diff options
| author | Petre Rodan <petre.rodan@subdimension.ro> | 2026-01-14 19:55:40 +0300 |
|---|---|---|
| committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2026-01-16 20:40:41 +0300 |
| commit | 84e15e1a6e103e5b57852d90ac686d7f0d0d8b0a (patch) | |
| tree | f76d34f63f8d15399237d961d745ddc55d6aca9d | |
| parent | 4edab7b08783f06679de0d24318d92ffc1dfd537 (diff) | |
| download | linux-84e15e1a6e103e5b57852d90ac686d7f0d0d8b0a.tar.xz | |
iio: pressure: mprls0025pa: stricter checks for the status byte
Make sure a valid conversion comes with a status byte that only has
the MPR_ST_POWER bit set.
Return -EBUSY if also MPR_ST_BUSY is set or -EIO otherwise.
Reviewed-by: Marcelo Schmitt <marcelo.schmitt1@gmail.com>
Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
| -rw-r--r-- | drivers/iio/pressure/mprls0025pa.c | 28 |
1 files changed, 22 insertions, 6 deletions
diff --git a/drivers/iio/pressure/mprls0025pa.c b/drivers/iio/pressure/mprls0025pa.c index a7041a503bde..31ec2bae84b1 100644 --- a/drivers/iio/pressure/mprls0025pa.c +++ b/drivers/iio/pressure/mprls0025pa.c @@ -198,9 +198,10 @@ static void mpr_reset(struct mpr_data *data) * * Context: The function can sleep and data->lock should be held when calling it * Return: - * * 0 - OK, the pressure value could be read - * * -ETIMEDOUT - Timeout while waiting for the EOC interrupt or busy flag is - * still set after nloops attempts of reading + * * 0 - OK, the pressure value could be read + * * -EBUSY - Sensor does not have a new conversion ready + * * -ETIMEDOUT - Timeout while waiting for the EOC interrupt + * * -EIO - Invalid status byte received from sensor */ static int mpr_read_pressure(struct mpr_data *data, s32 *press) { @@ -253,10 +254,25 @@ static int mpr_read_pressure(struct mpr_data *data, s32 *press) if (ret < 0) return ret; - if (data->rx_buf[0] & MPR_ST_ERR_FLAG) { + /* + * Status byte flags + * bit7 SANITY_CHK - must always be 0 + * bit6 MPR_ST_POWER - 1 if device is powered + * bit5 MPR_ST_BUSY - 1 if device has no new conversion ready + * bit4 SANITY_CHK - must always be 0 + * bit3 SANITY_CHK - must always be 0 + * bit2 MEMORY_ERR - 1 if integrity test has failed + * bit1 SANITY_CHK - must always be 0 + * bit0 MATH_ERR - 1 during internal math saturation error + */ + + if (data->rx_buf[0] == (MPR_ST_POWER | MPR_ST_BUSY)) + return -EBUSY; + + if (data->rx_buf[0] != MPR_ST_POWER) { dev_err(data->dev, - "unexpected status byte %02x\n", data->rx_buf[0]); - return -ETIMEDOUT; + "unexpected status byte 0x%02x\n", data->rx_buf[0]); + return -EIO; } *press = get_unaligned_be24(&data->rx_buf[1]); |