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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D8148C433F5 for ; Wed, 16 Feb 2022 09:41:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232239AbiBPJmI (ORCPT ); Wed, 16 Feb 2022 04:42:08 -0500 Received: from gmail-smtp-in.l.google.com ([23.128.96.19]:50698 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229660AbiBPJmG (ORCPT ); Wed, 16 Feb 2022 04:42:06 -0500 Received: from mail-lj1-x22c.google.com (mail-lj1-x22c.google.com [IPv6:2a00:1450:4864:20::22c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B3B49E0AEB for ; Wed, 16 Feb 2022 01:41:52 -0800 (PST) Received: by mail-lj1-x22c.google.com with SMTP id e17so2395208ljk.5 for ; Wed, 16 Feb 2022 01:41:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=QaNwt9SQ6DzRbNAGLtqtMU6nrQKeqSfmU6yrI7LzU0Y=; b=KkCea7osivyB9FSw2DaT9jDfa0MzzKtbLlXCAJy8GXyJITuiG0eo3WV7Bij2TNY98v DeBBrjIxibIEV0CMaOHYfhc/a7pbRjrSHvTCNW7pvUdb+wEYuguQnmN4sx1d+TGAnXQS r4yzCe08uAbJT9W5ewyH1vBeWSCz/Tz1smB9M/mhId7LOj5KWgZJmVnq7agZdIAa/xSr JW+exTCxPF18fCokPVF30Ox+V80Ss9miet9nx/c2OCKmaS0Uxt9QKTsjSRjKpd2TX3iE P5SziC1mdPRXtG/kADH1lUVVdMkD7n+wEv8fmxdxrPDvjfd04JfpFiVUlNtiG7ZJCNBH 23jA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=QaNwt9SQ6DzRbNAGLtqtMU6nrQKeqSfmU6yrI7LzU0Y=; b=ZdoPieEJiUpUb0HU6hmGOABKpWeMo+7eCX126jI10xFg6DI3/yXF4AAGtxIZJShV1q TbiyiWwggXdmOTiId9pkUay3qvqYE8nr56jQxkkkKCAnxvFVnEaQhvVIYepR5OkRGmOo fM3og3LHpnDn6kyO8pYCCz6si+W/n93Lk7MlvhubcPDrgivV2qfQu4YTkkBBDpQNFvaU QpHpEPDYxTg/4oa74hnuvC07T7PIxaQYeyhORsqgkMcW2czR7OVOyzUN3czORWtNRqa3 HNGIiodtp8wuBWltouJkPIM/ymOIYcsp4+AWZZBd9RSc3GRz13oQ5uAMlnoYWBEqLyn7 PS5w== X-Gm-Message-State: AOAM530agbtqu5UAD/zST1+EaGyY/VW/V7Q9Iv15/or1CO5CMz+PyL4J 8DMWV34h4J4AZN5xpg58R54= X-Google-Smtp-Source: ABdhPJw4H6I7xWX0In3K8NmI6N1uXmUrxifxlgx9dKyUQkLTy1zmdHIQ2CEZjgb9nNINRinI8w1Zrg== X-Received: by 2002:a2e:3c06:0:b0:245:a3b8:aacf with SMTP id j6-20020a2e3c06000000b00245a3b8aacfmr1362819lja.241.1645004510933; Wed, 16 Feb 2022 01:41:50 -0800 (PST) Received: from [192.168.1.103] ([31.173.81.81]) by smtp.gmail.com with ESMTPSA id t15sm164562lfp.91.2022.02.16.01.41.49 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 16 Feb 2022 01:41:50 -0800 (PST) Subject: Re: [PATCH 1/5] usb: host: xhci: use ffs() in xhci_mem_init() To: Linyu Yuan , Mathias Nyman , Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org, Jack Pham References: <1644994755-12975-1-git-send-email-quic_linyyuan@quicinc.com> <1644994755-12975-2-git-send-email-quic_linyyuan@quicinc.com> From: Sergei Shtylyov Message-ID: <4688f5bb-c0fd-bbce-de1f-a554d543ed03@gmail.com> Date: Wed, 16 Feb 2022 12:41:49 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: <1644994755-12975-2-git-send-email-quic_linyyuan@quicinc.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Hello! On 2/16/22 9:59 AM, Linyu Yuan wrote: > The for loop to find page size bit can be replaced with ffs(). > > Signed-off-by: Linyu Yuan > --- > drivers/usb/host/xhci-mem.c | 7 +------ > 1 file changed, 1 insertion(+), 6 deletions(-) > > diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c > index 0e31206..3cbc7f2 100644 > --- a/drivers/usb/host/xhci-mem.c > +++ b/drivers/usb/host/xhci-mem.c > @@ -2395,12 +2395,7 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags) > page_size = readl(&xhci->op_regs->page_size); > xhci_dbg_trace(xhci, trace_xhci_dbg_init, > "Supported page size register = 0x%x", page_size); > - for (i = 0; i < 16; i++) { > - if ((0x1 & page_size) != 0) > - break; > - page_size = page_size >> 1; > - } > - if (i < 16) > + if ((i = ffs(page_size)) < 16) Always run your patches thru scripts/checkpatch.pl -- in this case it will complain of an assignment in the *if* expression... [...] MNR, Sergey