2 * Backlight driver for Dialog Semiconductor DA9030/DA9034
4 * Copyright (C) 2008 Compulab, Ltd.
5 * Mike Rapoport <mike@compulab.co.il>
7 * Copyright (C) 2006-2008 Marvell International Ltd.
8 * Eric Miao <eric.miao@marvell.com>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/platform_device.h>
19 #include <linux/backlight.h>
20 #include <linux/mfd/da903x.h>
21 #include <linux/slab.h>
22 #include <linux/module.h>
24 #define DA9030_WLED_CONTROL 0x25
25 #define DA9030_WLED_CP_EN (1 << 6)
26 #define DA9030_WLED_TRIM(x) ((x) & 0x7)
28 #define DA9034_WLED_CONTROL1 0x3C
29 #define DA9034_WLED_CONTROL2 0x3D
30 #define DA9034_WLED_ISET(x) ((x) & 0x1f)
32 #define DA9034_WLED_BOOST_EN (1 << 5)
34 #define DA9030_MAX_BRIGHTNESS 7
35 #define DA9034_MAX_BRIGHTNESS 0x7f
37 struct da903x_backlight_data {
38 struct device *da903x_dev;
40 int current_brightness;
43 static int da903x_backlight_set(struct backlight_device *bl, int brightness)
45 struct da903x_backlight_data *data = bl_get_data(bl);
46 struct device *dev = data->da903x_dev;
52 ret = da903x_update(dev, DA9034_WLED_CONTROL1,
57 if (data->current_brightness && brightness == 0)
58 ret = da903x_clr_bits(dev,
60 DA9034_WLED_BOOST_EN);
62 if (data->current_brightness == 0 && brightness)
63 ret = da903x_set_bits(dev,
65 DA9034_WLED_BOOST_EN);
68 val = DA9030_WLED_TRIM(brightness);
69 val |= brightness ? DA9030_WLED_CP_EN : 0;
70 ret = da903x_write(dev, DA9030_WLED_CONTROL, val);
77 data->current_brightness = brightness;
81 static int da903x_backlight_update_status(struct backlight_device *bl)
83 int brightness = bl->props.brightness;
85 if (bl->props.power != FB_BLANK_UNBLANK)
88 if (bl->props.fb_blank != FB_BLANK_UNBLANK)
91 if (bl->props.state & BL_CORE_SUSPENDED)
94 return da903x_backlight_set(bl, brightness);
97 static int da903x_backlight_get_brightness(struct backlight_device *bl)
99 struct da903x_backlight_data *data = bl_get_data(bl);
101 return data->current_brightness;
104 static const struct backlight_ops da903x_backlight_ops = {
105 .options = BL_CORE_SUSPENDRESUME,
106 .update_status = da903x_backlight_update_status,
107 .get_brightness = da903x_backlight_get_brightness,
110 static int da903x_backlight_probe(struct platform_device *pdev)
112 struct da9034_backlight_pdata *pdata = dev_get_platdata(&pdev->dev);
113 struct da903x_backlight_data *data;
114 struct backlight_device *bl;
115 struct backlight_properties props;
118 data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
124 max_brightness = DA9030_MAX_BRIGHTNESS;
127 max_brightness = DA9034_MAX_BRIGHTNESS;
130 dev_err(&pdev->dev, "invalid backlight device ID(%d)\n",
136 data->da903x_dev = pdev->dev.parent;
137 data->current_brightness = 0;
139 /* adjust the WLED output current */
141 da903x_write(data->da903x_dev, DA9034_WLED_CONTROL2,
142 DA9034_WLED_ISET(pdata->output_current));
144 memset(&props, 0, sizeof(props));
145 props.type = BACKLIGHT_RAW;
146 props.max_brightness = max_brightness;
147 bl = backlight_device_register(pdev->name, data->da903x_dev, data,
148 &da903x_backlight_ops, &props);
150 dev_err(&pdev->dev, "failed to register backlight\n");
154 bl->props.brightness = max_brightness;
156 platform_set_drvdata(pdev, bl);
157 backlight_update_status(bl);
161 static int da903x_backlight_remove(struct platform_device *pdev)
163 struct backlight_device *bl = platform_get_drvdata(pdev);
165 backlight_device_unregister(bl);
169 static struct platform_driver da903x_backlight_driver = {
171 .name = "da903x-backlight",
172 .owner = THIS_MODULE,
174 .probe = da903x_backlight_probe,
175 .remove = da903x_backlight_remove,
178 module_platform_driver(da903x_backlight_driver);
180 MODULE_DESCRIPTION("Backlight Driver for Dialog Semiconductor DA9030/DA9034");
181 MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>");
182 MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");
183 MODULE_LICENSE("GPL");
184 MODULE_ALIAS("platform:da903x-backlight");