| From e081102f3077aa716974ccebec97003c890d5641 Mon Sep 17 00:00:00 2001 |
| From: Alexandru Tachici <alexandru.tachici@analog.com> |
| Date: Mon, 6 Sep 2021 09:56:29 +0300 |
| Subject: iio: adc: ad7780: Fix IRQ flag |
| |
| From: Alexandru Tachici <alexandru.tachici@analog.com> |
| |
| commit e081102f3077aa716974ccebec97003c890d5641 upstream. |
| |
| Correct IRQ flag here is falling. |
| |
| 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 AD7780 datasheet: " The DOUT/Figure 22 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/20210906065630.16325-3-alexandru.tachici@analog.com |
| Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/iio/adc/ad7780.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/drivers/iio/adc/ad7780.c |
| +++ b/drivers/iio/adc/ad7780.c |
| @@ -203,7 +203,7 @@ static const struct ad_sigma_delta_info |
| .set_mode = ad7780_set_mode, |
| .postprocess_sample = ad7780_postprocess_sample, |
| .has_registers = false, |
| - .irq_flags = IRQF_TRIGGER_LOW, |
| + .irq_flags = IRQF_TRIGGER_FALLING, |
| }; |
| |
| #define _AD7780_CHANNEL(_bits, _wordsize, _mask_all) \ |
