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 AA15AC4332F for ; Tue, 25 Jan 2022 12:38:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1383663AbiAYMiw (ORCPT ); Tue, 25 Jan 2022 07:38:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39386 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1383355AbiAYMel (ORCPT ); Tue, 25 Jan 2022 07:34:41 -0500 Received: from mail-wr1-x42c.google.com (mail-wr1-x42c.google.com [IPv6:2a00:1450:4864:20::42c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EB15BC06176A; Tue, 25 Jan 2022 04:34:40 -0800 (PST) Received: by mail-wr1-x42c.google.com with SMTP id s9so3780342wrb.6; Tue, 25 Jan 2022 04:34:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=6OAWPEyWDr+7hDA+9CSD9lvGUK7uqcFht/9bAYyx1tI=; b=GJ2iBuMMg3rc7pKhvRcmfe66yvZQHpb2iu2SlxeGm+GpdYkOH0ngQicdG7sDB6ituq CC3hE9sykx63yWoOoabfqueA43EsAJeUgWndaHgtXpmOQ+gfuM+/aR/Es1sKPSCcS9Az zekiaJlHncAODU6gkJHyOCU94DiaOEwD70CVrecmqlQeEK2L/Rw+GToG4V1px+xMXLXE pEC/4MprKsABarW0xRMJGcD7de2WfT3fKTRQIZFac8IY1JixACIkpsKl8r3dYdQ15EZZ kN8P4P2gTNE0tydyMNFvsmkDZn6mOlUZU/UUA+rJHA7B+l1TZ/J/RNdacys9cSqOA96K Quxg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=6OAWPEyWDr+7hDA+9CSD9lvGUK7uqcFht/9bAYyx1tI=; b=0a8mxCdgLIGrB14Vv0GZICE6s010DR0kEr2G2hxBs0XUCzynICDd33TBPbMOh/qotj zESy5rR6QR4tnXacccoijtCD73qCoRsBnF/1ukg0AP+4K/vXDTGQqcN6kzca6jVg/dY3 ooI8G2JgpUayg6J2hVXNwC7GeVXLHEjx7H8mtuhzQbum3+5bG/HnNRqy+VoIcDgQXvED wadwZwbY2dNBzNOaYx1GZsLXFpURkEQplq9HdhxvC9qmzRG73jW+hzP03JmLMAu2snRS wbdEN75dqSiWb93IHf5oeb6bZDR+hqHfahTxfLiyfvC7oRUlClTuU5+iIaw5bs3WDPA4 8JEA== X-Gm-Message-State: AOAM533fikDsFQ4Yav1pX4ZHltEt91xOEKXoJHP5Slsbgr2C8SX7hqcs lRsy0nYPe81XQX92I4XZ8g+tHZSUDjw= X-Google-Smtp-Source: ABdhPJzQnr6JeOKYIbhvf7bj5FHd7nmYtpQUpiJm+mK6YbPElOShBgup9CrHNvL+zowsK10siQLiqg== X-Received: by 2002:adf:dfd0:: with SMTP id q16mr18676146wrn.131.1643114079572; Tue, 25 Jan 2022 04:34:39 -0800 (PST) Received: from heron.intern.cm-ag (p200300dc6f046a000000000000000fd2.dip0.t-ipconnect.de. [2003:dc:6f04:6a00::fd2]) by smtp.gmail.com with ESMTPSA id e10sm1558633wrq.53.2022.01.25.04.34.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Jan 2022 04:34:39 -0800 (PST) From: Max Kellermann To: linux-pwm@vger.kernel.org, thierry.reding@gmail.com, u.kleine-koenig@pengutronix.de, lee.jones@linaro.org Cc: linux-kernel@vger.kernel.org, andrey@lebedev.lt, Max Kellermann , stable@vger.kernel.org Subject: [PATCH 2/3] pwm-sun4i: calculate "delay_jiffies" directly, eliminate absolute time Date: Tue, 25 Jan 2022 13:34:28 +0100 Message-Id: <20220125123429.3490883-2-max.kellermann@gmail.com> X-Mailer: git-send-email 2.34.0 In-Reply-To: <20220125123429.3490883-1-max.kellermann@gmail.com> References: <20220125123429.3490883-1-max.kellermann@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-pwm@vger.kernel.org Basically this code did "jiffies + period - jiffies", and we can simply eliminate the "jiffies" time stamp here. Cc: stable@vger.kernel.org Signed-off-by: Max Kellermann --- drivers/pwm/pwm-sun4i.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c index c7c564a6bf36..b44deececb8b 100644 --- a/drivers/pwm/pwm-sun4i.c +++ b/drivers/pwm/pwm-sun4i.c @@ -234,9 +234,8 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, struct pwm_state cstate; u32 ctrl, duty = 0, period = 0, val; int ret; + unsigned int delay_jiffies; unsigned int delay_us, prescaler = 0; - unsigned long now; - unsigned long next_period; bool bypass; pwm_get_state(pwm, &cstate); @@ -284,8 +283,6 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, val = (duty & PWM_DTY_MASK) | PWM_PRD(period); sun4i_pwm_writel(sun4i_pwm, val, PWM_CH_PRD(pwm->hwpwm)); - next_period = jiffies + - nsecs_to_jiffies(cstate.period + 1000); if (state->polarity != PWM_POLARITY_NORMAL) ctrl &= ~BIT_CH(PWM_ACT_STATE, pwm->hwpwm); @@ -305,14 +302,12 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, return 0; /* We need a full period to elapse before disabling the channel. */ - now = jiffies; - if (time_before(now, next_period)) { - delay_us = jiffies_to_usecs(next_period - now); - if ((delay_us / 500) > MAX_UDELAY_MS) - msleep(delay_us / 1000 + 1); - else - usleep_range(delay_us, delay_us * 2); - } + delay_jiffies = nsecs_to_jiffies(cstate.period + 1000); + delay_us = jiffies_to_usecs(delay_jiffies); + if ((delay_us / 500) > MAX_UDELAY_MS) + msleep(delay_us / 1000 + 1); + else + usleep_range(delay_us, delay_us * 2); spin_lock(&sun4i_pwm->ctrl_lock); ctrl = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG); -- 2.34.0