From patchwork Wed Sep 6 13:13:07 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 111776 Delivered-To: patch@linaro.org Received: by 10.140.94.166 with SMTP id g35csp850937qge; Wed, 6 Sep 2017 06:13:52 -0700 (PDT) X-Google-Smtp-Source: ADKCNb47msUoQ6yQiXQv5uGhz1YYvJ4hSZixS/dUc5xpspAnRiPvagwhbQWMbE5secvIlbM9FHP6 X-Received: by 10.98.160.29 with SMTP id r29mr7340501pfe.176.1504703631972; Wed, 06 Sep 2017 06:13:51 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1504703631; cv=none; d=google.com; s=arc-20160816; b=tUWt9luCC9oBkRWdBNF4+S6JD88QgABtUPkC0t7cy1U3kHePVIL2iNMhiC8uty3p9w u5ZqCIpOi77HxbBSyG7+Ax87Ra7XdYbNbYijhm0Otb1KU/BU0rZsUoFjXPe+R+Vzp6Qz Yas3QdUmnIvUwE9m8IpLZbbSo3vMeW7s/xiWvjfZbdI/4mr8Ab6bcT2z+OmCqfmJXiHn WcnTh5Wt79fKAbUGqJUGyZh/Hy2vAfC25c4F8/C05yNzbGDe27jQeZAxeM/3WhLvdukD Ah/a1QTVnBD73K4UqHX9xv0x1dd4Tp7b0vwK+VUDescDxBm7vquqSgBkDlqj1Y1Azax5 FXnw== 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 :arc-authentication-results; bh=vlBUptOb1y5TBLOFM8qa1PwIdscmPlUy+hqtg1BAqk0=; b=KQuYZI4emKS47ObTG+SLeQAeqyVWMa0SOCgqbSnIcnhntPolSrF5nydbVGS6ZDOlLN 5+g8lYJjCRyxxkOb6x7CsQIQu3hgQf7/gvCuQ8ecVyyfyQmWr4Ec+7GKfrrWKcuXebG5 qYdpui9a8bYnajYQzRIwPp3lwA/wMFZzCO+C7f7rSXnoDooyng2S6Ug3mhu23VSJVyFZ MxYkwCMaeRoPvAOJJ2QbsM+axtZYw1pA1gGbZbSgTaQO7WTwBdnmZar3/IoZ3gNBycrQ onhHgspdWisckRpZzPJHFoEvpf9W32vQpQaL6GqZ9htccpjrXo1q2zn6KLX5uxY0ykiX F1NQ== ARC-Authentication-Results: i=1; mx.google.com; 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 Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id e6si1184660pgr.74.2017.09.06.06.13.51; Wed, 06 Sep 2017 06:13:51 -0700 (PDT) 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; 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 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753676AbdIFNNt (ORCPT + 26 others); Wed, 6 Sep 2017 09:13:49 -0400 Received: from mout.kundenserver.de ([212.227.126.134]:61713 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753025AbdIFNNo (ORCPT ); Wed, 6 Sep 2017 09:13:44 -0400 Received: from wuerfel.lan ([95.208.190.237]) by mrelayeu.kundenserver.de (mreue001 [212.227.15.129]) with ESMTPA (Nemesis) id 0MQZS8-1duyy923Qa-00Tjia; Wed, 06 Sep 2017 15:13:33 +0200 From: Arnd Bergmann To: Yannick Fertre , Philippe Cornu , Benjamin Gaignard , Vincent Abriou , David Airlie Cc: Arnd Bergmann , Archit Taneja , Neil Armstrong , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH] [RESEND] drm/stm: fix warning about multiplication in condition Date: Wed, 6 Sep 2017 15:13:07 +0200 Message-Id: <20170906131331.2691300-1-arnd@arndb.de> X-Mailer: git-send-email 2.9.0 X-Provags-ID: V03:K0:TEldHEBOH7XVzFkPWLlJi9TRbqy7+gsyHTCxGe/qlrKVxHfJfk9 1xcXk46YjZGY3ySOkB7w2vtrrimxW0bdk/W2LYswZZWdVJqLQ8UXmOz8ABW/A/+L8+hpq4O 4hn3J2PwG7okf6eP872S4PAtbCylGnPaqdfgLPb5nVLhCOld3bQtSyiVtx3iCljhUwI+Dz8 xE8xBEbVx1KTDiLcE1/aA== X-UI-Out-Filterresults: notjunk:1; V01:K0:hFErB3lZNTc=:8YY6bhE7k5uWQBKMCHyohf y22rRRmpeAdn4HWgVUhruN/buGtded5aNmbY01+qFmd2DOtJvKhbf7/TUdORUmJ48K0B7Bixm 2lxSuGBxwJRcpbzzn7UsB5XuanuC36Wg4fgL16rFBhf8M0k/xAyuA0YgdD1PizbkgH62f/Kh3 qsh2TK4AqQsETQuEk1vA7F17CBYmMclinG17H0Z3je1TEH/AgoDvF2yiC1EiIHn8tSXI+bmbY +/v0qT8Y3ZIHViuAxNYFpX3I48MbcUVjAYpcNLfnNWDMcVAoTLyEhE9P0eH9PDY9zPA5pKydw wT1zUtvBiiou/o8U/5pCF8RlbMpsW059q3H0niftOQ7en4RsSWgY/u3NFWTHz+UTMmF+gi/cE Pp1SdRms/vyBrhIze0FTwcHIs8hPalW/cybhInvlbzPI8tGGkXkfv/R/utMkGFKKDHfze10Rq 4pa5U1bDStf/imBhy8ht+bQ9ZJZeT5FAXCO4ScQkmxDmX3itwv/DF+33/ikuQ14NnDSNjZavq s5NOuoPGwSAL0Afz78M0lwlVp5MlOllMy7vE1Gd7YAq3ml2u46tzI9+6detssBQt15iBhVFgZ jXRG0BZ8p2u+8C+brUzU+abPBh7V8ATcd5EpXTpUL5XAGU1cYEIgigf6qIuPVfYoXCiY7niVz /9vR1sb0i/pkX1+u43HnFJ2bckQrt2Fy0Nmph3wgfZUhoXQRf/WElB8icrAfkZUi3a0OT25I7 4nR+/z6R8aJp34pPgxz44g0zW21m7oNt2jxAsA== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org gcc-7 complains about multiplying within a condition being suspicious: drivers/gpu/drm/stm/dw_mipi_dsi-stm.c: In function 'dsi_pll_get_clkout_khz': drivers/gpu/drm/stm/dw_mipi_dsi-stm.c:117:10: error: '*' in boolean context, suggest '&&' instead [-Werror=int-in-bool-context] The code here is correct, but can be easily rephrased to make that more obvious. I also swap out the error handling and the normal code path for clarity. Fixes: b0f09a3c69d9 ("drm/stm: Add STM32 DSI controller driver") Acked-by: Philippe Cornu Tested-by: Philippe Cornu Signed-off-by: Arnd Bergmann --- Originally sent on July 25, but never made it into linux-next. The warning is currently disabled in mainline, but this seems to be a legitimate instance, and we may want to turn it back on in the future. --- drivers/gpu/drm/stm/dw_mipi_dsi-stm.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) -- 2.9.0 diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c index 568c5d0461ea..e5b6310240fe 100644 --- a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c +++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c @@ -113,11 +113,13 @@ static enum dsi_color dsi_color_from_mipi(enum mipi_dsi_pixel_format fmt) static int dsi_pll_get_clkout_khz(int clkin_khz, int idf, int ndiv, int odf) { + int divisor = idf * odf; + /* prevent from division by 0 */ - if (idf * odf) - return DIV_ROUND_CLOSEST(clkin_khz * ndiv, idf * odf); + if (!divisor) + return 0; - return 0; + return DIV_ROUND_CLOSEST(clkin_khz * ndiv, divisor); } static int dsi_pll_get_params(int clkin_khz, int clkout_khz,