637142905.git.mchehab+huawei@kernel.org/