[PATCH 3/5] usb: hub: Don't disable LPM completely if device initiated LPM fails

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Enabling device initiated USB3 link power management (LPM) may fail for
various reasons such as too long system exit latency, or link issues.

These are not good reason to disable hub initiated LPM U1/U2
states, especially as it requires sending more requests over a
possibly broken link, causing the hub work to block for even longer.

Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
---
 drivers/usb/core/hub.c | 13 ++-----------
 1 file changed, 2 insertions(+), 11 deletions(-)

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 10ef9f51fcfd..ccf21bb49038 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -4345,17 +4345,8 @@ static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
 	 * Enable device initiated U1/U2 with a SetFeature(U1/U2_ENABLE) request
 	 * if system exit latency is short enough and device is configured
 	 */
-	if (usb_device_may_initiate_lpm(udev, state)) {
-		if (usb_set_device_initiated_lpm(udev, state, true)) {
-			/*
-			 * Request to enable device initiated U1/U2 failed,
-			 * better to turn off lpm in this case.
-			 */
-			usb_set_lpm_timeout(udev, state, 0);
-			hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
-			return;
-		}
-	}
+	if (usb_device_may_initiate_lpm(udev, state))
+		usb_set_device_initiated_lpm(udev, state, true);
 
 	if (state == USB3_LPM_U1)
 		udev->usb3_lpm_u1_enabled = 1;
-- 
2.43.0





[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux