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/*
* LP5521/LP5523/LP55231 Common Driver
*
* Copyright 2012 Texas Instruments
*
* Author: Milo(Woogyom) Kim <milo.kim@ti.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.
*
* Derived from leds-lp5521.c, leds-lp5523.c
*/
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/platform_data/leds-lp55xx.h>
#include "leds-lp55xx-common.h"
static void lp55xx_reset_device(struct lp55xx_chip *chip)
{
struct lp55xx_device_config *cfg = chip->cfg;
u8 addr = cfg->reset.addr;
u8 val = cfg->reset.val;
/* no error checking here because no ACK from the device after reset */
lp55xx_write(chip, addr, val);
}
static int lp55xx_detect_device(struct lp55xx_chip *chip)
{
struct lp55xx_device_config *cfg = chip->cfg;
u8 addr = cfg->enable.addr;
u8 val = cfg->enable.val;
int ret;
ret = lp55xx_write(chip, addr, val);
if (ret)
return ret;
usleep_range(1000, 2000);
ret = lp55xx_read(chip, addr, &val);
if (ret)
return ret;
if (val != cfg->enable.val)
return -ENODEV;
return 0;
}
int lp55xx_write(struct lp55xx_chip *chip, u8 reg, u8 val)
{
return i2c_smbus_write_byte_data(chip->cl, reg, val);
}
EXPORT_SYMBOL_GPL(lp55xx_write);
int lp55xx_read(struct lp55xx_chip *chip, u8 reg, u8 *val)
{
s32 ret;
ret = i2c_smbus_read_byte_data(chip->cl, reg);
if (ret < 0)
return ret;
*val = ret;
return 0;
}
EXPORT_SYMBOL_GPL(lp55xx_read);
int lp55xx_update_bits(struct lp55xx_chip *chip, u8 reg, u8 mask, u8 val)
{
int ret;
u8 tmp;
ret = lp55xx_read(chip, reg, &tmp);
if (ret)
return ret;
tmp &= ~mask;
tmp |= val & mask;
return lp55xx_write(chip, reg, tmp);
}
EXPORT_SYMBOL_GPL(lp55xx_update_bits);
int lp55xx_init_device(struct lp55xx_chip *chip)
{
struct lp55xx_platform_data *pdata;
struct lp55xx_device_config *cfg;
struct device *dev = &chip->cl->dev;
int ret = 0;
WARN_ON(!chip);
pdata = chip->pdata;
cfg = chip->cfg;
if (!pdata || !cfg)
return -EINVAL;
if (pdata->setup_resources) {
ret = pdata->setup_resources();
if (ret < 0) {
dev_err(dev, "setup resoure err: %d\n", ret);
goto err;
}
}
if (pdata->enable) {
pdata->enable(0);
usleep_range(1000, 2000); /* Keep enable down at least 1ms */
pdata->enable(1);
usleep_range(1000, 2000); /* 500us abs min. */
}
lp55xx_reset_device(chip);
/*
* Exact value is not available. 10 - 20ms
* appears to be enough for reset.
*/
usleep_range(10000, 20000);
ret = lp55xx_detect_device(chip);
if (ret) {
dev_err(dev, "device detection err: %d\n", ret);
goto err;
}
err:
return ret;
}
EXPORT_SYMBOL_GPL(lp55xx_init_device);
MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
MODULE_DESCRIPTION("LP55xx Common Driver");
MODULE_LICENSE("GPL");
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