From: Alison Schofield Date: Fri, 20 Jan 2017 20:22:58 +0000 (-0800) Subject: iio: pressure: ms5611: claim direct mode during oversampling changes X-Git-Tag: archive/raspbian/4.9.80-2+rpi1~7^2~1416 X-Git-Url: https://dgit.raspbian.org/%22http:/www.example.com/%22mailto:kde%40ewsoftware.de//%22style.css/%22/%22http:/www.example.com/%22mailto:kde%40ewsoftware.de/%22style.css/%22?a=commitdiff_plain;h=87e4965cec6156351892ecf45251c8dec03cc752;p=linux-4.9.git iio: pressure: ms5611: claim direct mode during oversampling changes [ Upstream commit 3bc1abcddb24f55b9c251e03caa4f9bd22ff748b ] Driver was checking for direct mode before changing oversampling ratios, but was not locking it. Use the claim/release helper functions to guarantee the device stays in direct mode while the oversampling ratios are being updated. Continue to use the drivers private state lock to protect against conflicting direct mode access of the state data. Signed-off-by: Alison Schofield Signed-off-by: Jonathan Cameron Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/iio/pressure/ms5611_core.c b/drivers/iio/pressure/ms5611_core.c index a74ed1f0c880..8cc7156b5ace 100644 --- a/drivers/iio/pressure/ms5611_core.c +++ b/drivers/iio/pressure/ms5611_core.c @@ -308,6 +308,7 @@ static int ms5611_write_raw(struct iio_dev *indio_dev, { struct ms5611_state *st = iio_priv(indio_dev); const struct ms5611_osr *osr = NULL; + int ret; if (mask != IIO_CHAN_INFO_OVERSAMPLING_RATIO) return -EINVAL; @@ -321,12 +322,11 @@ static int ms5611_write_raw(struct iio_dev *indio_dev, if (!osr) return -EINVAL; - mutex_lock(&st->lock); + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; - if (iio_buffer_enabled(indio_dev)) { - mutex_unlock(&st->lock); - return -EBUSY; - } + mutex_lock(&st->lock); if (chan->type == IIO_TEMP) st->temp_osr = osr; @@ -334,6 +334,8 @@ static int ms5611_write_raw(struct iio_dev *indio_dev, st->pressure_osr = osr; mutex_unlock(&st->lock); + iio_device_release_direct_mode(indio_dev); + return 0; }