> Even though we are passing 'ret' as stop condition for
> read_poll_timeout(), that return code is still being ignored. The reason
> is that the poll will stop if the passed condition is true which will
> happen if the passed op() returns error. However, read_poll_timeout()
> returns 0 if the *complete* condition evaluates to true. Therefore, the
> error code returned by op() will be ignored.
>
> To fix this we need to check for both error codes:
> * The one returned by read_poll_timeout() which is either 0 or
> ETIMEDOUT.
> * The one returned by the passed op().
>
> Fixes: a44ef7c46097 ("iio: adc: add max11410 adc driver")
> Signed-off-by: Nuno Sá <nuno.sa@xxxxxxxxxx>
Acked-by: Ibrahim Tilki <Ibrahim.Tilki@xxxxxxxxxx>
> ---
> drivers/iio/adc/max11410.c | 22 +++++++++++++++-------
> 1 file changed, 15 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/iio/adc/max11410.c b/drivers/iio/adc/max11410.c
> index 237b2ce3f264..6af829349b4e 100644
> --- a/drivers/iio/adc/max11410.c
> +++ b/drivers/iio/adc/max11410.c
> @@ -414,13 +414,17 @@ static int max11410_sample(struct max11410_state *st, int *sample_raw,
> if (!ret)
> return -ETIMEDOUT;
> } else {
> + int ret2;
> +
> /* Wait for status register Conversion Ready flag */
> - ret = read_poll_timeout(max11410_read_reg, ret,
> - ret || (val & MAX11410_STATUS_CONV_READY_BIT),
> + ret = read_poll_timeout(max11410_read_reg, ret2,
> + ret2 || (val & MAX11410_STATUS_CONV_READY_BIT),
> 5000, MAX11410_CONVERSION_TIMEOUT_MS * 1000,
> true, st, MAX11410_REG_STATUS, &val);
> if (ret)
> return ret;
> + if (ret2)
> + return ret2;
> }
>
> /* Read ADC Data */
> @@ -851,17 +855,21 @@ static int max11410_init_vref(struct device *dev,
>
> static int max11410_calibrate(struct max11410_state *st, u32 cal_type)
> {
> - int ret, val;
> + int ret, ret2, val;
>
> ret = max11410_write_reg(st, MAX11410_REG_CAL_START, cal_type);
> if (ret)
> return ret;
>
> /* Wait for status register Calibration Ready flag */
> - return read_poll_timeout(max11410_read_reg, ret,
> - ret || (val & MAX11410_STATUS_CAL_READY_BIT),
> - 50000, MAX11410_CALIB_TIMEOUT_MS * 1000, true,
> - st, MAX11410_REG_STATUS, &val);
> + ret = read_poll_timeout(max11410_read_reg, ret2,
> + ret2 || (val & MAX11410_STATUS_CAL_READY_BIT),
> + 50000, MAX11410_CALIB_TIMEOUT_MS * 1000, true,
> + st, MAX11410_REG_STATUS, &val);
> + if (ret)
> + return ret;
> +
> + return ret2;
> }
>
> static int max11410_self_calibrate(struct max11410_state *st)
