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clk: fix new_parent dereference before null check

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Commit 71472c0 (clk: add support for clock reparent on set_rate) added a
dereference of the new_parent pointer in clk_reparent(), but as detected
by smatch clk_reparent() later checks whether new_parent is NULL.

The dereference was in order to clear the new parent's new_child pointer
to avoid duplicate POST_RATE_CHANGE notifications, so clearly isn't
necessary if the new parent is NULL, so move it inside the "if
(new_parent)" block.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
This commit is contained in:
James Hogan 2013-08-29 12:10:51 +01:00 committed by Mike Turquette
parent 08442ce993
commit 903efc553f
1 changed files with 7 additions and 6 deletions
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13
drivers/clk/clk.c
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@ -1108,16 +1108,17 @@ static u8 clk_fetch_parent_index(struct clk *clk, struct clk *parent)
static void clk_reparent(struct clk *clk, struct clk *new_parent)
{
/* avoid duplicate POST_RATE_CHANGE notifications */
if (new_parent->new_child == clk)
new_parent->new_child = NULL;
hlist_del(&clk->child_node);
if (new_parent)
if (new_parent) {
/* avoid duplicate POST_RATE_CHANGE notifications */
if (new_parent->new_child == clk)
new_parent->new_child = NULL;
hlist_add_head(&clk->child_node, &new_parent->children);
else
} else {
hlist_add_head(&clk->child_node, &clk_orphan_list);
}
clk->parent = new_parent;
}