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=-12.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 1DB82C47095 for ; Mon, 5 Oct 2020 08:43:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C401A2064C for ; Mon, 5 Oct 2020 08:43:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="B6BDyc8v" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725981AbgJEInw (ORCPT ); Mon, 5 Oct 2020 04:43:52 -0400 Received: from fllv0016.ext.ti.com ([198.47.19.142]:57496 "EHLO fllv0016.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725885AbgJEInv (ORCPT ); Mon, 5 Oct 2020 04:43:51 -0400 Received: from fllv0034.itg.ti.com ([10.64.40.246]) by fllv0016.ext.ti.com (8.15.2/8.15.2) with ESMTP id 0958hkYP109357; Mon, 5 Oct 2020 03:43:46 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1601887426; bh=jh2QqHXOSUrPqqdK3EFgzaPuY0jrTqqLV5rHJjNjmRY=; h=Subject:To:CC:References:From:Date:In-Reply-To; b=B6BDyc8vJjyb8GNjzr31mCJA1+vccXTdL7nqH2NwDJHCjttOJj5F+nPscTbTMx1pJ lQ6yRkRqEZrt6DxKGBxDk0YM94tdzWws+V0NENL45vp6FpUg5ivSKS6RJDExrD6FTo l+PLG2AWXCjPsz7O156Jw6fVCXsnjxhs+ZuOFc8k= Received: from DLEE106.ent.ti.com (dlee106.ent.ti.com [157.170.170.36]) by fllv0034.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 0958hkxH100441 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 5 Oct 2020 03:43:46 -0500 Received: from DLEE102.ent.ti.com (157.170.170.32) by DLEE106.ent.ti.com (157.170.170.36) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3; Mon, 5 Oct 2020 03:43:46 -0500 Received: from lelv0326.itg.ti.com (10.180.67.84) by DLEE102.ent.ti.com (157.170.170.32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3 via Frontend Transport; Mon, 5 Oct 2020 03:43:46 -0500 Received: from [192.168.2.14] (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0326.itg.ti.com (8.15.2/8.15.2) with ESMTP id 0958hh6p067311; Mon, 5 Oct 2020 03:43:44 -0500 Subject: Re: [PATCH] usb: cdns3: platform_get_irq_byname_optional instead platform_get_irq_byname To: Pawel Laszczak , "balbi@kernel.org" CC: "peter.chen@nxp.org" , "gregkh@linuxfoundation.org" , "linux-usb@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Rahul Kumar References: <20200930065758.23740-1-pawell@cadence.com> <722fa58e-604b-bc34-d404-caf7939bb176@ti.com> From: Roger Quadros Message-ID: <5ca1fdf6-fd91-a223-92cc-a771ffa3c068@ti.com> Date: Mon, 5 Oct 2020 11:43:43 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Pawel, On 05/10/2020 08:54, Pawel Laszczak wrote: > Roger, >> >> Pawel, >> >> On 02/10/2020 12:08, Pawel Laszczak wrote: >>> Roger, >>> >>>> >>>> On 30/09/2020 09:57, Pawel Laszczak wrote: >>>>> To avoid duplicate error information patch replaces platform_get_irq_byname >>>>> into platform_get_irq_byname_optional. >>>> >>>> What is duplicate error information? >>> >>> The function platform_get_irq_byname print: >>> " dev_err(&dev->dev, "IRQ %s not found\n", name);" if error occurred. >>> >>> In core.c we have the another error message below invoking this function. >>> e.g >>> if (cdns->dev_irq < 0) >>> dev_err(dev, "couldn't get peripheral irq\n"); >>> >>> So, it's looks like one dev_err is redundant. >> >> If we want all 3 IRQs to be valid irrespective of dr_mode then we should >> use platform_get_irq_byname() and error out in probe if (ret < 0 && ret != -EPROBE_DEFER). >> >> We can get rid of the irq check and duplicate error message in other places. > > To be sure we understand each other correctly. > > Are You suggesting to leave the platform_get_irq_byname() > and rid of from core.c the following lines : > > if (cdns->dev_irq < 0) > dev_err(dev, "couldn't get peripheral irq\n"); > > and > > dev_err(dev, "couldn't get otg irq\n"); > ? Yes. > > A word of explanation why this patch has been sent. > During reviewing the cdnsp driver Chunfeng Yun add such comment: > > " >> + cdns->dev_irq = platform_get_irq_byname(pdev, "peripheral"); >> + if (cdns->dev_irq == -EPROBE_DEFER) >> + return cdns->dev_irq; >> + >> + if (cdns->dev_irq < 0) >> + dev_err(dev, "couldn't get peripheral irq\n"); > Use platform_get_irq_byname_optional? otherwise no need print this log, > platform_get_irq_byname() will print it. > " > > In this patch I've chosen the platform_get_irq_byname_optional because both > function do the same but the error message from core.c tell us little more then > generic message from platform_get_irq_byname. Using platform_get_irq_byname_optional() says driver expects it is optional but only to fail later. It will be confusing to new reader that's all. I leave it to you to decide what approach to take. cheers, -roger >> >>> >>>> >>>>> >>>>> A change was suggested during reviewing CDNSP driver by Chunfeng Yun. >>>>> >>>>> Signed-off-by: Pawel Laszczak >>>>> --- >>>>> drivers/usb/cdns3/core.c | 4 ++-- >>>>> 1 file changed, 2 insertions(+), 2 deletions(-) >>>>> >>>>> diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c >>>>> index a0f73d4711ae..a3f6dc44cf3a 100644 >>>>> --- a/drivers/usb/cdns3/core.c >>>>> +++ b/drivers/usb/cdns3/core.c >>>>> @@ -465,7 +465,7 @@ static int cdns3_probe(struct platform_device *pdev) >>>>> >>>>> cdns->xhci_res[1] = *res; >>>>> >>>>> - cdns->dev_irq = platform_get_irq_byname(pdev, "peripheral"); >>>>> + cdns->dev_irq = platform_get_irq_byname_optional(pdev, "peripheral"); >>>> >>>> As per DT binding document, these are mandatory properties >>> >>> I think that name platform_get_irq_byname_optional is little confusing. >>> Function descriptions show that both are almost identical: >>> /** >>> * platform_get_irq_byname_optional - get an optional IRQ for a device by name >>> * @dev: platform device >>> * @name: IRQ name >>> * >>> * Get an optional IRQ by name like platform_get_irq_byname(). Except that it >>> * does not print an error message if an IRQ can not be obtained. >>> * >>> * Return: non-zero IRQ number on success, negative error number on failure. >>> */ >>> >>>> >>>> - interrupts: Interrupts used by cdns3 controller: >>>> "host" - interrupt used by XHCI driver. >>>> "peripheral" - interrupt used by device driver >>>> "otg" - interrupt used by DRD/OTG part of driver >>>> >>>> for dr_mode == "otg" -> all 3 are mandatory. >>>> for dr_mode == "host" -> "otg" and "peripheral" IRQs are not required. >>>> for dr_mode == "periphearal" -> "otg" and "host" IRQs are not required. >>>> >>>>> if (cdns->dev_irq == -EPROBE_DEFER) >>>>> return cdns->dev_irq; >>>>> >>>>> @@ -477,7 +477,7 @@ static int cdns3_probe(struct platform_device *pdev) >>>>> return PTR_ERR(regs); >>>>> cdns->dev_regs = regs; >>>>> >>>>> - cdns->otg_irq = platform_get_irq_byname(pdev, "otg"); >>>>> + cdns->otg_irq = platform_get_irq_byname_optional(pdev, "otg"); >>>>> if (cdns->otg_irq == -EPROBE_DEFER) >>>>> return cdns->otg_irq; >>>>> >>>>> >>>> >>> >>> Regards, >>> Pawel >>> >> >> -- >> Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. >> Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki -- Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki