iio: accel: bma400: Ensure VDDIO is enable defore reading the chip ID.

The regulator enables were after the check on the chip variant, which was
very unlikely to return a correct value when not powered.
Presumably all the device anyone is testing on have a regulator that
is already powered up when this code runs for reasons beyond the scope
of this driver. Move the read call down a few lines.

Fixes: 3cf7ded15e40 ("iio: accel: bma400: basic regulator support")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dan Robertson <dan@dlrobertson.com>
Cc: <Stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20221002144133.3771029-1-jic23@kernel.org

diff --git a/drivers/iio/accel/bma400_core.c b/drivers/iio/accel/bma400_core.c
index ad8fce3..490c342 100644 (file)
--- a/drivers/iio/accel/bma400_core.c
+++ b/drivers/iio/accel/bma400_core.c
@@ -869,18 +869,6 @@ static int bma400_init(struct bma400_data *data)
        unsigned int val;
        int ret;
 
-       /* Try to read chip_id register. It must return 0x90. */
-       ret = regmap_read(data->regmap, BMA400_CHIP_ID_REG, &val);
-       if (ret) {
-               dev_err(data->dev, "Failed to read chip id register\n");
-               return ret;
-       }
-
-       if (val != BMA400_ID_REG_VAL) {
-               dev_err(data->dev, "Chip ID mismatch\n");
-               return -ENODEV;
-       }
-
        data->regulators[BMA400_VDD_REGULATOR].supply = "vdd";
        data->regulators[BMA400_VDDIO_REGULATOR].supply = "vddio";
        ret = devm_regulator_bulk_get(data->dev,
@@ -906,6 +894,18 @@ static int bma400_init(struct bma400_data *data)
        if (ret)
                return ret;
 
+       /* Try to read chip_id register. It must return 0x90. */
+       ret = regmap_read(data->regmap, BMA400_CHIP_ID_REG, &val);
+       if (ret) {
+               dev_err(data->dev, "Failed to read chip id register\n");
+               return ret;
+       }
+
+       if (val != BMA400_ID_REG_VAL) {
+               dev_err(data->dev, "Chip ID mismatch\n");
+               return -ENODEV;
+       }
+
        ret = bma400_get_power_mode(data);
        if (ret) {
                dev_err(data->dev, "Failed to get the initial power-mode\n");