I am using imx6 phyboard, I have interfaced an external ADC using SPI, I am accessing SPI using /dev/mem .
I will get an ADC Interrupt (high to low transition) once in very 90uSec. and I will read the samples data from ADC. I have configured a GPIO in interrupt mode and I am polling the status register to check whether interrupt has occurred or not ( There is no interrupt service routine) and every thing looks fine until here .
The time gap between each interrupt is 90uSec and most of the times imx6 is reading the samples data within 30usec, however some times imx6 is taking around 80uSec (or even more )to respond after interrupt has occurred and as a result data is getting missed - Here interrupt is not getting missed , it is served late.
I am suspecting whether my process is scheduled out by the operating system? Is there any method to block all other processes when I am reading ADC?
Please let me know your views.
Thanks in advance.