Subject: Re: [PATCH 2/3] usb: xhci: Add DbC support in xHCI driver
To: Felipe Balbi <felipe.balbi@linux.intel.com>,
        Mathias Nyman <mathias.nyman@linux.intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
References: <1500627169-27116-1-git-send-email-baolu.lu@linux.intel.com>
 <1500627169-27116-3-git-send-email-baolu.lu@linux.intel.com>
 <87pocu3wts.fsf@linux.intel.com>
Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
From: Lu Baolu <baolu.lu@linux.intel.com>
Message-ID: <5975709A.8070602@linux.intel.com>
Date: Mon, 24 Jul 2017 11:59:22 +0800
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Hi Felipe,

On 07/21/2017 06:31 PM, Felipe Balbi wrote:
> Hi,
>
> Lu Baolu <baolu.lu@linux.intel.com> writes:
>> +static void xhci_dbc_stop(struct xhci_hcd *xhci)
>> +{
>> +	struct xhci_dbc		*dbc = xhci->dbc;
>> +
>> +	WARN_ON(!dbc);
>> +
>> +	cancel_delayed_work_sync(&dbc->event_work);
>> +
>> +	if (dbc->gs_port_num != GSPORT_INVAL) {
>> +		gserial_disconnect(&dbc->gs_port);
>> +		gserial_free_line(dbc->gs_port_num);
> why are you tying host stack to the gadget framework?

XHCI debug capability is actually a debug device gadget.
The hardware and firmware do everything of gadget work
and leave the interface to xHCI for enabling/disabling and
queuing transfer requests.

u_serial.c provides a generic layer between a USB gadget
and the TTY layer. I used it to avoid duplicating code.

>
> With this, you're forcing every single PC in the world to compile the
> gadget framework, that's a bit much don't you think?
>

Yes, you are right. Is it acceptable if I move u_serial.c from
the current place to drivers/usb/common?

Best regards,
Lu Baolu