From e8dd273d199f5bbe295a8e3d8b777c5505b6b2e1 Mon Sep 17 00:00:00 2001 From: Salah Triki Date: Thu, 17 Sep 2026 14:00:52 +0100 Subject: iio: proximity: isl29501: Fix return type of isl29501_register_write isl29501_register_write() was returning a u32 instead of an int. Since the function returns negative error codes (such as -ERANGE or return values from i2c_smbus_write_byte_data()), returning an unsigned integer type prevents callers from correctly checking for negative error conditions. Fix this by changing the function return type from u32 to int. This was found through manual code review. Fixes: 1c28799257bc ("iio: light: isl29501: Add support for the ISL29501 ToF sensor.") Signed-off-by: Salah Triki Reviewed-by: Joshua Crofts Cc: stable@vger.kernel.org Signed-off-by: Jonathan Cameron --- lib/once.c | 98 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 98 insertions(+) create mode 100644 lib/once.c (limited to 'lib/once.c') diff --git a/lib/once.c b/lib/once.c new file mode 100644 index 000000000..0a0a91915 --- /dev/null +++ b/lib/once.c @@ -0,0 +1,98 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include + +struct once_work { + struct work_struct work; + struct static_key_true *key; + struct module *module; +}; + +static void once_deferred(struct work_struct *w) +{ + struct once_work *work; + + work = container_of(w, struct once_work, work); + BUG_ON(!static_key_enabled(work->key)); + static_branch_disable(work->key); + module_put(work->module); + kfree(work); +} + +static void once_disable_jump(struct static_key_true *key, struct module *mod) +{ + struct once_work *w; + + w = kmalloc_obj(*w, GFP_ATOMIC); + if (!w) + return; + + INIT_WORK(&w->work, once_deferred); + w->key = key; + w->module = mod; + __module_get(mod); + schedule_work(&w->work); +} + +static DEFINE_SPINLOCK(once_lock); + +bool __do_once_start(bool *done, unsigned long *flags) + __acquires(once_lock) +{ + spin_lock_irqsave(&once_lock, *flags); + if (*done) { + spin_unlock_irqrestore(&once_lock, *flags); + /* Keep sparse happy by restoring an even lock count on + * this lock. In case we return here, we don't call into + * __do_once_done but return early in the DO_ONCE() macro. + */ + __acquire(once_lock); + return false; + } + + return true; +} +EXPORT_SYMBOL(__do_once_start); + +void __do_once_done(bool *done, struct static_key_true *once_key, + unsigned long *flags, struct module *mod) + __releases(once_lock) +{ + *done = true; + spin_unlock_irqrestore(&once_lock, *flags); + once_disable_jump(once_key, mod); +} +EXPORT_SYMBOL(__do_once_done); + +static DEFINE_MUTEX(once_mutex); + +bool __do_once_sleepable_start(bool *done) + __acquires(once_mutex) +{ + mutex_lock(&once_mutex); + if (*done) { + mutex_unlock(&once_mutex); + /* Keep sparse happy by restoring an even lock count on + * this mutex. In case we return here, we don't call into + * __do_once_done but return early in the DO_ONCE_SLEEPABLE() macro. + */ + __acquire(once_mutex); + return false; + } + + return true; +} +EXPORT_SYMBOL(__do_once_sleepable_start); + +void __do_once_sleepable_done(bool *done, struct static_key_true *once_key, + struct module *mod) + __releases(once_mutex) +{ + *done = true; + mutex_unlock(&once_mutex); + once_disable_jump(once_key, mod); +} +EXPORT_SYMBOL(__do_once_sleepable_done); -- cgit v1.3.1