[PATCH v2 1/2] iio: proximity: vcnl3020: add periodic mode

From: Ivan Mikhaylov
Date: Mon Jun 21 2021 - 10:21:43 EST

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

Signed-off-by: Ivan Mikhaylov <i.mikhaylov@xxxxxxxxx>
---
drivers/iio/proximity/vcnl3020.c | 211 ++++++++++++++++++++++++++++++-
1 file changed, 209 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/proximity/vcnl3020.c b/drivers/iio/proximity/vcnl3020.c
index 43817f6b3086..2e65127d5359 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 +10,11 @@
#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/iio.h>
+#include <linux/iio/events.h>

#define VCNL3020_PROD_ID 0x21

@@ -37,6 +38,21 @@
* 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

@@ -215,12 +231,145 @@ 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_enable_periodic(struct iio_dev *indio_dev,
+ struct vcnl3020_data *data)
+{
+ int rc;
+ int icr;
+ int cmd;
+
+ mutex_lock(&data->lock);
+
+ /* 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;
+
+ rc = regmap_write(data->regmap, VCNL_COMMAND, cmd);
+ if (rc)
+ goto out_mutex;
+
+ rc = regmap_write(data->regmap, VCNL_PS_ICR, icr);
+
+out_mutex:
+ 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 out_mutex;
+
+ rc = regmap_write(data->regmap, VCNL_PS_ICR, 0);
+ if (rc)
+ goto out_mutex;
+
+ /* Clear interrupt flag bit */
+ rc = regmap_write(data->regmap, VCNL_ISR, 0);
+
+out_mutex:
+ 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);
+ int rc;
+
+ if (state) {
+ rc = vcnl3020_enable_periodic(indio_dev, data);
+ } else {
+ if (!vcnl3020_is_thr_enabled(data))
+ return 0;
+ rc = vcnl3020_disable_periodic(indio_dev, data);
+ }
+
+ 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 +382,11 @@ 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 +408,10 @@ 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 +445,8 @@ 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 = {
@@ -295,6 +455,38 @@ static const struct regmap_config vcnl3020_regmap_config = {
.max_register = VCNL_PS_MOD_ADJ,
};

+static irqreturn_t vcnl3020_handle_irq(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);
+ }
+
+ return IRQ_HANDLED;
+}
+
static int vcnl3020_probe(struct i2c_client *client)
{
struct vcnl3020_data *data;
@@ -327,6 +519,21 @@ static int vcnl3020_probe(struct i2c_client *client)
indio_dev->name = "vcnl3020";
indio_dev->modes = INDIO_DIRECT_MODE;

+ if (client->irq) {
+ rc = devm_request_irq(&client->dev, client->irq,
+ vcnl3020_handle_irq,
+ IRQF_TRIGGER_FALLING | 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;
+ }
+ } else {
+ dev_info(&client->dev, "Starting without irq handle\n");
+ }
+
return devm_iio_device_register(&client->dev, indio_dev);
}

--
2.31.1