Messages in this thread | | | From | richard clark <> | Date | Wed, 25 May 2022 18:01:26 +0800 | Subject | Question about SPIs' interrupt trigger type restrictions |
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Hi Marc,
For below code snippet about SPI interrupt trigger type:
static int gic_set_type(struct irq_data *d, unsigned int type) { ... /* SPIs have restrictions on the supported types */ if ((range == SPI_RANGE || range == ESPI_RANGE) && type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING) return -EINVAL; ... }
We have a device at hand whose interrupt type is SPI, Falling edge will trigger the interrupt. But the request_irq(50, handler, IRQ_TYPE_EDGE_FALLING, ...) will return -EINVAL.
The question is, why must the SPI interrupt use IRQ_TYPE_EDGE_RISING instead of IRQ_TYPE_EDGE_FALLING?
Thanks,
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