Commit 1fb7f12d authored Oct 22, 2015 by Douglas Anderson Committed by Felipe Balbi Nov 17, 2015

usb: dwc2: host: Fix remote wakeup when not in DWC2_L2



In commit 734643df ("usb: dwc2: host: add flag to reflect bus
state") we changed dwc2_port_suspend() not to set the lx_state
anymore (instead it sets the new bus_suspended variable).  This
introduced a bug where we would fail to detect device insertions if:

1. Plug empty hub into dwc2
2. Plug USB flash drive into the empty hub.
3. Wait a few seconds
4. Unplug USB flash drive
5. Less than 2 seconds after step 4, plug the USB flash drive in again.

The dwc2_hcd_rem_wakeup() function should have been changed to look at
the new bus_suspended variable.

Let's fix it.  Since commit b46146d5 ("usb: dwc2: host: resume root
hub on remote wakeup") talks about needing the root hub resumed if the
bus was suspended, we'll include it in our test.

It appears that the "port_l1_change" should only be set to 1 if we were
in DWC2_L1 (the driver currently never sets this), so we'll update the
former "else" case based on this test.

Fixes: 734643df ("usb: dwc2: host: add flag to reflect bus state")
Acked-by: John Youn <johnyoun@synopsys.com>
Tested-by: Gregory Herrero <gregory.herrero@intel.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>

parent f1659303

drivers/usb/dwc2/hcd.c

+5 −4

Original line number	Diff line number	Diff line
		@@ -324,12 +324,13 @@ void dwc2_hcd_disconnect(struct dwc2_hsotg *hsotg)
		*/
		static void dwc2_hcd_rem_wakeup(struct dwc2_hsotg *hsotg)
		{
		if (hsotg->lx_state == DWC2_L2) {
		if (hsotg->bus_suspended) {
		hsotg->flags.b.port_suspend_change = 1;
		usb_hcd_resume_root_hub(hsotg->priv);
		} else {
		hsotg->flags.b.port_l1_change = 1;
		}

		if (hsotg->lx_state == DWC2_L1)
		hsotg->flags.b.port_l1_change = 1;
		}

		/**
		@@ -1428,8 +1429,8 @@ static void dwc2_wakeup_detected(unsigned long data)
		dev_dbg(hsotg->dev, "Clear Resume: HPRT0=%0x\n",
		dwc2_readl(hsotg->regs + HPRT0));

		hsotg->bus_suspended = 0;
		dwc2_hcd_rem_wakeup(hsotg);
		hsotg->bus_suspended = 0;

		/* Change to L0 state */
		hsotg->lx_state = DWC2_L0;

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