From patchwork Mon May 17 14:36:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: ChiYuan Huang X-Patchwork-Id: 12262339 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 A8C05C41602 for ; Mon, 17 May 2021 15:46:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 88659611CA for ; Mon, 17 May 2021 15:46:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244998AbhEQPrX (ORCPT ); Mon, 17 May 2021 11:47:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57360 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344265AbhEQPoJ (ORCPT ); Mon, 17 May 2021 11:44:09 -0400 Received: from mail-pf1-x433.google.com (mail-pf1-x433.google.com [IPv6:2607:f8b0:4864:20::433]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 55872C043150; Mon, 17 May 2021 07:36:26 -0700 (PDT) Received: by mail-pf1-x433.google.com with SMTP id 10so5096499pfl.1; Mon, 17 May 2021 07:36:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=4VfONO8iWnXjc4bLmF+kdWkzrEctN65wmhdy3hiN/bI=; b=Gw2Xwc1x3cyvkoRyl6YobgRb7PM/E7K4yVvXc5I0XuM1izbFjPhHAS0yd+yBegah4u YUy2UozzrTNzFygBeimnimV/yCgV2S3ALQMsGk6vOD8XfRxUXedZ4tYbRV/FP6JOxjlF Ykk3huWixd+8MaBG2qiSkoQLfs2n1k+D1iB8SV6EQu+BsyN1Am7FvDT6Cow2x71JjyMy eMvQX1tnGNH9awPvFvSgHLbuT55Iw1DRtQXw95N0OTAdFZjSXQdjk2FJoaYES9Z+V+9j yd4sETLJjI1j8CVTnSFgPLmmQnS4d1N5bI5Yrsa2O+iJFoeXnT8uV5/o70FAaaX6t3rE CTJw== 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:in-reply-to :references; bh=4VfONO8iWnXjc4bLmF+kdWkzrEctN65wmhdy3hiN/bI=; b=e2usDkMN4WDsMTsYvkcdf1nZsQ0xKzYRgOjOA8l7HyQOmUDpzhxBsXk1/Ot+bLucth +ggI7MTl4X//qIQiyyPpRke30A4K/OgI9zQ9WsBhukK00keLlU4HGJGfz19Xu7qyMJqe 3xMDa6xEP9sMWSWCJTb32u7swKVfwmX6fnxsXMXlzweJJSANtOx2A9Wxe3PtYHeTBgnG laOy0Llqb0hdnm0OKOuOP5P3z/LkHvp+SbyAWeBW0FmFspw87pxVpwG0d+JjxAwO7IYE Pjz9ETZGRMpe4RFUyvBHGM5VzYJwMcAuZ4JB8I2QWTQVHPGDv00UxX/LuX46/zsVo4dw 8hIA== X-Gm-Message-State: AOAM5318s8bLhI3BRdtn9j1tcbG87KtcwGSJbATtzOW+Be0MR7sgBcoC jqALQZqxuml2Yh8X9cdWCaQ= X-Google-Smtp-Source: ABdhPJxzf6k2ylSvroGza4Ure+vEOAciMAww2/kckmArSUX1c2cAkp/nEQeV926Bm3H6+CEtwU1bfw== X-Received: by 2002:a62:2fc6:0:b029:28e:854b:20b3 with SMTP id v189-20020a622fc60000b029028e854b20b3mr42709pfv.0.1621262185820; Mon, 17 May 2021 07:36:25 -0700 (PDT) Received: from localhost.localdomain (1-171-3-209.dynamic-ip.hinet.net. [1.171.3.209]) by smtp.gmail.com with ESMTPSA id f5sm13880259pjp.37.2021.05.17.07.36.22 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 17 May 2021 07:36:25 -0700 (PDT) From: cy_huang To: lee.jones@linaro.org, lgirdwood@gmail.com, broonie@kernel.org, daniel.thompson@linaro.org, jingoohan1@gmail.com, b.zolnierkie@samsung.com, pavel@ucw.cz, robh+dt@kernel.org Cc: dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-leds@vger.kernel.org, devicetree@vger.kernel.org, cy_huang@richtek.com Subject: [PATCH v7 4/4] backlight: rt4831: Adds support for Richtek RT4831 backlight Date: Mon, 17 May 2021 22:36:01 +0800 Message-Id: <1621262161-9972-4-git-send-email-u0084500@gmail.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1621262161-9972-1-git-send-email-u0084500@gmail.com> References: <1621262161-9972-1-git-send-email-u0084500@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org From: ChiYuan Huang Adds support for Richtek RT4831 backlight. Signed-off-by: ChiYuan Huang Reviewed-by: Daniel Thompson --- since v7 - Fix typo 'common' to 'commonly' in Kconfig description. --- drivers/video/backlight/Kconfig | 8 ++ drivers/video/backlight/Makefile | 1 + drivers/video/backlight/rt4831-backlight.c | 203 +++++++++++++++++++++++++++++ 3 files changed, 212 insertions(+) create mode 100644 drivers/video/backlight/rt4831-backlight.c diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index d83c87b..858f6df 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig @@ -289,6 +289,14 @@ config BACKLIGHT_QCOM_WLED If you have the Qualcomm PMIC, say Y to enable a driver for the WLED block. Currently it supports PM8941 and PMI8998. +config BACKLIGHT_RT4831 + tristate "Richtek RT4831 Backlight Driver" + depends on MFD_RT4831 + help + This enables support for Richtek RT4831 Backlight driver. + It's commonly used to drive the display WLED. There're four channels + inisde, and each channel can provide up to 30mA current. + config BACKLIGHT_SAHARA tristate "Tabletkiosk Sahara Touch-iT Backlight Driver" depends on X86 diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile index 685f3f1..cae2c83 100644 --- a/drivers/video/backlight/Makefile +++ b/drivers/video/backlight/Makefile @@ -49,6 +49,7 @@ obj-$(CONFIG_BACKLIGHT_PANDORA) += pandora_bl.o obj-$(CONFIG_BACKLIGHT_PCF50633) += pcf50633-backlight.o obj-$(CONFIG_BACKLIGHT_PWM) += pwm_bl.o obj-$(CONFIG_BACKLIGHT_QCOM_WLED) += qcom-wled.o +obj-$(CONFIG_BACKLIGHT_RT4831) += rt4831-backlight.o obj-$(CONFIG_BACKLIGHT_SAHARA) += kb3886_bl.o obj-$(CONFIG_BACKLIGHT_SKY81452) += sky81452-backlight.o obj-$(CONFIG_BACKLIGHT_TOSA) += tosa_bl.o diff --git a/drivers/video/backlight/rt4831-backlight.c b/drivers/video/backlight/rt4831-backlight.c new file mode 100644 index 00000000..42155c7 --- /dev/null +++ b/drivers/video/backlight/rt4831-backlight.c @@ -0,0 +1,203 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include +#include +#include +#include +#include +#include +#include +#include + +#define RT4831_REG_BLCFG 0x02 +#define RT4831_REG_BLDIML 0x04 +#define RT4831_REG_ENABLE 0x08 + +#define RT4831_BLMAX_BRIGHTNESS 2048 + +#define RT4831_BLOVP_MASK GENMASK(7, 5) +#define RT4831_BLOVP_SHIFT 5 +#define RT4831_BLPWMEN_MASK BIT(0) +#define RT4831_BLEN_MASK BIT(4) +#define RT4831_BLCH_MASK GENMASK(3, 0) +#define RT4831_BLDIML_MASK GENMASK(2, 0) +#define RT4831_BLDIMH_MASK GENMASK(10, 3) +#define RT4831_BLDIMH_SHIFT 3 + +struct rt4831_priv { + struct device *dev; + struct regmap *regmap; + struct backlight_device *bl; +}; + +static int rt4831_bl_update_status(struct backlight_device *bl_dev) +{ + struct rt4831_priv *priv = bl_get_data(bl_dev); + int brightness = backlight_get_brightness(bl_dev); + unsigned int enable = brightness ? RT4831_BLEN_MASK : 0; + u8 v[2]; + int ret; + + if (brightness) { + v[0] = (brightness - 1) & RT4831_BLDIML_MASK; + v[1] = ((brightness - 1) & RT4831_BLDIMH_MASK) >> RT4831_BLDIMH_SHIFT; + + ret = regmap_raw_write(priv->regmap, RT4831_REG_BLDIML, v, sizeof(v)); + if (ret) + return ret; + } + + return regmap_update_bits(priv->regmap, RT4831_REG_ENABLE, RT4831_BLEN_MASK, enable); + +} + +static int rt4831_bl_get_brightness(struct backlight_device *bl_dev) +{ + struct rt4831_priv *priv = bl_get_data(bl_dev); + unsigned int val; + u8 v[2]; + int ret; + + ret = regmap_read(priv->regmap, RT4831_REG_ENABLE, &val); + if (ret) + return ret; + + if (!(val & RT4831_BLEN_MASK)) + return 0; + + ret = regmap_raw_read(priv->regmap, RT4831_REG_BLDIML, v, sizeof(v)); + if (ret) + return ret; + + ret = (v[1] << RT4831_BLDIMH_SHIFT) + (v[0] & RT4831_BLDIML_MASK) + 1; + + return ret; +} + +static const struct backlight_ops rt4831_bl_ops = { + .options = BL_CORE_SUSPENDRESUME, + .update_status = rt4831_bl_update_status, + .get_brightness = rt4831_bl_get_brightness, +}; + +static int rt4831_parse_backlight_properties(struct rt4831_priv *priv, + struct backlight_properties *bl_props) +{ + struct device *dev = priv->dev; + u8 propval; + u32 brightness; + unsigned int val = 0; + int ret; + + /* common properties */ + ret = device_property_read_u32(dev, "max-brightness", &brightness); + if (ret) + brightness = RT4831_BLMAX_BRIGHTNESS; + + bl_props->max_brightness = min_t(u32, brightness, RT4831_BLMAX_BRIGHTNESS); + + ret = device_property_read_u32(dev, "default-brightness", &brightness); + if (ret) + brightness = bl_props->max_brightness; + + bl_props->brightness = min_t(u32, brightness, bl_props->max_brightness); + + /* vendor properties */ + if (device_property_read_bool(dev, "richtek,pwm-enable")) + val = RT4831_BLPWMEN_MASK; + + ret = regmap_update_bits(priv->regmap, RT4831_REG_BLCFG, RT4831_BLPWMEN_MASK, val); + if (ret) + return ret; + + ret = device_property_read_u8(dev, "richtek,bled-ovp-sel", &propval); + if (ret) + propval = RT4831_BLOVPLVL_21V; + + propval = min_t(u8, propval, RT4831_BLOVPLVL_29V); + ret = regmap_update_bits(priv->regmap, RT4831_REG_BLCFG, RT4831_BLOVP_MASK, + propval << RT4831_BLOVP_SHIFT); + if (ret) + return ret; + + ret = device_property_read_u8(dev, "richtek,channel-use", &propval); + if (ret) { + dev_err(dev, "richtek,channel-use DT property missing\n"); + return ret; + } + + if (!(propval & RT4831_BLCH_MASK)) { + dev_err(dev, "No channel specified\n"); + return -EINVAL; + } + + return regmap_update_bits(priv->regmap, RT4831_REG_ENABLE, RT4831_BLCH_MASK, propval); +} + +static int rt4831_bl_probe(struct platform_device *pdev) +{ + struct rt4831_priv *priv; + struct backlight_properties bl_props = { .type = BACKLIGHT_RAW, + .scale = BACKLIGHT_SCALE_LINEAR }; + int ret; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->dev = &pdev->dev; + + priv->regmap = dev_get_regmap(pdev->dev.parent, NULL); + if (!priv->regmap) { + dev_err(&pdev->dev, "Failed to init regmap\n"); + return -ENODEV; + } + + ret = rt4831_parse_backlight_properties(priv, &bl_props); + if (ret) { + dev_err(&pdev->dev, "Failed to parse backlight properties\n"); + return ret; + } + + priv->bl = devm_backlight_device_register(&pdev->dev, pdev->name, &pdev->dev, priv, + &rt4831_bl_ops, &bl_props); + if (IS_ERR(priv->bl)) { + dev_err(&pdev->dev, "Failed to register backlight\n"); + return PTR_ERR(priv->bl); + } + + backlight_update_status(priv->bl); + platform_set_drvdata(pdev, priv); + + return 0; +} + +static int rt4831_bl_remove(struct platform_device *pdev) +{ + struct rt4831_priv *priv = platform_get_drvdata(pdev); + struct backlight_device *bl_dev = priv->bl; + + bl_dev->props.brightness = 0; + backlight_update_status(priv->bl); + + return 0; +} + +static const struct of_device_id __maybe_unused rt4831_bl_of_match[] = { + { .compatible = "richtek,rt4831-backlight", }, + {} +}; +MODULE_DEVICE_TABLE(of, rt4831_bl_of_match); + +static struct platform_driver rt4831_bl_driver = { + .driver = { + .name = "rt4831-backlight", + .of_match_table = rt4831_bl_of_match, + }, + .probe = rt4831_bl_probe, + .remove = rt4831_bl_remove, +}; +module_platform_driver(rt4831_bl_driver); + +MODULE_AUTHOR("ChiYuan Huang "); +MODULE_LICENSE("GPL v2");