usb: xhci: plat: Enable runtime PM

This series enables runtime PM and asynchronous resume/suspend support for xhci-plat devices.

Changes since v1:
- Added Signed-off-by: Robert Foss <[email protected]>
- Added proper metadata tags to series

Changes since v2:
- Added missing changelog to cover-letter
- Added error checking to pm_runtime_get_sync() calls

Changes since v3:
- Decrement usage_counter for failed pm_runtime_get*() calls

Changes since v4:
- Added missing brackets

Changes since v5:
- Switched out atomic_dec() calls with pm_runtime_put() calls

Changes since v6:
- Rebased on v4.10-rc3
- Dropped "usb: xhci: plat: Enable async suspend/resume" since it is superseded by
https://lkml.org/lkml/2016/12/13/32

Andrew Bresticker (1):
usb: xhci: plat: Enable async suspend/resume

 drivers/usb/host/xhci-plat.c | 1 +
 1 file changed, 1 insertion(+)

2.11.0.453.g787f75f05

From: Andrew Bresticker <[email protected]>

USB host controllers can take a significant amount of time to suspend and resume, adding several hundred miliseconds to the kernel resume time. Since the XHCI controller has no outside dependencies (other than clocks, which are suspended late/resumed early), allow it to suspend and resume asynchronously.

---
 drivers/usb/host/xhci-plat.c | 1 +
 1 file changed, 1 insertion(+)

index 3cf8e120c620..4d6741a0d8f8 100644
@@ -257,6 +257,7 @@ static int xhci_plat_probe(struct platform_device *pdev)
 
 	pm_runtime_set_active(&pdev->dev);
 	pm_runtime_enable(&pdev->dev);
+	device_enable_async_suspend(&pdev->dev);
 
 	return 0;
 

2.11.0.453.g787f75f05