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=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS 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 7B09FC46475 for ; Mon, 5 Nov 2018 13:19:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 43A9D2081D for ; Mon, 5 Nov 2018 13:19:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="QB/c7l/H" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 43A9D2081D Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=ti.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729759AbeKEWjk (ORCPT ); Mon, 5 Nov 2018 17:39:40 -0500 Received: from lelv0143.ext.ti.com ([198.47.23.248]:38452 "EHLO lelv0143.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728966AbeKEWjk (ORCPT ); Mon, 5 Nov 2018 17:39:40 -0500 Received: from fllv0034.itg.ti.com ([10.64.40.246]) by lelv0143.ext.ti.com (8.15.2/8.15.2) with ESMTP id wA5DJk8r111409; Mon, 5 Nov 2018 07:19:46 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1541423986; bh=0CfviIyKy8oc58C8tbJxtaXziewxsJyfyeg+1G1u6/4=; h=Subject:To:CC:References:From:Date:In-Reply-To; b=QB/c7l/HVUDlnRP9PSDZ38wgP7QA6gRI7Yey3rL5WfAGgwmS001VLdaCSRI1kU9Dh kc9RkNpaW3rGC7oeIsg0GZBSjANVbZxx4ttFbWtkZcpa97HFjfp5mFfTYIQYQgqHaK 9nU6SMoSNEa/My6RR7jzLzQMihSB5FZNfUVBcPuw= Received: from DFLE104.ent.ti.com (dfle104.ent.ti.com [10.64.6.25]) by fllv0034.itg.ti.com (8.15.2/8.15.2) with ESMTPS id wA5DJkdc058387 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 5 Nov 2018 07:19:46 -0600 Received: from DFLE103.ent.ti.com (10.64.6.24) by DFLE104.ent.ti.com (10.64.6.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1466.3; Mon, 5 Nov 2018 07:19:46 -0600 Received: from dlep33.itg.ti.com (157.170.170.75) by DFLE103.ent.ti.com (10.64.6.24) with Microsoft SMTP Server (version=TLS1_0, cipher=TLS_RSA_WITH_AES_256_CBC_SHA) id 15.1.1466.3 via Frontend Transport; Mon, 5 Nov 2018 07:19:46 -0600 Received: from [172.24.190.215] (ileax41-snat.itg.ti.com [10.172.224.153]) by dlep33.itg.ti.com (8.14.3/8.13.8) with ESMTP id wA5DJh8p026903; Mon, 5 Nov 2018 07:19:43 -0600 Subject: Re: [PATCH 1/6] phy: Add max_bitrate attribute & phy_get_max_bitrate() To: Marc Kleine-Budde , , , , CC: , , , References: <20181102192616.28291-1-faiz_abbas@ti.com> <20181102192616.28291-2-faiz_abbas@ti.com> <5e1a0b67-510a-5512-d477-0b363e4733fe@pengutronix.de> <0c0885c4-f5ae-a29c-7176-f67fe546cfd8@pengutronix.de> <5685cb49-a6bf-3696-f984-020847633e5e@ti.com> <1e708b81-ed63-7dbf-3120-d256c0ec76c6@pengutronix.de> From: Faiz Abbas Message-ID: Date: Mon, 5 Nov 2018 18:52:22 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <1e708b81-ed63-7dbf-3120-d256c0ec76c6@pengutronix.de> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Marc, On Monday 05 November 2018 05:17 PM, Marc Kleine-Budde wrote: > On 11/05/2018 12:14 PM, Faiz Abbas wrote: >> Hi, >> >> On Monday 05 November 2018 03:07 PM, Marc Kleine-Budde wrote: >>> On 11/05/2018 07:27 AM, Faiz Abbas wrote: >>>> I remove the transceiver child node binding documentation in patch 5/6. >>>> >>>> The existing implementation is pretty limiting as it just has a child >>>> node with no associated device. What if a transceiver requires its own >>>> configurations before it can start sending/receiving messages (for >>>> example, my usecase requires it to pull the standby line low)? >>>> >>>> I think that can be solved by implementing the transceiver as a phy and >>>> exposing a generic get_max_bitrate API. That way, the transceiver device >>>> can do all its startup configuration in the phy probe function. >>>> >>>> In any case, do suggest if you have a better idea on how to implement >>>> pull gpio low requirement. >>> >>> As long as we don't have any proper transceiver/phy driver, that does >>> more than swtich on/off a GPIO, please add a "xceiver" regulator to your >>> driver. Look for: >>> >>>> devm_regulator_get(&pdev->dev, "xceiver"); >>> >> >> The transceiver is not specific to m_can. The pull down would be >> required even if it were connected to some other controller. > > Ok, this is a quite common pattern. For the fsl/nxp boards we add the > regulator to the board dts. See "imx28-evk.dts" for example: > >> can0: can@80032000 { >> pinctrl-names = "default"; >> pinctrl-0 = <&can0_pins_a>; >> xceiver-supply = <®_can_3v3>; >> status = "okay"; >> }; >> >> can1: can@80034000 { >> pinctrl-names = "default"; >> pinctrl-0 = <&can1_pins_a>; >> xceiver-supply = <®_can_3v3>; >> status = "okay"; >> }; > Ok. Will implement that in v2. Thanks, Faiz