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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 78A1CC3A5A1 for ; Thu, 22 Aug 2019 17:12:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4E8D22089E for ; Thu, 22 Aug 2019 17:12:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566493971; bh=yoK6E85K/l2xZlICnFSN1g8SzZTgncSSZLt/CSFHhmU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=HjdDq0KL/KUHSsmTOE8aGr1If4NAqSt6/Ahvq4alDJibl3v8I4huDAX8duYM3mvE0 7PrfkQXttvxtgw/SV4h9H5DcQJ1EigzAERtVDGqOAzjHSdgDr36MOq65mtTFEsrlAm Yo8H0R664xSGTkjW0hgWF3V0klj3tmldwIUo70Uc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389332AbfHVRMu (ORCPT ); Thu, 22 Aug 2019 13:12:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:59306 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390654AbfHVRJG (ORCPT ); Thu, 22 Aug 2019 13:09:06 -0400 Received: from sasha-vm.mshome.net (wsip-184-188-36-2.sd.sd.cox.net [184.188.36.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 230A72342A; Thu, 22 Aug 2019 17:09:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566493745; bh=yoK6E85K/l2xZlICnFSN1g8SzZTgncSSZLt/CSFHhmU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aWHd/DeT/dd3eqJbYoyG8AmRUDXRDOLOC77kW4XKncclaUAIUO5OWLKbMj8KD/oxi sFb7EN2Q8yHu3tFKVpIxPdeY6Ixn4PaCnffnBYtcUjWkdO+0ijuVVXfLZXRNt9V/dS YlNfNwrW8aoDzViejEHYjZsOgVXHsGszwbHTydsc= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Ian Abbott , Greg Kroah-Hartman Subject: [PATCH 5.2 093/135] staging: comedi: dt3000: Fix rounding up of timer divisor Date: Thu, 22 Aug 2019 13:07:29 -0400 Message-Id: <20190822170811.13303-94-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190822170811.13303-1-sashal@kernel.org> References: <20190822170811.13303-1-sashal@kernel.org> MIME-Version: 1.0 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.2.10-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-5.2.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 5.2.10-rc1 X-KernelTest-Deadline: 2019-08-24T17:07+00:00 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ian Abbott commit 8e2a589a3fc36ce858d42e767c3bcd8fc62a512b upstream. `dt3k_ns_to_timer()` determines the prescaler and divisor to use to produce a desired timing period. It is influenced by a rounding mode and can round the divisor up, down, or to the nearest value. However, the code for rounding up currently does the same as rounding down! Fix ir by using the `DIV_ROUND_UP()` macro to calculate the divisor when rounding up. Also, change the types of the `divider`, `base` and `prescale` variables from `int` to `unsigned int` to avoid mixing signed and unsigned types in the calculations. Also fix a typo in a nearby comment: "improvment" => "improvement". Signed-off-by: Ian Abbott Cc: stable Link: https://lore.kernel.org/r/20190812120814.21188-1-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/dt3000.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/staging/comedi/drivers/dt3000.c b/drivers/staging/comedi/drivers/dt3000.c index 4ad176fc14ad1..caf4d4df4bd30 100644 --- a/drivers/staging/comedi/drivers/dt3000.c +++ b/drivers/staging/comedi/drivers/dt3000.c @@ -342,9 +342,9 @@ static irqreturn_t dt3k_interrupt(int irq, void *d) static int dt3k_ns_to_timer(unsigned int timer_base, unsigned int *nanosec, unsigned int flags) { - int divider, base, prescale; + unsigned int divider, base, prescale; - /* This function needs improvment */ + /* This function needs improvement */ /* Don't know if divider==0 works. */ for (prescale = 0; prescale < 16; prescale++) { @@ -358,7 +358,7 @@ static int dt3k_ns_to_timer(unsigned int timer_base, unsigned int *nanosec, divider = (*nanosec) / base; break; case CMDF_ROUND_UP: - divider = (*nanosec) / base; + divider = DIV_ROUND_UP(*nanosec, base); break; } if (divider < 65536) { -- 2.20.1