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=-8.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 DBD10C4360C for ; Fri, 4 Oct 2019 14:20:59 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 94DB52133F for ; Fri, 4 Oct 2019 14:20:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="brUTNGCy" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 94DB52133F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=LFyEB7p2n4tvNsNZSjMgtiN7GJTM7m5dfcqKd9Nm2TM=; b=brUTNGCylk3Oi7 xwa7ymn0eZhOT8NvijS+2FhfpkpQ7WNihGrusBpv4K4yywhe0LCPLnGaljrFBYT3Uo1A9NKm8xOQj +oRau6P9RseWAgsXIH2qGI4mLn/pvVIZsMXnew7PXSn/MyFp1dQs7QIpJz9zw7eBLTeK1reHCQN4Q kkysk6ethGcdNrrdZ+0zyyW/jIugMyh1HBsiZiA8tTIAIHElikmA41Lu3iiHh5TJjRECs4zbrJCZu YwAqcucOzUSVVhH5ra0CHRNY7NG3DwFTfWAMFwA7sa87h++4ekPAXC11H5z/qOjhBRe1UAG40Ketq v+SJ1OKowDa9n4aeD+bg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1iGORy-0002iV-Nz; Fri, 04 Oct 2019 14:20:54 +0000 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.92.2 #3 (Red Hat Linux)) id 1iGORl-0002XS-Cl for linux-arm-kernel@lists.infradead.org; Fri, 04 Oct 2019 14:20:43 +0000 Received: from pty.hi.pengutronix.de ([2001:67c:670:100:1d::c5]) by metis.ext.pengutronix.de with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1iGORh-0008UR-Aw; Fri, 04 Oct 2019 16:20:37 +0200 Received: from ukl by pty.hi.pengutronix.de with local (Exim 4.89) (envelope-from ) id 1iGORg-0004n2-VN; Fri, 04 Oct 2019 16:20:36 +0200 Date: Fri, 4 Oct 2019 16:20:36 +0200 From: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= To: Rasmus Villemoes Subject: Re: [PATCH v2 3/6] pwm: mxs: add support for inverse polarity Message-ID: <20191004142036.apzjf54dlzfah5xl@pengutronix.de> References: <20191004133207.6663-1-linux@rasmusvillemoes.dk> <20191004133207.6663-4-linux@rasmusvillemoes.dk> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20191004133207.6663-4-linux@rasmusvillemoes.dk> User-Agent: NeoMutt/20170113 (1.7.2) X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c5 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-arm-kernel@lists.infradead.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191004_072041_464345_18138667 X-CRM114-Status: GOOD ( 18.23 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, linux-pwm@vger.kernel.org, Shawn Guo , Sascha Hauer , linux-kernel@vger.kernel.org, Rob Herring , Thierry Reding , NXP Linux Team , Pengutronix Kernel Team , Fabio Estevam , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Oct 04, 2019 at 03:32:04PM +0200, Rasmus Villemoes wrote: > If I'm reading of_pwm_xlate_with_flags() right, existing device trees > that set #pwm-cells =3D 2 will continue to work. Yes, that's what I expect, too. > Signed-off-by: Rasmus Villemoes > --- > drivers/pwm/pwm-mxs.c | 14 ++++++++++---- > 1 file changed, 10 insertions(+), 4 deletions(-) > = > diff --git a/drivers/pwm/pwm-mxs.c b/drivers/pwm/pwm-mxs.c > index 5a6835e18fc6..57562221c439 100644 > --- a/drivers/pwm/pwm-mxs.c > +++ b/drivers/pwm/pwm-mxs.c > @@ -25,8 +25,11 @@ > #define PERIOD_PERIOD(p) ((p) & 0xffff) > #define PERIOD_PERIOD_MAX 0x10000 > #define PERIOD_ACTIVE_HIGH (3 << 16) > +#define PERIOD_ACTIVE_LOW (2 << 16) > +#define PERIOD_INACTIVE_HIGH (3 << 18) > #define PERIOD_INACTIVE_LOW (2 << 18) > #define PERIOD_POLARITY_NORMAL (PERIOD_ACTIVE_HIGH | PERIOD_INACTIVE_LO= W) > +#define PERIOD_POLARITY_INVERSE (PERIOD_ACTIVE_LOW | PERIOD_INACTIVE_HI= GH) > #define PERIOD_CDIV(div) (((div) & 0x7) << 20) > #define PERIOD_CDIV_MAX 8 > = > @@ -50,9 +53,7 @@ static int mxs_pwm_apply(struct pwm_chip *chip, struct = pwm_device *pwm, > unsigned int period_cycles, duty_cycles; > unsigned long rate; > unsigned long long c; > - > - if (state->polarity !=3D PWM_POLARITY_NORMAL) > - return -ENOTSUPP; > + unsigned int pol_bits; > = > /* > * If the PWM channel is disabled, make sure to turn on the > @@ -91,9 +92,12 @@ static int mxs_pwm_apply(struct pwm_chip *chip, struct= pwm_device *pwm, > * only take effect at the beginning of a new period, avoiding > * glitches. > */ > + > + pol_bits =3D state->polarity =3D=3D PWM_POLARITY_NORMAL ? > + PERIOD_POLARITY_NORMAL : PERIOD_POLARITY_INVERSE; > writel(duty_cycles << 16, > mxs->base + PWM_ACTIVE0 + pwm->hwpwm * 0x20); > - writel(PERIOD_PERIOD(period_cycles) | PERIOD_POLARITY_NORMAL | PERIOD_C= DIV(div), > + writel(PERIOD_PERIOD(period_cycles) | pol_bits | PERIOD_CDIV(div), > mxs->base + PWM_PERIOD0 + pwm->hwpwm * 0x20); Is the avoidance of glitches still true when period changes? I assume that yes, but I wonder if you tested that. Best regards Uwe -- = Pengutronix e.K. | Uwe Kleine-K=F6nig | Industrial Linux Solutions | http://www.pengutronix.de/ | _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel