[PATCH] usb: dwc2: resume root hub to handle disconnect of device

William Wu william.wu at rock-chips.com
Fri May 26 20:23:36 PDT 2017


When handle disconnect of the hcd during bus_suspend, hcd
needs to resume its root hub, otherwise the root hub will
not disconnect the existing devices under its port.

This issue always happens when connecting with usb devices
which support auto-suspend function (e.g. usb hub).

Signed-off-by: William Wu <william.wu at rock-chips.com>
---
 drivers/usb/dwc2/hcd.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
index 740c7e8..cc84f97 100644
--- a/drivers/usb/dwc2/hcd.c
+++ b/drivers/usb/dwc2/hcd.c
@@ -1975,11 +1975,13 @@ void dwc2_hcd_disconnect(struct dwc2_hsotg *hsotg, bool force)
 	 * Without the extra check here we will end calling disconnect
 	 * and won't get any future interrupts to handle the connect.
 	 */
-	if (!force) {
-		hprt0 = dwc2_readl(hsotg->regs + HPRT0);
-		if (!(hprt0 & HPRT0_CONNDET) && (hprt0 & HPRT0_CONNSTS))
-			dwc2_hcd_connect(hsotg);
-	}
+	hprt0 = dwc2_readl(hsotg->regs + HPRT0);
+
+	if (!force && !(hprt0 & HPRT0_CONNDET) &&
+	    (hprt0 & HPRT0_CONNSTS))
+		dwc2_hcd_connect(hsotg);
+	else if (hsotg->lx_state != DWC2_L0)
+		usb_hcd_resume_root_hub(hsotg->priv);
 }
 
 /**
-- 
2.0.0





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