arm/mach-footbridge/isa-timer.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  *  linux/arch/arm/mach-footbridge/isa-timer.c
0004  *
0005  *  Copyright (C) 1998 Russell King.
0006  *  Copyright (C) 1998 Phil Blundell
0007  */
0008 #include <linux/clockchips.h>
0009 #include <linux/i8253.h>
0010 #include <linux/init.h>
0011 #include <linux/interrupt.h>
0012 #include <linux/irq.h>
0013 #include <linux/spinlock.h>
0014 #include <linux/timex.h>
0015
0016 #include <asm/irq.h>
0017 #include <asm/mach/time.h>
0018
0019 #include "common.h"
0020
0021 static irqreturn_t pit_timer_interrupt(int irq, void *dev_id)
0022 {
0023     struct clock_event_device *ce = dev_id;
0024     ce->event_handler(ce);
0025     return IRQ_HANDLED;
0026 }
0027
0028 void __init isa_timer_init(void)
0029 {
0030     clocksource_i8253_init();
0031
0032     if (request_irq(i8253_clockevent.irq, pit_timer_interrupt,
0033             IRQF_TIMER | IRQF_IRQPOLL, "pit", &i8253_clockevent))
0034         pr_err("Failed to request irq %d(pit)\n", i8253_clockevent.irq);
0035     clockevent_i8253_init(false);
0036 }