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/adp5520_bl.c b/drivers/video/backlight/adp5520_bl.c
new file mode 100644
index 0000000..35373e2
--- /dev/null
+++ b/drivers/video/backlight/adp5520_bl.c
@@ -0,0 +1,397 @@
+/*
+ * Backlight driver for Analog Devices ADP5520/ADP5501 MFD PMICs
+ *
+ * Copyright 2009 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/fb.h>
+#include <linux/backlight.h>
+#include <linux/mfd/adp5520.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+struct adp5520_bl {
+	struct device *master;
+	struct adp5520_backlight_platform_data *pdata;
+	struct mutex lock;
+	unsigned long cached_daylight_max;
+	int id;
+	int current_brightness;
+};
+
+static int adp5520_bl_set(struct backlight_device *bl, int brightness)
+{
+	struct adp5520_bl *data = bl_get_data(bl);
+	struct device *master = data->master;
+	int ret = 0;
+
+	if (data->pdata->en_ambl_sens) {
+		if ((brightness > 0) && (brightness < ADP5020_MAX_BRIGHTNESS)) {
+			/* Disable Ambient Light auto adjust */
+			ret |= adp5520_clr_bits(master, ADP5520_BL_CONTROL,
+					ADP5520_BL_AUTO_ADJ);
+			ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
+					brightness);
+		} else {
+			/*
+			 * MAX_BRIGHTNESS -> Enable Ambient Light auto adjust
+			 * restore daylight l3 sysfs brightness
+			 */
+			ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
+					 data->cached_daylight_max);
+			ret |= adp5520_set_bits(master, ADP5520_BL_CONTROL,
+					 ADP5520_BL_AUTO_ADJ);
+		}
+	} else {
+		ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX, brightness);
+	}
+
+	if (data->current_brightness && brightness == 0)
+		ret |= adp5520_set_bits(master,
+				ADP5520_MODE_STATUS, ADP5520_DIM_EN);
+	else if (data->current_brightness == 0 && brightness)
+		ret |= adp5520_clr_bits(master,
+				ADP5520_MODE_STATUS, ADP5520_DIM_EN);
+
+	if (!ret)
+		data->current_brightness = brightness;
+
+	return ret;
+}
+
+static int adp5520_bl_update_status(struct backlight_device *bl)
+{
+	int brightness = bl->props.brightness;
+
+	if (bl->props.power != FB_BLANK_UNBLANK)
+		brightness = 0;
+
+	if (bl->props.fb_blank != FB_BLANK_UNBLANK)
+		brightness = 0;
+
+	return adp5520_bl_set(bl, brightness);
+}
+
+static int adp5520_bl_get_brightness(struct backlight_device *bl)
+{
+	struct adp5520_bl *data = bl_get_data(bl);
+	int error;
+	uint8_t reg_val;
+
+	error = adp5520_read(data->master, ADP5520_BL_VALUE, &reg_val);
+
+	return error ? data->current_brightness : reg_val;
+}
+
+static const struct backlight_ops adp5520_bl_ops = {
+	.update_status	= adp5520_bl_update_status,
+	.get_brightness	= adp5520_bl_get_brightness,
+};
+
+static int adp5520_bl_setup(struct backlight_device *bl)
+{
+	struct adp5520_bl *data = bl_get_data(bl);
+	struct device *master = data->master;
+	struct adp5520_backlight_platform_data *pdata = data->pdata;
+	int ret = 0;
+
+	ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
+				pdata->l1_daylight_max);
+	ret |= adp5520_write(master, ADP5520_DAYLIGHT_DIM,
+				pdata->l1_daylight_dim);
+
+	if (pdata->en_ambl_sens) {
+		data->cached_daylight_max = pdata->l1_daylight_max;
+		ret |= adp5520_write(master, ADP5520_OFFICE_MAX,
+				pdata->l2_office_max);
+		ret |= adp5520_write(master, ADP5520_OFFICE_DIM,
+				pdata->l2_office_dim);
+		ret |= adp5520_write(master, ADP5520_DARK_MAX,
+				pdata->l3_dark_max);
+		ret |= adp5520_write(master, ADP5520_DARK_DIM,
+				pdata->l3_dark_dim);
+		ret |= adp5520_write(master, ADP5520_L2_TRIP,
+				pdata->l2_trip);
+		ret |= adp5520_write(master, ADP5520_L2_HYS,
+				pdata->l2_hyst);
+		ret |= adp5520_write(master, ADP5520_L3_TRIP,
+				 pdata->l3_trip);
+		ret |= adp5520_write(master, ADP5520_L3_HYS,
+				pdata->l3_hyst);
+		ret |= adp5520_write(master, ADP5520_ALS_CMPR_CFG,
+				ALS_CMPR_CFG_VAL(pdata->abml_filt,
+				ADP5520_L3_EN));
+	}
+
+	ret |= adp5520_write(master, ADP5520_BL_CONTROL,
+			BL_CTRL_VAL(pdata->fade_led_law,
+					pdata->en_ambl_sens));
+
+	ret |= adp5520_write(master, ADP5520_BL_FADE, FADE_VAL(pdata->fade_in,
+			pdata->fade_out));
+
+	ret |= adp5520_set_bits(master, ADP5520_MODE_STATUS,
+			ADP5520_BL_EN | ADP5520_DIM_EN);
+
+	return ret;
+}
+
+static ssize_t adp5520_show(struct device *dev, char *buf, int reg)
+{
+	struct adp5520_bl *data = dev_get_drvdata(dev);
+	int ret;
+	uint8_t reg_val;
+
+	mutex_lock(&data->lock);
+	ret = adp5520_read(data->master, reg, &reg_val);
+	mutex_unlock(&data->lock);
+
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%u\n", reg_val);
+}
+
+static ssize_t adp5520_store(struct device *dev, const char *buf,
+			 size_t count, int reg)
+{
+	struct adp5520_bl *data = dev_get_drvdata(dev);
+	unsigned long val;
+	int ret;
+
+	ret = kstrtoul(buf, 10, &val);
+	if (ret)
+		return ret;
+
+	mutex_lock(&data->lock);
+	adp5520_write(data->master, reg, val);
+	mutex_unlock(&data->lock);
+
+	return count;
+}
+
+static ssize_t adp5520_bl_dark_max_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	return adp5520_show(dev, buf, ADP5520_DARK_MAX);
+}
+
+static ssize_t adp5520_bl_dark_max_store(struct device *dev,
+			struct device_attribute *attr,
+			const char *buf, size_t count)
+{
+	return adp5520_store(dev, buf, count, ADP5520_DARK_MAX);
+}
+static DEVICE_ATTR(dark_max, 0664, adp5520_bl_dark_max_show,
+			adp5520_bl_dark_max_store);
+
+static ssize_t adp5520_bl_office_max_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	return adp5520_show(dev, buf, ADP5520_OFFICE_MAX);
+}
+
+static ssize_t adp5520_bl_office_max_store(struct device *dev,
+			struct device_attribute *attr,
+			const char *buf, size_t count)
+{
+	return adp5520_store(dev, buf, count, ADP5520_OFFICE_MAX);
+}
+static DEVICE_ATTR(office_max, 0664, adp5520_bl_office_max_show,
+			adp5520_bl_office_max_store);
+
+static ssize_t adp5520_bl_daylight_max_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	return adp5520_show(dev, buf, ADP5520_DAYLIGHT_MAX);
+}
+
+static ssize_t adp5520_bl_daylight_max_store(struct device *dev,
+			struct device_attribute *attr,
+			const char *buf, size_t count)
+{
+	struct adp5520_bl *data = dev_get_drvdata(dev);
+	int ret;
+
+	ret = kstrtoul(buf, 10, &data->cached_daylight_max);
+	if (ret < 0)
+		return ret;
+
+	return adp5520_store(dev, buf, count, ADP5520_DAYLIGHT_MAX);
+}
+static DEVICE_ATTR(daylight_max, 0664, adp5520_bl_daylight_max_show,
+			adp5520_bl_daylight_max_store);
+
+static ssize_t adp5520_bl_dark_dim_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	return adp5520_show(dev, buf, ADP5520_DARK_DIM);
+}
+
+static ssize_t adp5520_bl_dark_dim_store(struct device *dev,
+			struct device_attribute *attr,
+			const char *buf, size_t count)
+{
+	return adp5520_store(dev, buf, count, ADP5520_DARK_DIM);
+}
+static DEVICE_ATTR(dark_dim, 0664, adp5520_bl_dark_dim_show,
+			adp5520_bl_dark_dim_store);
+
+static ssize_t adp5520_bl_office_dim_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	return adp5520_show(dev, buf, ADP5520_OFFICE_DIM);
+}
+
+static ssize_t adp5520_bl_office_dim_store(struct device *dev,
+			struct device_attribute *attr,
+			const char *buf, size_t count)
+{
+	return adp5520_store(dev, buf, count, ADP5520_OFFICE_DIM);
+}
+static DEVICE_ATTR(office_dim, 0664, adp5520_bl_office_dim_show,
+			adp5520_bl_office_dim_store);
+
+static ssize_t adp5520_bl_daylight_dim_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	return adp5520_show(dev, buf, ADP5520_DAYLIGHT_DIM);
+}
+
+static ssize_t adp5520_bl_daylight_dim_store(struct device *dev,
+			struct device_attribute *attr,
+			const char *buf, size_t count)
+{
+	return adp5520_store(dev, buf, count, ADP5520_DAYLIGHT_DIM);
+}
+static DEVICE_ATTR(daylight_dim, 0664, adp5520_bl_daylight_dim_show,
+			adp5520_bl_daylight_dim_store);
+
+static struct attribute *adp5520_bl_attributes[] = {
+	&dev_attr_dark_max.attr,
+	&dev_attr_dark_dim.attr,
+	&dev_attr_office_max.attr,
+	&dev_attr_office_dim.attr,
+	&dev_attr_daylight_max.attr,
+	&dev_attr_daylight_dim.attr,
+	NULL
+};
+
+static const struct attribute_group adp5520_bl_attr_group = {
+	.attrs = adp5520_bl_attributes,
+};
+
+static int adp5520_bl_probe(struct platform_device *pdev)
+{
+	struct backlight_properties props;
+	struct backlight_device *bl;
+	struct adp5520_bl *data;
+	int ret = 0;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (data == NULL)
+		return -ENOMEM;
+
+	data->master = pdev->dev.parent;
+	data->pdata = dev_get_platdata(&pdev->dev);
+
+	if (data->pdata  == NULL) {
+		dev_err(&pdev->dev, "missing platform data\n");
+		return -ENODEV;
+	}
+
+	data->id = pdev->id;
+	data->current_brightness = 0;
+
+	mutex_init(&data->lock);
+
+	memset(&props, 0, sizeof(struct backlight_properties));
+	props.type = BACKLIGHT_RAW;
+	props.max_brightness = ADP5020_MAX_BRIGHTNESS;
+	bl = devm_backlight_device_register(&pdev->dev, pdev->name,
+					data->master, data, &adp5520_bl_ops,
+					&props);
+	if (IS_ERR(bl)) {
+		dev_err(&pdev->dev, "failed to register backlight\n");
+		return PTR_ERR(bl);
+	}
+
+	bl->props.brightness = ADP5020_MAX_BRIGHTNESS;
+	if (data->pdata->en_ambl_sens)
+		ret = sysfs_create_group(&bl->dev.kobj,
+			&adp5520_bl_attr_group);
+
+	if (ret) {
+		dev_err(&pdev->dev, "failed to register sysfs\n");
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, bl);
+	ret = adp5520_bl_setup(bl);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to setup\n");
+		if (data->pdata->en_ambl_sens)
+			sysfs_remove_group(&bl->dev.kobj,
+					&adp5520_bl_attr_group);
+		return ret;
+	}
+
+	backlight_update_status(bl);
+
+	return 0;
+}
+
+static int adp5520_bl_remove(struct platform_device *pdev)
+{
+	struct backlight_device *bl = platform_get_drvdata(pdev);
+	struct adp5520_bl *data = bl_get_data(bl);
+
+	adp5520_clr_bits(data->master, ADP5520_MODE_STATUS, ADP5520_BL_EN);
+
+	if (data->pdata->en_ambl_sens)
+		sysfs_remove_group(&bl->dev.kobj,
+				&adp5520_bl_attr_group);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int adp5520_bl_suspend(struct device *dev)
+{
+	struct backlight_device *bl = dev_get_drvdata(dev);
+
+	return adp5520_bl_set(bl, 0);
+}
+
+static int adp5520_bl_resume(struct device *dev)
+{
+	struct backlight_device *bl = dev_get_drvdata(dev);
+
+	backlight_update_status(bl);
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(adp5520_bl_pm_ops, adp5520_bl_suspend,
+			adp5520_bl_resume);
+
+static struct platform_driver adp5520_bl_driver = {
+	.driver		= {
+		.name	= "adp5520-backlight",
+		.pm	= &adp5520_bl_pm_ops,
+	},
+	.probe		= adp5520_bl_probe,
+	.remove		= adp5520_bl_remove,
+};
+
+module_platform_driver(adp5520_bl_driver);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("ADP5520(01) Backlight Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:adp5520-backlight");