ARM: OMAP2+: omap_device: Sync omap_device and pm_runtime after probe defer
authorDave Gerlach <d-gerlach@ti.com>
Thu, 30 Mar 2017 19:58:18 +0000 (14:58 -0500)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 5 Jul 2017 12:40:29 +0000 (14:40 +0200)
commit07bb2c7e7ea369f03a8893e445639324726680a5
treef1b709d40fdd03e45b9bdfc65be299f61d159f98
parente57aa416ca4ce2af2570f3b776d738c04d9a8e3e
ARM: OMAP2+: omap_device: Sync omap_device and pm_runtime after probe defer

commit 04abaf07f6d5cdf22b7a478a86e706dfeeeef960 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/arm/mach-omap2/omap_device.c