Re: [Outreachy kernel] [PATCH] staging: iio: cdc: add comment to mutex

[Alison Schofield <amsfield22@gmail.com>]

On Tue, Sep 27, 2016 at 10:07:02AM -0700, Alison Schofield wrote:
> On Tue, Sep 27, 2016 at 04:15:12PM +0530, Anchal Jain wrote:
> > Fix the checkpatch.pl issues:
> > CHECK: struct mutes definition without comment
> > 
> > Signed-off-by: Anchal Jain <anchalj109@gmail.com>
> 
> Ahah ;) I've been wondering when someone would get around
> to these.  There are a lot of these CHECK's in IIO.
> 
> Following on Julia & Greg's comments, you do need to 
> explore what the lock is for and give a succinct comment.
> 
> Unfortunately, when you: git grep "struct mutex", even in 
> upstream iio, you won't find too many examples...but you'll
> find a few.  Usually, simply say /* protect <something> */
> 
> Fortunately, in this case, there is a comment for it, just
> in the wrong place - scroll up. That makes your task easier,
> although I still would suggest condensing it to a short phrase that
> fit adjacent to the definition.
> 
> alisons

Although, this change is 'just a comment', if you do a few of them
you'll begin developing an understanding of where and why things
are locked in IIO drivers.  That's where the value is - you are
exploring the code and figuring things out. 

Good patches for honing your patching skills.

alisons


> > ---
> >  drivers/staging/iio/cdc/ad7150.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/staging/iio/cdc/ad7150.c b/drivers/staging/iio/cdc/ad7150.c
> > index f6b9a10..88c6ebe 100644
> > --- a/drivers/staging/iio/cdc/ad7150.c
> > +++ b/drivers/staging/iio/cdc/ad7150.c
> > @@ -78,7 +78,7 @@ struct ad7150_chip_info {
> >  	u8 mag_timeout[2][2];
> >  	int old_state;
> >  	char *conversion_mode;
> > -	struct mutex state_lock;
> > +	struct mutex state_lock; /*generic mutex for cdc and drivers*/
> >  };
> >  
> >  /*
> > -- 
> > 1.9.1
> > 
> > -- 
> > You received this message because you are subscribed to the Google Groups "outreachy-kernel" group.
> > To unsubscribe from this group and stop receiving emails from it, send an email to outreachy-kernel+unsubscribe@googlegroups.com.
> > To post to this group, send email to outreachy-kernel@googlegroups.com.
> > To view this discussion on the web visit https://groups.google.com/d/msgid/outreachy-kernel/20160927104504.GA13155%40life-desktop.
> > For more options, visit https://groups.google.com/d/optout.