From patchwork Fri Jan 26 07:40:44 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nylon Chen X-Patchwork-Id: 13532158 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 578D1C47DDB for ; Fri, 26 Jan 2024 07:41:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=A8jcEXiI6wEX30UR4emYI0RKNMAbwHdVhNT98FdPWvw=; b=S+DThpFOpLsqpB 4S8dquaYaFz3QaCTJmpvcrCC8IUzMhfKoJV8N3ruy60uoMhkGAdl1/JROgTPOYvl8xL4Ob+1Tu0yk sbt5NC3hV2jOXorWPvDBttOao+Kr6xRXkwe1G1iRCbUjShrfmGuWTxsVIaoVgFfAAicEdwtHeYUmM hGx+jAQqLDUn7Ueb4MqNTz1rjI+jS8Q80UHLMYnYWH0Go3ypJH1fWuoGkwuQhcGnJ6/5PS1gQoHKW am2s3u+XNl8welF0uvwXeeBDQA9AID62DDfYKvZwnQbmWLVsJUz41x2sJH35Tm6L1t1N5RQej9mCX MT5I45NezyaRjd5y0p4A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rTGpn-00000003NQx-1lW5; Fri, 26 Jan 2024 07:41:07 +0000 Received: from mail-pg1-x52f.google.com ([2607:f8b0:4864:20::52f]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rTGpk-00000003NPe-2hvv for linux-riscv@lists.infradead.org; Fri, 26 Jan 2024 07:41:06 +0000 Received: by mail-pg1-x52f.google.com with SMTP id 41be03b00d2f7-53fa455cd94so36601a12.2 for ; Thu, 25 Jan 2024 23:41:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sifive.com; s=google; t=1706254862; x=1706859662; darn=lists.infradead.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=Oi7//kf+t5kQJparsU5zt0OUDO0vnQ4JFz56SbIPwWU=; b=YyAuYuu55mvCWZqIHspZ5Fgs0ojKP6HyQI75v9xX1VxIerx4jxCliyG88zCqlxa9my u/8ozSVII8TA5z8ERxqYSIB/1if7gQfq0GCUsCO6R5dkZIxpeMydJAGz/EPqkWHO19M+ jQP4rzxBKHdG4qLbJP85XwLwBaIJerL1xFH9QmP5r6zAdWHnSlaiiYHWYCEURWjyhb3q 3kG8lys7V89o9fcB0Twsyt49NGzlgRvJIt0Auaq3+6RL+1XcXaNt8UqRXUoPyN+gj52F tnYLHuZAyd8UDdQ0hz8qnugTpVjynBQ7guwBygaR+ZjJRLQpw+SfOIlXVLIH4NwFuwv/ S2ew== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1706254862; x=1706859662; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Oi7//kf+t5kQJparsU5zt0OUDO0vnQ4JFz56SbIPwWU=; b=H+jnI8nmZPevr5ysyKCsbCSCPcUUTkEUWWBmbApx+sb18p1pGONyJE2qi5ZU27caTo 3W+AKb1/6SPBGUBHFbr4SDYLjJ0nVJgbEo2I2Mxl9t1fC+/FErH4YfVPuMObecqlDs6B oOJtHyRw3jk2MeTSxrbe3iiN2fF3iTzwnb3lgy75qoNQj/3wiYRNKVtgMfZilcUPEAn8 Z70LnTizwH74/0kLwHpSbAR1A++1Qb0Hlxq/LSUvNmzRzA8+tAUeqlDbREpA5z9IAPzi tzpvTHeMTO3121gNKignBGKbgu4v0eDSLF7au2A/Onzz+PEosmAyl4V5U5SkvVyxjF/E okRg== X-Gm-Message-State: AOJu0YzgoxWNVfTi+z4148Wtg0Y5OYlazSOrXLtzk4r68ONNQpxvboXT iIX4QBbT1oCOkqG5dDZszZ4G/YeKypq4TR/b6FC906l/IvP5Ulv3QT/zApbkVXsYD6k/67lrtV2 P/Ntb16+3rTMvGP867lovn+V7BLAduJvU9pp/gDEG0ajUv5E/7FcXWng6T787C8aeUPdA6dLpxs 9n92CWWSy7tqQhvuRuVqGi4PHXtjgNMSdcFAFHCujGdNt2U5w+sgM= X-Google-Smtp-Source: AGHT+IGnJPsZk0zTW5jVAWvM0DbmXKrZKGcGHU2sO13aSc5h+P6v+oNIRQlSZxXzyeqqNKdMUs8odg== X-Received: by 2002:a17:903:2281:b0:1d7:297b:854f with SMTP id b1-20020a170903228100b001d7297b854fmr1540739plh.54.1706254861563; Thu, 25 Jan 2024 23:41:01 -0800 (PST) Received: from hsinchu15.internal.sifive.com (59-124-168-89.hinet-ip.hinet.net. [59.124.168.89]) by smtp.gmail.com with ESMTPSA id n3-20020a170902e54300b001d4816958c2sm521066plf.166.2024.01.25.23.40.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 25 Jan 2024 23:41:01 -0800 (PST) From: Nylon Chen To: linux-riscv@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pwm@vger.kernel.org, conor@kernel.org, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, palmer@dabbelt.com, paul.walmsley@sifive.com, aou@eecs.berkeley.edu, thierry.reding@gmail.com, u.kleine-koenig@pengutronix.de Cc: vincent.chen@sifive.com, zong.li@sifive.com, nylon.chen@sifive.com, nylon7717@gmail.com Subject: [PATCH v8 2/3] pwm: sifive: change the PWM controlled LED algorithm Date: Fri, 26 Jan 2024 15:40:44 +0800 Message-ID: <20240126074045.20159-3-nylon.chen@sifive.com> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20240126074045.20159-1-nylon.chen@sifive.com> References: <20240126074045.20159-1-nylon.chen@sifive.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240125_234104_733151_4A2BF06B X-CRM114-Status: GOOD ( 10.59 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org The `frac` variable represents the pulse inactive time, and the result of this algorithm is the pulse active time. Therefore, we must reverse the result. The reference is SiFive FU740-C000 Manual[0] Link: https://sifive.cdn.prismic.io/sifive/1a82e600-1f93-4f41-b2d8-86ed8b16acba_fu740-c000-manual-v1p6.pdf [0] Co-developed-by: Zong Li Signed-off-by: Zong Li Co-developed-by: Vincent Chen Signed-off-by: Vincent Chen Signed-off-by: Nylon Chen --- drivers/pwm/pwm-sifive.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/pwm/pwm-sifive.c b/drivers/pwm/pwm-sifive.c index eabddb7c7820..b07c8598bb21 100644 --- a/drivers/pwm/pwm-sifive.c +++ b/drivers/pwm/pwm-sifive.c @@ -113,6 +113,7 @@ static int pwm_sifive_get_state(struct pwm_chip *chip, struct pwm_device *pwm, u32 duty, val; duty = readl(ddata->regs + PWM_SIFIVE_PWMCMP(pwm->hwpwm)); + duty = (1U << PWM_SIFIVE_CMPWIDTH) - 1 - duty; state->enabled = duty > 0; @@ -123,11 +124,10 @@ static int pwm_sifive_get_state(struct pwm_chip *chip, struct pwm_device *pwm, state->period = ddata->real_period; state->duty_cycle = (u64)duty * ddata->real_period >> PWM_SIFIVE_CMPWIDTH; - state->polarity = PWM_POLARITY_INVERSED; + state->polarity = PWM_POLARITY_NORMAL; return 0; } - static int pwm_sifive_apply(struct pwm_chip *chip, struct pwm_device *pwm, const struct pwm_state *state) { @@ -139,7 +139,7 @@ static int pwm_sifive_apply(struct pwm_chip *chip, struct pwm_device *pwm, int ret = 0; u32 frac; - if (state->polarity != PWM_POLARITY_INVERSED) + if (state->polarity != PWM_POLARITY_NORMAL) return -EINVAL; cur_state = pwm->state; @@ -159,6 +159,7 @@ static int pwm_sifive_apply(struct pwm_chip *chip, struct pwm_device *pwm, frac = DIV64_U64_ROUND_CLOSEST(num, state->period); /* The hardware cannot generate a 100% duty cycle */ frac = min(frac, (1U << PWM_SIFIVE_CMPWIDTH) - 1); + frac = (1U << PWM_SIFIVE_CMPWIDTH) - 1 - frac; mutex_lock(&ddata->lock); if (state->period != ddata->approx_period) {