* Dave Gerlach <d-gerlach@xxxxxx> [170330 13:01]:
> 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.
>
> Tested-by: Franklin S Cooper Jr. <fcooper@xxxxxx>
> Signed-off-by: Dave Gerlach <d-gerlach@xxxxxx>
Applying into omap-for-v4.11/fixes thanks. Will let this one sit
in Linux next for a while.
Regards,
Tony
> ---
> arch/arm/mach-omap2/omap_device.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/arch/arm/mach-omap2/omap_device.c b/arch/arm/mach-omap2/omap_device.c
> index e920dd83e443..f989145480c8 100644
> --- a/arch/arm/mach-omap2/omap_device.c
> +++ b/arch/arm/mach-omap2/omap_device.c
> @@ -222,6 +222,14 @@ static int _omap_device_notifier_call(struct notifier_block *nb,
> dev_err(dev, "failed to idle\n");
> }
> break;
> + case BUS_NOTIFY_BIND_DRIVER:
> + od = to_omap_device(pdev);
> + if (od && (od->_state == OMAP_DEVICE_STATE_ENABLED) &&
> + pm_runtime_status_suspended(dev)) {
> + od->_driver_status = BUS_NOTIFY_BIND_DRIVER;
> + pm_runtime_set_active(dev);
> + }
> + break;
> case BUS_NOTIFY_ADD_DEVICE:
> if (pdev->dev.of_node)
> omap_device_build_from_dt(pdev);
> --
> 2.11.0
>
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