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|
/*
* STMicroelectronics hts221 sensor driver
*
* Copyright 2016 STMicroelectronics Inc.
*
* Lorenzo Bianconi <lorenzo.bianconi@st.com>
*
* Licensed under the GPL-2.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/iio/sysfs.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <asm/unaligned.h>
#include <linux/regmap.h>
#include <linux/bitfield.h>
#include "hts221.h"
#define HTS221_REG_WHOAMI_ADDR 0x0f
#define HTS221_REG_WHOAMI_VAL 0xbc
#define HTS221_REG_CNTRL1_ADDR 0x20
#define HTS221_REG_CNTRL2_ADDR 0x21
#define HTS221_REG_AVG_ADDR 0x10
#define HTS221_REG_H_OUT_L 0x28
#define HTS221_REG_T_OUT_L 0x2a
#define HTS221_HUMIDITY_AVG_MASK 0x07
#define HTS221_TEMP_AVG_MASK 0x38
#define HTS221_ODR_MASK 0x03
#define HTS221_BDU_MASK BIT(2)
#define HTS221_ENABLE_MASK BIT(7)
/* calibration registers */
#define HTS221_REG_0RH_CAL_X_H 0x36
#define HTS221_REG_1RH_CAL_X_H 0x3a
#define HTS221_REG_0RH_CAL_Y_H 0x30
#define HTS221_REG_1RH_CAL_Y_H 0x31
#define HTS221_REG_0T_CAL_X_L 0x3c
#define HTS221_REG_1T_CAL_X_L 0x3e
#define HTS221_REG_0T_CAL_Y_H 0x32
#define HTS221_REG_1T_CAL_Y_H 0x33
#define HTS221_REG_T1_T0_CAL_Y_H 0x35
struct hts221_odr {
u8 hz;
u8 val;
};
#define HTS221_AVG_DEPTH 8
struct hts221_avg {
u8 addr;
u8 mask;
u16 avg_avl[HTS221_AVG_DEPTH];
};
static const struct hts221_odr hts221_odr_table[] = {
{ 1, 0x01 }, /* 1Hz */
{ 7, 0x02 }, /* 7Hz */
{ 13, 0x03 }, /* 12.5Hz */
};
static const struct hts221_avg hts221_avg_list[] = {
{
.addr = HTS221_REG_AVG_ADDR,
.mask = HTS221_HUMIDITY_AVG_MASK,
.avg_avl = {
4, /* 0.4 %RH */
8, /* 0.3 %RH */
16, /* 0.2 %RH */
32, /* 0.15 %RH */
64, /* 0.1 %RH */
128, /* 0.07 %RH */
256, /* 0.05 %RH */
512, /* 0.03 %RH */
},
},
{
.addr = HTS221_REG_AVG_ADDR,
.mask = HTS221_TEMP_AVG_MASK,
.avg_avl = {
2, /* 0.08 degC */
4, /* 0.05 degC */
8, /* 0.04 degC */
16, /* 0.03 degC */
32, /* 0.02 degC */
64, /* 0.015 degC */
128, /* 0.01 degC */
256, /* 0.007 degC */
},
},
};
static const struct iio_chan_spec hts221_channels[] = {
{
.type = IIO_HUMIDITYRELATIVE,
.address = HTS221_REG_H_OUT_L,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_OFFSET) |
BIT(IIO_CHAN_INFO_SCALE) |
BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
.scan_index = 0,
.scan_type = {
.sign = 's',
.realbits = 16,
.storagebits = 16,
.endianness = IIO_LE,
},
},
{
.type = IIO_TEMP,
.address = HTS221_REG_T_OUT_L,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_OFFSET) |
BIT(IIO_CHAN_INFO_SCALE) |
BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
.scan_index = 1,
.scan_type = {
.sign = 's',
.realbits = 16,
.storagebits = 16,
.endianness = IIO_LE,
},
},
IIO_CHAN_SOFT_TIMESTAMP(2),
};
static int hts221_check_whoami(struct hts221_hw *hw)
{
int err, data;
err = regmap_read(hw->regmap, HTS221_REG_WHOAMI_ADDR, &data);
if (err < 0) {
dev_err(hw->dev, "failed to read whoami register\n");
return err;
}
if (data != HTS221_REG_WHOAMI_VAL) {
dev_err(hw->dev, "wrong whoami {%02x vs %02x}\n",
data, HTS221_REG_WHOAMI_VAL);
return -ENODEV;
}
return 0;
}
static int hts221_update_odr(struct hts221_hw *hw, u8 odr)
{
int i, err;
for (i = 0; i < ARRAY_SIZE(hts221_odr_table); i++)
if (hts221_odr_table[i].hz == odr)
break;
if (i == ARRAY_SIZE(hts221_odr_table))
return -EINVAL;
err = regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
HTS221_ODR_MASK,
FIELD_PREP(HTS221_ODR_MASK,
hts221_odr_table[i].val));
if (err < 0)
return err;
hw->odr = odr;
return 0;
}
static int hts221_update_avg(struct hts221_hw *hw,
enum hts221_sensor_type type,
u16 val)
{
const struct hts221_avg *avg = &hts221_avg_list[type];
int i, err, data;
for (i = 0; i < HTS221_AVG_DEPTH; i++)
if (avg->avg_avl[i] == val)
break;
if (i == HTS221_AVG_DEPTH)
return -EINVAL;
data = ((i << __ffs(avg->mask)) & avg->mask);
err = regmap_update_bits(hw->regmap, avg->addr,
avg->mask, data);
if (err < 0)
return err;
hw->sensors[type].cur_avg_idx = i;
return 0;
}
static ssize_t hts221_sysfs_sampling_freq(struct device *dev,
struct device_attribute *attr,
char *buf)
{
int i;
ssize_t len = 0;
for (i = 0; i < ARRAY_SIZE(hts221_odr_table); i++)
len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
hts221_odr_table[i].hz);
buf[len - 1] = '\n';
return len;
}
static ssize_t
hts221_sysfs_rh_oversampling_avail(struct device *dev,
struct device_attribute *attr,
char *buf)
{
const struct hts221_avg *avg = &hts221_avg_list[HTS221_SENSOR_H];
ssize_t len = 0;
int i;
for (i = 0; i < ARRAY_SIZE(avg->avg_avl); i++)
len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
avg->avg_avl[i]);
buf[len - 1] = '\n';
return len;
}
static ssize_t
hts221_sysfs_temp_oversampling_avail(struct device *dev,
struct device_attribute *attr,
char *buf)
{
const struct hts221_avg *avg = &hts221_avg_list[HTS221_SENSOR_T];
ssize_t len = 0;
int i;
for (i = 0; i < ARRAY_SIZE(avg->avg_avl); i++)
len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
avg->avg_avl[i]);
buf[len - 1] = '\n';
return len;
}
int hts221_set_enable(struct hts221_hw *hw, bool enable)
{
int err;
err = regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
HTS221_ENABLE_MASK,
FIELD_PREP(HTS221_ENABLE_MASK, enable));
if (err < 0)
return err;
hw->enabled = enable;
return 0;
}
static int hts221_parse_temp_caldata(struct hts221_hw *hw)
{
int err, *slope, *b_gen, cal0, cal1;
s16 cal_x0, cal_x1, cal_y0, cal_y1;
__le16 val;
err = regmap_read(hw->regmap, HTS221_REG_0T_CAL_Y_H, &cal0);
if (err < 0)
return err;
err = regmap_read(hw->regmap, HTS221_REG_T1_T0_CAL_Y_H, &cal1);
if (err < 0)
return err;
cal_y0 = ((cal1 & 0x3) << 8) | cal0;
err = regmap_read(hw->regmap, HTS221_REG_1T_CAL_Y_H, &cal0);
if (err < 0)
return err;
cal_y1 = (((cal1 & 0xc) >> 2) << 8) | cal0;
err = regmap_bulk_read(hw->regmap, HTS221_REG_0T_CAL_X_L,
&val, sizeof(val));
if (err < 0)
return err;
cal_x0 = le16_to_cpu(val);
err = regmap_bulk_read(hw->regmap, HTS221_REG_1T_CAL_X_L,
&val, sizeof(val));
if (err < 0)
return err;
cal_x1 = le16_to_cpu(val);
slope = &hw->sensors[HTS221_SENSOR_T].slope;
b_gen = &hw->sensors[HTS221_SENSOR_T].b_gen;
*slope = ((cal_y1 - cal_y0) * 8000) / (cal_x1 - cal_x0);
*b_gen = (((s32)cal_x1 * cal_y0 - (s32)cal_x0 * cal_y1) * 1000) /
(cal_x1 - cal_x0);
*b_gen *= 8;
return 0;
}
static int hts221_parse_rh_caldata(struct hts221_hw *hw)
{
int err, *slope, *b_gen, data;
s16 cal_x0, cal_x1, cal_y0, cal_y1;
__le16 val;
err = regmap_read(hw->regmap, HTS221_REG_0RH_CAL_Y_H, &data);
if (err < 0)
return err;
cal_y0 = data;
err = regmap_read(hw->regmap, HTS221_REG_1RH_CAL_Y_H, &data);
if (err < 0)
return err;
cal_y1 = data;
err = regmap_bulk_read(hw->regmap, HTS221_REG_0RH_CAL_X_H,
&val, sizeof(val));
if (err < 0)
return err;
cal_x0 = le16_to_cpu(val);
err = regmap_bulk_read(hw->regmap, HTS221_REG_1RH_CAL_X_H,
&val, sizeof(val));
if (err < 0)
return err;
cal_x1 = le16_to_cpu(val);
slope = &hw->sensors[HTS221_SENSOR_H].slope;
b_gen = &hw->sensors[HTS221_SENSOR_H].b_gen;
*slope = ((cal_y1 - cal_y0) * 8000) / (cal_x1 - cal_x0);
*b_gen = (((s32)cal_x1 * cal_y0 - (s32)cal_x0 * cal_y1) * 1000) /
(cal_x1 - cal_x0);
*b_gen *= 8;
return 0;
}
static int hts221_get_sensor_scale(struct hts221_hw *hw,
enum iio_chan_type ch_type,
int *val, int *val2)
{
s64 tmp;
s32 rem, div, data;
switch (ch_type) {
case IIO_HUMIDITYRELATIVE:
data = hw->sensors[HTS221_SENSOR_H].slope;
div = (1 << 4) * 1000;
break;
case IIO_TEMP:
data = hw->sensors[HTS221_SENSOR_T].slope;
div = (1 << 6) * 1000;
break;
default:
return -EINVAL;
}
tmp = div_s64(data * 1000000000LL, div);
tmp = div_s64_rem(tmp, 1000000000LL, &rem);
*val = tmp;
*val2 = rem;
return IIO_VAL_INT_PLUS_NANO;
}
static int hts221_get_sensor_offset(struct hts221_hw *hw,
enum iio_chan_type ch_type,
int *val, int *val2)
{
s64 tmp;
s32 rem, div, data;
switch (ch_type) {
case IIO_HUMIDITYRELATIVE:
data = hw->sensors[HTS221_SENSOR_H].b_gen;
div = hw->sensors[HTS221_SENSOR_H].slope;
break;
case IIO_TEMP:
data = hw->sensors[HTS221_SENSOR_T].b_gen;
div = hw->sensors[HTS221_SENSOR_T].slope;
break;
default:
return -EINVAL;
}
tmp = div_s64(data * 1000000000LL, div);
tmp = div_s64_rem(tmp, 1000000000LL, &rem);
*val = tmp;
*val2 = rem;
return IIO_VAL_INT_PLUS_NANO;
}
static int hts221_read_oneshot(struct hts221_hw *hw, u8 addr, int *val)
{
u8 data[HTS221_DATA_SIZE];
int err;
err = hts221_set_enable(hw, true);
if (err < 0)
return err;
msleep(50);
err = regmap_bulk_read(hw->regmap, addr, data, sizeof(data));
if (err < 0)
return err;
hts221_set_enable(hw, false);
*val = (s16)get_unaligned_le16(data);
return IIO_VAL_INT;
}
static int hts221_read_raw(struct iio_dev *iio_dev,
struct iio_chan_spec const *ch,
int *val, int *val2, long mask)
{
struct hts221_hw *hw = iio_priv(iio_dev);
int ret;
ret = iio_device_claim_direct_mode(iio_dev);
if (ret)
return ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = hts221_read_oneshot(hw, ch->address, val);
break;
case IIO_CHAN_INFO_SCALE:
ret = hts221_get_sensor_scale(hw, ch->type, val, val2);
break;
case IIO_CHAN_INFO_OFFSET:
ret = hts221_get_sensor_offset(hw, ch->type, val, val2);
break;
case IIO_CHAN_INFO_SAMP_FREQ:
*val = hw->odr;
ret = IIO_VAL_INT;
break;
case IIO_CHAN_INFO_OVERSAMPLING_RATIO: {
u8 idx;
const struct hts221_avg *avg;
switch (ch->type) {
case IIO_HUMIDITYRELATIVE:
avg = &hts221_avg_list[HTS221_SENSOR_H];
idx = hw->sensors[HTS221_SENSOR_H].cur_avg_idx;
*val = avg->avg_avl[idx];
ret = IIO_VAL_INT;
break;
case IIO_TEMP:
avg = &hts221_avg_list[HTS221_SENSOR_T];
idx = hw->sensors[HTS221_SENSOR_T].cur_avg_idx;
*val = avg->avg_avl[idx];
ret = IIO_VAL_INT;
break;
default:
ret = -EINVAL;
break;
}
break;
}
default:
ret = -EINVAL;
break;
}
iio_device_release_direct_mode(iio_dev);
return ret;
}
static int hts221_write_raw(struct iio_dev *iio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct hts221_hw *hw = iio_priv(iio_dev);
int ret;
ret = iio_device_claim_direct_mode(iio_dev);
if (ret)
return ret;
switch (mask) {
case IIO_CHAN_INFO_SAMP_FREQ:
ret = hts221_update_odr(hw, val);
break;
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
switch (chan->type) {
case IIO_HUMIDITYRELATIVE:
ret = hts221_update_avg(hw, HTS221_SENSOR_H, val);
break;
case IIO_TEMP:
ret = hts221_update_avg(hw, HTS221_SENSOR_T, val);
break;
default:
ret = -EINVAL;
break;
}
break;
default:
ret = -EINVAL;
break;
}
iio_device_release_direct_mode(iio_dev);
return ret;
}
static int hts221_validate_trigger(struct iio_dev *iio_dev,
struct iio_trigger *trig)
{
struct hts221_hw *hw = iio_priv(iio_dev);
return hw->trig == trig ? 0 : -EINVAL;
}
static IIO_DEVICE_ATTR(in_humidity_oversampling_ratio_available, S_IRUGO,
hts221_sysfs_rh_oversampling_avail, NULL, 0);
static IIO_DEVICE_ATTR(in_temp_oversampling_ratio_available, S_IRUGO,
hts221_sysfs_temp_oversampling_avail, NULL, 0);
static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(hts221_sysfs_sampling_freq);
static struct attribute *hts221_attributes[] = {
&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
&iio_dev_attr_in_humidity_oversampling_ratio_available.dev_attr.attr,
&iio_dev_attr_in_temp_oversampling_ratio_available.dev_attr.attr,
NULL,
};
static const struct attribute_group hts221_attribute_group = {
.attrs = hts221_attributes,
};
static const struct iio_info hts221_info = {
.attrs = &hts221_attribute_group,
.read_raw = hts221_read_raw,
.write_raw = hts221_write_raw,
.validate_trigger = hts221_validate_trigger,
};
static const unsigned long hts221_scan_masks[] = {0x3, 0x0};
int hts221_probe(struct device *dev, int irq, const char *name,
struct regmap *regmap)
{
struct iio_dev *iio_dev;
struct hts221_hw *hw;
int err;
u8 data;
iio_dev = devm_iio_device_alloc(dev, sizeof(*hw));
if (!iio_dev)
return -ENOMEM;
dev_set_drvdata(dev, (void *)iio_dev);
hw = iio_priv(iio_dev);
hw->name = name;
hw->dev = dev;
hw->irq = irq;
hw->regmap = regmap;
err = hts221_check_whoami(hw);
if (err < 0)
return err;
iio_dev->modes = INDIO_DIRECT_MODE;
iio_dev->dev.parent = hw->dev;
iio_dev->available_scan_masks = hts221_scan_masks;
iio_dev->channels = hts221_channels;
iio_dev->num_channels = ARRAY_SIZE(hts221_channels);
iio_dev->name = HTS221_DEV_NAME;
iio_dev->info = &hts221_info;
/* enable Block Data Update */
err = regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
HTS221_BDU_MASK,
FIELD_PREP(HTS221_BDU_MASK, 1));
if (err < 0)
return err;
err = hts221_update_odr(hw, hts221_odr_table[0].hz);
if (err < 0)
return err;
/* configure humidity sensor */
err = hts221_parse_rh_caldata(hw);
if (err < 0) {
dev_err(hw->dev, "failed to get rh calibration data\n");
return err;
}
data = hts221_avg_list[HTS221_SENSOR_H].avg_avl[3];
err = hts221_update_avg(hw, HTS221_SENSOR_H, data);
if (err < 0) {
dev_err(hw->dev, "failed to set rh oversampling ratio\n");
return err;
}
/* configure temperature sensor */
err = hts221_parse_temp_caldata(hw);
if (err < 0) {
dev_err(hw->dev,
"failed to get temperature calibration data\n");
return err;
}
data = hts221_avg_list[HTS221_SENSOR_T].avg_avl[3];
err = hts221_update_avg(hw, HTS221_SENSOR_T, data);
if (err < 0) {
dev_err(hw->dev,
"failed to set temperature oversampling ratio\n");
return err;
}
if (hw->irq > 0) {
err = hts221_allocate_buffers(hw);
if (err < 0)
return err;
err = hts221_allocate_trigger(hw);
if (err)
return err;
}
return devm_iio_device_register(hw->dev, iio_dev);
}
EXPORT_SYMBOL(hts221_probe);
static int __maybe_unused hts221_suspend(struct device *dev)
{
struct iio_dev *iio_dev = dev_get_drvdata(dev);
struct hts221_hw *hw = iio_priv(iio_dev);
return regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
HTS221_ENABLE_MASK,
FIELD_PREP(HTS221_ENABLE_MASK, false));
}
static int __maybe_unused hts221_resume(struct device *dev)
{
struct iio_dev *iio_dev = dev_get_drvdata(dev);
struct hts221_hw *hw = iio_priv(iio_dev);
int err = 0;
if (hw->enabled)
err = regmap_update_bits(hw->regmap, HTS221_REG_CNTRL1_ADDR,
HTS221_ENABLE_MASK,
FIELD_PREP(HTS221_ENABLE_MASK,
true));
return err;
}
const struct dev_pm_ops hts221_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(hts221_suspend, hts221_resume)
};
EXPORT_SYMBOL(hts221_pm_ops);
MODULE_AUTHOR("Lorenzo Bianconi <lorenzo.bianconi@st.com>");
MODULE_DESCRIPTION("STMicroelectronics hts221 sensor driver");
MODULE_LICENSE("GPL v2");
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