From patchwork Tue Aug 28 13:01:22 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Claudiu Beznea X-Patchwork-Id: 10578423 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 915FA5A4 for ; Tue, 28 Aug 2018 13:06:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 80EB72A14A for ; Tue, 28 Aug 2018 13:06:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 751332A1C5; Tue, 28 Aug 2018 13:06:21 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id C83A72A14A for ; Tue, 28 Aug 2018 13:06:20 +0000 (UTC) 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:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=O43o61bPVRey2kAruINcVpgWsT0lNKifiYBQHwjaPOo=; b=nCyDha0euV+DTn wCR16jKTzH43igIlVNyqDshrXxley4zC6OBT76Xg0JGRKrpU8VxDij/igZbNN+Xzy99swovdDL9+7 WezZQW6XKIet1AsDIlkL9dqvSjDJzzbiFwMmzJTvkKZRvnmL4fBaXGUN5miIDrwNrm2uLnbcqSU2j Wg078EqQcGQgruYhj0TmrtTdFd9VkPiFzo4/AL58UEdkUuhaEv1OHiNxSZ+VLjuk/FsoqPzzRiAvR iLgUHvGNqopB1OMQooJ3eMbA25oGRu+nAXF9yAT70VPgA+nd8IKfjjwusJtIvujTgD2DVTPC5W8Y2 DfrAHcm8pyI5o3J1wmqQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1fudh4-0005DI-U1; Tue, 28 Aug 2018 13:06:03 +0000 Received: from esa5.microchip.iphmx.com ([216.71.150.166]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1fuddF-0002PW-PP for linux-arm-kernel@lists.infradead.org; Tue, 28 Aug 2018 13:02:12 +0000 X-IronPort-AV: E=Sophos;i="5.53,299,1531810800"; d="scan'208";a="16756381" Received: from smtpout.microchip.com (HELO email.microchip.com) ([198.175.253.82]) by esa5.microchip.iphmx.com with ESMTP/TLS/DHE-RSA-AES256-SHA; 28 Aug 2018 06:01:59 -0700 Received: from m18063-ThinkPad-T460p.mchp-main.com (10.10.76.4) by chn-sv-exch04.mchp-main.com (10.10.76.105) with Microsoft SMTP Server id 14.3.352.0; Tue, 28 Aug 2018 06:01:58 -0700 From: Claudiu Beznea To: , , , , , , Subject: [RESEND PATCH v5 5/9] pwm: add PWM modes Date: Tue, 28 Aug 2018 16:01:22 +0300 Message-ID: <1535461286-12308-6-git-send-email-claudiu.beznea@microchip.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1535461286-12308-1-git-send-email-claudiu.beznea@microchip.com> References: <1535461286-12308-1-git-send-email-claudiu.beznea@microchip.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20180828_060206_055239_919783AC X-CRM114-Status: GOOD ( 12.70 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-pwm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Claudiu Beznea , linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Add PWM normal and complementary modes. Signed-off-by: Claudiu Beznea Acked-by: Rob Herring --- Documentation/devicetree/bindings/pwm/pwm.txt | 9 +++++++-- Documentation/pwm.txt | 26 +++++++++++++++++++++++--- include/dt-bindings/pwm/pwm.h | 1 + 3 files changed, 31 insertions(+), 5 deletions(-) diff --git a/Documentation/devicetree/bindings/pwm/pwm.txt b/Documentation/devicetree/bindings/pwm/pwm.txt index 8556263b8502..7c8aaac43f92 100644 --- a/Documentation/devicetree/bindings/pwm/pwm.txt +++ b/Documentation/devicetree/bindings/pwm/pwm.txt @@ -46,11 +46,16 @@ period in nanoseconds. Optionally, the pwm-specifier can encode a number of flags (defined in ) in a third cell: - PWM_POLARITY_INVERTED: invert the PWM signal polarity +- PWM_MODE_COMPLEMENTARY: PWM complementary working mode (for PWM channels +with two outputs); if not specified, the default for PWM channel will be +used -Example with optional PWM specifier for inverse polarity +Example with optional PWM specifier for inverse polarity and complementary +mode: bl: backlight { - pwms = <&pwm 0 5000000 PWM_POLARITY_INVERTED>; + pwms = <&pwm 0 5000000 + (PWM_MODE_COMPLEMENTARY | PWM_POLARITY_INVERTED)>; pwm-names = "backlight"; }; diff --git a/Documentation/pwm.txt b/Documentation/pwm.txt index 8fbf0aa3ba2d..912c43da8b48 100644 --- a/Documentation/pwm.txt +++ b/Documentation/pwm.txt @@ -61,9 +61,9 @@ In addition to the PWM state, the PWM API also exposes PWM arguments, which are the reference PWM config one should use on this PWM. PWM arguments are usually platform-specific and allows the PWM user to only care about dutycycle relatively to the full period (like, duty = 50% of the -period). struct pwm_args contains 2 fields (period and polarity) and should -be used to set the initial PWM config (usually done in the probe function -of the PWM user). PWM arguments are retrieved with pwm_get_args(). +period). struct pwm_args contains 3 fields (period, polarity and mode) and +should be used to set the initial PWM config (usually done in the probe +function of the PWM user). PWM arguments are retrieved with pwm_get_args(). Using PWMs with the sysfs interface ----------------------------------- @@ -110,6 +110,26 @@ channel that was exported. The following properties will then be available: - 0 - disabled - 1 - enabled + mode + Get/set PWM channel working mode. + + Normal mode - for PWM channels with one output; this should be the + default working mode for every PWM channel; output waveforms looks + like this: + __ __ __ __ + PWM __| |__| |__| |__| |__ + <--T--> + + Complementary mode - for PWM channels with two outputs; output waveforms + looks line this: + __ __ __ __ + PWMH1 __| |__| |__| |__| |__ + __ __ __ __ __ + PWML1 |__| |__| |__| |__| + <--T--> + + Where T is the signal period. + Implementing a PWM driver ------------------------- diff --git a/include/dt-bindings/pwm/pwm.h b/include/dt-bindings/pwm/pwm.h index ab9a077e3c7d..b82279cc1787 100644 --- a/include/dt-bindings/pwm/pwm.h +++ b/include/dt-bindings/pwm/pwm.h @@ -11,5 +11,6 @@ #define _DT_BINDINGS_PWM_PWM_H #define PWM_POLARITY_INVERTED (1 << 0) +#define PWM_MODE_COMPLEMENTARY (1 << 1) #endif