Driver was checking for direct mode and trying to lock it, but left a gap where mode could change before the desired operation. Use iio_device_claim_direct_mode() to guarantee device stays in direct mode.
Signed-off-by: Alison Schofield <[email protected]> Cc: Daniel Baluta <[email protected]> --- drivers/iio/adc/ad7791.c | 15 ++++----------- 1 file changed, 4 insertions(+), 11 deletions(-) diff --git a/drivers/iio/adc/ad7791.c b/drivers/iio/adc/ad7791.c index cf172d58..f7edacc 100644 --- a/drivers/iio/adc/ad7791.c +++ b/drivers/iio/adc/ad7791.c @@ -272,24 +272,17 @@ static ssize_t ad7791_write_frequency(struct device *dev, struct ad7791_state *st = iio_priv(indio_dev); int i, ret; - mutex_lock(&indio_dev->mlock); - if (iio_buffer_enabled(indio_dev)) { - mutex_unlock(&indio_dev->mlock); - return -EBUSY; - } - mutex_unlock(&indio_dev->mlock); - - ret = -EINVAL; - for (i = 0; i < ARRAY_SIZE(ad7791_sample_freq_avail); i++) { if (sysfs_streq(ad7791_sample_freq_avail[i], buf)) { - mutex_lock(&indio_dev->mlock); + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; st->filter &= ~AD7791_FILTER_RATE_MASK; st->filter |= i; ad_sd_write_reg(&st->sd, AD7791_REG_FILTER, sizeof(st->filter), st->filter); - mutex_unlock(&indio_dev->mlock); + iio_device_release_direct_mode(indio_dev); ret = 0; break; } -- 2.1.4
