blob: fcfc4625431332263273fb9a8395fafcd05b301a [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Texas Instruments ADS131E0x 4-, 6- and 8-Channel ADCs
*
* Copyright (c) 2020 AVL DiTEST GmbH
* Tomislav Denis <tomislav.denis@avl.com>
*
* Datasheet: https://www.ti.com/lit/ds/symlink/ads131e08.pdf
*/
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/iio/buffer.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/trigger.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/regulator/consumer.h>
#include <linux/spi/spi.h>
#include <asm/unaligned.h>
/* Commands */
#define ADS131E08_CMD_RESET 0x06
#define ADS131E08_CMD_START 0x08
#define ADS131E08_CMD_STOP 0x0A
#define ADS131E08_CMD_OFFSETCAL 0x1A
#define ADS131E08_CMD_SDATAC 0x11
#define ADS131E08_CMD_RDATA 0x12
#define ADS131E08_CMD_RREG(r) (BIT(5) | (r & GENMASK(4, 0)))
#define ADS131E08_CMD_WREG(r) (BIT(6) | (r & GENMASK(4, 0)))
/* Registers */
#define ADS131E08_ADR_CFG1R 0x01
#define ADS131E08_ADR_CFG3R 0x03
#define ADS131E08_ADR_CH0R 0x05
/* Configuration register 1 */
#define ADS131E08_CFG1R_DR_MASK GENMASK(2, 0)
/* Configuration register 3 */
#define ADS131E08_CFG3R_PDB_REFBUF_MASK BIT(7)
#define ADS131E08_CFG3R_VREF_4V_MASK BIT(5)
/* Channel settings register */
#define ADS131E08_CHR_GAIN_MASK GENMASK(6, 4)
#define ADS131E08_CHR_MUX_MASK GENMASK(2, 0)
#define ADS131E08_CHR_PWD_MASK BIT(7)
/* ADC misc */
#define ADS131E08_DEFAULT_DATA_RATE 1
#define ADS131E08_DEFAULT_PGA_GAIN 1
#define ADS131E08_DEFAULT_MUX 0
#define ADS131E08_VREF_2V4_mV 2400
#define ADS131E08_VREF_4V_mV 4000
#define ADS131E08_WAIT_RESET_CYCLES 18
#define ADS131E08_WAIT_SDECODE_CYCLES 4
#define ADS131E08_WAIT_OFFSETCAL_MS 153
#define ADS131E08_MAX_SETTLING_TIME_MS 6
#define ADS131E08_NUM_STATUS_BYTES 3
#define ADS131E08_NUM_DATA_BYTES_MAX 24
#define ADS131E08_NUM_DATA_BYTES(dr) (((dr) >= 32) ? 2 : 3)
#define ADS131E08_NUM_DATA_BITS(dr) (ADS131E08_NUM_DATA_BYTES(dr) * 8)
#define ADS131E08_NUM_STORAGE_BYTES 4
enum ads131e08_ids {
ads131e04,
ads131e06,
ads131e08,
};
struct ads131e08_info {
unsigned int max_channels;
const char *name;
};
struct ads131e08_channel_config {
unsigned int pga_gain;
unsigned int mux;
};
struct ads131e08_state {
const struct ads131e08_info *info;
struct spi_device *spi;
struct iio_trigger *trig;
struct clk *adc_clk;
struct regulator *vref_reg;
struct ads131e08_channel_config *channel_config;
unsigned int data_rate;
unsigned int vref_mv;
unsigned int sdecode_delay_us;
unsigned int reset_delay_us;
unsigned int readback_len;
struct completion completion;
struct {
u8 data[ADS131E08_NUM_DATA_BYTES_MAX];
s64 ts __aligned(8);
} tmp_buf;
u8 tx_buf[3] __aligned(IIO_DMA_MINALIGN);
/*
* Add extra one padding byte to be able to access the last channel
* value using u32 pointer
*/
u8 rx_buf[ADS131E08_NUM_STATUS_BYTES +
ADS131E08_NUM_DATA_BYTES_MAX + 1];
};
static const struct ads131e08_info ads131e08_info_tbl[] = {
[ads131e04] = {
.max_channels = 4,
.name = "ads131e04",
},
[ads131e06] = {
.max_channels = 6,
.name = "ads131e06",
},
[ads131e08] = {
.max_channels = 8,
.name = "ads131e08",
},
};
struct ads131e08_data_rate_desc {
unsigned int rate; /* data rate in kSPS */
u8 reg; /* reg value */
};
static const struct ads131e08_data_rate_desc ads131e08_data_rate_tbl[] = {
{ .rate = 64, .reg = 0x00 },
{ .rate = 32, .reg = 0x01 },
{ .rate = 16, .reg = 0x02 },
{ .rate = 8, .reg = 0x03 },
{ .rate = 4, .reg = 0x04 },
{ .rate = 2, .reg = 0x05 },
{ .rate = 1, .reg = 0x06 },
};
struct ads131e08_pga_gain_desc {
unsigned int gain; /* PGA gain value */
u8 reg; /* field value */
};
static const struct ads131e08_pga_gain_desc ads131e08_pga_gain_tbl[] = {
{ .gain = 1, .reg = 0x01 },
{ .gain = 2, .reg = 0x02 },
{ .gain = 4, .reg = 0x04 },
{ .gain = 8, .reg = 0x05 },
{ .gain = 12, .reg = 0x06 },
};
static const u8 ads131e08_valid_channel_mux_values[] = { 0, 1, 3, 4 };
static int ads131e08_exec_cmd(struct ads131e08_state *st, u8 cmd)
{
int ret;
ret = spi_write_then_read(st->spi, &cmd, 1, NULL, 0);
if (ret)
dev_err(&st->spi->dev, "Exec cmd(%02x) failed\n", cmd);
return ret;
}
static int ads131e08_read_reg(struct ads131e08_state *st, u8 reg)
{
int ret;
struct spi_transfer transfer[] = {
{
.tx_buf = &st->tx_buf,
.len = 2,
.delay = {
.value = st->sdecode_delay_us,
.unit = SPI_DELAY_UNIT_USECS,
},
}, {
.rx_buf = &st->rx_buf,
.len = 1,
},
};
st->tx_buf[0] = ADS131E08_CMD_RREG(reg);
st->tx_buf[1] = 0;
ret = spi_sync_transfer(st->spi, transfer, ARRAY_SIZE(transfer));
if (ret) {
dev_err(&st->spi->dev, "Read register failed\n");
return ret;
}
return st->rx_buf[0];
}
static int ads131e08_write_reg(struct ads131e08_state *st, u8 reg, u8 value)
{
int ret;
struct spi_transfer transfer[] = {
{
.tx_buf = &st->tx_buf,
.len = 3,
.delay = {
.value = st->sdecode_delay_us,
.unit = SPI_DELAY_UNIT_USECS,
},
}
};
st->tx_buf[0] = ADS131E08_CMD_WREG(reg);
st->tx_buf[1] = 0;
st->tx_buf[2] = value;
ret = spi_sync_transfer(st->spi, transfer, ARRAY_SIZE(transfer));
if (ret)
dev_err(&st->spi->dev, "Write register failed\n");
return ret;
}
static int ads131e08_read_data(struct ads131e08_state *st, int rx_len)
{
int ret;
struct spi_transfer transfer[] = {
{
.tx_buf = &st->tx_buf,
.len = 1,
}, {
.rx_buf = &st->rx_buf,
.len = rx_len,
},
};
st->tx_buf[0] = ADS131E08_CMD_RDATA;
ret = spi_sync_transfer(st->spi, transfer, ARRAY_SIZE(transfer));
if (ret)
dev_err(&st->spi->dev, "Read data failed\n");
return ret;
}
static int ads131e08_set_data_rate(struct ads131e08_state *st, int data_rate)
{
int i, reg, ret;
for (i = 0; i < ARRAY_SIZE(ads131e08_data_rate_tbl); i++) {
if (ads131e08_data_rate_tbl[i].rate == data_rate)
break;
}
if (i == ARRAY_SIZE(ads131e08_data_rate_tbl)) {
dev_err(&st->spi->dev, "invalid data rate value\n");
return -EINVAL;
}
reg = ads131e08_read_reg(st, ADS131E08_ADR_CFG1R);
if (reg < 0)
return reg;
reg &= ~ADS131E08_CFG1R_DR_MASK;
reg |= FIELD_PREP(ADS131E08_CFG1R_DR_MASK,
ads131e08_data_rate_tbl[i].reg);
ret = ads131e08_write_reg(st, ADS131E08_ADR_CFG1R, reg);
if (ret)
return ret;
st->data_rate = data_rate;
st->readback_len = ADS131E08_NUM_STATUS_BYTES +
ADS131E08_NUM_DATA_BYTES(st->data_rate) *
st->info->max_channels;
return 0;
}
static int ads131e08_pga_gain_to_field_value(struct ads131e08_state *st,
unsigned int pga_gain)
{
int i;
for (i = 0; i < ARRAY_SIZE(ads131e08_pga_gain_tbl); i++) {
if (ads131e08_pga_gain_tbl[i].gain == pga_gain)
break;
}
if (i == ARRAY_SIZE(ads131e08_pga_gain_tbl)) {
dev_err(&st->spi->dev, "invalid PGA gain value\n");
return -EINVAL;
}
return ads131e08_pga_gain_tbl[i].reg;
}
static int ads131e08_set_pga_gain(struct ads131e08_state *st,
unsigned int channel, unsigned int pga_gain)
{
int field_value, reg;
field_value = ads131e08_pga_gain_to_field_value(st, pga_gain);
if (field_value < 0)
return field_value;
reg = ads131e08_read_reg(st, ADS131E08_ADR_CH0R + channel);
if (reg < 0)
return reg;
reg &= ~ADS131E08_CHR_GAIN_MASK;
reg |= FIELD_PREP(ADS131E08_CHR_GAIN_MASK, field_value);
return ads131e08_write_reg(st, ADS131E08_ADR_CH0R + channel, reg);
}
static int ads131e08_validate_channel_mux(struct ads131e08_state *st,
unsigned int mux)
{
int i;
for (i = 0; i < ARRAY_SIZE(ads131e08_valid_channel_mux_values); i++) {
if (ads131e08_valid_channel_mux_values[i] == mux)
break;
}
if (i == ARRAY_SIZE(ads131e08_valid_channel_mux_values)) {
dev_err(&st->spi->dev, "invalid channel mux value\n");
return -EINVAL;
}
return 0;
}
static int ads131e08_set_channel_mux(struct ads131e08_state *st,
unsigned int channel, unsigned int mux)
{
int reg;
reg = ads131e08_read_reg(st, ADS131E08_ADR_CH0R + channel);
if (reg < 0)
return reg;
reg &= ~ADS131E08_CHR_MUX_MASK;
reg |= FIELD_PREP(ADS131E08_CHR_MUX_MASK, mux);
return ads131e08_write_reg(st, ADS131E08_ADR_CH0R + channel, reg);
}
static int ads131e08_power_down_channel(struct ads131e08_state *st,
unsigned int channel, bool value)
{
int reg;
reg = ads131e08_read_reg(st, ADS131E08_ADR_CH0R + channel);
if (reg < 0)
return reg;
reg &= ~ADS131E08_CHR_PWD_MASK;
reg |= FIELD_PREP(ADS131E08_CHR_PWD_MASK, value);
return ads131e08_write_reg(st, ADS131E08_ADR_CH0R + channel, reg);
}
static int ads131e08_config_reference_voltage(struct ads131e08_state *st)
{
int reg;
reg = ads131e08_read_reg(st, ADS131E08_ADR_CFG3R);
if (reg < 0)
return reg;
reg &= ~ADS131E08_CFG3R_PDB_REFBUF_MASK;
if (!st->vref_reg) {
reg |= FIELD_PREP(ADS131E08_CFG3R_PDB_REFBUF_MASK, 1);
reg &= ~ADS131E08_CFG3R_VREF_4V_MASK;
reg |= FIELD_PREP(ADS131E08_CFG3R_VREF_4V_MASK,
st->vref_mv == ADS131E08_VREF_4V_mV);
}
return ads131e08_write_reg(st, ADS131E08_ADR_CFG3R, reg);
}
static int ads131e08_initial_config(struct iio_dev *indio_dev)
{
const struct iio_chan_spec *channel = indio_dev->channels;
struct ads131e08_state *st = iio_priv(indio_dev);
unsigned long active_channels = 0;
int ret, i;
ret = ads131e08_exec_cmd(st, ADS131E08_CMD_RESET);
if (ret)
return ret;
udelay(st->reset_delay_us);
/* Disable read data in continuous mode (enabled by default) */
ret = ads131e08_exec_cmd(st, ADS131E08_CMD_SDATAC);
if (ret)
return ret;
ret = ads131e08_set_data_rate(st, ADS131E08_DEFAULT_DATA_RATE);
if (ret)
return ret;
ret = ads131e08_config_reference_voltage(st);
if (ret)
return ret;
for (i = 0; i < indio_dev->num_channels; i++) {
ret = ads131e08_set_pga_gain(st, channel->channel,
st->channel_config[i].pga_gain);
if (ret)
return ret;
ret = ads131e08_set_channel_mux(st, channel->channel,
st->channel_config[i].mux);
if (ret)
return ret;
active_channels |= BIT(channel->channel);
channel++;
}
/* Power down unused channels */
for_each_clear_bit(i, &active_channels, st->info->max_channels) {
ret = ads131e08_power_down_channel(st, i, true);
if (ret)
return ret;
}
/* Request channel offset calibration */
ret = ads131e08_exec_cmd(st, ADS131E08_CMD_OFFSETCAL);
if (ret)
return ret;
/*
* Channel offset calibration is triggered with the first START
* command. Since calibration takes more time than settling operation,
* this causes timeout error when command START is sent first
* time (e.g. first call of the ads131e08_read_direct method).
* To avoid this problem offset calibration is triggered here.
*/
ret = ads131e08_exec_cmd(st, ADS131E08_CMD_START);
if (ret)
return ret;
msleep(ADS131E08_WAIT_OFFSETCAL_MS);
return ads131e08_exec_cmd(st, ADS131E08_CMD_STOP);
}
static int ads131e08_pool_data(struct ads131e08_state *st)
{
unsigned long timeout;
int ret;
reinit_completion(&st->completion);
ret = ads131e08_exec_cmd(st, ADS131E08_CMD_START);
if (ret)
return ret;
timeout = msecs_to_jiffies(ADS131E08_MAX_SETTLING_TIME_MS);
ret = wait_for_completion_timeout(&st->completion, timeout);
if (!ret)
return -ETIMEDOUT;
ret = ads131e08_read_data(st, st->readback_len);
if (ret)
return ret;
return ads131e08_exec_cmd(st, ADS131E08_CMD_STOP);
}
static int ads131e08_read_direct(struct iio_dev *indio_dev,
struct iio_chan_spec const *channel, int *value)
{
struct ads131e08_state *st = iio_priv(indio_dev);
u8 num_bits, *src;
int ret;
ret = ads131e08_pool_data(st);
if (ret)
return ret;
src = st->rx_buf + ADS131E08_NUM_STATUS_BYTES +
channel->channel * ADS131E08_NUM_DATA_BYTES(st->data_rate);
num_bits = ADS131E08_NUM_DATA_BITS(st->data_rate);
*value = sign_extend32(get_unaligned_be32(src) >> (32 - num_bits), num_bits - 1);
return 0;
}
static int ads131e08_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *channel, int *value,
int *value2, long mask)
{
struct ads131e08_state *st = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = iio_device_claim_direct_mode(indio_dev);
if (ret)
return ret;
ret = ads131e08_read_direct(indio_dev, channel, value);
iio_device_release_direct_mode(indio_dev);
if (ret)
return ret;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
if (st->vref_reg) {
ret = regulator_get_voltage(st->vref_reg);
if (ret < 0)
return ret;
*value = ret / 1000;
} else {
*value = st->vref_mv;
}
*value /= st->channel_config[channel->address].pga_gain;
*value2 = ADS131E08_NUM_DATA_BITS(st->data_rate) - 1;
return IIO_VAL_FRACTIONAL_LOG2;
case IIO_CHAN_INFO_SAMP_FREQ:
*value = st->data_rate;
return IIO_VAL_INT;
default:
return -EINVAL;
}
}
static int ads131e08_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *channel, int value,
int value2, long mask)
{
struct ads131e08_state *st = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_SAMP_FREQ:
ret = iio_device_claim_direct_mode(indio_dev);
if (ret)
return ret;
ret = ads131e08_set_data_rate(st, value);
iio_device_release_direct_mode(indio_dev);
return ret;
default:
return -EINVAL;
}
}
static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("1 2 4 8 16 32 64");
static struct attribute *ads131e08_attributes[] = {
&iio_const_attr_sampling_frequency_available.dev_attr.attr,
NULL
};
static const struct attribute_group ads131e08_attribute_group = {
.attrs = ads131e08_attributes,
};
static int ads131e08_debugfs_reg_access(struct iio_dev *indio_dev,
unsigned int reg, unsigned int writeval, unsigned int *readval)
{
struct ads131e08_state *st = iio_priv(indio_dev);
if (readval) {
int ret = ads131e08_read_reg(st, reg);
*readval = ret;
return ret;
}
return ads131e08_write_reg(st, reg, writeval);
}
static const struct iio_info ads131e08_iio_info = {
.read_raw = ads131e08_read_raw,
.write_raw = ads131e08_write_raw,
.attrs = &ads131e08_attribute_group,
.debugfs_reg_access = &ads131e08_debugfs_reg_access,
};
static int ads131e08_set_trigger_state(struct iio_trigger *trig, bool state)
{
struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
struct ads131e08_state *st = iio_priv(indio_dev);
u8 cmd = state ? ADS131E08_CMD_START : ADS131E08_CMD_STOP;
return ads131e08_exec_cmd(st, cmd);
}
static const struct iio_trigger_ops ads131e08_trigger_ops = {
.set_trigger_state = &ads131e08_set_trigger_state,
.validate_device = &iio_trigger_validate_own_device,
};
static irqreturn_t ads131e08_trigger_handler(int irq, void *private)
{
struct iio_poll_func *pf = private;
struct iio_dev *indio_dev = pf->indio_dev;
struct ads131e08_state *st = iio_priv(indio_dev);
unsigned int chn, i = 0;
u8 *src, *dest;
int ret;
/*
* The number of data bits per channel depends on the data rate.
* For 32 and 64 ksps data rates, number of data bits per channel
* is 16. This case is not compliant with used (fixed) scan element
* type (be:s24/32>>8). So we use a little tweak to pack properly
* 16 bits of data into the buffer.
*/
unsigned int num_bytes = ADS131E08_NUM_DATA_BYTES(st->data_rate);
u8 tweek_offset = num_bytes == 2 ? 1 : 0;
if (iio_trigger_using_own(indio_dev))
ret = ads131e08_read_data(st, st->readback_len);
else
ret = ads131e08_pool_data(st);
if (ret)
goto out;
for_each_set_bit(chn, indio_dev->active_scan_mask, indio_dev->masklength) {
src = st->rx_buf + ADS131E08_NUM_STATUS_BYTES + chn * num_bytes;
dest = st->tmp_buf.data + i * ADS131E08_NUM_STORAGE_BYTES;
/*
* Tweek offset is 0:
* +---+---+---+---+
* |D0 |D1 |D2 | X | (3 data bytes)
* +---+---+---+---+
* a+0 a+1 a+2 a+3
*
* Tweek offset is 1:
* +---+---+---+---+
* |P0 |D0 |D1 | X | (one padding byte and 2 data bytes)
* +---+---+---+---+
* a+0 a+1 a+2 a+3
*/
memcpy(dest + tweek_offset, src, num_bytes);
/*
* Data conversion from 16 bits of data to 24 bits of data
* is done by sign extension (properly filling padding byte).
*/
if (tweek_offset)
*dest = *src & BIT(7) ? 0xff : 0x00;
i++;
}
iio_push_to_buffers_with_timestamp(indio_dev, st->tmp_buf.data,
iio_get_time_ns(indio_dev));
out:
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static irqreturn_t ads131e08_interrupt(int irq, void *private)
{
struct iio_dev *indio_dev = private;
struct ads131e08_state *st = iio_priv(indio_dev);
if (iio_buffer_enabled(indio_dev) && iio_trigger_using_own(indio_dev))
iio_trigger_poll(st->trig);
else
complete(&st->completion);
return IRQ_HANDLED;
}
static int ads131e08_alloc_channels(struct iio_dev *indio_dev)
{
struct ads131e08_state *st = iio_priv(indio_dev);
struct ads131e08_channel_config *channel_config;
struct device *dev = &st->spi->dev;
struct iio_chan_spec *channels;
struct fwnode_handle *node;
unsigned int channel, tmp;
int num_channels, i, ret;
ret = device_property_read_u32(dev, "ti,vref-internal", &tmp);
if (ret)
tmp = 0;
switch (tmp) {
case 0:
st->vref_mv = ADS131E08_VREF_2V4_mV;
break;
case 1:
st->vref_mv = ADS131E08_VREF_4V_mV;
break;
default:
dev_err(&st->spi->dev, "invalid internal voltage reference\n");
return -EINVAL;
}
num_channels = device_get_child_node_count(dev);
if (num_channels == 0) {
dev_err(&st->spi->dev, "no channel children\n");
return -ENODEV;
}
if (num_channels > st->info->max_channels) {
dev_err(&st->spi->dev, "num of channel children out of range\n");
return -EINVAL;
}
channels = devm_kcalloc(&st->spi->dev, num_channels,
sizeof(*channels), GFP_KERNEL);
if (!channels)
return -ENOMEM;
channel_config = devm_kcalloc(&st->spi->dev, num_channels,
sizeof(*channel_config), GFP_KERNEL);
if (!channel_config)
return -ENOMEM;
i = 0;
device_for_each_child_node(dev, node) {
ret = fwnode_property_read_u32(node, "reg", &channel);
if (ret)
goto err_child_out;
ret = fwnode_property_read_u32(node, "ti,gain", &tmp);
if (ret) {
channel_config[i].pga_gain = ADS131E08_DEFAULT_PGA_GAIN;
} else {
ret = ads131e08_pga_gain_to_field_value(st, tmp);
if (ret < 0)
goto err_child_out;
channel_config[i].pga_gain = tmp;
}
ret = fwnode_property_read_u32(node, "ti,mux", &tmp);
if (ret) {
channel_config[i].mux = ADS131E08_DEFAULT_MUX;
} else {
ret = ads131e08_validate_channel_mux(st, tmp);
if (ret)
goto err_child_out;
channel_config[i].mux = tmp;
}
channels[i].type = IIO_VOLTAGE;
channels[i].indexed = 1;
channels[i].channel = channel;
channels[i].address = i;
channels[i].info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE);
channels[i].info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ);
channels[i].scan_index = channel;
channels[i].scan_type.sign = 's';
channels[i].scan_type.realbits = 24;
channels[i].scan_type.storagebits = 32;
channels[i].scan_type.shift = 8;
channels[i].scan_type.endianness = IIO_BE;
i++;
}
indio_dev->channels = channels;
indio_dev->num_channels = num_channels;
st->channel_config = channel_config;
return 0;
err_child_out:
fwnode_handle_put(node);
return ret;
}
static void ads131e08_regulator_disable(void *data)
{
struct ads131e08_state *st = data;
regulator_disable(st->vref_reg);
}
static int ads131e08_probe(struct spi_device *spi)
{
const struct ads131e08_info *info;
struct ads131e08_state *st;
struct iio_dev *indio_dev;
unsigned long adc_clk_hz;
unsigned long adc_clk_ns;
int ret;
info = device_get_match_data(&spi->dev);
if (!info)
info = (void *)spi_get_device_id(spi)->driver_data;
if (!info) {
dev_err(&spi->dev, "failed to get match data\n");
return -ENODEV;
}
indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
if (!indio_dev) {
dev_err(&spi->dev, "failed to allocate IIO device\n");
return -ENOMEM;
}
st = iio_priv(indio_dev);
st->info = info;
st->spi = spi;
ret = ads131e08_alloc_channels(indio_dev);
if (ret)
return ret;
indio_dev->name = st->info->name;
indio_dev->info = &ads131e08_iio_info;
indio_dev->modes = INDIO_DIRECT_MODE;
init_completion(&st->completion);
if (spi->irq) {
ret = devm_request_irq(&spi->dev, spi->irq,
ads131e08_interrupt,
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
spi->dev.driver->name, indio_dev);
if (ret)
return dev_err_probe(&spi->dev, ret,
"request irq failed\n");
} else {
dev_err(&spi->dev, "data ready IRQ missing\n");
return -ENODEV;
}
st->trig = devm_iio_trigger_alloc(&spi->dev, "%s-dev%d",
indio_dev->name, iio_device_id(indio_dev));
if (!st->trig) {
dev_err(&spi->dev, "failed to allocate IIO trigger\n");
return -ENOMEM;
}
st->trig->ops = &ads131e08_trigger_ops;
st->trig->dev.parent = &spi->dev;
iio_trigger_set_drvdata(st->trig, indio_dev);
ret = devm_iio_trigger_register(&spi->dev, st->trig);
if (ret) {
dev_err(&spi->dev, "failed to register IIO trigger\n");
return -ENOMEM;
}
indio_dev->trig = iio_trigger_get(st->trig);
ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
NULL, &ads131e08_trigger_handler, NULL);
if (ret) {
dev_err(&spi->dev, "failed to setup IIO buffer\n");
return ret;
}
st->vref_reg = devm_regulator_get_optional(&spi->dev, "vref");
if (!IS_ERR(st->vref_reg)) {
ret = regulator_enable(st->vref_reg);
if (ret) {
dev_err(&spi->dev,
"failed to enable external vref supply\n");
return ret;
}
ret = devm_add_action_or_reset(&spi->dev, ads131e08_regulator_disable, st);
if (ret)
return ret;
} else {
if (PTR_ERR(st->vref_reg) != -ENODEV)
return PTR_ERR(st->vref_reg);
st->vref_reg = NULL;
}
st->adc_clk = devm_clk_get_enabled(&spi->dev, "adc-clk");
if (IS_ERR(st->adc_clk))
return dev_err_probe(&spi->dev, PTR_ERR(st->adc_clk),
"failed to get the ADC clock\n");
adc_clk_hz = clk_get_rate(st->adc_clk);
if (!adc_clk_hz) {
dev_err(&spi->dev, "failed to get the ADC clock rate\n");
return -EINVAL;
}
adc_clk_ns = NSEC_PER_SEC / adc_clk_hz;
st->sdecode_delay_us = DIV_ROUND_UP(
ADS131E08_WAIT_SDECODE_CYCLES * adc_clk_ns, NSEC_PER_USEC);
st->reset_delay_us = DIV_ROUND_UP(
ADS131E08_WAIT_RESET_CYCLES * adc_clk_ns, NSEC_PER_USEC);
ret = ads131e08_initial_config(indio_dev);
if (ret) {
dev_err(&spi->dev, "initial configuration failed\n");
return ret;
}
return devm_iio_device_register(&spi->dev, indio_dev);
}
static const struct of_device_id ads131e08_of_match[] = {
{ .compatible = "ti,ads131e04",
.data = &ads131e08_info_tbl[ads131e04], },
{ .compatible = "ti,ads131e06",
.data = &ads131e08_info_tbl[ads131e06], },
{ .compatible = "ti,ads131e08",
.data = &ads131e08_info_tbl[ads131e08], },
{}
};
MODULE_DEVICE_TABLE(of, ads131e08_of_match);
static const struct spi_device_id ads131e08_ids[] = {
{ "ads131e04", (kernel_ulong_t)&ads131e08_info_tbl[ads131e04] },
{ "ads131e06", (kernel_ulong_t)&ads131e08_info_tbl[ads131e06] },
{ "ads131e08", (kernel_ulong_t)&ads131e08_info_tbl[ads131e08] },
{}
};
MODULE_DEVICE_TABLE(spi, ads131e08_ids);
static struct spi_driver ads131e08_driver = {
.driver = {
.name = "ads131e08",
.of_match_table = ads131e08_of_match,
},
.probe = ads131e08_probe,
.id_table = ads131e08_ids,
};
module_spi_driver(ads131e08_driver);
MODULE_AUTHOR("Tomislav Denis <tomislav.denis@avl.com>");
MODULE_DESCRIPTION("Driver for ADS131E0x ADC family");
MODULE_LICENSE("GPL v2");