rfkill: detect bogus double-registering (v2)

Detect and abort with -EEXIST if rfkill_register is called twice on the
same rfkill struct.  And WARN_ON(it) for good measure.

While at it, flag when we are adding the first switch of a type, we will
need that information later.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Henrique de Moraes Holschuh 2008-08-02 15:10:57 -03:00 коммит произвёл John W. Linville
Родитель c94c93da90
Коммит 02589f6051
1 изменённых файлов: 28 добавлений и 1 удалений

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@ -525,17 +525,44 @@ static struct class rfkill_class = {
.dev_uevent = rfkill_dev_uevent,
};
static int rfkill_check_duplicity(const struct rfkill *rfkill)
{
struct rfkill *p;
unsigned long seen[BITS_TO_LONGS(RFKILL_TYPE_MAX)];
memset(seen, 0, sizeof(seen));
list_for_each_entry(p, &rfkill_list, node) {
if (p == rfkill) {
WARN_ON(1);
return -EEXIST;
}
set_bit(p->type, seen);
}
/* 0: first switch of its kind */
return test_bit(rfkill->type, seen);
}
static int rfkill_add_switch(struct rfkill *rfkill)
{
int error;
mutex_lock(&rfkill_mutex);
error = rfkill_check_duplicity(rfkill);
if (error < 0)
goto unlock_out;
rfkill_toggle_radio(rfkill, rfkill_states[rfkill->type], 0);
list_add_tail(&rfkill->node, &rfkill_list);
error = 0;
unlock_out:
mutex_unlock(&rfkill_mutex);
return 0;
return error;
}
static void rfkill_remove_switch(struct rfkill *rfkill)