Re: [PATCH 1/6] staging: media: intel-ipu3: replace bit shifts with BIT() macro

[Sakari Ailus]

Hi Greg,

On Mon, Apr 12, 2021 at 11:49:43AM +0200, Greg KH wrote:
> On Mon, Apr 12, 2021 at 12:42:30PM +0300, Sakari Ailus wrote:
> > Hi Mitali,
> > 
> > On Mon, Apr 12, 2021 at 04:38:39AM +0530, Mitali Borkar wrote:
> > > Added #include <linux/bitops.h> and replaced bit shifts by BIT() macro.
> > > This BIT() macro from linux/bitops.h is used to define IPU3_UAPI_GRID_Y_START_EN
> > > and IPU3_UAPI_AWB_RGBS_THR_B_* bitmask.
> > > Use of macro is better and neater. It maintains consistency.
> > > Reported by checkpatch.
> > > 
> > > Signed-off-by: Mitali Borkar <mitaliborkar810@xxxxxxxxx>
> > > ---
> > >  drivers/staging/media/ipu3/include/intel-ipu3.h | 7 ++++---
> > >  1 file changed, 4 insertions(+), 3 deletions(-)
> > > 
> > > diff --git a/drivers/staging/media/ipu3/include/intel-ipu3.h b/drivers/staging/media/ipu3/include/intel-ipu3.h
> > > index edd8edda0647..589d5ccee3a7 100644
> > > --- a/drivers/staging/media/ipu3/include/intel-ipu3.h
> > > +++ b/drivers/staging/media/ipu3/include/intel-ipu3.h
> > > @@ -5,6 +5,7 @@
> > >  #define __IPU3_UAPI_H
> > >  
> > >  #include <linux/types.h>
> > > +#include <linux/bitops.h>
> > >  
> > >  /* from /drivers/staging/media/ipu3/include/videodev2.h */
> > >  
> > > @@ -22,11 +23,11 @@
> > >  #define IPU3_UAPI_MAX_BUBBLE_SIZE			10
> > >  
> > >  #define IPU3_UAPI_GRID_START_MASK			((1 << 12) - 1)
> > > -#define IPU3_UAPI_GRID_Y_START_EN			(1 << 15)
> > > +#define IPU3_UAPI_GRID_Y_START_EN			BIT(15)
> > 
> > This header is used in user space where you don't have the BIT() macro.
> 
> If that is true, why is it not in a "uapi" subdir within this driver?
> 
> Otherwise it is not obvious at all that this is the case :(

It defines an interface towards the user space and the argument has been a
staging driver shouldn't be doing that (for the lack of ABI stability),
hence leaving it where it is currently.

Also CC Laurent.

-- 
Kind regards,

Sakari Ailus