• Thomas Gleixner's avatar
    genirq: add threaded interrupt handler support · 3aa551c9
    Thomas Gleixner authored
    Add support for threaded interrupt handlers:
    
    A device driver can request that its main interrupt handler runs in a
    thread. To achive this the device driver requests the interrupt with
    request_threaded_irq() and provides additionally to the handler a
    thread function. The handler function is called in hard interrupt
    context and needs to check whether the interrupt originated from the
    device. If the interrupt originated from the device then the handler
    can either return IRQ_HANDLED or IRQ_WAKE_THREAD. IRQ_HANDLED is
    returned when no further action is required. IRQ_WAKE_THREAD causes
    the genirq code to invoke the threaded (main) handler. When
    IRQ_WAKE_THREAD is returned handler must have disabled the interrupt
    on the device level. This is mandatory for shared interrupt handlers,
    but we need to do it as well for obscure x86 hardware where disabling
    an interrupt on the IO_APIC level redirects the interrupt to the
    legacy PIC interrupt lines.
    Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
    Reviewed-by: default avatarIngo Molnar <mingo@elte.hu>
    3aa551c9
handle.c 12.1 KB