[PATCH 3.16 037/254] mfd: twl4030-audio: Fix sibling-node lookup

Ben Hutchings
2018-02-28T15:38:59Z

From: Johan Hovold <johan@kernel.org>

commit 0a423772de2f3d7b00899987884f62f63ae00dcb upstream.

A helper purported to look up a child node based on its name was using
the wrong of-helper and ended up prematurely freeing the parent of-node
while leaking any matching node.

To make things worse, any matching node would not even necessarily be a
child node as the whole device tree was searched depth-first starting at
the parent.

Fixes: 019a7e6b7b31 ("mfd: twl4030-audio: Add DT support")
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/mfd/twl4030-audio.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

--- a/drivers/mfd/twl4030-audio.c
+++ b/drivers/mfd/twl4030-audio.c
@@ -159,13 +159,18 @@ unsigned int twl4030_audio_get_mclk(void
EXPORT_SYMBOL_GPL(twl4030_audio_get_mclk);

static bool twl4030_audio_has_codec(struct twl4030_audio_data *pdata,
- struct device_node *node)
+ struct device_node *parent)
{
+ struct device_node *node;
+
if (pdata && pdata->codec)
return true;

- if (of_find_node_by_name(node, "codec"))
+ node = of_get_child_by_name(parent, "codec");
+ if (node) {
+ of_node_put(node);
return true;
+ }

return false;
}