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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, 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 CE9DFC433DF for ; Fri, 17 Jul 2020 18:25:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A91F420759 for ; Fri, 17 Jul 2020 18:25:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=broadcom.com header.i=@broadcom.com header.b="NpK8ZB0b" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728088AbgGQSZ2 (ORCPT ); Fri, 17 Jul 2020 14:25:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52434 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726104AbgGQSZ1 (ORCPT ); Fri, 17 Jul 2020 14:25:27 -0400 Received: from mail-pg1-x544.google.com (mail-pg1-x544.google.com [IPv6:2607:f8b0:4864:20::544]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C99A9C0619D2 for ; Fri, 17 Jul 2020 11:25:27 -0700 (PDT) Received: by mail-pg1-x544.google.com with SMTP id m22so7054864pgv.9 for ; Fri, 17 Jul 2020 11:25:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; h=from:to:cc:subject:date:message-id; bh=gfp8TD0TK5ywr5xVIQqXt4UYUBwsLiLq5aLmh/fWgMc=; b=NpK8ZB0bdMbxWzl/pq5VT8a0z5qKaNdaPRH3iPx1izQuG7KZYGuCrOn0OChRrsqiBj NkTGh1GSEJ6LAqS6Kc82gI4caz6SMeMYuVQ8L9dOG5PC13mv2aKQCsu8jcR57u5f2VS/ xm6sLguFQeBqRolXBBSzNxA/YEcTdC6Qv9iUc= 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=gfp8TD0TK5ywr5xVIQqXt4UYUBwsLiLq5aLmh/fWgMc=; b=R4FkrwHJxP0WhnwqN+RnurtZDAEQgaLGu6wloYiDzJophzZSBI5sUcn2AUY/KISnH5 azKSqA8t6rg4mi3KrIefj/At8zsveBMqwabWZX/5Fo5NLqJgFlXspSvND/IO6HUcg7mC Tx4zFygYE5B2NWumBaUyEZXVsDVPW7SWpGPqFG6cfoUFsjmhvLdWsqunTvgnU6yxR7bh JJjYWeRnZV3DDF7oWnuwzRtLGszkDB9jUc0Vt1zCK+6QKNoS9cJHa7TfECZNJCk1rlFE Qd4Hst6+jcVJZJgDnAnx4UtQVJVgiTQsK3RkaKlBbcjngarv9IU0feBVcXhfpTI7yAvE a5Fg== X-Gm-Message-State: AOAM5316MqTu6iKs92D1oIAeLZxcSyJlNiV8eFvFbzZWGP8CIuEla48v WjzK/TK1bMd2U4phkNvGTDnEoA== X-Google-Smtp-Source: ABdhPJwZQAZQ+VC4KmggFqf57W1uimgfpchQ5C/usQb8ZksJ+7N3YyoL1HAWPxDbNvBojkwQlzbILQ== X-Received: by 2002:aa7:9e0e:: with SMTP id y14mr8590826pfq.77.1595010327276; Fri, 17 Jul 2020 11:25:27 -0700 (PDT) Received: from lbrmn-lnxub113.broadcom.net ([192.19.228.250]) by smtp.gmail.com with ESMTPSA id x8sm8374708pfn.61.2020.07.17.11.25.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 17 Jul 2020 11:25:26 -0700 (PDT) From: Scott Branden To: Thierry Reding , Lee Jones Cc: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , BCM Kernel Feedback , linux-pwm@vger.kernel.org, linux-kernel@vger.kernel.org, Rayagonda Kokatanur , Scott Branden Subject: [PATCH v2] pwm: bcm-iproc: handle clk_get_rate() return Date: Fri, 17 Jul 2020 11:25:12 -0700 Message-Id: <20200717182512.26001-1-scott.branden@broadcom.com> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rayagonda Kokatanur Handle clk_get_rate() returning <= 0 condition 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 --- Changes from v1: ensure 'polarity' and 'enabled' are populated when clk_get_rate is 0. --- 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 1f829edd8ee7..d392a828fc49 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; -- 2.17.1