From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ming Lei Subject: Re: [PATCH v2 1/4] USB: introduce usb_device_no_sg_constraint() helper Date: Mon, 5 Aug 2013 22:33:32 +0800 Message-ID: References: <1375692423-9497-2-git-send-email-ming.lei@canonical.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Cc: "David S. Miller" , Greg Kroah-Hartman , Oliver Neukum , Sarah Sharp , netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Alan Stern Return-path: In-Reply-To: Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org On Mon, Aug 5, 2013 at 10:07 PM, Alan Stern wrote: > On Mon, 5 Aug 2013, Ming Lei wrote: > >> Some host controllers(such as xHCI) can support building >> packet from discontinuous buffers, so introduce one flag >> and helper for this kind of host controllers, then the >> feature can help some applications(such as usbnet) by >> supporting arbitrary length of sg buffers. > >> +static inline bool usb_device_no_sg_constraint(struct usb_device *udev) >> +{ >> + if (udev && udev->bus && udev->bus->no_sg_constraint) >> + return true; >> + else >> + return false; >> +} > > A more elegant implementation would be: > > return udev && udev->bus && udev->bus->no_sg_constraint; > > I doubt it will make any difference to the object code, though. Apart > from that, this looks fine. OK, this can save 3 line code, and I will take it in v3. > > Acked-by: Alan Stern Thanks for your Ack and review. Thanks, -- Ming Lei -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html