| Message ID | 20240207033657.206171-1-demonsingur@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [1/2] iio: accel: adxl367: fix DEVID read after reset | expand |
On Wed, 2024-02-07 at 05:36 +0200, Cosmin Tanislav wrote: > regmap_read_poll_timeout() will not sleep before reading, > causing the first read to return -ENXIO on I2C, since the > chip does not respond to it while it is being reset. > > The datasheet specifies that a soft reset operation has a > latency of 7.5ms. > > Add a 15ms sleep between reset and reading the DEVID register, > and switch to a simple regmap_read() call. > > Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com> > --- This likely needs a Fixes: tag as well. With that, Reviewed-by: Nuno Sa <nuno.sa@analog.com> > drivers/iio/accel/adxl367.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/iio/accel/adxl367.c b/drivers/iio/accel/adxl367.c > index 834ee6d63947..210228affb80 100644 > --- a/drivers/iio/accel/adxl367.c > +++ b/drivers/iio/accel/adxl367.c > @@ -1368,9 +1368,11 @@ static int adxl367_verify_devid(struct adxl367_state > *st) > unsigned int val; > int ret; > > - ret = regmap_read_poll_timeout(st->regmap, ADXL367_REG_DEVID, val, > - val == ADXL367_DEVID_AD, 1000, 10000); > + ret = regmap_read(st->regmap, ADXL367_REG_DEVID, &val); > if (ret) > + return dev_err_probe(st->dev, ret, "Failed to read dev > id\n"); > + > + if (val != ADXL367_DEVID_AD) > return dev_err_probe(st->dev, -ENODEV, > "Invalid dev id 0x%02X, expected > 0x%02X\n", > val, ADXL367_DEVID_AD); > @@ -1449,6 +1451,8 @@ int adxl367_probe(struct device *dev, const struct > adxl367_ops *ops, > if (ret) > return ret; > > + fsleep(15000); > + > ret = adxl367_verify_devid(st); > if (ret) > return ret;
diff --git a/drivers/iio/accel/adxl367.c b/drivers/iio/accel/adxl367.c index 834ee6d63947..210228affb80 100644 --- a/drivers/iio/accel/adxl367.c +++ b/drivers/iio/accel/adxl367.c @@ -1368,9 +1368,11 @@ static int adxl367_verify_devid(struct adxl367_state *st) unsigned int val; int ret; - ret = regmap_read_poll_timeout(st->regmap, ADXL367_REG_DEVID, val, - val == ADXL367_DEVID_AD, 1000, 10000); + ret = regmap_read(st->regmap, ADXL367_REG_DEVID, &val); if (ret) + return dev_err_probe(st->dev, ret, "Failed to read dev id\n"); + + if (val != ADXL367_DEVID_AD) return dev_err_probe(st->dev, -ENODEV, "Invalid dev id 0x%02X, expected 0x%02X\n", val, ADXL367_DEVID_AD); @@ -1449,6 +1451,8 @@ int adxl367_probe(struct device *dev, const struct adxl367_ops *ops, if (ret) return ret; + fsleep(15000); + ret = adxl367_verify_devid(st); if (ret) return ret;
regmap_read_poll_timeout() will not sleep before reading, causing the first read to return -ENXIO on I2C, since the chip does not respond to it while it is being reset. The datasheet specifies that a soft reset operation has a latency of 7.5ms. Add a 15ms sleep between reset and reading the DEVID register, and switch to a simple regmap_read() call. Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com> --- drivers/iio/accel/adxl367.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)