1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Backlight Driver for Dialog DA9052 PMICs
5 * Copyright(c) 2012 Dialog Semiconductor Ltd.
7 * Author: David Dajun Chen <dchen@diasemi.com>
10 #include <linux/backlight.h>
11 #include <linux/delay.h>
13 #include <linux/module.h>
14 #include <linux/platform_device.h>
16 #include <linux/mfd/da9052/da9052.h>
17 #include <linux/mfd/da9052/reg.h>
19 #define DA9052_MAX_BRIGHTNESS 0xFF
32 static const unsigned char wled_bank[] = {
39 struct da9052 *da9052;
45 static int da9052_adjust_wled_brightness(struct da9052_bl *wleds)
47 unsigned char boost_en;
53 if (wleds->state == DA9052_WLEDS_OFF) {
58 ret = da9052_reg_write(wleds->da9052, DA9052_BOOST_REG, boost_en);
62 ret = da9052_reg_write(wleds->da9052, DA9052_LED_CONT_REG, i_sink);
66 ret = da9052_reg_write(wleds->da9052, wled_bank[wleds->led_reg], 0x0);
70 usleep_range(10000, 11000);
72 if (wleds->brightness) {
73 ret = da9052_reg_write(wleds->da9052, wled_bank[wleds->led_reg],
82 static int da9052_backlight_update_status(struct backlight_device *bl)
84 int brightness = bl->props.brightness;
85 struct da9052_bl *wleds = bl_get_data(bl);
87 wleds->brightness = brightness;
88 wleds->state = DA9052_WLEDS_ON;
90 return da9052_adjust_wled_brightness(wleds);
93 static int da9052_backlight_get_brightness(struct backlight_device *bl)
95 struct da9052_bl *wleds = bl_get_data(bl);
97 return wleds->brightness;
100 static const struct backlight_ops da9052_backlight_ops = {
101 .update_status = da9052_backlight_update_status,
102 .get_brightness = da9052_backlight_get_brightness,
105 static int da9052_backlight_probe(struct platform_device *pdev)
107 struct backlight_device *bl;
108 struct backlight_properties props;
109 struct da9052_bl *wleds;
111 wleds = devm_kzalloc(&pdev->dev, sizeof(struct da9052_bl), GFP_KERNEL);
115 wleds->da9052 = dev_get_drvdata(pdev->dev.parent);
116 wleds->brightness = 0;
117 wleds->led_reg = platform_get_device_id(pdev)->driver_data;
118 wleds->state = DA9052_WLEDS_OFF;
120 memset(&props, 0, sizeof(struct backlight_properties));
121 props.type = BACKLIGHT_RAW;
122 props.max_brightness = DA9052_MAX_BRIGHTNESS;
124 bl = devm_backlight_device_register(&pdev->dev, pdev->name,
125 wleds->da9052->dev, wleds,
126 &da9052_backlight_ops, &props);
128 dev_err(&pdev->dev, "Failed to register backlight\n");
132 bl->props.max_brightness = DA9052_MAX_BRIGHTNESS;
133 bl->props.brightness = 0;
134 platform_set_drvdata(pdev, bl);
136 return da9052_adjust_wled_brightness(wleds);
139 static int da9052_backlight_remove(struct platform_device *pdev)
141 struct backlight_device *bl = platform_get_drvdata(pdev);
142 struct da9052_bl *wleds = bl_get_data(bl);
144 wleds->brightness = 0;
145 wleds->state = DA9052_WLEDS_OFF;
146 da9052_adjust_wled_brightness(wleds);
151 static const struct platform_device_id da9052_wled_ids[] = {
153 .name = "da9052-wled1",
154 .driver_data = DA9052_TYPE_WLED1,
157 .name = "da9052-wled2",
158 .driver_data = DA9052_TYPE_WLED2,
161 .name = "da9052-wled3",
162 .driver_data = DA9052_TYPE_WLED3,
166 MODULE_DEVICE_TABLE(platform, da9052_wled_ids);
168 static struct platform_driver da9052_wled_driver = {
169 .probe = da9052_backlight_probe,
170 .remove = da9052_backlight_remove,
171 .id_table = da9052_wled_ids,
173 .name = "da9052-wled",
177 module_platform_driver(da9052_wled_driver);
179 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
180 MODULE_DESCRIPTION("Backlight driver for DA9052 PMIC");
181 MODULE_LICENSE("GPL");