usb: hub: Fix flushing and scheduling of delayed work that tunes runtime pm

JIRA: https://issues.redhat.com/browse/RHEL-102858

commit a49e1e2
Author: Mathias Nyman <mathias.nyman@linux.intel.com>
Date: Thu, 26 Jun 2025 16:01:02 +0300

  Delayed work to prevent USB3 hubs from runtime-suspending immediately
  after resume was added in commit 8f5b7e2 ("usb: hub: fix detection
  of high tier USB3 devices behind suspended hubs").

  This delayed work needs be flushed if system suspends, or hub needs to
  be quiesced for other reasons right after resume. Not flushing it
  triggered issues on QC SC8280XP CRD board during suspend/resume testing.

  Fix it by flushing the delayed resume work in hub_quiesce()

  The delayed work item that allow hub runtime suspend is also scheduled
  just before calling autopm get. Alan pointed out there is a small risk
  that work is run before autopm get, which would call autopm put before
  get, and mess up the runtime pm usage order.
  Swap the order of work sheduling and calling autopm get to solve this.

  Cc: stable <stable@kernel.org>
  Fixes: 8f5b7e2 ("usb: hub: fix detection of high tier USB3 devices behind suspended hubs")
  Reported-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
  Closes: https://lore.kernel.org/linux-usb/acaaa928-832c-48ca-b0ea-d202d5cd3d6c@oss.qualcomm.com
  Reported-by: Alan Stern <stern@rowland.harvard.edu>
  Closes: https://lore.kernel.org/linux-usb/c73fbead-66d7-497a-8fa1-75ea4761090a@rowland.harvard.edu
  Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
  Link: https://lore.kernel.org/r/20250626130102.3639861-2-mathias.nyman@linux.intel.com
  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Desnes Nunes <desnesn@redhat.com>

Author: Desnes Nunes

drivers/usb/core/hub.c

@@ -1359,11 +1359,12 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
 
 	if (type == HUB_RESUME && hub_is_superspeed(hub->hdev)) {
 		/* give usb3 downstream links training time after hub resume */
+		usb_autopm_get_interface_no_resume(
+			to_usb_interface(hub->intfdev));
+
 		INIT_DELAYED_WORK(&hub->init_work, hub_post_resume);
 		queue_delayed_work(system_power_efficient_wq, &hub->init_work,
 				   msecs_to_jiffies(USB_SS_PORT_U0_WAKE_TIME));
-		usb_autopm_get_interface_no_resume(
-			to_usb_interface(hub->intfdev));
 		return;
 	}
 
@@ -1417,6 +1418,7 @@ static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
 
 	/* Stop hub_wq and related activity */
 	timer_delete_sync(&hub->irq_urb_retry);
+	flush_delayed_work(&hub->init_work);
 	usb_kill_urb(hub->urb);
 	if (hub->has_indicators)
 		cancel_delayed_work_sync(&hub->leds);