kernel_optimize_test/drivers/video/backlight/lm3639_bl.c
Jingoo Han 3033d2c0dd backlight: lm3639: Remove unnecessary return statements
Fixed the following checkpatch warning.

  WARNING: void function return statements are not generally useful

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-08-29 08:25:23 +01:00

433 lines
10 KiB
C

/*
* Simple driver for Texas Instruments LM3639 Backlight + Flash LED driver chip
* Copyright (C) 2012 Texas Instruments
*
* 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/module.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/backlight.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/uaccess.h>
#include <linux/interrupt.h>
#include <linux/regmap.h>
#include <linux/platform_data/lm3639_bl.h>
#define REG_DEV_ID 0x00
#define REG_CHECKSUM 0x01
#define REG_BL_CONF_1 0x02
#define REG_BL_CONF_2 0x03
#define REG_BL_CONF_3 0x04
#define REG_BL_CONF_4 0x05
#define REG_FL_CONF_1 0x06
#define REG_FL_CONF_2 0x07
#define REG_FL_CONF_3 0x08
#define REG_IO_CTRL 0x09
#define REG_ENABLE 0x0A
#define REG_FLAG 0x0B
#define REG_MAX REG_FLAG
struct lm3639_chip_data {
struct device *dev;
struct lm3639_platform_data *pdata;
struct backlight_device *bled;
struct led_classdev cdev_flash;
struct led_classdev cdev_torch;
struct regmap *regmap;
unsigned int bled_mode;
unsigned int bled_map;
unsigned int last_flag;
};
/* initialize chip */
static int lm3639_chip_init(struct lm3639_chip_data *pchip)
{
int ret;
unsigned int reg_val;
struct lm3639_platform_data *pdata = pchip->pdata;
/* input pins config. */
ret =
regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x08,
pdata->pin_pwm);
if (ret < 0)
goto out;
reg_val = (pdata->pin_pwm & 0x40) | pdata->pin_strobe | pdata->pin_tx;
ret = regmap_update_bits(pchip->regmap, REG_IO_CTRL, 0x7C, reg_val);
if (ret < 0)
goto out;
/* init brightness */
ret = regmap_write(pchip->regmap, REG_BL_CONF_4, pdata->init_brt_led);
if (ret < 0)
goto out;
ret = regmap_write(pchip->regmap, REG_BL_CONF_3, pdata->init_brt_led);
if (ret < 0)
goto out;
/* output pins config. */
if (!pdata->init_brt_led) {
reg_val = pdata->fled_pins;
reg_val |= pdata->bled_pins;
} else {
reg_val = pdata->fled_pins;
reg_val |= pdata->bled_pins | 0x01;
}
ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x79, reg_val);
if (ret < 0)
goto out;
return ret;
out:
dev_err(pchip->dev, "i2c failed to access register\n");
return ret;
}
/* update and get brightness */
static int lm3639_bled_update_status(struct backlight_device *bl)
{
int ret;
unsigned int reg_val;
struct lm3639_chip_data *pchip = bl_get_data(bl);
struct lm3639_platform_data *pdata = pchip->pdata;
ret = regmap_read(pchip->regmap, REG_FLAG, &reg_val);
if (ret < 0)
goto out;
if (reg_val != 0)
dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);
/* pwm control */
if (pdata->pin_pwm) {
if (pdata->pwm_set_intensity)
pdata->pwm_set_intensity(bl->props.brightness,
pdata->max_brt_led);
else
dev_err(pchip->dev,
"No pwm control func. in plat-data\n");
return bl->props.brightness;
}
/* i2c control and set brigtness */
ret = regmap_write(pchip->regmap, REG_BL_CONF_4, bl->props.brightness);
if (ret < 0)
goto out;
ret = regmap_write(pchip->regmap, REG_BL_CONF_3, bl->props.brightness);
if (ret < 0)
goto out;
if (!bl->props.brightness)
ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x01, 0x00);
else
ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x01, 0x01);
if (ret < 0)
goto out;
return bl->props.brightness;
out:
dev_err(pchip->dev, "i2c failed to access registers\n");
return bl->props.brightness;
}
static int lm3639_bled_get_brightness(struct backlight_device *bl)
{
int ret;
unsigned int reg_val;
struct lm3639_chip_data *pchip = bl_get_data(bl);
struct lm3639_platform_data *pdata = pchip->pdata;
if (pdata->pin_pwm) {
if (pdata->pwm_get_intensity)
bl->props.brightness = pdata->pwm_get_intensity();
else
dev_err(pchip->dev,
"No pwm control func. in plat-data\n");
return bl->props.brightness;
}
ret = regmap_read(pchip->regmap, REG_BL_CONF_1, &reg_val);
if (ret < 0)
goto out;
if (reg_val & 0x10)
ret = regmap_read(pchip->regmap, REG_BL_CONF_4, &reg_val);
else
ret = regmap_read(pchip->regmap, REG_BL_CONF_3, &reg_val);
if (ret < 0)
goto out;
bl->props.brightness = reg_val;
return bl->props.brightness;
out:
dev_err(pchip->dev, "i2c failed to access register\n");
return bl->props.brightness;
}
static const struct backlight_ops lm3639_bled_ops = {
.options = BL_CORE_SUSPENDRESUME,
.update_status = lm3639_bled_update_status,
.get_brightness = lm3639_bled_get_brightness,
};
/* backlight mapping mode */
static ssize_t lm3639_bled_mode_store(struct device *dev,
struct device_attribute *devAttr,
const char *buf, size_t size)
{
ssize_t ret;
struct lm3639_chip_data *pchip = dev_get_drvdata(dev);
unsigned int state;
ret = kstrtouint(buf, 10, &state);
if (ret)
goto out_input;
if (!state)
ret =
regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x10,
0x00);
else
ret =
regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x10,
0x10);
if (ret < 0)
goto out;
return size;
out:
dev_err(pchip->dev, "%s:i2c access fail to register\n", __func__);
return ret;
out_input:
dev_err(pchip->dev, "%s:input conversion fail\n", __func__);
return ret;
}
static DEVICE_ATTR(bled_mode, S_IWUSR, NULL, lm3639_bled_mode_store);
/* torch */
static void lm3639_torch_brightness_set(struct led_classdev *cdev,
enum led_brightness brightness)
{
int ret;
unsigned int reg_val;
struct lm3639_chip_data *pchip;
pchip = container_of(cdev, struct lm3639_chip_data, cdev_torch);
ret = regmap_read(pchip->regmap, REG_FLAG, &reg_val);
if (ret < 0)
goto out;
if (reg_val != 0)
dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);
/* brightness 0 means off state */
if (!brightness) {
ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x00);
if (ret < 0)
goto out;
return;
}
ret = regmap_update_bits(pchip->regmap,
REG_FL_CONF_1, 0x70, (brightness - 1) << 4);
if (ret < 0)
goto out;
ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x02);
if (ret < 0)
goto out;
return;
out:
dev_err(pchip->dev, "i2c failed to access register\n");
}
/* flash */
static void lm3639_flash_brightness_set(struct led_classdev *cdev,
enum led_brightness brightness)
{
int ret;
unsigned int reg_val;
struct lm3639_chip_data *pchip;
pchip = container_of(cdev, struct lm3639_chip_data, cdev_flash);
ret = regmap_read(pchip->regmap, REG_FLAG, &reg_val);
if (ret < 0)
goto out;
if (reg_val != 0)
dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);
/* torch off before flash control */
ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x00);
if (ret < 0)
goto out;
/* brightness 0 means off state */
if (!brightness)
return;
ret = regmap_update_bits(pchip->regmap,
REG_FL_CONF_1, 0x0F, brightness - 1);
if (ret < 0)
goto out;
ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x06);
if (ret < 0)
goto out;
return;
out:
dev_err(pchip->dev, "i2c failed to access register\n");
}
static const struct regmap_config lm3639_regmap = {
.reg_bits = 8,
.val_bits = 8,
.max_register = REG_MAX,
};
static int lm3639_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int ret;
struct lm3639_chip_data *pchip;
struct lm3639_platform_data *pdata = dev_get_platdata(&client->dev);
struct backlight_properties props;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
dev_err(&client->dev, "i2c functionality check fail.\n");
return -EOPNOTSUPP;
}
if (pdata == NULL) {
dev_err(&client->dev, "Needs Platform Data.\n");
return -ENODATA;
}
pchip = devm_kzalloc(&client->dev,
sizeof(struct lm3639_chip_data), GFP_KERNEL);
if (!pchip)
return -ENOMEM;
pchip->pdata = pdata;
pchip->dev = &client->dev;
pchip->regmap = devm_regmap_init_i2c(client, &lm3639_regmap);
if (IS_ERR(pchip->regmap)) {
ret = PTR_ERR(pchip->regmap);
dev_err(&client->dev, "fail : allocate register map: %d\n",
ret);
return ret;
}
i2c_set_clientdata(client, pchip);
/* chip initialize */
ret = lm3639_chip_init(pchip);
if (ret < 0) {
dev_err(&client->dev, "fail : chip init\n");
goto err_out;
}
/* backlight */
props.type = BACKLIGHT_RAW;
props.brightness = pdata->init_brt_led;
props.max_brightness = pdata->max_brt_led;
pchip->bled =
devm_backlight_device_register(pchip->dev, "lm3639_bled",
pchip->dev, pchip, &lm3639_bled_ops,
&props);
if (IS_ERR(pchip->bled)) {
dev_err(&client->dev, "fail : backlight register\n");
ret = PTR_ERR(pchip->bled);
goto err_out;
}
ret = device_create_file(&(pchip->bled->dev), &dev_attr_bled_mode);
if (ret < 0) {
dev_err(&client->dev, "failed : add sysfs entries\n");
goto err_out;
}
/* flash */
pchip->cdev_flash.name = "lm3639_flash";
pchip->cdev_flash.max_brightness = 16;
pchip->cdev_flash.brightness_set = lm3639_flash_brightness_set;
ret = led_classdev_register((struct device *)
&client->dev, &pchip->cdev_flash);
if (ret < 0) {
dev_err(&client->dev, "fail : flash register\n");
goto err_flash;
}
/* torch */
pchip->cdev_torch.name = "lm3639_torch";
pchip->cdev_torch.max_brightness = 8;
pchip->cdev_torch.brightness_set = lm3639_torch_brightness_set;
ret = led_classdev_register((struct device *)
&client->dev, &pchip->cdev_torch);
if (ret < 0) {
dev_err(&client->dev, "fail : torch register\n");
goto err_torch;
}
return 0;
err_torch:
led_classdev_unregister(&pchip->cdev_flash);
err_flash:
device_remove_file(&(pchip->bled->dev), &dev_attr_bled_mode);
err_out:
return ret;
}
static int lm3639_remove(struct i2c_client *client)
{
struct lm3639_chip_data *pchip = i2c_get_clientdata(client);
regmap_write(pchip->regmap, REG_ENABLE, 0x00);
if (&pchip->cdev_torch)
led_classdev_unregister(&pchip->cdev_torch);
if (&pchip->cdev_flash)
led_classdev_unregister(&pchip->cdev_flash);
if (pchip->bled)
device_remove_file(&(pchip->bled->dev), &dev_attr_bled_mode);
return 0;
}
static const struct i2c_device_id lm3639_id[] = {
{LM3639_NAME, 0},
{}
};
MODULE_DEVICE_TABLE(i2c, lm3639_id);
static struct i2c_driver lm3639_i2c_driver = {
.driver = {
.name = LM3639_NAME,
},
.probe = lm3639_probe,
.remove = lm3639_remove,
.id_table = lm3639_id,
};
module_i2c_driver(lm3639_i2c_driver);
MODULE_DESCRIPTION("Texas Instruments Backlight+Flash LED driver for LM3639");
MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>");
MODULE_AUTHOR("Ldd Mlp <ldd-mlp@list.ti.com>");
MODULE_LICENSE("GPL v2");