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 E4C1FC433E0 for ; Sat, 18 Jul 2020 04:46:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8AE8B2076D for ; Sat, 18 Jul 2020 04:46:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=broadcom.com header.i=@broadcom.com header.b="bY/0au6W" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726520AbgGREqV (ORCPT ); Sat, 18 Jul 2020 00:46:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34670 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726226AbgGREqV (ORCPT ); Sat, 18 Jul 2020 00:46:21 -0400 Received: from mail-ej1-x641.google.com (mail-ej1-x641.google.com [IPv6:2a00:1450:4864:20::641]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 990C8C0619D3 for ; Fri, 17 Jul 2020 21:46:20 -0700 (PDT) Received: by mail-ej1-x641.google.com with SMTP id f12so12980201eja.9 for ; Fri, 17 Jul 2020 21:46:20 -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=6XtgaMcVkuKZN6Vqx9za29ZMiqRwMaKdWv8eAb+N9vg=; b=bY/0au6WAL+u8vh4fua/qFVLuU47TL1PTMEtiMXHJM49ItyD0NffJ8wZiiwrOGWaTD eBswM0qBkTmIt+JunE0pptyKPWhBHOu+L7miR1ny6lkFWsjiMicvX/VTfHfxfO7Afb7r b4wYNVuoxS+gyaOXlmDxE90qT2T3znv3d3m14= 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=6XtgaMcVkuKZN6Vqx9za29ZMiqRwMaKdWv8eAb+N9vg=; b=rtitRXzYN/CLkAL2f/0VzwX86j7H2c5EKk6I2IZRJF8eJT72AQS/jx+h+E3Za+BxyB M13xjK/1c0yWz70umeI1oIWu5i9p8mAebJNGzBDd89MYF6iBmSIN6kq2e/fQyML8+B3F QLKdp5b84bYpojI94ylAH7T/d46rhTslwpXDoTyf0Jm+jL0NEuTteABfJSD8zD+SOZPc yVCpqd9X7/bPE61wrjV6zlF/QShLSlXQdKmQ1LAgddCboQDFoiNHCAZtlFnfusZzpook buCC6qNPy9uVIJFv7PjwkOWWkSBbSsZX4Rl+5hpfK/PGwVTx/lfKS92XhWXNI2eHTHZE GqXQ== X-Gm-Message-State: AOAM533ZPs0bXMCHyQd/bTEXkPtS8yjJln7XYS3UJukc4CaZZcPcn1DX tqhxR5ecGniibtctmVKlK2lP4A== X-Google-Smtp-Source: ABdhPJy1oAFtDdH08tlydsMUGH/N2FrHzxaMP3ualaq1GVbB+RmhdCMIkpJOIZUQjDN/KFBT7tG6vw== X-Received: by 2002:a17:906:3945:: with SMTP id g5mr12271263eje.549.1595047579113; Fri, 17 Jul 2020 21:46:19 -0700 (PDT) Received: from lbrmn-lnxub113.broadcom.net ([192.19.228.250]) by smtp.gmail.com with ESMTPSA id u13sm9680553ejx.3.2020.07.17.21.46.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 17 Jul 2020 21:46:18 -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 v4] pwm: bcm-iproc: handle clk_get_rate() return Date: Fri, 17 Jul 2020 21:46:06 -0700 Message-Id: <20200718044606.18739-1-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 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 --- Changes from v3: fixed typo in commit message: Reviewed-off-by. Hopefully everything clean now. Changes from v2: update commit message to remove <= condition as clk_get_rate only returns value >= 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