From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7FB981922E6; Thu, 29 Aug 2024 15:50:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724946616; cv=none; b=g/l4RYu6441GtQ9E/zOvsuY+EIF0P6WjSQgi0pHWh7g3PoAOy0bsWSCEoQ7vHPKuvJPqyGuUbpt2VvqhtxC5EiydgbpxoogsD0ILlSp/tjz8d/GLNZMzPeqDk1r97mrbmxg5iVb8BPAilYfFGYyXlXSGRtgeKHv+OfmyW+KgBwo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724946616; c=relaxed/simple; bh=KccHSL6fnfRyNdZ90h1lu3IkO6/vw/VRe94K7w5iAy4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=OLRj3L+klEIlWpWZgxcoqZR+QLCfH03cNYfZg5lrLENcW6/jDxmsrUbd04XA3lXLWEGBQYJDnNDtLPeZFltUh4CZp/Ru6raI4y+O5/TIYq0LcaQAhjsByhroEgezhrOCpotto7D/9zMj938AXZHknu2VLVTd5m34MTVzjwdWWj8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WIDYYNtx; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="WIDYYNtx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CADD2C4CEC1; Thu, 29 Aug 2024 15:50:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1724946616; bh=KccHSL6fnfRyNdZ90h1lu3IkO6/vw/VRe94K7w5iAy4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=WIDYYNtxl0pvt7YlIt1csogI9T2a15xk1/T4FECWLIFS9jXTqScuicaXrxQ/2b8Gh qsK2yQRiErDgH9jEeSwnKvx2fWa5S10GuWUcyUaPJmocSQUu3N8UH/zXmZqsikYedH WfwZMoOpUe/kVao3rxXw3KbmgVpfef7CVVDCXh47RDPsrAmZy5S4UunyrPI+PFdhQc iaEtzw6QhCrqPYWA7OescM0zVcH1JNLwEfI6os+SWN9JskUmguFMTOpmVVHIEREJ27 et59OKxRrNSj+Hq3jrAB3UIhDPnWiW2bKaXH4JtpRN2qet+nJCRlKIReqetlLGq/uQ niInKANx9CERA== Date: Thu, 29 Aug 2024 10:50:14 -0500 From: Rob Herring To: Kuninori Morimoto Cc: Daniel Vetter , David Airlie , Helge Deller , Jaroslav Kysela , Laurent Pinchart , Liam Girdwood , Maarten Lankhorst , Mark Brown , Mauro Carvalho Chehab , Maxime Ripard , Michal Simek , Saravana Kannan , Takashi Iwai , Thomas Zimmermann , Tomi Valkeinen , devicetree@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-fbdev@vger.kernel.org, linux-media@vger.kernel.org, linux-omap@vger.kernel.org, linux-sound@vger.kernel.org, Sakari Ailus Subject: Re: [PATCH v4 1/9] of: property: add of_graph_get_next_port() Message-ID: <20240829155014.GE465065-robh@kernel.org> References: <87bk1d2pvt.wl-kuninori.morimoto.gx@renesas.com> <87a5gx2pva.wl-kuninori.morimoto.gx@renesas.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87a5gx2pva.wl-kuninori.morimoto.gx@renesas.com> On Wed, Aug 28, 2024 at 05:11:37AM +0000, Kuninori Morimoto wrote: > We have endpoint base functions > - of_graph_get_next_device_endpoint() > - of_graph_get_device_endpoint_count() > - for_each_of_graph_device_endpoint() > > Here, for_each_of_graph_device_endpoint() loop finds each endpoints > > ports { > port@0 { > (1) endpoint {...}; > }; > port@1 { > (2) endpoint {...}; > }; > ... > }; > > In above case, it finds endpoint as (1) -> (2) -> ... > > Basically, user/driver knows which port is used for what, but not in > all cases. For example on flexible/generic driver case, how many ports > are used is not fixed. > > For example Sound Generic Card driver which is used from many venders > can't know how many ports are used. Because the driver is very > flexible/generic, it is impossible to know how many ports are used, > it depends on each vender SoC and/or its used board. > > And more, the port can have multi endpoints. For example Generic Sound > Card case, it supports many type of connection between CPU / Codec, and > some of them uses multi endpoint in one port. > Then, Generic Sound Card want to handle each connection via "port" > instead of "endpoint". > But, it is very difficult to handle each "port" via existing > for_each_of_graph_device_endpoint(). Getting "port" via of_get_parent() > from "endpoint" doesn't work. see below. > > ports { > port@0 { > (1) endpoint@0 {...}; > (2) endpoint@1 {...}; > }; > port@1 { > (3) endpoint {...}; > }; > ... > }; > > In other case, we want to handle "ports" same as "port" for some reasons. > > node { > => ports@0 { > port@0 { ... }; > port@1 { ... }; > ... > }; > => ports@1 { > ... > }; > }; > > Add "ports" / "port" base functions. > > Signed-off-by: Kuninori Morimoto > --- > drivers/of/property.c | 108 +++++++++++++++++++++++++++++++++++++++ > include/linux/of_graph.h | 49 ++++++++++++++++++ > 2 files changed, 157 insertions(+) > > diff --git a/drivers/of/property.c b/drivers/of/property.c > index 164d77cb94458..d99b34dd2d5b4 100644 > --- a/drivers/of/property.c > +++ b/drivers/of/property.c > @@ -625,6 +625,97 @@ struct device_node *of_graph_get_port_by_id(struct device_node *parent, u32 id) > } > EXPORT_SYMBOL(of_graph_get_port_by_id); > > +/** > + * of_graph_get_next_ports() - get next ports node. > + * @parent: pointer to the parent device node > + * @prev: previous ports node, or NULL to get first > + * > + * If "parent" node doesn't have "ports" node, it returns "parent" node itself as "ports" node. > + * > + * Return: A 'ports' node pointer with refcount incremented. Refcount > + * of the passed @prev node is decremented. > + */ > +struct device_node *of_graph_get_next_ports(struct device_node *parent, > + struct device_node *prev) > +{ > + if (!parent) > + return NULL; > + > + if (!prev) { > + /* > + * Find "ports" node from parent > + * > + * parent { > + * => ports { > + * port {...}; > + * }; > + * }; > + */ > + prev = of_get_child_by_name(parent, "ports"); > + > + /* > + * Use parent as its ports if it not exist > + * > + * => parent { > + * port {...}; > + * }; > + */ > + if (!prev) { > + /* check whether "parent" has "port" node */ > + struct device_node *port __free(device_node) = of_get_child_by_name(parent, "port"); > + > + if (port) > + prev = of_node_get(parent); > + } > + > + return prev; > + } > + > + /* Find next ports */ > + do { > + prev = of_get_next_child(parent, prev); > + if (!prev) > + break; > + } while (!of_node_name_eq(prev, "ports")); > + > + return prev; > +} > +EXPORT_SYMBOL(of_graph_get_next_ports); > + > +/** > + * of_graph_get_next_port() - get next port node. > + * @parent: pointer to the parent device node, or parent ports node > + * @prev: previous port node, or NULL to get first > + * > + * Parent device node can be used as @parent whether device node has ports node or not. > + * It will work same as ports@0 node. > + * > + * Return: A 'port' node pointer with refcount incremented. Refcount > + * of the passed @prev node is decremented. > + */ > +struct device_node *of_graph_get_next_port(struct device_node *parent, > + struct device_node *prev) > +{ > + if (!parent) > + return NULL; > + > + if (!prev) { > + struct device_node *ports __free(device_node) = > + of_graph_get_next_ports(parent, NULL); > + > + return of_get_child_by_name(ports, "port"); > + } > + > + do { > + prev = of_get_next_child(parent, prev); > + if (!prev) > + break; > + } while (!of_node_name_eq(prev, "port")); > + > + return prev; > +} > +EXPORT_SYMBOL(of_graph_get_next_port); of_graph_is_present should be reimplemented using this function. So should part of of_graph_get_next_endpoint(). Rob