[PATCH 4.4 34/53] Input: 88pm860x-ts - fix child-node lookup

Greg Kroah-Hartman
2018-01-22T08:43:07Z

From: Johan Hovold <johan@kernel.org>

commit 906bf7daa0618d0ef39f4872ca42218c29a3631f upstream.

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

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

Fixes: 2e57d56747e6 ("mfd: 88pm860x: Device tree support")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/input/touchscreen/88pm860x-ts.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)

--- a/drivers/input/touchscreen/88pm860x-ts.c
+++ b/drivers/input/touchscreen/88pm860x-ts.c
@@ -126,7 +126,7 @@ static int pm860x_touch_dt_init(struct p
int data, n, ret;
if (!np)
return -ENODEV;
- np = of_find_node_by_name(np, "touch");
+ np = of_get_child_by_name(np, "touch");
if (!np) {
dev_err(&pdev->dev, "Can't find touch node\n");
return -EINVAL;
@@ -144,13 +144,13 @@ static int pm860x_touch_dt_init(struct p
if (data) {
ret = pm860x_reg_write(i2c, PM8607_GPADC_MISC1, data);
if (ret < 0)
- return -EINVAL;
+ goto err_put_node;
}
/* set tsi prebias time */
if (!of_property_read_u32(np, "marvell,88pm860x-tsi-prebias", &data)) {
ret = pm860x_reg_write(i2c, PM8607_TSI_PREBIAS, data);
if (ret < 0)
- return -EINVAL;
+ goto err_put_node;
}
/* set prebias & prechg time of pen detect */
data = 0;
@@ -161,10 +161,18 @@ static int pm860x_touch_dt_init(struct p
if (data) {
ret = pm860x_reg_write(i2c, PM8607_PD_PREBIAS, data);
if (ret < 0)
- return -EINVAL;
+ goto err_put_node;
}
of_property_read_u32(np, "marvell,88pm860x-resistor-X", res_x);
+
+ of_node_put(np);
+
return 0;
+
+err_put_node:
+ of_node_put(np);
+
+ return -EINVAL;
}
#else
#define pm860x_touch_dt_init(x, y, z) (-1)