From: Christopher Bostic <cbos...@linux.vnet.ibm.com>
Add a manufacturer's suggested workaround to deal with early revisions
of chip that don't indicate correct temperature. Readings can be in the
~60C range when they should be in the ~20's.
Signed-off-by: Christopher Bostic <cbos...@linux.vnet.ibm.com>
Signed-off-by: Joel Stanley <j...@jms.id.au>
Signed-off-by: Eddie James <eaja...@linux.ibm.com>
---
drivers/iio/pressure/dps310.c | 51 ++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 50 insertions(+), 1 deletion(-)
diff --git a/drivers/iio/pressure/dps310.c b/drivers/iio/pressure/dps310.c
index 7afaa88..c42808e 100644
--- a/drivers/iio/pressure/dps310.c
+++ b/drivers/iio/pressure/dps310.c
@@ -221,6 +221,9 @@ static bool dps310_is_writeable_reg(struct device *dev,
unsigned int reg)
case DPS310_MEAS_CFG:
case DPS310_CFG_REG:
case DPS310_RESET:
+ case 0x0e:
+ case 0x0f:
+ case 0x62:
return true;
default:
return false;
@@ -237,6 +240,7 @@ static bool dps310_is_volatile_reg(struct device *dev,
unsigned int reg)
case DPS310_TMP_B1:
case DPS310_TMP_B2:
case DPS310_MEAS_CFG:
+ case 0x32:
return true;
default:
return false;
@@ -314,7 +318,7 @@ static int dps310_read_raw(struct iio_dev *iio,
.writeable_reg = dps310_is_writeable_reg,
.volatile_reg = dps310_is_volatile_reg,
.cache_type = REGCACHE_RBTREE,
- .max_register = 0x29,
+ .max_register = 0x62,
};
static const struct iio_info dps310_info = {
@@ -322,6 +326,47 @@ static int dps310_read_raw(struct iio_dev *iio,
.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.
+ */
+static int dps310_temp_workaround(struct dps310_data *data)
+{
+ int r, reg;
+
+ r = regmap_read(data->regmap, 0x32, ®);
+ if (r < 0)
+ return r;
+
+ /*
+ * 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;
+
+ r = regmap_write(data->regmap, 0x0e, 0xA5);
+ if (r < 0)
+ return r;
+
+ r = regmap_write(data->regmap, 0x0f, 0x96);
+ if (r < 0)
+ return r;
+
+ r = regmap_write(data->regmap, 0x62, 0x02);
+ if (r < 0)
+ return r;
+
+ r = regmap_write(data->regmap, 0x0e, 0x00);
+ if (r < 0)
+ return r;
+
+ r = regmap_write(data->regmap, 0x0f, 0x00);
+
+ return r;
+}
+
static int dps310_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
@@ -383,6 +428,10 @@ static int dps310_probe(struct i2c_client *client,
if (r < 0)
goto err;
+ r = dps310_temp_workaround(data);
+ if (r < 0)
+ return r;
+
r = devm_iio_device_register(&client->dev, iio);
if (r)
goto err;
--
1.8.3.1
