From patchwork Tue Jan 26 09:00:11 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Baruch Siach X-Patchwork-Id: 371362 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, 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 7E7C4C433E6 for ; Tue, 26 Jan 2021 09:03:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2CCAA230FC for ; Tue, 26 Jan 2021 09:03:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390744AbhAZJC4 (ORCPT ); Tue, 26 Jan 2021 04:02:56 -0500 Received: from guitar.tcltek.co.il ([192.115.133.116]:58133 "EHLO mx.tkos.co.il" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728030AbhAZJBd (ORCPT ); Tue, 26 Jan 2021 04:01:33 -0500 Received: from tarshish.tkos.co.il (unknown [10.0.8.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mx.tkos.co.il (Postfix) with ESMTPS id 03B4A4405AD; Tue, 26 Jan 2021 11:00:38 +0200 (IST) From: Baruch Siach To: stable@vger.kernel.org Cc: Baruch Siach , Russell King , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , Bartosz Golaszewski Subject: [PATCH 5.10-stable] gpio: mvebu: fix pwm .get_state period calculation Date: Tue, 26 Jan 2021 11:00:11 +0200 Message-Id: X-Mailer: git-send-email 2.29.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org commit e73b0101ae5124bf7cd3fb5d250302ad2f16a416 upstream. The period is the sum of on and off values. That is, calculate period as ($on + $off) / clkrate instead of $off / clkrate - $on / clkrate that makes no sense. Reported-by: Russell King Reviewed-by: Uwe Kleine-König Fixes: 757642f9a584e ("gpio: mvebu: Add limited PWM support") Signed-off-by: Baruch Siach Signed-off-by: Bartosz Golaszewski Reviewed-by: Uwe Kleine-König --- This backported patch applies to all kernels between 4.14 and 5.10 (inclusive). --- drivers/gpio/gpio-mvebu.c | 25 ++++++++++--------------- 1 file changed, 10 insertions(+), 15 deletions(-) diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c index 2f245594a90a..ed7c5fc47f52 100644 --- a/drivers/gpio/gpio-mvebu.c +++ b/drivers/gpio/gpio-mvebu.c @@ -660,9 +660,8 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip, spin_lock_irqsave(&mvpwm->lock, flags); - val = (unsigned long long) - readl_relaxed(mvebu_pwmreg_blink_on_duration(mvpwm)); - val *= NSEC_PER_SEC; + u = readl_relaxed(mvebu_pwmreg_blink_on_duration(mvpwm)); + val = (unsigned long long) u * NSEC_PER_SEC; do_div(val, mvpwm->clk_rate); if (val > UINT_MAX) state->duty_cycle = UINT_MAX; @@ -671,21 +670,17 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip, else state->duty_cycle = 1; - val = (unsigned long long) - readl_relaxed(mvebu_pwmreg_blink_off_duration(mvpwm)); + val = (unsigned long long) u; /* on duration */ + /* period = on + off duration */ + val += readl_relaxed(mvebu_pwmreg_blink_off_duration(mvpwm)); val *= NSEC_PER_SEC; do_div(val, mvpwm->clk_rate); - if (val < state->duty_cycle) { + if (val > UINT_MAX) + state->period = UINT_MAX; + else if (val) + state->period = val; + else state->period = 1; - } else { - val -= state->duty_cycle; - if (val > UINT_MAX) - state->period = UINT_MAX; - else if (val) - state->period = val; - else - state->period = 1; - } regmap_read(mvchip->regs, GPIO_BLINK_EN_OFF + mvchip->offset, &u); if (u)