[PATCH v2 1/2] power: bq2415x_charger: Properly handle ENODEV from power_supply_get_by_phandle

From: Krzysztof Kozlowski
Date: Wed Oct 15 2014 - 10:25:43 EST

The power_supply_get_by_phandle() on error returns ENODEV or NULL.
The driver later expects obtained pointer to power supply to be
valid or NULL. If it is not NULL then it dereferences it in
bq2415x_notifier_call() which would lead to dereferencing ENODEV-value

Properly handle the power_supply_get_by_phandle() error case by
replacing error value with NULL. This indicates that usb charger
detection won't be used.

Fix also memory leak of 'name' if power_supply_get_by_phandle() fails
with NULL and probe should defer.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
Fixes: faffd234cf85 ("bq2415x_charger: Add DT support")
Cc: <stable@xxxxxxxxxxxxxxx>


Changes since v1:
1. Fix memory leak in probe defer (goto error_2) (suggested by Sebastian
2. Don't fail the probe if 'ti,usb-charger-detection' is not present.
Just print message.
drivers/power/bq2415x_charger.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/power/bq2415x_charger.c b/drivers/power/bq2415x_charger.c
index e384844a1ae1..edf945a5260f 100644
--- a/drivers/power/bq2415x_charger.c
+++ b/drivers/power/bq2415x_charger.c
@@ -1579,8 +1579,15 @@ static int bq2415x_probe(struct i2c_client *client,
if (np) {
bq->notify_psy = power_supply_get_by_phandle(np, "ti,usb-charger-detection");

- if (!bq->notify_psy)
- return -EPROBE_DEFER;
+ if (IS_ERR(bq->notify_psy)) {
+ bq->notify_psy = NULL;
+ dev_info(&client->dev,
+ "no 'ti,usb-charger-detection' property (err=%ld)\n",
+ PTR_ERR(bq->notify_psy));
+ } else if (!bq->notify_psy) {
+ ret = -EPROBE_DEFER;
+ goto error_2;
+ }
else if (pdata->notify_device)
bq->notify_psy = power_supply_get_by_name(pdata->notify_device);

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