ubuntu-linux-kernel/drivers/tty/hvc/hvc_irq.c

56 lines
1.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright IBM Corp. 2001,2008
*
* This file contains the IRQ specific code for hvc_console
*
*/
#include <linux/interrupt.h>
#include "hvc_console.h"
static irqreturn_t hvc_handle_interrupt(int irq, void *dev_instance)
{
/* if hvc_poll request a repoll, then kick the hvcd thread */
if (hvc_poll(dev_instance))
hvc_kick();
/*
* We're safe to always return IRQ_HANDLED as the hvcd thread will
* iterate through each hvc_struct.
*/
return IRQ_HANDLED;
}
/*
* For IRQ based systems these callbacks can be used
*/
int notifier_add_irq(struct hvc_struct *hp, int irq)
{
int rc;
if (!irq) {
hp->irq_requested = 0;
return 0;
}
rc = request_irq(irq, hvc_handle_interrupt, hp->flags,
"hvc_console", hp);
if (!rc)
hp->irq_requested = 1;
return rc;
}
void notifier_del_irq(struct hvc_struct *hp, int irq)
{
if (!hp->irq_requested)
return;
free_irq(irq, hp);
hp->irq_requested = 0;
}
void notifier_hangup_irq(struct hvc_struct *hp, int irq)
{
notifier_del_irq(hp, irq);
}