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SubjectRe: [PATCH] usb: dwc3: usb/dwc3: fake dissconnect event when turn off pullup
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Hello.

On 4/27/2016 11:29 AM, changbin.du@intel.com wrote:

> From: "Du, Changbin" <changbin.du@intel.com>
>
> The dwc3 controller can't generate a disconnect event after it is
> stopped. Thus gadget dissconnect callback is not invoked when do
> soft dissconnect. Call dissconnect here to workaround this issue.

"Disconnect" everywhere.

> Note, most time we still see disconnect be called that because
> it is invoked by dwc3_gadget_reset_interrupt(). But if we
> disconnect cable once pullup disabled quickly, issue can be
> observed.
>
> Signed-off-by: Du, Changbin <changbin.du@intel.com>
> ---
> drivers/usb/dwc3/gadget.c | 33 ++++++++++++++++++++++++---------
> 1 file changed, 24 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 8e4a1b1..cd73187 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
[...]
> @@ -1575,6 +1584,21 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
> is_on = !!is_on;
>
> spin_lock_irqsave(&dwc->lock, flags);
> + /**
> + * WORKAROUND: The dwc3 controller can't generate a disconnect
> + * event after it is stopped. Thus gadget dissconnect callback
> + * is not invoked when do soft dissconnect. Call dissconnect
> + * here to workaround this issue.

"Disconnect" everywhere.

> + * Note, most time we still see disconnect be called that because

I couldn't parse that.

> + * it is invoked by dwc3_gadget_reset_interrupt(). But if we
> + * disconnect cable once pullup disabled quickly, issue can be
> + * observed.
> + */
> + if (!is_on && (dwc->gadget.speed != USB_SPEED_UNKNOWN)) {
> + dev_dbg(dwc->dev, "fake dissconnect event on pullup off\n");

Disconnect.

> + dwc3_disconnect_gadget(dwc);
> + dwc->gadget.speed = USB_SPEED_UNKNOWN;
> + }
> ret = dwc3_gadget_run_stop(dwc, is_on, false);
> spin_unlock_irqrestore(&dwc->lock, flags);
>
[...]

MBR, Sergei

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