diff mbox series

[v4] usb: dwc3: gadget: Stop EP0 transfers during pullup disable

Message ID 20210823222458.3760-1-wcheng@codeaurora.org (mailing list archive)
State Superseded
Headers show
Series [v4] usb: dwc3: gadget: Stop EP0 transfers during pullup disable | expand

Commit Message

Wesley Cheng Aug. 23, 2021, 10:24 p.m. UTC
During a USB cable disconnect, or soft disconnect scenario, a pending
SETUP transaction may not be completed, leading to the following
error:

    dwc3 a600000.dwc3: timed out waiting for SETUP phase

If this occurs, then the entire pullup disable routine is skipped and
proper cleanup and halting of the controller does not complete.

Instead of returning an error (which is ignored from the UDC
perspective), allow the pullup disable routine to continue, which
will also handle disabling of EP0/1.  This will end any active
transfers as well.  Ensure to clear any delayed_status also, as the
timeout could happen within the STATUS stage.

Signed-off-by: Wesley Cheng <wcheng@codeaurora.org>
---
Changes in v4:
 - Fixed formatting and typos in commit text
 - Removed braces due to the removal of the return statement

Changes in v3:
 - Added suggestion by Thinh to change dev_err to dev_warn

Changes in v2:
 - Removed calls to dwc3_ep0_end_control_data() and just allow the ep disables
   on EP0 handle the proper ending of transfers.
 - Ensure that delayed_status is cleared, as ran into enumeration issues if the
   SETUP transaction fails on a STATUS stage.  Saw delayed_status == TRUE on the
   next connect, which blocked further SETUP transactions to be handled.

 drivers/usb/dwc3/gadget.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

Comments

Thinh Nguyen Aug. 24, 2021, 2:18 a.m. UTC | #1
Wesley Cheng wrote:
> During a USB cable disconnect, or soft disconnect scenario, a pending
> SETUP transaction may not be completed, leading to the following
> error:
> 
>     dwc3 a600000.dwc3: timed out waiting for SETUP phase
> 
> If this occurs, then the entire pullup disable routine is skipped and
> proper cleanup and halting of the controller does not complete.
> 
> Instead of returning an error (which is ignored from the UDC
> perspective), allow the pullup disable routine to continue, which
> will also handle disabling of EP0/1.  This will end any active
> transfers as well.  Ensure to clear any delayed_status also, as the
> timeout could happen within the STATUS stage.
> 
> Signed-off-by: Wesley Cheng <wcheng@codeaurora.org>
> ---
> Changes in v4:
>  - Fixed formatting and typos in commit text
>  - Removed braces due to the removal of the return statement
> 
> Changes in v3:
>  - Added suggestion by Thinh to change dev_err to dev_warn
> 
> Changes in v2:
>  - Removed calls to dwc3_ep0_end_control_data() and just allow the ep disables
>    on EP0 handle the proper ending of transfers.
>  - Ensure that delayed_status is cleared, as ran into enumeration issues if the
>    SETUP transaction fails on a STATUS stage.  Saw delayed_status == TRUE on the
>    next connect, which blocked further SETUP transactions to be handled.
> 
>  drivers/usb/dwc3/gadget.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 5d084542718d..63f6d9f2a692 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -2428,10 +2428,8 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
>  
>  		ret = wait_for_completion_timeout(&dwc->ep0_in_setup,
>  				msecs_to_jiffies(DWC3_PULL_UP_TIMEOUT));
> -		if (ret == 0) {
> -			dev_err(dwc->dev, "timed out waiting for SETUP phase\n");
> -			return -ETIMEDOUT;
> -		}
> +		if (ret == 0)
> +			dev_warn(dwc->dev, "timed out waiting for SETUP phase\n");
>  	}
>  
>  	/*
> @@ -2643,6 +2641,7 @@ static int __dwc3_gadget_start(struct dwc3 *dwc)
>  	/* begin to receive SETUP packets */
>  	dwc->ep0state = EP0_SETUP_PHASE;
>  	dwc->link_state = DWC3_LINK_STATE_SS_DIS;
> +	dwc->delayed_status = false;
>  	dwc3_ep0_out_start(dwc);
>  
>  	dwc3_gadget_enable_irq(dwc);
> 

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

Thanks,
Thinh
Felipe Balbi Aug. 24, 2021, 8:17 a.m. UTC | #2
Wesley Cheng <wcheng@codeaurora.org> writes:

> During a USB cable disconnect, or soft disconnect scenario, a pending
> SETUP transaction may not be completed, leading to the following
> error:
>
>     dwc3 a600000.dwc3: timed out waiting for SETUP phase
>
> If this occurs, then the entire pullup disable routine is skipped and
> proper cleanup and halting of the controller does not complete.
>
> Instead of returning an error (which is ignored from the UDC
> perspective), allow the pullup disable routine to continue, which
> will also handle disabling of EP0/1.  This will end any active
> transfers as well.  Ensure to clear any delayed_status also, as the
> timeout could happen within the STATUS stage.
>
> Signed-off-by: Wesley Cheng <wcheng@codeaurora.org>
> ---
> Changes in v4:
>  - Fixed formatting and typos in commit text
>  - Removed braces due to the removal of the return statement
>
> Changes in v3:
>  - Added suggestion by Thinh to change dev_err to dev_warn
>
> Changes in v2:
>  - Removed calls to dwc3_ep0_end_control_data() and just allow the ep disables
>    on EP0 handle the proper ending of transfers.
>  - Ensure that delayed_status is cleared, as ran into enumeration issues if the
>    SETUP transaction fails on a STATUS stage.  Saw delayed_status == TRUE on the
>    next connect, which blocked further SETUP transactions to be handled.
>
>  drivers/usb/dwc3/gadget.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 5d084542718d..63f6d9f2a692 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -2428,10 +2428,8 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
>  
>  		ret = wait_for_completion_timeout(&dwc->ep0_in_setup,
>  				msecs_to_jiffies(DWC3_PULL_UP_TIMEOUT));
> -		if (ret == 0) {
> -			dev_err(dwc->dev, "timed out waiting for SETUP phase\n");
> -			return -ETIMEDOUT;
> -		}
> +		if (ret == 0)
> +			dev_warn(dwc->dev, "timed out waiting for SETUP phase\n");

looks like a bug fix. Do we need to Cc stable?
diff mbox series

Patch

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 5d084542718d..63f6d9f2a692 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2428,10 +2428,8 @@  static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
 
 		ret = wait_for_completion_timeout(&dwc->ep0_in_setup,
 				msecs_to_jiffies(DWC3_PULL_UP_TIMEOUT));
-		if (ret == 0) {
-			dev_err(dwc->dev, "timed out waiting for SETUP phase\n");
-			return -ETIMEDOUT;
-		}
+		if (ret == 0)
+			dev_warn(dwc->dev, "timed out waiting for SETUP phase\n");
 	}
 
 	/*
@@ -2643,6 +2641,7 @@  static int __dwc3_gadget_start(struct dwc3 *dwc)
 	/* begin to receive SETUP packets */
 	dwc->ep0state = EP0_SETUP_PHASE;
 	dwc->link_state = DWC3_LINK_STATE_SS_DIS;
+	dwc->delayed_status = false;
 	dwc3_ep0_out_start(dwc);
 
 	dwc3_gadget_enable_irq(dwc);