[PATCH] net: fec: fix runtime PM when probing MII bus

[Lucas Stach <l.stach@pengutronix.de>]

In the case where there is no "mdio" bus specified in the devicetree a plain
mdiobus_register() will be called, which tries to probe the connected PHY
by doing mdio_read() on the bus.
Since 6c3e921b18ed (net: fec: Ensure clocks are enabled while using mdio bus)
this needs runtime PM to be available, but as RPM is only later set up in the
FEC probe function those calls will fail, which in turn prevents the FEC
driver to be registered successfully.

Fix this by moving the RPM setup calls before the MII bus probing.

Also move autosuspend init calls before runtime_pm_enable() so that the RPM
callbacks aren't invoked several times during the probe function.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
---
The offending commit got in with v4.2-rc3, so this should be applied as
a fix for 4.2.
---
 drivers/net/ethernet/freescale/fec_main.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index 42e20e5385ac..349365d85b92 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -3431,6 +3431,11 @@ fec_probe(struct platform_device *pdev)
 		fep->reg_phy = NULL;
 	}
 
+	pm_runtime_set_autosuspend_delay(&pdev->dev, FEC_MDIO_PM_TIMEOUT);
+	pm_runtime_use_autosuspend(&pdev->dev);
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
 	fec_reset_phy(pdev);
 
 	if (fep->bufdesc_ex)
@@ -3465,8 +3470,6 @@ fec_probe(struct platform_device *pdev)
 	netif_carrier_off(ndev);
 	fec_enet_clk_enable(ndev, false);
 	pinctrl_pm_select_sleep_state(&pdev->dev);
-	pm_runtime_set_active(&pdev->dev);
-	pm_runtime_enable(&pdev->dev);
 
 	ret = register_netdev(ndev);
 	if (ret)
@@ -3481,8 +3484,6 @@ fec_probe(struct platform_device *pdev)
 	fep->rx_copybreak = COPYBREAK_DEFAULT;
 	INIT_WORK(&fep->tx_timeout_work, fec_enet_timeout_work);
 
-	pm_runtime_set_autosuspend_delay(&pdev->dev, FEC_MDIO_PM_TIMEOUT);
-	pm_runtime_use_autosuspend(&pdev->dev);
 	pm_runtime_mark_last_busy(&pdev->dev);
 	pm_runtime_put_autosuspend(&pdev->dev);
 
-- 
2.1.4