From patchwork Thu Apr 20 09:34:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nylon Chen X-Patchwork-Id: 85818 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp204994vqo; Thu, 20 Apr 2023 02:45:57 -0700 (PDT) X-Google-Smtp-Source: AKy350bpKRfNKvAIGDGRcwcXevoF/iLw6K8zjRgHifv54tQvmtcLC301+6Iq8DC337Nx1FY0Bond X-Received: by 2002:a05:6a21:338c:b0:f0:c858:2d68 with SMTP id yy12-20020a056a21338c00b000f0c8582d68mr1626298pzb.35.1681983956851; Thu, 20 Apr 2023 02:45:56 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1681983956; cv=none; d=google.com; s=arc-20160816; b=S5hIw/aF+7dJkEsANOK1M1IojvE4Z/6Y/vrVaOYGPVTwaa8awEmGvQZA0G3X5Q4r82 tfYfacEbL8w1tQ0nXJEfCjB0ru1xuRZxap18tDGyA+5UKdH4NA6w1F7f7t1PjnirWITV xkh1ZajT3xT/cqHyANI44873ktufKppa+K+/MoeaVvCa+NzGSeUWxDALf3jaHLWcINSm rt3sSr8Nu6H6LL0Qj4HxcVUxPm9/lATmNbrJPmtdwGe69G8cQg/6GTNHV7i/WIx1YfwB j13Jkxvmoc8plqhJexHZjpako0VVvNa6kGOxYbIUYk/ks3kPhlrEoiZWTVZWOXjPMtbr 4HCQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=Ryva+FQmb09SgOiCE7P4pQBiT6BdeSdh3y4Qn91oZ9M=; b=x9IUPrxHG76YKh5qea+qRBM3KXwFtXcM1g6tajH1sJI9LVRFyKX3RS2fLV47qKVKCu nk7hpZAFtQiy8b/6Ef1ITzWJxUtDGLiPjOlKy1zPn4ZUFAX23JkEfcq0ZAWGzBgtuV3m Udahhyk3D+RQ9NOTadPCgB6hZh1rErTvMuJDdZdwK5fxELSviHPNw6VReFrazBdvvIfx uPHham05+xot6ebDXQUNBAEKfpRcaIHph6oyI+NlhiqwWTP95w432TPYHBJfAYiUVgOi e9IlGkWpsC+nS5kQaDj7mOe5lfkudGQ6wn9UJOMQSq+npsL1d2bCPDYJl5A2ijnv2omw y/Uw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@sifive.com header.s=google header.b=d4ER6huQ; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=sifive.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id h186-20020a636cc3000000b0051b554df1besi1068694pgc.840.2023.04.20.02.45.40; Thu, 20 Apr 2023 02:45:56 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@sifive.com header.s=google header.b=d4ER6huQ; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=sifive.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234125AbjDTJfn (ORCPT + 99 others); Thu, 20 Apr 2023 05:35:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50048 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234261AbjDTJfQ (ORCPT ); Thu, 20 Apr 2023 05:35:16 -0400 Received: from mail-pg1-x533.google.com (mail-pg1-x533.google.com [IPv6:2607:f8b0:4864:20::533]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 672722D5A for ; Thu, 20 Apr 2023 02:35:14 -0700 (PDT) Received: by mail-pg1-x533.google.com with SMTP id 41be03b00d2f7-5144043d9d1so579401a12.3 for ; Thu, 20 Apr 2023 02:35:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sifive.com; s=google; t=1681983314; x=1684575314; 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=Ryva+FQmb09SgOiCE7P4pQBiT6BdeSdh3y4Qn91oZ9M=; b=d4ER6huQjMtUV4wHdMb9ME9KpU3d2FGtvqsgiDTUlUyLvDePcXJ0PKh98S6NEnsa2G XpQA1rCPbkz2/bCmmRIw/iKSY7Jc/iG598aSV3OIGqyeUx4IBcGUZKtO4vIBwSqT9r0P p5FSKMM0VYyfyGjMat2EmIyNNAimvy6yE8WNCYrKGxEhDc/YAWf+Pc70ybdNvL8zO+JA QpNju3Pf0hJEFC4gFdxrSa9X6mz6r/WWX5OMVqulCgrYK2qAWDlWa525eBQUcoKAVN9a K70k1rCm/C/aU30qmXDSBl7EG/LeuOhixKwJILpFQprjgRGLNArBduUmQD/Zx6K1YSUy l2Eg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681983314; x=1684575314; 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=Ryva+FQmb09SgOiCE7P4pQBiT6BdeSdh3y4Qn91oZ9M=; b=ASuFW4UE6ex0l5cIowIvDm8gh8ccNsRAT6exORwywLDLucjrL9xuOuD5oJaITaxnXB dT/q1Eyn1H29JYIGsAFAiTxRuxVXbJYp899e7OmhPEpISrDyLXZ52hEcgAjCj8cpVzMF vi2cQfnJEqE8Hg9y7EJ95K8q0KYccVKJSrRrEFpFG1znVQfBIkMjIiy8a8ekJYtXPZtw F1KlRT1LNjaWAt3fPg1XGEJNA3AuIKSqtZ6BsZDIM82Qvk7idHjxX3ONgHr36EeTIJBY qlXJz54b/t4qe2t3mhnls7E7SJDo8gV8syRqoE8qUqP0oyTf2XchYM+6ourQwNpLCY/1 PDxA== X-Gm-Message-State: AAQBX9duMGPl2pJWdO9GzQExfKytt+JZFQmTyVoDVxBuj5wdjwVrRkc4 Oc/tnh0dmBmPaZIgzkr70+TNrg== X-Received: by 2002:a17:90b:10c:b0:23f:9fac:6b35 with SMTP id p12-20020a17090b010c00b0023f9fac6b35mr1017558pjz.39.1681983313820; Thu, 20 Apr 2023 02:35:13 -0700 (PDT) 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 p5-20020a63c145000000b0051ba9d772f9sm781551pgi.59.2023.04.20.02.35.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 20 Apr 2023 02:35:13 -0700 (PDT) From: Nylon Chen To: aou@eecs.berkeley.edu, conor@kernel.org, emil.renner.berthing@canonical.com, geert+renesas@glider.be, heiko@sntech.de, krzysztof.kozlowski+dt@linaro.org, palmer@dabbelt.com, paul.walmsley@sifive.com, robh+dt@kernel.org, thierry.reding@gmail.com, u.kleine-koenig@pengutronix.de, devicetree@vger.kernel.org, linux-pwm@vger.kernel.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Cc: nylon.chen@sifive.com, nylon7717@gmail.com, zong.li@sifive.com, greentime.hu@sifive.com, vincent.chen@sifive.com, Conor Dooley Subject: [PATCH v3 2/2] pwm: sifive: change the PWM controlled LED algorithm Date: Thu, 20 Apr 2023 17:34:57 +0800 Message-Id: <20230420093457.18936-3-nylon.chen@sifive.com> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230420093457.18936-1-nylon.chen@sifive.com> References: <20230420093457.18936-1-nylon.chen@sifive.com> MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1763688009176973314?= X-GMAIL-MSGID: =?utf-8?q?1763688009176973314?= 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] Acked-by: Conor Dooley Reviewed-by: Conor Dooley Signed-off-by: Nylon Chen Signed-off-by: Vincent Chen --- drivers/pwm/pwm-sifive.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/pwm/pwm-sifive.c b/drivers/pwm/pwm-sifive.c index 393a4b97fc19..d5d5f36da297 100644 --- a/drivers/pwm/pwm-sifive.c +++ b/drivers/pwm/pwm-sifive.c @@ -132,13 +132,13 @@ static int pwm_sifive_apply(struct pwm_chip *chip, struct pwm_device *pwm, { struct pwm_sifive_ddata *ddata = pwm_sifive_chip_to_ddata(chip); struct pwm_state cur_state; - unsigned int duty_cycle; + unsigned int duty_cycle, period; unsigned long long num; bool enabled; int ret = 0; u32 frac; - if (state->polarity != PWM_POLARITY_INVERSED) + if (state->polarity != PWM_POLARITY_NORMAL && state->polarity != PWM_POLARITY_INVERSED) return -EINVAL; cur_state = pwm->state; @@ -154,10 +154,13 @@ static int pwm_sifive_apply(struct pwm_chip *chip, struct pwm_device *pwm, * calculating the register values first and then writing them * consecutively */ + period = max(state->period, ddata->approx_period); num = (u64)duty_cycle * (1U << PWM_SIFIVE_CMPWIDTH); frac = DIV64_U64_ROUND_CLOSEST(num, state->period); - /* The hardware cannot generate a 100% duty cycle */ frac = min(frac, (1U << PWM_SIFIVE_CMPWIDTH) - 1); + /* The hardware cannot generate a 100% duty cycle */ + frac = (1U << PWM_SIFIVE_CMPWIDTH) - 1 - frac; + mutex_lock(&ddata->lock); if (state->period != ddata->approx_period) {