[PATCH] power: supply: cros_pchg: unregister EC notifier

[Hongyan Xu]

cros_pchg_probe() registers charger->notifier on the EC event notifier
chain. The driver has no remove hook, so the notifier can outlive the
devm-allocated charger.

Use devm_add_action_or_reset() to unregister the notifier on detach, and
fail probe if notifier registration fails.

This issue was found by a static analysis tool.

Signed-off-by: Hongyan Xu <getshell@xxxxxxxxxx>
---
 drivers/power/supply/cros_peripheral_charger.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/power/supply/cros_peripheral_charger.c b/drivers/power/supply/cros_peripheral_charger.c
index 962a6fd29..219cd13d6 100644
--- a/drivers/power/supply/cros_peripheral_charger.c
+++ b/drivers/power/supply/cros_peripheral_charger.c
@@ -259,6 +259,14 @@ static int cros_ec_notify(struct notifier_block *nb,
 	return cros_pchg_event(charger);
 }
 
+static void cros_pchg_unregister_notifier(void *data)
+{
+	struct charger_data *charger = data;
+
+	blocking_notifier_chain_unregister(&charger->ec_dev->ec_dev->event_notifier,
+					   &charger->notifier);
+}
+
 static int cros_pchg_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -346,7 +354,13 @@ static int cros_pchg_probe(struct platform_device *pdev)
 	ret = blocking_notifier_chain_register(&ec_dev->ec_dev->event_notifier,
 					       nb);
 	if (ret < 0)
-		dev_err(dev, "Failed to register notifier (err:%d)\n", ret);
+		return dev_err_probe(dev, ret,
+				     "Failed to register notifier\n");
+
+	ret = devm_add_action_or_reset(dev, cros_pchg_unregister_notifier,
+				       charger);
+	if (ret)
+		return ret;
 
 	return 0;
 }
-- 
2.50.1.windows.1