[PATCH v2 2/2] iio: adc: ti-ads1119: Add driver
From: Francesco Dolcini
Date: Thu Jun 06 2024 - 12:36:13 EST
From: João Paulo Gonçalves <joao.goncalves@xxxxxxxxxxx>
The ADS1119 is a precision, 16-bit, analog-to-digital converter (ADC)
that features two differential or four single-ended inputs through a
flexible input multiplexer (MUX), rail-to-rail input
buffers, a programmable gain stage, a voltage reference, and an
oscillator.
Apart from normal single conversion, the driver also supports
continuous conversion mode using a triggered buffer. However, in this
mode only one channel can be scanned at a time, and it only uses the data
ready interrupt as a trigger. This is because the device channels are
multiplexed, and using its own data ready interrupt as a trigger guarantees
the signal sampling frequency.
Datasheet: https://www.ti.com/lit/gpn/ads1119
Signed-off-by: João Paulo Gonçalves <joao.goncalves@xxxxxxxxxxx>
Signed-off-by: Francesco Dolcini <francesco.dolcini@xxxxxxxxxxx>
---
v2:
- add 2 functions to wr/rd regs values: ads1119_update_config_reg and ads1119_data_ready
- add FIELD(PREP, GET) for bitmasks
- add driver string inline
- add devm_regulator_get_enable_read_voltage to handle external vref
- add comment for resume function
- add userspace configuration of gain/datarate
- changed bitmasks names to FIELD suffix
- changed channel allocation to handle diff-channels/single-channel
- changed single conversion to power down on error
- changed to create scan masks dynamically to avoid warnings
- fix ret=0 in ads1119_read_data()
- fix irq trigger handler error handling order
- removed regmap from code and KCONFIG
- removed of_match_ptr()
- removed ads1119_get_configs() and put inlined on probe
- removed static allocation of iio channels
- removed ads1119_set_power() and called it inline on necessary places
- removed not necessary bitmasks and macros
- removed match data struct
- removed set mux/gain/datarate functions and called them inline
---
MAINTAINERS | 1 +
drivers/iio/adc/Kconfig | 12 +
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/ti-ads1119.c | 850 +++++++++++++++++++++++++++++++++++
4 files changed, 864 insertions(+)
create mode 100644 drivers/iio/adc/ti-ads1119.c
diff --git a/MAINTAINERS b/MAINTAINERS
index f1b2c4b815e2..ab9febe5dc9c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -22386,6 +22386,7 @@ M: João Paulo Gonçalves <jpaulo.silvagoncalves@xxxxxxxxx>
L: linux-iio@xxxxxxxxxxxxxxx
S: Maintained
F: Documentation/devicetree/bindings/iio/adc/ti,ads1119.yaml
+F: drivers/iio/adc/ti-ads1119.c
TI ADS7924 ADC DRIVER
M: Hugo Villeneuve <hvilleneuve@xxxxxxxxxxxx>
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 74fecc284f1a..3022b1ac93a0 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -1334,6 +1334,18 @@ config TI_ADS1015
This driver can also be built as a module. If so, the module will be
called ti-ads1015.
+config TI_ADS1119
+ tristate "Texas Instruments ADS1119 ADC"
+ depends on I2C
+ select IIO_BUFFER
+ select IIO_TRIGGERED_BUFFER
+ help
+ If you say yes here you get support for Texas Instruments ADS1119
+ ADC chip.
+
+ This driver can also be built as a module. If so, the module will be
+ called ti-ads1119.
+
config TI_ADS7924
tristate "Texas Instruments ADS7924 ADC"
depends on I2C
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 6a8c2da0e707..50cde66790cf 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -120,6 +120,7 @@ obj-$(CONFIG_TI_ADC128S052) += ti-adc128s052.o
obj-$(CONFIG_TI_ADC161S626) += ti-adc161s626.o
obj-$(CONFIG_TI_ADS1015) += ti-ads1015.o
obj-$(CONFIG_TI_ADS1100) += ti-ads1100.o
+obj-$(CONFIG_TI_ADS1119) += ti-ads1119.o
obj-$(CONFIG_TI_ADS124S08) += ti-ads124s08.o
obj-$(CONFIG_TI_ADS1298) += ti-ads1298.o
obj-$(CONFIG_TI_ADS131E08) += ti-ads131e08.o
diff --git a/drivers/iio/adc/ti-ads1119.c b/drivers/iio/adc/ti-ads1119.c
new file mode 100644
index 000000000000..ea0573f07279
--- /dev/null
+++ b/drivers/iio/adc/ti-ads1119.c
@@ -0,0 +1,850 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Texas Instruments ADS1119 ADC driver.
+ *
+ * Copyright 2024 Toradex
+ */
+
+#include <linux/bits.h>
+#include <linux/bitfield.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/dev_printk.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/iopoll.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/math.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+
+#define ADS1119_CMD_RESET 0x06
+#define ADS1119_CMD_POWERDOWN 0x02
+#define ADS1119_CMD_START_SYNC 0x08
+#define ADS1119_CMD_RDATA 0x10
+#define ADS1119_CMD_RREG(reg) (0x20 | ((reg) << 2))
+#define ADS1119_CMD_WREG 0x40
+
+/* Config register */
+#define ADS1119_REG_CONFIG 0x00
+#define ADS1119_CONFIG_VREF_FIELD BIT(0)
+#define ADS1119_CONFIG_CM_FIELD BIT(1)
+#define ADS1119_CONFIG_DR_FIELD GENMASK(3, 2)
+#define ADS1119_CONFIG_GAIN_FIELD BIT(4)
+#define ADS1119_CONFIG_MUX_FIELD GENMASK(7, 5)
+
+#define ADS1119_VREF_INTERNAL 0
+#define ADS1119_VREF_EXTERNAL 1
+#define ADS1119_VREF_INTERNAL_VAL 2048000
+
+#define ADS1119_CM_SINGLE 0
+#define ADS1119_CM_CONTINUOUS 1
+
+#define ADS1119_DR_20_SPS 0
+#define ADS1119_DR_90_SPS 1
+#define ADS1119_DR_330_SPS 2
+#define ADS1119_DR_1000_SPS 3
+
+#define ADS1119_GAIN_1 0
+#define ADS1119_GAIN_4 1
+
+#define ADS1119_MUX_AIN0_AIN1 0
+#define ADS1119_MUX_AIN2_AIN3 1
+#define ADS1119_MUX_AIN1_AIN2 2
+#define ADS1119_MUX_AIN0 3
+#define ADS1119_MUX_AIN1 4
+#define ADS1119_MUX_AIN2 5
+#define ADS1119_MUX_AIN3 6
+#define ADS1119_MUX_SHORTED 7
+
+/* Status register */
+#define ADS1119_REG_STATUS 0x01
+#define ADS1119_STATUS_DRDY_FIELD BIT(7)
+
+#define ADS1119_DEFAULT_GAIN 1
+#define ADS1119_DEFAULT_DATARATE 20
+
+#define ADS1119_SUSPEND_DELAY 2000
+
+/* Timeout based on the minimum sample rate of 20 SPS (50000us) */
+#define ADS1119_MAX_DRDY_TIMEOUT 85000
+
+/*
+ * Static allocate buffer for scans assuming one channel sample (2 or 4 bytes)
+ * + _aligned(8) timestamp (8 bytes).
+ */
+#define ADS1119_SCAN_BUFFER_SIZE 16
+
+#define ADS1119_MAX_CHANNELS 7
+#define ADS1119_MAX_SINGLE_CHANNELS 4
+
+#define ADS1119_V_CHAN(_chan, _chan2, _addr) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .address = _addr, \
+ .channel = _chan, \
+ .channel2 = _chan2, \
+ .info_mask_separate = \
+ BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE) | \
+ BIT(IIO_CHAN_INFO_OFFSET) | \
+ BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .info_mask_shared_by_all_available = \
+ BIT(IIO_CHAN_INFO_SCALE) | \
+ BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .scan_index = _addr, \
+ .scan_type = { \
+ .sign = 's', \
+ .realbits = 16, \
+ .storagebits = 16, \
+ .endianness = IIO_CPU, \
+ }, \
+}
+
+struct ads1119_channel_config {
+ int gain;
+ int datarate;
+ int mux;
+};
+
+struct ads1119_state {
+ unsigned long scan_masks[ADS1119_MAX_CHANNELS + 1];
+ u8 scan_buf[ADS1119_SCAN_BUFFER_SIZE];
+ struct completion completion;
+ struct i2c_client *client;
+ struct gpio_desc *reset_gpio;
+ struct iio_trigger *trig;
+ struct ads1119_channel_config *channels_cfg;
+ unsigned int num_bytes_sample;
+ unsigned int num_channels_cfg;
+ int vref_uV;
+};
+
+static const int ads1119_available_datarates[] = {
+ 20, 90, 330, 1000,
+};
+
+static const int ads1119_available_gains[] = {
+ 1, 1,
+ 1, 4,
+};
+
+static int ads1119_cmd(struct ads1119_state *st, unsigned int cmd)
+{
+ dev_dbg(&st->client->dev, "cmd: %#x\n", cmd);
+
+ return i2c_smbus_write_byte(st->client, cmd);
+}
+
+static int ads1119_cmd_wreg(struct ads1119_state *st, unsigned int val)
+{
+ dev_dbg(&st->client->dev, "wreg: %#x\n", val);
+
+ return i2c_smbus_write_byte_data(st->client, ADS1119_CMD_WREG, val);
+}
+
+static int ads1119_cmd_rreg(struct ads1119_state *st, unsigned int reg,
+ unsigned int *val)
+{
+ int ret;
+
+ ret = i2c_smbus_read_byte_data(st->client, ADS1119_CMD_RREG(reg));
+ if (ret < 0)
+ return ret;
+
+ dev_dbg(&st->client->dev, "rreg %#x: %#x\n", reg, ret);
+
+ *val = ret;
+
+ return 0;
+}
+
+static int ads1119_cmd_rdata(struct ads1119_state *st, unsigned int *val)
+{
+ int ret;
+
+ ret = i2c_smbus_read_word_swapped(st->client, ADS1119_CMD_RDATA);
+ if (ret < 0)
+ return ret;
+
+ dev_dbg(&st->client->dev, "rdata: %#x\n", ret);
+
+ *val = ret;
+
+ return 0;
+}
+
+static int ads1119_update_config_reg(struct ads1119_state *st,
+ unsigned int fields,
+ unsigned int val)
+{
+ unsigned int config;
+ int ret;
+
+ ret = ads1119_cmd_rreg(st, ADS1119_REG_CONFIG, &config);
+ if (ret)
+ return ret;
+
+ config &= ~fields;
+ config |= val;
+
+ return ads1119_cmd_wreg(st, config);
+}
+
+static bool ads1119_data_ready(struct ads1119_state *st)
+{
+ unsigned int status;
+
+ if (!ads1119_cmd_rreg(st, ADS1119_REG_STATUS, &status))
+ return FIELD_GET(ADS1119_STATUS_DRDY_FIELD, status);
+
+ return 0;
+}
+
+static int ads1119_reset(struct ads1119_state *st)
+{
+ if (!st->reset_gpio)
+ return ads1119_cmd(st, ADS1119_CMD_RESET);
+
+ gpiod_set_value_cansleep(st->reset_gpio, 1);
+ udelay(1);
+ gpiod_set_value_cansleep(st->reset_gpio, 0);
+ udelay(1);
+
+ return 0;
+}
+
+static int ads1119_set_conv_mode(struct ads1119_state *st, bool continuous)
+{
+ unsigned int mode;
+
+ if (continuous)
+ mode = ADS1119_CM_CONTINUOUS;
+ else
+ mode = ADS1119_CM_SINGLE;
+
+ return ads1119_update_config_reg(st,
+ ADS1119_CONFIG_CM_FIELD,
+ FIELD_PREP(ADS1119_CONFIG_CM_FIELD, mode));
+}
+
+static int ads1119_get_hw_gain(int gain)
+{
+ if (gain == 4)
+ return ADS1119_GAIN_4;
+ else
+ return ADS1119_GAIN_1;
+}
+
+static int ads1119_get_hw_datarate(int datarate)
+{
+ switch (datarate) {
+ case 90:
+ datarate = ADS1119_DR_90_SPS;
+ break;
+ case 330:
+ datarate = ADS1119_DR_330_SPS;
+ break;
+ case 1000:
+ datarate = ADS1119_DR_1000_SPS;
+ break;
+ case 20:
+ default:
+ datarate = ADS1119_DR_20_SPS;
+ break;
+ }
+
+ return datarate;
+}
+
+static int ads1119_configure_channel(struct ads1119_state *st, int mux,
+ int gain, int datarate)
+{
+ int ret;
+
+ ret = ads1119_update_config_reg(st,
+ ADS1119_CONFIG_MUX_FIELD,
+ FIELD_PREP(ADS1119_CONFIG_MUX_FIELD, mux));
+ if (ret)
+ return ret;
+
+ ret = ads1119_update_config_reg(st,
+ ADS1119_CONFIG_GAIN_FIELD,
+ FIELD_PREP(ADS1119_CONFIG_GAIN_FIELD,
+ ads1119_get_hw_gain(gain)));
+ if (ret)
+ return ret;
+
+ return ads1119_update_config_reg(st,
+ ADS1119_CONFIG_DR_FIELD,
+ FIELD_PREP(ADS1119_CONFIG_DR_FIELD,
+ ads1119_get_hw_datarate(datarate)));
+}
+
+static int ads1119_poll_data_ready(struct ads1119_state *st,
+ struct iio_chan_spec const *chan)
+{
+ unsigned int datarate = st->channels_cfg[chan->address].datarate;
+ unsigned long wait_time;
+ bool data_ready;
+
+ /* Sleep between poll half of the data rate */
+ wait_time = DIV_ROUND_CLOSEST(1000000, 2 * datarate);
+
+ return read_poll_timeout(ads1119_data_ready,
+ data_ready,
+ (data_ready == true),
+ wait_time,
+ ADS1119_MAX_DRDY_TIMEOUT,
+ false,
+ st);
+}
+
+static int ads1119_read_data(struct ads1119_state *st,
+ struct iio_chan_spec const *chan,
+ unsigned int *val)
+{
+ unsigned int timeout;
+ int ret = 0;
+
+ timeout = msecs_to_jiffies(ADS1119_MAX_DRDY_TIMEOUT);
+
+ if (!st->client->irq)
+ ret = ads1119_poll_data_ready(st, chan);
+ else if (!wait_for_completion_timeout(&st->completion, timeout))
+ ret = -ETIMEDOUT;
+
+ if (ret)
+ return ret;
+
+ return ads1119_cmd_rdata(st, val);
+}
+
+static int ads1119_single_conversion(struct ads1119_state *st,
+ struct iio_chan_spec const *chan,
+ int *val,
+ bool calib_offset)
+{
+ struct device *dev = &st->client->dev;
+ int mux, gain, datarate;
+ unsigned int sample;
+ int ret;
+
+ mux = st->channels_cfg[chan->address].mux;
+ gain = st->channels_cfg[chan->address].gain;
+ datarate = st->channels_cfg[chan->address].datarate;
+
+ if (calib_offset)
+ mux = ADS1119_MUX_SHORTED;
+
+ ret = pm_runtime_resume_and_get(dev);
+ if (ret)
+ goto end;
+
+ ret = ads1119_configure_channel(st, mux, gain, datarate);
+ if (ret)
+ goto pdown;
+
+ ret = ads1119_cmd(st, ADS1119_CMD_START_SYNC);
+ if (ret)
+ goto pdown;
+
+ ret = ads1119_read_data(st, chan, &sample);
+ if (ret)
+ goto pdown;
+
+ *val = sign_extend32(sample, chan->scan_type.realbits - 1);
+ ret = IIO_VAL_INT;
+pdown:
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
+end:
+ return ret;
+}
+
+static int ads1119_validate_datarate(struct ads1119_state *st, int datarate)
+{
+ switch (datarate) {
+ case 20:
+ case 90:
+ case 330:
+ case 1000:
+ return datarate;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ads1119_validate_gain(struct ads1119_state *st, int scale, int uscale)
+{
+ int gain = 1000000 / ((scale * 1000000) + uscale);
+
+ switch (gain) {
+ case 1:
+ case 4:
+ return gain;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ads1119_read_avail(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ const int **vals, int *type, int *length,
+ long mask)
+{
+ switch (mask) {
+ case IIO_CHAN_INFO_SCALE:
+ *type = IIO_VAL_FRACTIONAL;
+ *vals = ads1119_available_gains;
+ *length = ARRAY_SIZE(ads1119_available_gains);
+ return IIO_AVAIL_LIST;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *type = IIO_VAL_INT;
+ *vals = ads1119_available_datarates;
+ *length = ARRAY_SIZE(ads1119_available_datarates);
+ return IIO_AVAIL_LIST;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ads1119_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int *val,
+ int *val2, long mask)
+{
+ struct ads1119_state *st = iio_priv(indio_dev);
+ unsigned int index = chan->address;
+
+ if (index >= st->num_channels_cfg)
+ return -EINVAL;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ iio_device_claim_direct_scoped(return -EBUSY, indio_dev)
+ return ads1119_single_conversion(st, chan, val, false);
+ unreachable();
+ case IIO_CHAN_INFO_OFFSET:
+ iio_device_claim_direct_scoped(return -EBUSY, indio_dev)
+ return ads1119_single_conversion(st, chan, val, true);
+ unreachable();
+ case IIO_CHAN_INFO_SCALE:
+ *val = st->vref_uV / 1000;
+ *val /= st->channels_cfg[index].gain;
+ *val2 = chan->scan_type.realbits - 1;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *val = st->channels_cfg[index].datarate;
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int ads1119_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int val,
+ int val2, long mask)
+{
+ struct ads1119_state *st = iio_priv(indio_dev);
+ unsigned int index = chan->address;
+ int ret;
+
+ if (index >= st->num_channels_cfg)
+ return -EINVAL;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SCALE:
+ ret = ads1119_validate_gain(st, val, val2);
+ if (ret < 0)
+ return ret;
+
+ st->channels_cfg[index].gain = ret;
+ break;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ ret = ads1119_validate_datarate(st, val);
+ if (ret < 0)
+ return ret;
+
+ st->channels_cfg[index].datarate = ret;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int ads1119_debugfs_reg_access(struct iio_dev *indio_dev, unsigned int reg,
+ unsigned int writeval, unsigned int *readval)
+{
+ struct ads1119_state *st = iio_priv(indio_dev);
+
+ if (reg > ADS1119_REG_STATUS)
+ return -EINVAL;
+
+ if (readval)
+ return ads1119_cmd_rreg(st, reg, readval);
+
+ if (reg > ADS1119_REG_CONFIG)
+ return -EINVAL;
+
+ return ads1119_cmd_wreg(st, writeval);
+}
+
+static const struct iio_info ads1119_info = {
+ .read_avail = ads1119_read_avail,
+ .read_raw = ads1119_read_raw,
+ .write_raw = ads1119_write_raw,
+ .debugfs_reg_access = ads1119_debugfs_reg_access,
+};
+
+static int ads1119_set_trigger_state(struct iio_trigger *trig, bool state)
+{
+ struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+ struct ads1119_state *st = iio_priv(indio_dev);
+ struct device *dev = &st->client->dev;
+ unsigned int index;
+ int ret;
+
+ index = find_first_bit(indio_dev->active_scan_mask,
+ indio_dev->masklength);
+
+ if (index >= st->num_channels_cfg)
+ return -EINVAL;
+
+ st->num_bytes_sample =
+ indio_dev->channels[index].scan_type.storagebits / 8;
+
+ ret = ads1119_set_conv_mode(st, state);
+ if (ret)
+ return ret;
+
+ if (!state) {
+ pm_runtime_mark_last_busy(dev);
+ return pm_runtime_put_autosuspend(dev);
+ }
+
+ ret = ads1119_configure_channel(st,
+ st->channels_cfg[index].mux,
+ st->channels_cfg[index].gain,
+ st->channels_cfg[index].datarate);
+ if (ret)
+ return ret;
+
+ ret = pm_runtime_resume_and_get(dev);
+ if (ret)
+ return ret;
+
+ return ads1119_cmd(st, ADS1119_CMD_START_SYNC);
+}
+
+static const struct iio_trigger_ops ads1119_trigger_ops = {
+ .set_trigger_state = &ads1119_set_trigger_state,
+ .validate_device = &iio_trigger_validate_own_device,
+};
+
+static irqreturn_t ads1119_irq_handler(int irq, void *dev_id)
+{
+ struct iio_dev *indio_dev = dev_id;
+ struct ads1119_state *st = iio_priv(indio_dev);
+
+ if (iio_buffer_enabled(indio_dev))
+ iio_trigger_poll(indio_dev->trig);
+ else
+ complete(&st->completion);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t ads1119_trigger_handler(int irq, void *private)
+{
+ struct iio_poll_func *pf = private;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct ads1119_state *st = iio_priv(indio_dev);
+ unsigned int sample;
+ int ret;
+
+ ret = ads1119_cmd_rdata(st, &sample);
+ if (ret) {
+ dev_err(&st->client->dev,
+ "Failed to read data on trigger (%d)\n", ret);
+ goto done;
+ }
+
+ memcpy(st->scan_buf, &sample, st->num_bytes_sample);
+ iio_push_to_buffers_with_timestamp(indio_dev, st->scan_buf,
+ iio_get_time_ns(indio_dev));
+done:
+ iio_trigger_notify_done(indio_dev->trig);
+ return IRQ_HANDLED;
+}
+
+static int ads1119_init(struct ads1119_state *st, bool vref_external)
+{
+ int ret;
+
+ ret = ads1119_reset(st);
+ if (ret)
+ return ret;
+
+ if (vref_external)
+ return ads1119_update_config_reg(st,
+ ADS1119_CONFIG_VREF_FIELD,
+ FIELD_PREP(ADS1119_CONFIG_VREF_FIELD,
+ ADS1119_VREF_EXTERNAL));
+ return 0;
+}
+
+
+static int ads1119_map_analog_inputs_mux(int ain_pos, int ain_neg, bool differential)
+{
+ if (ain_pos >= ADS1119_MAX_SINGLE_CHANNELS)
+ return -EINVAL;
+
+ if (!differential)
+ return ADS1119_MUX_AIN0 + ain_pos;
+
+ if (ain_pos == 0 && ain_neg == 1)
+ return ADS1119_MUX_AIN0_AIN1;
+ else if (ain_pos == 1 && ain_neg == 2)
+ return ADS1119_MUX_AIN1_AIN2;
+ else if (ain_pos == 2 && ain_neg == 3)
+ return ADS1119_MUX_AIN2_AIN3;
+
+ return -EINVAL;
+}
+
+static int ads1119_alloc_and_config_channels(struct iio_dev *indio_dev)
+{
+ const struct iio_chan_spec ads1119_channel = ADS1119_V_CHAN(0, 0, 0);
+ const struct iio_chan_spec ads1119_timestamp = IIO_CHAN_SOFT_TIMESTAMP(0);
+ struct ads1119_state *st = iio_priv(indio_dev);
+ struct iio_chan_spec *iio_channels, *chan;
+ struct device *dev = &st->client->dev;
+ unsigned int num_channels, i;
+ bool differential;
+ u32 ain[2];
+ int ret;
+
+ st->num_channels_cfg = device_get_child_node_count(dev);
+ if (st->num_channels_cfg > ADS1119_MAX_CHANNELS)
+ return dev_err_probe(dev, -EINVAL,
+ "Too many channels %d, max is %d\n",
+ st->num_channels_cfg, ADS1119_MAX_CHANNELS);
+
+ st->channels_cfg = devm_kcalloc(dev, st->num_channels_cfg,
+ sizeof(*st->channels_cfg), GFP_KERNEL);
+ if (!st->channels_cfg)
+ return -ENOMEM;
+
+ /* Allocate one more iio channel for the timestamp */
+ num_channels = st->num_channels_cfg + 1;
+ iio_channels = devm_kcalloc(dev, num_channels,
+ sizeof(*iio_channels),
+ GFP_KERNEL);
+ if (!iio_channels)
+ return -ENOMEM;
+
+ i = 0;
+
+ device_for_each_child_node_scoped(dev, child) {
+ chan = &iio_channels[i];
+
+ differential = fwnode_property_present(child, "diff-channels");
+ if (differential)
+ ret = fwnode_property_read_u32_array(child, "diff-channels", ain, 2);
+ else
+ ret = fwnode_property_read_u32(child, "single-channel", &ain[0]);
+
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to get channel property\n");
+
+ ret = ads1119_map_analog_inputs_mux(ain[0], ain[1], differential);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "Invalid channel value\n");
+
+ st->channels_cfg[i].mux = ret;
+ st->channels_cfg[i].gain = ADS1119_DEFAULT_GAIN;
+ st->channels_cfg[i].datarate = ADS1119_DEFAULT_DATARATE;
+ st->scan_masks[i] = BIT(i);
+
+ *chan = ads1119_channel;
+ chan->channel = ain[0];
+ chan->address = i;
+ chan->scan_index = i;
+
+ if (differential) {
+ chan->channel2 = ain[1];
+ chan->differential = 1;
+ }
+
+ dev_dbg(dev, "channel: index %d, mux %d\n", i, st->channels_cfg[i].mux);
+
+ i++;
+ }
+
+ iio_channels[i] = ads1119_timestamp;
+ iio_channels[i].address = i;
+ iio_channels[i].scan_index = i;
+
+ indio_dev->channels = iio_channels;
+ indio_dev->num_channels = num_channels;
+ indio_dev->available_scan_masks = st->scan_masks;
+
+ return 0;
+}
+
+static int ads1119_probe(struct i2c_client *client)
+{
+ struct iio_dev *indio_dev;
+ struct ads1119_state *st;
+ struct device *dev = &client->dev;
+ bool vref_external = true;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
+ if (!indio_dev)
+ return dev_err_probe(dev, -ENOMEM,
+ "Failed to allocate IIO device\n");
+
+ st = iio_priv(indio_dev);
+ st->client = client;
+
+ indio_dev->name = "ads1119";
+ indio_dev->info = &ads1119_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ i2c_set_clientdata(client, indio_dev);
+
+ st->vref_uV = devm_regulator_get_enable_read_voltage(dev, "vref");
+ if (st->vref_uV == -ENODEV) {
+ vref_external = false;
+ st->vref_uV = ADS1119_VREF_INTERNAL_VAL;
+ } else if (st->vref_uV < 0) {
+ return dev_err_probe(dev, st->vref_uV, "Failed to get vref\n");
+ }
+
+ st->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
+ if (IS_ERR(st->reset_gpio))
+ return dev_err_probe(dev, PTR_ERR(st->reset_gpio),
+ "Failed to get reset gpio\n");
+
+ ret = ads1119_alloc_and_config_channels(indio_dev);
+ if (ret)
+ return ret;
+
+ init_completion(&st->completion);
+
+ if (client->irq > 0) {
+ ret = devm_request_threaded_irq(dev,
+ client->irq,
+ ads1119_irq_handler,
+ NULL,
+ IRQF_TRIGGER_FALLING,
+ "ads1119",
+ indio_dev);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to allocate irq\n");
+
+ st->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
+ indio_dev->name,
+ iio_device_id(indio_dev));
+ if (!st->trig)
+ return dev_err_probe(dev, -ENOMEM,
+ "Failed to allocate IIO trigger\n");
+
+ st->trig->ops = &ads1119_trigger_ops;
+ iio_trigger_set_drvdata(st->trig, indio_dev);
+
+ ret = devm_iio_trigger_register(dev, st->trig);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to register IIO trigger\n");
+
+ indio_dev->trig = iio_trigger_get(st->trig);
+
+ ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
+ ads1119_trigger_handler,
+ NULL);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to setup IIO buffer\n");
+ }
+
+ ret = ads1119_init(st, vref_external);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to initialize device\n");
+
+ pm_runtime_set_autosuspend_delay(dev, ADS1119_SUSPEND_DELAY);
+ pm_runtime_use_autosuspend(dev);
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_set_active(dev);
+
+ ret = devm_pm_runtime_enable(dev);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to enable pm runtime\n");
+
+ return devm_iio_device_register(dev, indio_dev);
+}
+
+static int ads1119_runtime_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct ads1119_state *st = iio_priv(indio_dev);
+
+ return ads1119_cmd(st, ADS1119_CMD_POWERDOWN);
+}
+
+/*
+ * The ADS1119 does not require a resume function because it automatically powers
+ * on after a reset.
+ * After a power down command, the ADS1119 can still communicate but turns off its
+ * analog parts. To resume from power down, the device will power up again
+ * upon receiving a start/sync command.
+ */
+static DEFINE_RUNTIME_DEV_PM_OPS(ads1119_pm_ops,
+ ads1119_runtime_suspend,
+ NULL,
+ NULL);
+
+
+static const struct of_device_id __maybe_unused ads1119_of_match[] = {
+ { .compatible = "ti,ads1119" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ads1119_of_match);
+
+static const struct i2c_device_id ads1119_id[] = {
+ { "ads1119", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ads1119_id);
+
+static struct i2c_driver ads1119_driver = {
+ .driver = {
+ .name = "ads1119",
+ .of_match_table = ads1119_of_match,
+ .pm = pm_ptr(&ads1119_pm_ops),
+ },
+ .probe = ads1119_probe,
+ .id_table = ads1119_id,
+};
+module_i2c_driver(ads1119_driver);
+
+MODULE_AUTHOR("João Paulo Gonçalves <joao.goncalves@xxxxxxxxxxx>");
+MODULE_DESCRIPTION("Texas Instruments ADS1119 ADC Driver");
+MODULE_LICENSE("GPL");
--
2.39.2