On Thu, Dec 14, 2023 at 05:58:11PM +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. ... > +/* > + * 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 { > + /* a rbtree of the struct lines containing the supplemental info */ > + struct rb_root tree; > + /* covers tree */ > + spinlock_t lock; > +} supinfo; ... > +static void supinfo_init(void) > +{ > + supinfo.tree = RB_ROOT; > + spin_lock_init(&supinfo.lock); > +} Can it be done statically? supinfo = { .tree = RB_ROOT, .lock = __SPIN_LOCK_UNLOCKED(supinfo.lock), }; ... > +static int __init gpiolib_cdev_init(void) > +{ > + supinfo_init(); > + return 0; > +} A comment why it's postcore initcall? /* postcore initcall is chosen because ... */ > +postcore_initcall(gpiolib_cdev_init); -- With Best Regards, Andy Shevchenko