diff options
author | Nuno Sá <nuno.sa@analog.com> | 2022-10-12 17:16:18 +0200 |
---|---|---|
committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2022-11-23 19:44:00 +0000 |
commit | 1555790c86286933dc674fffe9c1104250d093ce (patch) | |
tree | 80fa14754b9867df3abdce2abf634a4d5d63c946 /drivers | |
parent | 0a8565425afd8ba0e1a0ea73e21da119ee6dacea (diff) | |
download | linux-1555790c86286933dc674fffe9c1104250d093ce.tar.bz2 |
iio: health: max30100: do not use internal iio_dev lock
The pattern used in this device does not quite fit in the
iio_device_claim_direct_mode() typical usage. In this case,
iio_buffer_enabled() was being used not to prevent the raw
access but to allow it. Hence, let's make use of the new
iio_device_claim_buffer_mode() API to make sure we stay in
buffered mode during the complete read.
Note that we are shadowing the error code returned by
iio_device_claim_buffer_mode() so that we keep the original one
(-EAGAIN). The reason is that some userspace stack might already be
relying on this particular code so that we are not taking chances and
leave it alone.
Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20221012151620.1725215-3-nuno.sa@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/iio/health/max30100.c | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/drivers/iio/health/max30100.c b/drivers/iio/health/max30100.c index 2cca5e0519f8..3aa5d037a1c3 100644 --- a/drivers/iio/health/max30100.c +++ b/drivers/iio/health/max30100.c @@ -387,18 +387,21 @@ static int max30100_read_raw(struct iio_dev *indio_dev, * Temperature reading can only be acquired while engine * is running */ - mutex_lock(&indio_dev->mlock); - - if (!iio_buffer_enabled(indio_dev)) + if (iio_device_claim_buffer_mode(indio_dev)) { + /* + * Replacing -EBUSY or other error code + * returned by iio_device_claim_buffer_mode() + * because user space may rely on the current + * one. + */ ret = -EAGAIN; - else { + } else { ret = max30100_get_temp(data, val); if (!ret) ret = IIO_VAL_INT; + iio_device_release_buffer_mode(indio_dev); } - - mutex_unlock(&indio_dev->mlock); break; case IIO_CHAN_INFO_SCALE: *val = 1; /* 0.0625 */ |