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Release 4.14 drivers/rtc/rtc-vr41xx.c

Directory: drivers/rtc
/*
 *  Driver for NEC VR4100 series Real Time Clock unit.
 *
 *  Copyright (C) 2003-2008  Yoichi Yuasa <yuasa@linux-mips.org>
 *
 *  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include <linux/err.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <linux/uaccess.h>
#include <linux/log2.h>

#include <asm/div64.h>

MODULE_AUTHOR("Yoichi Yuasa <yuasa@linux-mips.org>");
MODULE_DESCRIPTION("NEC VR4100 series RTC driver");
MODULE_LICENSE("GPL v2");

/* RTC 1 registers */

#define ETIMELREG		0x00

#define ETIMEMREG		0x02

#define ETIMEHREG		0x04
/* RFU */

#define ECMPLREG		0x08

#define ECMPMREG		0x0a

#define ECMPHREG		0x0c
/* RFU */

#define RTCL1LREG		0x10

#define RTCL1HREG		0x12

#define RTCL1CNTLREG		0x14

#define RTCL1CNTHREG		0x16

#define RTCL2LREG		0x18

#define RTCL2HREG		0x1a

#define RTCL2CNTLREG		0x1c

#define RTCL2CNTHREG		0x1e

/* RTC 2 registers */

#define TCLKLREG		0x00

#define TCLKHREG		0x02

#define TCLKCNTLREG		0x04

#define TCLKCNTHREG		0x06
/* RFU */

#define RTCINTREG		0x1e
 
#define TCLOCK_INT		0x08
 
#define RTCLONG2_INT		0x04
 
#define RTCLONG1_INT		0x02
 
#define ELAPSEDTIME_INT	0x01


#define RTC_FREQUENCY		32768

#define MAX_PERIODIC_RATE	6553


static void __iomem *rtc1_base;

static void __iomem *rtc2_base;


#define rtc1_read(offset)		readw(rtc1_base + (offset))

#define rtc1_write(offset, value)	writew((value), rtc1_base + (offset))


#define rtc2_read(offset)		readw(rtc2_base + (offset))

#define rtc2_write(offset, value)	writew((value), rtc2_base + (offset))


static unsigned long epoch = 1970;	
/* Jan 1 1970 00:00:00 */

static DEFINE_SPINLOCK(rtc_lock);

static char rtc_name[] = "RTC";

static unsigned long periodic_count;

static unsigned int alarm_enabled;

static int aie_irq;

static int pie_irq;


static inline unsigned long read_elapsed_second(void) { unsigned long first_low, first_mid, first_high; unsigned long second_low, second_mid, second_high; do { first_low = rtc1_read(ETIMELREG); first_mid = rtc1_read(ETIMEMREG); first_high = rtc1_read(ETIMEHREG); second_low = rtc1_read(ETIMELREG); second_mid = rtc1_read(ETIMEMREG); second_high = rtc1_read(ETIMEHREG); } while (first_low != second_low || first_mid != second_mid || first_high != second_high); return (first_high << 17) | (first_mid << 1) | (first_low >> 15); }

Contributors

PersonTokensPropCommitsCommitProp
Yoichi Yuasa105100.00%1100.00%
Total105100.00%1100.00%


static inline void write_elapsed_second(unsigned long sec) { spin_lock_irq(&rtc_lock); rtc1_write(ETIMELREG, (uint16_t)(sec << 15)); rtc1_write(ETIMEMREG, (uint16_t)(sec >> 1)); rtc1_write(ETIMEHREG, (uint16_t)(sec >> 17)); spin_unlock_irq(&rtc_lock); }

Contributors

PersonTokensPropCommitsCommitProp
Yoichi Yuasa65100.00%1100.00%
Total65100.00%1100.00%


static int vr41xx_rtc_read_time(struct device *dev, struct rtc_time *time) { unsigned long epoch_sec, elapsed_sec; epoch_sec = mktime(epoch, 1, 1, 0, 0, 0); elapsed_sec = read_elapsed_second(); rtc_time_to_tm(epoch_sec + elapsed_sec, time); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Yoichi Yuasa56100.00%2100.00%
Total56100.00%2100.00%


static int vr41xx_rtc_set_time(struct device *dev, struct rtc_time *time) { unsigned long epoch_sec, current_sec; epoch_sec = mktime(epoch, 1, 1, 0, 0, 0); current_sec = mktime(time->tm_year + 1900, time->tm_mon + 1, time->tm_mday, time->tm_hour, time->tm_min, time->tm_sec); write_elapsed_second(current_sec - epoch_sec); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Yoichi Yuasa82100.00%2100.00%
Total82100.00%2100.00%


static int vr41xx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm) { unsigned long low, mid, high; struct rtc_time *time = &wkalrm->time; spin_lock_irq(&rtc_lock); low = rtc1_read(ECMPLREG); mid = rtc1_read(ECMPMREG); high = rtc1_read(ECMPHREG); wkalrm->enabled = alarm_enabled; spin_unlock_irq(&rtc_lock); rtc_time_to_tm((high << 17) | (mid << 1) | (low >> 15), time); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Yoichi Yuasa99100.00%3100.00%
Total99100.00%3100.00%


static int vr41xx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm) { unsigned long alarm_sec; struct rtc_time *time = &wkalrm->time; alarm_sec = mktime(time->tm_year + 1900, time->tm_mon + 1, time->tm_mday, time->tm_hour, time->tm_min, time->tm_sec); spin_lock_irq(&rtc_lock); if (alarm_enabled) disable_irq(aie_irq); rtc1_write(ECMPLREG, (uint16_t)(alarm_sec << 15)); rtc1_write(ECMPMREG, (uint16_t)(alarm_sec >> 1)); rtc1_write(ECMPHREG, (uint16_t)(alarm_sec >> 17)); if (wkalrm->enabled) enable_irq(aie_irq); alarm_enabled = wkalrm->enabled; spin_unlock_irq(&rtc_lock); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Yoichi Yuasa146100.00%4100.00%
Total146100.00%4100.00%


static int vr41xx_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) { switch (cmd) { case RTC_EPOCH_READ: return put_user(epoch, (unsigned long __user *)arg); case RTC_EPOCH_SET: /* Doesn't support before 1900 */ if (arg < 1900) return -EINVAL; epoch = arg; break; default: return -ENOIOCTLCMD; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
John Stultz4463.77%133.33%
Yoichi Yuasa2536.23%266.67%
Total69100.00%3100.00%


static int vr41xx_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) { spin_lock_irq(&rtc_lock); if (enabled) { if (!alarm_enabled) { enable_irq(aie_irq); alarm_enabled = 1; } } else { if (alarm_enabled) { disable_irq(aie_irq); alarm_enabled = 0; } } spin_unlock_irq(&rtc_lock); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Yoichi Yuasa4767.14%480.00%
John Stultz2332.86%120.00%
Total70100.00%5100.00%


static irqreturn_t elapsedtime_interrupt(int irq, void *dev_id) { struct platform_device *pdev = (struct platform_device *)dev_id; struct rtc_device *rtc = platform_get_drvdata(pdev); rtc2_write(RTCINTREG, ELAPSEDTIME_INT); rtc_update_irq(rtc, 1, RTC_AF); return IRQ_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
Yoichi Yuasa54100.00%2100.00%
Total54100.00%2100.00%


static irqreturn_t rtclong1_interrupt(int irq, void *dev_id) { struct platform_device *pdev = (struct platform_device *)dev_id; struct rtc_device *rtc = platform_get_drvdata(pdev); unsigned long count = periodic_count; rtc2_write(RTCINTREG, RTCLONG1_INT); rtc1_write(RTCL1LREG, count); rtc1_write(RTCL1HREG, count >> 16); rtc_update_irq(rtc, 1, RTC_PF); return IRQ_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
Yoichi Yuasa76100.00%2100.00%
Total76100.00%2100.00%

static const struct rtc_class_ops vr41xx_rtc_ops = { .ioctl = vr41xx_rtc_ioctl, .read_time = vr41xx_rtc_read_time, .set_time = vr41xx_rtc_set_time, .read_alarm = vr41xx_rtc_read_alarm, .set_alarm = vr41xx_rtc_set_alarm, .alarm_irq_enable = vr41xx_rtc_alarm_irq_enable, };
static int rtc_probe(struct platform_device *pdev) { struct resource *res; struct rtc_device *rtc; int retval; if (pdev->num_resources != 4) return -EBUSY; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) return -EBUSY; rtc1_base = devm_ioremap(&pdev->dev, res->start, resource_size(res)); if (!rtc1_base) return -EBUSY; res = platform_get_resource(pdev, IORESOURCE_MEM, 1); if (!res) { retval = -EBUSY; goto err_rtc1_iounmap; } rtc2_base = devm_ioremap(&pdev->dev, res->start, resource_size(res)); if (!rtc2_base) { retval = -EBUSY; goto err_rtc1_iounmap; } rtc = devm_rtc_device_register(&pdev->dev, rtc_name, &vr41xx_rtc_ops, THIS_MODULE); if (IS_ERR(rtc)) { retval = PTR_ERR(rtc); goto err_iounmap_all; } rtc->max_user_freq = MAX_PERIODIC_RATE; spin_lock_irq(&rtc_lock); rtc1_write(ECMPLREG, 0); rtc1_write(ECMPMREG, 0); rtc1_write(ECMPHREG, 0); rtc1_write(RTCL1LREG, 0); rtc1_write(RTCL1HREG, 0); spin_unlock_irq(&rtc_lock); aie_irq = platform_get_irq(pdev, 0); if (aie_irq <= 0) { retval = -EBUSY; goto err_iounmap_all; } retval = devm_request_irq(&pdev->dev, aie_irq, elapsedtime_interrupt, 0, "elapsed_time", pdev); if (retval < 0) goto err_iounmap_all; pie_irq = platform_get_irq(pdev, 1); if (pie_irq <= 0) { retval = -EBUSY; goto err_iounmap_all; } retval = devm_request_irq(&pdev->dev, pie_irq, rtclong1_interrupt, 0, "rtclong1", pdev); if (retval < 0) goto err_iounmap_all; platform_set_drvdata(pdev, rtc); disable_irq(aie_irq); disable_irq(pie_irq); dev_info(&pdev->dev, "Real Time Clock of NEC VR4100 series\n"); return 0; err_iounmap_all: rtc2_base = NULL; err_rtc1_iounmap: rtc1_base = NULL; return retval; }

Contributors

PersonTokensPropCommitsCommitProp
Yoichi Yuasa33586.79%545.45%
Jingoo Han389.84%218.18%
Wei Yongjun71.81%19.09%
Russell King20.52%19.09%
Yong Zhang20.52%19.09%
Anton Vorontsov20.52%19.09%
Total386100.00%11100.00%

/* work with hotplug and coldplug */ MODULE_ALIAS("platform:RTC"); static struct platform_driver rtc_platform_driver = { .probe = rtc_probe, .driver = { .name = rtc_name, }, }; module_platform_driver(rtc_platform_driver);

Overall Contributors

PersonTokensPropCommitsCommitProp
Yoichi Yuasa137590.16%735.00%
John Stultz674.39%15.00%
Jingoo Han382.49%210.00%
Russell King100.66%15.00%
Wei Yongjun70.46%15.00%
Sachin Kamat60.39%15.00%
Kay Sievers60.39%15.00%
Geert Uytterhoeven50.33%15.00%
Ingo Molnar40.26%15.00%
Axel Lin20.13%15.00%
Yong Zhang20.13%15.00%
Anton Vorontsov20.13%15.00%
David Brownell10.07%15.00%
Total1525100.00%20100.00%
Directory: drivers/rtc
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