irq: move doc to readme.

Cleanup, interlink, retest and update observations.

kernel_module/irq.c

@@ -1,42 +1,10 @@
-/*
-Brute force monitor every shared interrupt that will accept us.
-
-I.e. only works if for IRQs for which the other handlers are registered as IRQF_SHARED.
-
-Usage:
-
-1.  insmod and then use the keyboard and mouse. Those handlers are shared,
-	and the messages show up whenever you do something.
-
-	Does not work in text mode of course.
-
-2.  insmod some module that generates interrupts after insmod irq.,
-	e.g. pci_min or platform_device.
-
-	TODO: why does insmod in ARM lead to infinitely many interrupts handler irq = 45 dev = 252
-	and blocks the board? Is the ARM timer shared, and x86 isn't?
-
-TODO: properly understand how each IRQ maps to what.
-
-The Linux kernel mainline also has dummy-irq for monitoring a single IRQ.
-
-Inside QEMU, also try:
-
-	watch -n 1 cat /proc/interrupts
-
-Then see how clicking the mouse and keyboard affect the interrupts. This will point you to:
-
-- 1: keyboard
-- 12: mouse click and drags
-*/
-
 #include <linux/fs.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/uaccess.h> /* copy_from_user, copy_to_user */
 
-#define NAME "lkmc_character_device"
+#define NAME "lkmc_irq"
 #define MAX_IRQS 256
 
 static int irqs[MAX_IRQS];