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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 01D05C43334 for ; Mon, 13 Jun 2022 10:26:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244558AbiFMK0q (ORCPT ); Mon, 13 Jun 2022 06:26:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245417AbiFMKYj (ORCPT ); Mon, 13 Jun 2022 06:24:39 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ADF9BCE1E; Mon, 13 Jun 2022 03:19:00 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 437FC60AE7; Mon, 13 Jun 2022 10:19:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 554C7C34114; Mon, 13 Jun 2022 10:18:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655115539; bh=AQWhoYE5i3A/aRNfvTMVQ3y/FBcBv5MortRqr/HeOV0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=piMR/mMH8v09SofDcXkzsmaryyv7PFcDLoeY2Ex7tW2tDVkdSVuNpeEqTK7ZUWb7I KaQmZ2p6Etd3gPiSzpGixhkDFPCZyfO36myrQuwfMmEvPtSciUX+U+4ryA+XwpgIED YRnz4IqT2PF++90d5dQNAZfiHrqDdiMk/rEzAtXQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , Thierry Reding , Sasha Levin Subject: [PATCH 4.9 113/167] pwm: lp3943: Fix duty calculation in case period was clamped Date: Mon, 13 Jun 2022 12:09:47 +0200 Message-Id: <20220613094907.288759066@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220613094840.720778945@linuxfoundation.org> References: <20220613094840.720778945@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Uwe Kleine-König [ Upstream commit 5e3b07ca5cc78cd4a987e78446849e41288d87cb ] The hardware only supports periods <= 1.6 ms and if a bigger period is requested it is clamped to 1.6 ms. In this case duty_cycle might be bigger than 1.6 ms and then the duty cycle register is written with a value bigger than LP3943_MAX_DUTY. So clamp duty_cycle accordingly. Fixes: af66b3c0934e ("pwm: Add LP3943 PWM driver") Signed-off-by: Uwe Kleine-König Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin --- drivers/pwm/pwm-lp3943.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/pwm/pwm-lp3943.c b/drivers/pwm/pwm-lp3943.c index 872ea76a4f19..4612315687cd 100644 --- a/drivers/pwm/pwm-lp3943.c +++ b/drivers/pwm/pwm-lp3943.c @@ -128,6 +128,7 @@ static int lp3943_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, if (err) return err; + duty_ns = min(duty_ns, period_ns); val = (u8)(duty_ns * LP3943_MAX_DUTY / period_ns); return lp3943_write_byte(lp3943, reg_duty, val); -- 2.35.1