From c8540870af4ce6ddeb27a7bb5498b75fb29b643c Mon Sep 17 00:00:00 2001

From: Roger Quadros <rogerq@kernel.org>

Date: Wed, 3 May 2023 14:00:48 +0300

Subject: [PATCH] usb: dwc3: gadget: Improve dwc3_gadget_suspend() and

 dwc3_gadget_resume()

Git-commit: c8540870af4ce6ddeb27a7bb5498b75fb29b643c

References: git-fixes

Patch-mainline: v6.4-rc3

Prevent -ETIMEDOUT error on .suspend().

e.g. If gadget driver is loaded and we are connected to a USB host,

all transfers must be stopped before stopping the controller else

we will not get a clean stop i.e. dwc3_gadget_run_stop() will take

several seconds to complete and will return -ETIMEDOUT.

Handle error cases properly in dwc3_gadget_suspend().

Simplify dwc3_gadget_resume() by using the introduced helper function.

Fixes: 9f8a67b65a49 ("usb: dwc3: gadget: fix gadget suspend/resume")

Cc: stable@vger.kernel.org

Suggested-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>

Signed-off-by: Roger Quadros <rogerq@kernel.org>

Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>

Link: https://lore.kernel.org/r/20230503110048.30617-1-rogerq@kernel.org

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Oliver Neukum <oneukum@suse.com>

---

 drivers/usb/dwc3/gadget.c |   50 ++++++++++++++++++++++++++++++++--------------

 1 file changed, 35 insertions(+), 15 deletions(-)

--- a/drivers/usb/dwc3/gadget.c

+++ b/drivers/usb/dwc3/gadget.c

@@ -2352,6 +2352,21 @@ static int dwc3_gadget_soft_disconnect(s

 	return dwc3_gadget_run_stop(dwc, false, false);

 }

+static int dwc3_gadget_soft_connect(struct dwc3 *dwc)

+{

+	/*

+	 * In the Synopsys DWC_usb31 1.90a programming guide section

+	 * 4.1.9, it specifies that for a reconnect after a

+	 * device-initiated disconnect requires a core soft reset

+	 * (DCTL.CSftRst) before enabling the run/stop bit.

+	 */

+	dwc3_core_soft_reset(dwc);

+

+	dwc3_event_buffers_setup(dwc);

+	__dwc3_gadget_start(dwc);

+	return dwc3_gadget_run_stop(dwc, true, false);

+}

+

 static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)

 {

 	struct dwc3		*dwc = gadget_to_dwc(g);

@@ -2388,21 +2403,11 @@ static int dwc3_gadget_pullup(struct usb

 		return 0;

 	}

-	if (!is_on) {

+	if (!is_on)

 		ret = dwc3_gadget_soft_disconnect(dwc);

-	} else {

-		/*

-		 * In the Synopsys DWC_usb31 1.90a programming guide section

-		 * 4.1.9, it specifies that for a reconnect after a

-		 * device-initiated disconnect requires a core soft reset

-		 * (DCTL.CSftRst) before enabling the run/stop bit.

-		 */

-		dwc3_core_soft_reset(dwc);

+	else

+		ret = dwc3_gadget_soft_connect(dwc);

-		dwc3_event_buffers_setup(dwc);

-		__dwc3_gadget_start(dwc);

-		ret = dwc3_gadget_run_stop(dwc, true, false);

-	}

 	pm_runtime_put(dwc->dev);

@@ -4271,14 +4276,29 @@ void dwc3_gadget_exit(struct dwc3 *dwc)

 int dwc3_gadget_suspend(struct dwc3 *dwc)

 {

+	int ret;

+

 	if (!dwc->gadget_driver)

 		return 0;

-	dwc3_gadget_run_stop(dwc, false, false);

+	ret = dwc3_gadget_soft_disconnect(dwc);

+	if (ret)

+		goto err;

+

 	dwc3_disconnect_gadget(dwc);

-	__dwc3_gadget_stop(dwc);

 	return 0;

+

+err:

+	/*

+	 * Attempt to reset the controller's state. Likely no

+	 * communication can be established until the host

+	 * performs a port reset.

+	 */

+	if (dwc->softconnect)

+		dwc3_gadget_soft_connect(dwc);

+

+	return ret;

 }

 int dwc3_gadget_resume(struct dwc3 *dwc)