[PATCH] iio: adc: dln2-adc: initialize local struct before using it

[PATCH] iio: adc: dln2-adc: initialize local struct before using it

[Martin Kepplinger]

struct data is defined and declared locally. Initiliazation has to be done
manually, so let's add that.

Signed-off-by: Martin Kepplinger <martink@posteo.de>
---

This is more of a question actually! Did you have in mind that data is
not initialized here? If so, please drop this patch. This is just in case
you implicitely expected data to be zero.


 drivers/iio/adc/dln2-adc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/adc/dln2-adc.c b/drivers/iio/adc/dln2-adc.c
index ab8d6aed5085..452330075b67 100644
--- a/drivers/iio/adc/dln2-adc.c
+++ b/drivers/iio/adc/dln2-adc.c
@@ -489,7 +489,7 @@ static irqreturn_t dln2_adc_trigger_h(int irq, void *p)
 	struct {
 		__le16 values[DLN2_ADC_MAX_CHANNELS];
 		int64_t timestamp_space;
-	} data;
+	} data = { 0 };
 	struct dln2_adc_get_all_vals dev_data;
 	struct dln2_adc *dln2 = iio_priv(indio_dev);
 	const struct dln2_adc_demux_table *t;
-- 
2.11.0

Re: [PATCH] iio: adc: dln2-adc: initialize local struct before using it

[Jonathan Cameron]

On Sun, 10 Sep 2017 14:45:01 +0200
Martin Kepplinger <martink@posteo.de> wrote:

> struct data is defined and declared locally. Initiliazation has to be done
> manually, so let's add that.
> 
> Signed-off-by: Martin Kepplinger <martink@posteo.de>
> ---
> 
> This is more of a question actually! Did you have in mind that data is
> not initialized here? If so, please drop this patch. This is just in case
> you implicitely expected data to be zero.
> 

I don't think it matters as the whole structure is filled by the later
code anyway..  Am I missing a path where it isn't?

Jonathan

> 
>  drivers/iio/adc/dln2-adc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/adc/dln2-adc.c b/drivers/iio/adc/dln2-adc.c
> index ab8d6aed5085..452330075b67 100644
> --- a/drivers/iio/adc/dln2-adc.c
> +++ b/drivers/iio/adc/dln2-adc.c
> @@ -489,7 +489,7 @@ static irqreturn_t dln2_adc_trigger_h(int irq, void *p)
>  	struct {
>  		__le16 values[DLN2_ADC_MAX_CHANNELS];
>  		int64_t timestamp_space;
> -	} data;
> +	} data = { 0 };
>  	struct dln2_adc_get_all_vals dev_data;
>  	struct dln2_adc *dln2 = iio_priv(indio_dev);
>  	const struct dln2_adc_demux_table *t;

Re: [PATCH] iio: adc: dln2-adc: initialize local struct before using it

[kbuild test robot]

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Hi Martin,

[auto build test WARNING on iio/togreg]
[also build test WARNING on next-20170911]
[cannot apply to v4.13]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Martin-Kepplinger/iio-adc-dln2-adc-initialize-local-struct-before-using-it/20170912-064250
base:   https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git togreg
config: tile-allyesconfig (attached as .config)
compiler: tilegx-linux-gcc (GCC) 4.6.2
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=tile 

All warnings (new ones prefixed by >>):

   drivers/iio/adc/dln2-adc.c: In function 'dln2_adc_trigger_h':
>> drivers/iio/adc/dln2-adc.c:492:2: warning: missing braces around initializer [-Wmissing-braces]
   drivers/iio/adc/dln2-adc.c:492:2: warning: (near initialization for 'data.values') [-Wmissing-braces]

vim +492 drivers/iio/adc/dln2-adc.c

   484	
   485	static irqreturn_t dln2_adc_trigger_h(int irq, void *p)
   486	{
   487		struct iio_poll_func *pf = p;
   488		struct iio_dev *indio_dev = pf->indio_dev;
   489		struct {
   490			__le16 values[DLN2_ADC_MAX_CHANNELS];
   491			int64_t timestamp_space;
 > 492		} data = { 0 };
   493		struct dln2_adc_get_all_vals dev_data;
   494		struct dln2_adc *dln2 = iio_priv(indio_dev);
   495		const struct dln2_adc_demux_table *t;
   496		int ret, i;
   497	
   498		mutex_lock(&dln2->mutex);
   499		ret = dln2_adc_read_all(dln2, &dev_data);
   500		mutex_unlock(&dln2->mutex);
   501		if (ret < 0)
   502			goto done;
   503	
   504		/* Demux operation */
   505		for (i = 0; i < dln2->demux_count; ++i) {
   506			t = &dln2->demux[i];
   507			memcpy((void *)data.values + t->to,
   508			       (void *)dev_data.values + t->from, t->length);
   509		}
   510	
   511		/* Zero padding space between values and timestamp */
   512		if (dln2->ts_pad_length)
   513			memset((void *)data.values + dln2->ts_pad_offset,
   514			       0, dln2->ts_pad_length);
   515	
   516		iio_push_to_buffers_with_timestamp(indio_dev, &data,
   517						   iio_get_time_ns(indio_dev));
   518	
   519	done:
   520		iio_trigger_notify_done(indio_dev->trig);
   521		return IRQ_HANDLED;
   522	}
   523	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

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Re: [PATCH] iio: adc: dln2-adc: initialize local struct before using it

[Martin Kepplinger]

Am 12.09.2017 03:32 schrieb kbuild test robot:
> Hi Martin,
> 
> [auto build test WARNING on iio/togreg]
> [also build test WARNING on next-20170911]
> [cannot apply to v4.13]
> [if your patch is applied to the wrong git tree, please drop us a note
> to help improve the system]
> 
> url:
> https://github.com/0day-ci/linux/commits/Martin-Kepplinger/iio-adc-dln2-adc-initialize-local-struct-before-using-it/20170912-064250
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git 
> togreg
> config: tile-allyesconfig (attached as .config)
> compiler: tilegx-linux-gcc (GCC) 4.6.2
> reproduce:
>         wget
> https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross
> -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # save the attached .config to linux build tree
>         make.cross ARCH=tile
> 
> All warnings (new ones prefixed by >>):
> 
>    drivers/iio/adc/dln2-adc.c: In function 'dln2_adc_trigger_h':
>>> drivers/iio/adc/dln2-adc.c:492:2: warning: missing braces around 
>>> initializer [-Wmissing-braces]
>    drivers/iio/adc/dln2-adc.c:492:2: warning: (near initialization for
> 'data.values') [-Wmissing-braces]
> 
> vim +492 drivers/iio/adc/dln2-adc.c
> 
>    484
>    485	static irqreturn_t dln2_adc_trigger_h(int irq, void *p)
>    486	{
>    487		struct iio_poll_func *pf = p;
>    488		struct iio_dev *indio_dev = pf->indio_dev;
>    489		struct {
>    490			__le16 values[DLN2_ADC_MAX_CHANNELS];
>    491			int64_t timestamp_space;
>  > 492		} data = { 0 };


ok :) I guess

    } data = {{ 0 }};

would be ok for gcc in this case. How far has this patch gone? Do you 
want a fix
on top or the patch re-done? Or do you just do it yourself?

thanks,

                   martin

Re: [PATCH] iio: adc: dln2-adc: initialize local struct before using it

[Jonathan Cameron]

On Tue, 12 Sep 2017 09:01:27 +0200
Martin Kepplinger <martink@posteo.de> wrote:

> Am 12.09.2017 03:32 schrieb kbuild test robot:
> > Hi Martin,
> > 
> > [auto build test WARNING on iio/togreg]
> > [also build test WARNING on next-20170911]
> > [cannot apply to v4.13]
> > [if your patch is applied to the wrong git tree, please drop us a note
> > to help improve the system]
> > 
> > url:
> > https://github.com/0day-ci/linux/commits/Martin-Kepplinger/iio-adc-dln2-adc-initialize-local-struct-before-using-it/20170912-064250
> > base:   https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git 
> > togreg
> > config: tile-allyesconfig (attached as .config)
> > compiler: tilegx-linux-gcc (GCC) 4.6.2
> > reproduce:
> >         wget
> > https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross
> > -O ~/bin/make.cross
> >         chmod +x ~/bin/make.cross
> >         # save the attached .config to linux build tree
> >         make.cross ARCH=tile
> > 
> > All warnings (new ones prefixed by >>):
> > 
> >    drivers/iio/adc/dln2-adc.c: In function 'dln2_adc_trigger_h':  
> >>> drivers/iio/adc/dln2-adc.c:492:2: warning: missing braces around 
> >>> initializer [-Wmissing-braces]  
> >    drivers/iio/adc/dln2-adc.c:492:2: warning: (near initialization for
> > 'data.values') [-Wmissing-braces]
> > 
> > vim +492 drivers/iio/adc/dln2-adc.c
> > 
> >    484
> >    485	static irqreturn_t dln2_adc_trigger_h(int irq, void *p)
> >    486	{
> >    487		struct iio_poll_func *pf = p;
> >    488		struct iio_dev *indio_dev = pf->indio_dev;
> >    489		struct {
> >    490			__le16 values[DLN2_ADC_MAX_CHANNELS];
> >    491			int64_t timestamp_space;  
> >  > 492		} data = { 0 };  
> 
> 
> ok :) I guess
> 
>     } data = {{ 0 }};
> 
> would be ok for gcc in this case. How far has this patch gone? Do you 
> want a fix
> on top or the patch re-done? Or do you just do it yourself?
>
I'm  unconvinced the patch is necessary as I think all elements of
that structure are initialized anyway before they are used.

I might be missing a code path where that isn't true though so
feel free to point one out!

Jonathan
 
> thanks,
> 
>                    martin