Add driver for ADS7128 and ADS7138 12-bit, 8-channel analog-to-digital
converters. These ADCs have a wide operating range and a wide feature
set. Communication is based on the I2C interface.
Signed-off-by: Tobias Sperling <tobias.sperling@xxxxxxxxxxx>
---
drivers/iio/adc/Kconfig | 10 +
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/ti-ads7138.c | 796 +++++++++++++++++++++++++++++++++++
3 files changed, 807 insertions(+)
create mode 100644 drivers/iio/adc/ti-ads7138.c
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 6c4e74420fd2..fe956b0cbb72 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -1427,6 +1427,16 @@ config TI_ADS1119
This driver can also be built as a module. If so, the module will be
called ti-ads1119.
+config TI_ADS7138
+ tristate "Texas Instruments ADS7128 and ADS7138 ADC driver"
+ depends on I2C
+ help
+ If you say yes here you get support for Texas Instruments ADS7128 and
+ ADS7138 8-channel A/D converters with 12-bit resolution.
+
+ This driver can also be built as a module. If so, the module will be
+ called ti-ads7138.
+
config TI_ADS7924
tristate "Texas Instruments ADS7924 ADC"
depends on I2C
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 7b91cd98c0e0..38aebe49a1a8 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -130,6 +130,7 @@ 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
+obj-$(CONFIG_TI_ADS7138) += ti-ads7138.o
obj-$(CONFIG_TI_ADS7924) += ti-ads7924.o
obj-$(CONFIG_TI_ADS7950) += ti-ads7950.o
obj-$(CONFIG_TI_ADS8344) += ti-ads8344.o
diff --git a/drivers/iio/adc/ti-ads7138.c b/drivers/iio/adc/ti-ads7138.c
new file mode 100644
index 000000000000..3ac76625bc63
--- /dev/null
+++ b/drivers/iio/adc/ti-ads7138.c
@@ -0,0 +1,796 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * ADS7138 - Texas Instruments Analog-to-Digital Converter
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+
+#include <linux/iio/events.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/types.h>
+
+#define MODULE_NAME "ads71x8"
+
+/* AVDD (VREF) operating range in millivolts */
+#define ADS71x8_AVDD_MV_MIN 2350
+#define ADS71x8_AVDD_MV_MAX 5500
+
+/*
+ * Always assume 16 bits resolution as HW registers are aligned like that and
+ * with enabled oversampling/averaging it actually corresponds to 16 bits.
+ */
+#define ADS71x8_RES_BITS 16
+
+/* ADS71x8 operation codes */
+#define ADS71x8_OPCODE_SET_BIT 0x18
+#define ADS71x8_OPCODE_CLEAR_BIT 0x20
+#define ADS71x8_OPCODE_BLOCK_WRITE 0x28
+#define ADS71x8_OPCODE_BLOCK_READ 0x30
+
+/* ADS71x8 registers */
+#define ADS71x8_REG_GENERAL_CFG 0x01
+#define ADS71x8_REG_OSR_CFG 0x03
+#define ADS71x8_REG_OPMODE_CFG 0x04
+#define ADS71x8_REG_SEQUENCE_CFG 0x10
+#define ADS71x8_REG_AUTO_SEQ_CH_SEL 0x12
+#define ADS71x8_REG_ALERT_CH_SEL 0x14
+#define ADS71x8_REG_EVENT_FLAG 0x18
+#define ADS71x8_REG_EVENT_HIGH_FLAG 0x1A
+#define ADS71x8_REG_EVENT_LOW_FLAG 0x1C
+#define ADS71x8_REG_HIGH_TH_HYS_CH(x) ((x) * 4 + 0x20)
+#define ADS71x8_REG_LOW_TH_CNT_CH(x) ((x) * 4 + 0x22)
+#define ADS71x8_REG_MAX_LSB_CH(x) ((x) * 2 + 0x60)
+#define ADS71x8_REG_MIN_LSB_CH(x) ((x) * 2 + 0x80)
+#define ADS71x8_REG_RECENT_LSB_CH(x) ((x) * 2 + 0xA0)
+
+#define ADS71x8_GENERAL_CFG_RST BIT(0)
+#define ADS71x8_GENERAL_CFG_DWC_EN BIT(4)
+#define ADS71x8_GENERAL_CFG_STATS_EN BIT(5)
+#define ADS71x8_OSR_CFG_MASK GENMASK(2, 0)
+#define ADS71x8_OPMODE_CFG_CONV_MODE BIT(5)
+#define ADS71x8_OPMODE_CFG_FREQ_MASK GENMASK(4, 0)
+#define ADS71x8_SEQUENCE_CFG_SEQ_MODE BIT(0)
+#define ADS71x8_SEQUENCE_CFG_SEQ_START BIT(4)
+#define ADS71x8_THRESHOLD_LSB_MASK GENMASK(7, 4)
+
+enum ads71x8_modes {
+ ADS71x8_MODE_MANUAL,
+ ADS71x8_MODE_AUTO,
+};
+
+enum ads71x8_stats {
+ ADS71x8_STATS_MIN,
+ ADS71x8_STATS_MAX,
+};
+
+enum ads71x8_chips { ads7128, ads7138 };
+
+struct ads71x8_data {
+ struct mutex lock;
+ struct i2c_client *client;
+ struct regulator *vref_regu;
+};
+
+struct ads71x8_freq_bits {
+ u32 hz;
+ u8 bits;
+};
+
+static const struct ads71x8_freq_bits ads71x8_samp_freq[] = {
+ {163, 0x1F}, {244, 0x1E}, {326, 0x1D}, {488, 0x1C}, {651, 0x1B},
+ {977, 0x1A}, {1302, 0x19}, {1953, 0x18}, {2604, 0x17}, {3906, 0x16},
+ {5208, 0x15}, {7813, 0x14}, {10417, 0x13}, {15625, 0x12}, {20833, 0x11},
+ {31250, 0x10}, {41667, 0x09}, {62500, 0x08}, {83333, 0x07},
+ {125000, 0x06}, {166667, 0x05}, {250000, 0x04}, {333333, 0x03},
+ {500000, 0x02}, {666667, 0x01}, {1000000, 0x0}
+};
+
+static int ads71x8_i2c_write_block(const struct i2c_client *client, u8 reg,
+ u8 *values, u8 length)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(client);
+ struct ads71x8_data *data = iio_priv(indio_dev);
+ int ret;
+ struct i2c_msg msgs[] = {
+ {
+ .addr = client->addr,
+ .flags = 0,
+ .len = length + 2, /* "+ 2" for OPCODE and reg */
+ },
+ };
+
+ msgs[0].buf = kmalloc(msgs[0].len, GFP_KERNEL);
+ if (!msgs[0].buf)
+ return -ENOMEM;
+
+ msgs[0].buf[0] = ADS71x8_OPCODE_BLOCK_WRITE;
+ msgs[0].buf[1] = reg;
+ memcpy(&msgs[0].buf[2], values, length);
+
+ mutex_lock(&data->lock);
+ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ mutex_unlock(&data->lock);
+ kfree(msgs[0].buf);
+
+ return ret;
+}
+
+static int ads71x8_i2c_write(const struct i2c_client *client, u8 reg, u8 value)
+{
+ return ads71x8_i2c_write_block(client, reg, &value, sizeof(value));
+}
+
+static int ads71x8_i2c_setclear_bit(const struct i2c_client *client, u8 reg,
+ u8 bits, u8 opcode)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(client);
+ struct ads71x8_data *data = iio_priv(indio_dev);
+ int ret;
+ u8 buf[3] = {opcode, reg, bits};
+ struct i2c_msg msgs[] = {
+ {
+ .addr = client->addr,
+ .flags = 0,
+ .len = ARRAY_SIZE(buf),
+ .buf = buf,
+ },
+ };
+
+ mutex_lock(&data->lock);
+ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ mutex_unlock(&data->lock);
+
+ return ret;
+}
+
+static int ads71x8_i2c_set_bit(const struct i2c_client *client, u8 reg, u8 bits)
+{
+ return ads71x8_i2c_setclear_bit(client, reg, bits,
+ ADS71x8_OPCODE_SET_BIT);
+}
+
+static int ads71x8_i2c_clear_bit(const struct i2c_client *client, u8 reg, u8 bits)
+{
+ return ads71x8_i2c_setclear_bit(client, reg, bits,
+ ADS71x8_OPCODE_CLEAR_BIT);
+}
+
+static int ads71x8_i2c_read_block(const struct i2c_client *client, u8 reg,
+ u8 *out_values, u8 length)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(client);
+ struct ads71x8_data *data = iio_priv(indio_dev);
+ int ret;
+ u8 buf[2] = {ADS71x8_OPCODE_BLOCK_READ, reg};
+ struct i2c_msg msgs[] = {
+ {
+ .addr = client->addr,
+ .flags = 0,
+ .len = ARRAY_SIZE(buf),
+ .buf = buf,
+ },
+ {
+ .addr = client->addr,
+ .flags = I2C_M_RD,
+ .len = length,
+ .buf = out_values,
+ },
+ };
+
+ mutex_lock(&data->lock);
+ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ mutex_unlock(&data->lock);
+
+ return ret;
+}
+
+static int ads71x8_i2c_read(const struct i2c_client *client, u8 reg)
+{
+ u8 value;
+ int ret;
+
+ ret = ads71x8_i2c_read_block(client, reg, &value, sizeof(value));
+ if (ret < 0)
+ return ret;
+ return value;
+}
+
+static const struct ads71x8_freq_bits *get_closest_freq(int freq)
+{
+ const int idx_max = ARRAY_SIZE(ads71x8_samp_freq) - 1;
+ u32 cur, best = ads71x8_samp_freq[idx_max].hz;
+ int i;
+
+ freq = clamp_val(freq, ads71x8_samp_freq[0].hz,
+ ads71x8_samp_freq[idx_max].hz);
+
+ for (i = 0; i <= idx_max; i++) {
+ cur = abs(ads71x8_samp_freq[i].hz - freq);
+ if (cur > best)
+ return &ads71x8_samp_freq[i-1];
+ best = cur;
+ }
+ return &ads71x8_samp_freq[idx_max];
+}
+
+static u32 get_closest_log2(u32 val)
+{
+ u32 down = ilog2(val);
+ u32 up = ilog2(roundup_pow_of_two(val));
+
+ return (val - (1 << down) < (1 << up) - val) ? down : up;
+}
+
+static int ads71x8_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int *val, int *val2, long mask)
+{
+ struct ads71x8_data *data = iio_priv(indio_dev);
+ int i, ret, vref;
+ u8 values[2];
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = ads71x8_i2c_read_block(data->client,
+ ADS71x8_REG_RECENT_LSB_CH(chan->channel), values,
+ ARRAY_SIZE(values));
+ if (ret < 0)
+ return ret;
+
+ *val = ((values[1] << 8) | values[0]);
+ ret = IIO_VAL_INT;
+ break;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ ret = ads71x8_i2c_read(data->client, ADS71x8_REG_OPMODE_CFG);
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < ARRAY_SIZE(ads71x8_samp_freq); i++) {
+ if (ads71x8_samp_freq[i].bits ==
+ (ret & ADS71x8_OPMODE_CFG_FREQ_MASK)) {
+ *val = ads71x8_samp_freq[i].hz;
+ return IIO_VAL_INT;
+ }
+ }
+
+ ret = -EINVAL;
+ break;
+ case IIO_CHAN_INFO_SCALE:
+ if (data->vref_regu) {
+ vref = regulator_get_voltage(data->vref_regu);
+ if (vref < 0)
+ return vref;
+ *val = vref / 1000;
+ } else {
+ *val = ADS71x8_AVDD_MV_MIN;
+ }
+ *val2 = ADS71x8_RES_BITS;
+ ret = IIO_VAL_FRACTIONAL_LOG2;
+ break;
+ case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+ ret = ads71x8_i2c_read(data->client, ADS71x8_REG_OSR_CFG);
+ if (ret < 0)
+ return ret;
+ *val = (1 << (ret & ADS71x8_OSR_CFG_MASK));
+ ret = IIO_VAL_INT;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+static int ads71x8_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int val, int val2, long mask)
+{
+ struct ads71x8_data *data = iio_priv(indio_dev);
+ const struct ads71x8_freq_bits *freq = NULL;
+ int ret;
+ u8 osr_val;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ freq = get_closest_freq(val);
+ ret = ads71x8_i2c_read(data->client, ADS71x8_REG_OPMODE_CFG);
+ if (ret < 0)
+ return ret;
+ ret = ads71x8_i2c_write(data->client, ADS71x8_REG_OPMODE_CFG,
+ (ret & ~ADS71x8_OPMODE_CFG_FREQ_MASK) |
+ (freq->bits & ADS71x8_OPMODE_CFG_FREQ_MASK));
+ ret = (ret > 0) ? 0 : ret;
+ break;
+ case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+ /* Number of samples can only be a power of 2 */
+ osr_val = get_closest_log2(clamp_val(val, 1, 128));
+ ret = ads71x8_i2c_write(data->client, ADS71x8_REG_OSR_CFG,
+ osr_val);
+ ret = (ret > 0) ? 0 : ret;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+static ssize_t ads71x8_read_stats(struct iio_dev *indio_dev, uintptr_t priv,
+ const struct iio_chan_spec *chan, char *buf)
+{
+ struct ads71x8_data *data = iio_priv(indio_dev);
+ int ret;
+ u8 values[2];
+
+ switch (priv) {
+ case ADS71x8_STATS_MIN:
+ ret = ads71x8_i2c_read_block(data->client,
+ ADS71x8_REG_MIN_LSB_CH(chan->channel), values,
+ ARRAY_SIZE(values));
+ if (ret < 0)
+ return ret;
+ break;
+ case ADS71x8_STATS_MAX:
+ ret = ads71x8_i2c_read_block(data->client,
+ ADS71x8_REG_MAX_LSB_CH(chan->channel), values,
+ ARRAY_SIZE(values));
+ if (ret < 0)
+ return ret;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return sprintf(buf, "%d\n", ((values[1] << 8) | values[0]));
+}
+
+static int ads71x8_read_event(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan, enum iio_event_type type,
+ enum iio_event_direction dir, enum iio_event_info info, int *val,
+ int *val2)
+{
+ int ret;
+ u8 reg, values[2];
+ struct ads71x8_data *data = iio_priv(indio_dev);
+
+ switch (info) {
+ case IIO_EV_INFO_VALUE:
+ reg = (dir == IIO_EV_DIR_RISING) ?
+ ADS71x8_REG_HIGH_TH_HYS_CH(chan->channel) :
+ ADS71x8_REG_LOW_TH_CNT_CH(chan->channel);
+ ret = ads71x8_i2c_read_block(data->client, reg, values,
+ ARRAY_SIZE(values));
+ if (ret < 0)
+ return ret;
+
+ *val = ((values[1] << 4) | (values[0] >> 4));
+ ret = IIO_VAL_INT;
+ break;
+ case IIO_EV_INFO_HYSTERESIS:
+ ret = ads71x8_i2c_read(data->client,
+ ADS71x8_REG_HIGH_TH_HYS_CH(chan->channel));
+ if (ret < 0)
+ return ret;
+
+ *val = (ret & ~ADS71x8_THRESHOLD_LSB_MASK);
+ ret = IIO_VAL_INT;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+static int ads71x8_write_event(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan, enum iio_event_type type,
+ enum iio_event_direction dir, enum iio_event_info info, int val,
+ int val2)
+{
+ struct ads71x8_data *data = iio_priv(indio_dev);
+ int ret;
+ u8 reg, values[2];
+
+ switch (info) {
+ case IIO_EV_INFO_VALUE:
+ if (val >= BIT(12) || val < 0) {
+ ret = -EINVAL;
+ break;
+ }
+ reg = (dir == IIO_EV_DIR_RISING) ?
+ ADS71x8_REG_HIGH_TH_HYS_CH(chan->channel) :
+ ADS71x8_REG_LOW_TH_CNT_CH(chan->channel);
+
+ ret = ads71x8_i2c_read(data->client, reg);
+ if (ret < 0)
+ return ret;
+
+ values[0] = (((val & 0x0F) << 4) |
+ (ret & ~ADS71x8_THRESHOLD_LSB_MASK));
+ values[1] = (val >> 4);
+ ret = ads71x8_i2c_write_block(data->client, reg, values,
+ ARRAY_SIZE(values));
+ ret = (ret > 0) ? 0 : ret;
+ break;
+ case IIO_EV_INFO_HYSTERESIS:
+ if (val >= BIT(4) || val < 0) {
+ ret = -EINVAL;
+ break;
+ }
+ reg = ADS71x8_REG_HIGH_TH_HYS_CH(chan->channel);
+ ret = ads71x8_i2c_read(data->client, reg);
+ if (ret < 0)
+ return ret;
+
+ ret = ads71x8_i2c_write(data->client, reg,
+ ((ret & ADS71x8_THRESHOLD_LSB_MASK) |
+ (val & ~ADS71x8_THRESHOLD_LSB_MASK)));
+ ret = (ret > 0) ? 0 : ret;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+static int ads71x8_read_event_config(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan, enum iio_event_type type,
+ enum iio_event_direction dir)
+{
+ struct ads71x8_data *data = iio_priv(indio_dev);
+ int ret;
+
+ switch (dir) {
+ case IIO_EV_DIR_EITHER:
+ ret = ads71x8_i2c_read(data->client, ADS71x8_REG_ALERT_CH_SEL);
+ if (ret < 0)
+ return ret;
+
+ ret = (ret & BIT(chan->channel)) ? 1 : 0;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+static int ads71x8_write_event_config(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan, enum iio_event_type type,
+ enum iio_event_direction dir, int state)
+{
+ struct ads71x8_data *data = iio_priv(indio_dev);
+ int ret;
+
+ switch (dir) {
+ case IIO_EV_DIR_EITHER:
+ if (state)
+ ret = ads71x8_i2c_set_bit(data->client,
+ ADS71x8_REG_ALERT_CH_SEL, BIT(chan->channel));
+ else
+ ret = ads71x8_i2c_clear_bit(data->client,
+ ADS71x8_REG_ALERT_CH_SEL, BIT(chan->channel));
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+static ssize_t ads71x8_show_samp_freq_avail(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int i;
+ ssize_t len = 0;
+
+ for (i = 0; i < ARRAY_SIZE(ads71x8_samp_freq); i++)
+ len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
+ ads71x8_samp_freq[i].hz);
+ buf[len - 1] = '\n';
+
+ return len;
+}
+
+static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(ads71x8_show_samp_freq_avail);
+
+static struct attribute *ads71x8_attributes[] = {
+ &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group ads71x8_attribute_group = {
+ .attrs = ads71x8_attributes,
+};
+
+static const struct iio_info ti_ads71x8_info = {
+ .attrs = &ads71x8_attribute_group,
+ .read_raw = &ads71x8_read_raw,
+ .write_raw = &ads71x8_write_raw,
+ .read_event_value = &ads71x8_read_event,
+ .write_event_value = &ads71x8_write_event,
+ .read_event_config = &ads71x8_read_event_config,
+ .write_event_config = &ads71x8_write_event_config,
+};
+
+static const struct iio_event_spec ads71x8_events[] = {
+ {
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_RISING,
+ .mask_separate = BIT(IIO_EV_INFO_VALUE)
+ }, {
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_FALLING,
+ .mask_separate = BIT(IIO_EV_INFO_VALUE),
+ }, {
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_EITHER,
+ .mask_separate = BIT(IIO_EV_INFO_HYSTERESIS) |
+ BIT(IIO_EV_INFO_ENABLE),
+ },
+};
+
+static const struct iio_chan_spec_ext_info ads71x8_ext_info[] = {
+ {"stats_min", IIO_SEPARATE, ads71x8_read_stats, NULL, ADS71x8_STATS_MIN},
+ {"stats_max", IIO_SEPARATE, ads71x8_read_stats, NULL, ADS71x8_STATS_MAX},
+ {},
+};
+
+#define ADS71x8_V_CHAN(_chan) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .channel = _chan, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
+ BIT(IIO_CHAN_INFO_SCALE) | \
+ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
+ .datasheet_name = "AIN"#_chan, \
+ .event_spec = ads71x8_events, \
+ .num_event_specs = ARRAY_SIZE(ads71x8_events), \
+ .ext_info = ads71x8_ext_info, \
+}
+
+static const struct iio_chan_spec ads71x8_channels[] = {
+ ADS71x8_V_CHAN(0),
+ ADS71x8_V_CHAN(1),
+ ADS71x8_V_CHAN(2),
+ ADS71x8_V_CHAN(3),
+ ADS71x8_V_CHAN(4),
+ ADS71x8_V_CHAN(5),
+ ADS71x8_V_CHAN(6),
+ ADS71x8_V_CHAN(7),
+};
+
+static irqreturn_t ads71x8_event_handler(int irq, void *priv)
+{
+ struct iio_dev *indio_dev = priv;
+ struct ads71x8_data *data = iio_priv(indio_dev);
+ int ret;
+ u8 i, events_high, events_low;
+ u64 code;
+
+ /* Check if interrupt was trigger by us */
+ ret = ads71x8_i2c_read(data->client, ADS71x8_REG_EVENT_FLAG);
+ if (ret <= 0)
+ return IRQ_NONE;
+
+ ret = ads71x8_i2c_read(data->client, ADS71x8_REG_EVENT_HIGH_FLAG);
+ events_high = ret;
+ if (ret < 0)
+ goto out;
+
+ ret = ads71x8_i2c_read(data->client, ADS71x8_REG_EVENT_LOW_FLAG);
+ events_low = ret;
+ if (ret < 0)
+ goto out;
+
+ for (i = 0; i < 8; i++) {
+ if (events_high & BIT(i)) {
+ code = IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, i,
+ IIO_EV_TYPE_THRESH, IIO_EV_DIR_RISING);
+ iio_push_event(indio_dev, code,
+ iio_get_time_ns(indio_dev));
+ }
+ if (events_low & BIT(i)) {
+ code = IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, i,
+ IIO_EV_TYPE_THRESH, IIO_EV_DIR_FALLING);
+ iio_push_event(indio_dev, code,
+ iio_get_time_ns(indio_dev));
+ }
+ }
+
+ /* Clear all interrupt flags */
+ ads71x8_i2c_write(data->client, ADS71x8_REG_EVENT_HIGH_FLAG, 0xFF);
+ ads71x8_i2c_write(data->client, ADS71x8_REG_EVENT_LOW_FLAG, 0xFF);
+
+out:
+ if (ret < 0)
+ dev_warn(&data->client->dev,
+ "Couldn't handle interrupt correctly: %d\n", ret);
+ return IRQ_HANDLED;
+}
+
+static int ads71x8_set_conv_mode(struct ads71x8_data *data,
+ enum ads71x8_modes mode)
+{
+ if (mode == ADS71x8_MODE_AUTO)
+ return ads71x8_i2c_set_bit(data->client, ADS71x8_REG_OPMODE_CFG,
+ ADS71x8_OPMODE_CFG_CONV_MODE);
+ return ads71x8_i2c_clear_bit(data->client, ADS71x8_REG_OPMODE_CFG,
+ ADS71x8_OPMODE_CFG_CONV_MODE);
+}
+
+static int ads7138_init_hw(struct ads71x8_data *data)
+{
+ int ret = 0;
+
+ data->vref_regu = devm_regulator_get(&data->client->dev, "avdd");
+ if (IS_ERR(data->vref_regu))
+ data->vref_regu = NULL;
+
+ /* Reset the chip to get a defined starting configuration */
+ ret = ads71x8_i2c_set_bit(data->client, ADS71x8_REG_GENERAL_CFG,
+ ADS71x8_GENERAL_CFG_RST);
+ if (ret < 0)
+ goto cleanup_config;
+
+ ret = ads71x8_set_conv_mode(data, ADS71x8_MODE_AUTO);
+ if (ret < 0)
+ goto cleanup_config;
+
+ /* Enable statistics and digital window comparator */
+ ret = ads71x8_i2c_set_bit(data->client, ADS71x8_REG_GENERAL_CFG,
+ (ADS71x8_GENERAL_CFG_STATS_EN | ADS71x8_GENERAL_CFG_DWC_EN));
+ if (ret < 0)
+ goto cleanup_config;
+
+ /* Enable all channels for auto sequencing */
+ ret = ads71x8_i2c_set_bit(data->client, ADS71x8_REG_AUTO_SEQ_CH_SEL, 0xFF);
+ if (ret < 0)
+ goto cleanup_config;
+
+ /* Set auto sequence mode and start sequencing */
+ ret = ads71x8_i2c_set_bit(data->client, ADS71x8_REG_SEQUENCE_CFG,
+ (ADS71x8_SEQUENCE_CFG_SEQ_START | ADS71x8_SEQUENCE_CFG_SEQ_MODE));
+ if (ret < 0)
+ goto cleanup_config;
+
+ return 0;
+
+cleanup_config:
+ return ret;
+}
+
+static int ads71x8_probe(struct i2c_client *client)
+{
+ const struct i2c_device_id *id = i2c_client_get_device_id(client);
+ struct iio_dev *indio_dev;
+ struct ads71x8_data *data;
+ int ret = 0;
+
+ indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+ if (!indio_dev) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ data = iio_priv(indio_dev);
+ data->client = client;
+ i2c_set_clientdata(client, indio_dev);
+ mutex_init(&data->lock);
+
+ indio_dev->dev.parent = &client->dev;
+ indio_dev->dev.of_node = client->dev.of_node;
+ indio_dev->name = id->name;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = ads71x8_channels;
+ indio_dev->num_channels = ARRAY_SIZE(ads71x8_channels);
+ indio_dev->info = &ti_ads71x8_info;
+
+ ret = devm_request_threaded_irq(&client->dev, client->irq,
+ NULL, ads71x8_event_handler,
+ IRQF_TRIGGER_LOW | IRQF_ONESHOT | IRQF_SHARED,
+ client->name, indio_dev);
+ if (ret)
+ goto cleanup_mutex;
+
+ ret = iio_device_register(indio_dev);
+ if (ret) {
+ dev_err(&client->dev, "Failed to register iio device\n");
+ goto cleanup_mutex;
+ }
+
+ ret = ads7138_init_hw(data);
+ if (ret) {
+ dev_err(&client->dev, "Failed to initialize device\n");
+ goto cleanup_iio;
+ }
+
+ return 0;
+
+cleanup_iio:
+ iio_device_unregister(indio_dev);
+cleanup_mutex:
+ mutex_destroy(&data->lock);
+out:
+ return ret;
+}
+
+static void ads71x8_remove(struct i2c_client *client)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(client);
+ struct ads71x8_data *data = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+ mutex_destroy(&data->lock);
+}
+
+#ifdef CONFIG_PM
+static int ads71x8_runtime_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct ads71x8_data *data = iio_priv(indio_dev);
+
+ return ads71x8_set_conv_mode(data, ADS71x8_MODE_MANUAL);
+}
+
+static int ads71x8_runtime_resume(struct device *dev)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct ads71x8_data *data = iio_priv(indio_dev);
+
+ return ads71x8_set_conv_mode(data, ADS71x8_MODE_AUTO);
+}
+#endif
+
+static const struct dev_pm_ops ads71x8_pm_ops = {
+ SET_RUNTIME_PM_OPS(ads71x8_runtime_suspend, ads71x8_runtime_resume, NULL)
+};
+
+static const struct of_device_id __maybe_unused ads71x8_of_match[] = {
+ {
+ .compatible = "ti,ads7128",
+ .data = (void *)ads7128
+ },
+ {
+ .compatible = "ti,ads7138",
+ .data = (void *)ads7138
+ },
+ { },
+};
+MODULE_DEVICE_TABLE(of, ads71x8_of_match);
+
+static const struct i2c_device_id ads71x8_device_ids[] = {
+ { "ads7128", ads7128 },
+ { "ads7138", ads7138 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ads71x8_device_ids);
+
+static struct i2c_driver ads71x8_driver = {
+ .driver = {
+ .name = MODULE_NAME,
+ .of_match_table = of_match_ptr(ads71x8_of_match),
+ .pm = &ads71x8_pm_ops,
+ },
+ .id_table = ads71x8_device_ids,
+ .probe = ads71x8_probe,
+ .remove = ads71x8_remove,
+};
+module_i2c_driver(ads71x8_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Tobias Sperling <tobias.sperling@xxxxxxxxxxx>");
+MODULE_DESCRIPTION("Driver for TI ADS71x8 ADCs");
--
2.34.1
