backlight: max8925_bl: Fix Device Tree node lookup

commit d1cc0ec3da23e44c23712579515494b374f111c9 upstream.

Fix child-node lookup during probe, which ended up searching the whole
device tree depth-first starting at the parent rather than just matching
on its children.

To make things worse, the parent mfd node was also prematurely freed,
while the child backlight node was leaked.

Cc: stable <stable@vger.kernel.org>     # 3.9
Fixes: 47ec340cb8e2 ("mfd: max8925: Support dt for backlight")
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/video/backlight/max8925_bl.c b/drivers/video/backlight/max8925_bl.c
index 7b738d6..f3aa608 100644 (file)
--- a/drivers/video/backlight/max8925_bl.c
+++ b/drivers/video/backlight/max8925_bl.c
@@ -116,7 +116,7 @@ static void max8925_backlight_dt_init(struct platform_device *pdev)
        if (!pdata)
                return;
 
-       np = of_find_node_by_name(nproot, "backlight");
+       np = of_get_child_by_name(nproot, "backlight");
        if (!np) {
                dev_err(&pdev->dev, "failed to find backlight node\n");
                return;
@@ -125,6 +125,8 @@ static void max8925_backlight_dt_init(struct platform_device *pdev)
        if (!of_property_read_u32(np, "maxim,max8925-dual-string", &val))
                pdata->dual_string = val;
 
+       of_node_put(np);
+
        pdev->dev.platform_data = pdata;
 }