iio: trigger: Software Resend of Triggers

[Ibrahim Bagriyanik <ibrahim.bagriyanikb@gmail.com>]

Dear IIO Community,

I was developing a device driver for the MAX11040K ADC and have encountered an issue where the device begins sampling but stops after a few seconds. After debugging, I found that when an interrupt arrives while another trigger handler is still in progress -has not called iio_trigger_notify_done-, the poll calls seem to get lost.

As you know, the kernel provides the CONFIG_HARDIRQS_SW_RESEND option for software resends of IRQs. This feature masks IRQs in the control flow and resends them once the current IRQ handler finishes. I looked for a similar implementation in the IIO trigger source code but couldn't find anything.

Is there a similar mechanism within IIO, or how do others typically address this problem on slower processors? If there isn't, would implementing such a feature in IIO make sense? I tackled this by simply not using IIO triggers, and only thing I thought to make use of was simply blocking poll calls with synchronization primitives until the former trigger finishes. I would appreciate your thoughts and suggestions.

Best,
Ibrahim Bagriyanik.