From patchwork Mon Apr 9 13:03:38 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jia-Ju Bai X-Patchwork-Id: 10331301 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 2314960236 for ; Mon, 9 Apr 2018 13:03:55 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1460628A09 for ; Mon, 9 Apr 2018 13:03:55 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 093E628A1B; Mon, 9 Apr 2018 13:03:55 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.8 required=2.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 19AEA28A09 for ; Mon, 9 Apr 2018 13:03:53 +0000 (UTC) Received: from alsa0.perex.cz (localhost [127.0.0.1]) by alsa0.perex.cz (Postfix) with ESMTP id A73F12675DF; Mon, 9 Apr 2018 15:03:52 +0200 (CEST) X-Original-To: alsa-devel@alsa-project.org Delivered-To: alsa-devel@alsa-project.org Received: by alsa0.perex.cz (Postfix, from userid 1000) id 6D0712675DF; Mon, 9 Apr 2018 15:03:50 +0200 (CEST) Received: from mail-pf0-f193.google.com (mail-pf0-f193.google.com [209.85.192.193]) by alsa0.perex.cz (Postfix) with ESMTP id 899622675FA for ; Mon, 9 Apr 2018 15:03:45 +0200 (CEST) Received: by mail-pf0-f193.google.com with SMTP id o16so5730494pfk.9 for ; Mon, 09 Apr 2018 06:03:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=VtFvdV4UzYTvg1ZEfvH1DA86rokF+JiO5hrUQyxMaSQ=; b=fPPHif6FD7H3v9JT/7nCPKUBiA64/FP0gZPNGHzTc5UiPfPnjRBb2I8+XvOJTxh0Qe I73VN8t9X+eMe2Rgni26YjNkBMfdi4o31MmSqHa6dg/YLFg3KQJgDYMHHGfydDmhDdND 7hL7+rd9g9/STTOiWob3pNG4qn3xuFipMQufpiA9JAS0314Il4Wsv3SSVFTitQFvoEL4 gMEZqhmdXTxViBI1+GBnvq7x5GwExu3lfGGZF7jHELyj9GHMfX4ogwqR/8DJbZvUBEaH AQHfvLihdpsUvilR+Rmc/fVUzsCaqofe8LbA/KBANrQ74Pznw3mo9ac4K2TgPbX11nV1 IgeQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=VtFvdV4UzYTvg1ZEfvH1DA86rokF+JiO5hrUQyxMaSQ=; b=Kousr0KfCLVv/VeLpHpfOA+uofYnk58eBx0dUKbcBAV1wsCLe/1ec3DqLRfEIdgiIQ tVDUZEXidMPNGNJJwlrDCyJqt9Y0xTXgh+jD3W7aPc6rXR9OLolcyOYzz6LpNgH9AQqy xOfHkWac8mgSQ5gDD5tZkNDN8o1lpZJP3sh8s/YKDrX5I1ySOvgELeS6BG7Fuo1RLSGu k4FygFZpyKNGCnirAK6cMGrV2ykPU+/Ek5IHk1npZ3WONsqF3RIWxUpTPBtVqmkdcRI+ H+vB47MYrb/cR91NovnkFnZxeYECO9hfLn5xDVOlYTAFAr8eEWtwAsn/PyJaG3sn96rS B9lA== X-Gm-Message-State: AElRT7FwUIrU+ULf/YoaRQeO2FeNRP5ybsGZM17eEoDttkK329IpUiCA w3tuE5DEQFqlXgGOsbitVhc= X-Google-Smtp-Source: AIpwx486wri9NwmZYHfbp79BtnlTrC/6RkppW9tPoZtjrMIwWwL5tkDrARbqTDnfGJ+wrt/ytQlv9A== X-Received: by 10.99.169.1 with SMTP id u1mr25751806pge.251.1523279025159; Mon, 09 Apr 2018 06:03:45 -0700 (PDT) Received: from oslab.tsinghua.edu.cn ([2402:f000:1:4413:39e9:70fb:21a6:f4d2]) by smtp.gmail.com with ESMTPSA id r20sm1382623pff.165.2018.04.09.06.03.42 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 09 Apr 2018 06:03:44 -0700 (PDT) From: Jia-Ju Bai To: T-Bone@parisc-linux.org, perex@perex.cz, tiwai@suse.com Date: Mon, 9 Apr 2018 21:03:38 +0800 Message-Id: <1523279018-24017-1-git-send-email-baijiaju1990@gmail.com> X-Mailer: git-send-email 1.9.1 Cc: alsa-devel@alsa-project.org, Jia-Ju Bai , linux-kernel@vger.kernel.org, linux-parisc@vger.kernel.org Subject: [alsa-devel] [PATCH 2/2] sound: ad1889: Replace mdelay with usleep_range in snd_ad1889_ac97_ready X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org X-Virus-Scanned: ClamAV using ClamSMTP snd_ad1889_ac97_ready() is never called in atomic context. The call chain ending up at snd_ad1889_ac97_ready() is: [1] snd_ad1889_ac97_ready() <- snd_ad1889_ac97_xinit() <- snd_ad1889_ac97_init() <- snd_ad1889_probe() snd_ad1889_probe() is only set as ".probe" in struct pci_driver. This function is not called in atomic context. Despite never getting called from atomic context, snd_ad1889_ac97_ready() calls mdelay for busy wait. This is not necessary and can be replaced with usleep_range to avoid busy waiting. This is found by a static analysis tool named DCNS written by myself. Signed-off-by: Jia-Ju Bai --- sound/pci/ad1889.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sound/pci/ad1889.c b/sound/pci/ad1889.c index 0bf2c04..a2a8e1d 100644 --- a/sound/pci/ad1889.c +++ b/sound/pci/ad1889.c @@ -258,7 +258,7 @@ struct snd_ad1889 { while (!(ad1889_readw(chip, AD_AC97_ACIC) & AD_AC97_ACIC_ACRDY) && --retry) - mdelay(1); + usleep_range(1000, 2000); if (!retry) { dev_err(chip->card->dev, "[%s] Link is not ready.\n", __func__);