[PATCH v4 9/9] iio: imu: st_lsm6dsx: add tap event detection

[Francesco Lavra <flavra@baylibre.com>]

In order to allow sensors to advertise tap event capability and report tap
events, define a new struct iio_event_spec array that includes a tap event
spec, and a new struct iio_chan_spec array that references the new
iio_event_spec array; for the LSM6DSV chip family, use the new
iio_chan_spec array and define an event source for tap events.
Tested on LSMDSV16X.

Signed-off-by: Francesco Lavra <flavra@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Acked-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h      |  1 +
 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c | 57 +++++++++++++++++++-
 2 files changed, 56 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
index 3edff8456a8f..957dae73e13d 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
@@ -245,6 +245,7 @@ struct st_lsm6dsx_shub_settings {
 
 enum st_lsm6dsx_event_id {
 	ST_LSM6DSX_EVENT_WAKEUP,
+	ST_LSM6DSX_EVENT_TAP,
 	ST_LSM6DSX_EVENT_MAX
 };
 
diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
index 04a3c65d4546..e99556ccacd4 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
@@ -105,6 +105,21 @@ static const struct iio_event_spec st_lsm6dsx_ev_motion[] = {
 	},
 };
 
+static const struct iio_event_spec st_lsm6dsx_ev_motion_tap[] = {
+	{
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_EITHER,
+		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
+				 BIT(IIO_EV_INFO_ENABLE),
+	},
+	{
+		.type = IIO_EV_TYPE_GESTURE,
+		.dir = IIO_EV_DIR_SINGLETAP,
+		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
+				 BIT(IIO_EV_INFO_ENABLE),
+	},
+};
+
 static const struct iio_chan_spec st_lsm6dsx_acc_channels[] = {
 	ST_LSM6DSX_CHANNEL_ACC(0x28, IIO_MOD_X, 0, st_lsm6dsx_ev_motion),
 	ST_LSM6DSX_CHANNEL_ACC(0x2a, IIO_MOD_Y, 1, st_lsm6dsx_ev_motion),
@@ -119,6 +134,13 @@ static const struct iio_chan_spec st_lsm6ds0_acc_channels[] = {
 	IIO_CHAN_SOFT_TIMESTAMP(3),
 };
 
+static const struct iio_chan_spec st_lsm6dsx_acc_tap_channels[] = {
+	ST_LSM6DSX_CHANNEL_ACC(0x28, IIO_MOD_X, 0, st_lsm6dsx_ev_motion_tap),
+	ST_LSM6DSX_CHANNEL_ACC(0x2a, IIO_MOD_Y, 1, st_lsm6dsx_ev_motion_tap),
+	ST_LSM6DSX_CHANNEL_ACC(0x2c, IIO_MOD_Z, 2, st_lsm6dsx_ev_motion_tap),
+	IIO_CHAN_SOFT_TIMESTAMP(3),
+};
+
 static const struct iio_chan_spec st_lsm6dsx_gyro_channels[] = {
 	ST_LSM6DSX_CHANNEL(IIO_ANGL_VEL, 0x22, IIO_MOD_X, 0),
 	ST_LSM6DSX_CHANNEL(IIO_ANGL_VEL, 0x24, IIO_MOD_Y, 1),
@@ -1260,8 +1282,8 @@ static const struct st_lsm6dsx_settings st_lsm6dsx_sensor_settings[] = {
 		},
 		.channels = {
 			[ST_LSM6DSX_ID_ACC] = {
-				.chan = st_lsm6dsx_acc_channels,
-				.len = ARRAY_SIZE(st_lsm6dsx_acc_channels),
+				.chan = st_lsm6dsx_acc_tap_channels,
+				.len = ARRAY_SIZE(st_lsm6dsx_acc_tap_channels),
 			},
 			[ST_LSM6DSX_ID_GYRO] = {
 				.chan = st_lsm6dsx_gyro_channels,
@@ -1438,6 +1460,32 @@ static const struct st_lsm6dsx_settings st_lsm6dsx_sensor_settings[] = {
 					.status_y_mask = BIT(1),
 					.status_x_mask = BIT(2),
 				},
+				[ST_LSM6DSX_EVENT_TAP] = {
+					.x_value = {
+						.addr = 0x57,
+						.mask = GENMASK(4, 0),
+					},
+					.y_value = {
+						.addr = 0x58,
+						.mask = GENMASK(4, 0),
+					},
+					.z_value = {
+						.addr = 0x59,
+						.mask = GENMASK(4, 0),
+					},
+					.enable_mask = BIT(6),
+					.enable_axis_reg = 0x56,
+					.enable_x_mask = BIT(3),
+					.enable_y_mask = BIT(2),
+					.enable_z_mask = BIT(1),
+					.status = {
+						.addr = 0x46,
+						.mask = BIT(5),
+					},
+					.status_x_mask = BIT(2),
+					.status_y_mask = BIT(1),
+					.status_z_mask = BIT(0),
+				},
 			},
 		},
 	},
@@ -1952,6 +2000,8 @@ st_lsm6dsx_get_event_id(enum iio_event_type type)
 	switch (type) {
 	case IIO_EV_TYPE_THRESH:
 		return ST_LSM6DSX_EVENT_WAKEUP;
+	case IIO_EV_TYPE_GESTURE:
+		return ST_LSM6DSX_EVENT_TAP;
 	default:
 		return ST_LSM6DSX_EVENT_MAX;
 	}
@@ -2620,6 +2670,9 @@ static bool st_lsm6dsx_report_motion_event(struct st_lsm6dsx_hw *hw)
 	events_found = st_lsm6dsx_report_events(hw, ST_LSM6DSX_EVENT_WAKEUP,
 						IIO_EV_TYPE_THRESH,
 						IIO_EV_DIR_EITHER);
+	events_found |= st_lsm6dsx_report_events(hw, ST_LSM6DSX_EVENT_TAP,
+						 IIO_EV_TYPE_GESTURE,
+						 IIO_EV_DIR_SINGLETAP);
 
 	return events_found;
 }
-- 
2.39.5