[PATCH 0/2] Staging:iio:adc:Prefer using BIT macro

[PATCH 0/2] Staging:iio:adc:Prefer using BIT macro

[Bhumika Goyal]

This patchset replaces bit shifting on 1 with the BIT(x) macro.
This was done with coccinelle:
@@ int g; @@ 
-(1 << g) 
+BIT(g)

Bhumika Goyal (2):
  Staging:iio:Prefer using BIT macro
  Staging: iio: adc: Prefer using the BIT macro

 drivers/staging/iio/adc/ad7280a.c | 4 ++--
 drivers/staging/iio/adc/ad7816.c  | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

-- 
1.9.1

[PATCH 1/2] Staging:iio:Prefer using BIT macro

[Bhumika Goyal]

This patch replaces bit shifting on 1 with the BIT(x) macro.
This was done with coccinelle:
 @@ int g; @@
-(1 << g)
+BIT(g)

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
---
 drivers/staging/iio/adc/ad7816.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/iio/adc/ad7816.c b/drivers/staging/iio/adc/ad7816.c
index 2226051..f631012 100644
--- a/drivers/staging/iio/adc/ad7816.c
+++ b/drivers/staging/iio/adc/ad7816.c
@@ -222,7 +222,7 @@ static ssize_t ad7816_show_value(struct device *dev,
 		value = (s8)((data >> AD7816_TEMP_FLOAT_OFFSET) - 103);
 		data &= AD7816_TEMP_FLOAT_MASK;
 		if (value < 0)
-			data = (1 << AD7816_TEMP_FLOAT_OFFSET) - data;
+			data = BIT(AD7816_TEMP_FLOAT_OFFSET) - data;
 		return sprintf(buf, "%d.%.2d\n", value, data * 25);
 	}
 	return sprintf(buf, "%u\n", data);
-- 
1.9.1

[PATCH 2/2] Staging: iio: adc: Prefer using the BIT macro

[Bhumika Goyal]

This patch replaces bit shifting on 1 with the BIT(x) macro.

This was done with coccinelle:

@@ int g; @@

-(1 << g)
+BIT(g)

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
---
 drivers/staging/iio/adc/ad7280a.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/iio/adc/ad7280a.c b/drivers/staging/iio/adc/ad7280a.c
index 0c73bce..ccf3157 100644
--- a/drivers/staging/iio/adc/ad7280a.c
+++ b/drivers/staging/iio/adc/ad7280a.c
@@ -117,7 +117,7 @@
  */
 #define POLYNOM		0x2F
 #define POLYNOM_ORDER	8
-#define HIGHBIT		(1 << (POLYNOM_ORDER - 1))
+#define HIGHBIT		BIT((POLYNOM_ORDER - 1))
 
 struct ad7280_state {
 	struct spi_device		*spi;
@@ -388,7 +388,7 @@ static ssize_t ad7280_show_balance_sw(struct device *dev,
 
 	return sprintf(buf, "%d\n",
 		       !!(st->cb_mask[this_attr->address >> 8] &
-		       (1 << ((this_attr->address & 0xFF) + 2))));
+		       BIT(((this_attr->address & 0xFF) + 2))));
 }
 
 static ssize_t ad7280_store_balance_sw(struct device *dev,
-- 
1.9.1

Re: [PATCH 1/2] Staging:iio:Prefer using BIT macro

[Lars-Peter Clausen]

On 02/08/2016 07:48 AM, Bhumika Goyal wrote:
> This patch replaces bit shifting on 1 with the BIT(x) macro.
> This was done with coccinelle:
>  @@ int g; @@
> -(1 << g)
> +BIT(g)
> 
> Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>

Hi,

Thanks for the patch.

> ---
>  drivers/staging/iio/adc/ad7816.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/iio/adc/ad7816.c b/drivers/staging/iio/adc/ad7816.c
> index 2226051..f631012 100644
> --- a/drivers/staging/iio/adc/ad7816.c
> +++ b/drivers/staging/iio/adc/ad7816.c
> @@ -222,7 +222,7 @@ static ssize_t ad7816_show_value(struct device *dev,
>  		value = (s8)((data >> AD7816_TEMP_FLOAT_OFFSET) - 103);
>  		data &= AD7816_TEMP_FLOAT_MASK;
>  		if (value < 0)
> -			data = (1 << AD7816_TEMP_FLOAT_OFFSET) - data;
> +			data = BIT(AD7816_TEMP_FLOAT_OFFSET) - data;


But in this case this is a false positive. The intended semantic meaning
here is 2**... not BIT(...). Using BIT() here in my opinion only causes
confusion.

>  		return sprintf(buf, "%d.%.2d\n", value, data * 25);
>  	}
>  	return sprintf(buf, "%u\n", data);
> 

Re: [PATCH 2/2] Staging: iio: adc: Prefer using the BIT macro

[Lars-Peter Clausen]

On 02/08/2016 07:48 AM, Bhumika Goyal wrote:
> This patch replaces bit shifting on 1 with the BIT(x) macro.
> 
> This was done with coccinelle:
> 
> @@ int g; @@
> 
> -(1 << g)
> +BIT(g)
> 
> Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>

Hi,

Thanks for the patch. This looks good.

> ---
>  drivers/staging/iio/adc/ad7280a.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/staging/iio/adc/ad7280a.c b/drivers/staging/iio/adc/ad7280a.c
> index 0c73bce..ccf3157 100644
> --- a/drivers/staging/iio/adc/ad7280a.c
> +++ b/drivers/staging/iio/adc/ad7280a.c
> @@ -117,7 +117,7 @@
>   */
>  #define POLYNOM		0x2F
>  #define POLYNOM_ORDER	8
> -#define HIGHBIT		(1 << (POLYNOM_ORDER - 1))
> +#define HIGHBIT		BIT((POLYNOM_ORDER - 1))

But please drop the extra brackets and resend the patch.

>  
>  struct ad7280_state {
>  	struct spi_device		*spi;
> @@ -388,7 +388,7 @@ static ssize_t ad7280_show_balance_sw(struct device *dev,
>  
>  	return sprintf(buf, "%d\n",
>  		       !!(st->cb_mask[this_attr->address >> 8] &
> -		       (1 << ((this_attr->address & 0xFF) + 2))));
> +		       BIT(((this_attr->address & 0xFF) + 2))));

Same here.

Re: [PATCH 1/2] Staging:iio:Prefer using BIT macro

[Andy Shevchenko]

On Mon, Feb 8, 2016 at 11:14 AM, Lars-Peter Clausen <lars@metafoo.de> wrote:
> On 02/08/2016 07:48 AM, Bhumika Goyal wrote:

>>               value = (s8)((data >> AD7816_TEMP_FLOAT_OFFSET) - 103);
>>               data &= AD7816_TEMP_FLOAT_MASK;
>>               if (value < 0)
>> -                     data = (1 << AD7816_TEMP_FLOAT_OFFSET) - data;
>> +                     data = BIT(AD7816_TEMP_FLOAT_OFFSET) - data;
>
>
> But in this case this is a false positive. The intended semantic meaning
> here is 2**... not BIT(...). Using BIT() here in my opinion only causes
> confusion.

+1. Here clearly the intention is to change sign of the value which
fits less than 32/16/8 bits. 1 << OFFSET represents '-0'.

-- 
With Best Regards,
Andy Shevchenko