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=-12.4 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,NICE_REPLY_A,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 02AD0C433E3 for ; Fri, 24 Jul 2020 15:27:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D1E15206E3 for ; Fri, 24 Jul 2020 15:27:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=broadcom.com header.i=@broadcom.com header.b="EVZTX8pd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726455AbgGXP1U (ORCPT ); Fri, 24 Jul 2020 11:27:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55964 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726411AbgGXP1U (ORCPT ); Fri, 24 Jul 2020 11:27:20 -0400 Received: from mail-wm1-x344.google.com (mail-wm1-x344.google.com [IPv6:2a00:1450:4864:20::344]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EDE8FC0619E4 for ; Fri, 24 Jul 2020 08:27:19 -0700 (PDT) Received: by mail-wm1-x344.google.com with SMTP id 184so8627003wmb.0 for ; Fri, 24 Jul 2020 08:27:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=btolEu+oBZ4e5G3BsfMzehyCFgYxasskNysgu6TkP7Y=; b=EVZTX8pdmQ7xRZx1Ep7GH7aaZzHEryY0gbe7OGRyxIVmLrW+13jSRkbeBY3YObc/fz GLVyOJuL6spgU5CenG8oa4r6PNC5tSXYyiliO3zFOLPLvCkkYMz3EtGcsheDycg7rsrg XGim9MKQNp37fNbDOqzZTaVav5Ydu+K1ZLXVc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=btolEu+oBZ4e5G3BsfMzehyCFgYxasskNysgu6TkP7Y=; b=MCHtZ9w1sYwKAj1VhkZEN7P/OcGJy61JkDuPh/snCMjSHko7ilw3+CJqVNsCFXTUwr LzX52TPrqtWaAEZnJVFK8tTexc9hhXVJg0gy8/MtLeggomseBATWSmpHTqIwc9YZXDeE q4IWJ0/nmJOh6opVU/w9pQB3y28/G4w7bw/htXhtXfdSiYxE4GYw6opLUYLfrmzaLFxT evsqS/vp9UIQnzDF2ryTnUYzJGp/9SHCPR4h1hT3QQGccs5Q4mUe51jgwsNd476PVMpe kQx7onBl942yAfcVLrIhKxe49hX/67CFzvntpnLpcDkfz3mW3pe5OXKxw2Hs1j1z3jCi PvxA== X-Gm-Message-State: AOAM5324Yd9MVOjhExaurBxVgrirT32atDfGizAYTVQwA2U2K3N+02Dy dw+zw02z7tIpSc1EE9fzw/2akw== X-Google-Smtp-Source: ABdhPJxmP6qLdy+uHYizxgbTFvILG+JdEPeE9P2WqStVt0R8TI+fyQFIT89R7AeGgp6PRKA01T3tgA== X-Received: by 2002:a05:600c:2907:: with SMTP id i7mr402360wmd.182.1595604438321; Fri, 24 Jul 2020 08:27:18 -0700 (PDT) Received: from [10.136.8.246] ([192.19.228.250]) by smtp.gmail.com with ESMTPSA id d18sm1647051wrj.8.2020.07.24.08.27.15 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 24 Jul 2020 08:27:17 -0700 (PDT) Subject: Re: [PATCH v4] pwm: bcm-iproc: handle clk_get_rate() return To: Scott Branden , Thierry Reding , Lee Jones Cc: =?UTF-8?Q?Uwe_Kleine-K=c3=b6nig?= , BCM Kernel Feedback , linux-pwm@vger.kernel.org, linux-kernel@vger.kernel.org, Rayagonda Kokatanur References: <20200718044606.18739-1-scott.branden@broadcom.com> From: Ray Jui Message-ID: <17848399-2b2d-b4f9-706b-94b3471c1e76@broadcom.com> Date: Fri, 24 Jul 2020 08:27:13 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200718044606.18739-1-scott.branden@broadcom.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-pwm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pwm@vger.kernel.org Hi Thierry/Uwe, Do you have any further comment on this patch? If not, could you please help to pick it up? Thanks, Ray On 7/17/2020 9:46 PM, Scott Branden wrote: > 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; >