From patchwork Wed Sep 12 21:29:41 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sakari Ailus X-Patchwork-Id: 10598371 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4121114DB for ; Wed, 12 Sep 2018 21:30:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 318752ACAD for ; Wed, 12 Sep 2018 21:30:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 262C02ACAC; Wed, 12 Sep 2018 21:30:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id A9DAF2ACAD for ; Wed, 12 Sep 2018 21:30:10 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C2C746E4E1; Wed, 12 Sep 2018 21:29:59 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from hillosipuli.retiisi.org.uk (hillosipuli.retiisi.org.uk [IPv6:2001:1bc8:1a6:d3d5::81:2]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4FCE16E4FF for ; Wed, 12 Sep 2018 21:29:51 +0000 (UTC) Received: from lanttu.localdomain (lanttu-e.localdomain [192.168.1.64]) by hillosipuli.retiisi.org.uk (Postfix) with ESMTP id 7D73F634CA5; Thu, 13 Sep 2018 00:29:44 +0300 (EEST) From: Sakari Ailus To: linux-media@vger.kernel.org Subject: [PATCH v3 22/23] v4l: fwnode: Update V4L2 fwnode endpoint parsing documentation Date: Thu, 13 Sep 2018 00:29:41 +0300 Message-Id: <20180912212942.19641-23-sakari.ailus@linux.intel.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20180912212942.19641-1-sakari.ailus@linux.intel.com> References: <20180912212942.19641-1-sakari.ailus@linux.intel.com> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, jacopo@jmondi.org, dri-devel@lists.freedesktop.org, slongerbeam@gmail.com, niklas.soderlund@ragnatech.se MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP The semantics of v4l2_fwnode_endpoint_parse() and v4l2_fwnode_endpoint_alloc_parse() have changed slightly: they now take the bus type from the user as well as a default configuration for the bus that shall reflect the DT binding defaults. Document this. Signed-off-by: Sakari Ailus Tested-by: Steve Longerbeam --- include/media/v4l2-fwnode.h | 56 ++++++++++++++++++++++++++++++--------------- 1 file changed, 37 insertions(+), 19 deletions(-) diff --git a/include/media/v4l2-fwnode.h b/include/media/v4l2-fwnode.h index 1ea1a3ecf6d5..b4a49ca27579 100644 --- a/include/media/v4l2-fwnode.h +++ b/include/media/v4l2-fwnode.h @@ -131,21 +131,30 @@ struct v4l2_fwnode_link { * @fwnode: pointer to the endpoint's fwnode handle * @vep: pointer to the V4L2 fwnode data structure * - * All properties are optional. If none are found, we don't set any flags. This - * means the port has a static configuration and no properties have to be - * specified explicitly. If any properties that identify the bus as parallel - * are found and slave-mode isn't set, we set V4L2_MBUS_MASTER. Similarly, if - * we recognise the bus as serial CSI-2 and clock-noncontinuous isn't set, we - * set the V4L2_MBUS_CSI2_CONTINUOUS_CLOCK flag. The caller should hold a - * reference to @fwnode. - * - * The caller must set the bus_type field of @vep to zero. + * This function parses the V4L2 fwnode endpoint specific parameters from the + * firmware. The caller is responsible for assigning @vep.bus_type to a valid + * media bus type. The caller may also set the default configuration for the + * endpoint --- a configuration that shall be in line with the DT binding + * documentation. Should a device support multiple bus types, the caller may + * call this function once the correct type is found --- with a default + * configuration valid for that type. + * + * As a compatibility means guessing the bus type is also supported by setting + * @vep.bus_type to V4L2_MBUS_UNKNOWN. The caller may not provide a default + * configuration in this case as the defaults are specific to a given bus type. + * This functionality is deprecated and should not be used in new drivers and it + * is only supported for CSI-2 D-PHY, parallel and Bt.656 busses. + * + * The function does not change the V4L2 fwnode endpoint state if it fails. * * NOTE: This function does not parse properties the size of which is variable * without a low fixed limit. Please use v4l2_fwnode_endpoint_alloc_parse() in * new drivers instead. * - * Return: 0 on success or a negative error code on failure. + * Return: %0 on success or a negative error code on failure: + * %-ENOMEM on memory allocation failure + * %-EINVAL on parsing failure + * %-ENXIO on mismatching bus types */ int v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode, struct v4l2_fwnode_endpoint *vep); @@ -165,15 +174,21 @@ void v4l2_fwnode_endpoint_free(struct v4l2_fwnode_endpoint *vep); * @fwnode: pointer to the endpoint's fwnode handle * @vep: pointer to the V4L2 fwnode data structure * - * All properties are optional. If none are found, we don't set any flags. This - * means the port has a static configuration and no properties have to be - * specified explicitly. If any properties that identify the bus as parallel - * are found and slave-mode isn't set, we set V4L2_MBUS_MASTER. Similarly, if - * we recognise the bus as serial CSI-2 and clock-noncontinuous isn't set, we - * set the V4L2_MBUS_CSI2_CONTINUOUS_CLOCK flag. The caller should hold a - * reference to @fwnode. + * This function parses the V4L2 fwnode endpoint specific parameters from the + * firmware. The caller is responsible for assigning @vep.bus_type to a valid + * media bus type. The caller may also set the default configuration for the + * endpoint --- a configuration that shall be in line with the DT binding + * documentation. Should a device support multiple bus types, the caller may + * call this function once the correct type is found --- with a default + * configuration valid for that type. + * + * As a compatibility means guessing the bus type is also supported by setting + * @vep.bus_type to V4L2_MBUS_UNKNOWN. The caller may not provide a default + * configuration in this case as the defaults are specific to a given bus type. + * This functionality is deprecated and should not be used in new drivers and it + * is only supported for CSI-2 D-PHY, parallel and Bt.656 busses. * - * The caller must set the bus_type field of @vep to zero. + * The function does not change the V4L2 fwnode endpoint state if it fails. * * v4l2_fwnode_endpoint_alloc_parse() has two important differences to * v4l2_fwnode_endpoint_parse(): @@ -183,7 +198,10 @@ void v4l2_fwnode_endpoint_free(struct v4l2_fwnode_endpoint *vep); * 2. The memory it has allocated to store the variable size data must be freed * using v4l2_fwnode_endpoint_free() when no longer needed. * - * Return: 0 on success or a negative error code on failure. + * Return: %0 on success or a negative error code on failure: + * %-ENOMEM on memory allocation failure + * %-EINVAL on parsing failure + * %-ENXIO on mismatching bus types */ int v4l2_fwnode_endpoint_alloc_parse( struct fwnode_handle *fwnode, struct v4l2_fwnode_endpoint *vep);