File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/video/backlight/hp680_bl.c b/drivers/video/backlight/hp680_bl.c
new file mode 100644
index 0000000..8ea42b8
--- /dev/null
+++ b/drivers/video/backlight/hp680_bl.c
@@ -0,0 +1,175 @@
+/*
+ *  Backlight Driver for HP Jornada 680
+ *
+ *  Copyright (c) 2005 Andriy Skulysh
+ *
+ *  Based on Sharp's Corgi Backlight Driver
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/fb.h>
+#include <linux/backlight.h>
+
+#include <cpu/dac.h>
+#include <mach/hp6xx.h>
+#include <asm/hd64461.h>
+
+#define HP680_MAX_INTENSITY 255
+#define HP680_DEFAULT_INTENSITY 10
+
+static int hp680bl_suspended;
+static int current_intensity;
+static DEFINE_SPINLOCK(bl_lock);
+
+static void hp680bl_send_intensity(struct backlight_device *bd)
+{
+	unsigned long flags;
+	u16 v;
+	int intensity = bd->props.brightness;
+
+	if (bd->props.power != FB_BLANK_UNBLANK)
+		intensity = 0;
+	if (bd->props.fb_blank != FB_BLANK_UNBLANK)
+		intensity = 0;
+	if (hp680bl_suspended)
+		intensity = 0;
+
+	spin_lock_irqsave(&bl_lock, flags);
+	if (intensity && current_intensity == 0) {
+		sh_dac_enable(DAC_LCD_BRIGHTNESS);
+		v = inw(HD64461_GPBDR);
+		v &= ~HD64461_GPBDR_LCDOFF;
+		outw(v, HD64461_GPBDR);
+		sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);
+	} else if (intensity == 0 && current_intensity != 0) {
+		sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);
+		sh_dac_disable(DAC_LCD_BRIGHTNESS);
+		v = inw(HD64461_GPBDR);
+		v |= HD64461_GPBDR_LCDOFF;
+		outw(v, HD64461_GPBDR);
+	} else if (intensity) {
+		sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);
+	}
+	spin_unlock_irqrestore(&bl_lock, flags);
+
+	current_intensity = intensity;
+}
+
+
+#ifdef CONFIG_PM_SLEEP
+static int hp680bl_suspend(struct device *dev)
+{
+	struct backlight_device *bd = dev_get_drvdata(dev);
+
+	hp680bl_suspended = 1;
+	hp680bl_send_intensity(bd);
+	return 0;
+}
+
+static int hp680bl_resume(struct device *dev)
+{
+	struct backlight_device *bd = dev_get_drvdata(dev);
+
+	hp680bl_suspended = 0;
+	hp680bl_send_intensity(bd);
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(hp680bl_pm_ops, hp680bl_suspend, hp680bl_resume);
+
+static int hp680bl_set_intensity(struct backlight_device *bd)
+{
+	hp680bl_send_intensity(bd);
+	return 0;
+}
+
+static int hp680bl_get_intensity(struct backlight_device *bd)
+{
+	return current_intensity;
+}
+
+static const struct backlight_ops hp680bl_ops = {
+	.get_brightness = hp680bl_get_intensity,
+	.update_status  = hp680bl_set_intensity,
+};
+
+static int hp680bl_probe(struct platform_device *pdev)
+{
+	struct backlight_properties props;
+	struct backlight_device *bd;
+
+	memset(&props, 0, sizeof(struct backlight_properties));
+	props.type = BACKLIGHT_RAW;
+	props.max_brightness = HP680_MAX_INTENSITY;
+	bd = devm_backlight_device_register(&pdev->dev, "hp680-bl", &pdev->dev,
+					NULL, &hp680bl_ops, &props);
+	if (IS_ERR(bd))
+		return PTR_ERR(bd);
+
+	platform_set_drvdata(pdev, bd);
+
+	bd->props.brightness = HP680_DEFAULT_INTENSITY;
+	hp680bl_send_intensity(bd);
+
+	return 0;
+}
+
+static int hp680bl_remove(struct platform_device *pdev)
+{
+	struct backlight_device *bd = platform_get_drvdata(pdev);
+
+	bd->props.brightness = 0;
+	bd->props.power = 0;
+	hp680bl_send_intensity(bd);
+
+	return 0;
+}
+
+static struct platform_driver hp680bl_driver = {
+	.probe		= hp680bl_probe,
+	.remove		= hp680bl_remove,
+	.driver		= {
+		.name	= "hp680-bl",
+		.pm	= &hp680bl_pm_ops,
+	},
+};
+
+static struct platform_device *hp680bl_device;
+
+static int __init hp680bl_init(void)
+{
+	int ret;
+
+	ret = platform_driver_register(&hp680bl_driver);
+	if (ret)
+		return ret;
+	hp680bl_device = platform_device_register_simple("hp680-bl", -1,
+							NULL, 0);
+	if (IS_ERR(hp680bl_device)) {
+		platform_driver_unregister(&hp680bl_driver);
+		return PTR_ERR(hp680bl_device);
+	}
+	return 0;
+}
+
+static void __exit hp680bl_exit(void)
+{
+	platform_device_unregister(hp680bl_device);
+	platform_driver_unregister(&hp680bl_driver);
+}
+
+module_init(hp680bl_init);
+module_exit(hp680bl_exit);
+
+MODULE_AUTHOR("Andriy Skulysh <askulysh@gmail.com>");
+MODULE_DESCRIPTION("HP Jornada 680 Backlight Driver");
+MODULE_LICENSE("GPL");