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![Thomas Gleixner](/assets/img/avatar_default.png)
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin street fifth floor boston ma 02110 1301 usa this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option [no]_[pad]_[ctrl] any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin street fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 176 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com> Reviewed-by: Steve Winslow <swinslow@gmail.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190519154040.652910950@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
126 lines
2.4 KiB
C
126 lines
2.4 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* DS1287 clockevent driver
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*
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* Copyright (C) 2008 Yoichi Yuasa <yuasa@linux-mips.org>
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*/
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#include <linux/clockchips.h>
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#include <linux/init.h>
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#include <linux/interrupt.h>
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#include <linux/mc146818rtc.h>
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#include <linux/irq.h>
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#include <asm/time.h>
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int ds1287_timer_state(void)
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{
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return (CMOS_READ(RTC_REG_C) & RTC_PF) != 0;
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}
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int ds1287_set_base_clock(unsigned int hz)
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{
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u8 rate;
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switch (hz) {
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case 128:
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rate = 0x9;
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break;
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case 256:
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rate = 0x8;
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break;
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case 1024:
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rate = 0x6;
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break;
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default:
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return -EINVAL;
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}
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CMOS_WRITE(RTC_REF_CLCK_32KHZ | rate, RTC_REG_A);
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return 0;
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}
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static int ds1287_set_next_event(unsigned long delta,
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struct clock_event_device *evt)
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{
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return -EINVAL;
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}
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static int ds1287_shutdown(struct clock_event_device *evt)
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{
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u8 val;
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spin_lock(&rtc_lock);
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val = CMOS_READ(RTC_REG_B);
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val &= ~RTC_PIE;
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CMOS_WRITE(val, RTC_REG_B);
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spin_unlock(&rtc_lock);
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return 0;
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}
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static int ds1287_set_periodic(struct clock_event_device *evt)
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{
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u8 val;
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spin_lock(&rtc_lock);
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val = CMOS_READ(RTC_REG_B);
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val |= RTC_PIE;
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CMOS_WRITE(val, RTC_REG_B);
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spin_unlock(&rtc_lock);
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return 0;
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}
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static void ds1287_event_handler(struct clock_event_device *dev)
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{
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}
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static struct clock_event_device ds1287_clockevent = {
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.name = "ds1287",
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.features = CLOCK_EVT_FEAT_PERIODIC,
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.set_next_event = ds1287_set_next_event,
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.set_state_shutdown = ds1287_shutdown,
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.set_state_periodic = ds1287_set_periodic,
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.tick_resume = ds1287_shutdown,
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.event_handler = ds1287_event_handler,
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};
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static irqreturn_t ds1287_interrupt(int irq, void *dev_id)
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{
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struct clock_event_device *cd = &ds1287_clockevent;
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/* Ack the RTC interrupt. */
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CMOS_READ(RTC_REG_C);
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cd->event_handler(cd);
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return IRQ_HANDLED;
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}
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static struct irqaction ds1287_irqaction = {
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.handler = ds1287_interrupt,
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.flags = IRQF_PERCPU | IRQF_TIMER,
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.name = "ds1287",
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};
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int __init ds1287_clockevent_init(int irq)
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{
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struct clock_event_device *cd;
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cd = &ds1287_clockevent;
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cd->rating = 100;
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cd->irq = irq;
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clockevent_set_clock(cd, 32768);
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cd->max_delta_ns = clockevent_delta2ns(0x7fffffff, cd);
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cd->max_delta_ticks = 0x7fffffff;
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cd->min_delta_ns = clockevent_delta2ns(0x300, cd);
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cd->min_delta_ticks = 0x300;
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cd->cpumask = cpumask_of(0);
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clockevents_register_device(&ds1287_clockevent);
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return setup_irq(irq, &ds1287_irqaction);
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}
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