iio: imu: st_lsm6dsx: add read_fifo callback to fifo_ops

Remove static qualifier from st_lsm6dsx_read_fifo definition and
introduce read_fifo function pointer in fifo_ops data structure
in order to run the proper read_fifo routine since other compliant
devices will use a different FIFO queueing scheme.
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h

@@ -41,13 +41,17 @@ struct st_lsm6dsx_reg {
 	u8 mask;
 };
 
+struct st_lsm6dsx_hw;
+
 /**
  * struct st_lsm6dsx_fifo_ops - ST IMU FIFO settings
+ * @read_fifo: Read FIFO callback.
  * @fifo_th: FIFO threshold register info (addr + mask).
  * @fifo_diff: FIFO diff status register info (addr + mask).
  * @th_wl: FIFO threshold word length.
  */
 struct st_lsm6dsx_fifo_ops {
+	int (*read_fifo)(struct st_lsm6dsx_hw *hw);
 	struct {
 		u8 addr;
 		u16 mask;
@@ -175,5 +179,6 @@ int st_lsm6dsx_update_watermark(struct st_lsm6dsx_sensor *sensor,
 int st_lsm6dsx_flush_fifo(struct st_lsm6dsx_hw *hw);
 int st_lsm6dsx_set_fifo_mode(struct st_lsm6dsx_hw *hw,
 			     enum st_lsm6dsx_fifo_mode fifo_mode);
+int st_lsm6dsx_read_fifo(struct st_lsm6dsx_hw *hw);
 
 #endif /* ST_LSM6DSX_H */

drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c

@@ -283,7 +283,7 @@ static inline int st_lsm6dsx_read_block(struct st_lsm6dsx_hw *hw, u8 *data,
  *
  * Return: Number of bytes read from the FIFO
  */
-static int st_lsm6dsx_read_fifo(struct st_lsm6dsx_hw *hw)
+int st_lsm6dsx_read_fifo(struct st_lsm6dsx_hw *hw)
 {
 	u16 fifo_len, pattern_len = hw->sip * ST_LSM6DSX_SAMPLE_SIZE;
 	u16 fifo_diff_mask = hw->settings->fifo_ops.fifo_diff.mask;
@@ -407,7 +407,7 @@ int st_lsm6dsx_flush_fifo(struct st_lsm6dsx_hw *hw)
 
 	mutex_lock(&hw->fifo_lock);
 
-	st_lsm6dsx_read_fifo(hw);
+	hw->settings->fifo_ops.read_fifo(hw);
 	err = st_lsm6dsx_set_fifo_mode(hw, ST_LSM6DSX_FIFO_BYPASS);
 
 	mutex_unlock(&hw->fifo_lock);
@@ -479,7 +479,7 @@ static irqreturn_t st_lsm6dsx_handler_thread(int irq, void *private)
 	int count;
 
 	mutex_lock(&hw->fifo_lock);
-	count = st_lsm6dsx_read_fifo(hw);
+	count = hw->settings->fifo_ops.read_fifo(hw);
 	mutex_unlock(&hw->fifo_lock);
 
 	return !count ? IRQ_NONE : IRQ_HANDLED;

drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c

@@ -171,6 +171,7 @@ static const struct st_lsm6dsx_settings st_lsm6dsx_sensor_settings[] = {
 			},
 		},
 		.fifo_ops = {
+			.read_fifo = st_lsm6dsx_read_fifo,
 			.fifo_th = {
 				.addr = 0x06,
 				.mask = GENMASK(11, 0),
@@ -217,6 +218,7 @@ static const struct st_lsm6dsx_settings st_lsm6dsx_sensor_settings[] = {
 			},
 		},
 		.fifo_ops = {
+			.read_fifo = st_lsm6dsx_read_fifo,
 			.fifo_th = {
 				.addr = 0x06,
 				.mask = GENMASK(11, 0),
@@ -265,6 +267,7 @@ static const struct st_lsm6dsx_settings st_lsm6dsx_sensor_settings[] = {
 			},
 		},
 		.fifo_ops = {
+			.read_fifo = st_lsm6dsx_read_fifo,
 			.fifo_th = {
 				.addr = 0x06,
 				.mask = GENMASK(10, 0),