From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f176.google.com (mail-pl1-f176.google.com [209.85.214.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0660F156C76 for ; Fri, 14 Feb 2025 04:04:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.176 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739505855; cv=none; b=ow8xf6NSrm0bfdbYwwMvKqB+xD8fe6a3PwJjl5zazKKix9/gKyS1HYokdVZMnk6hDyAg8YOoUORpzvJH45VA/GlHJqMqBqh4cYX1mWrko9pbA1FhZy16bWjlGa3WdpCtJStJ/1IH4sJIz4gOJohEXfpckE2SdB03xXT08g8VIHk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739505855; c=relaxed/simple; bh=3GL2/WeIQojBOOSCQVtLEOFC8W4Kf1COEU0/3t8SOG0=; h=From:To:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XGAbrVzs729JDzrx98TIvsVywCoXq8G2wq9qlm1vEzLK1u1stTeLIBsfRU30p+xgap9w5CXo3hSh0EVJ/jpUqHycF7ieyhC7NgyQfj8lX82FnQ0KrN+GM3dId7thUlzKp03wZDiF+hDv2IunufWBwSUZeVqr7PH/K3C1xCvwWiY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=I6Xr5ArG; arc=none smtp.client-ip=209.85.214.176 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="I6Xr5ArG" Received: by mail-pl1-f176.google.com with SMTP id d9443c01a7336-220bfdfb3f4so33423685ad.2 for ; Thu, 13 Feb 2025 20:04:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1739505853; x=1740110653; darn=lists.linux.dev; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:from:to:cc:subject:date:message-id :reply-to; bh=THGbXf//SrScK+32A3BUuAqCods80KxGwHDBckzXHsI=; b=I6Xr5ArGMG0flpzM5NKg+fx+HL3Ko4D7dblY/Zbtq+O1a9T3P0z6HNVss3D+iFqN2n TKMTIxEzjbtJoYjj1XVzoHTzgRcg5TLmez8kSSfn09L7jT/m/sB5CeesYYQZgfVY9Nlq f4yFmiEivf0ojaRrZO4QaCTiSVKwCkhdgpCtfsyR64qg/cQhAL0ZOtpYZYPzWpaj1r8M YBNTZVW0Dl5lxB7lSbaHZy/eCGN+98B1mj5rdkn+2D78yqF/PpBTl5P2cKyEall9Faac eZNQT7yYwL4bkAS4vVRU0opaC5PHsATcqK+sIGfJXyEp/+etiuud39SIgGvBXUF9lnfm osWQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1739505853; x=1740110653; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=THGbXf//SrScK+32A3BUuAqCods80KxGwHDBckzXHsI=; b=pYz7vScjt1SBmBnyazySEx5c6L7EPAwTxV+3vYj+WX3G0f6YyhaToZGbN2+Mw8BcDI AEcnhL5MxCM53RHC6Ns5OdoMdXNw2DQvNeqZAyooKyUC0tQOWpypvq6zOPG/jCZV/Zo3 arcrSYGS3Ub3QpvotSH1yw9VQJjtJAYH1cUjpp/qCAeOxWsHFADxLVuiqeKZFduQuogl 0PX7pJ3o4WseCH1gJlHXCdqk87DoHI6p9dg29pFgafwwJzjOmaw+TYETU9IMbfEUD/sq oXHaU4R9iQ55bZAgN4Rmb0EXtnEpqmjyJTJ8qsKZF+H4U2KuiXjPUZhxXAb0NtKeMvxT Z3rg== X-Forwarded-Encrypted: i=1; AJvYcCX4L38utndpqoV2fNbuDIXu1+UP7Kd+Yc+qwzjb+syaY5/kdIpxzWmi6wEkXoIs1D4bptVXfA==@lists.linux.dev X-Gm-Message-State: AOJu0YyVA9vnHK5O0jcpZg18yKVnFgjDWdKv/Tq1cmGh8y3N/V2k0kEH adZJZU+XZ+HqID2v3gelS2OuXwMH+40H54IflvlAxBcwXLzTuZel X-Gm-Gg: ASbGncu6m8UCrZcotmLfK/pSJVx3dYXVWIsDsseyJhHC3Q0uik2U6pifXjThWEyaO+B d+/Q0cpIifv0GutC81uBx+ptGnupPqFHGynY73wDrELxBpfBeDVs0AKlP07GPd+B1Xv3E8YZJZC p0uHo4A/s25796H12+IG2ANv8/31nl2x0zLE6x9lPvCP9lDPmIeYcnw4aXT5uoQS+rDPqY28zEm mVjN3uuzUeri841LOnyMwPgD/6C/b+jhoX3+ugi2IkAts7z07V/14YbYNn5MtFZ5DNJMTWp2QvV finM8+e3FT11Luo= X-Google-Smtp-Source: AGHT+IGxivn76yELBYxib0w0BFCjx4VgWlcePDuyKrKPnZS1ISzc7Gxg04wRI/FeWDE8mSYuN0bpnA== X-Received: by 2002:a05:6a20:2585:b0:1ed:a812:8860 with SMTP id adf61e73a8af0-1ee5c796e7fmr16856578637.25.1739505853270; Thu, 13 Feb 2025 20:04:13 -0800 (PST) Received: from nick-mbp.. ([49.130.17.220]) by smtp.googlemail.com with ESMTPSA id d2e1a72fcca58-7324273e3e7sm2181227b3a.91.2025.02.13.20.04.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 13 Feb 2025 20:04:12 -0800 (PST) From: Nick Chan To: Janne Grunau , Sven Peter , Alyssa Rosenzweig , Lee Jones , Daniel Thompson , Jingoo Han , Pavel Machek , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Helge Deller , Nick Chan , asahi@lists.linux.dev, linux-arm-kernel@lists.infradead.org, dri-devel@lists.freedesktop.org, linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fbdev@vger.kernel.org Subject: [PATCH v6 2/3] backlight: apple_dwi_bl: Add Apple DWI backlight driver Date: Fri, 14 Feb 2025 12:02:13 +0800 Message-ID: <20250214040306.16312-3-towinchenmi@gmail.com> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250214040306.16312-1-towinchenmi@gmail.com> References: <20250214040306.16312-1-towinchenmi@gmail.com> Precedence: bulk X-Mailing-List: asahi@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Add driver for backlight controllers attached via Apple DWI 2-wire interface, which is found on some Apple iPhones, iPads and iPod touches with a LCD display. Although there is an existing apple_bl driver, it is for backlight controllers on Intel Macs attached via PCI, which is completely different from the Samsung-derived DWI block. Reviewed-by: Daniel Thompson (RISCstar) Signed-off-by: Nick Chan --- drivers/video/backlight/Kconfig | 11 +++ drivers/video/backlight/Makefile | 1 + drivers/video/backlight/apple_dwi_bl.c | 123 +++++++++++++++++++++++++ 3 files changed, 135 insertions(+) create mode 100644 drivers/video/backlight/apple_dwi_bl.c diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index 3614a5d29c71..cee113bba30f 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig @@ -290,6 +290,17 @@ config BACKLIGHT_APPLE If you have an Intel-based Apple say Y to enable a driver for its backlight. +config BACKLIGHT_APPLE_DWI + tristate "Apple DWI 2-Wire Interface Backlight Driver" + depends on ARCH_APPLE || COMPILE_TEST + help + Say Y to enable the backlight driver for backlight controllers + attached via the Apple DWI 2-wire interface which is found in some + Apple iPhones, iPads and iPod touches. + + To compile this driver as a module, choose M here: the module will + be called apple_dwi_bl. + config BACKLIGHT_QCOM_WLED tristate "Qualcomm PMIC WLED Driver" select REGMAP diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile index 8fc98f760a8a..156ff9461fb3 100644 --- a/drivers/video/backlight/Makefile +++ b/drivers/video/backlight/Makefile @@ -23,6 +23,7 @@ obj-$(CONFIG_BACKLIGHT_ADP5520) += adp5520_bl.o obj-$(CONFIG_BACKLIGHT_ADP8860) += adp8860_bl.o obj-$(CONFIG_BACKLIGHT_ADP8870) += adp8870_bl.o obj-$(CONFIG_BACKLIGHT_APPLE) += apple_bl.o +obj-$(CONFIG_BACKLIGHT_APPLE_DWI) += apple_dwi_bl.o obj-$(CONFIG_BACKLIGHT_AS3711) += as3711_bl.o obj-$(CONFIG_BACKLIGHT_BD6107) += bd6107.o obj-$(CONFIG_BACKLIGHT_CLASS_DEVICE) += backlight.o diff --git a/drivers/video/backlight/apple_dwi_bl.c b/drivers/video/backlight/apple_dwi_bl.c new file mode 100644 index 000000000000..93bd744972d6 --- /dev/null +++ b/drivers/video/backlight/apple_dwi_bl.c @@ -0,0 +1,123 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT +/* + * Driver for backlight controllers attached via Apple DWI 2-wire interface + * + * Copyright (c) 2024 Nick Chan + */ + +#include +#include +#include +#include +#include +#include + +#define DWI_BL_CTL 0x0 +#define DWI_BL_CTL_SEND1 BIT(0) +#define DWI_BL_CTL_SEND2 BIT(4) +#define DWI_BL_CTL_SEND3 BIT(5) +#define DWI_BL_CTL_LE_DATA BIT(6) +/* Only used on Apple A9 and later */ +#define DWI_BL_CTL_SEND4 BIT(12) + +#define DWI_BL_CMD 0x4 +#define DWI_BL_CMD_TYPE GENMASK(31, 28) +#define DWI_BL_CMD_TYPE_SET_BRIGHTNESS 0xa +#define DWI_BL_CMD_DATA GENMASK(10, 0) + +#define DWI_BL_CTL_SEND (DWI_BL_CTL_SEND1 | \ + DWI_BL_CTL_SEND2 | \ + DWI_BL_CTL_SEND3 | \ + DWI_BL_CTL_LE_DATA | \ + DWI_BL_CTL_SEND4) + +#define DWI_BL_MAX_BRIGHTNESS 2047 + +struct apple_dwi_bl { + void __iomem *base; +}; + +static int dwi_bl_update_status(struct backlight_device *bl) +{ + struct apple_dwi_bl *dwi_bl = bl_get_data(bl); + + int brightness = backlight_get_brightness(bl); + + u32 cmd = 0; + + cmd |= FIELD_PREP(DWI_BL_CMD_DATA, brightness); + cmd |= FIELD_PREP(DWI_BL_CMD_TYPE, DWI_BL_CMD_TYPE_SET_BRIGHTNESS); + + writel(cmd, dwi_bl->base + DWI_BL_CMD); + writel(DWI_BL_CTL_SEND, dwi_bl->base + DWI_BL_CTL); + + return 0; +} + +static int dwi_bl_get_brightness(struct backlight_device *bl) +{ + struct apple_dwi_bl *dwi_bl = bl_get_data(bl); + + u32 cmd = readl(dwi_bl->base + DWI_BL_CMD); + + return FIELD_GET(DWI_BL_CMD_DATA, cmd); +} + +static const struct backlight_ops dwi_bl_ops = { + .options = BL_CORE_SUSPENDRESUME, + .get_brightness = dwi_bl_get_brightness, + .update_status = dwi_bl_update_status +}; + +static int dwi_bl_probe(struct platform_device *dev) +{ + struct apple_dwi_bl *dwi_bl; + struct backlight_device *bl; + struct backlight_properties props; + struct resource *res; + + dwi_bl = devm_kzalloc(&dev->dev, sizeof(*dwi_bl), GFP_KERNEL); + if (!dwi_bl) + return -ENOMEM; + + dwi_bl->base = devm_platform_get_and_ioremap_resource(dev, 0, &res); + if (IS_ERR(dwi_bl->base)) + return PTR_ERR(dwi_bl->base); + + memset(&props, 0, sizeof(struct backlight_properties)); + props.type = BACKLIGHT_PLATFORM; + props.max_brightness = DWI_BL_MAX_BRIGHTNESS; + props.scale = BACKLIGHT_SCALE_LINEAR; + + bl = devm_backlight_device_register(&dev->dev, dev->name, &dev->dev, + dwi_bl, &dwi_bl_ops, &props); + if (IS_ERR(bl)) + return PTR_ERR(bl); + + platform_set_drvdata(dev, dwi_bl); + + bl->props.brightness = dwi_bl_get_brightness(bl); + + return 0; +} + +static const struct of_device_id dwi_bl_of_match[] = { + { .compatible = "apple,dwi-bl" }, + {}, +}; + +MODULE_DEVICE_TABLE(of, dwi_bl_of_match); + +static struct platform_driver dwi_bl_driver = { + .driver = { + .name = "apple-dwi-bl", + .of_match_table = dwi_bl_of_match + }, + .probe = dwi_bl_probe, +}; + +module_platform_driver(dwi_bl_driver); + +MODULE_DESCRIPTION("Apple DWI Backlight Driver"); +MODULE_AUTHOR("Nick Chan "); +MODULE_LICENSE("Dual MIT/GPL"); -- 2.48.1