From: Alexandru Tachici alexandru.tachici@analog.com
commit 1a913270e57a8e7f1e3789802f1f64e6d0654626 upstream.
In Sigma-Delta devices the SDO line is also used as an interrupt. Leaving IRQ on level instead of falling might trigger a sample read when the IRQ is enabled, as the SDO line is already low. Not sure if SDO line will always immediately go high in ad_sd_buffer_postenable before the IRQ is enabled.
Also the datasheet seem to explicitly say the falling edge of the SDO should be used as an interrupt:
From the AD7793 datasheet: " The DOUT/RDY falling edge can be
used as an interrupt to a processor"
Fixes: da4d3d6bb9f6 ("iio: adc: ad-sigma-delta: Allow custom IRQ flags") Signed-off-by: Alexandru Tachici alexandru.tachici@analog.com Cc: Stable@vger.kernel.org Link: https://lore.kernel.org/r/20210906065630.16325-4-alexandru.tachici@analog.co... Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iio/adc/ad7793.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/iio/adc/ad7793.c +++ b/drivers/iio/adc/ad7793.c @@ -206,7 +206,7 @@ static const struct ad_sigma_delta_info .has_registers = true, .addr_shift = 3, .read_mask = BIT(6), - .irq_flags = IRQF_TRIGGER_LOW, + .irq_flags = IRQF_TRIGGER_FALLING, };
static const struct ad_sd_calib_data ad7793_calib_arr[6] = {