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>
23 #define DA9030_WLED_CONTROL 0x25
24 #define DA9030_WLED_CP_EN (1 << 6)
25 #define DA9030_WLED_TRIM(x) ((x) & 0x7)
27 #define DA9034_WLED_CONTROL1 0x3C
28 #define DA9034_WLED_CONTROL2 0x3D
29 #define DA9034_WLED_ISET(x) ((x) & 0x1f)
31 #define DA9034_WLED_BOOST_EN (1 << 5)
33 #define DA9030_MAX_BRIGHTNESS 7
34 #define DA9034_MAX_BRIGHTNESS 0x7f
36 struct da903x_backlight_data {
37 struct device *da903x_dev;
39 int current_brightness;
42 static int da903x_backlight_set(struct backlight_device *bl, int brightness)
44 struct da903x_backlight_data *data = bl_get_data(bl);
45 struct device *dev = data->da903x_dev;
51 ret = da903x_update(dev, DA9034_WLED_CONTROL1,
56 if (data->current_brightness && brightness == 0)
57 ret = da903x_clr_bits(dev,
59 DA9034_WLED_BOOST_EN);
61 if (data->current_brightness == 0 && brightness)
62 ret = da903x_set_bits(dev,
64 DA9034_WLED_BOOST_EN);
67 val = DA9030_WLED_TRIM(brightness);
68 val |= brightness ? DA9030_WLED_CP_EN : 0;
69 ret = da903x_write(dev, DA9030_WLED_CONTROL, val);
76 data->current_brightness = brightness;
80 static int da903x_backlight_update_status(struct backlight_device *bl)
82 int brightness = bl->props.brightness;
84 if (bl->props.power != FB_BLANK_UNBLANK)
87 if (bl->props.fb_blank != FB_BLANK_UNBLANK)
90 return da903x_backlight_set(bl, brightness);
93 static int da903x_backlight_get_brightness(struct backlight_device *bl)
95 struct da903x_backlight_data *data = bl_get_data(bl);
96 return data->current_brightness;
99 static const struct backlight_ops da903x_backlight_ops = {
100 .update_status = da903x_backlight_update_status,
101 .get_brightness = da903x_backlight_get_brightness,
104 static int da903x_backlight_probe(struct platform_device *pdev)
106 struct da9034_backlight_pdata *pdata = pdev->dev.platform_data;
107 struct da903x_backlight_data *data;
108 struct backlight_device *bl;
109 struct backlight_properties props;
112 data = kzalloc(sizeof(*data), GFP_KERNEL);
118 max_brightness = DA9030_MAX_BRIGHTNESS;
121 max_brightness = DA9034_MAX_BRIGHTNESS;
124 dev_err(&pdev->dev, "invalid backlight device ID(%d)\n",
131 data->da903x_dev = pdev->dev.parent;
132 data->current_brightness = 0;
134 /* adjust the WLED output current */
136 da903x_write(data->da903x_dev, DA9034_WLED_CONTROL2,
137 DA9034_WLED_ISET(pdata->output_current));
139 props.max_brightness = max_brightness;
140 bl = backlight_device_register(pdev->name, data->da903x_dev, data,
141 &da903x_backlight_ops, &props);
143 dev_err(&pdev->dev, "failed to register backlight\n");
148 bl->props.brightness = max_brightness;
150 platform_set_drvdata(pdev, bl);
151 backlight_update_status(bl);
155 static int da903x_backlight_remove(struct platform_device *pdev)
157 struct backlight_device *bl = platform_get_drvdata(pdev);
158 struct da903x_backlight_data *data = bl_get_data(bl);
160 backlight_device_unregister(bl);
166 static int da903x_backlight_suspend(struct device *dev)
168 struct platform_device *pdev = to_platform_device(dev);
169 struct backlight_device *bl = platform_get_drvdata(pdev);
170 return da903x_backlight_set(bl, 0);
173 static int da903x_backlight_resume(struct device *dev)
175 struct platform_device *pdev = to_platform_device(dev);
176 struct backlight_device *bl = platform_get_drvdata(pdev);
178 backlight_update_status(bl);
182 static const struct dev_pm_ops da903x_backlight_pm_ops = {
183 .suspend = da903x_backlight_suspend,
184 .resume = da903x_backlight_resume,
188 static struct platform_driver da903x_backlight_driver = {
190 .name = "da903x-backlight",
191 .owner = THIS_MODULE,
193 .pm = &da903x_backlight_pm_ops,
196 .probe = da903x_backlight_probe,
197 .remove = da903x_backlight_remove,
200 static int __init da903x_backlight_init(void)
202 return platform_driver_register(&da903x_backlight_driver);
204 module_init(da903x_backlight_init);
206 static void __exit da903x_backlight_exit(void)
208 platform_driver_unregister(&da903x_backlight_driver);
210 module_exit(da903x_backlight_exit);
212 MODULE_DESCRIPTION("Backlight Driver for Dialog Semiconductor DA9030/DA9034");
213 MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>"
214 "Mike Rapoport <mike@compulab.co.il>");
215 MODULE_LICENSE("GPL");
216 MODULE_ALIAS("platform:da903x-backlight");