linux/drivers/video/backlight/tosa_bl.c
Wolfram Sang fbae3fb154 i2c: Remove all i2c_set_clientdata(client, NULL) in drivers
I2C drivers can use the clientdata-pointer to point to private data. As I2C
devices are not really unregistered, but merely detached from their driver, it
used to be the drivers obligation to clear this pointer during remove() or a
failed probe(). As a couple of drivers forgot to do this, it was agreed that it
was cleaner if the i2c-core does this clearance when appropriate, as there is
no guarantee for the lifetime of the clientdata-pointer after remove() anyhow.
This feature was added to the core with commit
e4a7b9b04d to fix the faulty drivers.

As there is no need anymore to clear the clientdata-pointer, remove all current
occurrences in the drivers to simplify the code and prevent confusion.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-06-03 11:33:58 +02:00

200 lines
4.2 KiB
C

/*
* LCD / Backlight control code for Sharp SL-6000x (tosa)
*
* Copyright (c) 2005 Dirk Opfer
* Copyright (c) 2007,2008 Dmitry Baryshkov
*
* 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/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/spi/spi.h>
#include <linux/i2c.h>
#include <linux/gpio.h>
#include <linux/fb.h>
#include <linux/backlight.h>
#include <linux/slab.h>
#include <asm/mach/sharpsl_param.h>
#include <mach/tosa.h>
#define COMADJ_DEFAULT 97
#define DAC_CH1 0
#define DAC_CH2 1
struct tosa_bl_data {
struct i2c_client *i2c;
struct backlight_device *bl;
int comadj;
};
static void tosa_bl_set_backlight(struct tosa_bl_data *data, int brightness)
{
struct spi_device *spi = data->i2c->dev.platform_data;
i2c_smbus_write_byte_data(data->i2c, DAC_CH1, data->comadj);
/* SetBacklightDuty */
i2c_smbus_write_byte_data(data->i2c, DAC_CH2, (u8)(brightness & 0xff));
/* SetBacklightVR */
gpio_set_value(TOSA_GPIO_BL_C20MA, brightness & 0x100);
tosa_bl_enable(spi, brightness);
}
static int tosa_bl_update_status(struct backlight_device *dev)
{
struct backlight_properties *props = &dev->props;
struct tosa_bl_data *data = dev_get_drvdata(&dev->dev);
int power = max(props->power, props->fb_blank);
int brightness = props->brightness;
if (power)
brightness = 0;
tosa_bl_set_backlight(data, brightness);
return 0;
}
static int tosa_bl_get_brightness(struct backlight_device *dev)
{
struct backlight_properties *props = &dev->props;
return props->brightness;
}
static const struct backlight_ops bl_ops = {
.get_brightness = tosa_bl_get_brightness,
.update_status = tosa_bl_update_status,
};
static int __devinit tosa_bl_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct backlight_properties props;
struct tosa_bl_data *data = kzalloc(sizeof(struct tosa_bl_data), GFP_KERNEL);
int ret = 0;
if (!data)
return -ENOMEM;
data->comadj = sharpsl_param.comadj == -1 ? COMADJ_DEFAULT : sharpsl_param.comadj;
ret = gpio_request(TOSA_GPIO_BL_C20MA, "backlight");
if (ret) {
dev_dbg(&data->bl->dev, "Unable to request gpio!\n");
goto err_gpio_bl;
}
ret = gpio_direction_output(TOSA_GPIO_BL_C20MA, 0);
if (ret)
goto err_gpio_dir;
i2c_set_clientdata(client, data);
data->i2c = client;
memset(&props, 0, sizeof(struct backlight_properties));
props.max_brightness = 512 - 1;
data->bl = backlight_device_register("tosa-bl", &client->dev, data,
&bl_ops, &props);
if (IS_ERR(data->bl)) {
ret = PTR_ERR(data->bl);
goto err_reg;
}
data->bl->props.brightness = 69;
data->bl->props.power = FB_BLANK_UNBLANK;
backlight_update_status(data->bl);
return 0;
err_reg:
data->bl = NULL;
err_gpio_dir:
gpio_free(TOSA_GPIO_BL_C20MA);
err_gpio_bl:
kfree(data);
return ret;
}
static int __devexit tosa_bl_remove(struct i2c_client *client)
{
struct tosa_bl_data *data = i2c_get_clientdata(client);
backlight_device_unregister(data->bl);
data->bl = NULL;
gpio_free(TOSA_GPIO_BL_C20MA);
kfree(data);
return 0;
}
#ifdef CONFIG_PM
static int tosa_bl_suspend(struct i2c_client *client, pm_message_t pm)
{
struct tosa_bl_data *data = i2c_get_clientdata(client);
tosa_bl_set_backlight(data, 0);
return 0;
}
static int tosa_bl_resume(struct i2c_client *client)
{
struct tosa_bl_data *data = i2c_get_clientdata(client);
backlight_update_status(data->bl);
return 0;
}
#else
#define tosa_bl_suspend NULL
#define tosa_bl_resume NULL
#endif
static const struct i2c_device_id tosa_bl_id[] = {
{ "tosa-bl", 0 },
{ },
};
static struct i2c_driver tosa_bl_driver = {
.driver = {
.name = "tosa-bl",
.owner = THIS_MODULE,
},
.probe = tosa_bl_probe,
.remove = __devexit_p(tosa_bl_remove),
.suspend = tosa_bl_suspend,
.resume = tosa_bl_resume,
.id_table = tosa_bl_id,
};
static int __init tosa_bl_init(void)
{
return i2c_add_driver(&tosa_bl_driver);
}
static void __exit tosa_bl_exit(void)
{
i2c_del_driver(&tosa_bl_driver);
}
module_init(tosa_bl_init);
module_exit(tosa_bl_exit);
MODULE_AUTHOR("Dmitry Baryshkov");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("LCD/Backlight control for Sharp SL-6000 PDA");