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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2BC0BC433F5 for ; Tue, 22 Mar 2022 13:24:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235512AbiCVNZ3 (ORCPT ); Tue, 22 Mar 2022 09:25:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50576 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235489AbiCVNZV (ORCPT ); Tue, 22 Mar 2022 09:25:21 -0400 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 282A31260D; Tue, 22 Mar 2022 06:23:53 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: dmitry.osipenko) with ESMTPSA id C68931F44055 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1647955432; bh=UUZgFPZsB8wcF1U1Mz8f6AVwvcWgacxvmEXGc0YZ/vY=; h=From:To:Cc:Subject:Date:From; b=WKpbgnfNeQ9DyrcI12UfHBreowSfUOHF2rQp2qynaOTsqV8ZvKeBPL9j0Ysz+dFbv ev8TnK4xQHXmzmpHUBsUjxWbNpTCBmVvtOVUd7n3vWST3woPEJH9BZ37mD1EVgnCWW TrKI6bx8XGxKhECDMzBlcCC/0mcAXlT1JIRpACiilzrQk4J35kSN+9l/xjmgVGZzLx KIcSgbmlhQ9sZQa8AgIbfhoB43BnThIKq+jgIfq5KD1FC1+uX0dDSvvkX6ccR8sT2B RszIyixlTXDl4+TGv+MhokLSm6jexnd+mCyLETAy51V3Ha5vzSXyMwyb1Bm7sPNr5d YnWDZo7NbRvbw== From: Dmitry Osipenko To: Mauro Carvalho Chehab , Tomasz Figa , Marek Szyprowski , Hans Verkuil , Nicolas Dufresne , Benjamin Gaignard , Andrzej Pietrasiewicz , Gustavo Padovan , Boris Brezillon , Daniel Almeida , Sebastian Fricke , Laura Nao Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, Dmitry Osipenko , Dmitry Osipenko Subject: [PATCH v1] media: videobuf2: Allow applications customize data offsets of capture buffers Date: Tue, 22 Mar 2022 16:23:29 +0300 Message-Id: <20220322132329.6527-1-dmitry.osipenko@collabora.com> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Use data offsets provided by applications for multi-planar capture buffers. This allows V4L to import and use dma-bufs exported by other subsystems in cases where application wants to customize data offsets of capture buffers in order to meet hardware alignment requirements of both dma-buf exporter and importer. This feature is wanted for providing a better support of media hardware found on Chromebooks. In particular display and camera ISP hardware of Rockchip and MediaTek SoCs require special handling by userspace because display h/w has specific alignment requirements that don't match default alignments expected by V4L and there is a need to customize the data offsets in case of multi-planar formats. Some drivers already have preliminary support for data offsets customization of capture buffers, like NVIDIA Tegra video decoder driver for example, and V4L allows applications to provide data offsets for multi-planar output buffers, let's support such customization for the capture buffers as well. Signed-off-by: Dmitry Osipenko --- Documentation/userspace-api/media/v4l/buffer.rst | 9 ++++++++- drivers/media/common/videobuf2/videobuf2-v4l2.c | 7 +++++++ 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/Documentation/userspace-api/media/v4l/buffer.rst b/Documentation/userspace-api/media/v4l/buffer.rst index 4638ec64db00..75b1929e2acb 100644 --- a/Documentation/userspace-api/media/v4l/buffer.rst +++ b/Documentation/userspace-api/media/v4l/buffer.rst @@ -369,13 +369,20 @@ struct v4l2_plane - ``data_offset`` - Offset in bytes to video data in the plane. Drivers must set this field when ``type`` refers to a capture stream, applications when - it refers to an output stream. + it refers to an output or capture stream. .. note:: That data_offset is included in ``bytesused``. So the size of the image in the plane is ``bytesused``-``data_offset`` at offset ``data_offset`` from the start of the plane. + + For capture planes data_offset may be specified by applications + and by drivers. Driver may override application's offset or error + out buffer if offset can't be satisfied by hardware. This allows + applications to customize data offsets of imported dma-bufs. + Handling of application's offsets is driver-dependent, application + must use the resulting buffer offset. * - __u32 - ``reserved[11]`` - Reserved for future use. Should be zeroed by drivers and diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c index 6edf4508c636..929107a431cc 100644 --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c @@ -263,6 +263,13 @@ static int vb2_fill_vb2_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b psrc->bytesused : pdst->length; pdst->data_offset = psrc->data_offset; } + } else { + for (plane = 0; plane < vb->num_planes; ++plane) { + struct vb2_plane *pdst = &planes[plane]; + struct v4l2_plane *psrc = &b->m.planes[plane]; + + pdst->data_offset = psrc->data_offset; + } } } else { /* -- 2.35.1