arch/arm/mach-footbridge/isa-timer.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/arch/arm/mach-footbridge/isa-timer.c
   4  *
   5  *  Copyright (C) 1998 Russell King.
   6  *  Copyright (C) 1998 Phil Blundell
   7  */
   8 #include <linux/clockchips.h>
   9 #include <linux/i8253.h>
  10 #include <linux/init.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/irq.h>
  13 #include <linux/spinlock.h>
  14 #include <linux/timex.h>
  15
  16 #include <asm/irq.h>
  17 #include <asm/mach/time.h>
  18
  19 #include "common.h"
  20
  21 static irqreturn_t pit_timer_interrupt(int irq, void *dev_id)
  22 {
  23         struct clock_event_device *ce = dev_id;
  24         ce->event_handler(ce);
  25         return IRQ_HANDLED;
  26 }
  27
  28 void __init isa_timer_init(void)
  29 {
  30         clocksource_i8253_init();
  31
  32         if (request_irq(i8253_clockevent.irq, pit_timer_interrupt,
  33                         IRQF_TIMER | IRQF_IRQPOLL, "pit", &i8253_clockevent))
  34                 pr_err("Failed to request irq %d(pit)\n", i8253_clockevent.irq);
  35         clockevent_i8253_init(false);
  36 }