[PATCH v5 07/10] iio: accel: bma400: Add activity recognition support

From: Jagath Jog J
Date: Thu May 05 2022 - 09:31:18 EST


Add support for activity recognition like STILL, WALKING, RUNNING
and these events are pushed to the userspace whenever the STEP
interrupt occurs.

Signed-off-by: Jagath Jog J <jagathjog1996@xxxxxxxxx>
---
drivers/iio/accel/bma400_core.c | 85 +++++++++++++++++++++++++++++++++
1 file changed, 85 insertions(+)

diff --git a/drivers/iio/accel/bma400_core.c b/drivers/iio/accel/bma400_core.c
index 50932fc1c854..1e4923064b63 100644
--- a/drivers/iio/accel/bma400_core.c
+++ b/drivers/iio/accel/bma400_core.c
@@ -67,6 +67,12 @@ struct bma400_sample_freq {
int uhz;
};

+enum bma400_activity {
+ BMA400_STILL,
+ BMA400_WALKING,
+ BMA400_RUNNING,
+};
+
struct bma400_data {
struct device *dev;
struct regmap *regmap;
@@ -80,6 +86,7 @@ struct bma400_data {
struct iio_trigger *trig;
int steps_enabled;
bool step_event_en;
+ bool activity_event_en;
/* Correct time stamp alignment */
struct {
__le16 buff[3];
@@ -184,6 +191,12 @@ static const struct iio_event_spec bma400_step_detect_event = {
.mask_separate = BIT(IIO_EV_INFO_ENABLE),
};

+static const struct iio_event_spec bma400_activity_event = {
+ .type = IIO_EV_TYPE_CHANGE,
+ .dir = IIO_EV_DIR_NONE,
+ .mask_shared_by_type = BIT(IIO_EV_INFO_ENABLE),
+};
+
#define BMA400_ACC_CHANNEL(_index, _axis) { \
.type = IIO_ACCEL, \
.modified = 1, \
@@ -205,6 +218,16 @@ static const struct iio_event_spec bma400_step_detect_event = {
}, \
}

+#define BMA400_ACTIVITY_CHANNEL(_chan2) { \
+ .type = IIO_ACTIVITY, \
+ .modified = 1, \
+ .channel2 = _chan2, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \
+ .scan_index = -1, /* No buffer support */ \
+ .event_spec = &bma400_activity_event, \
+ .num_event_specs = 1, \
+}
+
static const struct iio_chan_spec bma400_channels[] = {
BMA400_ACC_CHANNEL(0, X),
BMA400_ACC_CHANNEL(1, Y),
@@ -229,6 +252,9 @@ static const struct iio_chan_spec bma400_channels[] = {
.event_spec = &bma400_step_detect_event,
.num_event_specs = 1,
},
+ BMA400_ACTIVITY_CHANNEL(IIO_MOD_STILL),
+ BMA400_ACTIVITY_CHANNEL(IIO_MOD_WALKING),
+ BMA400_ACTIVITY_CHANNEL(IIO_MOD_RUNNING),
IIO_CHAN_SOFT_TIMESTAMP(4),
};

@@ -669,6 +695,20 @@ static void bma400_power_disable(void *data_ptr)
ERR_PTR(ret));
}

+static enum iio_modifier bma400_act_to_mod(enum bma400_activity activity)
+{
+ switch (activity) {
+ case BMA400_STILL:
+ return IIO_MOD_STILL;
+ case BMA400_WALKING:
+ return IIO_MOD_WALKING;
+ case BMA400_RUNNING:
+ return IIO_MOD_RUNNING;
+ default:
+ return IIO_NO_MOD;
+ }
+}
+
static int bma400_init(struct bma400_data *data)
{
unsigned int val;
@@ -766,6 +806,7 @@ static int bma400_read_raw(struct iio_dev *indio_dev,
int *val2, long mask)
{
struct bma400_data *data = iio_priv(indio_dev);
+ unsigned int activity;
int ret;

switch (mask) {
@@ -778,6 +819,21 @@ static int bma400_read_raw(struct iio_dev *indio_dev,
return ret;
case IIO_STEPS:
return bma400_get_steps_reg(data, val);
+ case IIO_ACTIVITY:
+ ret = regmap_read(data->regmap, BMA400_STEP_STAT_REG,
+ &activity);
+ if (ret)
+ return ret;
+ /*
+ * The device does not support confidence value levels,
+ * so we will always have 100% for current activity and
+ * 0% for the others.
+ */
+ if (chan->channel2 == bma400_act_to_mod(activity))
+ *val = 100;
+ else
+ *val = 0;
+ return IIO_VAL_INT;
default:
return -EINVAL;
}
@@ -927,6 +983,8 @@ static int bma400_read_event_config(struct iio_dev *indio_dev,
switch (chan->type) {
case IIO_STEPS:
return data->step_event_en;
+ case IIO_ACTIVITY:
+ return data->activity_event_en;
default:
return -EINVAL;
}
@@ -964,6 +1022,18 @@ static int bma400_write_event_config(struct iio_dev *indio_dev,
ret = bma400_steps_event_enable(data, state);
mutex_unlock(&data->mutex);
return ret;
+ case IIO_ACTIVITY:
+ mutex_lock(&data->mutex);
+ if (!data->step_event_en) {
+ ret = bma400_steps_event_enable(data, true);
+ if (ret) {
+ mutex_unlock(&data->mutex);
+ return ret;
+ }
+ }
+ data->activity_event_en = state;
+ mutex_unlock(&data->mutex);
+ return 0;
default:
return -EINVAL;
}
@@ -1049,6 +1119,7 @@ static irqreturn_t bma400_interrupt(int irq, void *private)
struct iio_dev *indio_dev = private;
struct bma400_data *data = iio_priv(indio_dev);
s64 timestamp = iio_get_time_ns(indio_dev);
+ unsigned int act;
int ret;

/* Lock to protect the data->status */
@@ -1069,6 +1140,20 @@ static irqreturn_t bma400_interrupt(int irq, void *private)
IIO_EV_TYPE_CHANGE,
IIO_EV_DIR_NONE),
timestamp);
+
+ if (data->activity_event_en) {
+ ret = regmap_read(data->regmap, BMA400_STEP_STAT_REG,
+ &act);
+ if (ret)
+ goto unlock_err;
+
+ iio_push_event(indio_dev,
+ IIO_MOD_EVENT_CODE(IIO_ACTIVITY, 0,
+ bma400_act_to_mod(act),
+ IIO_EV_TYPE_CHANGE,
+ IIO_EV_DIR_NONE),
+ timestamp);
+ }
}

if (FIELD_GET(BMA400_INT_DRDY_MSK, le16_to_cpu(data->status))) {
--
2.17.1