From b77e5d0b4e8ae7d107717b12aab2967684c00a59 Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Fri, 3 Apr 2020 15:27:14 +0200 Subject: [PATCH] iio: xilinx-xadc: Fix clearing interrupt when enabling trigger commit f954b098fbac4d183219ce5b42d76d6df2aed50a upstream. When enabling the trigger and unmasking the end-of-sequence (EOS) interrupt the EOS interrupt should be cleared from the status register. Otherwise it is possible that it was still set from a previous capture. If that is the case the interrupt would fire immediately even though no conversion has been done yet and stale data is being read from the device. The old code only clears the interrupt if the interrupt was previously unmasked. Which does not make much sense since the interrupt is always masked at this point and in addition masking the interrupt does not clear the interrupt from the status register. So the clearing needs to be done unconditionally. Signed-off-by: Lars-Peter Clausen Fixes: bdc8cda1d010 ("iio:adc: Add Xilinx XADC driver") Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman --- drivers/iio/adc/xilinx-xadc-core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/iio/adc/xilinx-xadc-core.c b/drivers/iio/adc/xilinx-xadc-core.c index 744f8ffe6b8d..aa3560ec0779 100644 --- a/drivers/iio/adc/xilinx-xadc-core.c +++ b/drivers/iio/adc/xilinx-xadc-core.c @@ -660,7 +660,7 @@ static int xadc_trigger_set_state(struct iio_trigger *trigger, bool state) spin_lock_irqsave(&xadc->lock, flags); xadc_read_reg(xadc, XADC_AXI_REG_IPIER, &val); - xadc_write_reg(xadc, XADC_AXI_REG_IPISR, val & XADC_AXI_INT_EOS); + xadc_write_reg(xadc, XADC_AXI_REG_IPISR, XADC_AXI_INT_EOS); if (state) val |= XADC_AXI_INT_EOS; else