Unverified Commit 440408db authored Nov 19, 2020 by Uwe Kleine-König Committed by Mark Brown Nov 20, 2020

spi: fix resource leak for drivers without .remove callback

Consider an spi driver with a .probe but without a .remove callback (e.g.
rtc-ds1347). The function spi_drv_probe() is called to bind a device and
so dev_pm_domain_attach() is called. As there is no remove callback
spi_drv_remove() isn't called at unbind time however and so calling
dev_pm_domain_detach() is missed and the pm domain keeps active.

To fix this always use both spi_drv_probe() and spi_drv_remove() and
make them handle the respective callback not being set. This has the
side effect that for a (hypothetical) driver that has neither .probe nor
remove the clk and pm domain setup is done.

Fixes: 33cf00e5 ("spi: attach/detach SPI device to the ACPI power domain")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20201119161604.2633521-1-u.kleine-koenig@pengutronix.de

Signed-off-by: Mark Brown <broonie@kernel.org>

parent 03fc41af

drivers/spi/spi.c

+10 −9

Original line number	Diff line number	Diff line
		@@ -405,9 +405,11 @@ static int spi_drv_probe(struct device *dev)
		if (ret)
		return ret;

		if (sdrv->probe) {
		ret = sdrv->probe(spi);
		if (ret)
		dev_pm_domain_detach(dev, true);
		}

		return ret;
		}
		@@ -415,8 +417,9 @@ static int spi_drv_probe(struct device *dev)
		static int spi_drv_remove(struct device *dev)
		{
		const struct spi_driver *sdrv = to_spi_driver(dev->driver);
		int ret;
		int ret = 0;

		if (sdrv->remove)
		ret = sdrv->remove(to_spi_device(dev));
		dev_pm_domain_detach(dev, true);

		@@ -442,9 +445,7 @@ int __spi_register_driver(struct module owner, struct spi_driver sdrv)
		{
		sdrv->driver.owner = owner;
		sdrv->driver.bus = &spi_bus_type;
		if (sdrv->probe)
		sdrv->driver.probe = spi_drv_probe;
		if (sdrv->remove)
		sdrv->driver.remove = spi_drv_remove;
		if (sdrv->shutdown)
		sdrv->driver.shutdown = spi_drv_shutdown;