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=-7.7 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,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 C3D6BC43461 for ; Fri, 4 Sep 2020 14:04:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8C74220684 for ; Fri, 4 Sep 2020 14:04:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=arf.net.pl header.i=@arf.net.pl header.b="gKQwO9iy" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730633AbgIDOEZ (ORCPT ); Fri, 4 Sep 2020 10:04:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730599AbgIDOBG (ORCPT ); Fri, 4 Sep 2020 10:01:06 -0400 Received: from ipv6.s19.hekko.net.pl (ipv6.s19.hekko.net.pl [IPv6:2a02:1778:113::19]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7451DC061247; Fri, 4 Sep 2020 07:01:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=arf.net.pl; s=x; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:MIME-Version:Date: Message-ID:From:References:Cc:To:Subject:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=hEP46ZA6ePHrwQkWvRFQ6iFofIiyW4GUhLIggfpPhx0=; b=gKQwO9iyk/2sWho9Mvuf1cqDxn 3181MQpZ7sI+rEyM734NAJw8e0Aw475FUeuRZBA6pbiWujl6HEDa6qiER9CTunZFAKVVgrJ2JKTFJ 2YcgKz+Nh62HqyFyjvnaw+m02RFiROdeJV/8ytqFfogZCb42BmiNUj3i9Bm9iDuSqwN6iuH0SmNrV 8pcvUs2hIb5IMGxQ+lF1TG2PzkHWxxvxYqXsOrlMRaUdLOM8ZTBFJTIGZyxnSbIsoQDchY7334DZR tfdai1NX8T6syGl1YEfbvrM2BsqzVVQJkf+6rqijWamyMgp6lwJK+ifqiij42wEoOCEThOk39RBtz sh1QbgjQ==; Received: from 188.147.96.44.nat.umts.dynamic.t-mobile.pl ([188.147.96.44] helo=[192.168.8.103]) by s19.hekko.net.pl with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.92.3) (envelope-from ) id 1kECGr-000sWO-Ho; Fri, 04 Sep 2020 16:00:53 +0200 Subject: Re: [PATCH net-next 0/3] net: phy: Support enabling clocks prior to bus probe To: Andrew Lunn Cc: Florian Fainelli , netdev@vger.kernel.org, m.felsch@pengutronix.de, hkallweit1@gmail.com, richard.leitner@skidata.com, zhengdejin5@gmail.com, devicetree@vger.kernel.org, kernel@pengutronix.de, kuba@kernel.org, robh+dt@kernel.org References: <20200903043947.3272453-1-f.fainelli@gmail.com> <307b343b-2e8d-cb20-c22f-0e80acdf1dc9@arf.net.pl> <20200904134558.GL3112546@lunn.ch> From: =?UTF-8?Q?Adam_Rudzi=c5=84ski?= Message-ID: Date: Fri, 4 Sep 2020 16:00:55 +0200 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <20200904134558.GL3112546@lunn.ch> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: pl X-Authenticated-Id: ar@arf.net.pl Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org W dniu 2020-09-04 o 15:45, Andrew Lunn pisze: >> Just a bunch of questions. >> >> Actually, why is it necessary to have a full MDIO bus scan already during >> probing peripherals? > That is the Linux bus model. It does not matter what sort of bus it > is, PCI, USB, MDIO, etc. When the bus driver is loaded, the bus is > enumerated and drivers probe for each device found on the bus. OK. But is it always expected to find all the devices on the bus in the first run? Does the bus model ever allow to just add any more devices? Kind of, "hotplug". :) >> I'd say that it is not necessary to have a PHY getting found before it is >> needed to setup the complete interface. > It is like saying, we don't need to probe the keyboard until the first > time the "Press Enter" prompt is given? I'm not sure what you mean. It's like saying that we don't need to care if we even have the keyboard until we are interested in any interaction with it. (This might be reading a key, an autotest, ..., or not using, but avoiding a conflict - depends on application.) Best regards, Adam