From patchwork Thu Dec 5 14:24:40 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ezequiel Garcia X-Patchwork-Id: 11274857 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A80A917EF for ; Thu, 5 Dec 2019 14:25:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 906732464D for ; Thu, 5 Dec 2019 14:25:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729731AbfLEOZX (ORCPT ); Thu, 5 Dec 2019 09:25:23 -0500 Received: from bhuna.collabora.co.uk ([46.235.227.227]:49402 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729717AbfLEOZU (ORCPT ); Thu, 5 Dec 2019 09:25:20 -0500 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: ezequiel) with ESMTPSA id B8D84292248 From: Ezequiel Garcia To: linux-media@vger.kernel.org Cc: kernel@collabora.com, Tomasz Figa , linux-rockchip@lists.infradead.org, Heiko Stuebner , Jonas Karlman , Philipp Zabel , Boris Brezillon , Chris Healy , linux-kernel@vger.kernel.org, Ezequiel Garcia Subject: [PATCH v4 1/4] media: vidioc-enum-fmt.rst: clarify format preference Date: Thu, 5 Dec 2019 11:24:40 -0300 Message-Id: <20191205142443.1298-2-ezequiel@collabora.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20191205142443.1298-1-ezequiel@collabora.com> References: <20191205142443.1298-1-ezequiel@collabora.com> MIME-Version: 1.0 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org It has been decided to use the ENUM_FMT index value as a hint for driver preference. This is defined purposedly in a very liberal way, letting drivers define what "preference" means. For instance, the Hantro VPU driver indicates additional processing to output a given format, and thus implicates more CPU usage, which is enumerated after native (non-processed) formats. Signed-off-by: Ezequiel Garcia Reviewed-by: Boris Brezillon --- Documentation/media/uapi/v4l/vidioc-enum-fmt.rst | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst b/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst index 399ef1062bac..8ca6ab701e4a 100644 --- a/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst +++ b/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst @@ -44,7 +44,9 @@ To enumerate image formats applications initialize the ``type`` and the :ref:`VIDIOC_ENUM_FMT` ioctl with a pointer to this structure. Drivers fill the rest of the structure or return an ``EINVAL`` error code. All formats are enumerable by beginning at index zero and incrementing by -one until ``EINVAL`` is returned. +one until ``EINVAL`` is returned. If applicable, drivers shall return +formats in preference order, where preferred formats are returned before +(that is, with lower ``index`` value) less-preferred formats. .. note::