Re: [PATCH] usb:cdns3: Fix for CV CH9 running with g_zero driver.

From: Peter Chen <peter.chen@nxp.com>
To: Pawel Laszczak <pawell@cadence.com>
Cc: "felipe.balbi@linux.intel.com" <felipe.balbi@linux.intel.com>,
	"gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>,
	"linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>,
	"rogerq@ti.com" <rogerq@ti.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"jbergsagel@ti.com" <jbergsagel@ti.com>,
	"nsekhar@ti.com" <nsekhar@ti.com>, "nm@ti.com" <nm@ti.com>,
	"sureshp@cadence.com" <sureshp@cadence.com>,
	"kurahul@cadence.com" <kurahul@cadence.com>
Subject: Re: [PATCH] usb:cdns3: Fix for CV CH9 running with g_zero driver.
Date: Tue, 8 Oct 2019 06:56:35 +0000	[thread overview]
Message-ID: <20191008065619.GE5670@b29397-desktop> (raw)
In-Reply-To: <1570430355-26118-1-git-send-email-pawell@cadence.com>

On 19-10-07 07:39:11, Pawel Laszczak wrote:
> Patch fixes issue with Halt Endnpoint Test observed

%s/Endnpoint/Endpoint

>
> during using g_zero
> driver as DUT. Bug occurred only on some testing board.

g_zero is legacy, please use configfs function source_sink or loopback
instead.

> 
> Endpoint can defer transition to Halted state if endpoint has pending
> requests.

The implementation of halt handling is a little complicated, you may
consider return -EAGAIN for functional stall through usb_ep_set_halt
from function driver if the requests are pending, it doesn't need to
defer such kinds of functional stall.

Peter
> Patch add additional condition that allows to return correct endpoint
> status during Get Endpoint Status request even if the halting endpoint
> is in progress.
> 
> Reported-by: Rahul Kumar <kurahul@cadence.com>
> Signed-off-by: Rahul Kumar <kurahul@cadence.com>
> Signed-off-by: Pawel Laszczak <pawell@cadence.com>
> Fixes: 7733f6c32e36 ("usb: cdns3: Add Cadence USB3 DRD Driver")
> ---
>  drivers/usb/cdns3/ep0.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/cdns3/ep0.c b/drivers/usb/cdns3/ep0.c
> index 44f652e8b5a2..10ae03430f34 100644
> --- a/drivers/usb/cdns3/ep0.c
> +++ b/drivers/usb/cdns3/ep0.c
> @@ -234,9 +234,11 @@ static int cdns3_req_ep0_set_address(struct cdns3_device *priv_dev,
>  static int cdns3_req_ep0_get_status(struct cdns3_device *priv_dev,
>  				    struct usb_ctrlrequest *ctrl)
>  {
> +	struct cdns3_endpoint *priv_ep;
>  	__le16 *response_pkt;
>  	u16 usb_status = 0;
>  	u32 recip;
> +	u8 index;
>  
>  	recip = ctrl->bRequestType & USB_RECIP_MASK;
>  
> @@ -262,9 +264,13 @@ static int cdns3_req_ep0_get_status(struct cdns3_device *priv_dev,
>  	case USB_RECIP_INTERFACE:
>  		return cdns3_ep0_delegate_req(priv_dev, ctrl);
>  	case USB_RECIP_ENDPOINT:
> -		/* check if endpoint is stalled */
> +		index = cdns3_ep_addr_to_index(ctrl->wIndex);
> +		priv_ep = priv_dev->eps[index];
> +
> +		/* check if endpoint is stalled or stall is pending */
>  		cdns3_select_ep(priv_dev, ctrl->wIndex);
> -		if (EP_STS_STALL(readl(&priv_dev->regs->ep_sts)))
> +		if (EP_STS_STALL(readl(&priv_dev->regs->ep_sts)) ||
> +		    (priv_ep->flags & EP_STALL_PENDING))
>  			usb_status =  BIT(USB_ENDPOINT_HALT);
>  		break;
>  	default:
> -- 
> 2.17.1
> 

-- 

Thanks,
Peter Chen