iio: imu: st_lsm6dsx: check if master_enable is located in primary page

Check if the master enable register is located in the primary or in the
secondary memory page. This is a preliminary patch to support i2c master
controller on lsm6dsm devices
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h

@@ -184,7 +184,11 @@ struct st_lsm6dsx_hw_ts_settings {
  */
 struct st_lsm6dsx_shub_settings {
 	struct st_lsm6dsx_reg page_mux;
-	struct st_lsm6dsx_reg master_en;
+	struct {
+		bool sec_page;
+		u8 addr;
+		u8 mask;
+	} master_en;
 	struct st_lsm6dsx_reg pullup_en;
 	struct st_lsm6dsx_reg aux_sens;
 	struct st_lsm6dsx_reg wr_once;

drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c

@@ -868,6 +868,7 @@ static const struct st_lsm6dsx_settings st_lsm6dsx_sensor_settings[] = {
 				.mask = BIT(6),
 			},
 			.master_en = {
+				.sec_page = true,
 				.addr = 0x14,
 				.mask = BIT(2),
 			},
@@ -1243,6 +1244,7 @@ static const struct st_lsm6dsx_settings st_lsm6dsx_sensor_settings[] = {
 				.mask = BIT(6),
 			},
 			.master_en = {
+				.sec_page = true,
 				.addr = 0x14,
 				.mask = BIT(2),
 			},

drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_shub.c

@@ -185,15 +185,18 @@ static int st_lsm6dsx_shub_master_enable(struct st_lsm6dsx_sensor *sensor,
 	mutex_lock(&hw->page_lock);
 
 	hub_settings = &hw->settings->shub_settings;
-	err = st_lsm6dsx_set_page(hw, true);
-	if (err < 0)
-		goto out;
+	if (hub_settings->master_en.sec_page) {
+		err = st_lsm6dsx_set_page(hw, true);
+		if (err < 0)
+			goto out;
+	}
 
 	data = ST_LSM6DSX_SHIFT_VAL(enable, hub_settings->master_en.mask);
 	err = regmap_update_bits(hw->regmap, hub_settings->master_en.addr,
 				 hub_settings->master_en.mask, data);
 
-	st_lsm6dsx_set_page(hw, false);
+	if (hub_settings->master_en.sec_page)
+		st_lsm6dsx_set_page(hw, false);
 out:
 	mutex_unlock(&hw->page_lock);