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[209.132.180.67]) by mx.google.com with ESMTP id x3-v6si3458651plo.2.2018.01.26.01.10.07; Fri, 26 Jan 2018 01:10:21 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=iOhiQ7Ca; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752738AbeAZJJC (ORCPT + 99 others); Fri, 26 Jan 2018 04:09:02 -0500 Received: from mail-pg0-f65.google.com ([74.125.83.65]:42361 "EHLO mail-pg0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752642AbeAZJI5 (ORCPT ); Fri, 26 Jan 2018 04:08:57 -0500 Received: by mail-pg0-f65.google.com with SMTP id q67so6899531pga.9; Fri, 26 Jan 2018 01:08:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=5zQkjeYrV+1IAC+zA8xTbBbc5BY+tb/0SqrYzYxlpes=; b=iOhiQ7CaJqhEMLkm2ooLSUPXDLtvAY9maWHlzb0waP4oeccih9As6oKCrk4tHZvU+n BPvjR7Vfq/2oKPiHFtThl/BWLIKxGstXcc6h6EGShaM3sV3Vx3yymxawlogleXjsUBul PxbzLsaYmSMsv5vbzy859FC4ACqgu+ljSc6pKIy161PfUpvBMsjZFKYE4mzWzIy72Vqa zYzaPgYIuH6CF39dQVn88GDCjny4i+9ywdAnqak9zCFmH12TFM4CT5Vbswzcek3z7GmD x7hC5wjPERdlo+YaaPizyPi13iihfxYi1hTQL2+RMv33vTOJRTt0t8cyrsYoW52NrrBY pobA== 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=5zQkjeYrV+1IAC+zA8xTbBbc5BY+tb/0SqrYzYxlpes=; b=ofMmug+xI8rRDLbnKK9Uk+hmm+HyOOTz7SI7RNa5qkI/RGNiVkch6hC0uimk80Hxan ejWxOSgSYfI9Kq5hb6uqbVbc5CZkMOpRQq5S61wI0kUTHAkEjCmr750FAZTFuZeTktNi P2lLpUsS8oQwLhsuiQxiX1lFuAftm0yLqkO+MWfgFyfxCmoUSbX9+pflN5FkFdyRNq/+ YJOB+i04QiDaelPOjT51nlX6IVxyj7wbtO9cJcp9cvi2nSoY/b/LHdB3KGnPTFDPokTs Ihb9HzDHqBXRAtcVfpS2OyxtqTFRvDJk/tsKAgib9EM0x4nJDaBFQA1/cnQAf5fhHI9V ABdg== X-Gm-Message-State: AKwxyteTH21bMCHvMEtIbiTykXvc/H8v06IS9taisg5SNIzaRLwYj64K ex5gztekyaTMVz8iNRBkj7vSTQ== X-Received: by 2002:a17:902:46:: with SMTP id 64-v6mr14017523pla.341.1516957737064; Fri, 26 Jan 2018 01:08:57 -0800 (PST) Received: from bai-oslab.tsinghua.edu.cn ([2402:f000:1:4413:3967:a579:e81d:66fa]) by smtp.gmail.com with ESMTPSA id e3sm18224111pfb.143.2018.01.26.01.08.54 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 26 Jan 2018 01:08:56 -0800 (PST) From: Jia-Ju Bai To: zajec5@gmail.com, hauke@hauke-m.de Cc: linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH] bcma: Replace mdelay with usleep_range in bcma_pmu_resources_init Date: Fri, 26 Jan 2018 17:13:31 +0800 Message-Id: <1516958011-303-1-git-send-email-baijiaju1990@gmail.com> X-Mailer: git-send-email 1.7.9.5 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org After checking all possible call chains to bcma_pmu_resources_init() here, my tool finds that this function is never called in atomic context, namely never in an interrupt handler or holding a spinlock. Thus mdelay can be replaced with usleep_range to avoid busy wait. This is found by a static analysis tool named DCNS written by myself. Signed-off-by: Jia-Ju Bai --- drivers/bcma/driver_chipcommon_pmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/bcma/driver_chipcommon_pmu.c b/drivers/bcma/driver_chipcommon_pmu.c index f1eb4d3..478948c 100644 --- a/drivers/bcma/driver_chipcommon_pmu.c +++ b/drivers/bcma/driver_chipcommon_pmu.c @@ -203,7 +203,7 @@ static void bcma_pmu_resources_init(struct bcma_drv_cc *cc) * Add some delay; allow resources to come up and settle. * Delay is required for SoC (early init). */ - mdelay(2); + usleep_range(1500, 2000); } /* Disable to allow reading SPROM. Don't know the adventages of enabling it. */ -- 1.7.9.5