From patchwork Fri Oct 20 13:54:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Flavio Suligoi X-Patchwork-Id: 736497 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 91A83C25B40 for ; Fri, 20 Oct 2023 13:55:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377509AbjJTNzQ (ORCPT ); Fri, 20 Oct 2023 09:55:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55004 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1377495AbjJTNzN (ORCPT ); Fri, 20 Oct 2023 09:55:13 -0400 Received: from EUR04-DB3-obe.outbound.protection.outlook.com (mail-db3eur04on2059.outbound.protection.outlook.com [40.107.6.59]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F1A7CCA; Fri, 20 Oct 2023 06:55:08 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=R2gNM+tU8WuIbOvGxw0juPV8J0o0eeRfJH2nv3OLqzRKXNPX8mW7AeGsdDpR08s6uX14PxJVN2jKjvXgpVLXt9ZOXSILu6cxevNXviwiGQCzABHRn2CIngy/MLHbjegJSqgY7W7T6SwI6SM51y0/kpcE5EIglvUlvZDmNmv5WxNDiS9+jvq7DQ5QL5Ykcgzyy1Zqg469yARZp0N4sryvDbC1gN8SHrhvt4dhmzljAjMrG3GZaOv6asziS/e0MgAH2fpUOU0m+DaeX1WrHR5bE6VY/S1EdS3Hk37ti2c5R40gVzGojRsVdr71kTWBw/Vhwcy3OvuddNOIYdsff6qNDA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=PFXl+hbTrARvbVJiKhYP8TvK7ygcDX0KwXZ3KkhJrgg=; b=fMrquEw0C4BINqIaPPMyY84wClkm/QZaj2LnA8GPvwoOCZyY3fmiNrPQAyk2nMYM057eJjdZwabfmzp3j5ECNOMHAbwEmn2wz2VeFkL3P+miKEkIyKaZjmX/mQAARtKwo17cPlUo+NcszJVQ2cK5QG7x0O0ZhkO/NxV+3ZOp5RV6qIv8yR5Vl6UfRbd1y4oJA+ejBLxx0RsACaxRhmyNRjuXvy9KR/V0euVGg7GNESMUgOqBUw+FdBwKC1QWtyLSXk0nhUC1Pg27+Tzxc/DjSypJFyMOKCsZ+SrwW6tX+4aVOvV4JepNRvzLyQc80+p7xYZL7KBWEeHOMPqf3NzGUw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=softfail (sender ip is 151.1.184.193) smtp.rcpttodomain=vger.kernel.org smtp.mailfrom=asem.it; dmarc=fail (p=none sp=none pct=100) action=none header.from=asem.it; dkim=none (message not signed); arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=asem.it; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=PFXl+hbTrARvbVJiKhYP8TvK7ygcDX0KwXZ3KkhJrgg=; b=VVbcIlDrkbQAbjvgMzRc6tL/5mDs4Ao9giUAw6BOC7VmJClDxW1FbBrCW3oPz3Uj27ycPKPCLwrmMZ1SbUC82tBlpS9hUz12fPErA7Jx3rxLoSSoFw8pbHz//w0caTshk1zGmL4Am5qmsdtqkk/GEUcChYKOPx9t/V+Ju5AtEJc= Received: from DU2PR04CA0023.eurprd04.prod.outlook.com (2603:10a6:10:3b::28) by DB9PR01MB9438.eurprd01.prod.exchangelabs.com (2603:10a6:10:362::12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6907.26; Fri, 20 Oct 2023 13:55:05 +0000 Received: from DU6PEPF0000B622.eurprd02.prod.outlook.com (2603:10a6:10:3b:cafe::5a) by DU2PR04CA0023.outlook.office365.com (2603:10a6:10:3b::28) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6907.26 via Frontend Transport; Fri, 20 Oct 2023 13:55:05 +0000 X-MS-Exchange-Authentication-Results: spf=softfail (sender IP is 151.1.184.193) smtp.mailfrom=asem.it; dkim=none (message not signed) header.d=none;dmarc=fail action=none header.from=asem.it; Received-SPF: SoftFail (protection.outlook.com: domain of transitioning asem.it discourages use of 151.1.184.193 as permitted sender) Received: from asas054.asem.intra (151.1.184.193) by DU6PEPF0000B622.mail.protection.outlook.com (10.167.8.139) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6907.20 via Frontend Transport; Fri, 20 Oct 2023 13:55:05 +0000 Received: from flavio-x.asem.intra ([172.16.18.47]) by asas054.asem.intra with Microsoft SMTPSVC(10.0.14393.4169); Fri, 20 Oct 2023 15:55:02 +0200 From: Flavio Suligoi To: Lee Jones , Daniel Thompson , Jingoo Han , Helge Deller , Pavel Machek , Rob Herring , Krzysztof Kozlowski , Conor Dooley Cc: dri-devel@lists.freedesktop.org, linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, Flavio Suligoi Subject: [PATCH v5] backlight: mp3309c: Add support for MPS MP3309C Date: Fri, 20 Oct 2023 15:54:34 +0200 Message-Id: <20231020135434.2598578-3-f.suligoi@asem.it> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231020135434.2598578-1-f.suligoi@asem.it> References: <20231020135434.2598578-1-f.suligoi@asem.it> MIME-Version: 1.0 X-OriginalArrivalTime: 20 Oct 2023 13:55:02.0844 (UTC) FILETIME=[060147C0:01DA035D] X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DU6PEPF0000B622:EE_|DB9PR01MB9438:EE_ X-MS-Office365-Filtering-Correlation-Id: c9c94bb0-b455-4c18-3990-08dbd17429fc X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:151.1.184.193; CTRY:IT; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:asas054.asem.intra; PTR:InfoDomainNonexistent; CAT:NONE; SFS:(13230031)(136003)(376002)(346002)(396003)(39850400004)(230922051799003)(186009)(1800799009)(451199024)(64100799003)(82310400011)(46966006)(36840700001)(36860700001)(83380400001)(1076003)(26005)(336012)(6666004)(107886003)(86362001)(47076005)(36756003)(356005)(82740400003)(81166007)(2616005)(966005)(4326008)(41300700001)(8936002)(8676002)(478600001)(5660300002)(450100002)(30864003)(2906002)(40480700001)(110136005)(316002)(70586007)(70206006)(36900700001); DIR:OUT; SFP:1101; X-OriginatorOrg: asem.it X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Oct 2023 13:55:05.1676 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: c9c94bb0-b455-4c18-3990-08dbd17429fc X-MS-Exchange-CrossTenant-Id: d0a766c6-7992-4344-a4a2-a467a7bb1ed2 X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=d0a766c6-7992-4344-a4a2-a467a7bb1ed2; Ip=[151.1.184.193]; Helo=[asas054.asem.intra] X-MS-Exchange-CrossTenant-AuthSource: DU6PEPF0000B622.eurprd02.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB9PR01MB9438 Precedence: bulk List-ID: X-Mailing-List: linux-leds@vger.kernel.org The Monolithic Power (MPS) MP3309C is a WLED step-up converter, featuring a programmable switching frequency to optimize efficiency. The brightness can be controlled either by I2C commands (called "analog" mode) or by a PWM input signal (PWM mode). This driver supports both modes. For DT configuration details, please refer to: - Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml The datasheet is available at: - https://www.monolithicpower.com/en/mp3309c.html Signed-off-by: Flavio Suligoi --- v5: - checked and resend for updated kernel 6.6.0-rc1 v4: - add brightness-levels property - force fixed 32 brightness levels (0..31) in analog-i2c dimming mode - remove useless irq and reset_gpio from mp3309c_chip structure v3: - fix SPDX obsolete spelling - in mp3309c_bl_update_status, change from msleep_interruptible() to msleep() and improve the related comment v2: - fix dependecies in Kconfig - fix Kconfig MP3309C entry order - remove switch-on-delay-ms property - remove optional gpio property to reset external devices - remove dimming-mode property (the analog-i2c dimming mode is the default; the presence of the pwms property, in DT, selects automatically the pwm dimming mode) - substitute three boolean properties, used for the overvoltage-protection values, with a single enum property - drop simple tracing messages - use dev_err_probe() in probe function - change device name from mp3309c_bl to the simple mp3309c - remove shutdown function v1: - first version MAINTAINERS | 7 + drivers/video/backlight/Kconfig | 11 + drivers/video/backlight/Makefile | 1 + drivers/video/backlight/mp3309c.c | 443 ++++++++++++++++++++++++++++++ 4 files changed, 462 insertions(+) create mode 100644 drivers/video/backlight/mp3309c.c diff --git a/MAINTAINERS b/MAINTAINERS index 90f13281d297..3d23b869e2aa 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -14474,6 +14474,13 @@ S: Maintained F: Documentation/driver-api/tty/moxa-smartio.rst F: drivers/tty/mxser.* +MP3309C BACKLIGHT DRIVER +M: Flavio Suligoi +L: dri-devel@lists.freedesktop.org +S: Maintained +F: Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml +F: drivers/video/backlight/mp3309c.c + MR800 AVERMEDIA USB FM RADIO DRIVER M: Alexey Klimov L: linux-media@vger.kernel.org diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index 51387b1ef012..1144a54a35c0 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig @@ -402,6 +402,17 @@ config BACKLIGHT_LP8788 help This supports TI LP8788 backlight driver. +config BACKLIGHT_MP3309C + tristate "Backlight Driver for MPS MP3309C" + depends on I2C && PWM + select REGMAP_I2C + help + This supports MPS MP3309C backlight WLED driver in both PWM and + analog/I2C dimming modes. + + To compile this driver as a module, choose M here: the module will + be called mp3309c. + config BACKLIGHT_PANDORA tristate "Backlight driver for Pandora console" depends on TWL4030_CORE diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile index f72e1c3c59e9..1af583de665b 100644 --- a/drivers/video/backlight/Makefile +++ b/drivers/video/backlight/Makefile @@ -44,6 +44,7 @@ obj-$(CONFIG_BACKLIGHT_LP855X) += lp855x_bl.o obj-$(CONFIG_BACKLIGHT_LP8788) += lp8788_bl.o obj-$(CONFIG_BACKLIGHT_LV5207LP) += lv5207lp.o obj-$(CONFIG_BACKLIGHT_MAX8925) += max8925_bl.o +obj-$(CONFIG_BACKLIGHT_MP3309C) += mp3309c.o obj-$(CONFIG_BACKLIGHT_MT6370) += mt6370-backlight.o obj-$(CONFIG_BACKLIGHT_OMAP1) += omap1_bl.o obj-$(CONFIG_BACKLIGHT_PANDORA) += pandora_bl.o diff --git a/drivers/video/backlight/mp3309c.c b/drivers/video/backlight/mp3309c.c new file mode 100644 index 000000000000..3fe4469ef43f --- /dev/null +++ b/drivers/video/backlight/mp3309c.c @@ -0,0 +1,443 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for MPS MP3309C White LED driver with I2C interface + * + * This driver support both analog (by I2C commands) and PWM dimming control + * modes. + * + * Copyright (C) 2023 ASEM Srl + * Author: Flavio Suligoi + * + * Based on pwm_bl.c + */ + +#include +#include +#include +#include +#include +#include + +#define REG_I2C_0 0x00 +#define REG_I2C_1 0x01 + +#define REG_I2C_0_EN 0x80 +#define REG_I2C_0_D0 0x40 +#define REG_I2C_0_D1 0x20 +#define REG_I2C_0_D2 0x10 +#define REG_I2C_0_D3 0x08 +#define REG_I2C_0_D4 0x04 +#define REG_I2C_0_RSRV1 0x02 +#define REG_I2C_0_RSRV2 0x01 + +#define REG_I2C_1_RSRV1 0x80 +#define REG_I2C_1_DIMS 0x40 +#define REG_I2C_1_SYNC 0x20 +#define REG_I2C_1_OVP0 0x10 +#define REG_I2C_1_OVP1 0x08 +#define REG_I2C_1_VOS 0x04 +#define REG_I2C_1_LEDO 0x02 +#define REG_I2C_1_OTP 0x01 + +#define ANALOG_I2C_NUM_LEVELS 32 /* 0..31 */ +#define ANALOG_I2C_REG_MASK 0x7c + +#define MP3309C_PWM_DEFAULT_NUM_LEVELS 256 /* 0..255 */ + +enum mp3309c_status_value { + FIRST_POWER_ON, + BACKLIGHT_OFF, + BACKLIGHT_ON, +}; + +enum mp3309c_dimming_mode_value { + DIMMING_PWM, + DIMMING_ANALOG_I2C, +}; + +struct mp3309c_platform_data { + unsigned int max_brightness; + unsigned int default_brightness; + unsigned int *levels; + u8 dimming_mode; + u8 over_voltage_protection; + bool sync_mode; + u8 status; +}; + +struct mp3309c_chip { + struct device *dev; + struct mp3309c_platform_data *pdata; + struct backlight_device *bl; + struct gpio_desc *enable_gpio; + struct regmap *regmap; + struct pwm_device *pwmd; +}; + +static const struct regmap_config mp3309c_regmap = { + .name = "mp3309c_regmap", + .reg_bits = 8, + .reg_stride = 1, + .val_bits = 8, + .max_register = REG_I2C_1, +}; + +static int mp3309c_enable_device(struct mp3309c_chip *chip) +{ + u8 reg_val; + int ret; + + /* I2C register #0 - Device enable */ + ret = regmap_update_bits(chip->regmap, REG_I2C_0, REG_I2C_0_EN, + REG_I2C_0_EN); + if (ret) + return ret; + + /* + * I2C register #1 - Set working mode: + * - set one of the two dimming mode: + * - PWM dimming using an external PWM dimming signal + * - analog dimming using I2C commands + * - enable/disable synchronous mode + * - set overvoltage protection (OVP) + */ + reg_val = 0x00; + if (chip->pdata->dimming_mode == DIMMING_PWM) + reg_val |= REG_I2C_1_DIMS; + if (chip->pdata->sync_mode) + reg_val |= REG_I2C_1_SYNC; + reg_val |= chip->pdata->over_voltage_protection; + ret = regmap_write(chip->regmap, REG_I2C_1, reg_val); + if (ret) + return ret; + + return 0; +} + +static int mp3309c_bl_update_status(struct backlight_device *bl) +{ + struct mp3309c_chip *chip = bl_get_data(bl); + int brightness = backlight_get_brightness(bl); + struct pwm_state pwmstate; + unsigned int analog_val, bits_val; + int i, ret; + + if (chip->pdata->dimming_mode == DIMMING_PWM) { + /* + * PWM control mode + */ + pwm_get_state(chip->pwmd, &pwmstate); + pwm_set_relative_duty_cycle(&pwmstate, + chip->pdata->levels[brightness], + chip->pdata->levels[chip->pdata->max_brightness]); + pwmstate.enabled = true; + ret = pwm_apply_state(chip->pwmd, &pwmstate); + if (ret) + return ret; + + switch (chip->pdata->status) { + case FIRST_POWER_ON: + case BACKLIGHT_OFF: + /* + * After 20ms of low pwm signal level, the chip turns + * off automatically. In this case, before enabling the + * chip again, we must wait about 10ms for pwm signal to + * stabilize. + */ + if (brightness > 0) { + msleep(10); + mp3309c_enable_device(chip); + chip->pdata->status = BACKLIGHT_ON; + } else { + chip->pdata->status = BACKLIGHT_OFF; + } + break; + case BACKLIGHT_ON: + if (brightness == 0) + chip->pdata->status = BACKLIGHT_OFF; + break; + } + } else { + /* + * Analog (by I2C command) control mode + * + * The first time, before setting brightness, we must enable the + * device + */ + if (chip->pdata->status == FIRST_POWER_ON) + mp3309c_enable_device(chip); + + /* + * Dimming mode I2C command (fixed dimming range 0..31) + * + * The 5 bits of the dimming analog value D4..D0 is allocated + * in the I2C register #0, in the following way: + * + * +--+--+--+--+--+--+--+--+ + * |EN|D0|D1|D2|D3|D4|XX|XX| + * +--+--+--+--+--+--+--+--+ + */ + analog_val = brightness; + bits_val = 0; + for (i = 0; i <= 5; i++) + bits_val += ((analog_val >> i) & 0x01) << (6 - i); + ret = regmap_update_bits(chip->regmap, REG_I2C_0, + ANALOG_I2C_REG_MASK, bits_val); + if (ret) + return ret; + + if (brightness > 0) + chip->pdata->status = BACKLIGHT_ON; + else + chip->pdata->status = BACKLIGHT_OFF; + } + + return 0; +} + +static const struct backlight_ops mp3309c_bl_ops = { + .update_status = mp3309c_bl_update_status, +}; + +static int pm3309c_parse_dt_node(struct mp3309c_chip *chip, + struct mp3309c_platform_data *pdata) +{ + struct device_node *node = chip->dev->of_node; + struct property *prop_pwms, *prop_levels; + int length = 0; + int ret, i; + unsigned int num_levels, tmp_value; + + if (!node) { + dev_err(chip->dev, "failed to get DT node\n"); + return -ENODEV; + } + + /* + * Dimming mode: the MP3309C provides two dimming control mode: + * + * - PWM mode + * - Analog by I2C control mode (default) + * + * I2C control mode is assumed as default but, if the pwms property is + * found in the backlight node, the mode switches to PWM mode. + */ + pdata->dimming_mode = DIMMING_ANALOG_I2C; + prop_pwms = of_find_property(node, "pwms", &length); + if (prop_pwms) { + chip->pwmd = devm_pwm_get(chip->dev, NULL); + if (IS_ERR(chip->pwmd)) + return dev_err_probe(chip->dev, PTR_ERR(chip->pwmd), + "error getting pwm data\n"); + pdata->dimming_mode = DIMMING_PWM; + pwm_apply_args(chip->pwmd); + } + + /* + * In I2C control mode the dimming levels (0..31) are fixed by the + * hardware, while in PWM control mode they can be chosen by the user, + * to allow nonlinear mappings. + */ + if (pdata->dimming_mode == DIMMING_ANALOG_I2C) { + /* + * Analog (by I2C commands) control mode: fixed 0..31 brightness + * levels + */ + num_levels = ANALOG_I2C_NUM_LEVELS; + + /* Enable GPIO used in I2C dimming mode only */ + chip->enable_gpio = devm_gpiod_get(chip->dev, "enable", + GPIOD_OUT_HIGH); + if (IS_ERR(chip->enable_gpio)) + return dev_err_probe(chip->dev, + PTR_ERR(chip->enable_gpio), + "error getting enable gpio\n"); + } else { + /* + * PWM control mode: check for brightness level in DT + */ + prop_levels = of_find_property(node, "brightness-levels", + &length); + if (prop_levels) { + /* Read brightness levels from DT */ + num_levels = length / sizeof(u32); + if (num_levels < 2) + return -EINVAL; + } else { + /* Use default brightness levels */ + num_levels = MP3309C_PWM_DEFAULT_NUM_LEVELS; + } + } + + /* Fill brightness levels array */ + pdata->levels = devm_kcalloc(chip->dev, num_levels, + sizeof(*pdata->levels), GFP_KERNEL); + if (!pdata->levels) + return -ENOMEM; + if (prop_levels) { + ret = of_property_read_u32_array(node, "brightness-levels", + pdata->levels, + num_levels); + if (ret < 0) + return ret; + } else { + for (i = 0; i < num_levels; i++) + pdata->levels[i] = i; + } + + pdata->max_brightness = num_levels - 1; + + ret = of_property_read_u32(node, "default-brightness", + &pdata->default_brightness); + if (ret) + pdata->default_brightness = pdata->max_brightness; + if (pdata->default_brightness > pdata->max_brightness) { + dev_err(chip->dev, + "default brightness exceeds max brightness\n"); + pdata->default_brightness = pdata->max_brightness; + } + + /* + * Over-voltage protection (OVP) + * + * This (optional) property values are: + * + * - 13.5V + * - 24V + * - 35.5V (hardware default setting) + * + * If missing, the default value for OVP is 35.5V + */ + pdata->over_voltage_protection = REG_I2C_1_OVP1; + if (!of_property_read_u32(node, "mps,overvoltage-protection-microvolt", + &tmp_value)) { + switch (tmp_value) { + case 13500000: + pdata->over_voltage_protection = 0x00; + break; + case 24000000: + pdata->over_voltage_protection = REG_I2C_1_OVP0; + break; + case 35500000: + pdata->over_voltage_protection = REG_I2C_1_OVP1; + break; + default: + return -EINVAL; + } + } + + /* Synchronous (default) and non-synchronous mode */ + pdata->sync_mode = true; + if (of_property_read_bool(node, "mps,no-sync-mode")) + pdata->sync_mode = false; + + return 0; +} + +static int mp3309c_probe(struct i2c_client *client) +{ + struct mp3309c_platform_data *pdata = dev_get_platdata(&client->dev); + struct mp3309c_chip *chip; + struct backlight_properties props; + struct pwm_state pwmstate; + int ret; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + dev_err(&client->dev, "failed to check i2c functionality\n"); + return -EOPNOTSUPP; + } + + chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + chip->dev = &client->dev; + + chip->regmap = devm_regmap_init_i2c(client, &mp3309c_regmap); + if (IS_ERR(chip->regmap)) + return dev_err_probe(&client->dev, PTR_ERR(chip->regmap), + "failed to allocate register map\n"); + + i2c_set_clientdata(client, chip); + + if (!pdata) { + pdata = devm_kzalloc(chip->dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return -ENOMEM; + + ret = pm3309c_parse_dt_node(chip, pdata); + if (ret) + return ret; + } + chip->pdata = pdata; + + /* Backlight properties */ + props.brightness = pdata->default_brightness; + props.max_brightness = pdata->max_brightness; + props.scale = BACKLIGHT_SCALE_LINEAR; + props.type = BACKLIGHT_RAW; + props.power = FB_BLANK_UNBLANK; + props.fb_blank = FB_BLANK_UNBLANK; + chip->bl = devm_backlight_device_register(chip->dev, "mp3309c", + chip->dev, chip, + &mp3309c_bl_ops, &props); + if (IS_ERR(chip->bl)) + return dev_err_probe(chip->dev, PTR_ERR(chip->bl), + "error registering backlight device\n"); + + /* In PWM dimming mode, enable pwm device */ + if (chip->pdata->dimming_mode == DIMMING_PWM) { + pwm_init_state(chip->pwmd, &pwmstate); + pwm_set_relative_duty_cycle(&pwmstate, + chip->pdata->default_brightness, + chip->pdata->max_brightness); + pwmstate.enabled = true; + ret = pwm_apply_state(chip->pwmd, &pwmstate); + if (ret) + return dev_err_probe(chip->dev, ret, + "error setting pwm device\n"); + } + + chip->pdata->status = FIRST_POWER_ON; + backlight_update_status(chip->bl); + + return 0; +} + +static void mp3309c_remove(struct i2c_client *client) +{ + struct mp3309c_chip *chip = i2c_get_clientdata(client); + struct backlight_device *bl = chip->bl; + + bl->props.power = FB_BLANK_POWERDOWN; + bl->props.brightness = 0; + backlight_update_status(chip->bl); +} + +static const struct of_device_id mp3309c_match_table[] = { + { .compatible = "mps,mp3309c", }, + { }, +}; +MODULE_DEVICE_TABLE(of, mp3309c_match_table); + +static const struct i2c_device_id mp3309c_id[] = { + { "mp3309c", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, mp3309c_id); + +static struct i2c_driver mp3309c_i2c_driver = { + .driver = { + .name = KBUILD_MODNAME, + .of_match_table = mp3309c_match_table, + }, + .probe = mp3309c_probe, + .remove = mp3309c_remove, + .id_table = mp3309c_id, +}; + +module_i2c_driver(mp3309c_i2c_driver); + +MODULE_DESCRIPTION("Backlight Driver for MPS MP3309C"); +MODULE_AUTHOR("Flavio Suligoi "); +MODULE_LICENSE("GPL");