2 * linux/drivers/video/backlight/adx.c
4 * Copyright (C) 2009 Avionic Design GmbH
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
10 * Written by Thierry Reding <thierry.reding@avionic-design.de>
13 #include <linux/backlight.h>
15 #include <linux/gfp.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
20 /* register definitions */
21 #define ADX_BACKLIGHT_CONTROL 0x00
22 #define ADX_BACKLIGHT_CONTROL_ENABLE (1 << 0)
23 #define ADX_BACKLIGHT_BRIGHTNESS 0x08
24 #define ADX_BACKLIGHT_STATUS 0x10
25 #define ADX_BACKLIGHT_ERROR 0x18
31 static int adx_backlight_update_status(struct backlight_device *bldev)
33 struct adxbl *bl = bl_get_data(bldev);
36 value = bldev->props.brightness;
37 writel(value, bl->base + ADX_BACKLIGHT_BRIGHTNESS);
39 value = readl(bl->base + ADX_BACKLIGHT_CONTROL);
41 if (bldev->props.state & BL_CORE_FBBLANK)
42 value &= ~ADX_BACKLIGHT_CONTROL_ENABLE;
44 value |= ADX_BACKLIGHT_CONTROL_ENABLE;
46 writel(value, bl->base + ADX_BACKLIGHT_CONTROL);
51 static int adx_backlight_get_brightness(struct backlight_device *bldev)
53 struct adxbl *bl = bl_get_data(bldev);
56 brightness = readl(bl->base + ADX_BACKLIGHT_BRIGHTNESS);
57 return brightness & 0xff;
60 static int adx_backlight_check_fb(struct backlight_device *bldev, struct fb_info *fb)
65 static const struct backlight_ops adx_backlight_ops = {
67 .update_status = adx_backlight_update_status,
68 .get_brightness = adx_backlight_get_brightness,
69 .check_fb = adx_backlight_check_fb,
72 static int __devinit adx_backlight_probe(struct platform_device *pdev)
74 struct backlight_properties props;
75 struct backlight_device *bldev;
80 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
86 res = devm_request_mem_region(&pdev->dev, res->start,
87 resource_size(res), res->name);
93 bl = devm_kzalloc(&pdev->dev, sizeof(*bl), GFP_KERNEL);
99 bl->base = devm_ioremap_nocache(&pdev->dev, res->start,
106 memset(&props, 0, sizeof(struct backlight_properties));
107 props.type = BACKLIGHT_RAW;
108 props.max_brightness = 0xff;
109 bldev = backlight_device_register(dev_name(&pdev->dev), &pdev->dev,
110 bl, &adx_backlight_ops, &props);
112 ret = PTR_ERR(bldev);
116 bldev->props.brightness = 0xff;
117 bldev->props.power = FB_BLANK_UNBLANK;
119 platform_set_drvdata(pdev, bldev);
125 static int __devexit adx_backlight_remove(struct platform_device *pdev)
127 struct backlight_device *bldev;
130 bldev = platform_get_drvdata(pdev);
131 bldev->props.power = FB_BLANK_UNBLANK;
132 bldev->props.brightness = 0xff;
133 backlight_update_status(bldev);
134 backlight_device_unregister(bldev);
135 platform_set_drvdata(pdev, NULL);
141 static int adx_backlight_suspend(struct platform_device *pdev,
147 static int adx_backlight_resume(struct platform_device *pdev)
152 #define adx_backlight_suspend NULL
153 #define adx_backlight_resume NULL
156 static struct platform_driver adx_backlight_driver = {
157 .probe = adx_backlight_probe,
158 .remove = __devexit_p(adx_backlight_remove),
159 .suspend = adx_backlight_suspend,
160 .resume = adx_backlight_resume,
162 .name = "adx-backlight",
163 .owner = THIS_MODULE,
167 static int __init adx_backlight_init(void)
169 return platform_driver_register(&adx_backlight_driver);
172 static void __exit adx_backlight_exit(void)
174 platform_driver_unregister(&adx_backlight_driver);
177 module_init(adx_backlight_init);
178 module_exit(adx_backlight_exit);
180 MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
181 MODULE_DESCRIPTION("Avionic Design Xanthos Backlight Driver");
182 MODULE_LICENSE("GPL v2");