Regression fix for omap interconnect code for deferred probe.
Without this fix we can get PM related warnings for devices that
use deferred probe. If necessary, this fix can wait for the
v4.12 merge window no problem.
ARM: OMAP2+: omap_device: Sync omap_device and pm_runtime after probe defer
Starting from commit 5de85b9d57ab ("PM / runtime: Re-init runtime PM
states at probe error and driver unbind") pm_runtime core now changes
device runtime_status back to after RPM_SUSPENDED after a probe defer.
Certain OMAP devices make use of "ti,no-idle-on-init" flag which causes
omap_device_enable to be called during the BUS_NOTIFY_ADD_DEVICE event
during probe, along with pm_runtime_set_active.
This call to pm_runtime_set_active typically will prevent a call to
pm_runtime_get in a driver probe function from re-enabling the
omap_device. However, in the case of a probe defer that happens before
the driver probe function is able to run, such as a missing pinctrl
states defer, pm_runtime_reinit will set the device as RPM_SUSPENDED and
then once driver probe is actually able to run, pm_runtime_get will see
the device as suspended and call through to the omap_device layer,
attempting to enable the already enabled omap_device and causing errors
like this:
omap-gpmc 50000000.gpmc: omap_device: omap_device_enable() called from
invalid state 1
omap-gpmc 50000000.gpmc: use pm_runtime_put_sync_suspend() in driver?
We can avoid this error by making sure the pm_runtime status of a device
matches the omap_device state before a probe attempt. By extending the
omap_device bus notifier to act on the BUS_NOTIFY_BIND_DRIVER event we
can check if a device is enabled in omap_device but with a pm_runtime
status of RPM_SUSPENDED and once again mark the device as RPM_ACTIVE to
avoid a second incorrect call to omap_device_enable.
Fixes: 5de85b9d57ab ("PM / runtime: Re-init runtime PM states at probe
error and driver unbind")
Tested-by: Franklin S Cooper Jr. <fcooper@ti.com>
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
1 file changed
