pxa270-rtc.c

pxa270的rtc驱动源代码！！好用！

/* drivers/char/pxa270_rtc.c
 *
 * Copyright (c) 2004 Simtec Electronics <[e-mail]>
 *		      http://www.simtec.co.uk/products/SWLINUX/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * PXA270 Internal RTC Driver
 *
 *  Changelog:
 *	08-Nov-2004	BJD	Initial creation
 *	12-Nov-2004	BJD	Added periodic IRQ and PM code
 *	22-Nov-2004	BJD	Sign-test on alarm code to check for <0
*/

#include <linux/module.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/rtc.h>
#include <linux/bcd.h>
#include <linux/delay.h>

#include <asm/hardware.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/rtc.h>

#include <asm/mach/time.h>

#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/timer.h>
#include <linux/jiffies.h>
#include <linux/config.h>
#include <linux/wait.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/notifier.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/reboot.h>

#include <asm/uaccess.h>
#include <asm/io.h>

#include <asm/hardware/clock.h>
#include <asm/arch/pxa-regs.h>

#include <asm-arm/delay.h>
/* need this for the RTC_AF definitions */
//#include <linux/mc146818rtc.h>

#undef PXA270_VA_RTC
#define PXA270_VA_RTC pxa270_rtc_base

#define DEBUG
static struct resource *pxa270_rtc_mem;

static void __iomem *pxa270_rtc_base;
static int pxa270_rtc_alarmno = NO_IRQ;
static int pxa270_rtc_tickno  = NO_IRQ;
static int pxa270_rtc_freq    = 1;

static spinlock_t pxa270_rtc_pie_lock = SPIN_LOCK_UNLOCKED;

/* IRQ Handlers */

static irqreturn_t pxa270_rtc_alarmirq(int irq, void *id, struct pt_regs *r)
{
///	rtc_update(1, RTC_AF | RTC_IRQF);
	return IRQ_HANDLED;
}

static irqreturn_t pxa270_rtc_tickirq(int irq, void *id, struct pt_regs *r)
{
///	rtc_update(1, RTC_PF | RTC_IRQF);
	return IRQ_HANDLED;
}

/* Update control registers */
static void pxa270_rtc_setaie(int to)
{
	unsigned int tmp;

	pr_debug("%s: aie=%d\n", __FUNCTION__, to);
#if 0
	tmp = readb(PXA270_RTCALM);

	if (to)
		tmp |= PXA270_RTCALM_ALMEN;
	else
		tmp &= ~PXA270_RTCALM_ALMEN;


	writeb(tmp, PXA270_RTCALM);
#endif
}

static void pxa270_rtc_setpie(int to)
{
	unsigned int tmp;

	pr_debug("%s: pie=%d\n", __FUNCTION__, to);
#if 0
	spin_lock_irq(&pxa270_rtc_pie_lock);
	tmp = readb(PXA270_TICNT) & ~PXA270_TICNT_ENABLE;

	if (to)
		tmp |= PXA270_TICNT_ENABLE;

	writeb(tmp, PXA270_TICNT);
	spin_unlock_irq(&pxa270_rtc_pie_lock);
#endif
}

static void pxa270_rtc_setfreq(int freq)
{
	unsigned int tmp;
#if 0
	spin_lock_irq(&pxa270_rtc_pie_lock);
	tmp = readb(PXA270_TICNT) & PXA270_TICNT_ENABLE;

	pxa270_rtc_freq = freq;

	tmp |= (128 / freq)-1;

	writeb(tmp, PXA270_TICNT);
	spin_unlock_irq(&pxa270_rtc_pie_lock);
#endif
}

/* Time read/write */

static void pxa270_rtc_gettime(struct rtc_time *rtc_tm)
/* Written by Kenan */
{
	rtc_tm->tm_sec  = (RDCR >>  0) & 0x3F;
	rtc_tm->tm_min  = (RDCR >>  6) & 0x3F;
	rtc_tm->tm_hour = (RDCR >> 12) & 0x1F;
	rtc_tm->tm_mday = (RYCR >>  0) & 0x1F;
	rtc_tm->tm_mon  = (RYCR >>  5) & 0xF;
	rtc_tm->tm_year = (RYCR >>  9) & 0xFFF; 
#if 0
	unsigned int have_retried = 0;
 retry_get_time:
	rtc_tm->tm_min  = readb(PXA270_RTCMIN);
	rtc_tm->tm_hour = readb(PXA270_RTCHOUR);
	rtc_tm->tm_mday = readb(PXA270_RTCDATE);
	rtc_tm->tm_mon  = readb(PXA270_RTCMON);
	rtc_tm->tm_year = readb(PXA270_RTCYEAR);
	rtc_tm->tm_sec  = readb(PXA270_RTCSEC);

	/* the only way to work out wether the system was mid-update
	 * when we read it is to check the second counter, and if it
	 * is zero, then we re-try the entire read
	 */

	if (rtc_tm->tm_sec == 0 && !have_retried) {
		have_retried = 1;
		goto retry_get_time;
	}

	pr_debug("read time %02x.%02x.%02x %02x/%02x/%02x\n",
		 rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
		 rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);

	BCD_TO_BIN(rtc_tm->tm_sec);
	BCD_TO_BIN(rtc_tm->tm_min);
	BCD_TO_BIN(rtc_tm->tm_hour);
	BCD_TO_BIN(rtc_tm->tm_mday);
	BCD_TO_BIN(rtc_tm->tm_mon);
	BCD_TO_BIN(rtc_tm->tm_year);

	rtc_tm->tm_year += 100;
	rtc_tm->tm_mon -= 1;
#endif
}


static int pxa270_rtc_settime(struct rtc_time *tm)
/* written by Kenan */
{
	/* the rtc gets round the y2k problem by just not supporting it */
	RYCR = ( (tm->tm_mday <<0) | (tm->tm_mon << 5) | (tm->tm_year <<9));
    RDCR = ( (tm->tm_sec  <<0) | (tm->tm_min << 6) | (tm->tm_hour << 12)); 
#if 0
	if (tm->tm_year < 100)
		return -EINVAL;

	writeb(BIN2BCD(tm->tm_sec),  PXA270_RTCSEC);
	writeb(BIN2BCD(tm->tm_min),  PXA270_RTCMIN);
	writeb(BIN2BCD(tm->tm_hour), PXA270_RTCHOUR);
	writeb(BIN2BCD(tm->tm_mday), PXA270_RTCDATE);
	writeb(BIN2BCD(tm->tm_mon + 1), PXA270_RTCMON);
	writeb(BIN2BCD(tm->tm_year - 100), PXA270_RTCYEAR);
#endif
	return 0;
}

static void pxa270_rtc_getalarm(struct rtc_wkalrm *alrm)
{
	struct rtc_time *alm_tm = &alrm->time;
	unsigned int alm_en;
#if 0
	printk("pxa270_rtc:RTTR=%2x\n",readb(RTTR));
	alm_tm->tm_sec  = readb(PXA270_ALMSEC);
	alm_tm->tm_min  = readb(PXA270_ALMMIN);
	alm_tm->tm_hour = readb(PXA270_ALMHOUR);
	alm_tm->tm_mon  = readb(PXA270_ALMMON);
	alm_tm->tm_mday = readb(PXA270_ALMDATE);
	alm_tm->tm_year = readb(PXA270_ALMYEAR);

	alm_en = readb(PXA270_RTCALM);

	pr_debug("read alarm %02x %02x.%02x.%02x %02x/%02x/%02x\n",
		 alm_en,
		 alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
		 alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);


	/* decode the alarm enable field */

	if (alm_en & PXA270_RTCALM_SECEN) {
		BCD_TO_BIN(alm_tm->tm_sec);
	} else {
		alm_tm->tm_sec = 0xff;
	}

	if (alm_en & PXA270_RTCALM_MINEN) {
		BCD_TO_BIN(alm_tm->tm_min);
	} else {
		alm_tm->tm_min = 0xff;
	}

	if (alm_en & PXA270_RTCALM_HOUREN) {
		BCD_TO_BIN(alm_tm->tm_hour);
	} else {
		alm_tm->tm_hour = 0xff;
	}

	if (alm_en & PXA270_RTCALM_DAYEN) {
		BCD_TO_BIN(alm_tm->tm_mday);
	} else {
		alm_tm->tm_mday = 0xff;
	}

	if (alm_en & PXA270_RTCALM_MONEN) {
		BCD_TO_BIN(alm_tm->tm_mon);
		alm_tm->tm_mon -= 1;
	} else {
		alm_tm->tm_mon = 0xff;
	}

	if (alm_en & PXA270_RTCALM_YEAREN) {
		BCD_TO_BIN(alm_tm->tm_year);
	} else {
		alm_tm->tm_year = 0xffff;
	}
#endif
	/* todo - set alrm->enabled ? */
}

static int pxa270_rtc_setalarm(struct rtc_wkalrm *alrm)
{
	struct rtc_time *tm = &alrm->time;
	unsigned int alrm_en;
#if 0
	pr_debug("pxa270_rtc_setalarm: %d, %02x/%02x/%02x %02x.%02x.%02x\n",
		 alrm->enabled,
		 tm->tm_mday & 0xff, tm->tm_mon & 0xff, tm->tm_year & 0xff,
		 tm->tm_hour & 0xff, tm->tm_min & 0xff, tm->tm_sec);

	if (alrm->enabled || 1) {
		alrm_en = readb(PXA270_RTCALM) & PXA270_RTCALM_ALMEN;
		writeb(0x00, PXA270_RTCALM);

		if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
			alrm_en |= PXA270_RTCALM_SECEN;
			writeb(BIN2BCD(tm->tm_sec), PXA270_ALMSEC);
		}

		if (tm->tm_min < 60 && tm->tm_min >= 0) {
			alrm_en |= PXA270_RTCALM_MINEN;
			writeb(BIN2BCD(tm->tm_min), PXA270_ALMMIN);
		}

		if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
			alrm_en |= PXA270_RTCALM_HOUREN;
			writeb(BIN2BCD(tm->tm_hour), PXA270_ALMHOUR);
		}

		pr_debug("setting PXA270_RTCALM to %08x\n", alrm_en);

		writeb(alrm_en, PXA270_RTCALM);
		enable_irq_wake(pxa270_rtc_alarmno);
	} else {
		alrm_en = readb(PXA270_RTCALM);
		alrm_en &= ~PXA270_RTCALM_ALMEN;
		writeb(alrm_en, PXA270_RTCALM);
		disable_irq_wake(pxa270_rtc_alarmno);
	}
#endif
	return 0;
}

static int pxa270_rtc_ioctl(unsigned int cmd, unsigned long arg)
{
#if 0
	switch (cmd) {
	case RTC_AIE_OFF:
	case RTC_AIE_ON:
		pxa270_rtc_setaie((cmd == RTC_AIE_ON) ? 1 : 0);
		return 0;

	case RTC_PIE_OFF:
	case RTC_PIE_ON:
		pxa270_rtc_setpie((cmd == RTC_PIE_ON) ? 1 : 0);
		return 0;

	case RTC_IRQP_READ:
		return put_user(pxa270_rtc_freq, (unsigned long __user *)arg);

	case RTC_IRQP_SET:
		if (arg < 1 || arg > 64)
			return -EINVAL;

		if (!capable(CAP_SYS_RESOURCE))
			return -EACCES;

		/* check for power of 2 */

		if ((arg & (arg-1)) != 0)