iio: adc: ad_sigma_delta: Fix IRQ issue by setting IRQ_DISABLE_UNLAZY flag

commit 626d312028bec44209d0ecd5beaa9b1aa8945f7d upstream.

The Sigma-Delta ADCs supported by this driver can use SDO as an interrupt
line to indicate the completion of a conversion. However, some devices
cannot properly detect the completion of a conversion by an interrupt.
This is for the reason mentioned in the following commit.

commit e9849777d0e2 ("genirq: Add flag to force mask in
                      disable_irq[_nosync]()")

A read operation is performed by an extra interrupt before the completion
of a conversion. At this time, the value read from the ADC data register
is the same as the previous conversion result. This patch fixes the issue
by setting IRQ_DISABLE_UNLAZY flag.

Fixes: 0c6ef985a1fd ("iio: adc: ad7791: fix IRQ flags")
Fixes: 1a913270e57a ("iio: adc: ad7793: Fix IRQ flag")
Fixes: e081102f3077 ("iio: adc: ad7780: Fix IRQ flag")
Fixes: 89a86da5cb8e ("iio: adc: ad7192: Add IRQ flag")
Fixes: 79ef91493f54 ("iio: adc: ad7124: Set IRQ type to falling")
Signed-off-by: Masahiro Honda <honda@mechatrax.com>
Link: https://lore.kernel.org/r/20230518110816.248-1-honda@mechatrax.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/iio/adc/ad_sigma_delta.c b/drivers/iio/adc/ad_sigma_delta.c
index d8570f6..7e21928 100644 (file)
--- a/drivers/iio/adc/ad_sigma_delta.c
+++ b/drivers/iio/adc/ad_sigma_delta.c
@@ -584,6 +584,10 @@ static int devm_ad_sd_probe_trigger(struct device *dev, struct iio_dev *indio_de
        init_completion(&sigma_delta->completion);
 
        sigma_delta->irq_dis = true;
+
+       /* the IRQ core clears IRQ_DISABLE_UNLAZY flag when freeing an IRQ */
+       irq_set_status_flags(sigma_delta->spi->irq, IRQ_DISABLE_UNLAZY);
+
        ret = devm_request_irq(dev, sigma_delta->spi->irq,
                               ad_sd_data_rdy_trig_poll,
                               sigma_delta->info->irq_flags | IRQF_NO_AUTOEN,