From patchwork Sat May 25 18:11:19 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Blumenstingl X-Patchwork-Id: 10961077 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 C6B4E14B6 for ; Sat, 25 May 2019 18:29:58 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B993828A86 for ; Sat, 25 May 2019 18:29:58 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AE03628A8E; Sat, 25 May 2019 18:29:58 +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=-5.2 required=2.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED,DKIM_VALID,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable 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 4A4ED28A86 for ; Sat, 25 May 2019 18:29:58 +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: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:In-Reply-To:References: List-Owner; bh=uiTP8g8le5SdKHtJmU+mb26/+8sHjuGusQAptbcnBrE=; b=qN4IB4lB+bwGzX 0wFKaiqs/xpsLZSLvZQk0yhgSnZj+46FyfyKG7T1idUfxRagbjvAPcULDe0zZmdeidHF9ud40zvKd yX3VUyDG9X6LN2ZYrNmb9KSBpz/qRoApkS9qtcsqlfR7WLfiVB7qxEpW3yS1Em1yv+Mg7bzXH8Y1l jV+Sey2lsA6+cGNItvbBL5YWd6G2arkGGdyPCDJYc6zPgJLu5yw+iqfeKBflLN5baJoX0lLB/rrIF XwmCyTktJkZddlBsdhXkhTNaktpielO6uaish8U8/wpKTemL7sxRn6d6TlHJt5z7o9z0cE6OLB/r8 deVS9u9DVA476QiPD3ag==; 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 1hUbQX-0004eh-2I; Sat, 25 May 2019 18:29:53 +0000 Received: from casper.infradead.org ([2001:8b0:10b:1236::1]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hUbQ8-0003yY-FW; Sat, 25 May 2019 18:29:28 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:Content-Type: MIME-Version:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=1Yb/S5cquO/qD7cZ8y/Ty2KEWw38/es4qeSEZUyR+jc=; b=DA2XRAo4/42BjE5N25wrSNegWJ 3m9X/DkXpaCv8XYfkDU6rb9zWF/lpYhavOckzBVx1Mvt/C4X8PqXGTH6rXLipwB5Z7Z2TsH9KeZyh vJqhm+7TMmhMCfBsMpEv9h9C3B9Ih6SDQLk0eGLlIXuEI/WRLUw92G/1dpP4fzgtJRv6tC8PEvNtz juDSL0cyydQ9Bg0neDwZaLFxI7N8yseCN/Z8S3qnoLd0W0Iy+jpnnddXpE4e96KX9ePFoP1qGZFcr 2pZABig6sZho955oufOCMq+36S8WMOckYIohXEk82s0+5+EyUk5DNup8HrfQY175pAZGaPk3YEDaU 909Y9GVA==; Received: from mail-wr1-x442.google.com ([2a00:1450:4864:20::442]) by casper.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hUb90-00024t-8A; Sat, 25 May 2019 18:11:48 +0000 Received: by mail-wr1-x442.google.com with SMTP id w13so4590523wru.11; Sat, 25 May 2019 11:11:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=1Yb/S5cquO/qD7cZ8y/Ty2KEWw38/es4qeSEZUyR+jc=; b=OGJNTZfDrBzPN439RB++aRKeudPMkKmAnuPSKbCnLRPL0eV+S2U2ujtLWuKIW3R1/V tR+Vi1PNTFdC3hGP5egqzB5KZrLyec9thl7qdXa7ZIVQeM50/fuANNeD/xx2+zjavcfh Sot/dtNJhrUJ3CN3JWpD0bZEgn1Xr1TDXlo4Y3rXszL9ELsilnxHcpQutZ5dmQ95q+da O+cChUMRweL+GBgKmh1Swu+H8mtFOj4Ri6QVjHAt5zCjyhpT6mXWZBSD+SU+1eh04PNv rZm1iK+/8a/D9sCSzxE+GWi1gyxowb2WaeDIN2BLFZgY4xFUTPexkmSwSdQnPV+9iF8d jSNg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=1Yb/S5cquO/qD7cZ8y/Ty2KEWw38/es4qeSEZUyR+jc=; b=T/jXCIdXQTypz8prJ5KQej6nuSh4IXjXYplweZuhd4fxMPU9Kg/Emsl7b8p+HM4XqL qRoRw7pZO1aDsMrxALUmWQUEO0n1P1onyA40wWVLUus5xk+8p4wYTvtXNcXW+wIXAtId tfPOSx0YYviraigLd7zlkSIe9RMDPvU7PEcVmR/1stRTbHG9lXUyDMLDWA9YutK+phx8 aEE2bkAx4HyHJrkkR5LadTpDRs8scwD23/4A21toQh8IdLhlc0U7oUXFtbanC6necQ/I cN/NnDVIvJroRt+zilOjAswBO/2Y/D8puQ1i5xugD/swhY69O2n3CorcQxGCoHH+Nrbs fhCg== X-Gm-Message-State: APjAAAXp7P6Y5BK2CjDs7Tj5gGPNzRUO++bp+u4Vum0cyhkAE1Hvmowa 5S33wNnbVnmF3gRfzJOqIZGS3isW X-Google-Smtp-Source: APXvYqxBZiRxV8q08TSMKchVl/GQr4AJB1E/7X1Qboxu7UaF1qNqvJ7pwpHbrpQvTRZKOmexP2cjYw== X-Received: by 2002:adf:f78d:: with SMTP id q13mr20308734wrp.220.1558807903867; Sat, 25 May 2019 11:11:43 -0700 (PDT) Received: from blackbox.darklights.net (p200300F133DDA4007CB8841254CD64FD.dip0.t-ipconnect.de. [2003:f1:33dd:a400:7cb8:8412:54cd:64fd]) by smtp.googlemail.com with ESMTPSA id o8sm12794540wra.4.2019.05.25.11.11.42 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 25 May 2019 11:11:42 -0700 (PDT) From: Martin Blumenstingl To: linux-amlogic@lists.infradead.org, linux-pwm@vger.kernel.org, thierry.reding@gmail.com, u.kleine-koenig@pengutronix.de Subject: [PATCH 00/14] pwm-meson: cleanups and improvements Date: Sat, 25 May 2019 20:11:19 +0200 Message-Id: <20190525181133.4875-1-martin.blumenstingl@googlemail.com> X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190525_191146_361004_0E39DDF6 X-CRM114-Status: GOOD ( 17.89 ) 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: Martin Blumenstingl , linux-kernel@vger.kernel.org, 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 This series consists of various cleanups and improvements for the pwm-meson driver. Patches 1 to 6 are small code cleanups with the goal of making the code easier to read. Patches 7 to 9 are reworking the way the per-channel settings are accessed. This is a first preparation step for adding full support to meson_pwm_get_state() in the pwm-meson driver. Patch 7 makes struct meson_pwm_channel accessible from struct meson_pwm because meson_pwm_get_state() cannot use pwm_get_chip_data(). Patch 8 removes redundant switch/case statements and ensures that we don't have to add another redundant one for the upcoming full meson_pwm_get_state() implementation. Patch 9 gets rid of meson_pwm_add_channels() and moves the pwm_set_chip_data() call to meson_pwm_request() (like all other PWM drivers do - except two). Patch 10 is based on a suggestion by Uwe to simplify the calculation of the values which the PWM IP requires. The nice benefit of this is that we have an easier calculation which we can do "in reverse" for the meson_pwm_get_state() (which calculates nanoseconds from the hardware values). Patch 11 implements reading the period and duty cycle in the meson_pwm_get_state() callback. Patch 12 removes some internal caching which we don't need anymore now meson_pwm_get_state() is fully implemented. The PWM core now takes care of not calling pwm_ops.apply() if "nothing has changed". Patch 13 adds support for PWM_POLARITY_INVERSED when disabling the output as suggested by Uwe. Patch 14 completes this series by adding some documentation to the driver. Thanks to Neil for summarizing how the hardware works internally. Due to the changed PWM calculation in patch 10 I have verified that we don't break any existing boards. The patch itself contains two examples which show that the new calculation improves precision. I made screenshots of the measurements in pulseview [0] for the second case ("PWM LED on Khadas VIM"): - old algorithm: [1] - old algorithm: [2] Dependencies: This series applies on top of Neil's patch "pwm: pwm-meson: update with SPDX Licence identifier" [3] [0] https://sigrok.org/wiki/PulseView [1] https://abload.de/img/old-algormjs9.png [2] https://abload.de/img/new-algo4ckjo.png [3] https://patchwork.kernel.org/patch/10951319/ Martin Blumenstingl (14): pwm: meson: unify the parameter list of meson_pwm_{enable,disable} pwm: meson: use devm_clk_get_optional() to get the input clock pwm: meson: use GENMASK and FIELD_PREP for the lo and hi values pwm: meson: change MISC_CLK_SEL_WIDTH to MISC_CLK_SEL_MASK pwm: meson: don't duplicate the polarity internally pwm: meson: pass struct pwm_device to meson_pwm_calc() pwm: meson: add the meson_pwm_channel data to struct meson_pwm pwm: meson: add the per-channel register offsets and bits in a struct pwm: meson: move pwm_set_chip_data() to meson_pwm_request() pwm: meson: simplify the calculation of the pre-divider and count pwm: meson: read the full hardware state in meson_pwm_get_state() pwm: meson: don't cache struct pwm_state internally pwm: meson: add support PWM_POLARITY_INVERSED when disabling pwm: meson: add documentation to the driver drivers/pwm/pwm-meson.c | 323 +++++++++++++++++++++------------------- 1 file changed, 169 insertions(+), 154 deletions(-)