[PATCH] staging: comedi: drivers: usbduxsigma: Removed variables that is never used

[PATCH] staging: comedi: drivers: usbduxsigma: Removed variables that is never used

[Rickard Strandqvist]

Variable ar assigned a value that is never used.
I have also removed all the code that thereby serves no purpose.

This was found using a static code analysis program called cppcheck

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
---
 drivers/staging/comedi/drivers/usbduxsigma.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/staging/comedi/drivers/usbduxsigma.c b/drivers/staging/comedi/drivers/usbduxsigma.c
index dc19435..7b80887 100644
--- a/drivers/staging/comedi/drivers/usbduxsigma.c
+++ b/drivers/staging/comedi/drivers/usbduxsigma.c
@@ -215,7 +215,6 @@ static void usbduxsigma_ai_handle_urb(struct comedi_device *dev,
 	struct usbduxsigma_private *devpriv = dev->private;
 	struct comedi_async *async = s->async;
 	struct comedi_cmd *cmd = &async->cmd;
-	unsigned int dio_state;
 	uint32_t val;
 	int ret;
 	int i;
@@ -225,7 +224,7 @@ static void usbduxsigma_ai_handle_urb(struct comedi_device *dev,
 		devpriv->ai_counter = devpriv->ai_timer;
 
 		/* get the state of the dio pins to allow external trigger */
-		dio_state = be32_to_cpu(devpriv->in_buf[0]);
+		be32_to_cpu(devpriv->in_buf[0]);
 
 		/* get the data from the USB bus and hand it over to comedi */
 		for (i = 0; i < cmd->chanlist_len; i++) {
-- 
1.7.10.4

Re: [PATCH] staging: comedi: drivers: usbduxsigma: Removed variables that is never used

[Ian Abbott]

On 28/01/15 22:39, Rickard Strandqvist wrote:
> Variable ar assigned a value that is never used.
> I have also removed all the code that thereby serves no purpose.
>
> This was found using a static code analysis program called cppcheck
>
> Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
> ---
>   drivers/staging/comedi/drivers/usbduxsigma.c |    3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/staging/comedi/drivers/usbduxsigma.c b/drivers/staging/comedi/drivers/usbduxsigma.c
> index dc19435..7b80887 100644
> --- a/drivers/staging/comedi/drivers/usbduxsigma.c
> +++ b/drivers/staging/comedi/drivers/usbduxsigma.c
> @@ -215,7 +215,6 @@ static void usbduxsigma_ai_handle_urb(struct comedi_device *dev,
>   	struct usbduxsigma_private *devpriv = dev->private;
>   	struct comedi_async *async = s->async;
>   	struct comedi_cmd *cmd = &async->cmd;
> -	unsigned int dio_state;
>   	uint32_t val;
>   	int ret;
>   	int i;
> @@ -225,7 +224,7 @@ static void usbduxsigma_ai_handle_urb(struct comedi_device *dev,
>   		devpriv->ai_counter = devpriv->ai_timer;
>
>   		/* get the state of the dio pins to allow external trigger */
> -		dio_state = be32_to_cpu(devpriv->in_buf[0]);
> +		be32_to_cpu(devpriv->in_buf[0]);

That line produces a compiler warning.  The line can be removed as the 
call to be32_to_cpu() has no side-effects.  The "/* get the state ..." 
comment line can also be removed as it is only associated with this line.

Perhaps Bernd intended to use dio_state for something here, but I'm not 
sure what.

>
>   		/* get the data from the USB bus and hand it over to comedi */
>   		for (i = 0; i < cmd->chanlist_len; i++) {
>


-- 
-=( Ian Abbott @ MEV Ltd.    E-mail: <abbotti@mev.co.uk> )=-
-=(                          Web: http://www.mev.co.uk/  )=-

Re: [PATCH] staging: comedi: drivers: usbduxsigma: Removed variables that is never used

[Bernd Porr]

Indeed. It can be completely removed. I was intending to speed up DIO 
reads during async acquisition but I decided against it because it would 
create unpredictable latencies.

Thanks Ian for flagging it!

/Bernd

Ian Abbott wrote:
> On 28/01/15 22:39, Rickard Strandqvist wrote:
>> Variable ar assigned a value that is never used.
>> I have also removed all the code that thereby serves no purpose.
>>
>> This was found using a static code analysis program called cppcheck
>>
>> Signed-off-by: Rickard Strandqvist 
>> <rickard_strandqvist@spectrumdigital.se>
>> ---
>>   drivers/staging/comedi/drivers/usbduxsigma.c |    3 +--
>>   1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/drivers/staging/comedi/drivers/usbduxsigma.c 
>> b/drivers/staging/comedi/drivers/usbduxsigma.c
>> index dc19435..7b80887 100644
>> --- a/drivers/staging/comedi/drivers/usbduxsigma.c
>> +++ b/drivers/staging/comedi/drivers/usbduxsigma.c
>> @@ -215,7 +215,6 @@ static void usbduxsigma_ai_handle_urb(struct 
>> comedi_device *dev,
>>       struct usbduxsigma_private *devpriv = dev->private;
>>       struct comedi_async *async = s->async;
>>       struct comedi_cmd *cmd = &async->cmd;
>> -    unsigned int dio_state;
>>       uint32_t val;
>>       int ret;
>>       int i;
>> @@ -225,7 +224,7 @@ static void usbduxsigma_ai_handle_urb(struct 
>> comedi_device *dev,
>>           devpriv->ai_counter = devpriv->ai_timer;
>>
>>           /* get the state of the dio pins to allow external trigger */
>> -        dio_state = be32_to_cpu(devpriv->in_buf[0]);
>> +        be32_to_cpu(devpriv->in_buf[0]);
> 
> That line produces a compiler warning.  The line can be removed as the 
> call to be32_to_cpu() has no side-effects.  The "/* get the state ..." 
> comment line can also be removed as it is only associated with this line.
> 
> Perhaps Bernd intended to use dio_state for something here, but I'm not 
> sure what.
> 
>>
>>           /* get the data from the USB bus and hand it over to comedi */
>>           for (i = 0; i < cmd->chanlist_len; i++) {
>>
> 
> 

-- 
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