/* drivers/rtc/rtc-s3c.c * * Copyright (c) 2004,2006 Simtec Electronics * Ben Dooks, <ben@simtec.co.uk> * http://armlinux.simtec.co.uk/ * * 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/S3C2440/S3C24XX Internal RTC Driver */ #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> /* I have yet to find an S3C implementation with more than one * of these rtc blocks in */ static struct resource *s3c_rtc_mem; static void __iomem *s3c_rtc_base; static int s3c_rtc_alarmno = NO_IRQ; static int s3c_rtc_tickno = NO_IRQ; static int s3c_rtc_freq = 1; static DEFINE_SPINLOCK(s3c_rtc_pie_lock); static unsigned int tick_count; /* IRQ Handlers */ static irqreturn_t s3c_rtc_alarmirq(int irq, void *id) { struct rtc_device *rdev = id; rtc_update_irq(rdev, 1, RTC_AF | RTC_IRQF); return IRQ_HANDLED; } static irqreturn_t s3c_rtc_tickirq(int irq, void *id) { struct rtc_device *rdev = id; rtc_update_irq(rdev, tick_count++, RTC_PF | RTC_IRQF); return IRQ_HANDLED; } /* Update control registers */ static void s3c_rtc_setaie(int to) { unsigned int tmp; pr_debug("%s: aie=%d\n", __FUNCTION__, to); tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN; if (to) tmp |= S3C2410_RTCALM_ALMEN; writeb(tmp, s3c_rtc_base + S3C2410_RTCALM); } static void s3c_rtc_setpie(int to) { unsigned int tmp; pr_debug("%s: pie=%d\n", __FUNCTION__, to); spin_lock_irq(&s3c_rtc_pie_lock); tmp = readb(s3c_rtc_base + S3C2410_TICNT) & ~S3C2410_TICNT_ENABLE; if (to) tmp |= S3C2410_TICNT_ENABLE; writeb(tmp, s3c_rtc_base + S3C2410_TICNT); spin_unlock_irq(&s3c_rtc_pie_lock); } static void s3c_rtc_setfreq(int freq) { unsigned int tmp; spin_lock_irq(&s3c_rtc_pie_lock); tmp = readb(s3c_rtc_base + S3C2410_TICNT) & S3C2410_TICNT_ENABLE; s3c_rtc_freq = freq; tmp |= (128 / freq)-1; writeb(tmp, s3c_rtc_base + S3C2410_TICNT); spin_unlock_irq(&s3c_rtc_pie_lock); } /* Time read/write */ static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm) { unsigned int have_retried = 0; void __iomem *base = s3c_rtc_base; retry_get_time: rtc_tm->tm_min = readb(base + S3C2410_RTCMIN); rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR); rtc_tm->tm_mday = readb(base + S3C2410_RTCDATE); rtc_tm->tm_mon = readb(base + S3C2410_RTCMON); rtc_tm->tm_year = readb(base + S3C2410_RTCYEAR); rtc_tm->tm_sec = readb(base + 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 s3c_rtc_settime(struct device *dev, struct rtc_time *tm) { void __iomem *base = s3c_rtc_base; int year = tm->tm_year - 100; pr_debug("set time %02d.%02d.%02d %02d/%02d/%02d\n", tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec); /* we get around y2k by simply not supporting it */ if (year < 0 || year >= 100) { dev_err(dev, "rtc only supports 100 years\n"); return -EINVAL; } writeb(BIN2BCD(tm->tm_sec), base + S3C2410_RTCSEC); writeb(BIN2BCD(tm->tm_min), base + S3C2410_RTCMIN); writeb(BIN2BCD(tm->tm_hour), base + S3C2410_RTCHOUR); writeb(BIN2BCD(tm->tm_mday), base + S3C2410_RTCDATE); writeb(BIN2BCD(tm->tm_mon + 1), base + S3C2410_RTCMON); writeb(BIN2BCD(year), base + S3C2410_RTCYEAR); return 0; } static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm) { struct rtc_time *alm_tm = &alrm->time; void __iomem *base = s3c_rtc_base; unsigned int alm_en; alm_tm->tm_sec = readb(base + S3C2410_ALMSEC); alm_tm->tm_min = readb(base + S3C2410_ALMMIN); alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR); alm_tm->tm_mon = readb(base + S3C2410_ALMMON); alm_tm->tm_mday = readb(base + S3C2410_ALMDATE); alm_tm->tm_year = readb(base + S3C2410_ALMYEAR); alm_en = readb(base + S3C2410_RTCALM); alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0; 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; return 0; } static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm) { struct rtc_time *tm = &alrm->time; void __iomem *base = s3c_rtc_base; unsigned int alrm_en; pr_debug("s3c_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); alrm_en = readb(base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN; writeb(0x00, base + S3C2410_RTCALM); if (tm->tm_sec < 60 && tm->tm_sec >= 0) { alrm_en |= S3C2410_RTCALM_SECEN; writeb(BIN2BCD(tm->tm_sec), base + S3C2410_ALMSEC); } if (tm->tm_min < 60 && tm->tm_min >= 0) { alrm_en |= S3C2410_RTCALM_MINEN; writeb(BIN2BCD(tm->tm_min), base + S3C2410_ALMMIN); } if (tm->tm_hour < 24 && tm->tm_hour >= 0) { alrm_en |= S3C2410_RTCALM_HOUREN; writeb(BIN2BCD(tm->tm_hour), base + S3C2410_ALMHOUR); } pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en); writeb(alrm_en, base + S3C2410_RTCALM); if (0) { alrm_en = readb(base + S3C2410_RTCALM); alrm_en &= ~S3C2410_RTCALM_ALMEN; writeb(alrm_en, base + S3C2410_RTCALM); disable_irq_wake(s3c_rtc_alarmno); } if (alrm->enabled) enable_irq_wake(s3c_rtc_alarmno); else disable_irq_wake(s3c_rtc_alarmno); return 0; } static int s3c_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) { unsigned int ret = -ENOIOCTLCMD; switch (cmd) { case RTC_AIE_OFF: case RTC_AIE_ON: s3c_rtc_setaie((cmd == RTC_AIE_ON) ? 1 : 0); ret = 0; break; case RTC_PIE_OFF: case RTC_PIE_ON: tick_count = 0; s3c_rtc_setpie((cmd == RTC_PIE_ON) ? 1 : 0); ret = 0; break; case RTC_IRQP_READ: ret = put_user(s3c_rtc_freq, (unsigned long __user *)arg); break; case RTC_IRQP_SET: /* check for power of 2 */ if ((arg & (arg-1)) != 0 || arg < 1) { ret = -EINVAL; goto exit; } pr_debug("s3c2410_rtc: setting frequency %ld\n", arg); s3c_rtc_setfreq(arg); ret = 0; break; case RTC_UIE_ON: case RTC_UIE_OFF: ret = -EINVAL; } exit: return ret; } static int s3c_rtc_proc(struct device *dev, struct seq_file *seq) { unsigned int ticnt = readb(s3c_rtc_base + S3C2410_TICNT); seq_printf(seq, "periodic_IRQ\t: %s\n", (ticnt & S3C2410_TICNT_ENABLE) ? "yes" : "no" ); seq_printf(seq, "periodic_freq\t: %d\n", s3c_rtc_freq); return 0; } static int s3c_rtc_open(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct rtc_device *rtc_dev = platform_get_drvdata(pdev); int ret; ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq, IRQF_DISABLED, "s3c2410-rtc alarm", rtc_dev); if (ret) { dev_err(dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret); return ret; } ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq, IRQF_DISABLED, "s3c2410-rtc tick", rtc_dev); if (ret) { dev_err(dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret); goto tick_err; } return ret; tick_err: free_irq(s3c_rtc_alarmno, rtc_dev); return ret; } static void s3c_rtc_release(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct rtc_device *rtc_dev = platform_get_drvdata(pdev); /* do not clear AIE here, it may be needed for wake */ s3c_rtc_setpie(0); free_irq(s3c_rtc_alarmno, rtc_dev); free_irq(s3c_rtc_tickno, rtc_dev); } static const struct rtc_class_ops s3c_rtcops = { .open = s3c_rtc_open, .release = s3c_rtc_release, .ioctl = s3c_rtc_ioctl, .read_time = s3c_rtc_gettime, .set_time = s3c_rtc_settime, .read_alarm = s3c_rtc_getalarm, .set_alarm = s3c_rtc_setalarm, .proc = s3c_rtc_proc, }; static void s3c_rtc_enable(struct platform_device *pdev, int en) { void __iomem *base = s3c_rtc_base; unsigned int tmp; if (s3c_rtc_base == NULL) return; if (!en) { tmp = readb(base + S3C2410_RTCCON); writeb(tmp & ~S3C2410_RTCCON_RTCEN, base + S3C2410_RTCCON); tmp = readb(base + S3C2410_TICNT); writeb(tmp & ~S3C2410_TICNT_ENABLE, base + S3C2410_TICNT); } else { /* re-enable the device, and check it is ok */ if ((readb(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0){ dev_info(&pdev->dev, "rtc disabled, re-enabling\n"); tmp = readb(base + S3C2410_RTCCON); writeb(tmp|S3C2410_RTCCON_RTCEN, base+S3C2410_RTCCON); } if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)){ dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n"); tmp = readb(base + S3C2410_RTCCON); writeb(tmp& ~S3C2410_RTCCON_CNTSEL, base+S3C2410_RTCCON); } if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)){ dev_info(&pdev->dev, "removing RTCCON_CLKRST\n"); tmp = readb(base + S3C2410_RTCCON); writeb(tmp & ~S3C2410_RTCCON_CLKRST, base+S3C2410_RTCCON); } } } static int s3c_rtc_remove(struct platform_device *dev) { struct rtc_device *rtc = platform_get_drvdata(dev); platform_set_drvdata(dev, NULL); rtc_device_unregister(rtc); s3c_rtc_setpie(0); s3c_rtc_setaie(0); iounmap(s3c_rtc_base); release_resource(s3c_rtc_mem); kfree(s3c_rtc_mem); return 0; } static int s3c_rtc_probe(struct platform_device *pdev) { struct rtc_device *rtc; struct resource *res; int ret; pr_debug("%s: probe=%p\n", __FUNCTION__, pdev); /* find the IRQs */ s3c_rtc_tickno = platform_get_irq(pdev, 1); if (s3c_rtc_tickno < 0) { dev_err(&pdev->dev, "no irq for rtc tick\n"); return -ENOENT; } s3c_rtc_alarmno = platform_get_irq(pdev, 0); if (s3c_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", s3c_rtc_tickno, s3c_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; } s3c_rtc_mem = request_mem_region(res->start, res->end-res->start+1, pdev->name); if (s3c_rtc_mem == NULL) { dev_err(&pdev->dev, "failed to reserve memory region\n"); ret = -ENOENT; goto err_nores; } s3c_rtc_base = ioremap(res->start, res->end - res->start + 1); if (s3c_rtc_base == NULL) { dev_err(&pdev->dev, "failed ioremap()\n"); ret = -EINVAL; goto err_nomap; } /* check to see if everything is setup correctly */ s3c_rtc_enable(pdev, 1); pr_debug("s3c2410_rtc: RTCCON=%02x\n", readb(s3c_rtc_base + S3C2410_RTCCON)); s3c_rtc_setfreq(s3c_rtc_freq); /* register RTC and exit */ rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops, THIS_MODULE); if (IS_ERR(rtc)) { dev_err(&pdev->dev, "cannot attach rtc\n"); ret = PTR_ERR(rtc); goto err_nortc; } rtc->max_user_freq = 128; platform_set_drvdata(pdev, rtc); return 0; err_nortc: s3c_rtc_enable(pdev, 0); iounmap(s3c_rtc_base); err_nomap: release_resource(s3c_rtc_mem); err_nores: return ret; } #ifdef CONFIG_PM /* RTC Power management control */ static struct timespec s3c_rtc_delta; static int ticnt_save; static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state) { /* save TICNT for anyone using periodic interrupts */ ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT); s3c_rtc_enable(pdev, 0); return 0; } static int s3c_rtc_resume(struct platform_device *pdev) { s3c_rtc_enable(pdev, 1); writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT); return 0; } #else #define s3c_rtc_suspend NULL #define s3c_rtc_resume NULL #endif static struct platform_driver s3c2410_rtcdrv = { .probe = s3c_rtc_probe, .remove = s3c_rtc_remove, .suspend = s3c_rtc_suspend, .resume = s3c_rtc_resume, .driver = { .name = "s3c2410-rtc", .owner = THIS_MODULE, }, }; static char __initdata banner[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n"; static int __init s3c_rtc_init(void) { printk(banner); return platform_driver_register(&s3c2410_rtcdrv); } static void __exit s3c_rtc_exit(void) { platform_driver_unregister(&s3c2410_rtcdrv); } module_init(s3c_rtc_init); module_exit(s3c_rtc_exit); MODULE_DESCRIPTION("Samsung S3C RTC Driver"); MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>"); MODULE_LICENSE("GPL");