From: Nuno Sá Date: Tue, 20 Sep 2022 11:28:07 +0000 (+0200) Subject: iio: adc: ad_sigma_delta: do not use internal iio_dev lock X-Git-Tag: v5.15.92~750 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=aec1058f2a92f1ab24eac96fc100df793e35a93f;p=platform%2Fkernel%2Flinux-rpi.git iio: adc: ad_sigma_delta: do not use internal iio_dev lock commit 20228a1d5a55e7db0c6720840f2c7d2b48c55f69 upstream. Drop 'mlock' usage by making use of iio_device_claim_direct_mode(). This change actually makes sure we cannot do a single conversion while buffering is enable. Note there was a potential race in the previous code since we were only acquiring the lock after checking if the bus is enabled. Fixes: af3008485ea0 ("iio:adc: Add common code for ADI Sigma Delta devices") Signed-off-by: Nuno Sá Reviewed-by: Miquel Raynal Cc: #No rush as race is very old. Link: https://lore.kernel.org/r/20220920112821.975359-2-nuno.sa@analog.com Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/iio/adc/ad_sigma_delta.c b/drivers/iio/adc/ad_sigma_delta.c index 1d652d9b..bd5c495 100644 --- a/drivers/iio/adc/ad_sigma_delta.c +++ b/drivers/iio/adc/ad_sigma_delta.c @@ -280,10 +280,10 @@ int ad_sigma_delta_single_conversion(struct iio_dev *indio_dev, unsigned int data_reg; int ret = 0; - if (iio_buffer_enabled(indio_dev)) - return -EBUSY; + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; - mutex_lock(&indio_dev->mlock); ad_sigma_delta_set_channel(sigma_delta, chan->address); spi_bus_lock(sigma_delta->spi->master); @@ -322,7 +322,7 @@ out: ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_IDLE); sigma_delta->bus_locked = false; spi_bus_unlock(sigma_delta->spi->master); - mutex_unlock(&indio_dev->mlock); + iio_device_release_direct_mode(indio_dev); if (ret) return ret;