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=ham 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 0B622C04AAF for ; Mon, 20 May 2019 08:04:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DDE562081C for ; Mon, 20 May 2019 08:04:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730610AbfETIEI (ORCPT ); Mon, 20 May 2019 04:04:08 -0400 Received: from mga18.intel.com ([134.134.136.126]:19097 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725772AbfETIEH (ORCPT ); Mon, 20 May 2019 04:04:07 -0400 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 May 2019 01:04:06 -0700 X-ExtLoop1: 1 Received: from kuha.fi.intel.com ([10.237.72.189]) by fmsmga001.fm.intel.com with SMTP; 20 May 2019 01:04:00 -0700 Received: by kuha.fi.intel.com (sSMTP sendmail emulation); Mon, 20 May 2019 11:03:59 +0300 Date: Mon, 20 May 2019 11:03:59 +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: <20190520080359.GC1887@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> <20190517130511.GA1887@kuha.fi.intel.com> <1558319951.10179.352.camel@mhfsdcap03> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1558319951.10179.352.camel@mhfsdcap03> User-Agent: Mutt/1.11.4 (2019-03-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 20, 2019 at 10:39:11AM +0800, Chunfeng Yun wrote: > Hi, > On Fri, 2019-05-17 at 16:05 +0300, Heikki Krogerus wrote: > > 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? > No, I still need it. > The change is about the way how to get fwnode; > when use device graph, get fwnode by of_graph_get_remote_node(); > but now will get fwnode by of_get_parent(); OK, I get that, but I'm still not convinced about if something like this function is needed at all. I also have concerns regarding how you are using the function. I'll explain in comment to the patch 5/6 in this series... > > > > --- > > > > 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 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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,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 D5B51C04AAF for ; Mon, 20 May 2019 08:04:17 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AC4C02081C for ; Mon, 20 May 2019 08:04:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="izpIPnJv" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AC4C02081C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=KNGDNA3DKfNRsqJe/gDcBaqZ+0v4NPBzN8d7TYgcZAw=; b=izpIPnJvbjtBWP SkaYAJWiby5iVE+JSFr81hwUS9ibft7hIiNgmyalDFLN9YA1YIeQNKzHjyC/3d/43XJ6q2IuY3PhM wpvr/uf4AxMYfNs/4tS9iop3MRktrcOBBt7CfEdMDKkeVF7zCfAlSYsY+zq4tTRTKcBgmyIvv11Na Hg+LMzM25ejC2l6eoKn7fIPXNNSAPCjW1bwws0J/iflPl4PZgRRnH9h8RochvLW7Ck8TNKEo6H1Bi 95ISiMESGh8WaCmelhr8OiN1YARowEcii9yTHaiMjf45pwbqfcr5Vt57t9hpiRHe+VQZlVITmUJLV fieOBOSoQ3gaCI1TlQdw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hSdHH-0007sS-2o; Mon, 20 May 2019 08:04:11 +0000 Received: from mga01.intel.com ([192.55.52.88]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hSdHD-0007rp-7O; Mon, 20 May 2019 08:04:08 +0000 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 May 2019 01:04:06 -0700 X-ExtLoop1: 1 Received: from kuha.fi.intel.com ([10.237.72.189]) by fmsmga001.fm.intel.com with SMTP; 20 May 2019 01:04:00 -0700 Received: by kuha.fi.intel.com (sSMTP sendmail emulation); Mon, 20 May 2019 11:03:59 +0300 Date: Mon, 20 May 2019 11:03:59 +0300 From: Heikki Krogerus To: Chunfeng Yun Subject: Re: [PATCH v5 4/6] usb: roles: add API to get usb_role_switch by node Message-ID: <20190520080359.GC1887@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> <20190517130511.GA1887@kuha.fi.intel.com> <1558319951.10179.352.camel@mhfsdcap03> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1558319951.10179.352.camel@mhfsdcap03> User-Agent: Mutt/1.11.4 (2019-03-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190520_010407_275197_E3EC6C8E X-CRM114-Status: GOOD ( 30.65 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , devicetree@vger.kernel.org, Hans de Goede , Greg Kroah-Hartman , Linus Walleij , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Biju Das , Badhri Jagan Sridharan , Andy Shevchenko , Rob Herring , linux-mediatek@lists.infradead.org, Min Guo , Matthias Brugger , Adam Thomson , linux-arm-kernel@lists.infradead.org, Li Jun Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, May 20, 2019 at 10:39:11AM +0800, Chunfeng Yun wrote: > Hi, > On Fri, 2019-05-17 at 16:05 +0300, Heikki Krogerus wrote: > > 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? > No, I still need it. > The change is about the way how to get fwnode; > when use device graph, get fwnode by of_graph_get_remote_node(); > but now will get fwnode by of_get_parent(); OK, I get that, but I'm still not convinced about if something like this function is needed at all. I also have concerns regarding how you are using the function. I'll explain in comment to the patch 5/6 in this series... > > > > --- > > > > 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 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel