drivers/video/backlight/88pm860x_bl.c - kernel/skids - Git at Google

 /*
  * 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/platform_device.h>
 #include <linux/fb.h>
 #include <linux/i2c.h>
 #include <linux/backlight.h>
 #include <linux/mfd/88pm860x.h>
 #include <linux/slab.h>

 #define MAX_BRIGHTNESS		(0xFF)
 #define MIN_BRIGHTNESS		(0)

 #define CURRENT_MASK		(0x1F << 1)

 struct pm860x_backlight_data {
 	struct pm860x_chip *chip;
 	struct i2c_client *i2c;
 	int	current_brightness;
 	int	port;
 	int	pwm;
 	int	iset;
 };

 static inline int wled_a(int port)
 {
 	int ret;

 	ret = ((port - PM8606_BACKLIGHT1) << 1) + 2;
 	return ret;
 }

 static inline int wled_b(int port)
 {
 	int ret;

 	ret = ((port - PM8606_BACKLIGHT1) << 1) + 3;
 	return ret;
 }

 /* WLED2 & WLED3 share the same IDC */
 static inline int wled_idc(int port)
 {
 	int ret;

 	switch (port) {
 	case PM8606_BACKLIGHT1:
 	case PM8606_BACKLIGHT2:
 		ret = ((port - PM8606_BACKLIGHT1) << 1) + 3;
 		break;
 	case PM8606_BACKLIGHT3:
 	default:
 		ret = ((port - PM8606_BACKLIGHT2) << 1) + 3;
 		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;

 	ret = pm860x_reg_write(data->i2c, wled_a(data->port), value);
 	if (ret < 0)
 		goto out;

 	if ((data->current_brightness == 0) && brightness) {
 		if (data->iset) {
 			ret = pm860x_set_bits(data->i2c, wled_idc(data->port),
 					      CURRENT_MASK, 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, wled_b(data->port),
 					      PM8606_WLED_ON, PM8606_WLED_ON);
 		}
 	} else {
 		if (brightness == MAX_BRIGHTNESS) {
 			/* set WLED_ON bit as 100% */
 			ret = pm860x_set_bits(data->i2c, wled_b(data->port),
 					      PM8606_WLED_ON, PM8606_WLED_ON);
 		} else {
 			/* clear WLED_ON bit since it's not 100% */
 			ret = pm860x_set_bits(data->i2c, wled_b(data->port),
 					      PM8606_WLED_ON, 0);
 		}
 	}
 	if (ret < 0)
 		goto out;

 	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, wled_a(data->port));
 	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 struct backlight_ops pm860x_backlight_ops = {
 	.options	= BL_CORE_SUSPENDRESUME,
 	.update_status	= pm860x_backlight_update_status,
 	.get_brightness	= pm860x_backlight_get_brightness,
 };

 static int __check_device(struct pm860x_backlight_pdata *pdata, char *name)
 {
 	struct pm860x_backlight_pdata *p = pdata;
 	int ret = -EINVAL;

 	while (p && p->id) {
 		if ((p->id != PM8606_ID_BACKLIGHT) || (p->flags < 0))
 			break;

 		if (!strncmp(name, pm860x_backlight_name[p->flags],
 			MFD_NAME_SIZE)) {
 			ret = (int)p->flags;
 			break;
 		}
 		p++;
 	}
 	return ret;
 }

 static int pm860x_backlight_probe(struct platform_device *pdev)
 {
 	struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
 	struct pm860x_platform_data *pm860x_pdata;
 	struct pm860x_backlight_pdata *pdata = NULL;
 	struct pm860x_backlight_data *data;
 	struct backlight_device *bl;
 	struct resource *res;
 	struct backlight_properties props;
 	unsigned char value;
 	char name[MFD_NAME_SIZE];
 	int ret;

 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
 	if (res == NULL) {
 		dev_err(&pdev->dev, "No I/O resource!\n");
 		return -EINVAL;
 	}

 	if (pdev->dev.parent->platform_data) {
 		pm860x_pdata = pdev->dev.parent->platform_data;
 		pdata = pm860x_pdata->backlight;
 	}
 	if (pdata == NULL) {
 		dev_err(&pdev->dev, "platform data isn't assigned to "
 			"backlight\n");
 		return -EINVAL;
 	}

 	data = kzalloc(sizeof(struct pm860x_backlight_data), GFP_KERNEL);
 	if (data == NULL)
 		return -ENOMEM;
 	strncpy(name, res->name, MFD_NAME_SIZE);
 	data->chip = chip;
 	data->i2c = (chip->id == CHIP_PM8606) ? chip->client	\
 			: chip->companion;
 	data->current_brightness = MAX_BRIGHTNESS;
 	data->pwm = pdata->pwm;
 	data->iset = pdata->iset;
 	data->port = __check_device(pdata, name);
 	if (data->port < 0) {
 		dev_err(&pdev->dev, "wrong platform data is assigned");
 		kfree(data);
 		return -EINVAL;
 	}

 	memset(&props, 0, sizeof(struct backlight_properties));
 	props.max_brightness = MAX_BRIGHTNESS;
 	bl = backlight_device_register(name, &pdev->dev, data,
 					&pm860x_backlight_ops, &props);
 	if (IS_ERR(bl)) {
 		dev_err(&pdev->dev, "failed to register backlight\n");
 		kfree(data);
 		return PTR_ERR(bl);
 	}
 	bl->props.brightness = MAX_BRIGHTNESS;

 	platform_set_drvdata(pdev, bl);

 	/* Enable reference VSYS */
 	ret = pm860x_reg_read(data->i2c, PM8606_VSYS);
 	if (ret < 0)
 		goto out;
 	if ((ret & PM8606_VSYS_EN) == 0) {
 		value = ret | PM8606_VSYS_EN;
 		ret = pm860x_reg_write(data->i2c, PM8606_VSYS, value);
 		if (ret < 0)
 			goto out;
 	}
 	/* Enable reference OSC */
 	ret = pm860x_reg_read(data->i2c, PM8606_MISC);
 	if (ret < 0)
 		goto out;
 	if ((ret & PM8606_MISC_OSC_EN) == 0) {
 		value = ret | PM8606_MISC_OSC_EN;
 		ret = pm860x_reg_write(data->i2c, PM8606_MISC, value);
 		if (ret < 0)
 			goto out;
 	}
 	/* read current backlight */
 	ret = pm860x_backlight_get_brightness(bl);
 	if (ret < 0)
 		goto out;

 	backlight_update_status(bl);
 	return 0;
 out:
 	backlight_device_unregister(bl);
 	kfree(data);
 	return ret;
 }

 static int pm860x_backlight_remove(struct platform_device *pdev)
 {
 	struct backlight_device *bl = platform_get_drvdata(pdev);
 	struct pm860x_backlight_data *data = bl_get_data(bl);

 	backlight_device_unregister(bl);
 	kfree(data);
 	return 0;
 }

 static struct platform_driver pm860x_backlight_driver = {
 	.driver		= {
 		.name	= "88pm860x-backlight",
 		.owner	= THIS_MODULE,
 	},
 	.probe		= pm860x_backlight_probe,
 	.remove		= pm860x_backlight_remove,
 };

 static int __init pm860x_backlight_init(void)
 {
 	return platform_driver_register(&pm860x_backlight_driver);
 }
 module_init(pm860x_backlight_init);

 static void __exit pm860x_backlight_exit(void)
 {
 	platform_driver_unregister(&pm860x_backlight_driver);
 }
 module_exit(pm860x_backlight_exit);

 MODULE_DESCRIPTION("Backlight Driver for Marvell Semiconductor 88PM8606");
 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:88pm860x-backlight");
	/*
	* 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/platform_device.h>
	#include <linux/fb.h>
	#include <linux/i2c.h>
	#include <linux/backlight.h>
	#include <linux/mfd/88pm860x.h>
	#include <linux/slab.h>

	#define MAX_BRIGHTNESS (0xFF)
	#define MIN_BRIGHTNESS (0)

	#define CURRENT_MASK (0x1F << 1)

	struct pm860x_backlight_data {
	struct pm860x_chip *chip;
	struct i2c_client *i2c;
	int current_brightness;
	int port;
	int pwm;
	int iset;
	};

	static inline int wled_a(int port)
	{
	int ret;

	ret = ((port - PM8606_BACKLIGHT1) << 1) + 2;
	return ret;
	}

	static inline int wled_b(int port)
	{
	int ret;

	ret = ((port - PM8606_BACKLIGHT1) << 1) + 3;
	return ret;
	}

	/* WLED2 & WLED3 share the same IDC */
	static inline int wled_idc(int port)
	{
	int ret;

	switch (port) {
	case PM8606_BACKLIGHT1:
	case PM8606_BACKLIGHT2:
	ret = ((port - PM8606_BACKLIGHT1) << 1) + 3;
	break;
	case PM8606_BACKLIGHT3:
	default:
	ret = ((port - PM8606_BACKLIGHT2) << 1) + 3;
	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;

	ret = pm860x_reg_write(data->i2c, wled_a(data->port), value);
	if (ret < 0)
	goto out;

	if ((data->current_brightness == 0) && brightness) {
	if (data->iset) {
	ret = pm860x_set_bits(data->i2c, wled_idc(data->port),
	CURRENT_MASK, 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, wled_b(data->port),
	PM8606_WLED_ON, PM8606_WLED_ON);
	}
	} else {
	if (brightness == MAX_BRIGHTNESS) {
	/* set WLED_ON bit as 100% */
	ret = pm860x_set_bits(data->i2c, wled_b(data->port),
	PM8606_WLED_ON, PM8606_WLED_ON);
	} else {
	/* clear WLED_ON bit since it's not 100% */
	ret = pm860x_set_bits(data->i2c, wled_b(data->port),
	PM8606_WLED_ON, 0);
	}
	}
	if (ret < 0)
	goto out;

	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, wled_a(data->port));
	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 struct backlight_ops pm860x_backlight_ops = {
	.options = BL_CORE_SUSPENDRESUME,
	.update_status = pm860x_backlight_update_status,
	.get_brightness = pm860x_backlight_get_brightness,
	};

	static int __check_device(struct pm860x_backlight_pdata pdata, char name)
	{
	struct pm860x_backlight_pdata *p = pdata;
	int ret = -EINVAL;

	while (p && p->id) {
	if ((p->id != PM8606_ID_BACKLIGHT) \|\| (p->flags < 0))
	break;

	if (!strncmp(name, pm860x_backlight_name[p->flags],
	MFD_NAME_SIZE)) {
	ret = (int)p->flags;
	break;
	}
	p++;
	}
	return ret;
	}

	static int pm860x_backlight_probe(struct platform_device *pdev)
	{
	struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
	struct pm860x_platform_data *pm860x_pdata;
	struct pm860x_backlight_pdata *pdata = NULL;
	struct pm860x_backlight_data *data;
	struct backlight_device *bl;
	struct resource *res;
	struct backlight_properties props;
	unsigned char value;
	char name[MFD_NAME_SIZE];
	int ret;

	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
	if (res == NULL) {
	dev_err(&pdev->dev, "No I/O resource!\n");
	return -EINVAL;
	}

	if (pdev->dev.parent->platform_data) {
	pm860x_pdata = pdev->dev.parent->platform_data;
	pdata = pm860x_pdata->backlight;
	}
	if (pdata == NULL) {
	dev_err(&pdev->dev, "platform data isn't assigned to "
	"backlight\n");
	return -EINVAL;
	}

	data = kzalloc(sizeof(struct pm860x_backlight_data), GFP_KERNEL);
	if (data == NULL)
	return -ENOMEM;
	strncpy(name, res->name, MFD_NAME_SIZE);
	data->chip = chip;
	data->i2c = (chip->id == CHIP_PM8606) ? chip->client \
	: chip->companion;
	data->current_brightness = MAX_BRIGHTNESS;
	data->pwm = pdata->pwm;
	data->iset = pdata->iset;
	data->port = __check_device(pdata, name);
	if (data->port < 0) {
	dev_err(&pdev->dev, "wrong platform data is assigned");
	kfree(data);
	return -EINVAL;
	}

	memset(&props, 0, sizeof(struct backlight_properties));
	props.max_brightness = MAX_BRIGHTNESS;
	bl = backlight_device_register(name, &pdev->dev, data,
	&pm860x_backlight_ops, &props);
	if (IS_ERR(bl)) {
	dev_err(&pdev->dev, "failed to register backlight\n");
	kfree(data);
	return PTR_ERR(bl);
	}
	bl->props.brightness = MAX_BRIGHTNESS;

	platform_set_drvdata(pdev, bl);

	/* Enable reference VSYS */
	ret = pm860x_reg_read(data->i2c, PM8606_VSYS);
	if (ret < 0)
	goto out;
	if ((ret & PM8606_VSYS_EN) == 0) {
	value = ret \| PM8606_VSYS_EN;
	ret = pm860x_reg_write(data->i2c, PM8606_VSYS, value);
	if (ret < 0)
	goto out;
	}
	/* Enable reference OSC */
	ret = pm860x_reg_read(data->i2c, PM8606_MISC);
	if (ret < 0)
	goto out;
	if ((ret & PM8606_MISC_OSC_EN) == 0) {
	value = ret \| PM8606_MISC_OSC_EN;
	ret = pm860x_reg_write(data->i2c, PM8606_MISC, value);
	if (ret < 0)
	goto out;
	}
	/* read current backlight */
	ret = pm860x_backlight_get_brightness(bl);
	if (ret < 0)
	goto out;

	backlight_update_status(bl);
	return 0;
	out:
	backlight_device_unregister(bl);
	kfree(data);
	return ret;
	}

	static int pm860x_backlight_remove(struct platform_device *pdev)
	{
	struct backlight_device *bl = platform_get_drvdata(pdev);
	struct pm860x_backlight_data *data = bl_get_data(bl);

	backlight_device_unregister(bl);
	kfree(data);
	return 0;
	}

	static struct platform_driver pm860x_backlight_driver = {
	.driver = {
	.name = "88pm860x-backlight",
	.owner = THIS_MODULE,
	},
	.probe = pm860x_backlight_probe,
	.remove = pm860x_backlight_remove,
	};

	static int __init pm860x_backlight_init(void)
	{
	return platform_driver_register(&pm860x_backlight_driver);
	}
	module_init(pm860x_backlight_init);

	static void __exit pm860x_backlight_exit(void)
	{
	platform_driver_unregister(&pm860x_backlight_driver);
	}
	module_exit(pm860x_backlight_exit);

	MODULE_DESCRIPTION("Backlight Driver for Marvell Semiconductor 88PM8606");
	MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("platform:88pm860x-backlight");