From patchwork Mon May 31 04:46:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roman Beranek X-Patchwork-Id: 1485552 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-pwm-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=prusa3d-cz.20150623.gappssmtp.com header.i=@prusa3d-cz.20150623.gappssmtp.com header.a=rsa-sha256 header.s=20150623 header.b=oqizCzkW; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4FtjRt5qWfz9sVb for ; Mon, 31 May 2021 14:46:34 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230050AbhEaEsM (ORCPT ); Mon, 31 May 2021 00:48:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54658 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230024AbhEaEsK (ORCPT ); Mon, 31 May 2021 00:48:10 -0400 Received: from mail-ed1-x52b.google.com (mail-ed1-x52b.google.com [IPv6:2a00:1450:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9DD6AC061761 for ; Sun, 30 May 2021 21:46:22 -0700 (PDT) Received: by mail-ed1-x52b.google.com with SMTP id t3so11945640edc.7 for ; Sun, 30 May 2021 21:46:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=prusa3d-cz.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=bJxASN9/VJ7juNYNTX4EX6mmIGaWh5aMZc7qgtuD+IU=; b=oqizCzkWKvZf15jO987l874C6oFmf+PpZfdo0bF1dGwoCiPP+xMcyjRvMa6l7ELvc1 6Cbtz+m9iIJxpaZwVRMK6+ChJ3n5P7sgfdCJ/jvCwyJxa5JoKSRKP+nyWmLcGdlG9cub czyKvHvkeakh/Y25cl4sodc3AQjz4m9oADK5shjPcUtX7OEEwxWTAHX0l7aVfhiEjNoi Mzz2hA59kF31of4IpXdCBnxz0rEBbAkKAFByZVKuffbhNsS/3mk+J33vjT6hDC0WUpec IzCL42VsUCcNozdzaxSgNX7uruW2+PImiG08fYlJJYm6gYqfsmyA0ZXiMki29clDsvzY eftw== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=bJxASN9/VJ7juNYNTX4EX6mmIGaWh5aMZc7qgtuD+IU=; b=eC2Mp3yv5gExiWHFXjRcT6Lk2xnMuX/hkoxj6xETuEwi8LJSNgYGwvCBhVL7iXV0YI qFontzdgHANAEumwuJX3BL+x0M78Zmg3rT4R2oVOXXnsFTCmtt0QimH5918F0kZFgLSK haWbX8aXNuLs81rGIYOQaqZyuLFbEq7U+w0RkWDbvb8dp64pR28Hq+z3ifkSnJjcsV2Y atKBhD1elmDyLTDaIAS2FwiosfzKQP2c4T9+jHD20EyIOgpb2jQjLyKRbl8JUHYnO3Fq rvx+WXZKHS6khcXFy4I6hiTk5+Ii/GbCHMCAKP3L8W9Xa9V09l8RpmCbLyuU9G89S6Gv pziQ== X-Gm-Message-State: AOAM531gfyX8Ob4Xu/e4KEUlpf8YUB2eTMWY077ApTT21cEfwx/j0+1p mYxAf5SwW5ai4JsRRHpngYo6tA== X-Google-Smtp-Source: ABdhPJw2frB/ZmhM9tgloeFhP25YeHOi7cT5JP2v2UeqpuGbPnO2vr6JcP4Q185T9pvonWQGT/hPiA== X-Received: by 2002:aa7:cdd8:: with SMTP id h24mr23142258edw.276.1622436381298; Sun, 30 May 2021 21:46:21 -0700 (PDT) Received: from zen.local (ip-89-103-215-157.net.upcbroadband.cz. [89.103.215.157]) by smtp.gmail.com with ESMTPSA id h9sm6238376edt.18.2021.05.30.21.46.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 30 May 2021 21:46:20 -0700 (PDT) From: Roman Beranek X-Google-Original-From: Roman Beranek To: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= Cc: Thierry Reding , Emil Lenngren , Pascal Roeleven , Lee Jones , Maxime Ripard , Chen-Yu Tsai , linux-pwm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev, linux-sunxi@googlegroups.com Subject: [PATCH 4/6] pwm: sun4i: simplify calculation of the delay time Date: Mon, 31 May 2021 06:46:06 +0200 Message-Id: <20210531044608.1006024-5-roman.beranek@prusa3d.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210531044608.1006024-1-roman.beranek@prusa3d.com> References: <20210531044608.1006024-1-roman.beranek@prusa3d.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pwm@vger.kernel.org There's no reason to expect a single jiffy has passed since writing the CTRL register except if a preemption has occured in the meantime. Avoid introducing unnecessary complexity and simply wait for the whole period. Signed-off-by: Roman Beranek --- drivers/pwm/pwm-sun4i.c | 17 ++--------------- 1 file changed, 2 insertions(+), 15 deletions(-) diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c index b3ec59a83d00..8218173ce3f6 100644 --- a/drivers/pwm/pwm-sun4i.c +++ b/drivers/pwm/pwm-sun4i.c @@ -14,7 +14,6 @@ #include #include #include -#include #include #include #include @@ -89,7 +88,6 @@ struct sun4i_pwm_chip { void __iomem *base; struct mutex ctrl_lock; const struct sun4i_pwm_data *data; - unsigned long next_period[2]; }; static inline struct sun4i_pwm_chip *to_sun4i_pwm_chip(struct pwm_chip *chip) @@ -242,8 +240,7 @@ 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_us, prescaler = 0; - unsigned long now; + unsigned int prescaler = 0; bool bypass; pwm_get_state(pwm, &cstate); @@ -291,8 +288,6 @@ 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)); - sun4i_pwm->next_period[pwm->hwpwm] = jiffies + - nsecs_to_jiffies(cstate.period + 1000); if (state->polarity != PWM_POLARITY_NORMAL) ctrl &= ~BIT_CH(PWM_ACT_STATE, pwm->hwpwm); @@ -314,15 +309,7 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, } /* We need a full period to elapse before disabling the channel. */ - now = jiffies; - if (time_before(now, sun4i_pwm->next_period[pwm->hwpwm])) { - delay_us = jiffies_to_usecs(sun4i_pwm->next_period[pwm->hwpwm] - - now); - if ((delay_us / 500) > MAX_UDELAY_MS) - msleep(delay_us / 1000 + 1); - else - usleep_range(delay_us, delay_us * 2); - } + fsleep(cstate.period / NSEC_PER_USEC + 1); ctrl &= ~BIT_CH(PWM_CLK_GATING, pwm->hwpwm); sun4i_pwm_writel(sun4i_pwm, ctrl, PWM_CTRL_REG);