![Jonathan Cameron](/assets/img/avatar_default.png)
The equivalent of both of these are now done via macro magic when the relevant register calls are made. The actual structure elements will shortly go away. Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
319 lines
7.5 KiB
C
319 lines
7.5 KiB
C
/*
|
|
* Copyright (c) 2016 Marek Vasut <marex@denx.de>
|
|
*
|
|
* Driver for Hope RF HP03 digital temperature and pressure 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.
|
|
*/
|
|
|
|
#define pr_fmt(fmt) "hp03: " fmt
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/gpio/consumer.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/regmap.h>
|
|
#include <linux/iio/iio.h>
|
|
#include <linux/iio/sysfs.h>
|
|
|
|
/*
|
|
* The HP03 sensor occupies two fixed I2C addresses:
|
|
* 0x50 ... read-only EEPROM with calibration data
|
|
* 0x77 ... read-write ADC for pressure and temperature
|
|
*/
|
|
#define HP03_EEPROM_ADDR 0x50
|
|
#define HP03_ADC_ADDR 0x77
|
|
|
|
#define HP03_EEPROM_CX_OFFSET 0x10
|
|
#define HP03_EEPROM_AB_OFFSET 0x1e
|
|
#define HP03_EEPROM_CD_OFFSET 0x20
|
|
|
|
#define HP03_ADC_WRITE_REG 0xff
|
|
#define HP03_ADC_READ_REG 0xfd
|
|
#define HP03_ADC_READ_PRESSURE 0xf0 /* D1 in datasheet */
|
|
#define HP03_ADC_READ_TEMP 0xe8 /* D2 in datasheet */
|
|
|
|
struct hp03_priv {
|
|
struct i2c_client *client;
|
|
struct mutex lock;
|
|
struct gpio_desc *xclr_gpio;
|
|
|
|
struct i2c_client *eeprom_client;
|
|
struct regmap *eeprom_regmap;
|
|
|
|
s32 pressure; /* kPa */
|
|
s32 temp; /* Deg. C */
|
|
};
|
|
|
|
static const struct iio_chan_spec hp03_channels[] = {
|
|
{
|
|
.type = IIO_PRESSURE,
|
|
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
|
|
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
|
|
},
|
|
{
|
|
.type = IIO_TEMP,
|
|
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
|
|
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
|
|
},
|
|
};
|
|
|
|
static bool hp03_is_writeable_reg(struct device *dev, unsigned int reg)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
static bool hp03_is_volatile_reg(struct device *dev, unsigned int reg)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
static const struct regmap_config hp03_regmap_config = {
|
|
.reg_bits = 8,
|
|
.val_bits = 8,
|
|
|
|
.max_register = HP03_EEPROM_CD_OFFSET + 1,
|
|
.cache_type = REGCACHE_RBTREE,
|
|
|
|
.writeable_reg = hp03_is_writeable_reg,
|
|
.volatile_reg = hp03_is_volatile_reg,
|
|
};
|
|
|
|
static int hp03_get_temp_pressure(struct hp03_priv *priv, const u8 reg)
|
|
{
|
|
int ret;
|
|
|
|
ret = i2c_smbus_write_byte_data(priv->client, HP03_ADC_WRITE_REG, reg);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
msleep(50); /* Wait for conversion to finish */
|
|
|
|
return i2c_smbus_read_word_data(priv->client, HP03_ADC_READ_REG);
|
|
}
|
|
|
|
static int hp03_update_temp_pressure(struct hp03_priv *priv)
|
|
{
|
|
struct device *dev = &priv->client->dev;
|
|
u8 coefs[18];
|
|
u16 cx_val[7];
|
|
int ab_val, d1_val, d2_val, diff_val, dut, off, sens, x;
|
|
int i, ret;
|
|
|
|
/* Sample coefficients from EEPROM */
|
|
ret = regmap_bulk_read(priv->eeprom_regmap, HP03_EEPROM_CX_OFFSET,
|
|
coefs, sizeof(coefs));
|
|
if (ret < 0) {
|
|
dev_err(dev, "Failed to read EEPROM (reg=%02x)\n",
|
|
HP03_EEPROM_CX_OFFSET);
|
|
return ret;
|
|
}
|
|
|
|
/* Sample Temperature and Pressure */
|
|
gpiod_set_value_cansleep(priv->xclr_gpio, 1);
|
|
|
|
ret = hp03_get_temp_pressure(priv, HP03_ADC_READ_PRESSURE);
|
|
if (ret < 0) {
|
|
dev_err(dev, "Failed to read pressure\n");
|
|
goto err_adc;
|
|
}
|
|
d1_val = ret;
|
|
|
|
ret = hp03_get_temp_pressure(priv, HP03_ADC_READ_TEMP);
|
|
if (ret < 0) {
|
|
dev_err(dev, "Failed to read temperature\n");
|
|
goto err_adc;
|
|
}
|
|
d2_val = ret;
|
|
|
|
gpiod_set_value_cansleep(priv->xclr_gpio, 0);
|
|
|
|
/* The Cx coefficients and Temp/Pressure values are MSB first. */
|
|
for (i = 0; i < 7; i++)
|
|
cx_val[i] = (coefs[2 * i] << 8) | (coefs[(2 * i) + 1] << 0);
|
|
d1_val = ((d1_val >> 8) & 0xff) | ((d1_val & 0xff) << 8);
|
|
d2_val = ((d2_val >> 8) & 0xff) | ((d2_val & 0xff) << 8);
|
|
|
|
/* Coefficient voodoo from the HP03 datasheet. */
|
|
if (d2_val >= cx_val[4])
|
|
ab_val = coefs[14]; /* A-value */
|
|
else
|
|
ab_val = coefs[15]; /* B-value */
|
|
|
|
diff_val = d2_val - cx_val[4];
|
|
dut = (ab_val * (diff_val >> 7) * (diff_val >> 7)) >> coefs[16];
|
|
dut = diff_val - dut;
|
|
|
|
off = (cx_val[1] + (((cx_val[3] - 1024) * dut) >> 14)) * 4;
|
|
sens = cx_val[0] + ((cx_val[2] * dut) >> 10);
|
|
x = ((sens * (d1_val - 7168)) >> 14) - off;
|
|
|
|
priv->pressure = ((x * 100) >> 5) + (cx_val[6] * 10);
|
|
priv->temp = 250 + ((dut * cx_val[5]) >> 16) - (dut >> coefs[17]);
|
|
|
|
return 0;
|
|
|
|
err_adc:
|
|
gpiod_set_value_cansleep(priv->xclr_gpio, 0);
|
|
return ret;
|
|
}
|
|
|
|
static int hp03_read_raw(struct iio_dev *indio_dev,
|
|
struct iio_chan_spec const *chan,
|
|
int *val, int *val2, long mask)
|
|
{
|
|
struct hp03_priv *priv = iio_priv(indio_dev);
|
|
int ret;
|
|
|
|
mutex_lock(&priv->lock);
|
|
ret = hp03_update_temp_pressure(priv);
|
|
mutex_unlock(&priv->lock);
|
|
|
|
if (ret)
|
|
return ret;
|
|
|
|
switch (mask) {
|
|
case IIO_CHAN_INFO_RAW:
|
|
switch (chan->type) {
|
|
case IIO_PRESSURE:
|
|
*val = priv->pressure;
|
|
return IIO_VAL_INT;
|
|
case IIO_TEMP:
|
|
*val = priv->temp;
|
|
return IIO_VAL_INT;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
break;
|
|
case IIO_CHAN_INFO_SCALE:
|
|
switch (chan->type) {
|
|
case IIO_PRESSURE:
|
|
*val = 0;
|
|
*val2 = 1000;
|
|
return IIO_VAL_INT_PLUS_MICRO;
|
|
case IIO_TEMP:
|
|
*val = 10;
|
|
return IIO_VAL_INT;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
static const struct iio_info hp03_info = {
|
|
.read_raw = &hp03_read_raw,
|
|
};
|
|
|
|
static int hp03_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
struct device *dev = &client->dev;
|
|
struct iio_dev *indio_dev;
|
|
struct hp03_priv *priv;
|
|
int ret;
|
|
|
|
indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
|
|
if (!indio_dev)
|
|
return -ENOMEM;
|
|
|
|
priv = iio_priv(indio_dev);
|
|
priv->client = client;
|
|
mutex_init(&priv->lock);
|
|
|
|
indio_dev->dev.parent = dev;
|
|
indio_dev->name = id->name;
|
|
indio_dev->channels = hp03_channels;
|
|
indio_dev->num_channels = ARRAY_SIZE(hp03_channels);
|
|
indio_dev->info = &hp03_info;
|
|
indio_dev->modes = INDIO_DIRECT_MODE;
|
|
|
|
priv->xclr_gpio = devm_gpiod_get_index(dev, "xclr", 0, GPIOD_OUT_HIGH);
|
|
if (IS_ERR(priv->xclr_gpio)) {
|
|
dev_err(dev, "Failed to claim XCLR GPIO\n");
|
|
ret = PTR_ERR(priv->xclr_gpio);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Allocate another device for the on-sensor EEPROM,
|
|
* which has it's dedicated I2C address and contains
|
|
* the calibration constants for the sensor.
|
|
*/
|
|
priv->eeprom_client = i2c_new_dummy(client->adapter, HP03_EEPROM_ADDR);
|
|
if (!priv->eeprom_client) {
|
|
dev_err(dev, "New EEPROM I2C device failed\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
priv->eeprom_regmap = regmap_init_i2c(priv->eeprom_client,
|
|
&hp03_regmap_config);
|
|
if (IS_ERR(priv->eeprom_regmap)) {
|
|
dev_err(dev, "Failed to allocate EEPROM regmap\n");
|
|
ret = PTR_ERR(priv->eeprom_regmap);
|
|
goto err_cleanup_eeprom_client;
|
|
}
|
|
|
|
ret = iio_device_register(indio_dev);
|
|
if (ret) {
|
|
dev_err(dev, "Failed to register IIO device\n");
|
|
goto err_cleanup_eeprom_regmap;
|
|
}
|
|
|
|
i2c_set_clientdata(client, indio_dev);
|
|
|
|
return 0;
|
|
|
|
err_cleanup_eeprom_regmap:
|
|
regmap_exit(priv->eeprom_regmap);
|
|
|
|
err_cleanup_eeprom_client:
|
|
i2c_unregister_device(priv->eeprom_client);
|
|
return ret;
|
|
}
|
|
|
|
static int hp03_remove(struct i2c_client *client)
|
|
{
|
|
struct iio_dev *indio_dev = i2c_get_clientdata(client);
|
|
struct hp03_priv *priv = iio_priv(indio_dev);
|
|
|
|
iio_device_unregister(indio_dev);
|
|
regmap_exit(priv->eeprom_regmap);
|
|
i2c_unregister_device(priv->eeprom_client);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct i2c_device_id hp03_id[] = {
|
|
{ "hp03", 0 },
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, hp03_id);
|
|
|
|
static const struct of_device_id hp03_of_match[] = {
|
|
{ .compatible = "hoperf,hp03" },
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(of, hp03_of_match);
|
|
|
|
static struct i2c_driver hp03_driver = {
|
|
.driver = {
|
|
.name = "hp03",
|
|
.of_match_table = hp03_of_match,
|
|
},
|
|
.probe = hp03_probe,
|
|
.remove = hp03_remove,
|
|
.id_table = hp03_id,
|
|
};
|
|
module_i2c_driver(hp03_driver);
|
|
|
|
MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
|
|
MODULE_DESCRIPTION("Driver for Hope RF HP03 pressure and temperature sensor");
|
|
MODULE_LICENSE("GPL v2");
|