| /* |
| * Real Time Clock interface for Linux on Atmel AT91RM9200 |
| * |
| * Copyright (C) 2002 Rick Bronson |
| * |
| * Converted to RTC class model by Andrew Victor |
| * |
| * Ported to Linux 2.6 by Steven Scholz |
| * Based on s3c2410-rtc.c Simtec Electronics |
| * |
| * Based on sa1100-rtc.c by Nils Faerber |
| * Based on rtc.c by Paul Gortmaker |
| * |
| * 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. |
| * |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/kernel.h> |
| #include <linux/platform_device.h> |
| #include <linux/time.h> |
| #include <linux/rtc.h> |
| #include <linux/bcd.h> |
| #include <linux/interrupt.h> |
| #include <linux/ioctl.h> |
| #include <linux/completion.h> |
| |
| #include <asm/uaccess.h> |
| #include <asm/rtc.h> |
| |
| #include <asm/mach/time.h> |
| |
| |
| #define AT91_RTC_FREQ 1 |
| #define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */ |
| |
| static DECLARE_COMPLETION(at91_rtc_updated); |
| static unsigned int at91_alarm_year = AT91_RTC_EPOCH; |
| |
| |
| /* |
| * Decode time/date into rtc_time structure |
| */ |
| static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg, struct rtc_time *tm) |
| { |
| unsigned int time, date; |
| |
| /* must read twice in case it changes */ |
| do { |
| time = at91_sys_read(timereg); |
| date = at91_sys_read(calreg); |
| } while ((time != at91_sys_read(timereg)) || (date != at91_sys_read(calreg))); |
| |
| tm->tm_sec = BCD2BIN((time & AT91_RTC_SEC) >> 0); |
| tm->tm_min = BCD2BIN((time & AT91_RTC_MIN) >> 8); |
| tm->tm_hour = BCD2BIN((time & AT91_RTC_HOUR) >> 16); |
| |
| /* |
| * The Calendar Alarm register does not have a field for |
| * the year - so these will return an invalid value. When an |
| * alarm is set, at91_alarm_year wille store the current year. |
| */ |
| tm->tm_year = BCD2BIN(date & AT91_RTC_CENT) * 100; /* century */ |
| tm->tm_year += BCD2BIN((date & AT91_RTC_YEAR) >> 8); /* year */ |
| |
| tm->tm_wday = BCD2BIN((date & AT91_RTC_DAY) >> 21) - 1; /* day of the week [0-6], Sunday=0 */ |
| tm->tm_mon = BCD2BIN((date & AT91_RTC_MONTH) >> 16) - 1; |
| tm->tm_mday = BCD2BIN((date & AT91_RTC_DATE) >> 24); |
| } |
| |
| /* |
| * Read current time and date in RTC |
| */ |
| static int at91_rtc_readtime(struct device *dev, struct rtc_time *tm) |
| { |
| at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm); |
| tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); |
| tm->tm_year = tm->tm_year - 1900; |
| |
| pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __FUNCTION__, |
| 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec); |
| |
| return 0; |
| } |
| |
| /* |
| * Set current time and date in RTC |
| */ |
| static int at91_rtc_settime(struct device *dev, struct rtc_time *tm) |
| { |
| unsigned long cr; |
| |
| pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __FUNCTION__, |
| 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec); |
| |
| /* Stop Time/Calendar from counting */ |
| cr = at91_sys_read(AT91_RTC_CR); |
| at91_sys_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM); |
| |
| at91_sys_write(AT91_RTC_IER, AT91_RTC_ACKUPD); |
| wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */ |
| at91_sys_write(AT91_RTC_IDR, AT91_RTC_ACKUPD); |
| |
| at91_sys_write(AT91_RTC_TIMR, |
| BIN2BCD(tm->tm_sec) << 0 |
| | BIN2BCD(tm->tm_min) << 8 |
| | BIN2BCD(tm->tm_hour) << 16); |
| |
| at91_sys_write(AT91_RTC_CALR, |
| BIN2BCD((tm->tm_year + 1900) / 100) /* century */ |
| | BIN2BCD(tm->tm_year % 100) << 8 /* year */ |
| | BIN2BCD(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */ |
| | BIN2BCD(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */ |
| | BIN2BCD(tm->tm_mday) << 24); |
| |
| /* Restart Time/Calendar */ |
| cr = at91_sys_read(AT91_RTC_CR); |
| at91_sys_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM)); |
| |
| return 0; |
| } |
| |
| /* |
| * Read alarm time and date in RTC |
| */ |
| static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm) |
| { |
| struct rtc_time *tm = &alrm->time; |
| |
| at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm); |
| tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); |
| tm->tm_year = at91_alarm_year - 1900; |
| |
| pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __FUNCTION__, |
| 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec); |
| |
| return 0; |
| } |
| |
| /* |
| * Set alarm time and date in RTC |
| */ |
| static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm) |
| { |
| struct rtc_time tm; |
| |
| at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm); |
| |
| at91_alarm_year = tm.tm_year; |
| |
| tm.tm_hour = alrm->time.tm_hour; |
| tm.tm_min = alrm->time.tm_min; |
| tm.tm_sec = alrm->time.tm_sec; |
| |
| at91_sys_write(AT91_RTC_TIMALR, |
| BIN2BCD(tm.tm_sec) << 0 |
| | BIN2BCD(tm.tm_min) << 8 |
| | BIN2BCD(tm.tm_hour) << 16 |
| | AT91_RTC_HOUREN | AT91_RTC_MINEN | AT91_RTC_SECEN); |
| at91_sys_write(AT91_RTC_CALALR, |
| BIN2BCD(tm.tm_mon + 1) << 16 /* tm_mon starts at zero */ |
| | BIN2BCD(tm.tm_mday) << 24 |
| | AT91_RTC_DATEEN | AT91_RTC_MTHEN); |
| |
| pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __FUNCTION__, |
| at91_alarm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec); |
| |
| return 0; |
| } |
| |
| /* |
| * Handle commands from user-space |
| */ |
| static int at91_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) |
| { |
| int ret = 0; |
| |
| pr_debug("%s(): cmd=%08x, arg=%08lx.\n", __FUNCTION__, cmd, arg); |
| |
| switch (cmd) { |
| case RTC_AIE_OFF: /* alarm off */ |
| at91_sys_write(AT91_RTC_IDR, AT91_RTC_ALARM); |
| break; |
| case RTC_AIE_ON: /* alarm on */ |
| at91_sys_write(AT91_RTC_IER, AT91_RTC_ALARM); |
| break; |
| case RTC_UIE_OFF: /* update off */ |
| case RTC_PIE_OFF: /* periodic off */ |
| at91_sys_write(AT91_RTC_IDR, AT91_RTC_SECEV); |
| break; |
| case RTC_UIE_ON: /* update on */ |
| case RTC_PIE_ON: /* periodic on */ |
| at91_sys_write(AT91_RTC_IER, AT91_RTC_SECEV); |
| break; |
| case RTC_IRQP_READ: /* read periodic alarm frequency */ |
| ret = put_user(AT91_RTC_FREQ, (unsigned long *) arg); |
| break; |
| case RTC_IRQP_SET: /* set periodic alarm frequency */ |
| if (arg != AT91_RTC_FREQ) |
| ret = -EINVAL; |
| break; |
| default: |
| ret = -ENOIOCTLCMD; |
| break; |
| } |
| |
| return ret; |
| } |
| |
| /* |
| * Provide additional RTC information in /proc/driver/rtc |
| */ |
| static int at91_rtc_proc(struct device *dev, struct seq_file *seq) |
| { |
| unsigned long imr = at91_sys_read(AT91_RTC_IMR); |
| |
| seq_printf(seq, "alarm_IRQ\t: %s\n", (imr & AT91_RTC_ALARM) ? "yes" : "no"); |
| seq_printf(seq, "update_IRQ\t: %s\n", (imr & AT91_RTC_ACKUPD) ? "yes" : "no"); |
| seq_printf(seq, "periodic_IRQ\t: %s\n", (imr & AT91_RTC_SECEV) ? "yes" : "no"); |
| seq_printf(seq, "periodic_freq\t: %ld\n", (unsigned long) AT91_RTC_FREQ); |
| |
| return 0; |
| } |
| |
| /* |
| * IRQ handler for the RTC |
| */ |
| static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs) |
| { |
| struct platform_device *pdev = (struct platform_device *)dev_id; |
| struct rtc_device *rtc = platform_get_drvdata(pdev); |
| unsigned int rtsr; |
| unsigned long events = 0; |
| |
| rtsr = at91_sys_read(AT91_RTC_SR) & at91_sys_read(AT91_RTC_IMR); |
| if (rtsr) { /* this interrupt is shared! Is it ours? */ |
| if (rtsr & AT91_RTC_ALARM) |
| events |= (RTC_AF | RTC_IRQF); |
| if (rtsr & AT91_RTC_SECEV) |
| events |= (RTC_UF | RTC_IRQF); |
| if (rtsr & AT91_RTC_ACKUPD) |
| complete(&at91_rtc_updated); |
| |
| at91_sys_write(AT91_RTC_SCCR, rtsr); /* clear status reg */ |
| |
| rtc_update_irq(&rtc->class_dev, 1, events); |
| |
| pr_debug("%s(): num=%ld, events=0x%02lx\n", __FUNCTION__, |
| events >> 8, events & 0x000000FF); |
| |
| return IRQ_HANDLED; |
| } |
| return IRQ_NONE; /* not handled */ |
| } |
| |
| static struct rtc_class_ops at91_rtc_ops = { |
| .ioctl = at91_rtc_ioctl, |
| .read_time = at91_rtc_readtime, |
| .set_time = at91_rtc_settime, |
| .read_alarm = at91_rtc_readalarm, |
| .set_alarm = at91_rtc_setalarm, |
| .proc = at91_rtc_proc, |
| }; |
| |
| /* |
| * Initialize and install RTC driver |
| */ |
| static int __init at91_rtc_probe(struct platform_device *pdev) |
| { |
| struct rtc_device *rtc; |
| int ret; |
| |
| at91_sys_write(AT91_RTC_CR, 0); |
| at91_sys_write(AT91_RTC_MR, 0); /* 24 hour mode */ |
| |
| /* Disable all interrupts */ |
| at91_sys_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM | AT91_RTC_SECEV | AT91_RTC_TIMEV | AT91_RTC_CALEV); |
| |
| ret = request_irq(AT91_ID_SYS, at91_rtc_interrupt, SA_SHIRQ, "at91_rtc", pdev); |
| if (ret) { |
| printk(KERN_ERR "at91_rtc: IRQ %d already in use.\n", AT91_ID_SYS); |
| return ret; |
| } |
| |
| rtc = rtc_device_register(pdev->name, &pdev->dev, &at91_rtc_ops, THIS_MODULE); |
| if (IS_ERR(rtc)) { |
| free_irq(AT91_ID_SYS, pdev); |
| return PTR_ERR(rtc); |
| } |
| platform_set_drvdata(pdev, rtc); |
| |
| printk(KERN_INFO "AT91 Real Time Clock driver.\n"); |
| return 0; |
| } |
| |
| /* |
| * Disable and remove the RTC driver |
| */ |
| static int __devexit at91_rtc_remove(struct platform_device *pdev) |
| { |
| struct rtc_device *rtc = platform_get_drvdata(pdev); |
| |
| /* Disable all interrupts */ |
| at91_sys_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM | AT91_RTC_SECEV | AT91_RTC_TIMEV | AT91_RTC_CALEV); |
| free_irq(AT91_ID_SYS, pdev); |
| |
| rtc_device_unregister(rtc); |
| platform_set_drvdata(pdev, NULL); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM |
| |
| /* AT91RM9200 RTC Power management control */ |
| |
| static struct timespec at91_rtc_delta; |
| |
| static int at91_rtc_suspend(struct platform_device *pdev, pm_message_t state) |
| { |
| struct rtc_time tm; |
| struct timespec time; |
| |
| time.tv_nsec = 0; |
| |
| /* calculate time delta for suspend */ |
| at91_rtc_readtime(&pdev->dev, &tm); |
| rtc_tm_to_time(&tm, &time.tv_sec); |
| save_time_delta(&at91_rtc_delta, &time); |
| |
| pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __FUNCTION__, |
| 1900 + tm.tm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec); |
| |
| return 0; |
| } |
| |
| static int at91_rtc_resume(struct platform_device *pdev) |
| { |
| struct rtc_time tm; |
| struct timespec time; |
| |
| time.tv_nsec = 0; |
| |
| at91_rtc_readtime(&pdev->dev, &tm); |
| rtc_tm_to_time(&tm, &time.tv_sec); |
| restore_time_delta(&at91_rtc_delta, &time); |
| |
| pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __FUNCTION__, |
| 1900 + tm.tm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec); |
| |
| return 0; |
| } |
| #else |
| #define at91_rtc_suspend NULL |
| #define at91_rtc_resume NULL |
| #endif |
| |
| static struct platform_driver at91_rtc_driver = { |
| .probe = at91_rtc_probe, |
| .remove = at91_rtc_remove, |
| .suspend = at91_rtc_suspend, |
| .resume = at91_rtc_resume, |
| .driver = { |
| .name = "at91_rtc", |
| .owner = THIS_MODULE, |
| }, |
| }; |
| |
| static int __init at91_rtc_init(void) |
| { |
| return platform_driver_register(&at91_rtc_driver); |
| } |
| |
| static void __exit at91_rtc_exit(void) |
| { |
| platform_driver_unregister(&at91_rtc_driver); |
| } |
| |
| |
| module_init(at91_rtc_init); |
| module_exit(at91_rtc_exit); |
| |
| MODULE_AUTHOR("Rick Bronson"); |
| MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200"); |
| MODULE_LICENSE("GPL"); |