power: supply: bq27xxx: Fix I2C IRQ race on remove

commit 444ff00 upstream.

devm_request_threaded_irq() requested IRQs are only free-ed after
the driver's remove function has ran. So the IRQ could trigger and
call bq27xxx_battery_update() after bq27xxx_battery_teardown() has
already run.

Switch to explicitly free-ing the IRQ in bq27xxx_battery_i2c_remove()
to fix this.

Fixes: 8807feb ("power: bq27xxx_battery: Add interrupt handling support")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/power/supply/bq27xxx_battery_i2c.c

@@ -179,7 +179,7 @@ static int bq27xxx_battery_i2c_probe(struct i2c_client *client)
 	i2c_set_clientdata(client, di);
 
 	if (client->irq) {
-		ret = devm_request_threaded_irq(&client->dev, client->irq,
+		ret = request_threaded_irq(client->irq,
 				NULL, bq27xxx_battery_irq_handler_thread,
 				IRQF_ONESHOT,
 				di->name, di);
@@ -209,6 +209,7 @@ static void bq27xxx_battery_i2c_remove(struct i2c_client *client)
 {
 	struct bq27xxx_device_info *di = i2c_get_clientdata(client);
 
+	free_irq(client->irq, di);
 	bq27xxx_battery_teardown(di);
 
 	mutex_lock(&battery_mutex);