From patchwork Mon Jul 11 12:42:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Laurent Pinchart X-Patchwork-Id: 590696 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 F25ADC433EF for ; Mon, 11 Jul 2022 12:43:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230218AbiGKMne (ORCPT ); Mon, 11 Jul 2022 08:43:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42458 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231675AbiGKMnZ (ORCPT ); Mon, 11 Jul 2022 08:43:25 -0400 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 97CB860536 for ; Mon, 11 Jul 2022 05:43:24 -0700 (PDT) Received: from pendragon.lan (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id E078A87F; Mon, 11 Jul 2022 14:43:20 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1657543401; bh=jotMXSHy3q0Hj0KwIvP1tGaPsx9R35OcUNtbxnUUm2w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qsp3gi5zZqg2ZhLt6/EnT32nAvh3CsuhQQtvvwYM0QeHT5XLJJvSFEvm2Mn6Hcm2t U6Uk3bkPRJ84EXw7hDT/yI/Nv7iYQHKKLMtrj0hx7nUAqVa4sFN/U2/P/UAzqcz+Oj TtGU20B2FF+5pOQcbXtP8udy2vfUGqH+18u3kyOI= From: Laurent Pinchart To: linux-media@vger.kernel.org Cc: linux-rockchip@lists.infradead.org, Dafna Hirschfeld , Heiko Stuebner , Helen Koike , Paul Elder Subject: [PATCH v3 03/46] media: mc-entity: Add a new helper function to get a remote pad Date: Mon, 11 Jul 2022 15:42:05 +0300 Message-Id: <20220711124248.2683-4-laurent.pinchart@ideasonboard.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220711124248.2683-1-laurent.pinchart@ideasonboard.com> References: <20220711124248.2683-1-laurent.pinchart@ideasonboard.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org The media_entity_remote_pad_first() helper function returns the first remote pad it finds connected to a given pad. Beside being possibly non-deterministic (as it stops at the first enabled link), the fact that it returns the first match makes it unsuitable for drivers that need to guarantee that a single link is enabled, for instance when an entity can process data from one of multiple sources at a time. For those use cases, add a new helper function, media_entity_remote_pad_unique(), that operates on an entity and returns a remote pad, with a guarantee that only one link is enabled. To ease its use in drivers, also add an inline wrapper that locates source pads specifically. A wrapper that locates sink pads can easily be added when needed. Signed-off-by: Laurent Pinchart Acked-by: Hans Verkuil Acked-by: Sakari Ailus --- Changes since v2: - Update commit message Changes since v1: - Rename media_entity_remote_source_pad() to media_entity_remote_source_pad_unique() - Skip non-data links --- Documentation/driver-api/media/mc-core.rst | 3 +- drivers/media/mc/mc-entity.c | 40 +++++++++++++++++++ include/media/media-entity.h | 46 ++++++++++++++++++++++ 3 files changed, 88 insertions(+), 1 deletion(-) diff --git a/Documentation/driver-api/media/mc-core.rst b/Documentation/driver-api/media/mc-core.rst index 6eea6a3b6441..66801506b2dd 100644 --- a/Documentation/driver-api/media/mc-core.rst +++ b/Documentation/driver-api/media/mc-core.rst @@ -186,7 +186,8 @@ is required and the graph structure can be freed normally. Helper functions can be used to find a link between two given pads, or a pad connected to another pad through an enabled link -:c:func:`media_entity_find_link()` and :c:func:`media_pad_remote_pad_first()`. +(:c:func:`media_entity_find_link()`, :c:func:`media_pad_remote_pad_first()` and +:c:func:`media_entity_remote_source_pad_unique()`). Use count and power handling ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ diff --git a/drivers/media/mc/mc-entity.c b/drivers/media/mc/mc-entity.c index 55076fea7b58..bd7145932137 100644 --- a/drivers/media/mc/mc-entity.c +++ b/drivers/media/mc/mc-entity.c @@ -9,6 +9,7 @@ */ #include +#include #include #include #include @@ -920,6 +921,45 @@ struct media_pad *media_pad_remote_pad_first(const struct media_pad *pad) } EXPORT_SYMBOL_GPL(media_pad_remote_pad_first); +struct media_pad * +media_entity_remote_pad_unique(const struct media_entity *entity, + unsigned int type) +{ + struct media_pad *pad = NULL; + struct media_link *link; + + list_for_each_entry(link, &entity->links, list) { + struct media_pad *local_pad; + struct media_pad *remote_pad; + + if (((link->flags & MEDIA_LNK_FL_LINK_TYPE) != + MEDIA_LNK_FL_DATA_LINK) || + !(link->flags & MEDIA_LNK_FL_ENABLED)) + continue; + + if (type == MEDIA_PAD_FL_SOURCE) { + local_pad = link->sink; + remote_pad = link->source; + } else { + local_pad = link->source; + remote_pad = link->sink; + } + + if (local_pad->entity == entity) { + if (pad) + return ERR_PTR(-ENOTUNIQ); + + pad = remote_pad; + } + } + + if (!pad) + return ERR_PTR(-ENOLINK); + + return pad; +} +EXPORT_SYMBOL_GPL(media_entity_remote_pad_unique); + static void media_interface_init(struct media_device *mdev, struct media_interface *intf, u32 gobj_type, diff --git a/include/media/media-entity.h b/include/media/media-entity.h index ab84476b25c8..aecd1691b297 100644 --- a/include/media/media-entity.h +++ b/include/media/media-entity.h @@ -859,6 +859,52 @@ struct media_link *media_entity_find_link(struct media_pad *source, */ struct media_pad *media_pad_remote_pad_first(const struct media_pad *pad); +/** + * media_entity_remote_pad_unique - Find a remote pad connected to an entity + * @entity: The entity + * @type: The type of pad to find (MEDIA_PAD_FL_SINK or MEDIA_PAD_FL_SOURCE) + * + * Search for and return a remote pad of @type connected to @entity through an + * enabled link. If multiple (or no) remote pads match these criteria, an error + * is returned. + * + * The uniqueness constraint makes this helper function suitable for entities + * that support a single active source or sink at a time. + * + * Return: A pointer to the remote pad, or one of the following error pointers + * if an error occurs: + * + * * -ENOTUNIQ - Multiple links are enabled + * * -ENOLINK - No connected pad found + */ +struct media_pad * +media_entity_remote_pad_unique(const struct media_entity *entity, + unsigned int type); + +/** + * media_entity_remote_source_pad_unique - Find a remote source pad connected to + * an entity + * @entity: The entity + * + * Search for and return a remote source pad connected to @entity through an + * enabled link. If multiple (or no) remote pads match these criteria, an error + * is returned. + * + * The uniqueness constraint makes this helper function suitable for entities + * that support a single active source at a time. + * + * Return: A pointer to the remote pad, or one of the following error pointers + * if an error occurs: + * + * * -ENOTUNIQ - Multiple links are enabled + * * -ENOLINK - No connected pad found + */ +static inline struct media_pad * +media_entity_remote_source_pad_unique(const struct media_entity *entity) +{ + return media_entity_remote_pad_unique(entity, MEDIA_PAD_FL_SOURCE); +} + /** * media_entity_is_streaming - Test if an entity is part of a streaming pipeline * @entity: The entity