From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8878FC43381 for ; Sat, 2 Mar 2019 21:43:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 23D7820836 for ; Sat, 2 Mar 2019 21:43:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="MSOH1AYa" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726592AbfCBVnR (ORCPT ); Sat, 2 Mar 2019 16:43:17 -0500 Received: from perceval.ideasonboard.com ([213.167.242.64]:33978 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726529AbfCBVnR (ORCPT ); Sat, 2 Mar 2019 16:43:17 -0500 Received: from pendragon.ideasonboard.com (81-175-216-236.bb.dnainternet.fi [81.175.216.236]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id CAE5F54E; Sat, 2 Mar 2019 22:43:14 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1551562995; bh=1k55v4xuO5w3mqyAUbEEj/9On7TPFCInY9CTq+Lw8yk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=MSOH1AYaJovJdaMTBUhbJ4MsxVy3Lmm9aGegNzWe5DTe5fN7CVtVQeopvbgyysYcC stHYhRkhmrMAuFbtiNI4OYzp/H7nYd30XUfE7bzzc3a1fZ2N2pjl8FbGBfla4ijrkk MyXCSGC+GFPdlxVUgozUkDheNmS86fl+67CjOfFs= Date: Sat, 2 Mar 2019 23:43:08 +0200 From: Laurent Pinchart To: Shaobo He Cc: linux-media@vger.kernel.org Subject: Re: Question about drivers/media/usb/uvc/uvc_v4l2.c Message-ID: <20190302214308.GI4682@pendragon.ideasonboard.com> References: <8479deae-dedb-b7d2-58b7-8ff91f265eab@cs.utah.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <8479deae-dedb-b7d2-58b7-8ff91f265eab@cs.utah.edu> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Hi Shaobo, On Sat, Mar 02, 2019 at 01:22:49PM -0700, Shaobo He wrote: > Hello everyone, > > This is Shaobo from Utah again. I've been bugging the mailing list with my > patches. I have a quick question about a function in > `drivers/media/usb/uvc/uvc_v4l2.c`. In `uvc_v4l2_try_format`, can > `stream->nformats` be 0? I saw that in other files, this field could be zero > which is considered as error cases. I was wondering if it's true for this > function, too. The uvc_parse_streaming() function should answer this question :-) -- Regards, Laurent Pinchart