From 3b96ea9ef837c010f2187e0618d823fbdd8eeb54 Mon Sep 17 00:00:00 2001
From: Thierry Reding <thierry.reding@avionic-design.de>
Date: Fri, 14 Aug 2009 15:58:56 +0200
Subject: backlight: Add support for the Avionic Design Xanthos backlight
device.
This patch adds support for the backlight device found on Avionic Design
Xanthos-based boards.
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
---
drivers/video/backlight/adx_bl.c | 178 +++++++++++++++++++++++++++++++++++++++
1 file changed, 178 insertions(+)
create mode 100644 drivers/video/backlight/adx_bl.c
(limited to 'drivers/video/backlight/adx_bl.c')
diff --git a/drivers/video/backlight/adx_bl.c b/drivers/video/backlight/adx_bl.c
new file mode 100644
index 00000000000..2c3bdfc620b
--- /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");
--
cgit v1.2.3-70-g09d2