[PATCH v4 0/1] iio: vcnl3020: add periodic mode, threshold options

[PATCH v4 0/1] iio: vcnl3020: add periodic mode, threshold options

[Ivan Mikhaylov]

Add periodic mode enablement, high/low threshold options.

Changes from v1:
 1. Remove changes for hwmon driver and changes affecting
vcnl3020 data structure.
 2. Add enable/disable periodic mode functions.

Changes from v2:
 1. Minor fixes from Jonathan's comments.

Changes from v3:
 1. add DMA safe buffer in vcnl3020_data and use it on bulk_read/write
    calls
 2. put vcnl3020_is_in_periodic_mode in vcnl3020_measure_proximity and
    vcnl3020_write_proxy_samp_freq
 3. add mutex instead of iio_claim in vcnl3020_write_proxy_samp_freq
 4. out_mutex -> err_unlock

Ivan Mikhaylov (1):
  iio: proximity: vcnl3020: add periodic mode

 drivers/iio/proximity/vcnl3020.c | 328 +++++++++++++++++++++++++++++--
 1 file changed, 313 insertions(+), 15 deletions(-)

-- 
2.31.1

[PATCH v4 1/1] iio: proximity: vcnl3020: add periodic mode

[Ivan Mikhaylov]

Add the possibility to run proximity sensor in periodic measurement
mode with thresholds.

Signed-off-by: Ivan Mikhaylov <i.mikhaylov@yadro.com>
---
 drivers/iio/proximity/vcnl3020.c | 328 +++++++++++++++++++++++++++++--
 1 file changed, 313 insertions(+), 15 deletions(-)

diff --git a/drivers/iio/proximity/vcnl3020.c b/drivers/iio/proximity/vcnl3020.c
index 43817f6b3086..edbc920635f1 100644
--- a/drivers/iio/proximity/vcnl3020.c
+++ b/drivers/iio/proximity/vcnl3020.c
@@ -3,7 +3,6 @@
  * Support for Vishay VCNL3020 proximity sensor on i2c bus.
  * Based on Vishay VCNL4000 driver code.
  *
- * TODO: interrupts.
  */
 
 #include <linux/module.h>
@@ -11,9 +10,10 @@
 #include <linux/err.h>
 #include <linux/delay.h>
 #include <linux/regmap.h>
+#include <linux/interrupt.h>
 
 #include <linux/iio/iio.h>
-#include <linux/iio/sysfs.h>
+#include <linux/iio/events.h>
 
 #define VCNL3020_PROD_ID	0x21
 
@@ -37,6 +37,21 @@
 					* measurement
 					*/
 
+/* Enables periodic proximity measurement */
+#define VCNL_PS_EN		BIT(1)
+
+/* Enables state machine and LP oscillator for self timed  measurements */
+#define VCNL_PS_SELFTIMED_EN	BIT(0)
+
+/* Bit masks for ICR */
+
+/* Enable interrupts on low or high thresholds */
+#define  VCNL_ICR_THRES_EN	BIT(1)
+
+/* Bit masks for ISR */
+#define VCNL_INT_TH_HI		BIT(0)	/* High threshold hit */
+#define VCNL_INT_TH_LOW		BIT(1)	/* Low threshold hit */
+
 #define VCNL_ON_DEMAND_TIMEOUT_US	100000
 #define VCNL_POLL_US			20000
 
@@ -63,6 +78,7 @@ struct vcnl3020_data {
 	struct device *dev;
 	u8 rev;
 	struct mutex lock;
+	__be16 buf ____cacheline_aligned;
 };
 
 /**
@@ -140,14 +156,31 @@ static int vcnl3020_init(struct vcnl3020_data *data)
 					       vcnl3020_led_current_property);
 };
 
+static bool vcnl3020_is_in_periodic_mode(struct vcnl3020_data *data)
+{
+	int rc;
+	unsigned int cmd;
+
+	rc = regmap_read(data->regmap, VCNL_COMMAND, &cmd);
+	if (rc)
+		return false;
+
+	return !!(cmd & VCNL_PS_SELFTIMED_EN);
+}
+
 static int vcnl3020_measure_proximity(struct vcnl3020_data *data, int *val)
 {
 	int rc;
 	unsigned int reg;
-	__be16 res;
 
 	mutex_lock(&data->lock);
 
+	/* Protect against event capture. */
+	if (vcnl3020_is_in_periodic_mode(data)) {
+		rc = -EBUSY;
+		goto err_unlock;
+	}
+
 	rc = regmap_write(data->regmap, VCNL_COMMAND, VCNL_PS_OD);
 	if (rc)
 		goto err_unlock;
@@ -163,12 +196,12 @@ static int vcnl3020_measure_proximity(struct vcnl3020_data *data, int *val)
 	}
 
 	/* high & low result bytes read */
-	rc = regmap_bulk_read(data->regmap, VCNL_PS_RESULT_HI, &res,
-			      sizeof(res));
+	rc = regmap_bulk_read(data->regmap, VCNL_PS_RESULT_HI, &data->buf,
+			      sizeof(data->buf));
 	if (rc)
 		goto err_unlock;
 
-	*val = be16_to_cpu(res);
+	*val = be16_to_cpu(data->buf);
 
 err_unlock:
 	mutex_unlock(&data->lock);
@@ -200,6 +233,15 @@ static int vcnl3020_write_proxy_samp_freq(struct vcnl3020_data *data, int val,
 {
 	unsigned int i;
 	int index = -1;
+	int rc;
+
+	mutex_lock(&data->lock);
+
+	/* Protect against event capture. */
+	if (vcnl3020_is_in_periodic_mode(data)) {
+		rc = -EBUSY;
+		goto err_unlock;
+	}
 
 	for (i = 0; i < ARRAY_SIZE(vcnl3020_prox_sampling_frequency); i++) {
 		if (val == vcnl3020_prox_sampling_frequency[i][0] &&
@@ -209,18 +251,229 @@ static int vcnl3020_write_proxy_samp_freq(struct vcnl3020_data *data, int val,
 		}
 	}
 
-	if (index < 0)
+	if (index < 0) {
+		rc = -EINVAL;
+		goto err_unlock;
+	}
+
+	rc = regmap_write(data->regmap, VCNL_PROXIMITY_RATE, index);
+
+err_unlock:
+	mutex_unlock(&data->lock);
+
+	return rc;
+}
+
+static bool vcnl3020_is_thr_enabled(struct vcnl3020_data *data)
+{
+	int rc;
+	unsigned int icr;
+
+	rc = regmap_read(data->regmap, VCNL_PS_ICR, &icr);
+	if (rc)
+		return false;
+
+	return !!(icr & VCNL_ICR_THRES_EN);
+}
+
+static int vcnl3020_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 rc;
+	struct vcnl3020_data *data = iio_priv(indio_dev);
+
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		switch (dir) {
+		case IIO_EV_DIR_RISING:
+			rc = regmap_bulk_read(data->regmap, VCNL_PS_HI_THR_HI,
+					      &data->buf, sizeof(data->buf));
+			if (rc < 0)
+				return rc;
+			*val = be16_to_cpu(data->buf);
+			return IIO_VAL_INT;
+		case IIO_EV_DIR_FALLING:
+			rc = regmap_bulk_read(data->regmap, VCNL_PS_LO_THR_HI,
+					      &data->buf, sizeof(data->buf));
+			if (rc < 0)
+				return rc;
+			*val = be16_to_cpu(data->buf);
+			return IIO_VAL_INT;
+		default:
+			return -EINVAL;
+		}
+	default:
 		return -EINVAL;
+	}
+}
+
+static int vcnl3020_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)
+{
+	int rc;
+	struct vcnl3020_data *data = iio_priv(indio_dev);
 
-	return regmap_write(data->regmap, VCNL_PROXIMITY_RATE, index);
+	mutex_lock(&data->lock);
+
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		switch (dir) {
+		case IIO_EV_DIR_RISING:
+			/* 16 bit word/ low * high */
+			data->buf = cpu_to_be16(val);
+			rc = regmap_bulk_write(data->regmap, VCNL_PS_HI_THR_HI,
+					       &data->buf, sizeof(data->buf));
+			if (rc < 0)
+				goto err_unlock;
+			rc = IIO_VAL_INT;
+			goto err_unlock;
+		case IIO_EV_DIR_FALLING:
+			data->buf = cpu_to_be16(val);
+			rc = regmap_bulk_write(data->regmap, VCNL_PS_LO_THR_HI,
+					       &data->buf, sizeof(data->buf));
+			if (rc < 0)
+				goto err_unlock;
+			rc = IIO_VAL_INT;
+			goto err_unlock;
+		default:
+			rc = -EINVAL;
+			goto err_unlock;
+		}
+	default:
+		rc = -EINVAL;
+		goto err_unlock;
+	}
+err_unlock:
+	mutex_unlock(&data->lock);
+
+	return rc;
 }
 
+static int vcnl3020_enable_periodic(struct iio_dev *indio_dev,
+				    struct vcnl3020_data *data)
+{
+	int rc;
+	int cmd;
+
+	mutex_lock(&data->lock);
+
+	/* Enable periodic measurement of proximity data. */
+	cmd = VCNL_PS_EN | VCNL_PS_SELFTIMED_EN;
+
+	rc = regmap_write(data->regmap, VCNL_COMMAND, cmd);
+	if (rc)
+		goto err_unlock;
+
+	/*
+	 * Enable interrupts on threshold, for proximity data by
+	 * default.
+	 */
+	rc = regmap_write(data->regmap, VCNL_PS_ICR, VCNL_ICR_THRES_EN);
+
+err_unlock:
+	mutex_unlock(&data->lock);
+
+	return rc;
+}
+
+static int vcnl3020_disable_periodic(struct iio_dev *indio_dev,
+				     struct vcnl3020_data *data)
+{
+	int rc;
+
+	mutex_lock(&data->lock);
+
+	rc = regmap_write(data->regmap, VCNL_COMMAND, 0);
+	if (rc)
+		goto err_unlock;
+
+	rc = regmap_write(data->regmap, VCNL_PS_ICR, 0);
+	if (rc)
+		goto err_unlock;
+
+	/* Clear interrupt flag bit */
+	rc = regmap_write(data->regmap, VCNL_ISR, 0);
+
+err_unlock:
+	mutex_unlock(&data->lock);
+
+	return rc;
+}
+
+static int vcnl3020_config_threshold(struct iio_dev *indio_dev, bool state)
+{
+	struct vcnl3020_data *data = iio_priv(indio_dev);
+
+	if (state) {
+		return vcnl3020_enable_periodic(indio_dev, data);
+	} else {
+		if (!vcnl3020_is_thr_enabled(data))
+			return 0;
+		return vcnl3020_disable_periodic(indio_dev, data);
+	}
+}
+
+static int vcnl3020_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)
+{
+	switch (chan->type) {
+	case IIO_PROXIMITY:
+		return vcnl3020_config_threshold(indio_dev, state);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int vcnl3020_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 vcnl3020_data *data = iio_priv(indio_dev);
+
+	switch (chan->type) {
+	case IIO_PROXIMITY:
+		return vcnl3020_is_thr_enabled(data);
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_event_spec vcnl3020_event_spec[] = {
+	{
+		.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_ENABLE),
+	},
+};
+
 static const struct iio_chan_spec vcnl3020_channels[] = {
 	{
 		.type = IIO_PROXIMITY,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 				      BIT(IIO_CHAN_INFO_SAMP_FREQ),
 		.info_mask_separate_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),
+		.event_spec = vcnl3020_event_spec,
+		.num_event_specs = ARRAY_SIZE(vcnl3020_event_spec),
 	},
 };
 
@@ -251,17 +504,11 @@ static int vcnl3020_write_raw(struct iio_dev *indio_dev,
 			      struct iio_chan_spec const *chan,
 			      int val, int val2, long mask)
 {
-	int rc;
 	struct vcnl3020_data *data = iio_priv(indio_dev);
 
 	switch (mask) {
 	case IIO_CHAN_INFO_SAMP_FREQ:
-		rc = iio_device_claim_direct_mode(indio_dev);
-		if (rc)
-			return rc;
-		rc = vcnl3020_write_proxy_samp_freq(data, val, val2);
-		iio_device_release_direct_mode(indio_dev);
-		return rc;
+		return vcnl3020_write_proxy_samp_freq(data, val, val2);
 	default:
 		return -EINVAL;
 	}
@@ -287,6 +534,10 @@ static const struct iio_info vcnl3020_info = {
 	.read_raw = vcnl3020_read_raw,
 	.write_raw = vcnl3020_write_raw,
 	.read_avail = vcnl3020_read_avail,
+	.read_event_value = vcnl3020_read_event,
+	.write_event_value = vcnl3020_write_event,
+	.read_event_config = vcnl3020_read_event_config,
+	.write_event_config = vcnl3020_write_event_config,
 };
 
 static const struct regmap_config vcnl3020_regmap_config = {
@@ -295,6 +546,40 @@ static const struct regmap_config vcnl3020_regmap_config = {
 	.max_register	= VCNL_PS_MOD_ADJ,
 };
 
+static irqreturn_t vcnl3020_handle_irq_thread(int irq, void *p)
+{
+	struct iio_dev *indio_dev = p;
+	struct vcnl3020_data *data = iio_priv(indio_dev);
+	unsigned int isr;
+	int rc;
+
+	rc = regmap_read(data->regmap, VCNL_ISR, &isr);
+	if (rc) {
+		dev_err(data->dev, "Error (%d) reading reg (0x%x)\n",
+			rc, VCNL_ISR);
+		return IRQ_HANDLED;
+	}
+
+	if (isr & VCNL_ICR_THRES_EN) {
+		iio_push_event(indio_dev,
+			       IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY,
+						    1,
+						    IIO_EV_TYPE_THRESH,
+						    IIO_EV_DIR_RISING),
+			       iio_get_time_ns(indio_dev));
+
+		rc = regmap_write(data->regmap, VCNL_ISR,
+				  isr & VCNL_ICR_THRES_EN);
+		if (rc)
+			dev_err(data->dev, "Error (%d) writing in reg (0x%x)\n",
+				rc, VCNL_ISR);
+	} else {
+		return IRQ_NONE;
+	}
+
+	return IRQ_HANDLED;
+}
+
 static int vcnl3020_probe(struct i2c_client *client)
 {
 	struct vcnl3020_data *data;
@@ -327,6 +612,19 @@ static int vcnl3020_probe(struct i2c_client *client)
 	indio_dev->name = "vcnl3020";
 	indio_dev->modes = INDIO_DIRECT_MODE;
 
+	if (client->irq) {
+		rc = devm_request_threaded_irq(&client->dev, client->irq,
+					       NULL, vcnl3020_handle_irq_thread,
+					       IRQF_ONESHOT, indio_dev->name,
+					       indio_dev);
+		if (rc) {
+			dev_err(&client->dev,
+				"Error (%d) irq request failed (%u)\n", rc,
+				client->irq);
+			return rc;
+		}
+	}
+
 	return devm_iio_device_register(&client->dev, indio_dev);
 }
 
-- 
2.31.1

Re: [PATCH v4 1/1] iio: proximity: vcnl3020: add periodic mode

[Jonathan Cameron]

On Thu, 15 Jul 2021 15:47:28 +0300
Ivan Mikhaylov <i.mikhaylov@yadro.com> wrote:

> Add the possibility to run proximity sensor in periodic measurement
> mode with thresholds.
> 
> Signed-off-by: Ivan Mikhaylov <i.mikhaylov@yadro.com>

Hi Ivan,

The content here is fine, but a result of earlier reviews is that you have
included a couple of fixes / improvements that aren't directly related
to the main topic of this patch, or indeed mentioned in the description.

Those need to pulled out as precusors to the main patch.  The bulk
read one 'might' be a bug fix for some odd hardware combination for
example so we need to make it easy to spot.

Thanks,

Jonathan

> ---
>  drivers/iio/proximity/vcnl3020.c | 328 +++++++++++++++++++++++++++++--
>  1 file changed, 313 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/iio/proximity/vcnl3020.c b/drivers/iio/proximity/vcnl3020.c
> index 43817f6b3086..edbc920635f1 100644
> --- a/drivers/iio/proximity/vcnl3020.c
> +++ b/drivers/iio/proximity/vcnl3020.c
> @@ -3,7 +3,6 @@
>   * Support for Vishay VCNL3020 proximity sensor on i2c bus.
>   * Based on Vishay VCNL4000 driver code.
>   *

Totally trivial, but good to clear out this blank line as well!

> - * TODO: interrupts.
>   */
>  
>  #include <linux/module.h>
> @@ -11,9 +10,10 @@
>  #include <linux/err.h>
>  #include <linux/delay.h>
>  #include <linux/regmap.h>
> +#include <linux/interrupt.h>
>  
>  #include <linux/iio/iio.h>
> -#include <linux/iio/sysfs.h>
> +#include <linux/iio/events.h>
>  
>  #define VCNL3020_PROD_ID	0x21
>  
> @@ -37,6 +37,21 @@
>  					* measurement
>  					*/
>  
> +/* Enables periodic proximity measurement */
> +#define VCNL_PS_EN		BIT(1)
> +
> +/* Enables state machine and LP oscillator for self timed  measurements */
> +#define VCNL_PS_SELFTIMED_EN	BIT(0)
> +
> +/* Bit masks for ICR */
> +
> +/* Enable interrupts on low or high thresholds */
> +#define  VCNL_ICR_THRES_EN	BIT(1)
> +
> +/* Bit masks for ISR */
> +#define VCNL_INT_TH_HI		BIT(0)	/* High threshold hit */
> +#define VCNL_INT_TH_LOW		BIT(1)	/* Low threshold hit */
> +
>  #define VCNL_ON_DEMAND_TIMEOUT_US	100000
>  #define VCNL_POLL_US			20000
>  
> @@ -63,6 +78,7 @@ struct vcnl3020_data {
>  	struct device *dev;
>  	u8 rev;
>  	struct mutex lock;
> +	__be16 buf ____cacheline_aligned;
>  };
>  
>  /**
> @@ -140,14 +156,31 @@ static int vcnl3020_init(struct vcnl3020_data *data)
>  					       vcnl3020_led_current_property);
>  };
>  
> +static bool vcnl3020_is_in_periodic_mode(struct vcnl3020_data *data)
> +{
> +	int rc;
> +	unsigned int cmd;
> +
> +	rc = regmap_read(data->regmap, VCNL_COMMAND, &cmd);
> +	if (rc)

A little inelegant to hide the error.

> +		return false;
> +
> +	return !!(cmd & VCNL_PS_SELFTIMED_EN);
> +}
> +
>  static int vcnl3020_measure_proximity(struct vcnl3020_data *data, int *val)
>  {
>  	int rc;
>  	unsigned int reg;
> -	__be16 res;
>  
>  	mutex_lock(&data->lock);
>  
> +	/* Protect against event capture. */
> +	if (vcnl3020_is_in_periodic_mode(data)) {
> +		rc = -EBUSY;
> +		goto err_unlock;
> +	}
> +
>  	rc = regmap_write(data->regmap, VCNL_COMMAND, VCNL_PS_OD);
>  	if (rc)
>  		goto err_unlock;
> @@ -163,12 +196,12 @@ static int vcnl3020_measure_proximity(struct vcnl3020_data *data, int *val)
>  	}
>  
>  	/* high & low result bytes read */
> -	rc = regmap_bulk_read(data->regmap, VCNL_PS_RESULT_HI, &res,
> -			      sizeof(res));
> +	rc = regmap_bulk_read(data->regmap, VCNL_PS_RESULT_HI, &data->buf,
> +			      sizeof(data->buf));

This is good to have as discussed, but it's not related to the rest of the patch.
Please break this out to a precursor patch as it will make it easier to review
what is going on here.

>  	if (rc)
>  		goto err_unlock;
>  
> -	*val = be16_to_cpu(res);
> +	*val = be16_to_cpu(data->buf);
>  
>  err_unlock:
>  	mutex_unlock(&data->lock);
> @@ -200,6 +233,15 @@ static int vcnl3020_write_proxy_samp_freq(struct vcnl3020_data *data, int val,
>  {
>  	unsigned int i;
>  	int index = -1;
> +	int rc;
> +
> +	mutex_lock(&data->lock);
> +
> +	/* Protect against event capture. */
> +	if (vcnl3020_is_in_periodic_mode(data)) {
> +		rc = -EBUSY;
> +		goto err_unlock;
> +	}
>  
>  	for (i = 0; i < ARRAY_SIZE(vcnl3020_prox_sampling_frequency); i++) {
>  		if (val == vcnl3020_prox_sampling_frequency[i][0] &&
> @@ -209,18 +251,229 @@ static int vcnl3020_write_proxy_samp_freq(struct vcnl3020_data *data, int val,
>  		}
>  	}
>  
> -	if (index < 0)
> +	if (index < 0) {
> +		rc = -EINVAL;
> +		goto err_unlock;
> +	}
> +
> +	rc = regmap_write(data->regmap, VCNL_PROXIMITY_RATE, index);
> +
> +err_unlock:
> +	mutex_unlock(&data->lock);
> +
> +	return rc;
> +}
> +
> +static bool vcnl3020_is_thr_enabled(struct vcnl3020_data *data)
> +{
> +	int rc;
> +	unsigned int icr;
> +
> +	rc = regmap_read(data->regmap, VCNL_PS_ICR, &icr);
> +	if (rc)
> +		return false;
> +
> +	return !!(icr & VCNL_ICR_THRES_EN);
> +}
> +
> +static int vcnl3020_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 rc;
> +	struct vcnl3020_data *data = iio_priv(indio_dev);
> +
> +	switch (info) {
> +	case IIO_EV_INFO_VALUE:
> +		switch (dir) {
> +		case IIO_EV_DIR_RISING:
> +			rc = regmap_bulk_read(data->regmap, VCNL_PS_HI_THR_HI,
> +					      &data->buf, sizeof(data->buf));
> +			if (rc < 0)
> +				return rc;
> +			*val = be16_to_cpu(data->buf);
> +			return IIO_VAL_INT;
> +		case IIO_EV_DIR_FALLING:
> +			rc = regmap_bulk_read(data->regmap, VCNL_PS_LO_THR_HI,
> +					      &data->buf, sizeof(data->buf));
> +			if (rc < 0)
> +				return rc;
> +			*val = be16_to_cpu(data->buf);
> +			return IIO_VAL_INT;
> +		default:
> +			return -EINVAL;
> +		}
> +	default:
>  		return -EINVAL;
> +	}
> +}
> +
> +static int vcnl3020_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)
> +{
> +	int rc;
> +	struct vcnl3020_data *data = iio_priv(indio_dev);
>  
> -	return regmap_write(data->regmap, VCNL_PROXIMITY_RATE, index);
> +	mutex_lock(&data->lock);
> +
> +	switch (info) {
> +	case IIO_EV_INFO_VALUE:
> +		switch (dir) {
> +		case IIO_EV_DIR_RISING:
> +			/* 16 bit word/ low * high */
> +			data->buf = cpu_to_be16(val);
> +			rc = regmap_bulk_write(data->regmap, VCNL_PS_HI_THR_HI,
> +					       &data->buf, sizeof(data->buf));
> +			if (rc < 0)
> +				goto err_unlock;
> +			rc = IIO_VAL_INT;
> +			goto err_unlock;
> +		case IIO_EV_DIR_FALLING:
> +			data->buf = cpu_to_be16(val);
> +			rc = regmap_bulk_write(data->regmap, VCNL_PS_LO_THR_HI,
> +					       &data->buf, sizeof(data->buf));
> +			if (rc < 0)
> +				goto err_unlock;
> +			rc = IIO_VAL_INT;
> +			goto err_unlock;
> +		default:
> +			rc = -EINVAL;
> +			goto err_unlock;
> +		}
> +	default:
> +		rc = -EINVAL;
> +		goto err_unlock;
> +	}
> +err_unlock:
> +	mutex_unlock(&data->lock);
> +
> +	return rc;
>  }
>  
> +static int vcnl3020_enable_periodic(struct iio_dev *indio_dev,
> +				    struct vcnl3020_data *data)
> +{
> +	int rc;
> +	int cmd;
> +
> +	mutex_lock(&data->lock);
> +
> +	/* Enable periodic measurement of proximity data. */
> +	cmd = VCNL_PS_EN | VCNL_PS_SELFTIMED_EN;
> +
> +	rc = regmap_write(data->regmap, VCNL_COMMAND, cmd);
> +	if (rc)
> +		goto err_unlock;
> +
> +	/*
> +	 * Enable interrupts on threshold, for proximity data by
> +	 * default.
> +	 */
> +	rc = regmap_write(data->regmap, VCNL_PS_ICR, VCNL_ICR_THRES_EN);
> +
> +err_unlock:
> +	mutex_unlock(&data->lock);
> +
> +	return rc;
> +}
> +
> +static int vcnl3020_disable_periodic(struct iio_dev *indio_dev,
> +				     struct vcnl3020_data *data)
> +{
> +	int rc;
> +
> +	mutex_lock(&data->lock);
> +
> +	rc = regmap_write(data->regmap, VCNL_COMMAND, 0);
> +	if (rc)
> +		goto err_unlock;
> +
> +	rc = regmap_write(data->regmap, VCNL_PS_ICR, 0);
> +	if (rc)
> +		goto err_unlock;
> +
> +	/* Clear interrupt flag bit */
> +	rc = regmap_write(data->regmap, VCNL_ISR, 0);
> +
> +err_unlock:
> +	mutex_unlock(&data->lock);
> +
> +	return rc;
> +}
> +
> +static int vcnl3020_config_threshold(struct iio_dev *indio_dev, bool state)
> +{
> +	struct vcnl3020_data *data = iio_priv(indio_dev);
> +
> +	if (state) {
> +		return vcnl3020_enable_periodic(indio_dev, data);
> +	} else {
> +		if (!vcnl3020_is_thr_enabled(data))
> +			return 0;
> +		return vcnl3020_disable_periodic(indio_dev, data);
> +	}
> +}
> +
> +static int vcnl3020_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)
> +{
> +	switch (chan->type) {
> +	case IIO_PROXIMITY:
> +		return vcnl3020_config_threshold(indio_dev, state);
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static int vcnl3020_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 vcnl3020_data *data = iio_priv(indio_dev);
> +
> +	switch (chan->type) {
> +	case IIO_PROXIMITY:
> +		return vcnl3020_is_thr_enabled(data);
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static const struct iio_event_spec vcnl3020_event_spec[] = {
> +	{
> +		.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_ENABLE),
> +	},
> +};
> +
>  static const struct iio_chan_spec vcnl3020_channels[] = {
>  	{
>  		.type = IIO_PROXIMITY,
>  		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>  				      BIT(IIO_CHAN_INFO_SAMP_FREQ),
>  		.info_mask_separate_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),
> +		.event_spec = vcnl3020_event_spec,
> +		.num_event_specs = ARRAY_SIZE(vcnl3020_event_spec),
>  	},
>  };
>  
> @@ -251,17 +504,11 @@ static int vcnl3020_write_raw(struct iio_dev *indio_dev,
>  			      struct iio_chan_spec const *chan,
>  			      int val, int val2, long mask)
>  {
> -	int rc;
>  	struct vcnl3020_data *data = iio_priv(indio_dev);
>  
>  	switch (mask) {
>  	case IIO_CHAN_INFO_SAMP_FREQ:
> -		rc = iio_device_claim_direct_mode(indio_dev);
> -		if (rc)
> -			return rc;
> -		rc = vcnl3020_write_proxy_samp_freq(data, val, val2);
> -		iio_device_release_direct_mode(indio_dev);
> -		return rc;
> +		return vcnl3020_write_proxy_samp_freq(data, val, val2);

This is another thing that is not related (I think) to the main change
here so should be in a separate patch.

>  	default:
>  		return -EINVAL;
>  	}
> @@ -287,6 +534,10 @@ static const struct iio_info vcnl3020_info = {
>  	.read_raw = vcnl3020_read_raw,
>  	.write_raw = vcnl3020_write_raw,
>  	.read_avail = vcnl3020_read_avail,
> +	.read_event_value = vcnl3020_read_event,
> +	.write_event_value = vcnl3020_write_event,
> +	.read_event_config = vcnl3020_read_event_config,
> +	.write_event_config = vcnl3020_write_event_config,
>  };
>  
>  static const struct regmap_config vcnl3020_regmap_config = {
> @@ -295,6 +546,40 @@ static const struct regmap_config vcnl3020_regmap_config = {
>  	.max_register	= VCNL_PS_MOD_ADJ,
>  };
>  
> +static irqreturn_t vcnl3020_handle_irq_thread(int irq, void *p)
> +{
> +	struct iio_dev *indio_dev = p;
> +	struct vcnl3020_data *data = iio_priv(indio_dev);
> +	unsigned int isr;
> +	int rc;
> +
> +	rc = regmap_read(data->regmap, VCNL_ISR, &isr);
> +	if (rc) {
> +		dev_err(data->dev, "Error (%d) reading reg (0x%x)\n",
> +			rc, VCNL_ISR);
> +		return IRQ_HANDLED;
> +	}
> +
> +	if (isr & VCNL_ICR_THRES_EN) {
> +		iio_push_event(indio_dev,
> +			       IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY,
> +						    1,
> +						    IIO_EV_TYPE_THRESH,
> +						    IIO_EV_DIR_RISING),
> +			       iio_get_time_ns(indio_dev));
> +
> +		rc = regmap_write(data->regmap, VCNL_ISR,
> +				  isr & VCNL_ICR_THRES_EN);
> +		if (rc)
> +			dev_err(data->dev, "Error (%d) writing in reg (0x%x)\n",
> +				rc, VCNL_ISR);
> +	} else {
> +		return IRQ_NONE;
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
>  static int vcnl3020_probe(struct i2c_client *client)
>  {
>  	struct vcnl3020_data *data;
> @@ -327,6 +612,19 @@ static int vcnl3020_probe(struct i2c_client *client)
>  	indio_dev->name = "vcnl3020";
>  	indio_dev->modes = INDIO_DIRECT_MODE;
>  
> +	if (client->irq) {
> +		rc = devm_request_threaded_irq(&client->dev, client->irq,
> +					       NULL, vcnl3020_handle_irq_thread,
> +					       IRQF_ONESHOT, indio_dev->name,
> +					       indio_dev);
> +		if (rc) {
> +			dev_err(&client->dev,
> +				"Error (%d) irq request failed (%u)\n", rc,
> +				client->irq);
> +			return rc;
> +		}
> +	}
> +
>  	return devm_iio_device_register(&client->dev, indio_dev);
>  }
>