// SPDX-License-Identifier: GPL-2.0-only
/*
* MAX11410 SPI ADC driver
*
* Copyright 2022 Analog Devices Inc.
*/
#include <linux/bitfield.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/spi/spi.h>
#include <linux/unaligned.h>
#include <linux/iio/buffer.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/trigger.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#define MAX11410_REG_CONV_START 0x01
#define MAX11410_CONV_TYPE_SINGLE 0x00
#define MAX11410_CONV_TYPE_CONTINUOUS 0x01
#define MAX11410_REG_CAL_START 0x03
#define MAX11410_CAL_START_SELF 0x00
#define MAX11410_CAL_START_PGA 0x01
#define MAX11410_REG_GPIO_CTRL(ch) ((ch) ? 0x05 : 0x04)
#define MAX11410_GPIO_INTRB 0xC1
#define MAX11410_REG_FILTER 0x08
#define MAX11410_FILTER_RATE_MASK GENMASK(3, 0)
#define MAX11410_FILTER_RATE_MAX 0x0F
#define MAX11410_FILTER_LINEF_MASK GENMASK(5, 4)
#define MAX11410_FILTER_50HZ BIT(5)
#define MAX11410_FILTER_60HZ BIT(4)
#define MAX11410_REG_CTRL 0x09
#define MAX11410_CTRL_REFSEL_MASK GENMASK(2, 0)
#define MAX11410_CTRL_VREFN_BUF_BIT BIT(3)
#define MAX11410_CTRL_VREFP_BUF_BIT BIT(4)
#define MAX11410_CTRL_FORMAT_BIT BIT(5)
#define MAX11410_CTRL_UNIPOLAR_BIT BIT(6)
#define MAX11410_REG_MUX_CTRL0 0x0B
#define MAX11410_REG_PGA 0x0E
#define MAX11410_PGA_GAIN_MASK GENMASK(2, 0)
#define MAX11410_PGA_SIG_PATH_MASK GENMASK(5, 4)
#define MAX11410_PGA_SIG_PATH_BUFFERED 0x00
#define MAX11410_PGA_SIG_PATH_BYPASS 0x01
#define MAX11410_PGA_SIG_PATH_PGA 0x02
#define MAX11410_REG_DATA0 0x30
#define MAX11410_REG_STATUS 0x38
#define MAX11410_STATUS_CONV_READY_BIT BIT(0)
#define MAX11410_STATUS_CAL_READY_BIT BIT(2)
#define MAX11410_REFSEL_AVDD_AGND 0x03
#define MAX11410_REFSEL_MAX 0x06
#define MAX11410_SIG_PATH_MAX 0x02
#define MAX11410_CHANNEL_INDEX_MAX 0x0A
#define MAX11410_AINP_AVDD 0x0A
#define MAX11410_AINN_GND 0x0A
#define MAX11410_CONVERSION_TIMEOUT_MS 2000
#define MAX11410_CALIB_TIMEOUT_MS 2000
#define MAX11410_SCALE_AVAIL_SIZE 8
enum max11410_filter {
MAX11410_FILTER_FIR5060,
MAX11410_FILTER_FIR50,
MAX11410_FILTER_FIR60,
MAX11410_FILTER_SINC4,
};
static const u8 max11410_sampling_len[] = {
[MAX11410_FILTER_FIR5060] = 5,
[MAX11410_FILTER_FIR50] = 6,
[MAX11410_FILTER_FIR60] = 6,
[MAX11410_FILTER_SINC4] = 10,
};
static const int max11410_sampling_rates[4][10][2] = {
[MAX11410_FILTER_FIR5060] = {
{ 1, 100000 },
{ 2, 100000 },
{ 4, 200000 },
{ 8, 400000 },
{ 16, 800000 }
},
[MAX11410_FILTER_FIR50] = {
{ 1, 300000 },
{ 2, 700000 },
{ 5, 300000 },
{ 10, 700000 },
{ 21, 300000 },
{ 40 }
},
[MAX11410_FILTER_FIR60] = {
{ 1, 300000 },
{ 2, 700000 },
{ 5, 300000 },
{ 10, 700000 },
{ 21, 300000 },
{ 40 }
},
[MAX11410_FILTER_SINC4] = {
{ 4 },
{ 10 },
{ 20 },
{ 40 },
{ 60 },
{ 120 },
{ 240 },
{ 480 },
{ 960 },
{ 1920 }
}
};
struct max11410_channel_config {
u32 settling_time_us;
u32 *scale_avail;
u8 refsel;
u8 sig_path;
u8 gain;
bool bipolar;
bool buffered_vrefp;
bool buffered_vrefn;
};
struct max11410_state {
struct spi_device *spi_dev;
struct iio_trigger *trig;
struct completion completion;
struct mutex lock; /* Prevent changing channel config during sampling */
struct regmap *regmap;
struct regulator *avdd;
struct regulator *vrefp[3];
struct regulator *vrefn[3];
struct max11410_channel_config *channels;
int irq;
struct {
u32 data __aligned(IIO_DMA_MINALIGN);
s64 ts __aligned(8);
} scan;
};
static const struct iio_chan_spec chanspec_template = {
.type = IIO_VOLTAGE,
.indexed = 1,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE) |
BIT(IIO_CHAN_INFO_OFFSET),
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),
.scan_type = {
.sign = 's',
.realbits = 24,
.storagebits = 32,
.endianness = IIO_LE,
},
};
static unsigned int max11410_reg_size(unsigned int reg)
{
/* Registers from 0x00 to 0x10 are 1 byte, the rest are 3 bytes long. */
return reg <= 0x10 ? 1 : 3;
}
static int max11410_write_reg(struct max11410_state *st, unsigned int reg,
unsigned int val)
{
/* This driver only needs to write 8-bit registers */
if (max11410_reg_size(reg) != 1)
return -EINVAL;
return regmap_write(st->regmap, reg, val);
}
static int max11410_read_reg(struct max11410_state *st, unsigned int reg,
int *val)
{
int ret;
if (max11410_reg_size(reg) == 3) {
ret = regmap_bulk_read(st->regmap, reg, &st->scan.data, 3);
if (ret)
return ret;
*val = get_unaligned_be24(&st->scan.data);
return 0;
}
return regmap_read(st->regmap, reg, val);
}
static struct regulator *max11410_get_vrefp(struct max11410_state *st,
u8 refsel)
{
refsel = refsel % 4;
if (refsel == 3)
return st->avdd;
return st->vrefp[refsel];
}
static struct regulator *max11410_get_vrefn(struct max11410_state *st,
u8 refsel)
{
if (refsel > 2)
return NULL;
return st->vrefn[refsel];
}
static const struct regmap_config regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = 0x39,
};
static ssize_t max11410_notch_en_show(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct max11410_state *state = iio_priv(indio_dev);
struct iio_dev_attr *iio_attr = to_iio_dev_attr(devattr);
unsigned int val;
int ret;
ret = max11410_read_reg(state, MAX11410_REG_FILTER, &val);
if (ret)
return ret;
switch (iio_attr->address) {
case 0:
val = !FIELD_GET(MAX11410_FILTER_50HZ, val);
break;
case 1:
val = !FIELD_GET(MAX11410_FILTER_60HZ, val);
break;
case 2:
val = FIELD_GET(MAX11410_FILTER_LINEF_MASK, val) == 3;
break;
default:
return -EINVAL;
}
return sysfs_emit(buf, "%d\n", val);
}
static ssize_t max11410_notch_en_store(struct device *dev,
struct device_attribute *devattr,
const char *buf, size_t count)
{
struct iio_dev_attr *iio_attr = to_iio_dev_attr(devattr);
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct max11410_state *state = iio_priv(indio_dev);
unsigned int filter_bits;
bool enable;
int ret;
ret = kstrtobool(buf, &enable);
if (ret)
return ret;
switch (iio_attr->address) {
case 0:
filter_bits = MAX11410_FILTER_50HZ;
break;
case 1:
filter_bits = MAX11410_FILTER_60HZ;
break;
case 2:
default:
filter_bits = MAX11410_FILTER_50HZ | MAX11410_FILTER_60HZ;
enable = !enable;
break;
}
if (enable)
ret = regmap_clear_bits(state->regmap, MAX11410_REG_FILTER,
filter_bits);
else
ret = regmap_set_bits(state->regmap, MAX11410_REG_FILTER,
filter_bits);
if (ret)
return ret;
return count;
}
static ssize_t in_voltage_filter2_notch_center_show(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct max11410_state *state = iio_priv(indio_dev);
int ret, reg, rate, filter;
ret = regmap_read(state->regmap, MAX11410_REG_FILTER, ®);
if (ret)
return ret;
rate = FIELD_GET(MAX11410_FILTER_RATE_MASK, reg);
rate = clamp_val(rate, 0,
max11410_sampling_len[MAX11410_FILTER_SINC4] - 1);
filter = max11410_sampling_rates[MAX11410_FILTER_SINC4][rate][0];
return sysfs_emit(buf, "%d\n", filter);
}
static IIO_CONST_ATTR(in_voltage_filter0_notch_center, "50");
static IIO_CONST_ATTR(in_voltage_filter1_notch_center, "60");
static IIO_DEVICE_ATTR_RO(in_voltage_filter2_notch_center, 2);
static IIO_DEVICE_ATTR(in_voltage_filter0_notch_en, 0644,
max11410_notch_en_show, max11410_notch_en_store, 0);
static IIO_DEVICE_ATTR(in_voltage_filter1_notch_en, 0644,
max11410_notch_en_show, max11410_notch_en_store, 1);
static IIO_DEVICE_ATTR(in_voltage_filter2_notch_en, 0644,
max11410_notch_en_show, max11410_notch_en_store, 2);
static struct attribute *max11410_attributes[] = {
&iio_const_attr_in_voltage_filter0_notch_center.dev_attr.attr,
&iio_const_attr_in_voltage_filter1_notch_center.dev_attr.attr,
&iio_dev_attr_in_voltage_filter2_notch_center.dev_attr.attr,
&iio_dev_attr_in_voltage_filter0_notch_en.dev_attr.attr,
&iio_dev_attr_in_voltage_filter1_notch_en.dev_attr.attr,
&iio_dev_attr_in_voltage_filter2_notch_en.dev_attr.attr,
NULL
};
static const struct attribute_group max11410_attribute_group = {
.attrs = max11410_attributes,
};
static int max11410_set_input_mux(struct max11410_state *st, u8 ainp, u8 ainn)
{
if (ainp > MAX11410_CHANNEL_INDEX_MAX ||
ainn > MAX11410_CHANNEL_INDEX_MAX)
return -EINVAL;
return max11410_write_reg(st, MAX11410_REG_MUX_CTRL0,
(ainp << 4) | ainn);
}
static int max11410_configure_channel(struct max11410_state *st,
struct iio_chan_spec const *chan)
{
struct max11410_channel_config cfg = st->channels[chan->address];
unsigned int regval;
int ret;
if (chan->differential)
ret = max11410_set_input_mux(st, chan->channel, chan->channel2);
else
ret = max11410_set_input_mux(st, chan->channel,
MAX11410_AINN_GND);
if (ret)
return ret;
regval = FIELD_PREP(MAX11410_CTRL_VREFP_BUF_BIT, cfg.buffered_vrefp) |
FIELD_PREP(MAX11410_CTRL_VREFN_BUF_BIT, cfg.buffered_vrefn) |
FIELD_PREP(MAX11410_CTRL_REFSEL_MASK, cfg.refsel) |
FIELD_PREP(MAX11410_CTRL_UNIPOLAR_BIT, cfg.bipolar ? 0 : 1);
ret = regmap_update_bits(st->regmap, MAX11410_REG_CTRL,
MAX11410_CTRL_REFSEL_MASK |
MAX11410_CTRL_VREFP_BUF_BIT |
MAX11410_CTRL_VREFN_BUF_BIT |
MAX11410_CTRL_UNIPOLAR_BIT, regval);
if (ret)
return ret;
regval = FIELD_PREP(MAX11410_PGA_SIG_PATH_MASK, cfg.sig_path) |
FIELD_PREP(MAX11410_PGA_GAIN_MASK, cfg.gain);
ret = regmap_write(st->regmap, MAX11410_REG_PGA, regval);
if (ret)
return ret;
if (cfg.settling_time_us)
fsleep(cfg.settling_time_us);
return 0;
}
static int max11410_sample(struct max11410_state *st, int *sample_raw,
struct iio_chan_spec const *chan)
{
int val, ret;
ret = max11410_configure_channel(st, chan);
if (ret)
return ret;
if (st->irq > 0)
reinit_completion(&st->completion);
/* Start Conversion */
ret = max11410_write_reg(st, MAX11410_REG_CONV_START,
MAX11410_CONV_TYPE_SINGLE);
if (ret)
return ret;
if (st->irq > 0) {
/* Wait for an interrupt. */
ret = wait_for_completion_timeout(&st->completion,
msecs_to_jiffies(MAX11410_CONVERSION_TIMEOUT_MS));
if (!ret)
return -ETIMEDOUT;
} else {
int ret2;
/* Wait for status register Conversion Ready flag */
ret = read_poll_timeout(max11410_read_reg, ret2,
ret2 || (val & MAX11410_STATUS_CONV_READY_BIT),
5000, MAX11410_CONVERSION_TIMEOUT_MS * 1000,
true, st, MAX11410_REG_STATUS, &val);
if (ret)
return ret;
if (ret2)
return ret2;
}
/* Read ADC Data */
return max11410_read_reg(st, MAX11410_REG_DATA0, sample_raw);
}
static int max11410_get_scale(struct max11410_state *state,
struct max11410_channel_config cfg)
{
struct regulator *vrefp, *vrefn;
int scale;
vrefp = max11410_get_vrefp(state, cfg.refsel);
scale = regulator_get_voltage(vrefp) / 1000;
vrefn = max11410_get_vrefn(state, cfg.refsel);
if (vrefn)
scale -= regulator_get_voltage(vrefn) / 1000;
if (cfg.bipolar)
scale *= 2;
return scale >> cfg.gain;
}
static int max11410_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long info)
{
struct max11410_state *state = iio_priv(indio_dev);
struct max11410_channel_config cfg = state->channels[chan->address];
int ret, reg_val, filter, rate;
switch (info) {
case IIO_CHAN_INFO_SCALE:
*val = max11410_get_scale(state, cfg);
*val2 = chan->scan_type.realbits;
return IIO_VAL_FRACTIONAL_LOG2;
case IIO_CHAN_INFO_OFFSET:
if (cfg.bipolar)
*val = -BIT(chan->scan_type.realbits - 1);
else
*val = 0;
return IIO_VAL_INT;
case IIO_CHAN_INFO_RAW:
ret = iio_device_claim_direct_mode(indio_dev);
if (ret)
return ret;
mutex_lock(&state->lock);
ret = max11410_sample(state, ®_val, chan);
mutex_unlock(&state->lock);
iio_device_release_direct_mode(indio_dev);
if (ret)
return ret;
*val = reg_val;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SAMP_FREQ:
ret = regmap_read(state->regmap, MAX11410_REG_FILTER, ®_val);
if (ret)
return ret;
filter = FIELD_GET(MAX11410_FILTER_LINEF_MASK, reg_val);
rate = reg_val & MAX11410_FILTER_RATE_MASK;
if (rate >= max11410_sampling_len[filter])
rate = max11410_sampling_len[filter] - 1;
*val = max11410_sampling_rates[filter][rate][0];
*val2 = max11410_sampling_rates[filter][rate][1];
return IIO_VAL_INT_PLUS_MICRO;
}
return -EINVAL;
}
static int max11410_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct max11410_state *st = iio_priv(indio_dev);
int i, ret, reg_val, filter, gain;
u32 *scale_avail;
switch (mask) {
case IIO_CHAN_INFO_SCALE:
scale_avail = st->channels[chan->address].scale_avail;
if (!scale_avail)
return -EOPNOTSUPP;
/* Accept values in range 0.000001 <= scale < 1.000000 */
if (val != 0 || val2 == 0)
return -EINVAL;
ret = iio_device_claim_direct_mode(indio_dev);
if (ret)
return ret;
/* Convert from INT_PLUS_MICRO to FRACTIONAL_LOG2 */
val2 = val2 * DIV_ROUND_CLOSEST(BIT(24), 1000000);
val2 = DIV_ROUND_CLOSEST(scale_avail[0], val2);
gain = order_base_2(val2);
st->channels[chan->address].gain = clamp_val(gain, 0, 7);
iio_device_release_direct_mode(indio_dev);
return 0;
case IIO_CHAN_INFO_SAMP_FREQ:
ret = iio_device_claim_direct_mode(indio_dev);
if (ret)
return ret;
mutex_lock(&st->lock);
ret = regmap_read(st->regmap, MAX11410_REG_FILTER, ®_val);
if (ret)
goto out;
filter = FIELD_GET(MAX11410_FILTER_LINEF_MASK, reg_val);
for (i = 0; i < max11410_sampling_len[filter]; ++i) {
if (val == max11410_sampling_rates[filter][i][0] &&
val2 == max11410_sampling_rates[filter][i][1])
break;
}
if (i == max11410_sampling_len[filter]) {
ret = -EINVAL;
goto out;
}
ret = regmap_write_bits(st->regmap, MAX11410_REG_FILTER,
MAX11410_FILTER_RATE_MASK, i);
out:
mutex_unlock(&st->lock);
iio_device_release_direct_mode(indio_dev);
return ret;
default:
return -EINVAL;
}
}
static int max11410_read_avail(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
const int **vals, int *type, int *length,
long info)
{
struct max11410_state *st = iio_priv(indio_dev);
struct max11410_channel_config cfg;
int ret, reg_val, filter;
switch (info) {
case IIO_CHAN_INFO_SAMP_FREQ:
ret = regmap_read(st->regmap, MAX11410_REG_FILTER, ®_val);
if (ret)
return ret;
filter = FIELD_GET(MAX11410_FILTER_LINEF_MASK, reg_val);
*vals = (const int *)max11410_sampling_rates[filter];
*length = max11410_sampling_len[filter] * 2;
*type = IIO_VAL_INT_PLUS_MICRO;
return IIO_AVAIL_LIST;
case IIO_CHAN_INFO_SCALE:
cfg = st->channels[chan->address];
if (!cfg.scale_avail)
return -EINVAL;
*vals = cfg.scale_avail;
*length = MAX11410_SCALE_AVAIL_SIZE * 2;
*type = IIO_VAL_FRACTIONAL_LOG2;
return IIO_AVAIL_LIST;
}
return -EINVAL;
}
static const struct iio_info max11410_info = {
.read_raw = max11410_read_raw,
.write_raw = max11410_write_raw,
.read_avail = max11410_read_avail,
.attrs = &max11410_attribute_group,
};
static irqreturn_t max11410_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct max11410_state *st = iio_priv(indio_dev);
int ret;
ret = max11410_read_reg(st, MAX11410_REG_DATA0, &st->scan.data);
if (ret) {
dev_err(&indio_dev->dev, "cannot read data\n");
goto out;
}
iio_push_to_buffers_with_timestamp(indio_dev, &st->scan,
iio_get_time_ns(indio_dev));
out:
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static int max11410_buffer_postenable(struct iio_dev *indio_dev)
{
struct max11410_state *st = iio_priv(indio_dev);
int scan_ch, ret;
scan_ch = ffs(*indio_dev->active_scan_mask) - 1;
ret = max11410_configure_channel(st, &indio_dev->channels[scan_ch]);
if (ret)
return ret;
/* Start continuous conversion. */
return max11410_write_reg(st, MAX11410_REG_CONV_START,
MAX11410_CONV_TYPE_CONTINUOUS);
}
static int max11410_buffer_predisable(struct iio_dev *indio_dev)
{
struct max11410_state *st = iio_priv(indio_dev);
/* Stop continuous conversion. */
return max11410_write_reg(st, MAX11410_REG_CONV_START,
MAX11410_CONV_TYPE_SINGLE);
}
static const struct iio_buffer_setup_ops max11410_buffer_ops = {
.postenable = &max11410_buffer_postenable,
.predisable = &max11410_buffer_predisable,
.validate_scan_mask = &iio_validate_scan_mask_onehot,
};
static const struct iio_trigger_ops max11410_trigger_ops = {
.validate_device = iio_trigger_validate_own_device,
};
static irqreturn_t max11410_interrupt(int irq, void *dev_id)
{
struct iio_dev *indio_dev = dev_id;
struct max11410_state *st = iio_priv(indio_dev);
if (iio_buffer_enabled(indio_dev))
iio_trigger_poll_nested(st->trig);
else
complete(&st->completion);
return IRQ_HANDLED;
};
static int max11410_parse_channels(struct max11410_state *st,
struct iio_dev *indio_dev)
{
struct iio_chan_spec chanspec = chanspec_template;
struct device *dev = &st->spi_dev->dev;
struct max11410_channel_config *cfg;
struct iio_chan_spec *channels;
u32 reference, sig_path;
const char *node_name;
u32 inputs[2], scale;
unsigned int num_ch;
int chan_idx = 0;
int ret, i;
num_ch = device_get_child_node_count(dev);
if (num_ch == 0)
return dev_err_probe(&indio_dev->dev, -ENODEV,
"FW has no channels defined\n");
/* Reserve space for soft timestamp channel */
num_ch++;
channels = devm_kcalloc(dev, num_ch, sizeof(*channels), GFP_KERNEL);
if (!channels)
return -ENOMEM;
st->channels = devm_kcalloc(dev, num_ch, sizeof(*st->channels),
GFP_KERNEL);
if (!st->channels)
return -ENOMEM;
device_for_each_child_node_scoped(dev, child) {
node_name = fwnode_get_name(child);
if (fwnode_property_present(child, "diff-channels")) {
ret = fwnode_property_read_u32_array(child,
"diff-channels",
inputs,
ARRAY_SIZE(inputs));
chanspec.differential = 1;
} else {
ret = fwnode_property_read_u32(child, "reg", &inputs[0]);
inputs[1] = 0;
chanspec.differential = 0;
}
if (ret)
return ret;
if (inputs[0] > MAX11410_CHANNEL_INDEX_MAX ||
inputs[1] > MAX11410_CHANNEL_INDEX_MAX)
return dev_err_probe(&indio_dev->dev, -EINVAL,
"Invalid channel index for %s, should be less than %d\n",
node_name,
MAX11410_CHANNEL_INDEX_MAX + 1);
cfg = &st->channels[chan_idx];
reference = MAX11410_REFSEL_AVDD_AGND;
fwnode_property_read_u32(child, "adi,reference", &reference);
if (reference > MAX11410_REFSEL_MAX)
return dev_err_probe(&indio_dev->dev, -EINVAL,
"Invalid adi,reference value for %s, should be less than %d.\n",
node_name, MAX11410_REFSEL_MAX + 1);
if (!max11410_get_vrefp(st, reference) ||
(!max11410_get_vrefn(st, reference) && reference <= 2))
return dev_err_probe(&indio_dev->dev, -EINVAL,
"Invalid VREF configuration for %s, either specify corresponding VREF regulators or change adi,reference property.\n",
node_name);
sig_path = MAX11410_PGA_SIG_PATH_BUFFERED;
fwnode_property_read_u32(child, "adi,input-mode", &sig_path);
if (sig_path > MAX11410_SIG_PATH_MAX)
return dev_err_probe(&indio_dev->dev, -EINVAL,
"Invalid adi,input-mode value for %s, should be less than %d.\n",
node_name, MAX11410_SIG_PATH_MAX + 1);
fwnode_property_read_u32(child, "settling-time-us",
&cfg->settling_time_us);
cfg->bipolar = fwnode_property_read_bool(child, "bipolar");
cfg->buffered_vrefp = fwnode_property_read_bool(child, "adi,buffered-vrefp");
cfg->buffered_vrefn = fwnode_property_read_bool(child, "adi,buffered-vrefn");
cfg->refsel = reference;
cfg->sig_path = sig_path;
cfg->gain = 0;
/* Enable scale_available property if input mode is PGA */
if (sig_path == MAX11410_PGA_SIG_PATH_PGA) {
__set_bit(IIO_CHAN_INFO_SCALE,
&chanspec.info_mask_separate_available);
cfg->scale_avail = devm_kcalloc(dev, MAX11410_SCALE_AVAIL_SIZE * 2,
sizeof(*cfg->scale_avail),
GFP_KERNEL);
if (!cfg->scale_avail)
return -ENOMEM;
scale = max11410_get_scale(st, *cfg);
for (i = 0; i < MAX11410_SCALE_AVAIL_SIZE; i++) {
cfg->scale_avail[2 * i] = scale >> i;
cfg->scale_avail[2 * i + 1] = chanspec.scan_type.realbits;
}
} else {
__clear_bit(IIO_CHAN_INFO_SCALE,
&chanspec.info_mask_separate_available);
}
chanspec.address = chan_idx;
chanspec.scan_index = chan_idx;
chanspec.channel = inputs[0];
chanspec.channel2 = inputs[1];
channels[chan_idx] = chanspec;
chan_idx++;
}
channels[chan_idx] = (struct iio_chan_spec)IIO_CHAN_SOFT_TIMESTAMP(chan_idx);
indio_dev->num_channels = chan_idx + 1;
indio_dev->channels = channels;
return 0;
}
static void max11410_disable_reg(void *reg)
{
regulator_disable(reg);
}
static int max11410_init_vref(struct device *dev,
struct regulator **vref,
const char *id)
{
struct regulator *reg;
int ret;
reg = devm_regulator_get_optional(dev, id);
if (PTR_ERR(reg) == -ENODEV) {
*vref = NULL;
return 0;
} else if (IS_ERR(reg)) {
return PTR_ERR(reg);
}
ret = regulator_enable(reg);
if (ret)
return dev_err_probe(dev, ret,
"Failed to enable regulator %s\n", id);
*vref = reg;
return devm_add_action_or_reset(dev, max11410_disable_reg, reg);
}
static int max11410_calibrate(struct max11410_state *st, u32 cal_type)
{
int ret, ret2, val;
ret = max11410_write_reg(st, MAX11410_REG_CAL_START, cal_type);
if (ret)
return ret;
/* Wait for status register Calibration Ready flag */
ret = read_poll_timeout(max11410_read_reg, ret2,
ret2 || (val & MAX11410_STATUS_CAL_READY_BIT),
50000, MAX11410_CALIB_TIMEOUT_MS * 1000, true,
st, MAX11410_REG_STATUS, &val);
if (ret)
return ret;
return ret2;
}
static int max11410_self_calibrate(struct max11410_state *st)
{
int ret, i;
ret = regmap_write_bits(st->regmap, MAX11410_REG_FILTER,
MAX11410_FILTER_RATE_MASK,
FIELD_PREP(MAX11410_FILTER_RATE_MASK,
MAX11410_FILTER_RATE_MAX));
if (ret)
return ret;
ret = max11410_calibrate(st, MAX11410_CAL_START_SELF);
if (ret)
return ret;
ret = regmap_write_bits(st->regmap, MAX11410_REG_PGA,
MAX11410_PGA_SIG_PATH_MASK,
FIELD_PREP(MAX11410_PGA_SIG_PATH_MASK,
MAX11410_PGA_SIG_PATH_PGA));
if (ret)
return ret;
/* PGA calibrations */
for (i = 1; i < 8; ++i) {
ret = regmap_write_bits(st->regmap, MAX11410_REG_PGA,
MAX11410_PGA_GAIN_MASK, i);
if (ret)
return ret;
ret = max11410_calibrate(st, MAX11410_CAL_START_PGA);
if (ret)
return ret;
}
/* Cleanup */
ret = regmap_write_bits(st->regmap, MAX11410_REG_PGA,
MAX11410_PGA_GAIN_MASK, 0);
if (ret)
return ret;
ret = regmap_write_bits(st->regmap, MAX11410_REG_FILTER,
MAX11410_FILTER_RATE_MASK, 0);
if (ret)
return ret;
return regmap_write_bits(st->regmap, MAX11410_REG_PGA,
MAX11410_PGA_SIG_PATH_MASK,
FIELD_PREP(MAX11410_PGA_SIG_PATH_MASK,
MAX11410_PGA_SIG_PATH_BUFFERED));
}
static int max11410_probe(struct spi_device *spi)
{
const char *vrefp_regs[] = { "vref0p", "vref1p", "vref2p" };
const char *vrefn_regs[] = { "vref0n", "vref1n", "vref2n" };
struct device *dev = &spi->dev;
struct max11410_state *st;
struct iio_dev *indio_dev;
int ret, irqs[2];
int i;
indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
if (!indio_dev)
return -ENOMEM;
st = iio_priv(indio_dev);
st->spi_dev = spi;
init_completion(&st->completion);
mutex_init(&st->lock);
indio_dev->name = "max11410";
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->info = &max11410_info;
st->regmap = devm_regmap_init_spi(spi, ®map_config);
if (IS_ERR(st->regmap))
return dev_err_probe(dev, PTR_ERR(st->regmap),
"regmap initialization failed\n");
ret = max11410_init_vref(dev, &st->avdd, "avdd");
if (ret)
return ret;
for (i = 0; i < ARRAY_SIZE(vrefp_regs); i++) {
ret = max11410_init_vref(dev, &st->vrefp[i], vrefp_regs[i]);
if (ret)
return ret;
ret = max11410_init_vref(dev, &st->vrefn[i], vrefn_regs[i]);
if (ret)
return ret;
}
/*
* Regulators must be configured before parsing channels for
* validating "adi,reference" property of each channel.
*/
ret = max11410_parse_channels(st, indio_dev);
if (ret)
return ret;
irqs[0] = fwnode_irq_get_byname(dev_fwnode(dev), "gpio0");
irqs[1] = fwnode_irq_get_byname(dev_fwnode(dev), "gpio1");
if (irqs[0] > 0) {
st->irq = irqs[0];
ret = regmap_write(st->regmap, MAX11410_REG_GPIO_CTRL(0),
MAX11410_GPIO_INTRB);
} else if (irqs[1] > 0) {
st->irq = irqs[1];
ret = regmap_write(st->regmap, MAX11410_REG_GPIO_CTRL(1),
MAX11410_GPIO_INTRB);
} else if (spi->irq > 0) {
return dev_err_probe(dev, -ENODEV,
"no interrupt name specified");
}
if (ret)
return ret;
ret = regmap_set_bits(st->regmap, MAX11410_REG_CTRL,
MAX11410_CTRL_FORMAT_BIT);
if (ret)
return ret;
ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
&max11410_trigger_handler,
&max11410_buffer_ops);
if (ret)
return ret;
if (st->irq > 0) {
st->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
indio_dev->name,
iio_device_id(indio_dev));
if (!st->trig)
return -ENOMEM;
st->trig->ops = &max11410_trigger_ops;
ret = devm_iio_trigger_register(dev, st->trig);
if (ret)
return ret;
ret = devm_request_threaded_irq(dev, st->irq, NULL,
&max11410_interrupt,
IRQF_ONESHOT, "max11410",
indio_dev);
if (ret)
return ret;
}
ret = max11410_self_calibrate(st);
if (ret)
return dev_err_probe(dev, ret,
"cannot perform device self calibration\n");
return devm_iio_device_register(dev, indio_dev);
}
static const struct of_device_id max11410_spi_of_id[] = {
{ .compatible = "adi,max11410" },
{ }
};
MODULE_DEVICE_TABLE(of, max11410_spi_of_id);
static const struct spi_device_id max11410_id[] = {
{ "max11410" },
{ }
};
MODULE_DEVICE_TABLE(spi, max11410_id);
static struct spi_driver max11410_driver = {
.driver = {
.name = "max11410",
.of_match_table = max11410_spi_of_id,
},
.probe = max11410_probe,
.id_table = max11410_id,
};
module_spi_driver(max11410_driver);
MODULE_AUTHOR("David Jung <[email protected]>");
MODULE_AUTHOR("Ibrahim Tilki <[email protected]>");
MODULE_DESCRIPTION("Analog Devices MAX11410 ADC");
MODULE_LICENSE("GPL");
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