From patchwork Fri May 22 07:55:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dafna Hirschfeld X-Patchwork-Id: 11564903 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 B23FB60D for ; Fri, 22 May 2020 07:56:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A5CDE2085B for ; Fri, 22 May 2020 07:56:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728648AbgEVH4L (ORCPT ); Fri, 22 May 2020 03:56:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49132 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728152AbgEVH4K (ORCPT ); Fri, 22 May 2020 03:56:10 -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 1A352C061A0E for ; Fri, 22 May 2020 00:56:10 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: dafna) with ESMTPSA id 0A09E2A354C From: Dafna Hirschfeld To: linux-media@vger.kernel.org, laurent.pinchart@ideasonboard.com Cc: dafna.hirschfeld@collabora.com, helen.koike@collabora.com, ezequiel@collabora.com, hverkuil@xs4all.nl, kernel@collabora.com, dafna3@gmail.com, sakari.ailus@linux.intel.com, linux-rockchip@lists.infradead.org, mchehab@kernel.org, tfiga@chromium.org, skhan@linuxfoundation.org, niklas.soderlund@ragnatech.se--annotate Subject: [PATCH v4 2/5] media: v4l2-common: add helper functions to call s_stream() callbacks Date: Fri, 22 May 2020 09:55:19 +0200 Message-Id: <20200522075522.6190-3-dafna.hirschfeld@collabora.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200522075522.6190-1-dafna.hirschfeld@collabora.com> References: <20200522075522.6190-1-dafna.hirschfeld@collabora.com> Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org From: Helen Koike Add v4l2_pipeline_stream_{enable,disable} helper functions to iterate through the subdevices in a given stream (i.e following links from sink to source) and call .s_stream() callback. If .s_stream(true) fails, call .s_stream(false) in the reverse order. Signed-off-by: Helen Koike Signed-off-by: Dafna Hirschfeld --- drivers/media/v4l2-core/v4l2-common.c | 99 +++++++++++++++++++++++++++ include/media/v4l2-common.h | 39 +++++++++++ 2 files changed, 138 insertions(+) diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c index 9e8eb45a5b03..734db2bf5ca9 100644 --- a/drivers/media/v4l2-core/v4l2-common.c +++ b/drivers/media/v4l2-core/v4l2-common.c @@ -442,3 +442,102 @@ int v4l2_fill_pixfmt(struct v4l2_pix_format *pixfmt, u32 pixelformat, return 0; } EXPORT_SYMBOL_GPL(v4l2_fill_pixfmt); + +#if defined(CONFIG_MEDIA_CONTROLLER) + +/* + * v4l2_pipeline_subdevs_get - Assemble a list of subdevices in a pipeline + * @subdevs: the array to be filled. + * @max_size: max number of elements that can fit in subdevs array. + * + * Walk from a video node, following links from sink to source and fill the + * array with subdevices in the path. + * The walker performs a depth-first traversal, which means that, in a topology + * sd1->sd2->sd3->vdev, sd1 will be the first element placed in the array. + * + * Return the number of subdevices filled in the array. + */ +static int v4l2_pipeline_subdevs_get(struct video_device *vdev, + struct v4l2_subdev **subdevs, + unsigned int max_size) +{ + struct media_entity *entity = &vdev->entity; + struct media_device *mdev = entity->graph_obj.mdev; + struct media_graph graph; + int idx = 0; + int ret; + + ret = media_graph_walk_init(&graph, mdev); + if (ret) + return ret; + + media_graph_walk_start(&graph, entity); + + while ((entity = media_graph_walk_next_stream(&graph))) { + if (!is_media_entity_v4l2_subdev(entity)) + continue; + if (WARN_ON(idx >= max_size)) + return -EINVAL; + subdevs[idx++] = media_entity_to_v4l2_subdev(entity); + } + + media_graph_walk_cleanup(&graph); + + return idx; +} + +static void v4l2_subdevs_stream_disable(struct v4l2_subdev **subdevs, int size) +{ + int i; + + for (i = 0; i < size; i++) { + struct v4l2_subdev *sd = subdevs[i]; + + dev_dbg(sd->dev, + "disabling stream for '%s'\n", sd->entity.name); + v4l2_subdev_call(sd, video, s_stream, false); + } +} + +__must_check int v4l2_pipeline_stream_enable(struct video_device *vdev) +{ + struct media_device *mdev = vdev->entity.graph_obj.mdev; + struct v4l2_subdev *subdevs[MEDIA_ENTITY_ENUM_MAX_DEPTH]; + struct v4l2_subdev *sd; + int i, size, ret; + + size = v4l2_pipeline_subdevs_get(vdev, subdevs, ARRAY_SIZE(subdevs)); + if (size <= 0) + return size; + + /* Call s_stream() in reverse order to enable sensors last */ + for (i = size - 1; i >= 0; i--) { + sd = subdevs[i]; + dev_dbg(mdev->dev, + "enabling stream for '%s'\n", sd->entity.name); + ret = v4l2_subdev_call(sd, video, s_stream, true); + if (ret && ret != -ENOIOCTLCMD) { + v4l2_subdevs_stream_disable(subdevs + i + 1, + size - i - 1); + return ret; + } + } + return 0; +} +EXPORT_SYMBOL_GPL(v4l2_pipeline_stream_enable); + +int v4l2_pipeline_stream_disable(struct video_device *vdev) +{ + struct v4l2_subdev *subdevs[MEDIA_ENTITY_ENUM_MAX_DEPTH]; + int size; + + size = v4l2_pipeline_subdevs_get(vdev, subdevs, ARRAY_SIZE(subdevs)); + if (size < 0) + return size; + + v4l2_subdevs_stream_disable(subdevs, size); + return 0; +} +EXPORT_SYMBOL_GPL(v4l2_pipeline_stream_disable); + +#endif /* CONFIG_MEDIA_CONTROLLER */ diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h index 150ee16ebd81..a278bcf3c5bc 100644 --- a/include/media/v4l2-common.h +++ b/include/media/v4l2-common.h @@ -539,4 +539,43 @@ static inline void v4l2_buffer_set_timestamp(struct v4l2_buffer *buf, buf->timestamp.tv_usec = ts.tv_nsec / NSEC_PER_USEC; } +#if defined(CONFIG_MEDIA_CONTROLLER) + +/** + * v4l2_pipeline_stream_enable - Call .s_stream(true) callbacks in the stream + * @vdev: Starting video device. + * + * Call .s_stream(true) callback in all the subdevices participating in the + * stream, i.e. following links from sink to source. + * + * .s_stream(true) is also called from sink to source, i.e. in a topology + * sd1->sd2->sd3->vdev, .s_stream(true) of sd3 is called first. + * + * Calls to this function can be nested, in which case the same number of + * v4l2_pipeline_stream_disable() calls will be required to disable streaming + * through subdevices in the pipeline. + * The pipeline pointer must be identical for all nested calls to + * v4l2_pipeline_stream_enable(). + */ +__must_check int v4l2_pipeline_stream_enable(struct video_device *vdev); + +/** + * v4l2_pipeline_stream_disable - Call .s_stream(false) callbacks in the stream + * @vdev: Starting video device. + * + * Call .s_stream(false) callback in all the subdevices participating in the + * stream, i.e. following links from sink to source. + * + * s_stream(false) is called in a reverse order from + * v4l2_pipeline_stream_enable(), i.e. in a topology sd1->sd2->sd3->vdev, + * .s_stream(false) of sd1 is called first. + * + * If multiple calls to v4l2_pipeline_stream_enable() have been made, the same + * number of calls to this function are required to disable streaming through + * subdevices in the pipeline. + */ +int v4l2_pipeline_stream_disable(struct video_device *vdev); + +#endif /* CONFIG_MEDIA_CONTROLLER */ + #endif /* V4L2_COMMON_H_ */