[RFC][PATCH 1/2] usb: dwc2: Improve gadget state disconnection handling

[RFC][PATCH 1/2] usb: dwc2: Improve gadget state disconnection handling

[John Stultz]

In the earlier commit dad3f793f20f ("usb: dwc2: Make sure we
disconnect the gadget state"), I was trying to fix up the
fact that we somehow weren't disconnecting the gadget state,
so that when the OTG port was plugged in the second time we
would get warnings about the state tracking being wrong.

The fix there was somewhat simple, as it just made sure to
call dwc2_hsotg_disconnect() before we connected things up
in OTG mode.

But in looking at a different issue I was seeing with UDC
state handling, I realized that it would be much better
to call dwc2_hsotg_disconnect when we get the state change
signal moving to host mode.

Thus, this patch removes the earlier disconnect call I added
and moves it (and the needed locking) to the host mode
transition.

Suggestions or feedback would be grealy appreciated!


Cc: Wei Xu <xuwei5@hisilicon.com>
Cc: Guodong Xu <guodong.xu@linaro.org>
Cc: Amit Pundir <amit.pundir@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: John Youn <johnyoun@synopsys.com>
Cc: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Chen Yu <chenyu56@huawei.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
 drivers/usb/dwc2/hcd.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
index 740c7e8..9fd84a9 100644
--- a/drivers/usb/dwc2/hcd.c
+++ b/drivers/usb/dwc2/hcd.c
@@ -3277,7 +3277,6 @@ static void dwc2_conn_id_status_change(struct work_struct *work)
 		dwc2_core_init(hsotg, false);
 		dwc2_enable_global_interrupts(hsotg);
 		spin_lock_irqsave(&hsotg->lock, flags);
-		dwc2_hsotg_disconnect(hsotg);
 		dwc2_hsotg_core_init_disconnected(hsotg, false);
 		spin_unlock_irqrestore(&hsotg->lock, flags);
 		dwc2_hsotg_core_connect(hsotg);
@@ -3296,8 +3295,13 @@ static void dwc2_conn_id_status_change(struct work_struct *work)
 		if (count > 250)
 			dev_err(hsotg->dev,
 				"Connection id status change timed out\n");
-		hsotg->op_state = OTG_STATE_A_HOST;
 
+		spin_lock_irqsave(&hsotg->lock, flags);
+		dwc2_hsotg_disconnect(hsotg);
+		dwc2_hsotg_core_init_disconnected(hsotg, false);
+		spin_unlock_irqrestore(&hsotg->lock, flags);
+
+		hsotg->op_state = OTG_STATE_A_HOST;
 		/* Initialize the Core for Host mode */
 		dwc2_core_init(hsotg, false);
 		dwc2_enable_global_interrupts(hsotg);
-- 
2.7.4

[RFC][PATCH 2/2] usb: dwc2: Fix UDC state tracking

[John Stultz]

It has been noticed that the dwc2 udc state reporting doesn't
seem to work (at least on HiKey boards). Where after the initial
setup, the sysfs /sys/class/udc/f72c0000.usb/state file would
report "configured" no matter the state of the OTG port.

This patch adds a call so that we report to the UDC layer when
the gadget device is disconnected.

Feedback or suggestions would be greatly appreciated!

Cc: Wei Xu <xuwei5@hisilicon.com>
Cc: Guodong Xu <guodong.xu@linaro.org>
Cc: Amit Pundir <amit.pundir@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: John Youn <johnyoun@synopsys.com>
Cc: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Chen Yu <chenyu56@huawei.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
 drivers/usb/dwc2/gadget.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index c4066cd..e6f2cd8 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -3202,6 +3202,8 @@ void dwc2_hsotg_disconnect(struct dwc2_hsotg *hsotg)
 
 	call_gadget(hsotg, disconnect);
 	hsotg->lx_state = DWC2_L3;
+
+	usb_gadget_set_state(&hsotg->gadget, USB_STATE_NOTATTACHED);
 }
 
 /**
-- 
2.7.4