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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 2C929C433FF for ; Mon, 29 Jul 2019 06:43:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0628D2075B for ; Mon, 29 Jul 2019 06:43:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726951AbfG2Gnk convert rfc822-to-8bit (ORCPT ); Mon, 29 Jul 2019 02:43:40 -0400 Received: from mail-ed1-f65.google.com ([209.85.208.65]:46603 "EHLO mail-ed1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726088AbfG2Gnj (ORCPT ); Mon, 29 Jul 2019 02:43:39 -0400 Received: by mail-ed1-f65.google.com with SMTP id d4so58318304edr.13; Sun, 28 Jul 2019 23:43:38 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=N3YcfI6Lt3N7Xfg/QsppatAiaJc9l2mfK7jxMUvJqWY=; b=ruNZ5YEUBG1D0cBfLarMvvTPCOfzNNKXypaliIhjwTzBAs1Rr3RR3XReoWXR3SubIh MtTwXxz2GK/waoekFOnXYASQPzOb7oO22PesxnksVL06DuWhu5YxiNVkW/aC1PEwZwD0 l2wxET4OQzELqOEkZpmtUBjWbse9ncHzmzr9k2hvcGPMQxipjbJKuTDOM501l0qqTHB/ vq1umPUpOAOw5Bkkj8Caexq/AmARqElWcg50cpLqU1+QpINNs8ohZZXjFm2io7Jm5Iph vwfaijClkYbtl5W++ATAWFKnIv1E4GP4iZjQsBS4Oqi2KYcVidiMel/XBG2of67bNjbv NQ3g== X-Gm-Message-State: APjAAAVxN7dlJF8qDGCQPuOaoUZqU4LyJkRWmhcm/SO9YMxjKVT+LLV6 GtDH2XCrK3GoPfhqwPh6yFmxENtGEnk= X-Google-Smtp-Source: APXvYqzFdJFRI/52u5fOHTiP8mLDcJ4ShMlNVqfK+Uef0oXPRqygtDeBly8v6e3OscHYonJ6nylk+Q== X-Received: by 2002:a17:906:3497:: with SMTP id g23mr83306443ejb.70.1564382617102; Sun, 28 Jul 2019 23:43:37 -0700 (PDT) Received: from mail-wr1-f50.google.com (mail-wr1-f50.google.com. [209.85.221.50]) by smtp.gmail.com with ESMTPSA id f36sm15796131ede.47.2019.07.28.23.43.36 (version=TLS1_3 cipher=AEAD-AES128-GCM-SHA256 bits=128/128); Sun, 28 Jul 2019 23:43:36 -0700 (PDT) Received: by mail-wr1-f50.google.com with SMTP id r1so60460548wrl.7; Sun, 28 Jul 2019 23:43:36 -0700 (PDT) X-Received: by 2002:adf:e941:: with SMTP id m1mr30982207wrn.279.1564382616355; Sun, 28 Jul 2019 23:43:36 -0700 (PDT) MIME-Version: 1.0 References: <20190726184045.14669-1-jernej.skrabec@siol.net> <20190726184045.14669-3-jernej.skrabec@siol.net> <20190729063630.rn325whatfnc3m7n@pengutronix.de> In-Reply-To: <20190729063630.rn325whatfnc3m7n@pengutronix.de> From: Chen-Yu Tsai Date: Mon, 29 Jul 2019 14:43:23 +0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 2/6] pwm: sun4i: Add a quirk for reset line To: =?UTF-8?Q?Uwe_Kleine=2DK=C3=B6nig?= Cc: Jernej Skrabec , Thierry Reding , Maxime Ripard , Rob Herring , Mark Rutland , linux-pwm@vger.kernel.org, devicetree , linux-arm-kernel , linux-kernel , linux-sunxi , Philipp Zabel Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 29, 2019 at 2:36 PM Uwe Kleine-König wrote: > > Cc += reset framework maintainer > > Hello Jernej, > > On Fri, Jul 26, 2019 at 08:40:41PM +0200, Jernej Skrabec wrote: > > H6 PWM core needs deasserted reset line in order to work. > > > > Add a quirk for it. > > > > Signed-off-by: Jernej Skrabec > > --- > > drivers/pwm/pwm-sun4i.c | 27 +++++++++++++++++++++++++-- > > 1 file changed, 25 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c > > index de78c824bbfd..1b7be8fbde86 100644 > > --- a/drivers/pwm/pwm-sun4i.c > > +++ b/drivers/pwm/pwm-sun4i.c > > @@ -16,6 +16,7 @@ > > #include > > #include > > #include > > +#include > > #include > > #include > > #include > > @@ -72,12 +73,14 @@ static const u32 prescaler_table[] = { > > > > struct sun4i_pwm_data { > > bool has_prescaler_bypass; > > + bool has_reset; > > unsigned int npwm; > > }; > > > > struct sun4i_pwm_chip { > > struct pwm_chip chip; > > struct clk *clk; > > + struct reset_control *rst; > > void __iomem *base; > > spinlock_t ctrl_lock; > > const struct sun4i_pwm_data *data; > > @@ -371,6 +374,14 @@ static int sun4i_pwm_probe(struct platform_device *pdev) > > if (IS_ERR(pwm->clk)) > > return PTR_ERR(pwm->clk); > > > > + if (pwm->data->has_reset) { > > + pwm->rst = devm_reset_control_get(&pdev->dev, NULL); > > + if (IS_ERR(pwm->rst)) > > + return PTR_ERR(pwm->rst); > > + > > + reset_control_deassert(pwm->rst); > > + } > > + > > I wonder why there is a need to track if a given chip needs a reset > line. I'd just use devm_reset_control_get_optional() and drop the > .has_reset member in struct sun4i_pwm_data. Because it's not optional for this platform, i.e. it won't work if the reset control (or clk, in the next patch) is somehow missing from the device tree. ChenYu > > pwm->chip.dev = &pdev->dev; > > pwm->chip.ops = &sun4i_pwm_ops; > > pwm->chip.base = -1; > > @@ -383,19 +394,31 @@ static int sun4i_pwm_probe(struct platform_device *pdev) > > ret = pwmchip_add(&pwm->chip); > > if (ret < 0) { > > dev_err(&pdev->dev, "failed to add PWM chip: %d\n", ret); > > - return ret; > > + goto err_pwm_add; > > } > > > > platform_set_drvdata(pdev, pwm); > > > > return 0; > > + > > +err_pwm_add: > > + reset_control_assert(pwm->rst); > > + > > + return ret; > > } > > > > static int sun4i_pwm_remove(struct platform_device *pdev) > > { > > struct sun4i_pwm_chip *pwm = platform_get_drvdata(pdev); > > + int ret; > > + > > + ret = pwmchip_remove(&pwm->chip); > > + if (ret) > > + return ret; > > > > - return pwmchip_remove(&pwm->chip); > > + reset_control_assert(pwm->rst); > > + > > + return 0; > > } > > > > static struct platform_driver sun4i_pwm_driver = { > > -- > Pengutronix e.K. | Uwe Kleine-König | > Industrial Linux Solutions | http://www.pengutronix.de/ |