From patchwork Mon Dec 19 14:43:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Scally X-Patchwork-Id: 13076636 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 F015EC4332F for ; Mon, 19 Dec 2022 14:44:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232539AbiLSOoO (ORCPT ); Mon, 19 Dec 2022 09:44:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45866 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232487AbiLSOn5 (ORCPT ); Mon, 19 Dec 2022 09:43:57 -0500 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 280851010 for ; Mon, 19 Dec 2022 06:43:45 -0800 (PST) Received: from mail.ideasonboard.com (cpc141996-chfd3-2-0-cust928.12-3.cable.virginm.net [86.13.91.161]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 868851929; Mon, 19 Dec 2022 15:43:36 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1671461016; bh=Tkx3o9NtB2AK/4w+uSCYt5hy8zBimFHdzxXGb7nskoU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pfl93Fr96D0liCZkdTbYFPh5d9kJoOCUTTGQROK9pQ6sLL9p2cdA02wULXV3/KsoQ 8nFxv66kCJzSq/OkpX35+slqjHdAWcJUWlTucfmZj+JTMj4Qr+wz7yzOfISE3SJXpr IFZ1U5ipAdSSuxsxl1gjkpMy+gMY+XDfXJboMoMQ= From: Daniel Scally To: linux-usb@vger.kernel.org Cc: laurent.pinchart@ideasonboard.com, gregkh@linuxfoundation.org, w36195@motorola.com, m.grzeschik@pengutronix.de, kieran.bingham@ideasonboard.com, torleiv@huddly.com, Daniel Scally Subject: [PATCH v2 7/7] usb: gadget: uvc: Allow creating new color matching descriptors Date: Mon, 19 Dec 2022 14:43:16 +0000 Message-Id: <20221219144316.757680-8-dan.scally@ideasonboard.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221219144316.757680-1-dan.scally@ideasonboard.com> References: <20221219144316.757680-1-dan.scally@ideasonboard.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Allow users to create new color matching descriptors in addition to the default one. These must be associated with a UVC format in order to be transmitted to the host, which is achieved by symlinking from the format to the newly created color matching descriptor - extend the uncompressed and mjpeg formats to support that linking operation. Signed-off-by: Daniel Scally --- Changes in v2: - New section of the ABI documentation - uvcg_format_allow_link() now checks to see if an existing link is already there - .allow_link() and .drop_link() track color_matching->refcnt .../ABI/testing/configfs-usb-gadget-uvc | 17 ++++ drivers/usb/gadget/function/uvc_configfs.c | 99 ++++++++++++++++++- 2 files changed, 114 insertions(+), 2 deletions(-) diff --git a/Documentation/ABI/testing/configfs-usb-gadget-uvc b/Documentation/ABI/testing/configfs-usb-gadget-uvc index 53258b7c6f2d..e7753b2cb11b 100644 --- a/Documentation/ABI/testing/configfs-usb-gadget-uvc +++ b/Documentation/ABI/testing/configfs-usb-gadget-uvc @@ -177,6 +177,23 @@ Description: Default color matching descriptors white ======================== ====================================== +What: /config/usb-gadget/gadget/functions/uvc.name/streaming/color_matching/name +Date: Dec 2022 +KernelVersion: 6.3 +Description: Additional color matching descriptors + + All attributes read/write: + + ======================== ====================================== + bMatrixCoefficients matrix used to compute luma and + chroma values from the color primaries + bTransferCharacteristics optoelectronic transfer + characteristic of the source picture, + also called the gamma function + bColorPrimaries color primaries and the reference + white + ======================== ====================================== + What: /config/usb-gadget/gadget/functions/uvc.name/streaming/mjpeg Date: Dec 2014 KernelVersion: 4.0 diff --git a/drivers/usb/gadget/function/uvc_configfs.c b/drivers/usb/gadget/function/uvc_configfs.c index ef5d75942f24..3be6ca936851 100644 --- a/drivers/usb/gadget/function/uvc_configfs.c +++ b/drivers/usb/gadget/function/uvc_configfs.c @@ -771,6 +771,77 @@ uvcg_format_get_default_color_match(struct config_item *streaming) return color_match; } +static int uvcg_format_allow_link(struct config_item *src, struct config_item *tgt) +{ + struct mutex *su_mutex = &src->ci_group->cg_subsys->su_mutex; + struct uvcg_color_matching *color_matching_desc; + struct config_item *streaming, *color_matching; + struct uvcg_format *fmt; + int ret = 0; + + mutex_lock(su_mutex); + + streaming = src->ci_parent->ci_parent; + color_matching = config_group_find_item(to_config_group(streaming), "color_matching"); + if (!color_matching || color_matching != tgt->ci_parent) { + ret = -EINVAL; + goto out_put_cm; + } + + fmt = to_uvcg_format(src); + + /* + * There's always a color matching descriptor associated with the format + * but without a symlink it should only ever be the default one. If it's + * not the default, there's already a symlink and we should bail out. + */ + color_matching_desc = uvcg_format_get_default_color_match(streaming); + if (fmt->color_matching != color_matching_desc) { + ret = -EBUSY; + goto out_put_cm; + } + + color_matching_desc->refcnt--; + + color_matching_desc = to_uvcg_color_matching(to_config_group(tgt)); + fmt->color_matching = color_matching_desc; + color_matching_desc->refcnt++; + +out_put_cm: + config_item_put(color_matching); + mutex_unlock(su_mutex); + + return ret; +} + +static void uvcg_format_drop_link(struct config_item *src, struct config_item *tgt) +{ + struct mutex *su_mutex = &src->ci_group->cg_subsys->su_mutex; + struct uvcg_color_matching *color_matching_desc; + struct config_item *streaming; + struct uvcg_format *fmt; + + mutex_lock(su_mutex); + + color_matching_desc = to_uvcg_color_matching(to_config_group(tgt)); + color_matching_desc->refcnt--; + + streaming = src->ci_parent->ci_parent; + color_matching_desc = uvcg_format_get_default_color_match(streaming); + + fmt = to_uvcg_format(src); + fmt->color_matching = color_matching_desc; + color_matching_desc->refcnt++; + + mutex_unlock(su_mutex); +} + +static struct configfs_item_operations uvcg_format_item_operations = { + .release = uvcg_config_item_release, + .allow_link = uvcg_format_allow_link, + .drop_link = uvcg_format_drop_link, +}; + static ssize_t uvcg_format_bma_controls_show(struct uvcg_format *f, char *page) { struct f_uvc_opts *opts; @@ -1571,7 +1642,7 @@ static struct configfs_attribute *uvcg_uncompressed_attrs[] = { }; static const struct config_item_type uvcg_uncompressed_type = { - .ct_item_ops = &uvcg_config_item_ops, + .ct_item_ops = &uvcg_format_item_operations, .ct_group_ops = &uvcg_uncompressed_group_ops, .ct_attrs = uvcg_uncompressed_attrs, .ct_owner = THIS_MODULE, @@ -1767,7 +1838,7 @@ static struct configfs_attribute *uvcg_mjpeg_attrs[] = { }; static const struct config_item_type uvcg_mjpeg_type = { - .ct_item_ops = &uvcg_config_item_ops, + .ct_item_ops = &uvcg_format_item_operations, .ct_group_ops = &uvcg_mjpeg_group_ops, .ct_attrs = uvcg_mjpeg_attrs, .ct_owner = THIS_MODULE, @@ -1922,6 +1993,29 @@ static const struct config_item_type uvcg_color_matching_type = { * streaming/color_matching */ +static struct config_group *uvcg_color_matching_make(struct config_group *group, + const char *name) +{ + struct uvcg_color_matching *color_match; + + color_match = kzalloc(sizeof(*color_match), GFP_KERNEL); + if (!color_match) + return ERR_PTR(-ENOMEM); + + color_match->desc.bLength = UVC_DT_COLOR_MATCHING_SIZE; + color_match->desc.bDescriptorType = USB_DT_CS_INTERFACE; + color_match->desc.bDescriptorSubType = UVC_VS_COLORFORMAT; + + config_group_init_type_name(&color_match->group, name, + &uvcg_color_matching_type); + + return &color_match->group; +} + +static struct configfs_group_operations uvcg_color_matching_grp_group_ops = { + .make_group = uvcg_color_matching_make, +}; + static int uvcg_color_matching_create_children(struct config_group *parent) { struct uvcg_color_matching *color_match; @@ -1947,6 +2041,7 @@ static int uvcg_color_matching_create_children(struct config_group *parent) static const struct uvcg_config_group_type uvcg_color_matching_grp_type = { .type = { .ct_item_ops = &uvcg_config_item_ops, + .ct_group_ops = &uvcg_color_matching_grp_group_ops, .ct_owner = THIS_MODULE, }, .name = "color_matching",