1 files changed, 407 insertions, 2 deletions

diff --git a/drivers/iio/adc/ti-ads1015.c b/drivers/iio/adc/ti-ads1015.c
index 14c573175f8e..d1210024f6bc 100644
--- a/drivers/iio/adc/ti-ads1015.c
+++ b/drivers/iio/adc/ti-ads1015.c
@@ -17,6 +17,7 @@
 #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>
@@ -28,6 +29,7 @@
 #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>
@@ -36,17 +38,38 @@
 
 #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(2)
+#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
@@ -89,6 +112,30 @@ 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,						\
@@ -105,6 +152,8 @@ static int ads1015_fullscale_range[] = {
 		.shift = 4,					\
 		.endianness = IIO_CPU,				\
 	},							\
+	.event_spec = ads1015_events,				\
+	.num_event_specs = ARRAY_SIZE(ads1015_events),		\
 	.datasheet_name = "AIN"#_chan,				\
 }
 
@@ -126,6 +175,8 @@ static int ads1015_fullscale_range[] = {
 		.shift = 4,					\
 		.endianness = IIO_CPU,				\
 	},							\
+	.event_spec = ads1015_events,				\
+	.num_event_specs = ARRAY_SIZE(ads1015_events),		\
 	.datasheet_name = "AIN"#_chan"-AIN"#_chan2,		\
 }
 
@@ -144,6 +195,8 @@ static int ads1015_fullscale_range[] = {
 		.storagebits = 16,				\
 		.endianness = IIO_CPU,				\
 	},							\
+	.event_spec = ads1015_events,				\
+	.num_event_specs = ARRAY_SIZE(ads1015_events),		\
 	.datasheet_name = "AIN"#_chan,				\
 }
 
@@ -164,9 +217,17 @@ static int ads1015_fullscale_range[] = {
 		.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;
 	/*
@@ -176,6 +237,10 @@ struct ads1015_data {
 	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
@@ -185,15 +250,41 @@ struct ads1015_data {
 	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)
 {
-	return (reg == ADS1015_CFG_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_CFG_REG,
+	.max_register = ADS1015_HI_THRESH_REG,
 	.writeable_reg = ads1015_is_writeable_reg,
 };
 
@@ -258,6 +349,14 @@ int ads1015_get_adc_result(struct ads1015_data *data, int chan, int *val)
 	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);
 
 	ret = regmap_write(data->regmap, ADS1015_CFG_REG, cfg);
@@ -356,6 +455,12 @@ static int ads1015_read_raw(struct iio_dev *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;
@@ -421,8 +526,254 @@ static int ads1015_write_raw(struct iio_dev *indio_dev,
 	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);
 }
 
@@ -473,6 +824,10 @@ static const struct iio_info ads1015_info = {
 	.driver_module	= THIS_MODULE,
 	.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,
 };
 
@@ -480,6 +835,10 @@ static const struct iio_info ads1115_info = {
 	.driver_module	= THIS_MODULE,
 	.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,
 };
 
@@ -583,6 +942,7 @@ static int ads1015_probe(struct i2c_client *client,
 	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)
@@ -617,6 +977,18 @@ static int ads1015_probe(struct i2c_client *client,
 		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);
 
@@ -634,6 +1006,39 @@ static int ads1015_probe(struct i2c_client *client,
 		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;
+			break;
+		case IRQF_TRIGGER_HIGH:
+			cfg_comp |= ADS1015_CFG_COMP_POL_HIGH;
+			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;