From patchwork Sat Jun 20 22:42:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Jonathan_Neusch=C3=A4fer?= X-Patchwork-Id: 198754 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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 BB7CEC433E2 for ; Sat, 20 Jun 2020 22:43:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 94AF724727 for ; Sat, 20 Jun 2020 22:43:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gmx.net header.i=@gmx.net header.b="YxTuL3n+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728425AbgFTWnV (ORCPT ); Sat, 20 Jun 2020 18:43:21 -0400 Received: from mout.gmx.net ([212.227.15.15]:46107 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728401AbgFTWnU (ORCPT ); Sat, 20 Jun 2020 18:43:20 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1592692957; bh=SdBTcHanE6ZbSETuw4jjAPlmlGZ23qUH4Z8rV7FhLqQ=; h=X-UI-Sender-Class:From:To:Cc:Subject:Date:In-Reply-To:References; b=YxTuL3n+V481rorkdamPXRDikXiZ4sMt+CjKxF7N/98UoosFo6tpOzlGWFGEWX8LQ FrAgzp+7ELpv2f3k2RR5PgS5R1JGO7IZDTFM43JWT9mCYGGt8pEr2Gf4fw/nUtyMQ2 Q+DpRzkhb3wal/Nxdl4tv8ABsVmOslJKe86GEpyQ= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from longitude ([5.146.194.186]) by mail.gmx.com (mrgmx005 [212.227.17.190]) with ESMTPSA (Nemesis) id 1Mdeb5-1jDiUW2ILp-00Zk6L; Sun, 21 Jun 2020 00:42:37 +0200 From: =?utf-8?q?Jonathan_Neusch=C3=A4fer?= To: linux-kernel@vger.kernel.org Cc: Lee Jones , Rob Herring , =?utf-8?q?Jonathan_Neusch=C3=A4fer?= , Thierry Reding , =?utf-8?q?Uwe_Kleine-K?= =?utf-8?b?w7ZuaWc=?= , Alessandro Zummo , Alexandre Belloni , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , NXP Linux Team , Sam Ravnborg , Linus Walleij , Heiko Stuebner , Stephan Gerhold , Lubomir Rintel , Mark Brown , allen , Mauro Carvalho Chehab , "David S. Miller" , devicetree@vger.kernel.org, linux-pwm@vger.kernel.org, linux-rtc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Heiko Stuebner , Josua Mayer , Andreas Kemnade Subject: [RFC PATCH 06/10] pwm: ntxec: Add driver for PWM function in Netronix EC Date: Sun, 21 Jun 2020 00:42:17 +0200 Message-Id: <20200620224222.1312520-5-j.neuschaefer@gmx.net> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200620224222.1312520-1-j.neuschaefer@gmx.net> References: <20200620224222.1312520-1-j.neuschaefer@gmx.net> MIME-Version: 1.0 X-Provags-ID: V03:K1:eUueW2vxa2QRAe4bcVFkBFTG7+5ALMF64PP7ISg/TUL89veAYiC zNUGbINCeiB6/qRtz4KAMnR3JUw7xGXKew+ZBUrBM10Q0UeTbHaaKg3U1aQSCDiw7aJ75Za BBGTWP6sb28uRrD0BeaGVgXJeGRFse0w/cyOUT9B79R1CPGIMv/z+IPZ0GlEQrMP7b2QryO ZibNSqbrHPhHazAKutaLg== X-UI-Out-Filterresults: notjunk:1; V03:K0:PnzBkUcOKAY=:V/ttZBJ1+lucSMD75nMnsM NcaH7eRcrfkSiMMtNRhBRb6dlxCaJNWhZcOHwJE4pvBxci7QR13NHaI5rVXfJKKRKipsRueQr pu+xkoqWqQQWc8MlcQlssPJHG7Lwp6w8J6FSyG3ADFOfyz9Mn2ojGY4JWyJ6yAKVRAOy5rfUf 4lqBNnCswq7wBvemfMX6tz0+N1NkFLcrm6bFGEDe06ZIhD85zKWQo2pDWEairDkxk8YTQ3ngd uXeWAeHAP6nziJ3D3URuKszcZc1YipjlrcKNybiM/LMKL6iqg8JvHCGRQNZPeGtuF0Smq8zw/ 9fn0zfYMLuu7bFTzUgHXpDQwcH+0olIbLlXTLIdZIOJEYokEyRxZdXe9uBOXx+9FUriGIzI6v 7wIC73OJU43mjtR7t9iPn0I+dVW8vFbnMllgBkqUvHA0puZhbjkkueXoJUDOvkZNWacAvpKMK 6brbCfpeI7ev3ItssXpNBpZj0HgX2pC/bmYQAdxLuvjR/qt/7l1iC/uzGcgX8vFM3xFC8+ZnG coYL7eTXJ7Y8WAn5wKSab5t/KhscnJFOslx8clj3k3Q1wjZQib1Zt7nLs981UHZQQGq+9M5Ej bJSlZiKjmcJvhc4HMb0tRsAhvqcRl7ZAEw3KuIJLlrrZGhYcGwIZt7lRfOG7dwL0Bf3DlYOkz xNFunhlzcgHK0YudeDBnlZYRW2I6ta2niX90haz+Ey2NilqYpqASSfhOoDyruBIS8R5Nk2jFo pYyscau9KBBCnfFkJ7fU45z+F99AAzH8p19xLqSJfLKwCsJvlxng3889fpOL8TVKXo0x/da8k lxoUu18wG6+D14kTz+Z1nOM0t23I+vFXkDOXPuQD80LLBO840c/djV/zHu+wU6JcMqw+KFRn0 0u65/B84cQqih5Yx8a7xOtriEWAhHpfv3ZHeI9JMTHH8M1k/NP0DL+8Km0UzXzk6JeQVW7knk jF5oAgSsPW/zIMcGLkZ9AEOFE8yT9a5TIbt3DR0psuqpGDr5PZE02aIsPJsD/7vDGTrvak8Vf tZUl7nvsY4ZTUEAFNuqt3IYNu5iW72E7hUUc0uNnWlL5roX0EbiAvzwUd4xq8xY2dXGLylqf1 ihgWpydBZJmc7tNGYNVVnq7qR/TXMrVcC/N33Cm5PT/0FSFUyAcP+iNDzoK/AHvRF8vo5KIM0 Z3i9Evmup2f6fATU3TCUE57JimLZ8AQ+egNfAs8lJZyQdojNsC4jM97SsQ1pjQyDwg4uxzE6K P28bc+lylSvUrFUxi Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org The Netronix EC provides a PWM output, which is used for the backlight on ebook readers. This patches adds a driver for the PWM output. Signed-off-by: Jonathan Neuschäfer --- drivers/pwm/Kconfig | 4 ++ drivers/pwm/Makefile | 1 + drivers/pwm/pwm-ntxec.c | 148 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 153 insertions(+) create mode 100644 drivers/pwm/pwm-ntxec.c -- 2.27.0 diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index cb8d739067d2f..147d6629e662c 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -350,6 +350,10 @@ config PWM_MXS To compile this driver as a module, choose M here: the module will be called pwm-mxs. +config PWM_NTXEC + tristate "Netronix embedded controller PWM support" + depends on MFD_NTXEC && OF + config PWM_OMAP_DMTIMER tristate "OMAP Dual-Mode Timer PWM support" depends on OF diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index a59c710e98c76..15507a6d9ca12 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -32,6 +32,7 @@ obj-$(CONFIG_PWM_MESON) += pwm-meson.o obj-$(CONFIG_PWM_MEDIATEK) += pwm-mediatek.o obj-$(CONFIG_PWM_MTK_DISP) += pwm-mtk-disp.o obj-$(CONFIG_PWM_MXS) += pwm-mxs.o +obj-$(CONFIG_PWM_NTXEC) += pwm-ntxec.o obj-$(CONFIG_PWM_OMAP_DMTIMER) += pwm-omap-dmtimer.o obj-$(CONFIG_PWM_PCA9685) += pwm-pca9685.o obj-$(CONFIG_PWM_PUV3) += pwm-puv3.o diff --git a/drivers/pwm/pwm-ntxec.c b/drivers/pwm/pwm-ntxec.c new file mode 100644 index 0000000000000..eca305d8e915b --- /dev/null +++ b/drivers/pwm/pwm-ntxec.c @@ -0,0 +1,148 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright 2020 Jonathan Neuschäfer +// +// PWM driver for Netronix embedded controller. + +#include +#include +#include +#include +#include +#include + +struct ntxec_pwm { + struct device *dev; + struct ntxec *ec; + struct pwm_chip chip; +}; + +static struct ntxec_pwm *pwmchip_to_pwm(struct pwm_chip *chip) +{ + return container_of(chip, struct ntxec_pwm, chip); +} + +#define NTXEC_UNK_A 0xa1 +#define NTXEC_UNK_B 0xa2 +#define NTXEC_ENABLE 0xa3 +#define NTXEC_PERIOD_LOW 0xa4 +#define NTXEC_PERIOD_HIGH 0xa5 +#define NTXEC_DUTY_LOW 0xa6 +#define NTXEC_DUTY_HIGH 0xa7 + +/* + * The time base used in the EC is 8MHz, or 125ns. Period and duty cycle are + * measured in this unit. + */ +static int ntxec_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm_dev, + int duty_ns, int period_ns) +{ + struct ntxec_pwm *pwm = pwmchip_to_pwm(chip); + uint64_t duty = duty_ns; + uint64_t period = period_ns; + int res = 0; + + do_div(period, 125); + if (period > 0xffff) { + dev_warn(pwm->dev, + "Period is not representable in 16 bits: %llu\n", period); + return -ERANGE; + } + + do_div(duty, 125); + if (duty > 0xffff) { + dev_warn(pwm->dev, "Duty cycle is not representable in 16 bits: %llu\n", + duty); + return -ERANGE; + } + + res |= ntxec_write8(pwm->ec, NTXEC_PERIOD_HIGH, period >> 8); + res |= ntxec_write8(pwm->ec, NTXEC_PERIOD_LOW, period); + res |= ntxec_write8(pwm->ec, NTXEC_DUTY_HIGH, duty >> 8); + res |= ntxec_write8(pwm->ec, NTXEC_DUTY_LOW, duty); + + return (res < 0) ? -EIO : 0; +} + +static int ntxec_pwm_enable(struct pwm_chip *chip, + struct pwm_device *pwm_dev) +{ + struct ntxec_pwm *pwm = pwmchip_to_pwm(chip); + + return ntxec_write8(pwm->ec, NTXEC_ENABLE, 1); +} + +static void ntxec_pwm_disable(struct pwm_chip *chip, + struct pwm_device *pwm_dev) +{ + struct ntxec_pwm *pwm = pwmchip_to_pwm(chip); + + ntxec_write8(pwm->ec, NTXEC_ENABLE, 0); +} + +static struct pwm_ops ntxec_pwm_ops = { + .config = ntxec_pwm_config, + .enable = ntxec_pwm_enable, + .disable = ntxec_pwm_disable, + .owner = THIS_MODULE, +}; + +static int ntxec_pwm_probe(struct platform_device *pdev) +{ + struct ntxec *ec = dev_get_drvdata(pdev->dev.parent); + struct ntxec_pwm *pwm; + struct pwm_chip *chip; + int res; + + pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL); + if (!pwm) + return -ENOMEM; + + pwm->ec = ec; + pwm->dev = &pdev->dev; + + chip = &pwm->chip; + chip->dev = &pdev->dev; + chip->ops = &ntxec_pwm_ops; + chip->base = -1; + chip->npwm = 1; + + res = pwmchip_add(chip); + if (res < 0) + return res; + + platform_set_drvdata(pdev, pwm); + + res |= ntxec_write8(pwm->ec, NTXEC_ENABLE, 0); + res |= ntxec_write8(pwm->ec, NTXEC_UNK_A, 0xff); + res |= ntxec_write8(pwm->ec, NTXEC_UNK_B, 0xff); + + return (res < 0) ? -EIO : 0; +} + +static int ntxec_pwm_remove(struct platform_device *pdev) +{ + struct ntxec_pwm *pwm = platform_get_drvdata(pdev); + struct pwm_chip *chip = &pwm->chip; + + return pwmchip_remove(chip); +} + +static const struct of_device_id ntxec_pwm_of_match[] = { + { .compatible = "netronix,ntxec-pwm" }, + { }, +}; +MODULE_DEVICE_TABLE(of, ntxec_pwm_of_match); + +static struct platform_driver ntxec_pwm_driver = { + .driver = { + .name = "ntxec-pwm", + .of_match_table = ntxec_pwm_of_match, + }, + .probe = ntxec_pwm_probe, + .remove = ntxec_pwm_remove, +}; +module_platform_driver(ntxec_pwm_driver); + +MODULE_AUTHOR("Jonathan Neuschäfer "); +MODULE_DESCRIPTION("PWM driver for Netronix EC"); +MODULE_LICENSE("GPL");