From patchwork Thu Aug 20 09:23:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 265626 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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 88217C433DF for ; Thu, 20 Aug 2020 10:47:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 692472075E for ; Thu, 20 Aug 2020 10:47:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597920479; bh=Q9Nk+Ip/pL2MI3WbOFTTcfDsLTucVvUTK6hNb3XVb9U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=zv7YDqIYFxH5LUhhkPyq6hg5ocSGozyPMFIcMVFXoMlxh9iS06ZdM8EuRzqy5ymVv rY7K0KuWydbdUxm/ahI4dKJlkmqpBBHETNiRdcf34WoRGfS879JXo5eJvMaY87/lvN g0Lzz4RDY4x54y6bsi3qY9n7YhSv/Z2Nyg0XwSrA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731389AbgHTKr4 (ORCPT ); Thu, 20 Aug 2020 06:47:56 -0400 Received: from mail.kernel.org ([198.145.29.99]:35146 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726974AbgHTKPk (ORCPT ); Thu, 20 Aug 2020 06:15:40 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E03432067C; Thu, 20 Aug 2020 10:15:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597918539; bh=Q9Nk+Ip/pL2MI3WbOFTTcfDsLTucVvUTK6hNb3XVb9U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=k2nSlfP09B0pAXIyy6Xe/3gJLXFsZVAL+GLrkhWY9oy+lqiWfjflaHzQcC3MK8d1e 94guKUXUU4lI+eAdV4phuNdokPoo4+RY+0T/OoGyPS12Pl/5ktV+woN11BV3GIXSvE ly1FckeOOJDedqxlpaxzl2Ufmj7mu8hY6xS/pbKo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Rayagonda Kokatanur , Scott Branden , Ray Jui , =?utf-8?q?Uwe_Kleine-K=C3=B6ni?= =?utf-8?q?g?= , Thierry Reding , Sasha Levin Subject: [PATCH 4.14 206/228] pwm: bcm-iproc: handle clk_get_rate() return Date: Thu, 20 Aug 2020 11:23:01 +0200 Message-Id: <20200820091617.829943197@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200820091607.532711107@linuxfoundation.org> References: <20200820091607.532711107@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Rayagonda Kokatanur [ Upstream commit 6ced5ff0be8e94871ba846dfbddf69d21363f3d7 ] Handle clk_get_rate() returning 0 to avoid possible division by zero. Fixes: daa5abc41c80 ("pwm: Add support for Broadcom iProc PWM controller") Signed-off-by: Rayagonda Kokatanur Signed-off-by: Scott Branden Reviewed-by: Ray Jui Reviewed-by: Uwe Kleine-König Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin --- drivers/pwm/pwm-bcm-iproc.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/pwm/pwm-bcm-iproc.c b/drivers/pwm/pwm-bcm-iproc.c index 31b01035d0ab3..8cfba3614e601 100644 --- a/drivers/pwm/pwm-bcm-iproc.c +++ b/drivers/pwm/pwm-bcm-iproc.c @@ -85,8 +85,6 @@ static void iproc_pwmc_get_state(struct pwm_chip *chip, struct pwm_device *pwm, u64 tmp, multi, rate; u32 value, prescale; - rate = clk_get_rate(ip->clk); - value = readl(ip->base + IPROC_PWM_CTRL_OFFSET); if (value & BIT(IPROC_PWM_CTRL_EN_SHIFT(pwm->hwpwm))) @@ -99,6 +97,13 @@ static void iproc_pwmc_get_state(struct pwm_chip *chip, struct pwm_device *pwm, else state->polarity = PWM_POLARITY_INVERSED; + rate = clk_get_rate(ip->clk); + if (rate == 0) { + state->period = 0; + state->duty_cycle = 0; + return; + } + value = readl(ip->base + IPROC_PWM_PRESCALE_OFFSET); prescale = value >> IPROC_PWM_PRESCALE_SHIFT(pwm->hwpwm); prescale &= IPROC_PWM_PRESCALE_MAX;