Commit 7e6fb678 authored by Hans de Goede's avatar Hans de Goede Committed by Sebastian Reichel
Browse files

power: supply: bq25890: Fix usb-notifier probe and remove races 



There are 2 races surrounding the usb-notifier:

1. The notifier, and thus usb_work, may run before the bq->charger
   power_supply class device is registered. But usb_work may call
   power_supply_changed() which relies on the psy device being registered.

2. usb_work may be pending/running at remove() time, so it needs to be
   cancelled on remove after unregistering the usb-notifier.

Fix 1. by moving usb-notifier registration to after the power_supply
registration.

Fix 2. by adding a cancel_work_sync() call directly after the usb-notifier
unregistration.

Reviewed-by: default avatarMarek Vasut <marex@denx.de>
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarSebastian Reichel <sebastian.reichel@collabora.com>
parent a7aaa800

drivers/power/supply/bq25890_charger.c

+12 −18
Original line number Diff line number Diff line
@@ -1391,40 +1391,34 @@ static int bq25890_probe(struct i2c_client *client) 
	if (ret)

		return ret;



	if (!IS_ERR_OR_NULL(bq->usb_phy)) {

		INIT_WORK(&bq->usb_work, bq25890_usb_work);

		bq->usb_nb.notifier_call = bq25890_usb_notifier;

		usb_register_notifier(bq->usb_phy, &bq->usb_nb);

	}



	ret = bq25890_power_supply_init(bq);

	if (ret < 0) {

		dev_err(dev, "Failed to register power supply\n");

		goto err_unregister_usb_notifier;

	}

	if (ret < 0)

		return dev_err_probe(dev, ret, "registering power supply\n");



	ret = devm_request_threaded_irq(dev, client->irq, NULL,

					bq25890_irq_handler_thread,

					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,

					BQ25890_IRQ_PIN, bq);

	if (ret)

		goto err_unregister_usb_notifier;



	return 0;

		return ret;



err_unregister_usb_notifier:

	if (!IS_ERR_OR_NULL(bq->usb_phy))

		usb_unregister_notifier(bq->usb_phy, &bq->usb_nb);

	if (!IS_ERR_OR_NULL(bq->usb_phy)) {

		INIT_WORK(&bq->usb_work, bq25890_usb_work);

		bq->usb_nb.notifier_call = bq25890_usb_notifier;

		usb_register_notifier(bq->usb_phy, &bq->usb_nb);

	}



	return ret;

	return 0;

}



static void bq25890_remove(struct i2c_client *client)

{

	struct bq25890_device *bq = i2c_get_clientdata(client);



	if (!IS_ERR_OR_NULL(bq->usb_phy))

	if (!IS_ERR_OR_NULL(bq->usb_phy)) {

		usb_unregister_notifier(bq->usb_phy, &bq->usb_nb);

		cancel_work_sync(&bq->usb_work);

	}



	if (!bq->skip_reset) {

		/* reset all registers to default values */