// SPDX-License-Identifier: GPL-2.0
|
/*
|
* AD7746 capacitive sensor driver supporting AD7745, AD7746 and AD7747
|
*
|
* Copyright 2011 Analog Devices Inc.
|
*/
|
|
#include <linux/delay.h>
|
#include <linux/device.h>
|
#include <linux/i2c.h>
|
#include <linux/interrupt.h>
|
#include <linux/kernel.h>
|
#include <linux/module.h>
|
#include <linux/slab.h>
|
#include <linux/stat.h>
|
#include <linux/sysfs.h>
|
|
#include <linux/iio/iio.h>
|
#include <linux/iio/sysfs.h>
|
|
#include "ad7746.h"
|
|
/*
|
* AD7746 Register Definition
|
*/
|
|
#define AD7746_REG_STATUS 0
|
#define AD7746_REG_CAP_DATA_HIGH 1
|
#define AD7746_REG_VT_DATA_HIGH 4
|
#define AD7746_REG_CAP_SETUP 7
|
#define AD7746_REG_VT_SETUP 8
|
#define AD7746_REG_EXC_SETUP 9
|
#define AD7746_REG_CFG 10
|
#define AD7746_REG_CAPDACA 11
|
#define AD7746_REG_CAPDACB 12
|
#define AD7746_REG_CAP_OFFH 13
|
#define AD7746_REG_CAP_GAINH 15
|
#define AD7746_REG_VOLT_GAINH 17
|
|
/* Status Register Bit Designations (AD7746_REG_STATUS) */
|
#define AD7746_STATUS_EXCERR BIT(3)
|
#define AD7746_STATUS_RDY BIT(2)
|
#define AD7746_STATUS_RDYVT BIT(1)
|
#define AD7746_STATUS_RDYCAP BIT(0)
|
|
/* Capacitive Channel Setup Register Bit Designations (AD7746_REG_CAP_SETUP) */
|
#define AD7746_CAPSETUP_CAPEN BIT(7)
|
#define AD7746_CAPSETUP_CIN2 BIT(6) /* AD7746 only */
|
#define AD7746_CAPSETUP_CAPDIFF BIT(5)
|
#define AD7746_CAPSETUP_CACHOP BIT(0)
|
|
/* Voltage/Temperature Setup Register Bit Designations (AD7746_REG_VT_SETUP) */
|
#define AD7746_VTSETUP_VTEN (1 << 7)
|
#define AD7746_VTSETUP_VTMD_INT_TEMP (0 << 5)
|
#define AD7746_VTSETUP_VTMD_EXT_TEMP (1 << 5)
|
#define AD7746_VTSETUP_VTMD_VDD_MON (2 << 5)
|
#define AD7746_VTSETUP_VTMD_EXT_VIN (3 << 5)
|
#define AD7746_VTSETUP_EXTREF BIT(4)
|
#define AD7746_VTSETUP_VTSHORT BIT(1)
|
#define AD7746_VTSETUP_VTCHOP BIT(0)
|
|
/* Excitation Setup Register Bit Designations (AD7746_REG_EXC_SETUP) */
|
#define AD7746_EXCSETUP_CLKCTRL BIT(7)
|
#define AD7746_EXCSETUP_EXCON BIT(6)
|
#define AD7746_EXCSETUP_EXCB BIT(5)
|
#define AD7746_EXCSETUP_NEXCB BIT(4)
|
#define AD7746_EXCSETUP_EXCA BIT(3)
|
#define AD7746_EXCSETUP_NEXCA BIT(2)
|
#define AD7746_EXCSETUP_EXCLVL(x) (((x) & 0x3) << 0)
|
|
/* Config Register Bit Designations (AD7746_REG_CFG) */
|
#define AD7746_CONF_VTFS_SHIFT 6
|
#define AD7746_CONF_CAPFS_SHIFT 3
|
#define AD7746_CONF_VTFS_MASK GENMASK(7, 6)
|
#define AD7746_CONF_CAPFS_MASK GENMASK(5, 3)
|
#define AD7746_CONF_MODE_IDLE (0 << 0)
|
#define AD7746_CONF_MODE_CONT_CONV (1 << 0)
|
#define AD7746_CONF_MODE_SINGLE_CONV (2 << 0)
|
#define AD7746_CONF_MODE_PWRDN (3 << 0)
|
#define AD7746_CONF_MODE_OFFS_CAL (5 << 0)
|
#define AD7746_CONF_MODE_GAIN_CAL (6 << 0)
|
|
/* CAPDAC Register Bit Designations (AD7746_REG_CAPDACx) */
|
#define AD7746_CAPDAC_DACEN BIT(7)
|
#define AD7746_CAPDAC_DACP(x) ((x) & 0x7F)
|
|
/*
|
* struct ad7746_chip_info - chip specific information
|
*/
|
|
struct ad7746_chip_info {
|
struct i2c_client *client;
|
struct mutex lock; /* protect sensor state */
|
/*
|
* Capacitive channel digital filter setup;
|
* conversion time/update rate setup per channel
|
*/
|
u8 config;
|
u8 cap_setup;
|
u8 vt_setup;
|
u8 capdac[2][2];
|
s8 capdac_set;
|
|
union {
|
__be32 d32;
|
u8 d8[4];
|
} data ____cacheline_aligned;
|
};
|
|
enum ad7746_chan {
|
VIN,
|
VIN_VDD,
|
TEMP_INT,
|
TEMP_EXT,
|
CIN1,
|
CIN1_DIFF,
|
CIN2,
|
CIN2_DIFF,
|
};
|
|
static const struct iio_chan_spec ad7746_channels[] = {
|
[VIN] = {
|
.type = IIO_VOLTAGE,
|
.indexed = 1,
|
.channel = 0,
|
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
|
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |
|
BIT(IIO_CHAN_INFO_SAMP_FREQ),
|
.address = AD7746_REG_VT_DATA_HIGH << 8 |
|
AD7746_VTSETUP_VTMD_EXT_VIN,
|
},
|
[VIN_VDD] = {
|
.type = IIO_VOLTAGE,
|
.indexed = 1,
|
.channel = 1,
|
.extend_name = "supply",
|
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
|
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |
|
BIT(IIO_CHAN_INFO_SAMP_FREQ),
|
.address = AD7746_REG_VT_DATA_HIGH << 8 |
|
AD7746_VTSETUP_VTMD_VDD_MON,
|
},
|
[TEMP_INT] = {
|
.type = IIO_TEMP,
|
.indexed = 1,
|
.channel = 0,
|
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
|
.address = AD7746_REG_VT_DATA_HIGH << 8 |
|
AD7746_VTSETUP_VTMD_INT_TEMP,
|
},
|
[TEMP_EXT] = {
|
.type = IIO_TEMP,
|
.indexed = 1,
|
.channel = 1,
|
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
|
.address = AD7746_REG_VT_DATA_HIGH << 8 |
|
AD7746_VTSETUP_VTMD_EXT_TEMP,
|
},
|
[CIN1] = {
|
.type = IIO_CAPACITANCE,
|
.indexed = 1,
|
.channel = 0,
|
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
|
BIT(IIO_CHAN_INFO_CALIBSCALE) | BIT(IIO_CHAN_INFO_OFFSET),
|
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBBIAS) |
|
BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_SAMP_FREQ),
|
.address = AD7746_REG_CAP_DATA_HIGH << 8,
|
},
|
[CIN1_DIFF] = {
|
.type = IIO_CAPACITANCE,
|
.differential = 1,
|
.indexed = 1,
|
.channel = 0,
|
.channel2 = 2,
|
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
|
BIT(IIO_CHAN_INFO_CALIBSCALE) | BIT(IIO_CHAN_INFO_OFFSET),
|
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBBIAS) |
|
BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_SAMP_FREQ),
|
.address = AD7746_REG_CAP_DATA_HIGH << 8 |
|
AD7746_CAPSETUP_CAPDIFF
|
},
|
[CIN2] = {
|
.type = IIO_CAPACITANCE,
|
.indexed = 1,
|
.channel = 1,
|
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
|
BIT(IIO_CHAN_INFO_CALIBSCALE) | BIT(IIO_CHAN_INFO_OFFSET),
|
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBBIAS) |
|
BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_SAMP_FREQ),
|
.address = AD7746_REG_CAP_DATA_HIGH << 8 |
|
AD7746_CAPSETUP_CIN2,
|
},
|
[CIN2_DIFF] = {
|
.type = IIO_CAPACITANCE,
|
.differential = 1,
|
.indexed = 1,
|
.channel = 1,
|
.channel2 = 3,
|
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
|
BIT(IIO_CHAN_INFO_CALIBSCALE) | BIT(IIO_CHAN_INFO_OFFSET),
|
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBBIAS) |
|
BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_SAMP_FREQ),
|
.address = AD7746_REG_CAP_DATA_HIGH << 8 |
|
AD7746_CAPSETUP_CAPDIFF | AD7746_CAPSETUP_CIN2,
|
}
|
};
|
|
/* Values are Update Rate (Hz), Conversion Time (ms) + 1*/
|
static const unsigned char ad7746_vt_filter_rate_table[][2] = {
|
{50, 20 + 1}, {31, 32 + 1}, {16, 62 + 1}, {8, 122 + 1},
|
};
|
|
static const unsigned char ad7746_cap_filter_rate_table[][2] = {
|
{91, 11 + 1}, {84, 12 + 1}, {50, 20 + 1}, {26, 38 + 1},
|
{16, 62 + 1}, {13, 77 + 1}, {11, 92 + 1}, {9, 110 + 1},
|
};
|
|
static int ad7746_select_channel(struct iio_dev *indio_dev,
|
struct iio_chan_spec const *chan)
|
{
|
struct ad7746_chip_info *chip = iio_priv(indio_dev);
|
u8 vt_setup, cap_setup;
|
int ret, delay, idx;
|
|
switch (chan->type) {
|
case IIO_CAPACITANCE:
|
cap_setup = (chan->address & 0xFF) | AD7746_CAPSETUP_CAPEN;
|
vt_setup = chip->vt_setup & ~AD7746_VTSETUP_VTEN;
|
idx = (chip->config & AD7746_CONF_CAPFS_MASK) >>
|
AD7746_CONF_CAPFS_SHIFT;
|
delay = ad7746_cap_filter_rate_table[idx][1];
|
|
if (chip->capdac_set != chan->channel) {
|
ret = i2c_smbus_write_byte_data(chip->client,
|
AD7746_REG_CAPDACA,
|
chip->capdac[chan->channel][0]);
|
if (ret < 0)
|
return ret;
|
ret = i2c_smbus_write_byte_data(chip->client,
|
AD7746_REG_CAPDACB,
|
chip->capdac[chan->channel][1]);
|
if (ret < 0)
|
return ret;
|
|
chip->capdac_set = chan->channel;
|
}
|
break;
|
case IIO_VOLTAGE:
|
case IIO_TEMP:
|
vt_setup = (chan->address & 0xFF) | AD7746_VTSETUP_VTEN;
|
cap_setup = chip->cap_setup & ~AD7746_CAPSETUP_CAPEN;
|
idx = (chip->config & AD7746_CONF_VTFS_MASK) >>
|
AD7746_CONF_VTFS_SHIFT;
|
delay = ad7746_cap_filter_rate_table[idx][1];
|
break;
|
default:
|
return -EINVAL;
|
}
|
|
if (chip->cap_setup != cap_setup) {
|
ret = i2c_smbus_write_byte_data(chip->client,
|
AD7746_REG_CAP_SETUP,
|
cap_setup);
|
if (ret < 0)
|
return ret;
|
|
chip->cap_setup = cap_setup;
|
}
|
|
if (chip->vt_setup != vt_setup) {
|
ret = i2c_smbus_write_byte_data(chip->client,
|
AD7746_REG_VT_SETUP,
|
vt_setup);
|
if (ret < 0)
|
return ret;
|
|
chip->vt_setup = vt_setup;
|
}
|
|
return delay;
|
}
|
|
static inline ssize_t ad7746_start_calib(struct device *dev,
|
struct device_attribute *attr,
|
const char *buf,
|
size_t len,
|
u8 regval)
|
{
|
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
|
struct ad7746_chip_info *chip = iio_priv(indio_dev);
|
int ret, timeout = 10;
|
bool doit;
|
|
ret = strtobool(buf, &doit);
|
if (ret < 0)
|
return ret;
|
|
if (!doit)
|
return 0;
|
|
mutex_lock(&chip->lock);
|
regval |= chip->config;
|
ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_CFG, regval);
|
if (ret < 0)
|
goto unlock;
|
|
do {
|
msleep(20);
|
ret = i2c_smbus_read_byte_data(chip->client, AD7746_REG_CFG);
|
if (ret < 0)
|
goto unlock;
|
|
} while ((ret == regval) && timeout--);
|
|
mutex_unlock(&chip->lock);
|
|
return len;
|
|
unlock:
|
mutex_unlock(&chip->lock);
|
return ret;
|
}
|
|
static ssize_t ad7746_start_offset_calib(struct device *dev,
|
struct device_attribute *attr,
|
const char *buf,
|
size_t len)
|
{
|
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
|
int ret = ad7746_select_channel(indio_dev,
|
&ad7746_channels[to_iio_dev_attr(attr)->address]);
|
if (ret < 0)
|
return ret;
|
|
return ad7746_start_calib(dev, attr, buf, len,
|
AD7746_CONF_MODE_OFFS_CAL);
|
}
|
|
static ssize_t ad7746_start_gain_calib(struct device *dev,
|
struct device_attribute *attr,
|
const char *buf,
|
size_t len)
|
{
|
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
|
int ret = ad7746_select_channel(indio_dev,
|
&ad7746_channels[to_iio_dev_attr(attr)->address]);
|
if (ret < 0)
|
return ret;
|
|
return ad7746_start_calib(dev, attr, buf, len,
|
AD7746_CONF_MODE_GAIN_CAL);
|
}
|
|
static IIO_DEVICE_ATTR(in_capacitance0_calibbias_calibration,
|
0200, NULL, ad7746_start_offset_calib, CIN1);
|
static IIO_DEVICE_ATTR(in_capacitance1_calibbias_calibration,
|
0200, NULL, ad7746_start_offset_calib, CIN2);
|
static IIO_DEVICE_ATTR(in_capacitance0_calibscale_calibration,
|
0200, NULL, ad7746_start_gain_calib, CIN1);
|
static IIO_DEVICE_ATTR(in_capacitance1_calibscale_calibration,
|
0200, NULL, ad7746_start_gain_calib, CIN2);
|
static IIO_DEVICE_ATTR(in_voltage0_calibscale_calibration,
|
0200, NULL, ad7746_start_gain_calib, VIN);
|
|
static int ad7746_store_cap_filter_rate_setup(struct ad7746_chip_info *chip,
|
int val)
|
{
|
int i;
|
|
for (i = 0; i < ARRAY_SIZE(ad7746_cap_filter_rate_table); i++)
|
if (val >= ad7746_cap_filter_rate_table[i][0])
|
break;
|
|
if (i >= ARRAY_SIZE(ad7746_cap_filter_rate_table))
|
i = ARRAY_SIZE(ad7746_cap_filter_rate_table) - 1;
|
|
chip->config &= ~AD7746_CONF_CAPFS_MASK;
|
chip->config |= i << AD7746_CONF_CAPFS_SHIFT;
|
|
return 0;
|
}
|
|
static int ad7746_store_vt_filter_rate_setup(struct ad7746_chip_info *chip,
|
int val)
|
{
|
int i;
|
|
for (i = 0; i < ARRAY_SIZE(ad7746_vt_filter_rate_table); i++)
|
if (val >= ad7746_vt_filter_rate_table[i][0])
|
break;
|
|
if (i >= ARRAY_SIZE(ad7746_vt_filter_rate_table))
|
i = ARRAY_SIZE(ad7746_vt_filter_rate_table) - 1;
|
|
chip->config &= ~AD7746_CONF_VTFS_MASK;
|
chip->config |= i << AD7746_CONF_VTFS_SHIFT;
|
|
return 0;
|
}
|
|
static IIO_CONST_ATTR(in_voltage_sampling_frequency_available, "50 31 16 8");
|
static IIO_CONST_ATTR(in_capacitance_sampling_frequency_available,
|
"91 84 50 26 16 13 11 9");
|
|
static struct attribute *ad7746_attributes[] = {
|
&iio_dev_attr_in_capacitance0_calibbias_calibration.dev_attr.attr,
|
&iio_dev_attr_in_capacitance0_calibscale_calibration.dev_attr.attr,
|
&iio_dev_attr_in_capacitance1_calibscale_calibration.dev_attr.attr,
|
&iio_dev_attr_in_capacitance1_calibbias_calibration.dev_attr.attr,
|
&iio_dev_attr_in_voltage0_calibscale_calibration.dev_attr.attr,
|
&iio_const_attr_in_voltage_sampling_frequency_available.dev_attr.attr,
|
&iio_const_attr_in_capacitance_sampling_frequency_available.dev_attr.attr,
|
NULL,
|
};
|
|
static const struct attribute_group ad7746_attribute_group = {
|
.attrs = ad7746_attributes,
|
};
|
|
static int ad7746_write_raw(struct iio_dev *indio_dev,
|
struct iio_chan_spec const *chan,
|
int val,
|
int val2,
|
long mask)
|
{
|
struct ad7746_chip_info *chip = iio_priv(indio_dev);
|
int ret, reg;
|
|
mutex_lock(&chip->lock);
|
|
switch (mask) {
|
case IIO_CHAN_INFO_CALIBSCALE:
|
if (val != 1) {
|
ret = -EINVAL;
|
goto out;
|
}
|
|
val = (val2 * 1024) / 15625;
|
|
switch (chan->type) {
|
case IIO_CAPACITANCE:
|
reg = AD7746_REG_CAP_GAINH;
|
break;
|
case IIO_VOLTAGE:
|
reg = AD7746_REG_VOLT_GAINH;
|
break;
|
default:
|
ret = -EINVAL;
|
goto out;
|
}
|
|
ret = i2c_smbus_write_word_swapped(chip->client, reg, val);
|
if (ret < 0)
|
goto out;
|
|
ret = 0;
|
break;
|
case IIO_CHAN_INFO_CALIBBIAS:
|
if (val < 0 || val > 0xFFFF) {
|
ret = -EINVAL;
|
goto out;
|
}
|
ret = i2c_smbus_write_word_swapped(chip->client,
|
AD7746_REG_CAP_OFFH, val);
|
if (ret < 0)
|
goto out;
|
|
ret = 0;
|
break;
|
case IIO_CHAN_INFO_OFFSET:
|
if (val < 0 || val > 43008000) { /* 21pF */
|
ret = -EINVAL;
|
goto out;
|
}
|
|
/*
|
* CAPDAC Scale = 21pF_typ / 127
|
* CIN Scale = 8.192pF / 2^24
|
* Offset Scale = CAPDAC Scale / CIN Scale = 338646
|
*/
|
|
val /= 338646;
|
|
chip->capdac[chan->channel][chan->differential] = val > 0 ?
|
AD7746_CAPDAC_DACP(val) | AD7746_CAPDAC_DACEN : 0;
|
|
ret = i2c_smbus_write_byte_data(chip->client,
|
AD7746_REG_CAPDACA,
|
chip->capdac[chan->channel][0]);
|
if (ret < 0)
|
goto out;
|
ret = i2c_smbus_write_byte_data(chip->client,
|
AD7746_REG_CAPDACB,
|
chip->capdac[chan->channel][1]);
|
if (ret < 0)
|
goto out;
|
|
chip->capdac_set = chan->channel;
|
|
ret = 0;
|
break;
|
case IIO_CHAN_INFO_SAMP_FREQ:
|
if (val2) {
|
ret = -EINVAL;
|
goto out;
|
}
|
|
switch (chan->type) {
|
case IIO_CAPACITANCE:
|
ret = ad7746_store_cap_filter_rate_setup(chip, val);
|
break;
|
case IIO_VOLTAGE:
|
ret = ad7746_store_vt_filter_rate_setup(chip, val);
|
break;
|
default:
|
ret = -EINVAL;
|
}
|
break;
|
default:
|
ret = -EINVAL;
|
}
|
|
out:
|
mutex_unlock(&chip->lock);
|
return ret;
|
}
|
|
static int ad7746_read_raw(struct iio_dev *indio_dev,
|
struct iio_chan_spec const *chan,
|
int *val, int *val2,
|
long mask)
|
{
|
struct ad7746_chip_info *chip = iio_priv(indio_dev);
|
int ret, delay, idx;
|
u8 regval, reg;
|
|
mutex_lock(&chip->lock);
|
|
switch (mask) {
|
case IIO_CHAN_INFO_RAW:
|
case IIO_CHAN_INFO_PROCESSED:
|
ret = ad7746_select_channel(indio_dev, chan);
|
if (ret < 0)
|
goto out;
|
delay = ret;
|
|
regval = chip->config | AD7746_CONF_MODE_SINGLE_CONV;
|
ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_CFG,
|
regval);
|
if (ret < 0)
|
goto out;
|
|
msleep(delay);
|
/* Now read the actual register */
|
|
ret = i2c_smbus_read_i2c_block_data(chip->client,
|
chan->address >> 8, 3,
|
&chip->data.d8[1]);
|
|
if (ret < 0)
|
goto out;
|
|
*val = (be32_to_cpu(chip->data.d32) & 0xFFFFFF) - 0x800000;
|
|
switch (chan->type) {
|
case IIO_TEMP:
|
/*
|
* temperature in milli degrees Celsius
|
* T = ((*val / 2048) - 4096) * 1000
|
*/
|
*val = (*val * 125) / 256;
|
break;
|
case IIO_VOLTAGE:
|
if (chan->channel == 1) /* supply_raw*/
|
*val = *val * 6;
|
break;
|
default:
|
break;
|
}
|
|
ret = IIO_VAL_INT;
|
break;
|
case IIO_CHAN_INFO_CALIBSCALE:
|
switch (chan->type) {
|
case IIO_CAPACITANCE:
|
reg = AD7746_REG_CAP_GAINH;
|
break;
|
case IIO_VOLTAGE:
|
reg = AD7746_REG_VOLT_GAINH;
|
break;
|
default:
|
ret = -EINVAL;
|
goto out;
|
}
|
|
ret = i2c_smbus_read_word_swapped(chip->client, reg);
|
if (ret < 0)
|
goto out;
|
/* 1 + gain_val / 2^16 */
|
*val = 1;
|
*val2 = (15625 * ret) / 1024;
|
|
ret = IIO_VAL_INT_PLUS_MICRO;
|
break;
|
case IIO_CHAN_INFO_CALIBBIAS:
|
ret = i2c_smbus_read_word_swapped(chip->client,
|
AD7746_REG_CAP_OFFH);
|
if (ret < 0)
|
goto out;
|
*val = ret;
|
|
ret = IIO_VAL_INT;
|
break;
|
case IIO_CHAN_INFO_OFFSET:
|
*val = AD7746_CAPDAC_DACP(chip->capdac[chan->channel]
|
[chan->differential]) * 338646;
|
|
ret = IIO_VAL_INT;
|
break;
|
case IIO_CHAN_INFO_SCALE:
|
switch (chan->type) {
|
case IIO_CAPACITANCE:
|
/* 8.192pf / 2^24 */
|
*val = 0;
|
*val2 = 488;
|
ret = IIO_VAL_INT_PLUS_NANO;
|
break;
|
case IIO_VOLTAGE:
|
/* 1170mV / 2^23 */
|
*val = 1170;
|
*val2 = 23;
|
ret = IIO_VAL_FRACTIONAL_LOG2;
|
break;
|
default:
|
ret = -EINVAL;
|
break;
|
}
|
|
break;
|
case IIO_CHAN_INFO_SAMP_FREQ:
|
switch (chan->type) {
|
case IIO_CAPACITANCE:
|
idx = (chip->config & AD7746_CONF_CAPFS_MASK) >>
|
AD7746_CONF_CAPFS_SHIFT;
|
*val = ad7746_cap_filter_rate_table[idx][0];
|
ret = IIO_VAL_INT;
|
break;
|
case IIO_VOLTAGE:
|
idx = (chip->config & AD7746_CONF_VTFS_MASK) >>
|
AD7746_CONF_VTFS_SHIFT;
|
*val = ad7746_vt_filter_rate_table[idx][0];
|
ret = IIO_VAL_INT;
|
break;
|
default:
|
ret = -EINVAL;
|
}
|
break;
|
default:
|
ret = -EINVAL;
|
}
|
out:
|
mutex_unlock(&chip->lock);
|
return ret;
|
}
|
|
static const struct iio_info ad7746_info = {
|
.attrs = &ad7746_attribute_group,
|
.read_raw = ad7746_read_raw,
|
.write_raw = ad7746_write_raw,
|
};
|
|
/*
|
* device probe and remove
|
*/
|
|
static int ad7746_probe(struct i2c_client *client,
|
const struct i2c_device_id *id)
|
{
|
struct ad7746_platform_data *pdata = client->dev.platform_data;
|
struct ad7746_chip_info *chip;
|
struct iio_dev *indio_dev;
|
unsigned char regval = 0;
|
int ret = 0;
|
|
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
|
if (!indio_dev)
|
return -ENOMEM;
|
chip = iio_priv(indio_dev);
|
mutex_init(&chip->lock);
|
/* this is only used for device removal purposes */
|
i2c_set_clientdata(client, indio_dev);
|
|
chip->client = client;
|
chip->capdac_set = -1;
|
|
indio_dev->name = id->name;
|
indio_dev->info = &ad7746_info;
|
indio_dev->channels = ad7746_channels;
|
if (id->driver_data == 7746)
|
indio_dev->num_channels = ARRAY_SIZE(ad7746_channels);
|
else
|
indio_dev->num_channels = ARRAY_SIZE(ad7746_channels) - 2;
|
indio_dev->modes = INDIO_DIRECT_MODE;
|
|
if (pdata) {
|
if (pdata->exca_en) {
|
if (pdata->exca_inv_en)
|
regval |= AD7746_EXCSETUP_NEXCA;
|
else
|
regval |= AD7746_EXCSETUP_EXCA;
|
}
|
|
if (pdata->excb_en) {
|
if (pdata->excb_inv_en)
|
regval |= AD7746_EXCSETUP_NEXCB;
|
else
|
regval |= AD7746_EXCSETUP_EXCB;
|
}
|
|
regval |= AD7746_EXCSETUP_EXCLVL(pdata->exclvl);
|
} else {
|
dev_warn(&client->dev, "No platform data? using default\n");
|
regval = AD7746_EXCSETUP_EXCA | AD7746_EXCSETUP_EXCB |
|
AD7746_EXCSETUP_EXCLVL(3);
|
}
|
|
ret = i2c_smbus_write_byte_data(chip->client,
|
AD7746_REG_EXC_SETUP, regval);
|
if (ret < 0)
|
return ret;
|
|
ret = devm_iio_device_register(indio_dev->dev.parent, indio_dev);
|
if (ret)
|
return ret;
|
|
return 0;
|
}
|
|
static const struct i2c_device_id ad7746_id[] = {
|
{ "ad7745", 7745 },
|
{ "ad7746", 7746 },
|
{ "ad7747", 7747 },
|
{}
|
};
|
|
MODULE_DEVICE_TABLE(i2c, ad7746_id);
|
|
static const struct of_device_id ad7746_of_match[] = {
|
{ .compatible = "adi,ad7745" },
|
{ .compatible = "adi,ad7746" },
|
{ .compatible = "adi,ad7747" },
|
{ },
|
};
|
|
MODULE_DEVICE_TABLE(of, ad7746_of_match);
|
|
static struct i2c_driver ad7746_driver = {
|
.driver = {
|
.name = KBUILD_MODNAME,
|
.of_match_table = ad7746_of_match,
|
},
|
.probe = ad7746_probe,
|
.id_table = ad7746_id,
|
};
|
module_i2c_driver(ad7746_driver);
|
|
MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
|
MODULE_DESCRIPTION("Analog Devices AD7746/5/7 capacitive sensor driver");
|
MODULE_LICENSE("GPL v2");
|
