diff mbox

[1/4] iio: adc: xilinx: Rename 'channels' variable name to 'iio_xadc_channels'

Message ID 1531912331-26431-2-git-send-email-manish.narani@xilinx.com (mailing list archive)
State New, archived
Headers show

Commit Message

Manish Narani July 18, 2018, 11:12 a.m. UTC
This patch fix the following checkpatch warning in xadc driver.
- Reusing the krealloc arg is almost always a bug.

Renamed the 'channels' variable as 'iio_xadc_channels' to fix the above
warning.

Signed-off-by: Manish Narani <manish.narani@xilinx.com>
---
 drivers/iio/adc/xilinx-xadc-core.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

Comments

Lars-Peter Clausen July 18, 2018, 11:18 a.m. UTC | #1
On 07/18/2018 01:12 PM, Manish Narani wrote:
> This patch fix the following checkpatch warning in xadc driver.
> - Reusing the krealloc arg is almost always a bug.
> 
> Renamed the 'channels' variable as 'iio_xadc_channels' to fix the above
> warning.
> 

This is a bug in checkpatch and should be fixed in checkpatch. The code is
not actually re-using the parameter. channels and xadc_channels are
independent variables, just checkpatch somehow does not realize this.

> Signed-off-by: Manish Narani <manish.narani@xilinx.com>
> ---
>  drivers/iio/adc/xilinx-xadc-core.c | 16 +++++++++-------
>  1 file changed, 9 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/iio/adc/xilinx-xadc-core.c b/drivers/iio/adc/xilinx-xadc-core.c
> index d4f21d1..27b45df 100644
> --- a/drivers/iio/adc/xilinx-xadc-core.c
> +++ b/drivers/iio/adc/xilinx-xadc-core.c
> @@ -1040,7 +1040,7 @@ static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
>  	unsigned int *conf)
>  {
>  	struct xadc *xadc = iio_priv(indio_dev);
> -	struct iio_chan_spec *channels, *chan;
> +	struct iio_chan_spec *iio_xadc_channels, *chan;
>  	struct device_node *chan_node, *child;
>  	unsigned int num_channels;
>  	const char *external_mux;
> @@ -1083,12 +1083,13 @@ static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
>  		*conf |= XADC_CONF0_MUX | XADC_CONF0_CHAN(ext_mux_chan);
>  	}
>  
> -	channels = kmemdup(xadc_channels, sizeof(xadc_channels), GFP_KERNEL);
> -	if (!channels)
> +	iio_xadc_channels = kmemdup(xadc_channels, sizeof(xadc_channels),
> +				    GFP_KERNEL);
> +	if (!iio_xadc_channels)
>  		return -ENOMEM;
>  
>  	num_channels = 9;
> -	chan = &channels[9];
> +	chan = &iio_xadc_channels[9];
>  
>  	chan_node = of_get_child_by_name(np, "xlnx,channels");
>  	if (chan_node) {
> @@ -1119,11 +1120,12 @@ static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
>  	of_node_put(chan_node);
>  
>  	indio_dev->num_channels = num_channels;
> -	indio_dev->channels = krealloc(channels, sizeof(*channels) *
> -					num_channels, GFP_KERNEL);
> +	indio_dev->channels = krealloc(iio_xadc_channels,
> +				       sizeof(*iio_xadc_channels) *
> +				       num_channels, GFP_KERNEL);
>  	/* If we can't resize the channels array, just use the original */
>  	if (!indio_dev->channels)
> -		indio_dev->channels = channels;
> +		indio_dev->channels = iio_xadc_channels;
>  
>  	return 0;
>  }
>
Manish Narani July 18, 2018, 11:52 a.m. UTC | #2
Hi Lars,

> -----Original Message-----
> From: Lars-Peter Clausen [mailto:lars@metafoo.de]
> Sent: Wednesday, July 18, 2018 4:49 PM
> To: Manish Narani <MNARANI@xilinx.com>; jic23@kernel.org;
> knaack.h@gmx.de; pmeerw@pmeerw.net; Michal Simek
> <michals@xilinx.com>; linux-iio@vger.kernel.org; linux-arm-
> kernel@lists.infradead.org; linux-kernel@vger.kernel.org
> Cc: Anirudha Sarangi <anirudh@xilinx.com>; Srinivas Goud
> <sgoud@xilinx.com>; Joe Perches <joe@perches.com>
> Subject: Re: [PATCH 1/4] iio: adc: xilinx: Rename 'channels' variable name to
> 'iio_xadc_channels'
> 
> On 07/18/2018 01:12 PM, Manish Narani wrote:
> > This patch fix the following checkpatch warning in xadc driver.
> > - Reusing the krealloc arg is almost always a bug.
> >
> > Renamed the 'channels' variable as 'iio_xadc_channels' to fix the
> > above warning.
> >
> 
> This is a bug in checkpatch and should be fixed in checkpatch. The code is not
> actually re-using the parameter. channels and xadc_channels are independent
> variables, just checkpatch somehow does not realize this.
I agree with you on this. Initially I presumed the checkpatch to be giving genuine
warning but now I am sure that this is certainly the checkpatch script issue.
In that case should we keep this code change?
Please suggest.

Thanks,
Manish

> 
> > Signed-off-by: Manish Narani <manish.narani@xilinx.com>
> > ---
> >  drivers/iio/adc/xilinx-xadc-core.c | 16 +++++++++-------
> >  1 file changed, 9 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/iio/adc/xilinx-xadc-core.c
> > b/drivers/iio/adc/xilinx-xadc-core.c
> > index d4f21d1..27b45df 100644
> > --- a/drivers/iio/adc/xilinx-xadc-core.c
> > +++ b/drivers/iio/adc/xilinx-xadc-core.c
> > @@ -1040,7 +1040,7 @@ static int xadc_parse_dt(struct iio_dev *indio_dev,
> struct device_node *np,
> >  	unsigned int *conf)
> >  {
> >  	struct xadc *xadc = iio_priv(indio_dev);
> > -	struct iio_chan_spec *channels, *chan;
> > +	struct iio_chan_spec *iio_xadc_channels, *chan;
> >  	struct device_node *chan_node, *child;
> >  	unsigned int num_channels;
> >  	const char *external_mux;
> > @@ -1083,12 +1083,13 @@ static int xadc_parse_dt(struct iio_dev
> *indio_dev, struct device_node *np,
> >  		*conf |= XADC_CONF0_MUX |
> XADC_CONF0_CHAN(ext_mux_chan);
> >  	}
> >
> > -	channels = kmemdup(xadc_channels, sizeof(xadc_channels),
> GFP_KERNEL);
> > -	if (!channels)
> > +	iio_xadc_channels = kmemdup(xadc_channels, sizeof(xadc_channels),
> > +				    GFP_KERNEL);
> > +	if (!iio_xadc_channels)
> >  		return -ENOMEM;
> >
> >  	num_channels = 9;
> > -	chan = &channels[9];
> > +	chan = &iio_xadc_channels[9];
> >
> >  	chan_node = of_get_child_by_name(np, "xlnx,channels");
> >  	if (chan_node) {
> > @@ -1119,11 +1120,12 @@ static int xadc_parse_dt(struct iio_dev
> *indio_dev, struct device_node *np,
> >  	of_node_put(chan_node);
> >
> >  	indio_dev->num_channels = num_channels;
> > -	indio_dev->channels = krealloc(channels, sizeof(*channels) *
> > -					num_channels, GFP_KERNEL);
> > +	indio_dev->channels = krealloc(iio_xadc_channels,
> > +				       sizeof(*iio_xadc_channels) *
> > +				       num_channels, GFP_KERNEL);
> >  	/* If we can't resize the channels array, just use the original */
> >  	if (!indio_dev->channels)
> > -		indio_dev->channels = channels;
> > +		indio_dev->channels = iio_xadc_channels;
> >
> >  	return 0;
> >  }
> >
Michal Simek July 19, 2018, 8:22 a.m. UTC | #3
On 18.7.2018 13:18, Lars-Peter Clausen wrote:
> On 07/18/2018 01:12 PM, Manish Narani wrote:
>> This patch fix the following checkpatch warning in xadc driver.
>> - Reusing the krealloc arg is almost always a bug.
>>
>> Renamed the 'channels' variable as 'iio_xadc_channels' to fix the above
>> warning.
>>
> 
> This is a bug in checkpatch and should be fixed in checkpatch. The code is
> not actually re-using the parameter. channels and xadc_channels are
> independent variables, just checkpatch somehow does not realize this.

I think it should be fine to have this patch in tree. Change in commit
message to reflect this should be enough. But that's just view.

Thanks,
Michal
Jonathan Cameron July 21, 2018, 4:18 p.m. UTC | #4
On Thu, 19 Jul 2018 10:22:07 +0200
Michal Simek <michal.simek@xilinx.com> wrote:

> On 18.7.2018 13:18, Lars-Peter Clausen wrote:
> > On 07/18/2018 01:12 PM, Manish Narani wrote:  
> >> This patch fix the following checkpatch warning in xadc driver.
> >> - Reusing the krealloc arg is almost always a bug.
> >>
> >> Renamed the 'channels' variable as 'iio_xadc_channels' to fix the above
> >> warning.
> >>  
> > 
> > This is a bug in checkpatch and should be fixed in checkpatch. The code is
> > not actually re-using the parameter. channels and xadc_channels are
> > independent variables, just checkpatch somehow does not realize this.  
> 
> I think it should be fine to have this patch in tree. Change in commit
> message to reflect this should be enough. But that's just view.

Let's wait and see if Joe has time to take a look at this.  Might be better
to fix checkpatch if it's not too hard!

Jonathan
> 
> Thanks,
> Michal
> --
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Joe Perches July 21, 2018, 4:22 p.m. UTC | #5
On Sat, 2018-07-21 at 17:18 +0100, Jonathan Cameron wrote:
> On Thu, 19 Jul 2018 10:22:07 +0200
> Michal Simek <michal.simek@xilinx.com> wrote:
> 
> > On 18.7.2018 13:18, Lars-Peter Clausen wrote:
> > > On 07/18/2018 01:12 PM, Manish Narani wrote:  
> > > > This patch fix the following checkpatch warning in xadc driver.
> > > > - Reusing the krealloc arg is almost always a bug.
> > > > 
> > > > Renamed the 'channels' variable as 'iio_xadc_channels' to fix the above
> > > > warning.
> > > >  
> > > 
> > > This is a bug in checkpatch and should be fixed in checkpatch. The code is
> > > not actually re-using the parameter. channels and xadc_channels are
> > > independent variables, just checkpatch somehow does not realize this.  
> > 
> > I think it should be fine to have this patch in tree. Change in commit
> > message to reflect this should be enough. But that's just view.
> 
> Let's wait and see if Joe has time to take a look at this.  Might be better
> to fix checkpatch if it's not too hard!

I submitted a proposed patch.
I believe it works.

https://patchwork.kernel.org/patch/10533011/
Jonathan Cameron July 21, 2018, 4:33 p.m. UTC | #6
On Sat, 21 Jul 2018 09:22:05 -0700
Joe Perches <joe@perches.com> wrote:

> On Sat, 2018-07-21 at 17:18 +0100, Jonathan Cameron wrote:
> > On Thu, 19 Jul 2018 10:22:07 +0200
> > Michal Simek <michal.simek@xilinx.com> wrote:
> >   
> > > On 18.7.2018 13:18, Lars-Peter Clausen wrote:  
> > > > On 07/18/2018 01:12 PM, Manish Narani wrote:    
> > > > > This patch fix the following checkpatch warning in xadc driver.
> > > > > - Reusing the krealloc arg is almost always a bug.
> > > > > 
> > > > > Renamed the 'channels' variable as 'iio_xadc_channels' to fix the above
> > > > > warning.
> > > > >    
> > > > 
> > > > This is a bug in checkpatch and should be fixed in checkpatch. The code is
> > > > not actually re-using the parameter. channels and xadc_channels are
> > > > independent variables, just checkpatch somehow does not realize this.    
> > > 
> > > I think it should be fine to have this patch in tree. Change in commit
> > > message to reflect this should be enough. But that's just view.  
> > 
> > Let's wait and see if Joe has time to take a look at this.  Might be better
> > to fix checkpatch if it's not too hard!  
> 
> I submitted a proposed patch.
> I believe it works.
> 
> https://patchwork.kernel.org/patch/10533011/
> 
Thanks! Should have known you would already have it covered :)
My perl foo goes no where near figuring out how that magic works!

Jonathan
diff mbox

Patch

diff --git a/drivers/iio/adc/xilinx-xadc-core.c b/drivers/iio/adc/xilinx-xadc-core.c
index d4f21d1..27b45df 100644
--- a/drivers/iio/adc/xilinx-xadc-core.c
+++ b/drivers/iio/adc/xilinx-xadc-core.c
@@ -1040,7 +1040,7 @@  static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
 	unsigned int *conf)
 {
 	struct xadc *xadc = iio_priv(indio_dev);
-	struct iio_chan_spec *channels, *chan;
+	struct iio_chan_spec *iio_xadc_channels, *chan;
 	struct device_node *chan_node, *child;
 	unsigned int num_channels;
 	const char *external_mux;
@@ -1083,12 +1083,13 @@  static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
 		*conf |= XADC_CONF0_MUX | XADC_CONF0_CHAN(ext_mux_chan);
 	}
 
-	channels = kmemdup(xadc_channels, sizeof(xadc_channels), GFP_KERNEL);
-	if (!channels)
+	iio_xadc_channels = kmemdup(xadc_channels, sizeof(xadc_channels),
+				    GFP_KERNEL);
+	if (!iio_xadc_channels)
 		return -ENOMEM;
 
 	num_channels = 9;
-	chan = &channels[9];
+	chan = &iio_xadc_channels[9];
 
 	chan_node = of_get_child_by_name(np, "xlnx,channels");
 	if (chan_node) {
@@ -1119,11 +1120,12 @@  static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
 	of_node_put(chan_node);
 
 	indio_dev->num_channels = num_channels;
-	indio_dev->channels = krealloc(channels, sizeof(*channels) *
-					num_channels, GFP_KERNEL);
+	indio_dev->channels = krealloc(iio_xadc_channels,
+				       sizeof(*iio_xadc_channels) *
+				       num_channels, GFP_KERNEL);
 	/* If we can't resize the channels array, just use the original */
 	if (!indio_dev->channels)
-		indio_dev->channels = channels;
+		indio_dev->channels = iio_xadc_channels;
 
 	return 0;
 }