[PATCH 1/4] iio: proximity: vcnl3020: add periodic mode

Ivan Mikhaylov
2021-04-30T15:16:17Z

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

Signed-off-by: Ivan Mikhaylov <i.mikhaylov@yadro.com>
---
drivers/iio/proximity/vcnl3020.c | 138 +++++++++++++++++++++++++++++++
1 file changed, 138 insertions(+)

diff --git a/drivers/iio/proximity/vcnl3020.c b/drivers/iio/proximity/vcnl3020.c
index 43817f6b3086..25c6bdba3ede 100644
--- a/drivers/iio/proximity/vcnl3020.c
+++ b/drivers/iio/proximity/vcnl3020.c
@@ -36,6 +36,21 @@
#define VCNL_PS_OD BIT(3) /* start on-demand proximity
* measurement
*/
+#define VCNL_PS_EN BIT(1) /* Enables periodic proximity
+ * measurement
+ */
+#define VCNL_PS_SELFTIMED_EN BIT(0) /* Enables state machine and LP
+ * oscillator for self timed
+ * measurements
+ */
+
+/* Bit masks for ICR */
+#define VCNL_ICR_THRES_EN BIT(1) /* Enable interrupts on low or high
+ * thresholds */
+
+/* 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
@@ -215,12 +230,124 @@ static int vcnl3020_write_proxy_samp_freq(struct vcnl3020_data *data, int val,
return regmap_write(data->regmap, VCNL_PROXIMITY_RATE, index);
}

+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 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_config_threshold(struct iio_dev *indio_dev, bool state)
+{
+ struct vcnl3020_data *data = iio_priv(indio_dev);
+ int rc;
+ int icr;
+ int cmd;
+ int isr;
+
+ if (state) {
+ rc = iio_device_claim_direct_mode(indio_dev);
+ if (rc)
+ return rc;
+
+ /* Enable periodic measurement of proximity data. */
+ cmd = VCNL_PS_EN | VCNL_PS_SELFTIMED_EN;
+
+ /*
+ * Enable interrupts on threshold, for proximity data by
+ * default.
+ */
+ icr = VCNL_ICR_THRES_EN;
+ } else {
+ if (!vcnl3020_is_thr_enabled(data))
+ return 0;
+
+ cmd = 0;
+ icr = 0;
+ isr = 0;
+ }
+
+ rc = regmap_write(data->regmap, VCNL_COMMAND, cmd);
+ if (rc)
+ goto end;
+
+ rc = regmap_write(data->regmap, VCNL_PS_ICR, icr);
+ if (rc)
+ goto end;
+
+ if (!state)
+ /* Clear interrupts */
+ rc = regmap_write(data->regmap, VCNL_ISR, isr);
+
+end:
+ if (state)
+ iio_device_release_direct_mode(indio_dev);
+
+ return rc;
+}
+
+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_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),
},
};

@@ -233,6 +360,11 @@ static int vcnl3020_read_raw(struct iio_dev *indio_dev,

switch (mask) {
case IIO_CHAN_INFO_RAW:
+
+ /* Protect against event capture. */
+ if (vcnl3020_is_in_periodic_mode(data))
+ return -EBUSY;
+
rc = vcnl3020_measure_proximity(data, val);
if (rc)
return rc;
@@ -254,6 +386,10 @@ static int vcnl3020_write_raw(struct iio_dev *indio_dev,
int rc;
struct vcnl3020_data *data = iio_priv(indio_dev);

+ /* Protect against event capture. */
+ if (vcnl3020_is_in_periodic_mode(data))
+ return -EBUSY;
+
switch (mask) {
case IIO_CHAN_INFO_SAMP_FREQ:
rc = iio_device_claim_direct_mode(indio_dev);
@@ -287,6 +423,8 @@ static const struct iio_info vcnl3020_info = {
.read_raw = vcnl3020_read_raw,
.write_raw = vcnl3020_write_raw,
.read_avail = vcnl3020_read_avail,
+ .read_event_config = vcnl3020_read_event_config,
+ .write_event_config = vcnl3020_write_event_config,
};

static const struct regmap_config vcnl3020_regmap_config = {
--
2.26.3