[PATCH v2 06/09] backlight: enable backlight in 88pm860x

Samuel Ortiz sameo at linux.intel.com
Fri Jan 8 06:06:47 EST 2010


Hi Haojian, Richard,

On Wed, Dec 09, 2009 at 08:15:28AM -0500, Haojian Zhuang wrote:
> From 8d2bc9826f758f113fde6f3fd01723111fbf2a91 Mon Sep 17 00:00:00 2001
> From: Haojian Zhuang <haojian.zhuang at marvell.com>
> Date: Mon, 9 Nov 2009 12:41:07 -0500
> Subject: [PATCH] backlight: enable backlight in 88pm860x
> 
> At most, three backlight device can be supported in 88pm860x driver.
I applied this patch and the LED one to my for-next branch.
Richard, whenever you have time for that, could you please quickly check if
they oook ok to you ? They're 2.6.34 material, so no rush here.

Cheers,
Samuel.


> Signed-off-by: Haojian Zhuang <haojian.zhuang at marvell.com>
> ---
>  drivers/video/backlight/88pm860x_bl.c |  304 +++++++++++++++++++++++++++++++++
>  drivers/video/backlight/Kconfig       |    6 +
>  drivers/video/backlight/Makefile      |    1 +
>  3 files changed, 311 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/video/backlight/88pm860x_bl.c
> 
> diff --git a/drivers/video/backlight/88pm860x_bl.c
> b/drivers/video/backlight/88pm860x_bl.c
> new file mode 100644
> index 0000000..b8f705c
> --- /dev/null
> +++ b/drivers/video/backlight/88pm860x_bl.c
> @@ -0,0 +1,304 @@
> +/*
> + * Backlight driver for Marvell Semiconductor 88PM8606
> + *
> + * Copyright (C) 2009 Marvell International Ltd.
> + *	Haojian Zhuang <haojian.zhuang at 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>
> +
> +#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;
> +	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");
> +		return -EINVAL;
> +	}
> +
> +	bl = backlight_device_register(name, &pdev->dev, data,
> +					&pm860x_backlight_ops);
> +	if (IS_ERR(bl)) {
> +		dev_err(&pdev->dev, "failed to register backlight\n");
> +		kfree(data);
> +		return PTR_ERR(bl);
> +	}
> +	bl->props.max_brightness = MAX_BRIGHTNESS;
> +	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:
> +	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 at marvell.com>");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:88pm860x-backlight");
> diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
> index 09bfa96..96a6b30 100644
> --- a/drivers/video/backlight/Kconfig
> +++ b/drivers/video/backlight/Kconfig
> @@ -262,3 +262,9 @@ config BACKLIGHT_ADP5520
>  	  To compile this driver as a module, choose M here: the module will
>  	  be called adp5520_bl.
> 
> +config BACKLIGHT_88PM860X
> +	tristate "Backlight Driver for 88PM8606 using WLED"
> +	depends on BACKLIGHT_CLASS_DEVICE && MFD_88PM860X
> +	help
> +	  Say Y to enable the backlight driver for Marvell 88PM8606.
> +
> diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
> index 9a40554..802d467 100644
> --- a/drivers/video/backlight/Makefile
> +++ b/drivers/video/backlight/Makefile
> @@ -28,4 +28,5 @@ obj-$(CONFIG_BACKLIGHT_SAHARA)	+= kb3886_bl.o
>  obj-$(CONFIG_BACKLIGHT_WM831X)	+= wm831x_bl.o
>  obj-$(CONFIG_BACKLIGHT_ADX)    += adx_bl.o
>  obj-$(CONFIG_BACKLIGHT_ADP5520)	+= adp5520_bl.o
> +obj-$(CONFIG_BACKLIGHT_88PM860X) += 88pm860x_bl.o
> 
> -- 
> 1.5.6.5

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