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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 1971BC433E0 for ; Wed, 10 Feb 2021 08:45:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C8F7764E53 for ; Wed, 10 Feb 2021 08:45:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229898AbhBJIpO (ORCPT ); Wed, 10 Feb 2021 03:45:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51796 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230176AbhBJIne (ORCPT ); Wed, 10 Feb 2021 03:43:34 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6B285C06174A for ; Wed, 10 Feb 2021 00:42:39 -0800 (PST) Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1l9l50-0002ag-DT; Wed, 10 Feb 2021 09:42:34 +0100 Received: from sha by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1l9l4z-0006JX-HF; Wed, 10 Feb 2021 09:42:33 +0100 Date: Wed, 10 Feb 2021 09:42:33 +0100 From: Sascha Hauer To: Rob Herring Cc: linux-usb@vger.kernel.org, Minas Harutyunyan , devicetree@vger.kernel.org, kernel@pengutronix.de Subject: Re: [PATCH v2 0/2] usb: dwc2: Use clk bulk API for supporting multiple clocks Message-ID: <20210210084233.GO19583@pengutronix.de> References: <20210125093825.4292-1-s.hauer@pengutronix.de> <20210209165424.GB3909217@robh.at.kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210209165424.GB3909217@robh.at.kernel.org> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-IRC: #ptxdist @freenode X-Accept-Language: de,en X-Accept-Content-Type: text/plain X-Uptime: 09:39:30 up 69 days, 21:06, 102 users, load average: 0.01, 0.04, 0.07 User-Agent: Mutt/1.10.1 (2018-07-13) X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: sha@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-usb@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Tue, Feb 09, 2021 at 10:54:24AM -0600, Rob Herring wrote: > On Mon, Jan 25, 2021 at 10:38:23AM +0100, Sascha Hauer wrote: > > Currently the dwc2 driver only supports a single clock. I have a board > > here which has a dwc2 controller with a somewhat special clock routing > > to the phy. Both the dwc2 controller and the ULPI phy get their phy > > clock from a SI5351 clock generator. This clock generator has multiple > > clock outputs which each is modelled as a separate clk in Linux. > > Unfortunately the clock to the phy and the clock to the dwc2 core are on > > two different output pins of the SI5351, so we have two clocks which > > must be enabled. The phy is driven by the usb-nop-xceiver driver which > > supports a single clock. My first approach was to add support for a > > second clock to that driver, but technically the other clock is > > connected to the dwc2 core, so instead I added support for a second > > clock to the dwc2 driver. This can easily be archieved with the clk > > bulk API as done in this series. > > Where is the usb-nop-xceiver single clock coming from? It's coming from the SI5351 clock generator > > Maybe you shouldn't be using usb-nop-xceiver? There is a ULPI binding > though that alone doesn't really help you. The clock that feeds the phy is handled by the usb-nop-xceiver just fine, it's the clock that is fed to the DWC2 controller that I need support for. I hope my other mail makes this clearer a bit. Sascha -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |