From patchwork Mon Jul 8 10:26:57 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jean-Jacques Hiblot X-Patchwork-Id: 168606 Delivered-To: patch@linaro.org Received: by 2002:a92:4782:0:0:0:0:0 with SMTP id e2csp6962440ilk; Mon, 8 Jul 2019 03:27:19 -0700 (PDT) X-Google-Smtp-Source: APXvYqzfdP+31gsy9eTIcc5e1MBENhZDuiWTpvSiXThHFiwAZ7fqAzWyPgYrvvE90Ve5Wjt7D5Lf X-Received: by 2002:a17:902:7281:: with SMTP id d1mr23276787pll.329.1562581639396; Mon, 08 Jul 2019 03:27:19 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1562581639; cv=none; d=google.com; s=arc-20160816; b=ETSvNtA/tAiPL//mV2OjIvJv8BWHO7qNReIBfXw1n3hnyU2yL4OAwZvSCQJjGmaqYI uqV+/AY9TCc7W+DUm0z00BlLUMhRjwu8y/6o3xIzlYv7CY1NMBOYt6d9W5MC3xJPUjLR ZxXyfUkuZ3MtIP0I9rT2JIGYWRtaa0fK3o59zzJEY3EDt7AwbRC4ZPvUyxrt9JrUf3mS O27RwlENmSk0sxIIXm87/P59yVvwD3n9JpyRPtfqKh/aSTBMr0Twiw0x7KyRoRI0lVs8 GZ6wwBxHLqwp/ggznPJUj/zyF13p6cYKaRcd6BRMiVQJxibafTBjOxxhqotz5DHCEh2p xNsw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=sender:errors-to:content-transfer-encoding:cc:list-subscribe :list-help:list-post:list-archive:list-unsubscribe:list-id :precedence:mime-version:references:in-reply-to:message-id:date :subject:to:from:delivered-to; bh=RsE0efEVT7zKkrxRpOaiGngkfxgyQ9cG9TittY2aock=; b=N6+mNjv99YmSFKw+gk7XzljcEI3nw0VRokXefyPhVaKp1Hy+djZUhYX3QHzF9BCBZo zqq2fsSENiSVKzqJbYsOu8C+CvjX3I0IFMzXV1jjnZzcA/hzVu9YvnjHabtvx9DwfVSN p05fjsdszMo8AmcC10mstupSBoZoKGBBPsTx8Sy1DL+3oKy15crzVDCdL+wYWh7qmpcg 4evBieYmRif4SCAPGCf7xn2i1+dPS5LTr3yNxI4IsX+vmNTUvFKH8QbS92YtuhVv6ykO Da/nUPYfRxWBINnLcs9r1HmgogLySnDpOuRuBIQohlxK+X7tnyYi8VjJ5H/uC6WdEeY3 bt7A== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of dri-devel-bounces@lists.freedesktop.org designates 2610:10:20:722:a800:ff:fe36:1795 as permitted sender) smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org; dmarc=fail (p=QUARANTINE sp=NONE dis=QUARANTINE) header.from=ti.com Return-Path: Received: from gabe.freedesktop.org (gabe.freedesktop.org. [2610:10:20:722:a800:ff:fe36:1795]) by mx.google.com with ESMTPS id 3si17826131plp.31.2019.07.08.03.27.19 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 08 Jul 2019 03:27:19 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of dri-devel-bounces@lists.freedesktop.org designates 2610:10:20:722:a800:ff:fe36:1795 as permitted sender) client-ip=2610:10:20:722:a800:ff:fe36:1795; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of dri-devel-bounces@lists.freedesktop.org designates 2610:10:20:722:a800:ff:fe36:1795 as permitted sender) smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org; dmarc=fail (p=QUARANTINE sp=NONE dis=QUARANTINE) header.from=ti.com Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2E53089C60; Mon, 8 Jul 2019 10:27:15 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from lelv0142.ext.ti.com (lelv0142.ext.ti.com [198.47.23.249]) by gabe.freedesktop.org (Postfix) with ESMTPS id CA09989C54 for ; Mon, 8 Jul 2019 10:27:13 +0000 (UTC) Received: from lelv0266.itg.ti.com ([10.180.67.225]) by lelv0142.ext.ti.com (8.15.2/8.15.2) with ESMTP id x68AR8Ek001158; Mon, 8 Jul 2019 05:27:08 -0500 Received: from DFLE102.ent.ti.com (dfle102.ent.ti.com [10.64.6.23]) by lelv0266.itg.ti.com (8.15.2/8.15.2) with ESMTPS id x68AR88q111993 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 8 Jul 2019 05:27:08 -0500 Received: from DFLE110.ent.ti.com (10.64.6.31) by DFLE102.ent.ti.com (10.64.6.23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5; Mon, 8 Jul 2019 05:27:08 -0500 Received: from fllv0040.itg.ti.com (10.64.41.20) by DFLE110.ent.ti.com (10.64.6.31) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5 via Frontend Transport; Mon, 8 Jul 2019 05:27:08 -0500 Received: from localhost (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0040.itg.ti.com (8.15.2/8.15.2) with ESMTP id x68AR7tK074648; Mon, 8 Jul 2019 05:27:08 -0500 From: Jean-Jacques Hiblot To: , , , , , , Subject: [PATCH v2 1/4] leds: Add of_led_get() and led_put() Date: Mon, 8 Jul 2019 12:26:57 +0200 Message-ID: <20190708102700.23138-2-jjhiblot@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190708102700.23138-1-jjhiblot@ti.com> References: <20190708102700.23138-1-jjhiblot@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1562581628; bh=nU97vt4bCNmMA9ZfacNjLitUhnqsxdeLpbW/G535FUs=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=IALIVZ21mIgDrPQI8jb8XaoY+HoEAvL97SpvScqL1dZifhh55mpNjUuNv3uAePeZM Mr15vfe+1wW4KqcfwBDzBwtIXbotJRgrpwxIbvpqIOb8Zb/h9FAfDVcxEhB9veIUdK AOMfvHnuUOqgdUMexlPR8L8CTjNvHIjY1Jqfdj2A= X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, tomi.valkeinen@ti.com, dmurphy@ti.com, Jean-Jacques Hiblot , linux-leds@vger.kernel.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Tomi Valkeinen This patch adds basic support for a kernel driver to get a LED device. This will be used by the led-backlight driver. Only OF version is implemented for now, and the behavior is similar to PWM's of_pwm_get() and pwm_put(). Signed-off-by: Tomi Valkeinen Signed-off-by: Jean-Jacques Hiblot --- drivers/leds/led-class.c | 50 ++++++++++++++++++++++++++++++++++++++++ include/linux/leds.h | 4 ++++ 2 files changed, 54 insertions(+) diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c index e01b2d982564..0f67b13b0f1f 100644 --- a/drivers/leds/led-class.c +++ b/drivers/leds/led-class.c @@ -19,6 +19,7 @@ #include #include #include +#include #include "leds.h" static struct class *leds_class; @@ -214,6 +215,55 @@ static int led_resume(struct device *dev) static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume); +static int led_match_led_node(struct device *led_dev, const void *data) +{ + return led_dev->of_node == data ? 1 : 0; +} + +/** + * of_led_get() - request a LED device via the LED framework + * @np: device node to get the LED device from + * @index: the index of the LED + * + * Returns the LED device parsed from the phandle specified in the "leds" + * property of a device tree node or a negative error-code on failure. + */ +struct led_classdev *of_led_get(struct device_node *np, int index) +{ + struct device *led_dev; + struct led_classdev *led_cdev; + struct device_node *led_node; + + led_node = of_parse_phandle(np, "leds", index); + if (!led_node) + return ERR_PTR(-ENOENT); + + led_dev = class_find_device(leds_class, NULL, led_node, + led_match_led_node); + of_node_put(led_node); + + if (!led_dev) + return ERR_PTR(-EPROBE_DEFER); + + led_cdev = dev_get_drvdata(led_dev); + + if (!try_module_get(led_cdev->dev->parent->driver->owner)) + return ERR_PTR(-ENODEV); + + return led_cdev; +} +EXPORT_SYMBOL_GPL(of_led_get); + +/** + * led_put() - release a LED device + * @led_cdev: LED device + */ +void led_put(struct led_classdev *led_cdev) +{ + module_put(led_cdev->dev->parent->driver->owner); +} +EXPORT_SYMBOL_GPL(led_put); + static int match_name(struct device *dev, const void *data) { if (!dev_name(dev)) diff --git a/include/linux/leds.h b/include/linux/leds.h index bee8e3f8dddd..0a71c7cdd191 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -19,6 +19,7 @@ struct device; struct led_pattern; +struct device_node; /* * LED Core */ @@ -145,6 +146,9 @@ extern void devm_led_classdev_unregister(struct device *parent, extern void led_classdev_suspend(struct led_classdev *led_cdev); extern void led_classdev_resume(struct led_classdev *led_cdev); +extern struct led_classdev *of_led_get(struct device_node *np, int index); +extern void led_put(struct led_classdev *led_cdev); + /** * led_blink_set - set blinking with software fallback * @led_cdev: the LED to start blinking From patchwork Mon Jul 8 10:27:00 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jean-Jacques Hiblot X-Patchwork-Id: 168607 Delivered-To: patch@linaro.org Received: by 2002:a92:4782:0:0:0:0:0 with SMTP id e2csp6962535ilk; Mon, 8 Jul 2019 03:27:24 -0700 (PDT) X-Google-Smtp-Source: APXvYqyiOf9Fdm8LxvFWh2Z+lsGMyM5UkL1Ct/BXemf/eudce/1kuGTL6HUlvQx9w6FR2b2JGFME X-Received: by 2002:a63:c24d:: with SMTP id l13mr22959256pgg.330.1562581644550; Mon, 08 Jul 2019 03:27:24 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1562581644; cv=none; d=google.com; s=arc-20160816; b=zpeFM+AcdXz2fGluo0t1BC1IB4e+PysDOR3K+RDbJmWYGTH10jWLZRJr6KG7CIOC3f iYGaQC3n2Qs40plRpJITNE2r3HzSzaWrYFoiHQRevcMBzQZod9oITGHvsz1xlsAMxsuk tsZ9GDcek7HQtGlV0z36twx91X8ebe9gEj0roneLcWWPrCcQf7b0FqhUujHavlml7LN8 I6OeGcdLzqP3X1ORYa6HMxjrpp9yLnrOSZirCOlpsfDcUM9lKkjVTyhCveyMdqBmJB4Z yceI6OGt3Iz2uzdDAfem9wp4l2jAq2XRskzEuNL1106zt1/3Oy5oBbej4q0FxwK4yOYj VHSQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=sender:errors-to:content-transfer-encoding:cc:list-subscribe :list-help:list-post:list-archive:list-unsubscribe:list-id :precedence:mime-version:references:in-reply-to:message-id:date :subject:to:from:delivered-to; bh=LoulTB5VbONSvy8WQY2KtVgN71lrqT7STSXuZvjx/ow=; b=re1A4/1+3Sa5KjNYxHCgbb5RxRkAJBr95sfDHHbJf8H+skwc1cbet5XxAB9MQeFBy/ wJ7isVWLZEafhP2Rp0PkHGE4TxOm5yNUSbtBPjNjSwEh9acM9j7ppo1uuE9mb4BjFnuV rwj3emg1+iABt1DufCNRtASl+hMXxsdiGYfK60Gah0H3UNcCchzNYyQCMs59Sz/RbWyq 8z8pLrjOyI/9OuLG+QjPl1SmkNTVEcbUndXxxa92aMqhJGCeo1sPPRWKWv9ueY3TkQHB D+E/INC/JLZC/eCY57KrBlujZBv8zE9W8oFhFPyFlmVEJ0WQ+clTbYO1K6RW/MHSGj/g 422A== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of dri-devel-bounces@lists.freedesktop.org designates 2610:10:20:722:a800:ff:fe36:1795 as permitted sender) smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org; dmarc=fail (p=QUARANTINE sp=NONE dis=QUARANTINE) header.from=ti.com Return-Path: Received: from gabe.freedesktop.org (gabe.freedesktop.org. [2610:10:20:722:a800:ff:fe36:1795]) by mx.google.com with ESMTPS id e25si19259325pff.30.2019.07.08.03.27.24 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 08 Jul 2019 03:27:24 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of dri-devel-bounces@lists.freedesktop.org designates 2610:10:20:722:a800:ff:fe36:1795 as permitted sender) client-ip=2610:10:20:722:a800:ff:fe36:1795; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of dri-devel-bounces@lists.freedesktop.org designates 2610:10:20:722:a800:ff:fe36:1795 as permitted sender) smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org; dmarc=fail (p=QUARANTINE sp=NONE dis=QUARANTINE) header.from=ti.com Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id AF66089C6A; Mon, 8 Jul 2019 10:27:18 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from lelv0142.ext.ti.com (lelv0142.ext.ti.com [198.47.23.249]) by gabe.freedesktop.org (Postfix) with ESMTPS id 7624D89C63 for ; Mon, 8 Jul 2019 10:27:17 +0000 (UTC) Received: from fllv0035.itg.ti.com ([10.64.41.0]) by lelv0142.ext.ti.com (8.15.2/8.15.2) with ESMTP id x68ARCKE001167; Mon, 8 Jul 2019 05:27:12 -0500 Received: from DLEE114.ent.ti.com (dlee114.ent.ti.com [157.170.170.25]) by fllv0035.itg.ti.com (8.15.2/8.15.2) with ESMTPS id x68ARCXK067712 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 8 Jul 2019 05:27:12 -0500 Received: from DLEE103.ent.ti.com (157.170.170.33) by DLEE114.ent.ti.com (157.170.170.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5; Mon, 8 Jul 2019 05:27:12 -0500 Received: from fllv0040.itg.ti.com (10.64.41.20) by DLEE103.ent.ti.com (157.170.170.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5 via Frontend Transport; Mon, 8 Jul 2019 05:27:12 -0500 Received: from localhost (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0040.itg.ti.com (8.15.2/8.15.2) with ESMTP id x68ARBBD074756; Mon, 8 Jul 2019 05:27:11 -0500 From: Jean-Jacques Hiblot To: , , , , , , Subject: [PATCH v2 4/4] backlight: add led-backlight driver Date: Mon, 8 Jul 2019 12:27:00 +0200 Message-ID: <20190708102700.23138-5-jjhiblot@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190708102700.23138-1-jjhiblot@ti.com> References: <20190708102700.23138-1-jjhiblot@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1562581632; bh=rsEOI56jQUV/QiIXLNiFABw3GYyB7YCOM03aYJBNebY=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=IwE43AKX9lENFZKxTVI+asaWNv6oN5tvkv2zblXfDyurPb5Tzh3BpD8bm72fZGhTA b7TCwgR/y86wDVYE5di5om/pudSqGB+SaA+JteRViAeFwpCWlW2Z70SBVy26MJmpo4 osKDYo9MlhIMMDpeEOJ+g5zEt0nn1hNjHfjvKCbQ= X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, tomi.valkeinen@ti.com, dmurphy@ti.com, Jean-Jacques Hiblot , linux-leds@vger.kernel.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Tomi Valkeinen This patch adds a led-backlight driver (led_bl), which is similar to pwm_bl except the driver uses a LED class driver to adjust the brightness in the HW. Multiple LEDs can be used for a single backlight. Signed-off-by: Tomi Valkeinen Signed-off-by: Jean-Jacques Hiblot --- drivers/video/backlight/Kconfig | 7 + drivers/video/backlight/Makefile | 1 + drivers/video/backlight/led_bl.c | 235 +++++++++++++++++++++++++++++++ 3 files changed, 243 insertions(+) create mode 100644 drivers/video/backlight/led_bl.c diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index 8b081d61773e..585a1787618c 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig @@ -458,6 +458,13 @@ config BACKLIGHT_RAVE_SP help Support for backlight control on RAVE SP device. +config BACKLIGHT_LED + tristate "Generic LED based Backlight Driver" + depends on LEDS_CLASS && OF + help + If you have a LCD backlight adjustable by LED class driver, say Y + to enable this driver. + endif # BACKLIGHT_CLASS_DEVICE endmenu diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile index 63c507c07437..2a67642966a5 100644 --- a/drivers/video/backlight/Makefile +++ b/drivers/video/backlight/Makefile @@ -57,3 +57,4 @@ obj-$(CONFIG_BACKLIGHT_TPS65217) += tps65217_bl.o obj-$(CONFIG_BACKLIGHT_WM831X) += wm831x_bl.o obj-$(CONFIG_BACKLIGHT_ARCXCNN) += arcxcnn_bl.o obj-$(CONFIG_BACKLIGHT_RAVE_SP) += rave-sp-backlight.o +obj-$(CONFIG_BACKLIGHT_LED) += led_bl.o diff --git a/drivers/video/backlight/led_bl.c b/drivers/video/backlight/led_bl.c new file mode 100644 index 000000000000..7644277cfdbb --- /dev/null +++ b/drivers/video/backlight/led_bl.c @@ -0,0 +1,235 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2015-2019 Texas Instruments Incorporated - http://www.ti.com/ + * Author: Tomi Valkeinen + * + * Based on pwm_bl.c + */ + +#include +#include +#include +#include +#include +#include + +#define BKL_FULL_BRIGHTNESS 255 + +struct led_bl_data { + struct device *dev; + struct backlight_device *bl_dev; + struct led_classdev **leds; + bool enabled; + int nb_leds; + unsigned int *levels; + unsigned int default_brightness; + unsigned int max_brightness; +}; + +static int to_led_brightness(struct led_classdev *led, int value) +{ + return (value * led->max_brightness) / BKL_FULL_BRIGHTNESS; +} + +static void led_bl_set_brightness(struct led_bl_data *priv, int level) +{ + int i; + int bkl_brightness; + + if (priv->levels) + bkl_brightness = priv->levels[level]; + else + bkl_brightness = level; + + for (i = 0; i < priv->nb_leds; i++) { + int led_brightness; + struct led_classdev *led = priv->leds[i]; + + led_brightness = to_led_brightness(led, bkl_brightness); + led_set_brightness(led, led_brightness); + } + + priv->enabled = true; +} + +static void led_bl_power_off(struct led_bl_data *priv) +{ + int i; + + if (!priv->enabled) + return; + + for (i = 0; i < priv->nb_leds; i++) + led_set_brightness(priv->leds[i], LED_OFF); + + priv->enabled = false; +} + +static int led_bl_update_status(struct backlight_device *bl) +{ + struct led_bl_data *priv = bl_get_data(bl); + int brightness = bl->props.brightness; + + if (bl->props.power != FB_BLANK_UNBLANK || + bl->props.fb_blank != FB_BLANK_UNBLANK || + bl->props.state & BL_CORE_FBBLANK) + brightness = 0; + + if (brightness > 0) + led_bl_set_brightness(priv, brightness); + else + led_bl_power_off(priv); + + return 0; +} + +static const struct backlight_ops led_bl_ops = { + .update_status = led_bl_update_status, +}; + +static int led_bl_parse_dt(struct device *dev, + struct led_bl_data *priv) +{ + struct device_node *node = dev->of_node; + int num_levels; + u32 *levels = NULL; + u32 value; + int ret; + bool use_default_levels = false; + + if (!node) + return -ENODEV; + + num_levels = of_property_count_u32_elems(node, "brightness-levels"); + if (num_levels < 0) { + dev_warn(dev, "can't get brightness-levels. using default levels\n"); + use_default_levels = true; + num_levels = BKL_FULL_BRIGHTNESS + 1; + } + + if (!use_default_levels) { + levels = devm_kzalloc(dev, sizeof(u32) * num_levels, + GFP_KERNEL); + if (!levels) + return -ENOMEM; + + ret = of_property_read_u32_array(node, "brightness-levels", + levels, + num_levels); + if (ret < 0) + return ret; + } + + ret = of_property_read_u32(node, "default-brightness-level", &value); + if (ret < 0) + value = num_levels / 2; + + if (value >= num_levels) { + dev_warn(dev, "invalid default-brightness-level. using default\n"); + value = num_levels / 2; + } + + ret = of_count_phandle_with_args(node, "leds", NULL); + if (ret < 0) { + dev_err(dev, "unable to get led count\n"); + return -EINVAL; + } + + priv->nb_leds = ret; + if (priv->nb_leds < 1) { + dev_err(dev, "At least one LED must be specified!\n"); + return -EINVAL; + } + + priv->levels = levels; + priv->max_brightness = num_levels - 1; + priv->default_brightness = value; + + return 0; +} + +static int led_bl_probe(struct platform_device *pdev) +{ + struct backlight_properties props; + struct led_bl_data *priv; + int ret; + int i; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + platform_set_drvdata(pdev, priv); + + priv->dev = &pdev->dev; + + ret = led_bl_parse_dt(&pdev->dev, priv); + if (ret < 0) { + dev_err(&pdev->dev, "failed to parse DT data\n"); + return ret; + } + priv->leds = devm_kzalloc(&pdev->dev, + sizeof(struct led_classdev *) * priv->nb_leds, + GFP_KERNEL); + if (!priv->leds) + return -ENOMEM; + + for (i = 0; i < priv->nb_leds; i++) { + priv->leds[i] = devm_led_get(&pdev->dev, i); + if (IS_ERR(priv->leds[i])) + return PTR_ERR(priv->leds[i]); + } + + memset(&props, 0, sizeof(struct backlight_properties)); + props.type = BACKLIGHT_RAW; + props.max_brightness = priv->max_brightness; + priv->bl_dev = backlight_device_register(dev_name(&pdev->dev), + &pdev->dev, priv, &led_bl_ops, &props); + if (IS_ERR(priv->bl_dev)) { + dev_err(&pdev->dev, "failed to register backlight\n"); + ret = PTR_ERR(priv->bl_dev); + goto err; + } + + priv->bl_dev->props.brightness = priv->default_brightness; + backlight_update_status(priv->bl_dev); + + return 0; + +err: + return ret; +} + +static int led_bl_remove(struct platform_device *pdev) +{ + struct led_bl_data *priv = platform_get_drvdata(pdev); + struct backlight_device *bl = priv->bl_dev; + + backlight_device_unregister(bl); + + led_bl_power_off(priv); + + return 0; +} + +static const struct of_device_id led_bl_of_match[] = { + { .compatible = "led-backlight" }, + { } +}; + +MODULE_DEVICE_TABLE(of, led_bl_of_match); + +static struct platform_driver led_bl_driver = { + .driver = { + .name = "led-backlight", + .of_match_table = of_match_ptr(led_bl_of_match), + }, + .probe = led_bl_probe, + .remove = led_bl_remove, +}; + +module_platform_driver(led_bl_driver); + +MODULE_DESCRIPTION("LED based Backlight Driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:led-backlight");