diff options
Diffstat (limited to 'drivers/video/backlight/adx_bl.c')
| -rw-r--r-- | drivers/video/backlight/adx_bl.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/drivers/video/backlight/adx_bl.c b/drivers/video/backlight/adx_bl.c new file mode 100644 index 000000000000..2c3bdfc620b7 --- /dev/null +++ b/drivers/video/backlight/adx_bl.c @@ -0,0 +1,178 @@ +/* + * linux/drivers/video/backlight/adx.c + * + * Copyright (C) 2009 Avionic Design GmbH + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Written by Thierry Reding <thierry.reding@avionic-design.de> + */ + +#include <linux/backlight.h> +#include <linux/fb.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> + +/* register definitions */ +#define ADX_BACKLIGHT_CONTROL 0x00 +#define ADX_BACKLIGHT_CONTROL_ENABLE (1 << 0) +#define ADX_BACKLIGHT_BRIGHTNESS 0x08 +#define ADX_BACKLIGHT_STATUS 0x10 +#define ADX_BACKLIGHT_ERROR 0x18 + +struct adxbl { + void __iomem *base; +}; + +static int adx_backlight_update_status(struct backlight_device *bldev) +{ + struct adxbl *bl = bl_get_data(bldev); + u32 value; + + value = bldev->props.brightness; + writel(value, bl->base + ADX_BACKLIGHT_BRIGHTNESS); + + value = readl(bl->base + ADX_BACKLIGHT_CONTROL); + + if (bldev->props.state & BL_CORE_FBBLANK) + value &= ~ADX_BACKLIGHT_CONTROL_ENABLE; + else + value |= ADX_BACKLIGHT_CONTROL_ENABLE; + + writel(value, bl->base + ADX_BACKLIGHT_CONTROL); + + return 0; +} + +static int adx_backlight_get_brightness(struct backlight_device *bldev) +{ + struct adxbl *bl = bl_get_data(bldev); + u32 brightness; + + brightness = readl(bl->base + ADX_BACKLIGHT_BRIGHTNESS); + return brightness & 0xff; +} + +static int adx_backlight_check_fb(struct fb_info *fb) +{ + return 1; +} + +static struct backlight_ops adx_backlight_ops = { + .options = 0, + .update_status = adx_backlight_update_status, + .get_brightness = adx_backlight_get_brightness, + .check_fb = adx_backlight_check_fb, +}; + +static int __devinit adx_backlight_probe(struct platform_device *pdev) +{ + struct backlight_device *bldev; + struct resource *res; + struct adxbl *bl; + int ret = 0; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + ret = -ENXIO; + goto out; + } + + res = devm_request_mem_region(&pdev->dev, res->start, + resource_size(res), res->name); + if (!res) { + ret = -ENXIO; + goto out; + } + + bl = devm_kzalloc(&pdev->dev, sizeof(*bl), GFP_KERNEL); + if (!bl) { + ret = -ENOMEM; + goto out; + } + + bl->base = devm_ioremap_nocache(&pdev->dev, res->start, + resource_size(res)); + if (!bl->base) { + ret = -ENXIO; + goto out; + } + + bldev = backlight_device_register(dev_name(&pdev->dev), &pdev->dev, bl, + &adx_backlight_ops); + if (!bldev) { + ret = -ENOMEM; + goto out; + } + + bldev->props.max_brightness = 0xff; + bldev->props.brightness = 0xff; + bldev->props.power = FB_BLANK_UNBLANK; + + platform_set_drvdata(pdev, bldev); + +out: + return ret; +} + +static int __devexit adx_backlight_remove(struct platform_device *pdev) +{ + struct backlight_device *bldev; + int ret = 0; + + bldev = platform_get_drvdata(pdev); + bldev->props.power = FB_BLANK_UNBLANK; + bldev->props.brightness = 0xff; + backlight_update_status(bldev); + backlight_device_unregister(bldev); + platform_set_drvdata(pdev, NULL); + + return ret; +} + +#ifdef CONFIG_PM +static int adx_backlight_suspend(struct platform_device *pdev, + pm_message_t state) +{ + return 0; +} + +static int adx_backlight_resume(struct platform_device *pdev) +{ + return 0; +} +#else +#define adx_backlight_suspend NULL +#define adx_backlight_resume NULL +#endif + +static struct platform_driver adx_backlight_driver = { + .probe = adx_backlight_probe, + .remove = __devexit_p(adx_backlight_remove), + .suspend = adx_backlight_suspend, + .resume = adx_backlight_resume, + .driver = { + .name = "adx-backlight", + .owner = THIS_MODULE, + }, +}; + +static int __init adx_backlight_init(void) +{ + return platform_driver_register(&adx_backlight_driver); +} + +static void __exit adx_backlight_exit(void) +{ + platform_driver_unregister(&adx_backlight_driver); +} + +module_init(adx_backlight_init); +module_exit(adx_backlight_exit); + +MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>"); +MODULE_DESCRIPTION("Avionic Design Xanthos Backlight Driver"); +MODULE_LICENSE("GPL v2"); |