Re: [PATCH 1/4] gpiolib: cdev: relocate debounce_period_us from struct gpio_desc

[Andy Shevchenko <andy@kernel.org>]

On Wed, Dec 13, 2023 at 11:59:26PM +0800, Kent Gibson wrote:
> On Wed, Dec 13, 2023 at 04:40:12PM +0100, Bartosz Golaszewski wrote:
> > On Wed, Dec 13, 2023 at 3:27 PM Kent Gibson <warthog618@gmail.com> wrote:
> > > On Wed, Dec 13, 2023 at 03:54:53PM +0200, Andy Shevchenko wrote:
> > > > On Tue, Dec 12, 2023 at 01:42:50PM +0800, Kent Gibson wrote:

...

> > > > > +static struct supinfo supinfo;
> > > >
> > > > Why supinfo should be a struct to begin with? Seems to me as an unneeded
> > > > complication.
> >
> > I think we should keep it as a struct but defined the following way:
> >
> > struct {
> >     spinlock_t lock;
> >     struct rb_root tree;
> > } supinfo;
> 
> That is what I meant be merging the struct definition with the variable
> definition.  Or is there some other way to completely do away with the
> struct that I'm missing?

Look at the top of gpiolib.c:

static DEFINE_MUTEX(gpio_lookup_lock);
static LIST_HEAD(gpio_lookup_list);

In the similar way you can simply do

static DEFINE_SPINLOCK(gpio_sup_lock);
static struct rb_root gpio_sup_tree;

> > > Yeah, that is a hangover from an earlier iteration where supinfo was
> > > contained in other object rather than being a global.
> > > Could merge the struct definition into the variable now.

-- 
With Best Regards,
Andy Shevchenko