[PATCH 4.19 155/346] spi: fix resource leak for drivers without .remove callback

Greg Kroah-Hartman
2020-12-28T16:03:54Z

From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

[ Upstream commit 440408dbadfe47a615afd0a0a4a402e629be658a ]

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: 33cf00e57082 ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/spi/spi.c | 19 ++++++++++---------
1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index fbc5444bd9cbd..7dabbc82b6463 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -362,9 +362,11 @@ static int spi_drv_probe(struct device *dev)
if (ret)
return ret;

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

return ret;
}
@@ -372,9 +374,10 @@ 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;

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

return ret;
@@ -399,10 +402,8 @@ 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;
+ sdrv->driver.probe = spi_drv_probe;
+ sdrv->driver.remove = spi_drv_remove;
if (sdrv->shutdown)
sdrv->driver.shutdown = spi_drv_shutdown;
return driver_register(&sdrv->driver);
--
2.27.0