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 --- drivers/base/map.c | 154 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 154 insertions(+) create mode 100644 drivers/base/map.c (limited to 'drivers/base/map.c') diff --git a/drivers/base/map.c b/drivers/base/map.c new file mode 100644 index 000000000..bde415f93 --- /dev/null +++ b/drivers/base/map.c @@ -0,0 +1,154 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/drivers/base/map.c + * + * (C) Copyright Al Viro 2002,2003 + * + * NOTE: data structure needs to be changed. It works, but for large dev_t + * it will be too slow. It is isolated, though, so these changes will be + * local to that file. + */ + +#include +#include +#include +#include +#include +#include + +struct kobj_map { + struct probe { + struct probe *next; + dev_t dev; + unsigned long range; + struct module *owner; + kobj_probe_t *get; + int (*lock)(dev_t, void *); + void *data; + } *probes[255]; + struct mutex *lock; +}; + +int kobj_map(struct kobj_map *domain, dev_t dev, unsigned long range, + struct module *module, kobj_probe_t *probe, + int (*lock)(dev_t, void *), void *data) +{ + unsigned int n = MAJOR(dev + range - 1) - MAJOR(dev) + 1; + unsigned int index = MAJOR(dev); + unsigned int i; + struct probe *p; + + if (n > 255) + n = 255; + + p = kmalloc_objs(struct probe, n); + if (p == NULL) + return -ENOMEM; + + for (i = 0; i < n; i++, p++) { + p->owner = module; + p->get = probe; + p->lock = lock; + p->dev = dev; + p->range = range; + p->data = data; + } + mutex_lock(domain->lock); + for (i = 0, p -= n; i < n; i++, p++, index++) { + struct probe **s = &domain->probes[index % 255]; + while (*s && (*s)->range < range) + s = &(*s)->next; + p->next = *s; + *s = p; + } + mutex_unlock(domain->lock); + return 0; +} + +void kobj_unmap(struct kobj_map *domain, dev_t dev, unsigned long range) +{ + unsigned int n = MAJOR(dev + range - 1) - MAJOR(dev) + 1; + unsigned int index = MAJOR(dev); + unsigned int i; + struct probe *found = NULL; + + if (n > 255) + n = 255; + + mutex_lock(domain->lock); + for (i = 0; i < n; i++, index++) { + struct probe **s; + for (s = &domain->probes[index % 255]; *s; s = &(*s)->next) { + struct probe *p = *s; + if (p->dev == dev && p->range == range) { + *s = p->next; + if (!found) + found = p; + break; + } + } + } + mutex_unlock(domain->lock); + kfree(found); +} + +struct kobject *kobj_lookup(struct kobj_map *domain, dev_t dev, int *index) +{ + struct kobject *kobj; + struct probe *p; + unsigned long best = ~0UL; + +retry: + mutex_lock(domain->lock); + for (p = domain->probes[MAJOR(dev) % 255]; p; p = p->next) { + struct kobject *(*probe)(dev_t, int *, void *); + struct module *owner; + void *data; + + if (p->dev > dev || p->dev + p->range - 1 < dev) + continue; + if (p->range - 1 >= best) + break; + if (!try_module_get(p->owner)) + continue; + owner = p->owner; + data = p->data; + probe = p->get; + best = p->range - 1; + *index = dev - p->dev; + if (p->lock && p->lock(dev, data) < 0) { + module_put(owner); + continue; + } + mutex_unlock(domain->lock); + kobj = probe(dev, index, data); + /* Currently ->owner protects _only_ ->probe() itself. */ + module_put(owner); + if (kobj) + return kobj; + goto retry; + } + mutex_unlock(domain->lock); + return NULL; +} + +struct kobj_map *kobj_map_init(kobj_probe_t *base_probe, struct mutex *lock) +{ + struct kobj_map *p = kmalloc_obj(struct kobj_map); + struct probe *base = kzalloc_obj(*base); + int i; + + if ((p == NULL) || (base == NULL)) { + kfree(p); + kfree(base); + return NULL; + } + + base->dev = 1; + base->range = ~0; + base->get = base_probe; + for (i = 0; i < 255; i++) + p->probes[i] = base; + p->lock = lock; + return p; +} -- cgit v1.3.1