From: Uwe Kleine-König u.kleine-koenig@pengutronix.de
[ Upstream commit de5d7adb89367bbc87b4e5ce7afe7ae9bd86dc12 ]
Consider an amba driver with a .probe but without a .remove callback (e.g. pl061_gpio_driver). The function amba_probe() is called to bind a device and so dev_pm_domain_attach() and others are called. As there is no remove callback amba_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 the core driver callbacks and handle missing amba callbacks there. For probe refuse registration as a driver without probe doesn't make sense.
Fixes: 7cfe249475fd ("ARM: AMBA: Add pclk support to AMBA bus infrastructure") Reviewed-by: Ulf Hansson ulf.hansson@linaro.org Reviewed-by: Arnd Bergmann arnd@arndb.de Link: https://lore.kernel.org/r/20210126165835.687514-2-u.kleine-koenig@pengutroni... Signed-off-by: Uwe Kleine-König u.kleine-koenig@pengutronix.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/amba/bus.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-)
diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c index 1accc01fb0ca9..91c99cce22a4d 100644 --- a/drivers/amba/bus.c +++ b/drivers/amba/bus.c @@ -275,10 +275,11 @@ static int amba_remove(struct device *dev) { struct amba_device *pcdev = to_amba_device(dev); struct amba_driver *drv = to_amba_driver(dev->driver); - int ret; + int ret = 0;
pm_runtime_get_sync(dev); - ret = drv->remove(pcdev); + if (drv->remove) + ret = drv->remove(pcdev); pm_runtime_put_noidle(dev);
/* Undo the runtime PM settings in amba_probe() */ @@ -295,7 +296,9 @@ static int amba_remove(struct device *dev) static void amba_shutdown(struct device *dev) { struct amba_driver *drv = to_amba_driver(dev->driver); - drv->shutdown(to_amba_device(dev)); + + if (drv->shutdown) + drv->shutdown(to_amba_device(dev)); }
/** @@ -308,12 +311,13 @@ static void amba_shutdown(struct device *dev) */ int amba_driver_register(struct amba_driver *drv) { - drv->drv.bus = &amba_bustype; + if (!drv->probe) + return -EINVAL;
-#define SETFN(fn) if (drv->fn) drv->drv.fn = amba_##fn - SETFN(probe); - SETFN(remove); - SETFN(shutdown); + drv->drv.bus = &amba_bustype; + drv->drv.probe = amba_probe; + drv->drv.remove = amba_remove; + drv->drv.shutdown = amba_shutdown;
return driver_register(&drv->drv); }