[PATCH AUTOSEL 4.19 08/30] usb: dwc3: gadget: Do link recovery for SS and SSP

[Sasha Levin <sashal@kernel.org>]

From: Thinh Nguyen <Thinh.Nguyen@synopsys.com>

[ Upstream commit d0550cd20e52558ecf6847a0f96ebd5d944c17e4 ]

The controller always supports link recovery for device in SS and SSP.
Remove the speed limit check. Also, when the device is in RESUME or
RESET state, it means the controller received the resume/reset request.
The driver must send the link recovery to acknowledge the request. They
are valid states for the driver to send link recovery.

Fixes: 72246da40f37 ("usb: Introduce DesignWare USB3 DRD Driver")
Fixes: ee5cd41c9117 ("usb: dwc3: Update speed checks for SuperSpeedPlus")
Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/dwc3/gadget.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 50d2481041c85..99f6a5aa01095 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1577,7 +1577,6 @@ static int __dwc3_gadget_wakeup(struct dwc3 *dwc)
 	u32			reg;
 
 	u8			link_state;
-	u8			speed;
 
 	/*
 	 * According to the Databook Remote wakeup request should
@@ -1587,16 +1586,13 @@ static int __dwc3_gadget_wakeup(struct dwc3 *dwc)
 	 */
 	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
 
-	speed = reg & DWC3_DSTS_CONNECTSPD;
-	if ((speed == DWC3_DSTS_SUPERSPEED) ||
-	    (speed == DWC3_DSTS_SUPERSPEED_PLUS))
-		return 0;
-
 	link_state = DWC3_DSTS_USBLNKST(reg);
 
 	switch (link_state) {
+	case DWC3_LINK_STATE_RESET:
 	case DWC3_LINK_STATE_RX_DET:	/* in HS, means Early Suspend */
 	case DWC3_LINK_STATE_U3:	/* in HS, means SUSPEND */
+	case DWC3_LINK_STATE_RESUME:
 		break;
 	default:
 		return -EINVAL;
-- 
2.20.1