Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1156 insertions, 0 deletions

diff --git a/drivers/iio/adc/ti-ads1015.c b/drivers/iio/adc/ti-ads1015.c
new file mode 100644
index 000000000..b1cccc3ee
--- /dev/null
+++ b/drivers/iio/adc/ti-ads1015.c
@@ -0,0 +1,1156 @@
+/*
+ * ADS1015 - Texas Instruments Analog-to-Digital Converter
+ *
+ * Copyright (c) 2016, Intel Corporation.
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License.  See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * IIO driver for ADS1015 ADC 7-bit I2C slave address:
+ *	* 0x48 - ADDR connected to Ground
+ *	* 0x49 - ADDR connected to Vdd
+ *	* 0x4A - ADDR connected to SDA
+ *	* 0x4B - ADDR connected to SCL
+ */
+
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include <linux/pm_runtime.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+
+#include <linux/platform_data/ads1015.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/types.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/events.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+
+#define ADS1015_DRV_NAME "ads1015"
+
+#define ADS1015_CONV_REG	0x00
+#define ADS1015_CFG_REG		0x01
+#define ADS1015_LO_THRESH_REG	0x02
+#define ADS1015_HI_THRESH_REG	0x03
+
+#define ADS1015_CFG_COMP_QUE_SHIFT	0
+#define ADS1015_CFG_COMP_LAT_SHIFT	2
+#define ADS1015_CFG_COMP_POL_SHIFT	3
+#define ADS1015_CFG_COMP_MODE_SHIFT	4
+#define ADS1015_CFG_DR_SHIFT	5
+#define ADS1015_CFG_MOD_SHIFT	8
+#define ADS1015_CFG_PGA_SHIFT	9
+#define ADS1015_CFG_MUX_SHIFT	12
+
+#define ADS1015_CFG_COMP_QUE_MASK	GENMASK(1, 0)
+#define ADS1015_CFG_COMP_LAT_MASK	BIT(2)
+#define ADS1015_CFG_COMP_POL_MASK	BIT(3)
+#define ADS1015_CFG_COMP_MODE_MASK	BIT(4)
+#define ADS1015_CFG_DR_MASK	GENMASK(7, 5)
+#define ADS1015_CFG_MOD_MASK	BIT(8)
+#define ADS1015_CFG_PGA_MASK	GENMASK(11, 9)
+#define ADS1015_CFG_MUX_MASK	GENMASK(14, 12)
+
+/* Comparator queue and disable field */
+#define ADS1015_CFG_COMP_DISABLE	3
+
+/* Comparator polarity field */
+#define ADS1015_CFG_COMP_POL_LOW	0
+#define ADS1015_CFG_COMP_POL_HIGH	1
+
+/* Comparator mode field */
+#define ADS1015_CFG_COMP_MODE_TRAD	0
+#define ADS1015_CFG_COMP_MODE_WINDOW	1
+
+/* device operating modes */
+#define ADS1015_CONTINUOUS	0
+#define ADS1015_SINGLESHOT	1
+
+#define ADS1015_SLEEP_DELAY_MS		2000
+#define ADS1015_DEFAULT_PGA		2
+#define ADS1015_DEFAULT_DATA_RATE	4
+#define ADS1015_DEFAULT_CHAN		0
+
+enum chip_ids {
+	ADS1015,
+	ADS1115,
+};
+
+enum ads1015_channels {
+	ADS1015_AIN0_AIN1 = 0,
+	ADS1015_AIN0_AIN3,
+	ADS1015_AIN1_AIN3,
+	ADS1015_AIN2_AIN3,
+	ADS1015_AIN0,
+	ADS1015_AIN1,
+	ADS1015_AIN2,
+	ADS1015_AIN3,
+	ADS1015_TIMESTAMP,
+};
+
+static const unsigned int ads1015_data_rate[] = {
+	128, 250, 490, 920, 1600, 2400, 3300, 3300
+};
+
+static const unsigned int ads1115_data_rate[] = {
+	8, 16, 32, 64, 128, 250, 475, 860
+};
+
+/*
+ * Translation from PGA bits to full-scale positive and negative input voltage
+ * range in mV
+ */
+static int ads1015_fullscale_range[] = {
+	6144, 4096, 2048, 1024, 512, 256, 256, 256
+};
+
+/*
+ * Translation from COMP_QUE field value to the number of successive readings
+ * exceed the threshold values before an interrupt is generated
+ */
+static const int ads1015_comp_queue[] = { 1, 2, 4 };
+
+static const struct iio_event_spec ads1015_events[] = {
+	{
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_RISING,
+		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
+				BIT(IIO_EV_INFO_ENABLE),
+	}, {
+		.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_ENABLE) |
+				BIT(IIO_EV_INFO_PERIOD),
+	},
+};
+
+#define ADS1015_V_CHAN(_chan, _addr) {				\
+	.type = IIO_VOLTAGE,					\
+	.indexed = 1,						\
+	.address = _addr,					\
+	.channel = _chan,					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
+				BIT(IIO_CHAN_INFO_SCALE) |	\
+				BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
+	.scan_index = _addr,					\
+	.scan_type = {						\
+		.sign = 's',					\
+		.realbits = 12,					\
+		.storagebits = 16,				\
+		.shift = 4,					\
+		.endianness = IIO_CPU,				\
+	},							\
+	.event_spec = ads1015_events,				\
+	.num_event_specs = ARRAY_SIZE(ads1015_events),		\
+	.datasheet_name = "AIN"#_chan,				\
+}
+
+#define ADS1015_V_DIFF_CHAN(_chan, _chan2, _addr) {		\
+	.type = IIO_VOLTAGE,					\
+	.differential = 1,					\
+	.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_SAMP_FREQ),	\
+	.scan_index = _addr,					\
+	.scan_type = {						\
+		.sign = 's',					\
+		.realbits = 12,					\
+		.storagebits = 16,				\
+		.shift = 4,					\
+		.endianness = IIO_CPU,				\
+	},							\
+	.event_spec = ads1015_events,				\
+	.num_event_specs = ARRAY_SIZE(ads1015_events),		\
+	.datasheet_name = "AIN"#_chan"-AIN"#_chan2,		\
+}
+
+#define ADS1115_V_CHAN(_chan, _addr) {				\
+	.type = IIO_VOLTAGE,					\
+	.indexed = 1,						\
+	.address = _addr,					\
+	.channel = _chan,					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
+				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,				\
+	},							\
+	.event_spec = ads1015_events,				\
+	.num_event_specs = ARRAY_SIZE(ads1015_events),		\
+	.datasheet_name = "AIN"#_chan,				\
+}
+
+#define ADS1115_V_DIFF_CHAN(_chan, _chan2, _addr) {		\
+	.type = IIO_VOLTAGE,					\
+	.differential = 1,					\
+	.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_SAMP_FREQ),	\
+	.scan_index = _addr,					\
+	.scan_type = {						\
+		.sign = 's',					\
+		.realbits = 16,					\
+		.storagebits = 16,				\
+		.endianness = IIO_CPU,				\
+	},							\
+	.event_spec = ads1015_events,				\
+	.num_event_specs = ARRAY_SIZE(ads1015_events),		\
+	.datasheet_name = "AIN"#_chan"-AIN"#_chan2,		\
+}
+
+struct ads1015_thresh_data {
+	unsigned int comp_queue;
+	int high_thresh;
+	int low_thresh;
+};
+
+struct ads1015_data {
+	struct regmap *regmap;
+	/*
+	 * Protects ADC ops, e.g: concurrent sysfs/buffered
+	 * data reads, configuration updates
+	 */
+	struct mutex lock;
+	struct ads1015_channel_data channel_data[ADS1015_CHANNELS];
+
+	unsigned int event_channel;
+	unsigned int comp_mode;
+	struct ads1015_thresh_data thresh_data[ADS1015_CHANNELS];
+
+	unsigned int *data_rate;
+	/*
+	 * Set to true when the ADC is switched to the continuous-conversion
+	 * mode and exits from a power-down state.  This flag is used to avoid
+	 * getting the stale result from the conversion register.
+	 */
+	bool conv_invalid;
+};
+
+static bool ads1015_event_channel_enabled(struct ads1015_data *data)
+{
+	return (data->event_channel != ADS1015_CHANNELS);
+}
+
+static void ads1015_event_channel_enable(struct ads1015_data *data, int chan,
+					 int comp_mode)
+{
+	WARN_ON(ads1015_event_channel_enabled(data));
+
+	data->event_channel = chan;
+	data->comp_mode = comp_mode;
+}
+
+static void ads1015_event_channel_disable(struct ads1015_data *data, int chan)
+{
+	data->event_channel = ADS1015_CHANNELS;
+}
+
+static bool ads1015_is_writeable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case ADS1015_CFG_REG:
+	case ADS1015_LO_THRESH_REG:
+	case ADS1015_HI_THRESH_REG:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static const struct regmap_config ads1015_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 16,
+	.max_register = ADS1015_HI_THRESH_REG,
+	.writeable_reg = ads1015_is_writeable_reg,
+};
+
+static const struct iio_chan_spec ads1015_channels[] = {
+	ADS1015_V_DIFF_CHAN(0, 1, ADS1015_AIN0_AIN1),
+	ADS1015_V_DIFF_CHAN(0, 3, ADS1015_AIN0_AIN3),
+	ADS1015_V_DIFF_CHAN(1, 3, ADS1015_AIN1_AIN3),
+	ADS1015_V_DIFF_CHAN(2, 3, ADS1015_AIN2_AIN3),
+	ADS1015_V_CHAN(0, ADS1015_AIN0),
+	ADS1015_V_CHAN(1, ADS1015_AIN1),
+	ADS1015_V_CHAN(2, ADS1015_AIN2),
+	ADS1015_V_CHAN(3, ADS1015_AIN3),
+	IIO_CHAN_SOFT_TIMESTAMP(ADS1015_TIMESTAMP),
+};
+
+static const struct iio_chan_spec ads1115_channels[] = {
+	ADS1115_V_DIFF_CHAN(0, 1, ADS1015_AIN0_AIN1),
+	ADS1115_V_DIFF_CHAN(0, 3, ADS1015_AIN0_AIN3),
+	ADS1115_V_DIFF_CHAN(1, 3, ADS1015_AIN1_AIN3),
+	ADS1115_V_DIFF_CHAN(2, 3, ADS1015_AIN2_AIN3),
+	ADS1115_V_CHAN(0, ADS1015_AIN0),
+	ADS1115_V_CHAN(1, ADS1015_AIN1),
+	ADS1115_V_CHAN(2, ADS1015_AIN2),
+	ADS1115_V_CHAN(3, ADS1015_AIN3),
+	IIO_CHAN_SOFT_TIMESTAMP(ADS1015_TIMESTAMP),
+};
+
+#ifdef CONFIG_PM
+static int ads1015_set_power_state(struct ads1015_data *data, bool on)
+{
+	int ret;
+	struct device *dev = regmap_get_device(data->regmap);
+
+	if (on) {
+		ret = pm_runtime_get_sync(dev);
+		if (ret < 0)
+			pm_runtime_put_noidle(dev);
+	} else {
+		pm_runtime_mark_last_busy(dev);
+		ret = pm_runtime_put_autosuspend(dev);
+	}
+
+	return ret < 0 ? ret : 0;
+}
+
+#else /* !CONFIG_PM */
+
+static int ads1015_set_power_state(struct ads1015_data *data, bool on)
+{
+	return 0;
+}
+
+#endif /* !CONFIG_PM */
+
+static
+int ads1015_get_adc_result(struct ads1015_data *data, int chan, int *val)
+{
+	int ret, pga, dr, dr_old, conv_time;
+	unsigned int old, mask, cfg;
+
+	if (chan < 0 || chan >= ADS1015_CHANNELS)
+		return -EINVAL;
+
+	ret = regmap_read(data->regmap, ADS1015_CFG_REG, &old);
+	if (ret)
+		return ret;
+
+	pga = data->channel_data[chan].pga;
+	dr = data->channel_data[chan].data_rate;
+	mask = ADS1015_CFG_MUX_MASK | ADS1015_CFG_PGA_MASK |
+		ADS1015_CFG_DR_MASK;
+	cfg = chan << ADS1015_CFG_MUX_SHIFT | pga << ADS1015_CFG_PGA_SHIFT |
+		dr << ADS1015_CFG_DR_SHIFT;
+
+	if (ads1015_event_channel_enabled(data)) {
+		mask |= ADS1015_CFG_COMP_QUE_MASK | ADS1015_CFG_COMP_MODE_MASK;
+		cfg |= data->thresh_data[chan].comp_queue <<
+				ADS1015_CFG_COMP_QUE_SHIFT |
+			data->comp_mode <<
+				ADS1015_CFG_COMP_MODE_SHIFT;
+	}
+
+	cfg = (old & ~mask) | (cfg & mask);
+	if (old != cfg) {
+		ret = regmap_write(data->regmap, ADS1015_CFG_REG, cfg);
+		if (ret)
+			return ret;
+		data->conv_invalid = true;
+	}
+	if (data->conv_invalid) {
+		dr_old = (old & ADS1015_CFG_DR_MASK) >> ADS1015_CFG_DR_SHIFT;
+		conv_time = DIV_ROUND_UP(USEC_PER_SEC, data->data_rate[dr_old]);
+		conv_time += DIV_ROUND_UP(USEC_PER_SEC, data->data_rate[dr]);
+		conv_time += conv_time / 10; /* 10% internal clock inaccuracy */
+		usleep_range(conv_time, conv_time + 1);
+		data->conv_invalid = false;
+	}
+
+	return regmap_read(data->regmap, ADS1015_CONV_REG, val);
+}
+
+static irqreturn_t ads1015_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct ads1015_data *data = iio_priv(indio_dev);
+	/* Ensure natural alignment of timestamp */
+	struct {
+		s16 chan;
+		s64 timestamp __aligned(8);
+	} scan;
+	int chan, ret, res;
+
+	memset(&scan, 0, sizeof(scan));
+
+	mutex_lock(&data->lock);
+	chan = find_first_bit(indio_dev->active_scan_mask,
+			      indio_dev->masklength);
+	ret = ads1015_get_adc_result(data, chan, &res);
+	if (ret < 0) {
+		mutex_unlock(&data->lock);
+		goto err;
+	}
+
+	scan.chan = res;
+	mutex_unlock(&data->lock);
+
+	iio_push_to_buffers_with_timestamp(indio_dev, &scan,
+					   iio_get_time_ns(indio_dev));
+
+err:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static int ads1015_set_scale(struct ads1015_data *data,
+			     struct iio_chan_spec const *chan,
+			     int scale, int uscale)
+{
+	int i;
+	int fullscale = div_s64((scale * 1000000LL + uscale) <<
+				(chan->scan_type.realbits - 1), 1000000);
+
+	for (i = 0; i < ARRAY_SIZE(ads1015_fullscale_range); i++) {
+		if (ads1015_fullscale_range[i] == fullscale) {
+			data->channel_data[chan->address].pga = i;
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int ads1015_set_data_rate(struct ads1015_data *data, int chan, int rate)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(ads1015_data_rate); i++) {
+		if (data->data_rate[i] == rate) {
+			data->channel_data[chan].data_rate = i;
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int ads1015_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan, int *val,
+			    int *val2, long mask)
+{
+	int ret, idx;
+	struct ads1015_data *data = iio_priv(indio_dev);
+
+	mutex_lock(&data->lock);
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW: {
+		int shift = chan->scan_type.shift;
+
+		ret = iio_device_claim_direct_mode(indio_dev);
+		if (ret)
+			break;
+
+		if (ads1015_event_channel_enabled(data) &&
+				data->event_channel != chan->address) {
+			ret = -EBUSY;
+			goto release_direct;
+		}
+
+		ret = ads1015_set_power_state(data, true);
+		if (ret < 0)
+			goto release_direct;
+
+		ret = ads1015_get_adc_result(data, chan->address, val);
+		if (ret < 0) {
+			ads1015_set_power_state(data, false);
+			goto release_direct;
+		}
+
+		*val = sign_extend32(*val >> shift, 15 - shift);
+
+		ret = ads1015_set_power_state(data, false);
+		if (ret < 0)
+			goto release_direct;
+
+		ret = IIO_VAL_INT;
+release_direct:
+		iio_device_release_direct_mode(indio_dev);
+		break;
+	}
+	case IIO_CHAN_INFO_SCALE:
+		idx = data->channel_data[chan->address].pga;
+		*val = ads1015_fullscale_range[idx];
+		*val2 = chan->scan_type.realbits - 1;
+		ret = IIO_VAL_FRACTIONAL_LOG2;
+		break;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		idx = data->channel_data[chan->address].data_rate;
+		*val = data->data_rate[idx];
+		ret = IIO_VAL_INT;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int ads1015_write_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan, int val,
+			     int val2, long mask)
+{
+	struct ads1015_data *data = iio_priv(indio_dev);
+	int ret;
+
+	mutex_lock(&data->lock);
+	switch (mask) {
+	case IIO_CHAN_INFO_SCALE:
+		ret = ads1015_set_scale(data, chan, val, val2);
+		break;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		ret = ads1015_set_data_rate(data, chan->address, val);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int ads1015_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)
+{
+	struct ads1015_data *data = iio_priv(indio_dev);
+	int ret;
+	unsigned int comp_queue;
+	int period;
+	int dr;
+
+	mutex_lock(&data->lock);
+
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		*val = (dir == IIO_EV_DIR_RISING) ?
+			data->thresh_data[chan->address].high_thresh :
+			data->thresh_data[chan->address].low_thresh;
+		ret = IIO_VAL_INT;
+		break;
+	case IIO_EV_INFO_PERIOD:
+		dr = data->channel_data[chan->address].data_rate;
+		comp_queue = data->thresh_data[chan->address].comp_queue;
+		period = ads1015_comp_queue[comp_queue] *
+			USEC_PER_SEC / data->data_rate[dr];
+
+		*val = period / USEC_PER_SEC;
+		*val2 = period % USEC_PER_SEC;
+		ret = IIO_VAL_INT_PLUS_MICRO;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int ads1015_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 ads1015_data *data = iio_priv(indio_dev);
+	int realbits = chan->scan_type.realbits;
+	int ret = 0;
+	long long period;
+	int i;
+	int dr;
+
+	mutex_lock(&data->lock);
+
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		if (val >= 1 << (realbits - 1) || val < -1 << (realbits - 1)) {
+			ret = -EINVAL;
+			break;
+		}
+		if (dir == IIO_EV_DIR_RISING)
+			data->thresh_data[chan->address].high_thresh = val;
+		else
+			data->thresh_data[chan->address].low_thresh = val;
+		break;
+	case IIO_EV_INFO_PERIOD:
+		dr = data->channel_data[chan->address].data_rate;
+		period = val * USEC_PER_SEC + val2;
+
+		for (i = 0; i < ARRAY_SIZE(ads1015_comp_queue) - 1; i++) {
+			if (period <= ads1015_comp_queue[i] *
+					USEC_PER_SEC / data->data_rate[dr])
+				break;
+		}
+		data->thresh_data[chan->address].comp_queue = i;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int ads1015_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 ads1015_data *data = iio_priv(indio_dev);
+	int ret = 0;
+
+	mutex_lock(&data->lock);
+	if (data->event_channel == chan->address) {
+		switch (dir) {
+		case IIO_EV_DIR_RISING:
+			ret = 1;
+			break;
+		case IIO_EV_DIR_EITHER:
+			ret = (data->comp_mode == ADS1015_CFG_COMP_MODE_WINDOW);
+			break;
+		default:
+			ret = -EINVAL;
+			break;
+		}
+	}
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int ads1015_enable_event_config(struct ads1015_data *data,
+	const struct iio_chan_spec *chan, int comp_mode)
+{
+	int low_thresh = data->thresh_data[chan->address].low_thresh;
+	int high_thresh = data->thresh_data[chan->address].high_thresh;
+	int ret;
+	unsigned int val;
+
+	if (ads1015_event_channel_enabled(data)) {
+		if (data->event_channel != chan->address ||
+			(data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD &&
+				comp_mode == ADS1015_CFG_COMP_MODE_WINDOW))
+			return -EBUSY;
+
+		return 0;
+	}
+
+	if (comp_mode == ADS1015_CFG_COMP_MODE_TRAD) {
+		low_thresh = max(-1 << (chan->scan_type.realbits - 1),
+				high_thresh - 1);
+	}
+	ret = regmap_write(data->regmap, ADS1015_LO_THRESH_REG,
+			low_thresh << chan->scan_type.shift);
+	if (ret)
+		return ret;
+
+	ret = regmap_write(data->regmap, ADS1015_HI_THRESH_REG,
+			high_thresh << chan->scan_type.shift);
+	if (ret)
+		return ret;
+
+	ret = ads1015_set_power_state(data, true);
+	if (ret < 0)
+		return ret;
+
+	ads1015_event_channel_enable(data, chan->address, comp_mode);
+
+	ret = ads1015_get_adc_result(data, chan->address, &val);
+	if (ret) {
+		ads1015_event_channel_disable(data, chan->address);
+		ads1015_set_power_state(data, false);
+	}
+
+	return ret;
+}
+
+static int ads1015_disable_event_config(struct ads1015_data *data,
+	const struct iio_chan_spec *chan, int comp_mode)
+{
+	int ret;
+
+	if (!ads1015_event_channel_enabled(data))
+		return 0;
+
+	if (data->event_channel != chan->address)
+		return 0;
+
+	if (data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD &&
+			comp_mode == ADS1015_CFG_COMP_MODE_WINDOW)
+		return 0;
+
+	ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG,
+				ADS1015_CFG_COMP_QUE_MASK,
+				ADS1015_CFG_COMP_DISABLE <<
+					ADS1015_CFG_COMP_QUE_SHIFT);
+	if (ret)
+		return ret;
+
+	ads1015_event_channel_disable(data, chan->address);
+
+	return ads1015_set_power_state(data, false);
+}
+
+static int ads1015_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 ads1015_data *data = iio_priv(indio_dev);
+	int ret;
+	int comp_mode = (dir == IIO_EV_DIR_EITHER) ?
+		ADS1015_CFG_COMP_MODE_WINDOW : ADS1015_CFG_COMP_MODE_TRAD;
+
+	mutex_lock(&data->lock);
+
+	/* Prevent from enabling both buffer and event at a time */
+	ret = iio_device_claim_direct_mode(indio_dev);
+	if (ret) {
+		mutex_unlock(&data->lock);
+		return ret;
+	}
+
+	if (state)
+		ret = ads1015_enable_event_config(data, chan, comp_mode);
+	else
+		ret = ads1015_disable_event_config(data, chan, comp_mode);
+
+	iio_device_release_direct_mode(indio_dev);
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static irqreturn_t ads1015_event_handler(int irq, void *priv)
+{
+	struct iio_dev *indio_dev = priv;
+	struct ads1015_data *data = iio_priv(indio_dev);
+	int val;
+	int ret;
+
+	/* Clear the latched ALERT/RDY pin */
+	ret = regmap_read(data->regmap, ADS1015_CONV_REG, &val);
+	if (ret)
+		return IRQ_HANDLED;
+
+	if (ads1015_event_channel_enabled(data)) {
+		enum iio_event_direction dir;
+		u64 code;
+
+		dir = data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD ?
+					IIO_EV_DIR_RISING : IIO_EV_DIR_EITHER;
+		code = IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, data->event_channel,
+					IIO_EV_TYPE_THRESH, dir);
+		iio_push_event(indio_dev, code, iio_get_time_ns(indio_dev));
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int ads1015_buffer_preenable(struct iio_dev *indio_dev)
+{
+	struct ads1015_data *data = iio_priv(indio_dev);
+
+	/* Prevent from enabling both buffer and event at a time */
+	if (ads1015_event_channel_enabled(data))
+		return -EBUSY;
+
+	return ads1015_set_power_state(iio_priv(indio_dev), true);
+}
+
+static int ads1015_buffer_postdisable(struct iio_dev *indio_dev)
+{
+	return ads1015_set_power_state(iio_priv(indio_dev), false);
+}
+
+static const struct iio_buffer_setup_ops ads1015_buffer_setup_ops = {
+	.preenable	= ads1015_buffer_preenable,
+	.postenable	= iio_triggered_buffer_postenable,
+	.predisable	= iio_triggered_buffer_predisable,
+	.postdisable	= ads1015_buffer_postdisable,
+	.validate_scan_mask = &iio_validate_scan_mask_onehot,
+};
+
+static IIO_CONST_ATTR_NAMED(ads1015_scale_available, scale_available,
+	"3 2 1 0.5 0.25 0.125");
+static IIO_CONST_ATTR_NAMED(ads1115_scale_available, scale_available,
+	"0.1875 0.125 0.0625 0.03125 0.015625 0.007813");
+
+static IIO_CONST_ATTR_NAMED(ads1015_sampling_frequency_available,
+	sampling_frequency_available, "128 250 490 920 1600 2400 3300");
+static IIO_CONST_ATTR_NAMED(ads1115_sampling_frequency_available,
+	sampling_frequency_available, "8 16 32 64 128 250 475 860");
+
+static struct attribute *ads1015_attributes[] = {
+	&iio_const_attr_ads1015_scale_available.dev_attr.attr,
+	&iio_const_attr_ads1015_sampling_frequency_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ads1015_attribute_group = {
+	.attrs = ads1015_attributes,
+};
+
+static struct attribute *ads1115_attributes[] = {
+	&iio_const_attr_ads1115_scale_available.dev_attr.attr,
+	&iio_const_attr_ads1115_sampling_frequency_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ads1115_attribute_group = {
+	.attrs = ads1115_attributes,
+};
+
+static const struct iio_info ads1015_info = {
+	.read_raw	= ads1015_read_raw,
+	.write_raw	= ads1015_write_raw,
+	.read_event_value = ads1015_read_event,
+	.write_event_value = ads1015_write_event,
+	.read_event_config = ads1015_read_event_config,
+	.write_event_config = ads1015_write_event_config,
+	.attrs          = &ads1015_attribute_group,
+};
+
+static const struct iio_info ads1115_info = {
+	.read_raw	= ads1015_read_raw,
+	.write_raw	= ads1015_write_raw,
+	.read_event_value = ads1015_read_event,
+	.write_event_value = ads1015_write_event,
+	.read_event_config = ads1015_read_event_config,
+	.write_event_config = ads1015_write_event_config,
+	.attrs          = &ads1115_attribute_group,
+};
+
+#ifdef CONFIG_OF
+static int ads1015_get_channels_config_of(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct ads1015_data *data = iio_priv(indio_dev);
+	struct device_node *node;
+
+	if (!client->dev.of_node ||
+	    !of_get_next_child(client->dev.of_node, NULL))
+		return -EINVAL;
+
+	for_each_child_of_node(client->dev.of_node, node) {
+		u32 pval;
+		unsigned int channel;
+		unsigned int pga = ADS1015_DEFAULT_PGA;
+		unsigned int data_rate = ADS1015_DEFAULT_DATA_RATE;
+
+		if (of_property_read_u32(node, "reg", &pval)) {
+			dev_err(&client->dev, "invalid reg on %pOF\n",
+				node);
+			continue;
+		}
+
+		channel = pval;
+		if (channel >= ADS1015_CHANNELS) {
+			dev_err(&client->dev,
+				"invalid channel index %d on %pOF\n",
+				channel, node);
+			continue;
+		}
+
+		if (!of_property_read_u32(node, "ti,gain", &pval)) {
+			pga = pval;
+			if (pga > 6) {
+				dev_err(&client->dev, "invalid gain on %pOF\n",
+					node);
+				of_node_put(node);
+				return -EINVAL;
+			}
+		}
+
+		if (!of_property_read_u32(node, "ti,datarate", &pval)) {
+			data_rate = pval;
+			if (data_rate > 7) {
+				dev_err(&client->dev,
+					"invalid data_rate on %pOF\n",
+					node);
+				of_node_put(node);
+				return -EINVAL;
+			}
+		}
+
+		data->channel_data[channel].pga = pga;
+		data->channel_data[channel].data_rate = data_rate;
+	}
+
+	return 0;
+}
+#endif
+
+static void ads1015_get_channels_config(struct i2c_client *client)
+{
+	unsigned int k;
+
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct ads1015_data *data = iio_priv(indio_dev);
+	struct ads1015_platform_data *pdata = dev_get_platdata(&client->dev);
+
+	/* prefer platform data */
+	if (pdata) {
+		memcpy(data->channel_data, pdata->channel_data,
+		       sizeof(data->channel_data));
+		return;
+	}
+
+#ifdef CONFIG_OF
+	if (!ads1015_get_channels_config_of(client))
+		return;
+#endif
+	/* fallback on default configuration */
+	for (k = 0; k < ADS1015_CHANNELS; ++k) {
+		data->channel_data[k].pga = ADS1015_DEFAULT_PGA;
+		data->channel_data[k].data_rate = ADS1015_DEFAULT_DATA_RATE;
+	}
+}
+
+static int ads1015_set_conv_mode(struct ads1015_data *data, int mode)
+{
+	return regmap_update_bits(data->regmap, ADS1015_CFG_REG,
+				  ADS1015_CFG_MOD_MASK,
+				  mode << ADS1015_CFG_MOD_SHIFT);
+}
+
+static int ads1015_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct iio_dev *indio_dev;
+	struct ads1015_data *data;
+	int ret;
+	enum chip_ids chip;
+	int i;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	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 = ADS1015_DRV_NAME;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	if (client->dev.of_node)
+		chip = (enum chip_ids)of_device_get_match_data(&client->dev);
+	else
+		chip = id->driver_data;
+	switch (chip) {
+	case ADS1015:
+		indio_dev->channels = ads1015_channels;
+		indio_dev->num_channels = ARRAY_SIZE(ads1015_channels);
+		indio_dev->info = &ads1015_info;
+		data->data_rate = (unsigned int *) &ads1015_data_rate;
+		break;
+	case ADS1115:
+		indio_dev->channels = ads1115_channels;
+		indio_dev->num_channels = ARRAY_SIZE(ads1115_channels);
+		indio_dev->info = &ads1115_info;
+		data->data_rate = (unsigned int *) &ads1115_data_rate;
+		break;
+	}
+
+	data->event_channel = ADS1015_CHANNELS;
+	/*
+	 * Set default lower and upper threshold to min and max value
+	 * respectively.
+	 */
+	for (i = 0; i < ADS1015_CHANNELS; i++) {
+		int realbits = indio_dev->channels[i].scan_type.realbits;
+
+		data->thresh_data[i].low_thresh = -1 << (realbits - 1);
+		data->thresh_data[i].high_thresh = (1 << (realbits - 1)) - 1;
+	}
+
+	/* we need to keep this ABI the same as used by hwmon ADS1015 driver */
+	ads1015_get_channels_config(client);
+
+	data->regmap = devm_regmap_init_i2c(client, &ads1015_regmap_config);
+	if (IS_ERR(data->regmap)) {
+		dev_err(&client->dev, "Failed to allocate register map\n");
+		return PTR_ERR(data->regmap);
+	}
+
+	ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
+					      ads1015_trigger_handler,
+					      &ads1015_buffer_setup_ops);
+	if (ret < 0) {
+		dev_err(&client->dev, "iio triggered buffer setup failed\n");
+		return ret;
+	}
+
+	if (client->irq) {
+		unsigned long irq_trig =
+			irqd_get_trigger_type(irq_get_irq_data(client->irq));
+		unsigned int cfg_comp_mask = ADS1015_CFG_COMP_QUE_MASK |
+			ADS1015_CFG_COMP_LAT_MASK | ADS1015_CFG_COMP_POL_MASK;
+		unsigned int cfg_comp =
+			ADS1015_CFG_COMP_DISABLE << ADS1015_CFG_COMP_QUE_SHIFT |
+			1 << ADS1015_CFG_COMP_LAT_SHIFT;
+
+		switch (irq_trig) {
+		case IRQF_TRIGGER_LOW:
+			cfg_comp |= ADS1015_CFG_COMP_POL_LOW <<
+					ADS1015_CFG_COMP_POL_SHIFT;
+			break;
+		case IRQF_TRIGGER_HIGH:
+			cfg_comp |= ADS1015_CFG_COMP_POL_HIGH <<
+					ADS1015_CFG_COMP_POL_SHIFT;
+			break;
+		default:
+			return -EINVAL;
+		}
+
+		ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG,
+					cfg_comp_mask, cfg_comp);
+		if (ret)
+			return ret;
+
+		ret = devm_request_threaded_irq(&client->dev, client->irq,
+						NULL, ads1015_event_handler,
+						irq_trig | IRQF_ONESHOT,
+						client->name, indio_dev);
+		if (ret)
+			return ret;
+	}
+
+	ret = ads1015_set_conv_mode(data, ADS1015_CONTINUOUS);
+	if (ret)
+		return ret;
+
+	data->conv_invalid = true;
+
+	ret = pm_runtime_set_active(&client->dev);
+	if (ret)
+		return ret;
+	pm_runtime_set_autosuspend_delay(&client->dev, ADS1015_SLEEP_DELAY_MS);
+	pm_runtime_use_autosuspend(&client->dev);
+	pm_runtime_enable(&client->dev);
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0) {
+		dev_err(&client->dev, "Failed to register IIO device\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int ads1015_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct ads1015_data *data = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+
+	pm_runtime_disable(&client->dev);
+	pm_runtime_set_suspended(&client->dev);
+	pm_runtime_put_noidle(&client->dev);
+
+	/* power down single shot mode */
+	return ads1015_set_conv_mode(data, ADS1015_SINGLESHOT);
+}
+
+#ifdef CONFIG_PM
+static int ads1015_runtime_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct ads1015_data *data = iio_priv(indio_dev);
+
+	return ads1015_set_conv_mode(data, ADS1015_SINGLESHOT);
+}
+
+static int ads1015_runtime_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct ads1015_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = ads1015_set_conv_mode(data, ADS1015_CONTINUOUS);
+	if (!ret)
+		data->conv_invalid = true;
+
+	return ret;
+}
+#endif
+
+static const struct dev_pm_ops ads1015_pm_ops = {
+	SET_RUNTIME_PM_OPS(ads1015_runtime_suspend,
+			   ads1015_runtime_resume, NULL)
+};
+
+static const struct i2c_device_id ads1015_id[] = {
+	{"ads1015", ADS1015},
+	{"ads1115", ADS1115},
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, ads1015_id);
+
+static const struct of_device_id ads1015_of_match[] = {
+	{
+		.compatible = "ti,ads1015",
+		.data = (void *)ADS1015
+	},
+	{
+		.compatible = "ti,ads1115",
+		.data = (void *)ADS1115
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(of, ads1015_of_match);
+
+static struct i2c_driver ads1015_driver = {
+	.driver = {
+		.name = ADS1015_DRV_NAME,
+		.of_match_table = ads1015_of_match,
+		.pm = &ads1015_pm_ops,
+	},
+	.probe		= ads1015_probe,
+	.remove		= ads1015_remove,
+	.id_table	= ads1015_id,
+};
+
+module_i2c_driver(ads1015_driver);
+
+MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
+MODULE_DESCRIPTION("Texas Instruments ADS1015 ADC driver");
+MODULE_LICENSE("GPL v2");