[PATCH 5.19 022/717] iio: pressure: dps310: Refactor startup procedure

Greg Kroah-Hartman
2022-10-22T07:36:04Z

From: Eddie James <eajames@linux.ibm.com>

commit c2329717bdd3fa62f8a2f3d8d85ad0bee4556bd7 upstream.

Move the startup procedure into a function, and correct a missing
check on the return code for writing the PRS_CFG register.

Cc: <stable@vger.kernel.org>
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220915195719.136812-2-eajames@linux.ibm.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/iio/pressure/dps310.c | 188 ++++++++++++++++++++++--------------------
1 file changed, 99 insertions(+), 89 deletions(-)

--- a/drivers/iio/pressure/dps310.c
+++ b/drivers/iio/pressure/dps310.c
@@ -159,6 +159,102 @@ static int dps310_get_coefs(struct dps31
return 0;
}

+/*
+ * Some versions of the chip will read temperatures in the ~60C range when
+ * it's actually ~20C. This is the manufacturer recommended workaround
+ * to correct the issue. The registers used below are undocumented.
+ */
+static int dps310_temp_workaround(struct dps310_data *data)
+{
+ int rc;
+ int reg;
+
+ rc = regmap_read(data->regmap, 0x32, &reg);
+ if (rc)
+ return rc;
+
+ /*
+ * If bit 1 is set then the device is okay, and the workaround does not
+ * need to be applied
+ */
+ if (reg & BIT(1))
+ return 0;
+
+ rc = regmap_write(data->regmap, 0x0e, 0xA5);
+ if (rc)
+ return rc;
+
+ rc = regmap_write(data->regmap, 0x0f, 0x96);
+ if (rc)
+ return rc;
+
+ rc = regmap_write(data->regmap, 0x62, 0x02);
+ if (rc)
+ return rc;
+
+ rc = regmap_write(data->regmap, 0x0e, 0x00);
+ if (rc)
+ return rc;
+
+ return regmap_write(data->regmap, 0x0f, 0x00);
+}
+
+static int dps310_startup(struct dps310_data *data)
+{
+ int rc;
+ int ready;
+
+ /*
+ * Set up pressure sensor in single sample, one measurement per second
+ * mode
+ */
+ rc = regmap_write(data->regmap, DPS310_PRS_CFG, 0);
+ if (rc)
+ return rc;
+
+ /*
+ * Set up external (MEMS) temperature sensor in single sample, one
+ * measurement per second mode
+ */
+ rc = regmap_write(data->regmap, DPS310_TMP_CFG, DPS310_TMP_EXT);
+ if (rc)
+ return rc;
+
+ /* Temp and pressure shifts are disabled when PRC <= 8 */
+ rc = regmap_write_bits(data->regmap, DPS310_CFG_REG,
+ DPS310_PRS_SHIFT_EN | DPS310_TMP_SHIFT_EN, 0);
+ if (rc)
+ return rc;
+
+ /* MEAS_CFG doesn't update correctly unless first written with 0 */
+ rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG,
+ DPS310_MEAS_CTRL_BITS, 0);
+ if (rc)
+ return rc;
+
+ /* Turn on temperature and pressure measurement in the background */
+ rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG,
+ DPS310_MEAS_CTRL_BITS, DPS310_PRS_EN |
+ DPS310_TEMP_EN | DPS310_BACKGROUND);
+ if (rc)
+ return rc;
+
+ /*
+ * Calibration coefficients required for reporting temperature.
+ * They are available 40ms after the device has started
+ */
+ rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready,
+ ready & DPS310_COEF_RDY, 10000, 40000);
+ if (rc)
+ return rc;
+
+ rc = dps310_get_coefs(data);
+ if (rc)
+ return rc;
+
+ return dps310_temp_workaround(data);
+}
+
static int dps310_get_pres_precision(struct dps310_data *data)
{
int rc;
@@ -677,52 +773,12 @@ static const struct iio_info dps310_info
.write_raw = dps310_write_raw,
};

-/*
- * Some verions of chip will read temperatures in the ~60C range when
- * its actually ~20C. This is the manufacturer recommended workaround
- * to correct the issue. The registers used below are undocumented.
- */
-static int dps310_temp_workaround(struct dps310_data *data)
-{
- int rc;
- int reg;
-
- rc = regmap_read(data->regmap, 0x32, &reg);
- if (rc < 0)
- return rc;
-
- /*
- * If bit 1 is set then the device is okay, and the workaround does not
- * need to be applied
- */
- if (reg & BIT(1))
- return 0;
-
- rc = regmap_write(data->regmap, 0x0e, 0xA5);
- if (rc < 0)
- return rc;
-
- rc = regmap_write(data->regmap, 0x0f, 0x96);
- if (rc < 0)
- return rc;
-
- rc = regmap_write(data->regmap, 0x62, 0x02);
- if (rc < 0)
- return rc;
-
- rc = regmap_write(data->regmap, 0x0e, 0x00);
- if (rc < 0)
- return rc;
-
- return regmap_write(data->regmap, 0x0f, 0x00);
-}
-
static int dps310_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct dps310_data *data;
struct iio_dev *iio;
- int rc, ready;
+ int rc;

iio = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (!iio)
@@ -747,54 +803,8 @@ static int dps310_probe(struct i2c_clien
if (rc)
return rc;

- /*
- * Set up pressure sensor in single sample, one measurement per second
- * mode
- */
- rc = regmap_write(data->regmap, DPS310_PRS_CFG, 0);
-
- /*
- * Set up external (MEMS) temperature sensor in single sample, one
- * measurement per second mode
- */
- rc = regmap_write(data->regmap, DPS310_TMP_CFG, DPS310_TMP_EXT);
- if (rc < 0)
- return rc;
-
- /* Temp and pressure shifts are disabled when PRC <= 8 */
- rc = regmap_write_bits(data->regmap, DPS310_CFG_REG,
- DPS310_PRS_SHIFT_EN | DPS310_TMP_SHIFT_EN, 0);
- if (rc < 0)
- return rc;
-
- /* MEAS_CFG doesn't update correctly unless first written with 0 */
- rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG,
- DPS310_MEAS_CTRL_BITS, 0);
- if (rc < 0)
- return rc;
-
- /* Turn on temperature and pressure measurement in the background */
- rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG,
- DPS310_MEAS_CTRL_BITS, DPS310_PRS_EN |
- DPS310_TEMP_EN | DPS310_BACKGROUND);
- if (rc < 0)
- return rc;
-
- /*
- * Calibration coefficients required for reporting temperature.
- * They are available 40ms after the device has started
- */
- rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready,
- ready & DPS310_COEF_RDY, 10000, 40000);
- if (rc < 0)
- return rc;
-
- rc = dps310_get_coefs(data);
- if (rc < 0)
- return rc;
-
- rc = dps310_temp_workaround(data);
- if (rc < 0)
+ rc = dps310_startup(data);
+ if (rc)
return rc;

rc = devm_iio_device_register(&client->dev, iio);