afe4403.c
/*
* AFE4403 Heart Rate Monitors and Low-Cost Pulse Oximeters
*
* Copyright (C) 2015-2016 Texas Instruments Incorporated - http://www.ti.com/
* Andrew F. Davis <afd@ti.com>
*
* 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.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*/
#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/spi/spi.h>
#include <linux/sysfs.h>
#include <linux/regulator/consumer.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/buffer.h>
#include <linux/iio/trigger.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/trigger_consumer.h>
#include "afe440x.h"
#define AFE4403_DRIVER_NAME "afe4403"
/* AFE4403 Registers */
#define AFE4403_TIAGAIN 0x20
#define AFE4403_TIA_AMB_GAIN 0x21
enum afe4403_fields {
/* Gains */
F_RF_LED1, F_CF_LED1,
F_RF_LED, F_CF_LED,
/* LED Current */
F_ILED1, F_ILED2,
/* sentinel */
F_MAX_FIELDS
};
static const struct reg_field afe4403_reg_fields[] = {
/* Gains */
[F_RF_LED1] = REG_FIELD(AFE4403_TIAGAIN, 0, 2),
[F_CF_LED1] = REG_FIELD(AFE4403_TIAGAIN, 3, 7),
[F_RF_LED] = REG_FIELD(AFE4403_TIA_AMB_GAIN, 0, 2),
[F_CF_LED] = REG_FIELD(AFE4403_TIA_AMB_GAIN, 3, 7),
/* LED Current */
[F_ILED1] = REG_FIELD(AFE440X_LEDCNTRL, 0, 7),
[F_ILED2] = REG_FIELD(AFE440X_LEDCNTRL, 8, 15),
};
/**
* struct afe4403_data - AFE4403 device instance data
* @dev: Device structure
* @spi: SPI device handle
* @regmap: Register map of the device
* @fields: Register fields of the device
* @regulator: Pointer to the regulator for the IC
* @trig: IIO trigger for this device
* @irq: ADC_RDY line interrupt number
*/
struct afe4403_data {
struct device *dev;
struct spi_device *spi;
struct regmap *regmap;
struct regmap_field *fields[F_MAX_FIELDS];
struct regulator *regulator;
struct iio_trigger *trig;
int irq;
};
enum afe4403_chan_id {
LED2 = 1,
ALED2,
LED1,
ALED1,
LED2_ALED2,
LED1_ALED1,
};
static const unsigned int afe4403_channel_values[] = {
[LED2] = AFE440X_LED2VAL,
[ALED2] = AFE440X_ALED2VAL,
[LED1] = AFE440X_LED1VAL,
[ALED1] = AFE440X_ALED1VAL,
[LED2_ALED2] = AFE440X_LED2_ALED2VAL,
[LED1_ALED1] = AFE440X_LED1_ALED1VAL,
};
static const unsigned int afe4403_channel_leds[] = {
[LED2] = F_ILED2,
[LED1] = F_ILED1,
};
static const struct iio_chan_spec afe4403_channels[] = {
/* ADC values */
AFE440X_INTENSITY_CHAN(LED2, 0),
AFE440X_INTENSITY_CHAN(ALED2, 0),
AFE440X_INTENSITY_CHAN(LED1, 0),
AFE440X_INTENSITY_CHAN(ALED1, 0),
AFE440X_INTENSITY_CHAN(LED2_ALED2, 0),
AFE440X_INTENSITY_CHAN(LED1_ALED1, 0),
/* LED current */
AFE440X_CURRENT_CHAN(LED2),
AFE440X_CURRENT_CHAN(LED1),
};
static const struct afe440x_val_table afe4403_res_table[] = {
{ 500000 }, { 250000 }, { 100000 }, { 50000 },
{ 25000 }, { 10000 }, { 1000000 }, { 0 },
};
AFE440X_TABLE_ATTR(in_intensity_resistance_available, afe4403_res_table);
static const struct afe440x_val_table afe4403_cap_table[] = {
{ 0, 5000 }, { 0, 10000 }, { 0, 20000 }, { 0, 25000 },
{ 0, 30000 }, { 0, 35000 }, { 0, 45000 }, { 0, 50000 },
{ 0, 55000 }, { 0, 60000 }, { 0, 70000 }, { 0, 75000 },
{ 0, 80000 }, { 0, 85000 }, { 0, 95000 }, { 0, 100000 },
{ 0, 155000 }, { 0, 160000 }, { 0, 170000 }, { 0, 175000 },
{ 0, 180000 }, { 0, 185000 }, { 0, 195000 }, { 0, 200000 },
{ 0, 205000 }, { 0, 210000 }, { 0, 220000 }, { 0, 225000 },
{ 0, 230000 }, { 0, 235000 }, { 0, 245000 }, { 0, 250000 },
};
AFE440X_TABLE_ATTR(in_intensity_capacitance_available, afe4403_cap_table);
static ssize_t afe440x_show_register(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct afe4403_data *afe = iio_priv(indio_dev);
struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
unsigned int reg_val;
int vals[2];
int ret;
ret = regmap_field_read(afe->fields[afe440x_attr->field], ®_val);
if (ret)
return ret;
if (reg_val >= afe440x_attr->table_size)
return -EINVAL;
vals[0] = afe440x_attr->val_table[reg_val].integer;
vals[1] = afe440x_attr->val_table[reg_val].fract;
return iio_format_value(buf, IIO_VAL_INT_PLUS_MICRO, 2, vals);
}
static ssize_t afe440x_store_register(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct afe4403_data *afe = iio_priv(indio_dev);
struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
int val, integer, fract, ret;
ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract);
if (ret)
return ret;
for (val = 0; val < afe440x_attr->table_size; val++)
if (afe440x_attr->val_table[val].integer == integer &&
afe440x_attr->val_table[val].fract == fract)
break;
if (val == afe440x_attr->table_size)
return -EINVAL;
ret = regmap_field_write(afe->fields[afe440x_attr->field], val);
if (ret)
return ret;
return count;
}
static AFE440X_ATTR(in_intensity1_resistance, F_RF_LED, afe4403_res_table);
static AFE440X_ATTR(in_intensity1_capacitance, F_CF_LED, afe4403_cap_table);
static AFE440X_ATTR(in_intensity2_resistance, F_RF_LED, afe4403_res_table);
static AFE440X_ATTR(in_intensity2_capacitance, F_CF_LED, afe4403_cap_table);
static AFE440X_ATTR(in_intensity3_resistance, F_RF_LED1, afe4403_res_table);
static AFE440X_ATTR(in_intensity3_capacitance, F_CF_LED1, afe4403_cap_table);
static AFE440X_ATTR(in_intensity4_resistance, F_RF_LED1, afe4403_res_table);
static AFE440X_ATTR(in_intensity4_capacitance, F_CF_LED1, afe4403_cap_table);
static struct attribute *afe440x_attributes[] = {
&dev_attr_in_intensity_resistance_available.attr,
&dev_attr_in_intensity_capacitance_available.attr,
&afe440x_attr_in_intensity1_resistance.dev_attr.attr,
&afe440x_attr_in_intensity1_capacitance.dev_attr.attr,
&afe440x_attr_in_intensity2_resistance.dev_attr.attr,
&afe440x_attr_in_intensity2_capacitance.dev_attr.attr,
&afe440x_attr_in_intensity3_resistance.dev_attr.attr,
&afe440x_attr_in_intensity3_capacitance.dev_attr.attr,
&afe440x_attr_in_intensity4_resistance.dev_attr.attr,
&afe440x_attr_in_intensity4_capacitance.dev_attr.attr,
NULL
};
static const struct attribute_group afe440x_attribute_group = {
.attrs = afe440x_attributes
};
static int afe4403_read(struct afe4403_data *afe, unsigned int reg, u32 *val)
{
u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ};
u8 rx[3];
int ret;
/* Enable reading from the device */
ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
if (ret)
return ret;
ret = spi_write_then_read(afe->spi, ®, 1, rx, 3);
if (ret)
return ret;
*val = (rx[0] << 16) |
(rx[1] << 8) |
(rx[2]);
/* Disable reading from the device */
tx[3] = AFE440X_CONTROL0_WRITE;
ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
if (ret)
return ret;
return 0;
}
static int afe4403_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct afe4403_data *afe = iio_priv(indio_dev);
unsigned int reg = afe4403_channel_values[chan->address];
unsigned int field = afe4403_channel_leds[chan->address];
int ret;
switch (chan->type) {
case IIO_INTENSITY:
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = afe4403_read(afe, reg, val);
if (ret)
return ret;
return IIO_VAL_INT;
}
break;
case IIO_CURRENT:
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = regmap_field_read(afe->fields[field], val);
if (ret)
return ret;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
*val = 0;
*val2 = 800000;
return IIO_VAL_INT_PLUS_MICRO;
}
break;
default:
break;
}
return -EINVAL;
}
static int afe4403_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct afe4403_data *afe = iio_priv(indio_dev);
unsigned int field = afe4403_channel_leds[chan->address];
switch (chan->type) {
case IIO_CURRENT:
switch (mask) {
case IIO_CHAN_INFO_RAW:
return regmap_field_write(afe->fields[field], val);
}
break;
default:
break;
}
return -EINVAL;
}
static const struct iio_info afe4403_iio_info = {
.attrs = &afe440x_attribute_group,
.read_raw = afe4403_read_raw,
.write_raw = afe4403_write_raw,
.driver_module = THIS_MODULE,
};
static irqreturn_t afe4403_trigger_handler(int irq, void *private)
{
struct iio_poll_func *pf = private;
struct iio_dev *indio_dev = pf->indio_dev;
struct afe4403_data *afe = iio_priv(indio_dev);
int ret, bit, i = 0;
s32 buffer[8];
u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ};
u8 rx[3];
/* Enable reading from the device */
ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
if (ret)
goto err;
for_each_set_bit(bit, indio_dev->active_scan_mask,
indio_dev->masklength) {
ret = spi_write_then_read(afe->spi,
&afe4403_channel_values[bit], 1,
rx, 3);
if (ret)
goto err;
buffer[i++] = (rx[0] << 16) |
(rx[1] << 8) |
(rx[2]);
}
/* Disable reading from the device */
tx[3] = AFE440X_CONTROL0_WRITE;
ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
if (ret)
goto err;
iio_push_to_buffers_with_timestamp(indio_dev, buffer, pf->timestamp);
err:
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static const struct iio_trigger_ops afe4403_trigger_ops = {
.owner = THIS_MODULE,
};
#define AFE4403_TIMING_PAIRS \
{ AFE440X_LED2STC, 0x000050 }, \
{ AFE440X_LED2ENDC, 0x0003e7 }, \
{ AFE440X_LED1LEDSTC, 0x0007d0 }, \
{ AFE440X_LED1LEDENDC, 0x000bb7 }, \
{ AFE440X_ALED2STC, 0x000438 }, \
{ AFE440X_ALED2ENDC, 0x0007cf }, \
{ AFE440X_LED1STC, 0x000820 }, \
{ AFE440X_LED1ENDC, 0x000bb7 }, \
{ AFE440X_LED2LEDSTC, 0x000000 }, \
{ AFE440X_LED2LEDENDC, 0x0003e7 }, \
{ AFE440X_ALED1STC, 0x000c08 }, \
{ AFE440X_ALED1ENDC, 0x000f9f }, \
{ AFE440X_LED2CONVST, 0x0003ef }, \
{ AFE440X_LED2CONVEND, 0x0007cf }, \
{ AFE440X_ALED2CONVST, 0x0007d7 }, \
{ AFE440X_ALED2CONVEND, 0x000bb7 }, \
{ AFE440X_LED1CONVST, 0x000bbf }, \
{ AFE440X_LED1CONVEND, 0x009c3f }, \
{ AFE440X_ALED1CONVST, 0x000fa7 }, \
{ AFE440X_ALED1CONVEND, 0x001387 }, \
{ AFE440X_ADCRSTSTCT0, 0x0003e8 }, \
{ AFE440X_ADCRSTENDCT0, 0x0003eb }, \
{ AFE440X_ADCRSTSTCT1, 0x0007d0 }, \
{ AFE440X_ADCRSTENDCT1, 0x0007d3 }, \
{ AFE440X_ADCRSTSTCT2, 0x000bb8 }, \
{ AFE440X_ADCRSTENDCT2, 0x000bbb }, \
{ AFE440X_ADCRSTSTCT3, 0x000fa0 }, \
{ AFE440X_ADCRSTENDCT3, 0x000fa3 }, \
{ AFE440X_PRPCOUNT, 0x009c3f }, \
{ AFE440X_PDNCYCLESTC, 0x001518 }, \
{ AFE440X_PDNCYCLEENDC, 0x00991f }
static const struct reg_sequence afe4403_reg_sequences[] = {
AFE4403_TIMING_PAIRS,
{ AFE440X_CONTROL1, AFE440X_CONTROL1_TIMEREN },
{ AFE4403_TIAGAIN, AFE440X_TIAGAIN_ENSEPGAIN },
};
static const struct regmap_range afe4403_yes_ranges[] = {
regmap_reg_range(AFE440X_LED2VAL, AFE440X_LED1_ALED1VAL),
};
static const struct regmap_access_table afe4403_volatile_table = {
.yes_ranges = afe4403_yes_ranges,
.n_yes_ranges = ARRAY_SIZE(afe4403_yes_ranges),
};
static const struct regmap_config afe4403_regmap_config = {
.reg_bits = 8,
.val_bits = 24,
.max_register = AFE440X_PDNCYCLEENDC,
.cache_type = REGCACHE_RBTREE,
.volatile_table = &afe4403_volatile_table,
};
static const struct of_device_id afe4403_of_match[] = {
{ .compatible = "ti,afe4403", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, afe4403_of_match);
static int __maybe_unused afe4403_suspend(struct device *dev)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct afe4403_data *afe = iio_priv(indio_dev);
int ret;
ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
AFE440X_CONTROL2_PDN_AFE,
AFE440X_CONTROL2_PDN_AFE);
if (ret)
return ret;
ret = regulator_disable(afe->regulator);
if (ret) {
dev_err(dev, "Unable to disable regulator\n");
return ret;
}
return 0;
}
static int __maybe_unused afe4403_resume(struct device *dev)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct afe4403_data *afe = iio_priv(indio_dev);
int ret;
ret = regulator_enable(afe->regulator);
if (ret) {
dev_err(dev, "Unable to enable regulator\n");
return ret;
}
ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
AFE440X_CONTROL2_PDN_AFE, 0);
if (ret)
return ret;
return 0;
}
static SIMPLE_DEV_PM_OPS(afe4403_pm_ops, afe4403_suspend, afe4403_resume);
static int afe4403_probe(struct spi_device *spi)
{
struct iio_dev *indio_dev;
struct afe4403_data *afe;
int i, ret;
indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*afe));
if (!indio_dev)
return -ENOMEM;
afe = iio_priv(indio_dev);
spi_set_drvdata(spi, indio_dev);
afe->dev = &spi->dev;
afe->spi = spi;
afe->irq = spi->irq;
afe->regmap = devm_regmap_init_spi(spi, &afe4403_regmap_config);
if (IS_ERR(afe->regmap)) {
dev_err(afe->dev, "Unable to allocate register map\n");
return PTR_ERR(afe->regmap);
}
for (i = 0; i < F_MAX_FIELDS; i++) {
afe->fields[i] = devm_regmap_field_alloc(afe->dev, afe->regmap,
afe4403_reg_fields[i]);
if (IS_ERR(afe->fields[i])) {
dev_err(afe->dev, "Unable to allocate regmap fields\n");
return PTR_ERR(afe->fields[i]);
}
}
afe->regulator = devm_regulator_get(afe->dev, "tx_sup");
if (IS_ERR(afe->regulator)) {
dev_err(afe->dev, "Unable to get regulator\n");
return PTR_ERR(afe->regulator);
}
ret = regulator_enable(afe->regulator);
if (ret) {
dev_err(afe->dev, "Unable to enable regulator\n");
return ret;
}
ret = regmap_write(afe->regmap, AFE440X_CONTROL0,
AFE440X_CONTROL0_SW_RESET);
if (ret) {
dev_err(afe->dev, "Unable to reset device\n");
goto err_disable_reg;
}
ret = regmap_multi_reg_write(afe->regmap, afe4403_reg_sequences,
ARRAY_SIZE(afe4403_reg_sequences));
if (ret) {
dev_err(afe->dev, "Unable to set register defaults\n");
goto err_disable_reg;
}
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->dev.parent = afe->dev;
indio_dev->channels = afe4403_channels;
indio_dev->num_channels = ARRAY_SIZE(afe4403_channels);
indio_dev->name = AFE4403_DRIVER_NAME;
indio_dev->info = &afe4403_iio_info;
if (afe->irq > 0) {
afe->trig = devm_iio_trigger_alloc(afe->dev,
"%s-dev%d",
indio_dev->name,
indio_dev->id);
if (!afe->trig) {
dev_err(afe->dev, "Unable to allocate IIO trigger\n");
ret = -ENOMEM;
goto err_disable_reg;
}
iio_trigger_set_drvdata(afe->trig, indio_dev);
afe->trig->ops = &afe4403_trigger_ops;
afe->trig->dev.parent = afe->dev;
ret = iio_trigger_register(afe->trig);
if (ret) {
dev_err(afe->dev, "Unable to register IIO trigger\n");
goto err_disable_reg;
}
ret = devm_request_threaded_irq(afe->dev, afe->irq,
iio_trigger_generic_data_rdy_poll,
NULL, IRQF_ONESHOT,
AFE4403_DRIVER_NAME,
afe->trig);
if (ret) {
dev_err(afe->dev, "Unable to request IRQ\n");
goto err_trig;
}
}
ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
afe4403_trigger_handler, NULL);
if (ret) {
dev_err(afe->dev, "Unable to setup buffer\n");
goto err_trig;
}
ret = iio_device_register(indio_dev);
if (ret) {
dev_err(afe->dev, "Unable to register IIO device\n");
goto err_buff;
}
return 0;
err_buff:
iio_triggered_buffer_cleanup(indio_dev);
err_trig:
if (afe->irq > 0)
iio_trigger_unregister(afe->trig);
err_disable_reg:
regulator_disable(afe->regulator);
return ret;
}
static int afe4403_remove(struct spi_device *spi)
{
struct iio_dev *indio_dev = spi_get_drvdata(spi);
struct afe4403_data *afe = iio_priv(indio_dev);
int ret;
iio_device_unregister(indio_dev);
iio_triggered_buffer_cleanup(indio_dev);
if (afe->irq > 0)
iio_trigger_unregister(afe->trig);
ret = regulator_disable(afe->regulator);
if (ret) {
dev_err(afe->dev, "Unable to disable regulator\n");
return ret;
}
return 0;
}
static const struct spi_device_id afe4403_ids[] = {
{ "afe4403", 0 },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(spi, afe4403_ids);
static struct spi_driver afe4403_spi_driver = {
.driver = {
.name = AFE4403_DRIVER_NAME,
.of_match_table = afe4403_of_match,
.pm = &afe4403_pm_ops,
},
.probe = afe4403_probe,
.remove = afe4403_remove,
.id_table = afe4403_ids,
};
module_spi_driver(afe4403_spi_driver);
MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
MODULE_DESCRIPTION("TI AFE4403 Heart Rate Monitor and Pulse Oximeter AFE");
MODULE_LICENSE("GPL v2");