/*
* Sanyo LV5207LP LED Driver
*
* Copyright (C) 2013 Ideas on board SPRL
*
* Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.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/backlight.h>
#include <linux/err.h>
#include <linux/fb.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/platform_data/lv5207lp.h>
#include <linux/slab.h>
#define LV5207LP_CTRL1 0x00
#define LV5207LP_CPSW (1 << 7)
#define LV5207LP_SCTEN (1 << 6)
#define LV5207LP_C10 (1 << 5)
#define LV5207LP_CKSW (1 << 4)
#define LV5207LP_RSW (1 << 3)
#define LV5207LP_GSW (1 << 2)
#define LV5207LP_BSW (1 << 1)
#define LV5207LP_CTRL2 0x01
#define LV5207LP_MSW (1 << 7)
#define LV5207LP_MLED4 (1 << 6)
#define LV5207LP_RED 0x02
#define LV5207LP_GREEN 0x03
#define LV5207LP_BLUE 0x04
#define LV5207LP_MAX_BRIGHTNESS 32
struct lv5207lp {
struct i2c_client *client;
struct backlight_device *backlight;
struct lv5207lp_platform_data *pdata;
};
static int lv5207lp_write(struct lv5207lp *lv, u8 reg, u8 data)
{
return i2c_smbus_write_byte_data(lv->client, reg, data);
}
static int lv5207lp_backlight_update_status(struct backlight_device *backlight)
{
struct lv5207lp *lv = bl_get_data(backlight);
int brightness = backlight->props.brightness;
if (backlight->props.power != FB_BLANK_UNBLANK ||
backlight->props.fb_blank != FB_BLANK_UNBLANK ||
backlight->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
brightness = 0;
if (brightness) {
lv5207lp_write(lv, LV5207LP_CTRL1,
LV5207LP_CPSW | LV5207LP_C10 | LV5207LP_CKSW);
lv5207lp_write(lv, LV5207LP_CTRL2,
LV5207LP_MSW | LV5207LP_MLED4 |
(brightness - 1));
} else {
lv5207lp_write(lv, LV5207LP_CTRL1, 0);
lv5207lp_write(lv, LV5207LP_CTRL2, 0);
}
return 0;
}
static int lv5207lp_backlight_check_fb(struct backlight_device *backlight,
struct fb_info *info)
{
struct lv5207lp *lv = bl_get_data(backlight);
return lv->pdata->fbdev == NULL || lv->pdata->fbdev == info->dev;
}
static const struct backlight_ops lv5207lp_backlight_ops = {
.options = BL_CORE_SUSPENDRESUME,
.update_status = lv5207lp_backlight_update_status,
.check_fb = lv5207lp_backlight_check_fb,
};
static int lv5207lp_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct lv5207lp_platform_data *pdata = dev_get_platdata(&client->dev);
struct backlight_device *backlight;
struct backlight_properties props;
struct lv5207lp *lv;
if (pdata == NULL) {
dev_err(&client->dev, "No platform data supplied\n");
return -EINVAL;
}
if (!i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_BYTE_DATA)) {
dev_warn(&client->dev,
"I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n");
return -EIO;
}
lv = devm_kzalloc(&client->dev, sizeof(*lv), GFP_KERNEL);
if (!lv)
return -ENOMEM;
lv->client = client;
lv->pdata = pdata;
memset(&props, 0, sizeof(props));
props.type = BACKLIGHT_RAW;
props.max_brightness = min_t(unsigned int, pdata->max_value,
LV5207LP_MAX_BRIGHTNESS);
props.brightness = clamp_t(unsigned int, pdata->def_value, 0,
props.max_brightness);
backlight = devm_backlight_device_register(&client->dev,
dev_name(&client->dev), &lv->client->dev,
lv, &lv5207lp_backlight_ops, &props);
if (IS_ERR(backlight)) {
dev_err(&client->dev, "failed to register backlight\n");
return PTR_ERR(backlight);
}
backlight_update_status(backlight);
i2c_set_clientdata(client, backlight);
return 0;
}
static int lv5207lp_remove(struct i2c_client *client)
{
struct backlight_device *backlight = i2c_get_clientdata(client);
backlight->props.brightness = 0;
backlight_update_status(backlight);
return 0;
}
static const struct i2c_device_id lv5207lp_ids[] = {
{ "lv5207lp", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, lv5207lp_ids);
static struct i2c_driver lv5207lp_driver = {
.driver = {
.name = "lv5207lp",
},
.probe = lv5207lp_probe,
.remove = lv5207lp_remove,
.id_table = lv5207lp_ids,
};
module_i2c_driver(lv5207lp_driver);
MODULE_DESCRIPTION("Sanyo LV5207LP Backlight Driver");
MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
MODULE_LICENSE("GPL");
