/* drivers/char/s3c2410_rtc.c * * Copyright (c) 2004 Simtec Electronics <linux@simtec.co.uk> * 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. * * S3C2410 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 * 10-Mar-2005 LCVR Changed S3C2410_VA_RTC to S3C24XX_VA_RTC */ #include <linux/module.h> #include <linux/fs.h> #include <linux/string.h> #include <linux/init.h> #include <linux/platform_device.h> #include <linux/interrupt.h> #include <linux/rtc.h> #include <linux/bcd.h> #include <linux/clk.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 <asm/arch/regs-rtc.h> /* need this for the RTC_AF definitions */ #include <linux/mc146818rtc.h> #undef S3C24XX_VA_RTC #define S3C24XX_VA_RTC s3c2410_rtc_base static struct resource *s3c2410_rtc_mem; static void __iomem *s3c2410_rtc_base; static int s3c2410_rtc_alarmno = NO_IRQ; static int s3c2410_rtc_tickno = NO_IRQ; static int s3c2410_rtc_freq = 1; static DEFINE_SPINLOCK(s3c2410_rtc_pie_lock); /* IRQ Handlers */ static irqreturn_t s3c2410_rtc_alarmirq(int irq, void *id, struct pt_regs *r) { rtc_update(1, RTC_AF | RTC_IRQF); return IRQ_HANDLED; } static irqreturn_t s3c2410_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 s3c2410_rtc_setaie(int to) { unsigned int tmp; pr_debug("%s: aie=%d\n", __FUNCTION__, to); tmp = readb(S3C2410_RTCALM); if (to) tmp |= S3C2410_RTCALM_ALMEN; else tmp &= ~S3C2410_RTCALM_ALMEN; writeb(tmp, S3C2410_RTCALM); } static void s3c2410_rtc_setpie(int to) { unsigned int tmp; pr_debug("%s: pie=%d\n", __FUNCTION__, to); spin_lock_irq(&s3c2410_rtc_pie_lock); tmp = readb(S3C2410_TICNT) & ~S3C2410_TICNT_ENABLE; if (to) tmp |= S3C2410_TICNT_ENABLE; writeb(tmp, S3C2410_TICNT); spin_unlock_irq(&s3c2410_rtc_pie_lock); } static void s3c2410_rtc_setfreq(int freq) { unsigned int tmp; spin_lock_irq(&s3c2410_rtc_pie_lock); tmp = readb(S3C2410_TICNT) & S3C2410_TICNT_ENABLE; s3c2410_rtc_freq = freq; tmp |= (128 / freq)-1; writeb(tmp, S3C2410_TICNT); spin_unlock_irq(&s3c2410_rtc_pie_lock); } /* Time read/write */ static int s3c2410_rtc_gettime(struct rtc_time *rtc_tm) { unsigned int have_retried = 0; retry_get_time: rtc_tm->tm_min = readb(S3C2410_RTCMIN); rtc_tm->tm_hour = readb(S3C2410_RTCHOUR); rtc_tm->tm_mday = readb(S3C2410_RTCDATE); rtc_tm->tm_mon = readb(S3C2410_RTCMON); rtc_tm->tm_year = readb(S3C2410_RTCYEAR); rtc_tm->tm_sec = readb(S3C2410_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; return 0; } static int s3c2410_rtc_settime(struct rtc_time *tm) { /* the rtc gets round the y2k problem by just not supporting it */ if (tm->tm_year < 100) return -EINVAL; writeb(BIN2BCD(tm->tm_sec), S3C2410_RTCSEC); writeb(BIN2BCD(tm->tm_min), S3C2410_RTCMIN); writeb(BIN2BCD(tm->tm_hour), S3C2410_RTCHOUR); writeb(BIN2BCD(tm->tm_mday), S3C2410_RTCDATE); writeb(BIN2BCD(tm->tm_mon + 1), S3C2410_RTCMON); writeb(BIN2BCD(tm->tm_year - 100), S3C2410_RTCYEAR); return 0; } static int s3c2410_rtc_getalarm(struct rtc_wkalrm *alrm) { struct rtc_time *alm_tm = &alrm->time; unsigned int alm_en; alm_tm->tm_sec = readb(S3C2410_ALMSEC); alm_tm->tm_min = readb(S3C2410_ALMMIN); alm_tm->tm_hour = readb(S3C2410_ALMHOUR); alm_tm->tm_mon = readb(S3C2410_ALMMON); alm_tm->tm_mday = readb(S3C2410_ALMDATE); alm_tm->tm_year = readb(S3C2410_ALMYEAR); alm_en = readb(S3C2410_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 & S3C2410_RTCALM_SECEN) { BCD_TO_BIN(alm_tm->tm_sec); } else { alm_tm->tm_sec = 0xff; } if (alm_en & S3C2410_RTCALM_MINEN) { BCD_TO_BIN(alm_tm->tm_min); } else { alm_tm->tm_min = 0xff; } if (alm_en & S3C2410_RTCALM_HOUREN) { BCD_TO_BIN(alm_tm->tm_hour); } else { alm_tm->tm_hour = 0xff; } if (alm_en & S3C2410_RTCALM_DAYEN) { BCD_TO_BIN(alm_tm->tm_mday); } else { alm_tm->tm_mday = 0xff; } if (alm_en & S3C2410_RTCALM_MONEN) { BCD_TO_BIN(alm_tm->tm_mon); alm_tm->tm_mon -= 1; } else { alm_tm->tm_mon = 0xff; } if (alm_en & S3C2410_RTCALM_YEAREN) { BCD_TO_BIN(alm_tm->tm_year); } else { alm_tm->tm_year = 0xffff; } /* todo - set alrm->enabled ? */ return 0; } static int s3c2410_rtc_setalarm(struct rtc_wkalrm *alrm) { struct rtc_time *tm = &alrm->time; unsigned int alrm_en; pr_debug("s3c2410_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(S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN; writeb(0x00, S3C2410_RTCALM); if (tm->tm_sec < 60 && tm->tm_sec >= 0) { alrm_en |= S3C2410_RTCALM_SECEN; writeb(BIN2BCD(tm->tm_sec), S3C2410_ALMSEC); } if (tm->tm_min < 60 && tm->tm_min >= 0) { alrm_en |= S3C2410_RTCALM_MINEN; writeb(BIN2BCD(tm->tm_min), S3C2410_ALMMIN); } if (tm->tm_hour < 24 && tm->tm_hour >= 0) { alrm_en |= S3C2410_RTCALM_HOUREN; writeb(BIN2BCD(tm->tm_hour), S3C2410_ALMHOUR); } pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en); writeb(alrm_en, S3C2410_RTCALM); enable_irq_wake(s3c2410_rtc_alarmno); } else { alrm_en = readb(S3C2410_RTCALM); alrm_en &= ~S3C2410_RTCALM_ALMEN; writeb(alrm_en, S3C2410_RTCALM); disable_irq_wake(s3c2410_rtc_alarmno); } return 0; } static int s3c2410_rtc_ioctl(unsigned int cmd, unsigned long arg) { switch (cmd) { case RTC_AIE_OFF: case RTC_AIE_ON: s3c2410_rtc_setaie((cmd == RTC_AIE_ON) ? 1 : 0); return 0; case RTC_PIE_OFF: case RTC_PIE_ON: s3c2410_rtc_setpie((cmd == RTC_PIE_ON) ? 1 : 0); return 0; case RTC_IRQP_READ: return put_user(s3c2410_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) return -EINVAL; pr_debug("s3c2410_rtc: setting frequency %ld\n", arg); s3c2410_rtc_setfreq(arg); return 0; case RTC_UIE_ON: case RTC_UIE_OFF: return -EINVAL; } return -EINVAL; } static int s3c2410_rtc_proc(char *buf) { unsigned int rtcalm = readb(S3C2410_RTCALM); unsigned int ticnt = readb (S3C2410_TICNT); char *p = buf; p += sprintf(p, "alarm_IRQ\t: %s\n", (rtcalm & S3C2410_RTCALM_ALMEN) ? "yes" : "no" ); p += sprintf(p, "periodic_IRQ\t: %s\n", (ticnt & S3C2410_TICNT_ENABLE) ? "yes" : "no" ); p += sprintf(p, "periodic_freq\t: %d\n", s3c2410_rtc_freq); return p - buf; } static int s3c2410_rtc_open(void) { int ret; ret = request_irq(s3c2410_rtc_alarmno, s3c2410_rtc_alarmirq, SA_INTERRUPT, "s3c2410-rtc alarm", NULL); if (ret) printk(KERN_ERR "IRQ%d already in use\n", s3c2410_rtc_alarmno); ret = request_irq(s3c2410_rtc_tickno, s3c2410_rtc_tickirq, SA_INTERRUPT, "s3c2410-rtc tick", NULL); if (ret) { printk(KERN_ERR "IRQ%d already in use\n", s3c2410_rtc_tickno); goto tick_err; } return ret; tick_err: free_irq(s3c2410_rtc_alarmno, NULL); return ret; } static void s3c2410_rtc_release(void) { /* do not clear AIE here, it may be needed for wake */ s3c2410_rtc_setpie(0); free_irq(s3c2410_rtc_alarmno, NULL); free_irq(s3c2410_rtc_tickno, NULL); } static struct rtc_ops s3c2410_rtcops = { .owner = THIS_MODULE, .open = s3c2410_rtc_open, .release = s3c2410_rtc_release, .ioctl = s3c2410_rtc_ioctl, .read_time = s3c2410_rtc_gettime, .set_time = s3c2410_rtc_settime, .read_alarm = s3c2410_rtc_getalarm, .set_alarm = s3c2410_rtc_setalarm, .proc = s3c2410_rtc_proc, }; static void s3c2410_rtc_enable(struct platform_device *pdev, int en) { unsigned int tmp; if (s3c2410_rtc_base == NULL) return; if (!en) { tmp = readb(S3C2410_RTCCON); writeb(tmp & ~S3C2410_RTCCON_RTCEN, S3C2410_RTCCON); tmp = readb(S3C2410_TICNT); writeb(tmp & ~S3C2410_TICNT_ENABLE, S3C2410_TICNT); } else { /* re-enable the device, and check it is ok */ if ((readb(S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0){ dev_info(&pdev->dev, "rtc disabled, re-enabling\n"); tmp = readb(S3C2410_RTCCON); writeb(tmp | S3C2410_RTCCON_RTCEN , S3C2410_RTCCON); } if ((readb(S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)){ dev_info(&pdev->dev, "removing S3C2410_RTCCON_CNTSEL\n"); tmp = readb(S3C2410_RTCCON); writeb(tmp& ~S3C2410_RTCCON_CNTSEL , S3C2410_RTCCON); } if ((readb(S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)){ dev_info(&pdev->dev, "removing S3C2410_RTCCON_CLKRST\n"); tmp = readb(S3C2410_RTCCON); writeb(tmp & ~S3C2410_RTCCON_CLKRST, S3C2410_RTCCON); } } } static int s3c2410_rtc_remove(struct platform_device *dev) { unregister_rtc(&s3c2410_rtcops); s3c2410_rtc_setpie(0); s3c2410_rtc_setaie(0); if (s3c2410_rtc_mem != NULL) { pr_debug("s3c2410_rtc: releasing s3c2410_rtc_mem\n"); iounmap(s3c2410_rtc_base); release_resource(s3c2410_rtc_mem); kfree(s3c2410_rtc_mem); } return 0; } static int s3c2410_rtc_probe(struct platform_device *pdev) { struct resource *res; int ret; pr_debug("%s: probe=%p\n", __FUNCTION__, pdev); /* find the IRQs */ s3c2410_rtc_tickno = platform_get_irq(pdev, 1); if (s3c2410_rtc_tickno <= 0) { dev_err(&pdev->dev, "no irq for rtc tick\n"); return -ENOENT; } s3c2410_rtc_alarmno = platform_get_irq(pdev, 0); if (s3c2410_rtc_alarmno <= 0) { dev_err(&pdev->dev, "no irq for alarm\n"); return -ENOENT; } pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n", s3c2410_rtc_tickno, s3c2410_rtc_alarmno); /* get the memory region */ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (res == NULL) { dev_err(&pdev->dev, "failed to get memory region resource\n"); return -ENOENT; } s3c2410_rtc_mem = request_mem_region(res->start, res->end-res->start+1, pdev->name); if (s3c2410_rtc_mem == NULL) { dev_err(&pdev->dev, "failed to reserve memory region\n"); ret = -ENOENT; goto exit_err; } s3c2410_rtc_base = ioremap(res->start, res->end - res->start + 1); if (s3c2410_rtc_base == NULL) { dev_err(&pdev->dev, "failed ioremap()\n"); ret = -EINVAL; goto exit_err; } s3c2410_rtc_mem = res; pr_debug("s3c2410_rtc_base=%p\n", s3c2410_rtc_base); pr_debug("s3c2410_rtc: RTCCON=%02x\n", readb(S3C2410_RTCCON)); /* check to see if everything is setup correctly */ s3c2410_rtc_enable(pdev, 1); pr_debug("s3c2410_rtc: RTCCON=%02x\n", readb(S3C2410_RTCCON)); s3c2410_rtc_setfreq(s3c2410_rtc_freq); /* register RTC and exit */ register_rtc(&s3c2410_rtcops); return 0; exit_err: dev_err(&pdev->dev, "error %d during initialisation\n", ret); return ret; } #ifdef CONFIG_PM /* S3C2410 RTC Power management control */ static struct timespec s3c2410_rtc_delta; static int ticnt_save; static int s3c2410_rtc_suspend(struct platform_device *pdev, pm_message_t state) { struct rtc_time tm; struct timespec time; time.tv_nsec = 0; /* save TICNT for anyone using periodic interrupts */ ticnt_save = readb(S3C2410_TICNT); /* calculate time delta for suspend */ s3c2410_rtc_gettime(&tm); rtc_tm_to_time(&tm, &time.tv_sec); save_time_delta(&s3c2410_rtc_delta, &time); s3c2410_rtc_enable(pdev, 0); return 0; } static int s3c2410_rtc_resume(struct platform_device *pdev) { struct rtc_time tm; struct timespec time; time.tv_nsec = 0; s3c2410_rtc_enable(pdev, 1); s3c2410_rtc_gettime(&tm); rtc_tm_to_time(&tm, &time.tv_sec); restore_time_delta(&s3c2410_rtc_delta, &time); writeb(ticnt_save, S3C2410_TICNT); return 0; } #else #define s3c2410_rtc_suspend NULL #define s3c2410_rtc_resume NULL #endif static struct platform_driver s3c2410_rtcdrv = { .probe = s3c2410_rtc_probe, .remove = s3c2410_rtc_remove, .suspend = s3c2410_rtc_suspend, .resume = s3c2410_rtc_resume, .driver = { .name = "s3c2410-rtc", .owner = THIS_MODULE, }, }; static char __initdata banner[] = "S3C2410 RTC, (c) 2004 Simtec Electronics\n"; static int __init s3c2410_rtc_init(void) { printk(banner); return platform_driver_register(&s3c2410_rtcdrv); } static void __exit s3c2410_rtc_exit(void) { platform_driver_unregister(&s3c2410_rtcdrv); } module_init(s3c2410_rtc_init); module_exit(s3c2410_rtc_exit); MODULE_DESCRIPTION("S3C24XX RTC Driver"); MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>"); MODULE_LICENSE("GPL");