Initial import

1 files changed, 274 insertions, 0 deletions

diff --git a/drivers/video/backlight/88pm860x_bl.c b/drivers/video/backlight/88pm860x_bl.c
new file mode 100644
index 000000000..2da586287
--- /dev/null
+++ b/drivers/video/backlight/88pm860x_bl.c
@@ -0,0 +1,274 @@
+/*
+ * Backlight driver for Marvell Semiconductor 88PM8606
+ *
+ * Copyright (C) 2009 Marvell International Ltd.
+ *	Haojian Zhuang <haojian.zhuang@marvell.com>
+ *
+ * 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.
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/fb.h>
+#include <linux/i2c.h>
+#include <linux/backlight.h>
+#include <linux/mfd/88pm860x.h>
+#include <linux/module.h>
+
+#define MAX_BRIGHTNESS		(0xFF)
+#define MIN_BRIGHTNESS		(0)
+
+#define CURRENT_BITMASK		(0x1F << 1)
+
+struct pm860x_backlight_data {
+	struct pm860x_chip *chip;
+	struct i2c_client *i2c;
+	int	current_brightness;
+	int	port;
+	int	pwm;
+	int	iset;
+	int	reg_duty_cycle;
+	int	reg_always_on;
+	int	reg_current;
+};
+
+static int backlight_power_set(struct pm860x_chip *chip, int port,
+		int on)
+{
+	int ret = -EINVAL;
+
+	switch (port) {
+	case 0:
+		ret = on ? pm8606_osc_enable(chip, WLED1_DUTY) :
+			pm8606_osc_disable(chip, WLED1_DUTY);
+		break;
+	case 1:
+		ret = on ? pm8606_osc_enable(chip, WLED2_DUTY) :
+			pm8606_osc_disable(chip, WLED2_DUTY);
+		break;
+	case 2:
+		ret = on ? pm8606_osc_enable(chip, WLED3_DUTY) :
+			pm8606_osc_disable(chip, WLED3_DUTY);
+		break;
+	}
+	return ret;
+}
+
+static int pm860x_backlight_set(struct backlight_device *bl, int brightness)
+{
+	struct pm860x_backlight_data *data = bl_get_data(bl);
+	struct pm860x_chip *chip = data->chip;
+	unsigned char value;
+	int ret;
+
+	if (brightness > MAX_BRIGHTNESS)
+		value = MAX_BRIGHTNESS;
+	else
+		value = brightness;
+
+	if (brightness)
+		backlight_power_set(chip, data->port, 1);
+
+	ret = pm860x_reg_write(data->i2c, data->reg_duty_cycle, value);
+	if (ret < 0)
+		goto out;
+
+	if ((data->current_brightness == 0) && brightness) {
+		if (data->iset) {
+			ret = pm860x_set_bits(data->i2c, data->reg_current,
+					      CURRENT_BITMASK, data->iset);
+			if (ret < 0)
+				goto out;
+		}
+		if (data->pwm) {
+			ret = pm860x_set_bits(data->i2c, PM8606_PWM,
+					      PM8606_PWM_FREQ_MASK, data->pwm);
+			if (ret < 0)
+				goto out;
+		}
+		if (brightness == MAX_BRIGHTNESS) {
+			/* set WLED_ON bit as 100% */
+			ret = pm860x_set_bits(data->i2c, data->reg_always_on,
+					      PM8606_WLED_ON, PM8606_WLED_ON);
+		}
+	} else {
+		if (brightness == MAX_BRIGHTNESS) {
+			/* set WLED_ON bit as 100% */
+			ret = pm860x_set_bits(data->i2c, data->reg_always_on,
+					      PM8606_WLED_ON, PM8606_WLED_ON);
+		} else {
+			/* clear WLED_ON bit since it's not 100% */
+			ret = pm860x_set_bits(data->i2c, data->reg_always_on,
+					      PM8606_WLED_ON, 0);
+		}
+	}
+	if (ret < 0)
+		goto out;
+
+	if (brightness == 0)
+		backlight_power_set(chip, data->port, 0);
+
+	dev_dbg(chip->dev, "set brightness %d\n", value);
+	data->current_brightness = value;
+	return 0;
+out:
+	dev_dbg(chip->dev, "set brightness %d failure with return value: %d\n",
+		value, ret);
+	return ret;
+}
+
+static int pm860x_backlight_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;
+
+	if (bl->props.state & BL_CORE_SUSPENDED)
+		brightness = 0;
+
+	return pm860x_backlight_set(bl, brightness);
+}
+
+static int pm860x_backlight_get_brightness(struct backlight_device *bl)
+{
+	struct pm860x_backlight_data *data = bl_get_data(bl);
+	struct pm860x_chip *chip = data->chip;
+	int ret;
+
+	ret = pm860x_reg_read(data->i2c, data->reg_duty_cycle);
+	if (ret < 0)
+		goto out;
+	data->current_brightness = ret;
+	dev_dbg(chip->dev, "get brightness %d\n", data->current_brightness);
+	return data->current_brightness;
+out:
+	return -EINVAL;
+}
+
+static const struct backlight_ops pm860x_backlight_ops = {
+	.options	= BL_CORE_SUSPENDRESUME,
+	.update_status	= pm860x_backlight_update_status,
+	.get_brightness	= pm860x_backlight_get_brightness,
+};
+
+#ifdef CONFIG_OF
+static int pm860x_backlight_dt_init(struct platform_device *pdev,
+				    struct pm860x_backlight_data *data,
+				    char *name)
+{
+	struct device_node *nproot, *np;
+	int iset = 0;
+
+	nproot = of_get_child_by_name(pdev->dev.parent->of_node, "backlights");
+	if (!nproot) {
+		dev_err(&pdev->dev, "failed to find backlights node\n");
+		return -ENODEV;
+	}
+	for_each_child_of_node(nproot, np) {
+		if (!of_node_cmp(np->name, name)) {
+			of_property_read_u32(np, "marvell,88pm860x-iset",
+					     &iset);
+			data->iset = PM8606_WLED_CURRENT(iset);
+			of_property_read_u32(np, "marvell,88pm860x-pwm",
+					     &data->pwm);
+			break;
+		}
+	}
+	of_node_put(nproot);
+	return 0;
+}
+#else
+#define pm860x_backlight_dt_init(x, y, z)	(-1)
+#endif
+
+static int pm860x_backlight_probe(struct platform_device *pdev)
+{
+	struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
+	struct pm860x_backlight_pdata *pdata = dev_get_platdata(&pdev->dev);
+	struct pm860x_backlight_data *data;
+	struct backlight_device *bl;
+	struct resource *res;
+	struct backlight_properties props;
+	char name[MFD_NAME_SIZE];
+	int ret = 0;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(struct pm860x_backlight_data),
+			    GFP_KERNEL);
+	if (data == NULL)
+		return -ENOMEM;
+	res = platform_get_resource_byname(pdev, IORESOURCE_REG, "duty cycle");
+	if (!res) {
+		dev_err(&pdev->dev, "No REG resource for duty cycle\n");
+		return -ENXIO;
+	}
+	data->reg_duty_cycle = res->start;
+	res = platform_get_resource_byname(pdev, IORESOURCE_REG, "always on");
+	if (!res) {
+		dev_err(&pdev->dev, "No REG resource for always on\n");
+		return -ENXIO;
+	}
+	data->reg_always_on = res->start;
+	res = platform_get_resource_byname(pdev, IORESOURCE_REG, "current");
+	if (!res) {
+		dev_err(&pdev->dev, "No REG resource for current\n");
+		return -ENXIO;
+	}
+	data->reg_current = res->start;
+
+	memset(name, 0, MFD_NAME_SIZE);
+	sprintf(name, "backlight-%d", pdev->id);
+	data->port = pdev->id;
+	data->chip = chip;
+	data->i2c = (chip->id == CHIP_PM8606) ? chip->client : chip->companion;
+	data->current_brightness = MAX_BRIGHTNESS;
+	if (pm860x_backlight_dt_init(pdev, data, name)) {
+		if (pdata) {
+			data->pwm = pdata->pwm;
+			data->iset = pdata->iset;
+		}
+	}
+
+	memset(&props, 0, sizeof(struct backlight_properties));
+	props.type = BACKLIGHT_RAW;
+	props.max_brightness = MAX_BRIGHTNESS;
+	bl = devm_backlight_device_register(&pdev->dev, name, &pdev->dev, data,
+					&pm860x_backlight_ops, &props);
+	if (IS_ERR(bl)) {
+		dev_err(&pdev->dev, "failed to register backlight\n");
+		return PTR_ERR(bl);
+	}
+	bl->props.brightness = MAX_BRIGHTNESS;
+
+	platform_set_drvdata(pdev, bl);
+
+	/* read current backlight */
+	ret = pm860x_backlight_get_brightness(bl);
+	if (ret < 0)
+		return ret;
+
+	backlight_update_status(bl);
+	return 0;
+}
+
+static struct platform_driver pm860x_backlight_driver = {
+	.driver		= {
+		.name	= "88pm860x-backlight",
+	},
+	.probe		= pm860x_backlight_probe,
+};
+
+module_platform_driver(pm860x_backlight_driver);
+
+MODULE_DESCRIPTION("Backlight Driver for Marvell Semiconductor 88PM8606");
+MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:88pm860x-backlight");