[PATCH v4] usb: host: xhci-mtk: avoid runtime suspend when removing hcd

[Macpaul Lin <macpaul.lin@mediatek.com>]

When runtime suspend was enabled, runtime suspend might happen
when xhci is removing hcd. This might cause kernel panic when hcd
has been freed but runtime pm suspend related handle need to
reference it.

Signed-off-by: Macpaul Lin <macpaul.lin@mediatek.com>
Reviewed-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Cc: stable@vger.kernel.org
---
Changes for v3:
  - Replace better sequence for disabling the pm_runtime suspend.
Changes for v4:
  - Thanks for Sergei's review, typo in commit description has been corrected.

 drivers/usb/host/xhci-mtk.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/xhci-mtk.c b/drivers/usb/host/xhci-mtk.c
index bfbdb3c..641d24e 100644
--- a/drivers/usb/host/xhci-mtk.c
+++ b/drivers/usb/host/xhci-mtk.c
@@ -587,6 +587,9 @@ static int xhci_mtk_remove(struct platform_device *dev)
 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
 	struct usb_hcd  *shared_hcd = xhci->shared_hcd;
 
+	pm_runtime_put_noidle(&dev->dev);
+	pm_runtime_disable(&dev->dev);
+
 	usb_remove_hcd(shared_hcd);
 	xhci->shared_hcd = NULL;
 	device_init_wakeup(&dev->dev, false);
@@ -597,8 +600,6 @@ static int xhci_mtk_remove(struct platform_device *dev)
 	xhci_mtk_sch_exit(mtk);
 	xhci_mtk_clks_disable(mtk);
 	xhci_mtk_ldos_disable(mtk);
-	pm_runtime_put_sync(&dev->dev);
-	pm_runtime_disable(&dev->dev);
 
 	return 0;
 }
-- 
1.7.9.5