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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Backlight driver for Dialog Semiconductor DA9030/DA90344 *5 * Copyright (C) 2008 Compulab, Ltd.6 * Mike Rapoport <mike@compulab.co.il>7 *8 * Copyright (C) 2006-2008 Marvell International Ltd.9 * Eric Miao <eric.miao@marvell.com>10 */11 12#include <linux/kernel.h>13#include <linux/init.h>14#include <linux/platform_device.h>15#include <linux/fb.h>16#include <linux/backlight.h>17#include <linux/mfd/da903x.h>18#include <linux/slab.h>19#include <linux/module.h>20 21#define DA9030_WLED_CONTROL 0x2522#define DA9030_WLED_CP_EN (1 << 6)23#define DA9030_WLED_TRIM(x) ((x) & 0x7)24 25#define DA9034_WLED_CONTROL1 0x3C26#define DA9034_WLED_CONTROL2 0x3D27#define DA9034_WLED_ISET(x) ((x) & 0x1f)28 29#define DA9034_WLED_BOOST_EN (1 << 5)30 31#define DA9030_MAX_BRIGHTNESS 732#define DA9034_MAX_BRIGHTNESS 0x7f33 34struct da903x_backlight_data {35 struct device *da903x_dev;36 int id;37 int current_brightness;38};39 40static int da903x_backlight_set(struct backlight_device *bl, int brightness)41{42 struct da903x_backlight_data *data = bl_get_data(bl);43 struct device *dev = data->da903x_dev;44 uint8_t val;45 int ret = 0;46 47 switch (data->id) {48 case DA9034_ID_WLED:49 ret = da903x_update(dev, DA9034_WLED_CONTROL1,50 brightness, 0x7f);51 if (ret)52 return ret;53 54 if (data->current_brightness && brightness == 0)55 ret = da903x_clr_bits(dev,56 DA9034_WLED_CONTROL2,57 DA9034_WLED_BOOST_EN);58 59 if (data->current_brightness == 0 && brightness)60 ret = da903x_set_bits(dev,61 DA9034_WLED_CONTROL2,62 DA9034_WLED_BOOST_EN);63 break;64 case DA9030_ID_WLED:65 val = DA9030_WLED_TRIM(brightness);66 val |= brightness ? DA9030_WLED_CP_EN : 0;67 ret = da903x_write(dev, DA9030_WLED_CONTROL, val);68 break;69 }70 71 if (ret)72 return ret;73 74 data->current_brightness = brightness;75 return 0;76}77 78static int da903x_backlight_update_status(struct backlight_device *bl)79{80 return da903x_backlight_set(bl, backlight_get_brightness(bl));81}82 83static int da903x_backlight_get_brightness(struct backlight_device *bl)84{85 struct da903x_backlight_data *data = bl_get_data(bl);86 87 return data->current_brightness;88}89 90static const struct backlight_ops da903x_backlight_ops = {91 .options = BL_CORE_SUSPENDRESUME,92 .update_status = da903x_backlight_update_status,93 .get_brightness = da903x_backlight_get_brightness,94};95 96static int da903x_backlight_probe(struct platform_device *pdev)97{98 struct da9034_backlight_pdata *pdata = dev_get_platdata(&pdev->dev);99 struct da903x_backlight_data *data;100 struct backlight_device *bl;101 struct backlight_properties props;102 int max_brightness;103 104 data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);105 if (data == NULL)106 return -ENOMEM;107 108 switch (pdev->id) {109 case DA9030_ID_WLED:110 max_brightness = DA9030_MAX_BRIGHTNESS;111 break;112 case DA9034_ID_WLED:113 max_brightness = DA9034_MAX_BRIGHTNESS;114 break;115 default:116 dev_err(&pdev->dev, "invalid backlight device ID(%d)\n",117 pdev->id);118 return -EINVAL;119 }120 121 data->id = pdev->id;122 data->da903x_dev = pdev->dev.parent;123 data->current_brightness = 0;124 125 /* adjust the WLED output current */126 if (pdata)127 da903x_write(data->da903x_dev, DA9034_WLED_CONTROL2,128 DA9034_WLED_ISET(pdata->output_current));129 130 memset(&props, 0, sizeof(props));131 props.type = BACKLIGHT_RAW;132 props.max_brightness = max_brightness;133 bl = devm_backlight_device_register(&pdev->dev, pdev->name,134 data->da903x_dev, data,135 &da903x_backlight_ops, &props);136 if (IS_ERR(bl)) {137 dev_err(&pdev->dev, "failed to register backlight\n");138 return PTR_ERR(bl);139 }140 141 bl->props.brightness = max_brightness;142 143 platform_set_drvdata(pdev, bl);144 backlight_update_status(bl);145 return 0;146}147 148static struct platform_driver da903x_backlight_driver = {149 .driver = {150 .name = "da903x-backlight",151 },152 .probe = da903x_backlight_probe,153};154 155module_platform_driver(da903x_backlight_driver);156 157MODULE_DESCRIPTION("Backlight Driver for Dialog Semiconductor DA9030/DA9034");158MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>");159MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");160MODULE_LICENSE("GPL");161MODULE_ALIAS("platform:da903x-backlight");162