From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 46E42C04AB4 for ; Fri, 17 May 2019 13:05:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2569E2087E for ; Fri, 17 May 2019 13:05:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728975AbfEQNFW (ORCPT ); Fri, 17 May 2019 09:05:22 -0400 Received: from mga09.intel.com ([134.134.136.24]:60150 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728683AbfEQNFW (ORCPT ); Fri, 17 May 2019 09:05:22 -0400 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 17 May 2019 06:05:21 -0700 X-ExtLoop1: 1 Received: from kuha.fi.intel.com ([10.237.72.189]) by fmsmga001.fm.intel.com with SMTP; 17 May 2019 06:05:12 -0700 Received: by kuha.fi.intel.com (sSMTP sendmail emulation); Fri, 17 May 2019 16:05:11 +0300 Date: Fri, 17 May 2019 16:05:11 +0300 From: Heikki Krogerus To: Chunfeng Yun Cc: Rob Herring , Greg Kroah-Hartman , Mark Rutland , Matthias Brugger , Adam Thomson , Li Jun , Badhri Jagan Sridharan , Hans de Goede , Andy Shevchenko , Min Guo , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, Biju Das , Linus Walleij Subject: Re: [PATCH v5 4/6] usb: roles: add API to get usb_role_switch by node Message-ID: <20190517130511.GA1887@kuha.fi.intel.com> References: <1557823643-8616-1-git-send-email-chunfeng.yun@mediatek.com> <1557823643-8616-5-git-send-email-chunfeng.yun@mediatek.com> <20190517103736.GA1490@kuha.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190517103736.GA1490@kuha.fi.intel.com> User-Agent: Mutt/1.11.4 (2019-03-13) Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Hi, On Fri, May 17, 2019 at 01:37:36PM +0300, Heikki Krogerus wrote: > On Tue, May 14, 2019 at 04:47:21PM +0800, Chunfeng Yun wrote: > > Add fwnode_usb_role_switch_get() to make easier to get > > usb_role_switch by fwnode which register it. > > It's useful when there is not device_connection registered > > between two drivers and only knows the fwnode which register > > usb_role_switch. > > > > Signed-off-by: Chunfeng Yun > > Tested-by: Biju Das > > Acked-by: Heikki Krogerus Hold on. I just noticed Rob's comment on patch 2/6, where he points out that you don't need to use device graph since the controller is the parent of the connector. Doesn't that mean you don't really need this API? > > --- > > v5 changes: > > 1. remove linux/of.h suggested by Biju > > 2. add tested by Biju > > > > Note: still depends on [1] > > [1]: [v6,08/13] usb: roles: Introduce stubs for the exiting functions in role.h > > https://patchwork.kernel.org/patch/10909971/ > > > > v4 changes: > > 1. use switch_fwnode_match() to find fwnode suggested by Heikki > > 2. this patch now depends on [1] > > > > [1] [v6,08/13] usb: roles: Introduce stubs for the exiting functions in role.h > > https://patchwork.kernel.org/patch/10909971/ > > > > v3 changes: > > 1. use fwnodes instead of node suggested by Andy > > 2. rebuild the API suggested by Heikki > > > > v2 no changes > > --- > > drivers/usb/roles/class.c | 24 ++++++++++++++++++++++++ > > include/linux/usb/role.h | 8 ++++++++ > > 2 files changed, 32 insertions(+) > > > > diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c > > index f45d8df5cfb8..4a1f09a41ec0 100644 > > --- a/drivers/usb/roles/class.c > > +++ b/drivers/usb/roles/class.c > > @@ -135,6 +135,30 @@ struct usb_role_switch *usb_role_switch_get(struct device *dev) > > } > > EXPORT_SYMBOL_GPL(usb_role_switch_get); > > > > +/** > > + * fwnode_usb_role_switch_get - Find USB role switch by it's parent fwnode > > + * @fwnode: The fwnode that register USB role switch > > + * > > + * Finds and returns role switch registered by @fwnode. The reference count > > + * for the found switch is incremented. > > + */ > > +struct usb_role_switch * > > +fwnode_usb_role_switch_get(struct fwnode_handle *fwnode) > > +{ > > + struct usb_role_switch *sw; > > + struct device *dev; > > + > > + dev = class_find_device(role_class, NULL, fwnode, switch_fwnode_match); > > + if (!dev) > > + return ERR_PTR(-EPROBE_DEFER); > > + > > + sw = to_role_switch(dev); > > + WARN_ON(!try_module_get(sw->dev.parent->driver->owner)); > > + > > + return sw; > > +} > > +EXPORT_SYMBOL_GPL(fwnode_usb_role_switch_get); This function only basically converts the fwnode to usb_role_switch, but I would actually prefer that we walked through the device graph here instead of expecting the caller to do that. So this function should probable be called fwnode_to_usb_role_switch() and not fwnode_usb_role_switch_get(), but I guess you don't need it at all, right? thanks, -- heikki