[PATCH v2 5/7] iio: light: vcnl4000: Add debounce count for vcnl4040/4200

[Astrid Rost <astrid.rost@axis.com>]

Add read/write attribute for proximity and illumination debounce-count
and read attribute for available debounce-counts.
The debounce-count is set in the interrupt persistence flags
(PS_PERS and ALS_PERS). An interrupt will not be asserted if the raw
value is not over (or lower) than the threshold for the set
continued refresh times.
This is supported for vcnl4040 vcnl4200.

Signed-off-by: Astrid Rost <astrid.rost@axis.com>
---
 drivers/iio/light/vcnl4000.c | 156 ++++++++++++++++++++++++++++++++++-
 1 file changed, 152 insertions(+), 4 deletions(-)

diff --git a/drivers/iio/light/vcnl4000.c b/drivers/iio/light/vcnl4000.c
index 68eea686b2dc..b8ce4ed6b0bb 100644
--- a/drivers/iio/light/vcnl4000.c
+++ b/drivers/iio/light/vcnl4000.c
@@ -84,8 +84,10 @@
 #define VCNL4040_ALS_CONF_ALS_SHUTDOWN	BIT(0)
 #define VCNL4040_ALS_CONF_IT		GENMASK(7, 6) /* Ambient integration time */
 #define VCNL4040_ALS_CONF_INT_EN	BIT(1) /* Ambient light Interrupt enable */
+#define VCNL4040_ALS_CONF_PERS	GENMASK(3, 2) /* Ambient interrupt persistence setting */
 #define VCNL4040_PS_CONF1_PS_SHUTDOWN	BIT(0)
 #define VCNL4040_PS_CONF2_PS_IT	GENMASK(3, 1) /* Proximity integration time */
+#define VCNL4040_CONF1_PS_PERS	GENMASK(5, 4) /* Proximity interrupt persistence setting */
 #define VCNL4040_PS_CONF2_PS_INT	GENMASK(9, 8) /* Proximity interrupt mode */
 #define VCNL4040_PS_IF_AWAY		BIT(8) /* Proximity event cross low threshold */
 #define VCNL4040_PS_IF_CLOSE		BIT(9) /* Proximity event cross high threshold */
@@ -153,6 +155,9 @@ static const int vcnl4200_als_it_times[][2] = {
 	{0, 400000},
 };
 
+static const int vcnl4040_als_debounce_count[] = {1, 2, 4, 8};
+static const int vcnl4040_ps_debounce_count[] = {1, 2, 3, 4};
+
 #define VCNL4000_SLEEP_DELAY_MS	2000 /* before we enter pm_runtime_suspend */
 
 enum vcnl4000_device_ids {
@@ -680,6 +685,106 @@ static ssize_t vcnl4040_write_ps_it(struct vcnl4000_data *data, int val)
 	return ret;
 }
 
+static ssize_t vcnl4040_read_als_debounce_count(struct vcnl4000_data *data, int *val)
+{
+	int ret;
+
+	ret = i2c_smbus_read_word_data(data->client, VCNL4200_AL_CONF);
+	if (ret < 0)
+		return ret;
+
+	ret = FIELD_GET(VCNL4040_ALS_CONF_PERS, ret);
+
+	if (ret >= ARRAY_SIZE(vcnl4200_als_it_times))
+		return -EINVAL;
+
+	*val = vcnl4040_als_debounce_count[ret];
+
+	return ret;
+}
+
+static ssize_t vcnl4040_write_als_debounce_count(struct vcnl4000_data *data, int val)
+{
+	unsigned int i;
+	int ret, index = -1;
+	u16 regval;
+
+	for (i = 0; i < ARRAY_SIZE(vcnl4040_als_debounce_count); i++) {
+		if (val == vcnl4040_als_debounce_count[i]) {
+			index = i;
+			break;
+		}
+	}
+
+	if (index < 0)
+		return -EINVAL;
+
+	mutex_lock(&data->vcnl4000_lock);
+
+	ret = i2c_smbus_read_word_data(data->client, VCNL4200_AL_CONF);
+	if (ret < 0)
+		goto out;
+
+	regval = (ret & ~VCNL4040_ALS_CONF_PERS) |
+	    FIELD_PREP(VCNL4040_ALS_CONF_PERS, index);
+	ret = i2c_smbus_write_word_data(data->client, VCNL4200_AL_CONF,
+					regval);
+
+out:
+	mutex_unlock(&data->vcnl4000_lock);
+	return ret;
+}
+
+static ssize_t vcnl4040_read_ps_debounce_count(struct vcnl4000_data *data, int *val)
+{
+	int ret;
+
+	ret = i2c_smbus_read_word_data(data->client, VCNL4200_PS_CONF1);
+	if (ret < 0)
+		return ret;
+
+	ret = FIELD_GET(VCNL4040_CONF1_PS_PERS, ret);
+
+	if (ret >= ARRAY_SIZE(vcnl4200_ps_it_times))
+		return -EINVAL;
+
+	*val = vcnl4040_ps_debounce_count[ret];
+
+	return ret;
+}
+
+static ssize_t vcnl4040_write_ps_debounce_count(struct vcnl4000_data *data, int val)
+{
+	unsigned int i;
+	int ret, index = -1;
+	u16 regval;
+
+	for (i = 0; i < ARRAY_SIZE(vcnl4040_ps_debounce_count); i++) {
+		if (val == vcnl4040_ps_debounce_count[i]) {
+			index = i;
+			break;
+		}
+	}
+
+	if (index < 0)
+		return -EINVAL;
+
+	mutex_lock(&data->vcnl4000_lock);
+
+	ret = i2c_smbus_read_word_data(data->client, VCNL4200_PS_CONF1);
+	if (ret < 0)
+		goto out;
+
+	regval = (ret & ~VCNL4040_CONF1_PS_PERS) |
+	    FIELD_PREP(VCNL4040_CONF1_PS_PERS, index);
+	ret = i2c_smbus_write_word_data(data->client, VCNL4200_PS_CONF1,
+					regval);
+
+out:
+	mutex_unlock(&data->vcnl4000_lock);
+	return ret;
+}
+
 static int vcnl4000_read_raw(struct iio_dev *indio_dev,
 				struct iio_chan_spec const *chan,
 				int *val, int *val2, long mask)
@@ -730,6 +835,21 @@ static int vcnl4000_read_raw(struct iio_dev *indio_dev,
 		if (ret < 0)
 			return ret;
 		return IIO_VAL_INT_PLUS_MICRO;
+	case IIO_CHAN_INFO_DEBOUNCE_COUNT:
+		switch (chan->type) {
+		case IIO_LIGHT:
+			ret = vcnl4040_read_als_debounce_count(data, val);
+			break;
+		case IIO_PROXIMITY:
+			ret = vcnl4040_read_ps_debounce_count(data, val);
+			break;
+		default:
+			return -EINVAL;
+		}
+		if (ret < 0)
+			return ret;
+		return IIO_VAL_INT;
+
 	default:
 		return -EINVAL;
 	}
@@ -753,6 +873,15 @@ static int vcnl4040_write_raw(struct iio_dev *indio_dev,
 		default:
 			return -EINVAL;
 		}
+	case IIO_CHAN_INFO_DEBOUNCE_COUNT:
+		switch (chan->type) {
+		case IIO_LIGHT:
+			return vcnl4040_write_als_debounce_count(data, val);
+		case IIO_PROXIMITY:
+			return vcnl4040_write_ps_debounce_count(data, val);
+		default:
+			return -EINVAL;
+		}
 	default:
 		return -EINVAL;
 	}
@@ -791,6 +920,21 @@ static int vcnl4040_read_avail(struct iio_dev *indio_dev,
 		}
 		*type = IIO_VAL_INT_PLUS_MICRO;
 		return IIO_AVAIL_LIST;
+	case IIO_CHAN_INFO_DEBOUNCE_COUNT:
+		switch (chan->type) {
+		case IIO_LIGHT:
+			*vals = (int *)vcnl4040_als_debounce_count;
+			*length = ARRAY_SIZE(vcnl4040_als_debounce_count);
+			break;
+		case IIO_PROXIMITY:
+			*vals = (int *)vcnl4040_ps_debounce_count;
+			*length = ARRAY_SIZE(vcnl4040_ps_debounce_count);
+			break;
+		default:
+			return -EINVAL;
+		}
+		*type = IIO_VAL_INT;
+		return IIO_AVAIL_LIST;
 	default:
 		return -EINVAL;
 	}
@@ -1504,15 +1648,19 @@ static const struct iio_chan_spec vcnl4040_channels[] = {
 		.type = IIO_LIGHT,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 			BIT(IIO_CHAN_INFO_SCALE) |
-			BIT(IIO_CHAN_INFO_INT_TIME),
-		.info_mask_separate_available = BIT(IIO_CHAN_INFO_INT_TIME),
+			BIT(IIO_CHAN_INFO_INT_TIME) |
+			BIT(IIO_CHAN_INFO_DEBOUNCE_COUNT),
+		.info_mask_separate_available = BIT(IIO_CHAN_INFO_INT_TIME) |
+			BIT(IIO_CHAN_INFO_DEBOUNCE_COUNT),
 		.event_spec = vcnl4000_event_spec,
 		.num_event_specs = ARRAY_SIZE(vcnl4000_event_spec),
 	}, {
 		.type = IIO_PROXIMITY,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
-			BIT(IIO_CHAN_INFO_INT_TIME),
-		.info_mask_separate_available = BIT(IIO_CHAN_INFO_INT_TIME),
+			BIT(IIO_CHAN_INFO_INT_TIME) |
+			BIT(IIO_CHAN_INFO_DEBOUNCE_COUNT),
+		.info_mask_separate_available = BIT(IIO_CHAN_INFO_INT_TIME) |
+			BIT(IIO_CHAN_INFO_DEBOUNCE_COUNT),
 		.ext_info = vcnl4000_ext_info,
 		.event_spec = vcnl4040_event_spec,
 		.num_event_specs = ARRAY_SIZE(vcnl4040_event_spec),
-- 
2.30.2