[PATCH v3 7/7] iio: light: vcnl4000: Add calibration bias for 4040/4200

From: Astrid Rost
Date: Wed May 17 2023 - 11:14:36 EST


The calibration bias is setting the LED current to change
the detection distance.
Add read/write attribute for proximity calibration bias and read
attribute for available values.
This is supported for vcnl4040 and vcnl4200.

Signed-off-by: Astrid Rost <astrid.rost@xxxxxxxx>
---
drivers/iio/light/vcnl4000.c | 98 ++++++++++++++++++++++++++++++++++--
1 file changed, 95 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/light/vcnl4000.c b/drivers/iio/light/vcnl4000.c
index 631ed6aa26b2..0a6e38e56a7c 100644
--- a/drivers/iio/light/vcnl4000.c
+++ b/drivers/iio/light/vcnl4000.c
@@ -91,6 +91,7 @@
#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_CONF3_MPS GENMASK(6, 5) /* Proximity multi pulse number */
+#define VCNL4040_PS_MS_LED_I GENMASK(10, 8) /* Proximity current */
#define VCNL4040_PS_IF_AWAY BIT(8) /* Proximity event cross low threshold */
#define VCNL4040_PS_IF_CLOSE BIT(9) /* Proximity event cross high threshold */
#define VCNL4040_ALS_RISING BIT(12) /* Ambient Light cross high threshold */
@@ -156,6 +157,18 @@ static const int vcnl4200_als_it_times[][2] = {
{0, 200000},
{0, 400000},
};
+
+static const int vcnl4040_ps_calibbias_ua[][2] = {
+ {0, 50000},
+ {0, 75000},
+ {0, 100000},
+ {0, 120000},
+ {0, 140000},
+ {0, 160000},
+ {0, 180000},
+ {0, 200000},
+};
+
static const int vcnl4040_als_persistence[] = {1, 2, 4, 8};
static const int vcnl4040_ps_persistence[] = {1, 2, 3, 4};
static const int vcnl4040_ps_oversampling_ratio[] = {1, 2, 4, 8};
@@ -831,6 +844,57 @@ static ssize_t vcnl4040_write_ps_oversampling_ratio(struct vcnl4000_data *data,
return ret;
}

+static ssize_t vcnl4040_read_ps_calibbias(struct vcnl4000_data *data, int *val, int *val2)
+{
+ int ret;
+
+ ret = i2c_smbus_read_word_data(data->client, VCNL4200_PS_CONF3);
+ if (ret < 0)
+ return ret;
+
+ ret = FIELD_GET(VCNL4040_PS_MS_LED_I, ret);
+
+ if (ret >= ARRAY_SIZE(vcnl4040_ps_calibbias_ua))
+ return -EINVAL;
+
+ *val = vcnl4040_ps_calibbias_ua[ret][0];
+ *val2 = vcnl4040_ps_calibbias_ua[ret][1];
+
+ return ret;
+}
+
+static ssize_t vcnl4040_write_ps_calibbias(struct vcnl4000_data *data, int val)
+{
+ unsigned int i;
+ int ret, index = -1;
+ u16 regval;
+
+ for (i = 0; i < ARRAY_SIZE(vcnl4040_ps_calibbias_ua); i++) {
+ if (val == vcnl4040_ps_calibbias_ua[i][1]) {
+ index = i;
+ break;
+ }
+ }
+
+ if (index < 0)
+ return -EINVAL;
+
+ mutex_lock(&data->vcnl4000_lock);
+
+ ret = i2c_smbus_read_word_data(data->client, VCNL4200_PS_CONF3);
+ if (ret < 0)
+ goto out;
+
+ regval = (ret & ~VCNL4040_PS_MS_LED_I) |
+ FIELD_PREP(VCNL4040_PS_MS_LED_I, index);
+ ret = i2c_smbus_write_word_data(data->client, VCNL4200_PS_CONF3,
+ 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)
@@ -891,7 +955,16 @@ static int vcnl4000_read_raw(struct iio_dev *indio_dev,
default:
return -EINVAL;
}
-
+ case IIO_CHAN_INFO_CALIBBIAS:
+ switch (chan->type) {
+ case IIO_PROXIMITY:
+ ret = vcnl4040_read_ps_calibbias(data, val, val2);
+ if (ret < 0)
+ return ret;
+ return IIO_VAL_INT_PLUS_MICRO;
+ default:
+ return -EINVAL;
+ }
default:
return -EINVAL;
}
@@ -922,6 +995,13 @@ static int vcnl4040_write_raw(struct iio_dev *indio_dev,
default:
return -EINVAL;
}
+ case IIO_CHAN_INFO_CALIBBIAS:
+ switch (chan->type) {
+ case IIO_PROXIMITY:
+ return vcnl4040_write_ps_calibbias(data, val2);
+ default:
+ return -EINVAL;
+ }
default:
return -EINVAL;
}
@@ -961,6 +1041,16 @@ static int vcnl4040_read_avail(struct iio_dev *indio_dev,
default:
return -EINVAL;
}
+ case IIO_CHAN_INFO_CALIBBIAS:
+ switch (chan->type) {
+ case IIO_PROXIMITY:
+ *vals = (int *)vcnl4040_ps_calibbias_ua;
+ *length = 2 * ARRAY_SIZE(vcnl4040_ps_calibbias_ua);
+ *type = IIO_VAL_INT_PLUS_MICRO;
+ return IIO_AVAIL_LIST;
+ default:
+ return -EINVAL;
+ }
default:
return -EINVAL;
}
@@ -1729,9 +1819,11 @@ static const struct iio_chan_spec vcnl4040_channels[] = {
.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_OVERSAMPLING_RATIO),
+ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) |
+ BIT(IIO_CHAN_INFO_CALIBBIAS),
.info_mask_separate_available = BIT(IIO_CHAN_INFO_INT_TIME) |
- BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) |
+ BIT(IIO_CHAN_INFO_CALIBBIAS),
.ext_info = vcnl4000_ext_info,
.event_spec = vcnl4040_event_spec,
.num_event_specs = ARRAY_SIZE(vcnl4040_event_spec),
--
2.30.2