Re: [PATCH v3 1/5] gpiolib: cdev: relocate debounce_period_us from struct gpio_desc

Andy Shevchenko
2023-12-15T16:35:19Z

On Fri, Dec 15, 2023 at 10:38:01AM +0800, Kent Gibson wrote:
> Store the debounce period for a requested line locally, rather than in
> the debounce_period_us field in the gpiolib struct gpio_desc.
>
> Add a global tree of lines containing supplemental line information
> to make the debounce period available to be reported by the
> GPIO_V2_GET_LINEINFO_IOCTL and the line change notifier.

LGTM, a few minor comments below.

...

> +/*

(now you can have a kernel doc :-)

> + * a rbtree of the struct lines containing supplemental info.
> + * Used to populate gpio_v2_line_info with cdev specific fields not contained
> + * in the struct gpio_desc.
> + * A line is determined to contain supplemental information by
> + * line_is_supplemental().
> + */
> +static struct rb_root supinfo_tree = RB_ROOT;
> +/* covers supinfo_tree */
> +DEFINE_SPINLOCK(supinfo_lock);

Shouldn't this also be static?

...

> + guard(spinlock)(&supinfo_lock);

+ cleanup.h ?

...

> +static void supinfo_to_lineinfo(struct gpio_desc *desc,
> + struct gpio_v2_line_info *info)
> +{
> + struct gpio_v2_line_attribute *attr;
> + struct line *line;
> +
> + guard(spinlock)(&supinfo_lock);
> +
> + line = supinfo_find(desc);
> + if (line) {

if (!line)
return;

?

> + attr = &info->attrs[info->num_attrs];
> + attr->id = GPIO_V2_LINE_ATTR_ID_DEBOUNCE;
> + attr->debounce_period_us = READ_ONCE(line->debounce_period_us);
> + info->num_attrs++;
> + }
> +}

--
With Best Regards,
Andy Shevchenko