Received: by 10.223.176.46 with SMTP id f43csp897228wra; Fri, 26 Jan 2018 08:34:52 -0800 (PST) X-Google-Smtp-Source: AH8x2250qkTojXDb7DlCtC5anTqUbuOnY+FfaWYZAT9vLj7QqWUp16utA/lr8YlhPMfRDFQ5mnQb X-Received: by 10.99.60.88 with SMTP id i24mr15990242pgn.1.1516984492076; Fri, 26 Jan 2018 08:34:52 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1516984492; cv=none; d=google.com; s=arc-20160816; b=f7cBumJCVpw8DL+Rx1OX9hyUiRMmtQ0D0+RZ3+t3NOw5nb3R4XDt/Fz2wL2WTsmh8i 0lbW7ATdMEx7raNWQtenKCbi4dfBKBqr1hxzbFdfv4Pb6ZporE5Xep2vs/0MoTR7b718 OpLmnoclAxCqX7WFNqEhZ0YbCujCsmSRqoUNdHrcIRglYcslQ4sk0WzsuuPncJP8ldhQ 1v+98aBBBT6eK4t/byYvL8b81LEkSbfJtCMnuF+UdedtXxFfecU3Z+fWbA/NiZ5EIAvc YknMnzHE1ZoJkI4Im2OdGbxjGhg/KaOJaYM7GqmWP1RAdGvbkFcU0Wc5c3UZgxmDajh6 dzWQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:message-id:date:subject:cc:to:from :dkim-signature:arc-authentication-results; bh=rz1ta+ej/iJ1udz7A5P7rT6+XeuL14GCxf94KhxGDoI=; b=S/Ht/kB1ZiCWSYoqY+gmHnX0mocr+5styAz/uABxDZK/8j9UY8qyJw1IlhczxZLmW2 FE1Fmm/DKrqfFcC7XfYk7vOjXcTP43TWkwyurLV9v74XPge98b8No/RFuxysJ7wfjNZJ w9S+hZZ69LcouAO0ztyNaOHec8cBPZxpVeFNMMi0sIchpWUg1/PD/z0xWHLAx8BGOEBt DjnbUcPGFX9g4YpxQbXJNQFiYarQ1ihX1sk4Tzh4KuQDHXQvLdELGFNVO3YuNI+BRMJd vL+R6w5WkJ9V9FVVS1dH6HGdyBpKohd/LfIHrB7GruDxpUR4/DE0IrjZb77GUl5dlyPg BjBg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=DyMtdH9G; 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 Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id w22-v6si4037420plk.66.2018.01.26.08.34.38; Fri, 26 Jan 2018 08:34:52 -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=DyMtdH9G; 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 S1752174AbeAZQeD (ORCPT + 99 others); Fri, 26 Jan 2018 11:34:03 -0500 Received: from mail-pf0-f193.google.com ([209.85.192.193]:43870 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752041AbeAZQeA (ORCPT ); Fri, 26 Jan 2018 11:34:00 -0500 Received: by mail-pf0-f193.google.com with SMTP id y26so577839pfi.10; Fri, 26 Jan 2018 08:34:00 -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=rz1ta+ej/iJ1udz7A5P7rT6+XeuL14GCxf94KhxGDoI=; b=DyMtdH9Gw+koWiQ9CGRbou9r/Jc7PLj2Cb6h9jnTv9X75G2ZlXzsdLjXIWzpdQaGYb SLMUJK+/HlyVm4oHn6QfKAq8LYv6sT/f5TVfTD9Vla1tZ+kEgwI9xk+K7G20C7lQP8id 89rf8+g3jXg0g+6B3QmYtxKOKEeC0YPQnYi7ryymRxM2RhAk1KC7SiQ/UGWdnHvG8qYW vWE4SXSWlW9fgieNhoI3E5QDxVSUeM3s7ii7zyt1vNZAwdKc6HQzQ0wLDk8dJvaCPveq huylUcRrWm8+8rmum2kGGTw66kjEwFbt8vzmnmYBHee7Q5i/9JGqcLovQ6D9pH20FXye hJFQ== 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=rz1ta+ej/iJ1udz7A5P7rT6+XeuL14GCxf94KhxGDoI=; b=O9g6zTXf6BBNvpmi99Qb7vCTCv2dcd8el9ZRwGTgIWMqT8qa945f1t1gGxGyfqHFIT nogKM8HjBkTpTH+bxSnVm+chQHiZeC69qxwlyKekyRC67UhLOYSWEVk/CnQR5bJpr2f4 z0cHHIy5WY74cS593gBUQ7Fw6Q6cxDpt4xygI9msIJu8Ishdsu5wM+sN4APrWcNLiKWJ YiMyoyIhtMS8ykF9jWxruJ1WPFesjJCnQOLzwQ6Nnw88/M1tl5USTH9mISpGD52InOnL VH7GX7wKfFwIqZSOw+QWuLzqX5gjCbR8D/ed2z6zuiDwx4PSgOsQzBoDSb9jGTp4t1bJ viUg== X-Gm-Message-State: AKwxyteYw0BCyOLoBxXs210iaM+3y9UWsnTIFow9m6S9nJHjw6W7TO07 WyU2ndkyxgINtdPttfpV2JM= X-Received: by 10.101.68.82 with SMTP id e18mr14975956pgq.413.1516984439858; Fri, 26 Jan 2018 08:33:59 -0800 (PST) Received: from bai-oslab.tsinghua.edu.cn ([2402:f000:1:4413:3967:a579:e81d:66fa]) by smtp.gmail.com with ESMTPSA id t21sm19633142pfe.122.2018.01.26.08.33.57 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 26 Jan 2018 08:33:59 -0800 (PST) From: Jia-Ju Bai To: Larry.Finger@lwfinger.net, kvalo@codeaurora.org, zajec5@gmail.com Cc: linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH v2] bcma: Replace mdelay with usleep_range in bcma_pmu_resources_init Date: Sat, 27 Jan 2018 00:38:35 +0800 Message-Id: <1516984715-9237-1-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 --- v2: * Use usleep_range(2000, 2500), instead of (1500, 2000) in v1. --- 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(2000, 2500); } /* Disable to allow reading SPROM. Don't know the adventages of enabling it. */ -- 1.7.9.5