What is the difference between FIQ and IRQ interrupt system?
Jun 10, 2009 · An IRQ cannot interrupt the FIQ handler. The opposite is not true - the IRQ does not mask FIQs and so the FIQ handler (if used) can interrupt the IRQ. Additionally, if both IRQ …
Understanding kernel message 'nobody cared (try booting with …
Dec 13, 2012 · 21 I'm trying to understand the meaning of the following message: irq N:nobody cared (try booting with the "irqpoll" option) Does this mean the IRQ handler not processing the …
spin_lock_irqsave vs spin_lock_irq - Stack Overflow
Nov 26, 2015 · spin_lock_irqsave is basically used to save the interrupt state before taking the spin lock, this is because spin lock disables the interrupt, when the lock is taken in interrupt …
What limits the number of IRQ descriptors a Linux platform can …
Nov 18, 2024 · So I have an older hardware platform, which has a hard-coded NR_IRQS defined in the kernel to specify the number of available IRQ descriptors. This limit corresponds to the …
How to determine the IRQ number for a USB device?
May 18, 2013 · However, I am wondering how I would find what IRQ line (IRQ number) the device is interrupting on? That is, how do I determine what the value of the argument unsigned int irq …
Interrupt handling in Device Driver - Stack Overflow
The Same Interrupt number has to be mentioned in the Device Tree entry for instantiation of device driver. The Device driver's usual probe function parses the Device tree data structure …
c - What are the various ways to disable and re-enable interrupts …
Mar 26, 2022 · For an example look at the semaphore implementation in mbed-os. The other members of the STM32 family (STM32F0xx, STM32G0xx and STM32L0xx) may turn …
c - request_irq returns -22 (-EINVAL) - Stack Overflow
May 31, 2016 · Is it because of the irq number? Because after set the irq num to 10, I can register the irq successfully. The irq number 50 is not in /proc/interrupts, why can't I use it?
Interrupt-handling within kernel-module: request_irq() returns -22 ...
Aug 10, 2016 · request_irq(irqNumber, handler, 0, "GPIO_Test", NULL); but It returns -22, Invalid parameters. I think it might be the handler-function because I'm not sure about it's signature - …
What request_irq () does internally? - Stack Overflow
Dec 21, 2016 · what is happening after request_irq ()? A device driver registers an interrupt handler and enables a given interrupt line for handling by calling request_irq ().