From: Felipe Balbi <balbi@ti.com>
To: <changbin.du@intel.com>, <johnyoun@synopsys.com>
Cc: <gregkh@linuxfoundation.org>, <linux-usb@vger.kernel.org>,
<linux-kernel@vger.kernel.org>,
"Du, Changbin" <changbin.du@intel.com>
Subject: Re: [PATCH 1/2] usb: dwc2: add ep enabled flag to avoid double enable/disable
Date: Thu, 10 Dec 2015 11:26:15 -0600 [thread overview]
Message-ID: <87zixii5ag.fsf@saruman.tx.rr.com> (raw)
In-Reply-To: <1448860888-9841-2-git-send-email-changbin.du@intel.com>
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Hi,
changbin.du@intel.com writes:
> From: "Du, Changbin" <changbin.du@intel.com>
>
> Enabling a already enabled ep is illegal, because the ep may has trbs
> running. Reprogram the ep may break running transfer. So udc driver
> must avoid this happening by return an error -EBUSY. Gadget function
> driver also should avoid such things, but that is out of udc driver.
>
> Similarly, disable a disabled ep makes no sense, but no need return
> an error here.
>
> Signed-off-by: Du, Changbin <changbin.du@intel.com>
> ---
> drivers/usb/dwc2/core.h | 1 +
> drivers/usb/dwc2/gadget.c | 20 +++++++++++++++++++-
> 2 files changed, 20 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
> index a66d3cb..cf7eccd 100644
> --- a/drivers/usb/dwc2/core.h
> +++ b/drivers/usb/dwc2/core.h
> @@ -162,6 +162,7 @@ struct dwc2_hsotg_ep {
> unsigned char mc;
> unsigned char interval;
>
> + unsigned int enabled:1;
> unsigned int halted:1;
> unsigned int periodic:1;
> unsigned int isochronous:1;
> diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
> index 0abf73c..586bbcd 100644
> --- a/drivers/usb/dwc2/gadget.c
> +++ b/drivers/usb/dwc2/gadget.c
> @@ -2423,6 +2423,7 @@ void dwc2_hsotg_core_init_disconnected(struct dwc2_hsotg *hsotg,
> /* enable, but don't activate EP0in */
> dwc2_writel(dwc2_hsotg_ep0_mps(hsotg->eps_out[0]->ep.maxpacket) |
> DXEPCTL_USBACTEP, hsotg->regs + DIEPCTL0);
> + hsotg->eps_out[0]->enabled = 1;
>
> dwc2_hsotg_enqueue_setup(hsotg);
>
> @@ -2680,6 +2681,14 @@ static int dwc2_hsotg_ep_enable(struct usb_ep *ep,
> return -EINVAL;
> }
>
> + spin_lock_irqsave(&hsotg->lock, flags);
> + if (hs_ep->enabled) {
> + dev_warn(hsotg->dev, "%s: ep %s already enabled\n",
> + __func__, hs_ep->name);
this is a rather serious condition. I'd rather use dev_WARN_ONCE():
if (dev_WARN_ONCE(hsotg->dev, hs_ep->enabled,
"ep %s already enabled\n", hs_ep->name)) {
--
balbi
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next prev parent reply other threads:[~2015-12-10 17:26 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-11-30 5:21 [PATCH 0/2] Two fix for dwc2 gadget driver changbin.du
2015-11-30 5:21 ` [PATCH 1/2] usb: dwc2: add ep enabled flag to avoid double enable/disable changbin.du
2015-12-10 17:26 ` Felipe Balbi [this message]
2015-12-14 3:23 ` Du, Changbin
2015-11-30 5:21 ` [PATCH 2/2] usb: dwc2: forbid queuing request to a disabled ep changbin.du
2015-12-10 17:27 ` Felipe Balbi
2015-12-03 1:20 ` [PATCH 0/2] Two fix for dwc2 gadget driver John Youn
2015-12-03 4:23 ` Du, Changbin
2015-12-04 7:21 ` [PATCH] usb: gadget: forbid queuing request to a disabled ep changbin.du
2015-12-10 17:28 ` Felipe Balbi
2015-12-14 3:48 ` [PATCH v2] " changbin.du
2015-12-14 10:20 ` Du, Changbin
2015-12-16 16:52 ` Felipe Balbi
2015-12-17 9:35 ` Du, Changbin
2015-12-17 10:00 ` [PATCH v3] " changbin.du
2015-12-17 15:26 ` Felipe Balbi
2015-12-18 7:34 ` Du, Changbin
2015-12-18 7:36 ` [PATCH v4] " changbin.du
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