[PATCH 7/9] iio: imu: st_lsm6dsx: make event management functions generic

[Francesco Lavra <flavra@baylibre.com>]

In preparation for adding support for more event types, use an
array indexed by event ID instead of a scalar value to store
enabled events, and refactor the functions to configure and report
events so that their implementation is not specific for wakeup
events. Move the logic to update the global event interrupt enable
flag from st_lsm6dsx_event_setup() to its calling function, so that
it can take into account also event sources different from the
source being configured. While changing the signature of the
st_lsm6dsx_event_setup() function, opportunistically add the
currently unused `axis` parameter, which will be used when adding
support for enabling and disabling events on a per axis basis.

Signed-off-by: Francesco Lavra <flavra@baylibre.com>
---
 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h      |   2 +-
 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c | 127 +++++++++++++------
 2 files changed, 88 insertions(+), 41 deletions(-)

diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
index 98aa3cfb711b..0e0642ca1b6f 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
@@ -421,7 +421,7 @@ struct st_lsm6dsx_hw {
 	u8 sip;
 
 	u8 irq_routing;
-	u8 enable_event;
+	u8 enable_event[ST_LSM6DSX_EVENT_MAX];
 
 	u8 *buff;
 
diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
index ea145e15cd36..87d40e70ca26 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
@@ -1673,11 +1673,16 @@ static int
 st_lsm6dsx_check_events(struct st_lsm6dsx_sensor *sensor)
 {
 	struct st_lsm6dsx_hw *hw = sensor->hw;
+	int event;
 
 	if (sensor->id != ST_LSM6DSX_ID_ACC)
 		return 0;
 
-	return hw->enable_event;
+	for (event = 0; event < ST_LSM6DSX_EVENT_MAX; event++) {
+		if (hw->enable_event[event])
+			return true;
+	}
+	return false;
 }
 
 int st_lsm6dsx_sensor_set_enable(struct st_lsm6dsx_sensor *sensor,
@@ -1790,9 +1795,10 @@ static int st_lsm6dsx_write_raw(struct iio_dev *iio_dev,
 	return err;
 }
 
-static int st_lsm6dsx_event_setup(struct st_lsm6dsx_hw *hw, bool state)
+static int st_lsm6dsx_event_setup(struct st_lsm6dsx_hw *hw, enum st_lsm6dsx_event_id event,
+				  int axis, bool state)
 {
-	const struct st_lsm6dsx_reg *reg;
+	const struct st_lsm6dsx_event_src *src = &hw->settings->event_settings.sources[event];
 	u8 enable_mask;
 	unsigned int data;
 	int err;
@@ -1800,22 +1806,23 @@ static int st_lsm6dsx_event_setup(struct st_lsm6dsx_hw *hw, bool state)
 	if (!hw->irq_routing)
 		return -ENOTSUPP;
 
-	reg = &hw->settings->event_settings.enable_reg;
-	if (reg->addr) {
-		data = ST_LSM6DSX_SHIFT_VAL(state, reg->mask);
-		err = st_lsm6dsx_update_bits_locked(hw, reg->addr,
-						    reg->mask, data);
-		if (err < 0)
-			return err;
-	}
-
-	/* Enable wakeup interrupt */
-	enable_mask = hw->settings->event_settings.sources[ST_LSM6DSX_EVENT_WAKEUP].enable_mask;
+	/* Enable/disable event interrupt */
+	enable_mask = src->enable_mask;
 	data = ST_LSM6DSX_SHIFT_VAL(state, enable_mask);
 	return st_lsm6dsx_update_bits_locked(hw, hw->irq_routing,
 					     enable_mask, data);
 }
 
+static enum st_lsm6dsx_event_id st_lsm6dsx_get_event_id(enum iio_event_type type)
+{
+	switch (type) {
+	case IIO_EV_TYPE_THRESH:
+		return ST_LSM6DSX_EVENT_WAKEUP;
+	default:
+		return ST_LSM6DSX_EVENT_MAX;
+	}
+}
+
 static int st_lsm6dsx_read_event(struct iio_dev *iio_dev,
 				 const struct iio_chan_spec *chan,
 				 enum iio_event_type type,
@@ -1825,14 +1832,15 @@ static int st_lsm6dsx_read_event(struct iio_dev *iio_dev,
 {
 	struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev);
 	struct st_lsm6dsx_hw *hw = sensor->hw;
+	enum st_lsm6dsx_event_id event = st_lsm6dsx_get_event_id(type);
 	const struct st_lsm6dsx_reg *reg;
 	u8 data;
 	int err;
 
-	if (type != IIO_EV_TYPE_THRESH)
+	if (event == ST_LSM6DSX_EVENT_MAX)
 		return -EINVAL;
 
-	reg = &hw->settings->event_settings.sources[ST_LSM6DSX_EVENT_WAKEUP].value;
+	reg = &hw->settings->event_settings.sources[event].value;
 	err = st_lsm6dsx_read_locked(hw, reg->addr, &data, sizeof(data));
 	if (err < 0)
 		return err;
@@ -1851,19 +1859,20 @@ st_lsm6dsx_write_event(struct iio_dev *iio_dev,
 		       enum iio_event_info info,
 		       int val, int val2)
 {
+	enum st_lsm6dsx_event_id event = st_lsm6dsx_get_event_id(type);
 	struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev);
 	struct st_lsm6dsx_hw *hw = sensor->hw;
 	const struct st_lsm6dsx_reg *reg;
 	unsigned int data;
 	int err;
 
-	if (type != IIO_EV_TYPE_THRESH)
+	if (event == ST_LSM6DSX_EVENT_MAX)
 		return -EINVAL;
 
 	if (val < 0 || val > 31)
 		return -EINVAL;
 
-	reg = &hw->settings->event_settings.sources[ST_LSM6DSX_EVENT_WAKEUP].value;
+	reg = &hw->settings->event_settings.sources[event].value;
 	data = ST_LSM6DSX_SHIFT_VAL(val, reg->mask);
 	err = st_lsm6dsx_update_bits_locked(hw, reg->addr,
 					    reg->mask, data);
@@ -1879,13 +1888,14 @@ st_lsm6dsx_read_event_config(struct iio_dev *iio_dev,
 			     enum iio_event_type type,
 			     enum iio_event_direction dir)
 {
+	enum st_lsm6dsx_event_id event = st_lsm6dsx_get_event_id(type);
 	struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev);
 	struct st_lsm6dsx_hw *hw = sensor->hw;
 
-	if (type != IIO_EV_TYPE_THRESH)
+	if (event == ST_LSM6DSX_EVENT_MAX)
 		return -EINVAL;
 
-	return !!(hw->enable_event & BIT(chan->channel2));
+	return !!(hw->enable_event[event] & BIT(chan->channel2));
 }
 
 static int
@@ -1894,22 +1904,25 @@ st_lsm6dsx_write_event_config(struct iio_dev *iio_dev,
 			      enum iio_event_type type,
 			      enum iio_event_direction dir, bool state)
 {
+	enum st_lsm6dsx_event_id event = st_lsm6dsx_get_event_id(type);
 	struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev);
 	struct st_lsm6dsx_hw *hw = sensor->hw;
+	int axis = chan->channel2;
 	u8 enable_event;
 	int err;
+	bool any_events_enabled = false;
 
-	if (type != IIO_EV_TYPE_THRESH)
+	if (event == ST_LSM6DSX_EVENT_MAX)
 		return -EINVAL;
 
 	if (state) {
-		enable_event = hw->enable_event | BIT(chan->channel2);
+		enable_event = hw->enable_event[event] | BIT(axis);
 
 		/* do not enable events if they are already enabled */
-		if (hw->enable_event)
+		if (hw->enable_event[event])
 			goto out;
 	} else {
-		enable_event = hw->enable_event & ~BIT(chan->channel2);
+		enable_event = hw->enable_event[event] & ~BIT(axis);
 
 		/* only turn off sensor if no events is enabled */
 		if (enable_event)
@@ -1917,22 +1930,43 @@ st_lsm6dsx_write_event_config(struct iio_dev *iio_dev,
 	}
 
 	/* stop here if no changes have been made */
-	if (hw->enable_event == enable_event)
+	if (hw->enable_event[event] == enable_event)
 		return 0;
 
-	err = st_lsm6dsx_event_setup(hw, state);
+	err = st_lsm6dsx_event_setup(hw, event, axis, state);
 	if (err < 0)
 		return err;
 
 	mutex_lock(&hw->conf_lock);
-	if (enable_event || !(hw->fifo_mask & BIT(sensor->id)))
+	if (!enable_event) {
+		enum st_lsm6dsx_event_id other_event;
+
+		for (other_event = 0; other_event < ST_LSM6DSX_EVENT_MAX; other_event++) {
+			if (other_event != event && hw->enable_event[other_event]) {
+				any_events_enabled = true;
+				break;
+			}
+		}
+	}
+	if (enable_event || !any_events_enabled) {
+		const struct st_lsm6dsx_reg *reg = &hw->settings->event_settings.enable_reg;
+
+		if (reg->addr) {
+			err = regmap_update_bits(hw->regmap, reg->addr, reg->mask,
+						 ST_LSM6DSX_SHIFT_VAL(state, reg->mask));
+			if (err < 0)
+				goto unlock_out;
+		}
+	}
+	if (enable_event || (!any_events_enabled && !(hw->fifo_mask & BIT(sensor->id))))
 		err = __st_lsm6dsx_sensor_set_enable(sensor, state);
+unlock_out:
 	mutex_unlock(&hw->conf_lock);
 	if (err < 0)
 		return err;
 
 out:
-	hw->enable_event = enable_event;
+	hw->enable_event[event] = enable_event;
 
 	return 0;
 }
@@ -2410,18 +2444,20 @@ static struct iio_dev *st_lsm6dsx_alloc_iiodev(struct st_lsm6dsx_hw *hw,
 }
 
 static bool
-st_lsm6dsx_report_motion_event(struct st_lsm6dsx_hw *hw)
+st_lsm6dsx_report_events(struct st_lsm6dsx_hw *hw, enum st_lsm6dsx_event_id id,
+			 enum iio_event_type type, enum iio_event_direction dir)
 {
+	u8 enable_event = hw->enable_event[id];
 	const struct st_lsm6dsx_event_settings *event_settings;
 	const struct st_lsm6dsx_event_src *event_src;
 	int err, data;
 	s64 timestamp;
 
-	if (!hw->enable_event)
+	if (!enable_event)
 		return false;
 
 	event_settings = &hw->settings->event_settings;
-	event_src = &event_settings->sources[ST_LSM6DSX_EVENT_WAKEUP];
+	event_src = &event_settings->sources[id];
 	err = st_lsm6dsx_read_locked(hw, event_src->status_reg,
 				     &data, sizeof(data));
 	if (err < 0)
@@ -2429,38 +2465,49 @@ st_lsm6dsx_report_motion_event(struct st_lsm6dsx_hw *hw)
 
 	timestamp = iio_get_time_ns(hw->iio_devs[ST_LSM6DSX_ID_ACC]);
 	if ((data & event_src->status_z_mask) &&
-	    (hw->enable_event & BIT(IIO_MOD_Z)))
+	    (enable_event & BIT(IIO_MOD_Z)))
 		iio_push_event(hw->iio_devs[ST_LSM6DSX_ID_ACC],
 			       IIO_MOD_EVENT_CODE(IIO_ACCEL,
 						  0,
 						  IIO_MOD_Z,
-						  IIO_EV_TYPE_THRESH,
-						  IIO_EV_DIR_EITHER),
+						  type,
+						  dir),
 						  timestamp);
 
 	if ((data & event_src->status_y_mask) &&
-	    (hw->enable_event & BIT(IIO_MOD_Y)))
+	    (enable_event & BIT(IIO_MOD_Y)))
 		iio_push_event(hw->iio_devs[ST_LSM6DSX_ID_ACC],
 			       IIO_MOD_EVENT_CODE(IIO_ACCEL,
 						  0,
 						  IIO_MOD_Y,
-						  IIO_EV_TYPE_THRESH,
-						  IIO_EV_DIR_EITHER),
+						  type,
+						  dir),
 						  timestamp);
 
 	if ((data & event_src->status_x_mask) &&
-	    (hw->enable_event & BIT(IIO_MOD_X)))
+	    (enable_event & BIT(IIO_MOD_X)))
 		iio_push_event(hw->iio_devs[ST_LSM6DSX_ID_ACC],
 			       IIO_MOD_EVENT_CODE(IIO_ACCEL,
 						  0,
 						  IIO_MOD_X,
-						  IIO_EV_TYPE_THRESH,
-						  IIO_EV_DIR_EITHER),
+						  type,
+						  dir),
 						  timestamp);
 
 	return data & event_src->status_mask;
 }
 
+static bool
+st_lsm6dsx_report_motion_event(struct st_lsm6dsx_hw *hw)
+{
+	bool events_found;
+
+	events_found = st_lsm6dsx_report_events(hw, ST_LSM6DSX_EVENT_WAKEUP, IIO_EV_TYPE_THRESH,
+						IIO_EV_DIR_EITHER);
+
+	return events_found;
+}
+
 static irqreturn_t st_lsm6dsx_handler_thread(int irq, void *private)
 {
 	struct st_lsm6dsx_hw *hw = private;
-- 
2.39.5