remarkable-linux/include/linux/irqreturn.h
Geert Uytterhoeven 6bab2c613d genirq: Correct fuzzy and fragile IRQ_RETVAL() definition
commit bedd30d986 ("genirq: make irqreturn_t an enum") blindly replaced
"0" by "IRQ_NONE" in the "IRQ_RETVAL(x)" macro definition.

However, as "x" is a condition, "0" meant "boolean false", not an
irqreturn_t value.

All of this worked, and kept working after the addition of IRQ_WAKE_THREAD,
as
  - both "boolean false" and "IRQ_NONE" are "0" (for the comparison),
  - "boolean true" and "boolean false" nicely map to the correct values of
    "IRQ_HANDLED" and "IRQ_NONE" (for the return value).

Correct the macro definition for clarity and future-proofness.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-11-19 19:06:41 +01:00

20 lines
445 B
C

#ifndef _LINUX_IRQRETURN_H
#define _LINUX_IRQRETURN_H
/**
* enum irqreturn
* @IRQ_NONE interrupt was not from this device
* @IRQ_HANDLED interrupt was handled by this device
* @IRQ_WAKE_THREAD handler requests to wake the handler thread
*/
enum irqreturn {
IRQ_NONE = (0 << 0),
IRQ_HANDLED = (1 << 0),
IRQ_WAKE_THREAD = (1 << 1),
};
typedef enum irqreturn irqreturn_t;
#define IRQ_RETVAL(x) ((x) ? IRQ_HANDLED : IRQ_NONE)
#endif