/*
* Copyright (c) 2015 Intel Corporation
*
* Driver for UPISEMI us5182d Proximity and Ambient Light Sensor.
*
* 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.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* To do: Interrupt support.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/acpi.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/mutex.h>
#define US5182D_REG_CFG0 0x00
#define US5182D_CFG0_ONESHOT_EN BIT(6)
#define US5182D_CFG0_SHUTDOWN_EN BIT(7)
#define US5182D_CFG0_WORD_ENABLE BIT(0)
#define US5182D_REG_CFG1 0x01
#define US5182D_CFG1_ALS_RES16 BIT(4)
#define US5182D_CFG1_AGAIN_DEFAULT 0x00
#define US5182D_REG_CFG2 0x02
#define US5182D_CFG2_PX_RES16 BIT(4)
#define US5182D_CFG2_PXGAIN_DEFAULT BIT(2)
#define US5182D_REG_CFG3 0x03
#define US5182D_CFG3_LED_CURRENT100 (BIT(4) | BIT(5))
#define US5182D_REG_CFG4 0x10
/*
* Registers for tuning the auto dark current cancelling feature.
* DARK_TH(reg 0x27,0x28) - threshold (counts) for auto dark cancelling.
* when ALS > DARK_TH --> ALS_Code = ALS - Upper(0x2A) * Dark
* when ALS < DARK_TH --> ALS_Code = ALS - Lower(0x29) * Dark
*/
#define US5182D_REG_UDARK_TH 0x27
#define US5182D_REG_DARK_AUTO_EN 0x2b
#define US5182D_REG_AUTO_LDARK_GAIN 0x29
#define US5182D_REG_AUTO_HDARK_GAIN 0x2a
#define US5182D_OPMODE_ALS 0x01
#define US5182D_OPMODE_PX 0x02
#define US5182D_OPMODE_SHIFT 4
#define US5182D_REG_DARK_AUTO_EN_DEFAULT 0x80
#define US5182D_REG_AUTO_LDARK_GAIN_DEFAULT 0x16
#define US5182D_REG_AUTO_HDARK_GAIN_DEFAULT 0x00
#define US5182D_REG_ADL 0x0c
#define US5182D_REG_PDL 0x0e
#define US5182D_REG_MODE_STORE 0x21
#define US5182D_STORE_MODE 0x01
#define US5182D_REG_CHIPID 0xb2
#define US5182D_OPMODE_MASK GENMASK(5, 4)
#define US5182D_AGAIN_MASK 0x07
#define US5182D_RESET_CHIP 0x01
#define US5182D_CHIPID 0x26
#define US5182D_DRV_NAME "us5182d"
#define US5182D_GA_RESOLUTION 1000
#define US5182D_READ_BYTE 1
#define US5182D_READ_WORD 2
#define US5182D_OPSTORE_SLEEP_TIME 20 /* ms */
/* Available ranges: [12354, 7065, 3998, 2202, 1285, 498, 256, 138] lux */
static const int us5182d_scales[] = {188500, 107800, 61000, 33600, 19600, 7600,
3900, 2100};
/*
* Experimental thresholds that work with US5182D sensor on evaluation board
* roughly between 12-32 lux
*/
static u16 us5182d_dark_ths_vals[] = {170, 200, 512, 512, 800, 2000, 4000,
8000};
enum mode {
US5182D_ALS_PX,
US5182D_ALS_ONLY,
US5182D_PX_ONLY
};
struct us5182d_data {
struct i2c_client *client;
struct mutex lock;
/* Glass attenuation factor */
u32 ga;
/* Dark gain tuning */
u8 lower_dark_gain;
u8 upper_dark_gain;
u16 *us5182d_dark_ths;
u8 opmode;
};
static IIO_CONST_ATTR(in_illuminance_scale_available,
"0.0021 0.0039 0.0076 0.0196 0.0336 0.061 0.1078 0.1885");
static struct attribute *us5182d_attrs[] = {
&iio_const_attr_in_illuminance_scale_available.dev_attr.attr,
NULL
};
static const struct attribute_group us5182d_attr_group = {
.attrs = us5182d_attrs,
};
static const struct {
u8 reg;
u8 val;
} us5182d_regvals[] = {
{US5182D_REG_CFG0, (US5182D_CFG0_SHUTDOWN_EN |
US5182D_CFG0_WORD_ENABLE)},
{US5182D_REG_CFG1, US5182D_CFG1_ALS_RES16},
{US5182D_REG_CFG2, (US5182D_CFG2_PX_RES16 |
US5182D_CFG2_PXGAIN_DEFAULT)},
{US5182D_REG_CFG3, US5182D_CFG3_LED_CURRENT100},
{US5182D_REG_MODE_STORE, US5182D_STORE_MODE},
{US5182D_REG_CFG4, 0x00},
};
static const struct iio_chan_spec us5182d_channels[] = {
{
.type = IIO_LIGHT,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
},
{
.type = IIO_PROXIMITY,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
}
};
static int us5182d_get_als(struct us5182d_data *data)
{
int ret;
unsigned long result;
ret = i2c_smbus_read_word_data(data->client,
US5182D_REG_ADL);
if (ret < 0)
return ret;
result = ret * data->ga / US5182D_GA_RESOLUTION;
if (result > 0xffff)
result = 0xffff;
return result;
}
static int us5182d_set_opmode(struct us5182d_data *data, u8 mode)
{
int ret;
ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CFG0);
if (ret < 0)
return ret;
/*
* In oneshot mode the chip will power itself down after taking the
* required measurement.
*/
ret = ret | US5182D_CFG0_ONESHOT_EN;
/* update mode */
ret = ret & ~US5182D_OPMODE_MASK;
ret = ret | (mode << US5182D_OPMODE_SHIFT);
/*
* After updating the operating mode, the chip requires that
* the operation is stored, by writing 1 in the STORE_MODE
* register (auto-clearing).
*/
ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_CFG0, ret);
if (ret < 0)
return ret;
if (mode == data->opmode)
return 0;
ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_MODE_STORE,
US5182D_STORE_MODE);
if (ret < 0)
return ret;
data->opmode = mode;
msleep(US5182D_OPSTORE_SLEEP_TIME);
return 0;
}
static int us5182d_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int *val,
int *val2, long mask)
{
struct us5182d_data *data = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
switch (chan->type) {
case IIO_LIGHT:
mutex_lock(&data->lock);
ret = us5182d_set_opmode(data, US5182D_OPMODE_ALS);
if (ret < 0)
goto out_err;
ret = us5182d_get_als(data);
if (ret < 0)
goto out_err;
mutex_unlock(&data->lock);
*val = ret;
return IIO_VAL_INT;
case IIO_PROXIMITY:
mutex_lock(&data->lock);
ret = us5182d_set_opmode(data, US5182D_OPMODE_PX);
if (ret < 0)
goto out_err;
ret = i2c_smbus_read_word_data(data->client,
US5182D_REG_PDL);
if (ret < 0)
goto out_err;
mutex_unlock(&data->lock);
*val = ret;
return IIO_VAL_INT;
default:
return -EINVAL;
}
case IIO_CHAN_INFO_SCALE:
ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CFG1);
if (ret < 0)
return ret;
*val = 0;
*val2 = us5182d_scales[ret & US5182D_AGAIN_MASK];
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
return -EINVAL;
out_err:
mutex_unlock(&data->lock);
return ret;
}
/**
* us5182d_update_dark_th - update Darh_Th registers
* @data us5182d_data structure
* @index index in us5182d_dark_ths array to use for the updated value
*
* Function needs to be called with a lock held because it needs two i2c write
* byte operations as these registers (0x27 0x28) don't work in word mode
* accessing.
*/
static int us5182d_update_dark_th(struct us5182d_data *data, int index)
{
__be16 dark_th = cpu_to_be16(data->us5182d_dark_ths[index]);
int ret;
ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_UDARK_TH,
((u8 *)&dark_th)[0]);
if (ret < 0)
return ret;
return i2c_smbus_write_byte_data(data->client, US5182D_REG_UDARK_TH + 1,
((u8 *)&dark_th)[1]);
}
/**
* us5182d_apply_scale - update the ALS scale
* @data us5182d_data structure
* @index index in us5182d_scales array to use for the updated value
*
* Function needs to be called with a lock held as we're having more than one
* i2c operation.
*/
static int us5182d_apply_scale(struct us5182d_data *data, int index)
{
int ret;
ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CFG1);
if (ret < 0)
return ret;
ret = ret & (~US5182D_AGAIN_MASK);
ret |= index;
ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_CFG1, ret);
if (ret < 0)
return ret;
return us5182d_update_dark_th(data, index);
}
static int us5182d_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int val,
int val2, long mask)
{
struct us5182d_data *data = iio_priv(indio_dev);
int ret, i;
switch (mask) {
case IIO_CHAN_INFO_SCALE:
if (val != 0)
return -EINVAL;
for (i = 0; i < ARRAY_SIZE(us5182d_scales); i++)
if (val2 == us5182d_scales[i]) {
mutex_lock(&data->lock);
ret = us5182d_apply_scale(data, i);
mutex_unlock(&data->lock);
return ret;
}
break;
default:
return -EINVAL;
}
return -EINVAL;
}
static const struct iio_info us5182d_info = {
.driver_module = THIS_MODULE,
.read_raw = us5182d_read_raw,
.write_raw = us5182d_write_raw,
.attrs = &us5182d_attr_group,
};
static int us5182d_reset(struct iio_dev *indio_dev)
{
struct us5182d_data *data = iio_priv(indio_dev);
return i2c_smbus_write_byte_data(data->client, US5182D_REG_CFG3,
US5182D_RESET_CHIP);
}
static int us5182d_init(struct iio_dev *indio_dev)
{
struct us5182d_data *data = iio_priv(indio_dev);
int i, ret;
ret = us5182d_reset(indio_dev);
if (ret < 0)
return ret;
data->opmode = 0;
for (i = 0; i < ARRAY_SIZE(us5182d_regvals); i++) {
ret = i2c_smbus_write_byte_data(data->client,
us5182d_regvals[i].reg,
us5182d_regvals[i].val);
if (ret < 0)
return ret;
}
return 0;
}
static void us5182d_get_platform_data(struct iio_dev *indio_dev)
{
struct us5182d_data *data = iio_priv(indio_dev);
if (device_property_read_u32(&data->client->dev, "upisemi,glass-coef",
&data->ga))
data->ga = US5182D_GA_RESOLUTION;
if (device_property_read_u16_array(&data->client->dev,
"upisemi,dark-ths",
data->us5182d_dark_ths,
ARRAY_SIZE(us5182d_dark_ths_vals)))
data->us5182d_dark_ths = us5182d_dark_ths_vals;
if (device_property_read_u8(&data->client->dev,
"upisemi,upper-dark-gain",
&data->upper_dark_gain))
data->upper_dark_gain = US5182D_REG_AUTO_HDARK_GAIN_DEFAULT;
if (device_property_read_u8(&data->client->dev,
"upisemi,lower-dark-gain",
&data->lower_dark_gain))
data->lower_dark_gain = US5182D_REG_AUTO_LDARK_GAIN_DEFAULT;
}
static int us5182d_dark_gain_config(struct iio_dev *indio_dev)
{
struct us5182d_data *data = iio_priv(indio_dev);
int ret;
ret = us5182d_update_dark_th(data, US5182D_CFG1_AGAIN_DEFAULT);
if (ret < 0)
return ret;
ret = i2c_smbus_write_byte_data(data->client,
US5182D_REG_AUTO_LDARK_GAIN,
data->lower_dark_gain);
if (ret < 0)
return ret;
ret = i2c_smbus_write_byte_data(data->client,
US5182D_REG_AUTO_HDARK_GAIN,
data->upper_dark_gain);
if (ret < 0)
return ret;
return i2c_smbus_write_byte_data(data->client, US5182D_REG_DARK_AUTO_EN,
US5182D_REG_DARK_AUTO_EN_DEFAULT);
}
static int us5182d_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct us5182d_data *data;
struct iio_dev *indio_dev;
int ret;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
data = iio_priv(indio_dev);
i2c_set_clientdata(client, indio_dev);
data->client = client;
mutex_init(&data->lock);
indio_dev->dev.parent = &client->dev;
indio_dev->info = &us5182d_info;
indio_dev->name = US5182D_DRV_NAME;
indio_dev->channels = us5182d_channels;
indio_dev->num_channels = ARRAY_SIZE(us5182d_channels);
indio_dev->modes = INDIO_DIRECT_MODE;
ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CHIPID);
if (ret != US5182D_CHIPID) {
dev_err(&data->client->dev,
"Failed to detect US5182 light chip\n");
return (ret < 0) ? ret : -ENODEV;
}
us5182d_get_platform_data(indio_dev);
ret = us5182d_init(indio_dev);
if (ret < 0)
return ret;
ret = us5182d_dark_gain_config(indio_dev);
if (ret < 0)
return ret;
return iio_device_register(indio_dev);
}
static int us5182d_remove(struct i2c_client *client)
{
iio_device_unregister(i2c_get_clientdata(client));
return i2c_smbus_write_byte_data(client, US5182D_REG_CFG0,
US5182D_CFG0_SHUTDOWN_EN);
}
static const struct acpi_device_id us5182d_acpi_match[] = {
{ "USD5182", 0},
{}
};
MODULE_DEVICE_TABLE(acpi, us5182d_acpi_match);
static const struct i2c_device_id us5182d_id[] = {
{"usd5182", 0},
{}
};
MODULE_DEVICE_TABLE(i2c, us5182d_id);
static struct i2c_driver us5182d_driver = {
.driver = {
.name = US5182D_DRV_NAME,
.acpi_match_table = ACPI_PTR(us5182d_acpi_match),
},
.probe = us5182d_probe,
.remove = us5182d_remove,
.id_table = us5182d_id,
};
module_i2c_driver(us5182d_driver);
MODULE_AUTHOR("Adriana Reus <adriana.reus@intel.com>");
MODULE_DESCRIPTION("Driver for us5182d Proximity and Light Sensor");
MODULE_LICENSE("GPL v2");