From patchwork Fri Apr 3 21:33:10 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Helen Mae Koike Fornazier X-Patchwork-Id: 11473681 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 2131D92C for ; Fri, 3 Apr 2020 21:33:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 007212078C for ; Fri, 3 Apr 2020 21:33:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728308AbgDCVdg (ORCPT ); Fri, 3 Apr 2020 17:33:36 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:60616 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727829AbgDCVdg (ORCPT ); Fri, 3 Apr 2020 17:33:36 -0400 Received: from floko.floko.floko (unknown [IPv6:2804:431:e7cc:11ff:4f80:3de:e2b2:5c1d]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: koike) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 1CDED29612D; Fri, 3 Apr 2020 22:33:30 +0100 (BST) From: Helen Koike To: linux-media@vger.kernel.org Cc: kernel@collabora.com, linux-kernel@vger.kernel.org, linux-rockchip@lists.infradead.org, hans.verkuil@cisco.com, skhan@linuxfoundation.org, niklas.soderlund@ragnatech.se, mchehab@kernel.org, Helen Koike Subject: [PATCH v2 1/3] media: v4l2-common: add helper functions to call s_stream() callbacks Date: Fri, 3 Apr 2020 18:33:10 -0300 Message-Id: <20200403213312.1863876-2-helen.koike@collabora.com> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200403213312.1863876-1-helen.koike@collabora.com> References: <20200403213312.1863876-1-helen.koike@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 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. Add stream_count on the subdevice object for simultaneous streaming from different video devices which shares subdevices. Prevent calling .s_stream(true) if it was already called previously by another stream. Prevent calling .s_stream(false) from one stream when there are still others active. If .s_stream(true) fails, call .s_stream(false) in the reverse order. Signed-off-by: Helen Koike Reported-by: kbuild test robot Reported-by: kbuild test robot --- Changes in v2: - re-write helpers to not use media walkers drivers/media/v4l2-core/v4l2-common.c | 117 ++++++++++++++++++++++++++ include/media/v4l2-common.h | 28 ++++++ include/media/v4l2-subdev.h | 2 + 3 files changed, 147 insertions(+) diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c index d0e5ebc736f9f..379d4bf4f8128 100644 --- a/drivers/media/v4l2-core/v4l2-common.c +++ b/drivers/media/v4l2-core/v4l2-common.c @@ -441,3 +441,120 @@ int v4l2_fill_pixfmt(struct v4l2_pix_format *pixfmt, u32 pixelformat, return 0; } EXPORT_SYMBOL_GPL(v4l2_fill_pixfmt); + +/* + * v4l2_pipeline_subdevs_get - Assemble a list of subdevices in a pipeline + * @subdevs: the array to be filled + * @size: the array size + * + * Walk from a video node, following link from sink to source and fill the + * array with subdevices in the path. + * + * Note: this function follows the first enabled link in a sink pad found in a + * given entity. Thus it won't work if there are entities with multiple enabled + * links to its sink pads in the topology. + * + * Return the number of subdevices filled in the array. + */ +static unsigned int v4l2_pipeline_subdevs_get(struct video_device *vdev, + struct v4l2_subdev **subdevs, + unsigned int size) +{ + struct media_entity *entity = &vdev->entity; + unsigned int idx = 0; + + while (1) { + struct media_pad *src_pad = NULL; + unsigned int i; + + /* Find remote source pad */ + for (i = 0; i < entity->num_pads; i++) { + struct media_pad *sink_pad = &entity->pads[i]; + + if (!(sink_pad->flags & MEDIA_PAD_FL_SINK)) + continue; + + src_pad = media_entity_remote_pad(sink_pad); + if (src_pad && + is_media_entity_v4l2_subdev(src_pad->entity)) + break; + } + if (i == entity->num_pads) + break; + + if (idx >= size) { + WARN_ON(1); + return 0; + } + + entity = src_pad->entity; + subdevs[idx++] = media_entity_to_v4l2_subdev(entity); + } + + return idx; +} + +__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; + unsigned int i, size; + int ret; + + mutex_lock(&mdev->graph_mutex); + + size = v4l2_pipeline_subdevs_get(vdev, subdevs, ARRAY_SIZE(subdevs)); + + for (i = 0; i < size; i++) { + sd = subdevs[i]; + if (sd->stream_count++) + continue; + 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) + goto err_stream_disable; + } + + mutex_unlock(&mdev->graph_mutex); + return 0; + +err_stream_disable: + do { + sd = subdevs[i]; + if (--sd->stream_count) + continue; + dev_dbg(mdev->dev, + "disabling stream for '%s'\n", sd->entity.name); + v4l2_subdev_call(sd, video, s_stream, false); + } while (i--); + + mutex_unlock(&mdev->graph_mutex); + return ret; +} +EXPORT_SYMBOL_GPL(v4l2_pipeline_stream_enable); + +void v4l2_pipeline_stream_disable(struct video_device *vdev) +{ + struct media_device *mdev = vdev->entity.graph_obj.mdev; + struct v4l2_subdev *subdevs[MEDIA_ENTITY_ENUM_MAX_DEPTH]; + unsigned int size; + + mutex_lock(&mdev->graph_mutex); + + size = v4l2_pipeline_subdevs_get(vdev, subdevs, ARRAY_SIZE(subdevs)); + + while (size--) { + struct v4l2_subdev *sd = subdevs[size]; + + if (--sd->stream_count) + continue; + dev_dbg(mdev->dev, + "disabling stream for '%s'\n", sd->entity.name); + v4l2_subdev_call(sd, video, s_stream, false); + } + + mutex_unlock(&mdev->graph_mutex); +} +EXPORT_SYMBOL_GPL(v4l2_pipeline_stream_disable); diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h index 150ee16ebd811..e833610b0f66d 100644 --- a/include/media/v4l2-common.h +++ b/include/media/v4l2-common.h @@ -519,6 +519,34 @@ int v4l2_fill_pixfmt(struct v4l2_pix_format *pixfmt, u32 pixelformat, int v4l2_fill_pixfmt_mp(struct v4l2_pix_format_mplane *pixfmt, u32 pixelformat, u32 width, u32 height); +/** + * 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. + * + * Calls to this function can be nested, in which case the same number of + * v4l2_pipeline_stream_disable() calls will be required to stop streaming. + * 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(true) callback in all the subdevices participating in the + * stream, i.e. following links from sink to source. + * + * Calls to this function can be nested, in which case the same number of + * v4l2_pipeline_stream_disable() calls will be required to stop streaming. + * The pipeline pointer must be identical for all nested calls to + * v4l2_pipeline_stream_enable(). + */ +void v4l2_pipeline_stream_disable(struct video_device *vdev); + static inline u64 v4l2_buffer_get_timestamp(const struct v4l2_buffer *buf) { /* diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h index a4848de598521..20f913a9f70c5 100644 --- a/include/media/v4l2-subdev.h +++ b/include/media/v4l2-subdev.h @@ -838,6 +838,7 @@ struct v4l2_subdev_platform_data { * @subdev_notifier: A sub-device notifier implicitly registered for the sub- * device using v4l2_device_register_sensor_subdev(). * @pdata: common part of subdevice platform data + * @stream_count: Stream count for the subdevice. * * Each instance of a subdev driver should create this struct, either * stand-alone or embedded in a larger struct. @@ -869,6 +870,7 @@ struct v4l2_subdev { struct v4l2_async_notifier *notifier; struct v4l2_async_notifier *subdev_notifier; struct v4l2_subdev_platform_data *pdata; + unsigned int stream_count; };