/* * SuperH On-Chip RTC Support * * Copyright (C) 2006 Paul Mundt * Copyright (C) 2006 Jamie Lenehan * * Based on the old arch/sh/kernel/cpu/rtc.c by: * * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org> * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. */ #include <linux/module.h> #include <linux/kernel.h> #include <linux/bcd.h> #include <linux/rtc.h> #include <linux/init.h> #include <linux/platform_device.h> #include <linux/seq_file.h> #include <linux/interrupt.h> #include <linux/spinlock.h> #include <linux/io.h> #define DRV_NAME "sh-rtc" #define DRV_VERSION "0.1.2" #ifdef CONFIG_CPU_SH3 #define rtc_reg_size sizeof(u16) #define RTC_BIT_INVERTED 0 /* No bug on SH7708, SH7709A */ #elif defined(CONFIG_CPU_SH4) #define rtc_reg_size sizeof(u32) #define RTC_BIT_INVERTED 0x40 /* bug on SH7750, SH7750S */ #endif #define RTC_REG(r) ((r) * rtc_reg_size) #define R64CNT RTC_REG(0) #define RSECCNT RTC_REG(1) /* RTC sec */ #define RMINCNT RTC_REG(2) /* RTC min */ #define RHRCNT RTC_REG(3) /* RTC hour */ #define RWKCNT RTC_REG(4) /* RTC week */ #define RDAYCNT RTC_REG(5) /* RTC day */ #define RMONCNT RTC_REG(6) /* RTC month */ #define RYRCNT RTC_REG(7) /* RTC year */ #define RSECAR RTC_REG(8) /* ALARM sec */ #define RMINAR RTC_REG(9) /* ALARM min */ #define RHRAR RTC_REG(10) /* ALARM hour */ #define RWKAR RTC_REG(11) /* ALARM week */ #define RDAYAR RTC_REG(12) /* ALARM day */ #define RMONAR RTC_REG(13) /* ALARM month */ #define RCR1 RTC_REG(14) /* Control */ #define RCR2 RTC_REG(15) /* Control */ /* ALARM Bits - or with BCD encoded value */ #define AR_ENB 0x80 /* Enable for alarm cmp */ /* RCR1 Bits */ #define RCR1_CF 0x80 /* Carry Flag */ #define RCR1_CIE 0x10 /* Carry Interrupt Enable */ #define RCR1_AIE 0x08 /* Alarm Interrupt Enable */ #define RCR1_AF 0x01 /* Alarm Flag */ /* RCR2 Bits */ #define RCR2_PEF 0x80 /* PEriodic interrupt Flag */ #define RCR2_PESMASK 0x70 /* Periodic interrupt Set */ #define RCR2_RTCEN 0x08 /* ENable RTC */ #define RCR2_ADJ 0x04 /* ADJustment (30-second) */ #define RCR2_RESET 0x02 /* Reset bit */ #define RCR2_START 0x01 /* Start bit */ struct sh_rtc { void __iomem *regbase; unsigned long regsize; struct resource *res; unsigned int alarm_irq, periodic_irq, carry_irq; struct rtc_device *rtc_dev; spinlock_t lock; int rearm_aie; }; static irqreturn_t sh_rtc_interrupt(int irq, void *dev_id) { struct platform_device *pdev = to_platform_device(dev_id); struct sh_rtc *rtc = platform_get_drvdata(pdev); unsigned int tmp, events = 0; spin_lock(&rtc->lock); tmp = readb(rtc->regbase + RCR1); tmp &= ~RCR1_CF; if (rtc->rearm_aie) { if (tmp & RCR1_AF) tmp &= ~RCR1_AF; /* try to clear AF again */ else { tmp |= RCR1_AIE; /* AF has cleared, rearm IRQ */ rtc->rearm_aie = 0; } } writeb(tmp, rtc->regbase + RCR1); rtc_update_irq(rtc->rtc_dev, 1, events); spin_unlock(&rtc->lock); return IRQ_HANDLED; } static irqreturn_t sh_rtc_alarm(int irq, void *dev_id) { struct platform_device *pdev = to_platform_device(dev_id); struct sh_rtc *rtc = platform_get_drvdata(pdev); unsigned int tmp, events = 0; spin_lock(&rtc->lock); tmp = readb(rtc->regbase + RCR1); /* * If AF is set then the alarm has triggered. If we clear AF while * the alarm time still matches the RTC time then AF will * immediately be set again, and if AIE is enabled then the alarm * interrupt will immediately be retrigger. So we clear AIE here * and use rtc->rearm_aie so that the carry interrupt will keep * trying to clear AF and once it stays cleared it'll re-enable * AIE. */ if (tmp & RCR1_AF) { events |= RTC_AF | RTC_IRQF; tmp &= ~(RCR1_AF|RCR1_AIE); writeb(tmp, rtc->regbase + RCR1); rtc->rearm_aie = 1; rtc_update_irq(rtc->rtc_dev, 1, events); } spin_unlock(&rtc->lock); return IRQ_HANDLED; } static irqreturn_t sh_rtc_periodic(int irq, void *dev_id) { struct platform_device *pdev = to_platform_device(dev_id); struct sh_rtc *rtc = platform_get_drvdata(pdev); spin_lock(&rtc->lock); rtc_update_irq(rtc->rtc_dev, 1, RTC_PF | RTC_IRQF); spin_unlock(&rtc->lock); return IRQ_HANDLED; } static inline void sh_rtc_setpie(struct device *dev, unsigned int enable) { struct sh_rtc *rtc = dev_get_drvdata(dev); unsigned int tmp; spin_lock_irq(&rtc->lock); tmp = readb(rtc->regbase + RCR2); if (enable) { tmp &= ~RCR2_PESMASK; tmp |= RCR2_PEF | (2 << 4); } else tmp &= ~(RCR2_PESMASK | RCR2_PEF); writeb(tmp, rtc->regbase + RCR2); spin_unlock_irq(&rtc->lock); } static inline void sh_rtc_setaie(struct device *dev, unsigned int enable) { struct sh_rtc *rtc = dev_get_drvdata(dev); unsigned int tmp; spin_lock_irq(&rtc->lock); tmp = readb(rtc->regbase + RCR1); if (!enable) { tmp &= ~RCR1_AIE; rtc->rearm_aie = 0; } else if (rtc->rearm_aie == 0) tmp |= RCR1_AIE; writeb(tmp, rtc->regbase + RCR1); spin_unlock_irq(&rtc->lock); } static int sh_rtc_open(struct device *dev) { struct sh_rtc *rtc = dev_get_drvdata(dev); unsigned int tmp; int ret; tmp = readb(rtc->regbase + RCR1); tmp &= ~RCR1_CF; tmp |= RCR1_CIE; writeb(tmp, rtc->regbase + RCR1); ret = request_irq(rtc->periodic_irq, sh_rtc_periodic, IRQF_DISABLED, "sh-rtc period", dev); if (unlikely(ret)) { dev_err(dev, "request period IRQ failed with %d, IRQ %d\n", ret, rtc->periodic_irq); return ret; } ret = request_irq(rtc->carry_irq, sh_rtc_interrupt, IRQF_DISABLED, "sh-rtc carry", dev); if (unlikely(ret)) { dev_err(dev, "request carry IRQ failed with %d, IRQ %d\n", ret, rtc->carry_irq); free_irq(rtc->periodic_irq, dev); goto err_bad_carry; } ret = request_irq(rtc->alarm_irq, sh_rtc_alarm, IRQF_DISABLED, "sh-rtc alarm", dev); if (unlikely(ret)) { dev_err(dev, "request alarm IRQ failed with %d, IRQ %d\n", ret, rtc->alarm_irq); goto err_bad_alarm; } return 0; err_bad_alarm: free_irq(rtc->carry_irq, dev); err_bad_carry: free_irq(rtc->periodic_irq, dev); return ret; } static void sh_rtc_release(struct device *dev) { struct sh_rtc *rtc = dev_get_drvdata(dev); sh_rtc_setpie(dev, 0); sh_rtc_setaie(dev, 0); free_irq(rtc->periodic_irq, dev); free_irq(rtc->carry_irq, dev); free_irq(rtc->alarm_irq, dev); } static int sh_rtc_proc(struct device *dev, struct seq_file *seq) { struct sh_rtc *rtc = dev_get_drvdata(dev); unsigned int tmp; tmp = readb(rtc->regbase + RCR1); seq_printf(seq, "carry_IRQ\t: %s\n", (tmp & RCR1_CIE) ? "yes" : "no"); tmp = readb(rtc->regbase + RCR2); seq_printf(seq, "periodic_IRQ\t: %s\n", (tmp & RCR2_PEF) ? "yes" : "no"); return 0; } static int sh_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) { unsigned int ret = -ENOIOCTLCMD; switch (cmd) { case RTC_PIE_OFF: case RTC_PIE_ON: sh_rtc_setpie(dev, cmd == RTC_PIE_ON); ret = 0; break; case RTC_AIE_OFF: case RTC_AIE_ON: sh_rtc_setaie(dev, cmd == RTC_AIE_ON); ret = 0; break; } return ret; } static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm) { struct platform_device *pdev = to_platform_device(dev); struct sh_rtc *rtc = platform_get_drvdata(pdev); unsigned int sec128, sec2, yr, yr100, cf_bit; do { unsigned int tmp; spin_lock_irq(&rtc->lock); tmp = readb(rtc->regbase + RCR1); tmp &= ~RCR1_CF; /* Clear CF-bit */ tmp |= RCR1_CIE; writeb(tmp, rtc->regbase + RCR1); sec128 = readb(rtc->regbase + R64CNT); tm->tm_sec = BCD2BIN(readb(rtc->regbase + RSECCNT)); tm->tm_min = BCD2BIN(readb(rtc->regbase + RMINCNT)); tm->tm_hour = BCD2BIN(readb(rtc->regbase + RHRCNT)); tm->tm_wday = BCD2BIN(readb(rtc->regbase + RWKCNT)); tm->tm_mday = BCD2BIN(readb(rtc->regbase + RDAYCNT)); tm->tm_mon = BCD2BIN(readb(rtc->regbase + RMONCNT)) - 1; #if defined(CONFIG_CPU_SH4) yr = readw(rtc->regbase + RYRCNT); yr100 = BCD2BIN(yr >> 8); yr &= 0xff; #else yr = readb(rtc->regbase + RYRCNT); yr100 = BCD2BIN((yr == 0x99) ? 0x19 : 0x20); #endif tm->tm_year = (yr100 * 100 + BCD2BIN(yr)) - 1900; sec2 = readb(rtc->regbase + R64CNT); cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF; spin_unlock_irq(&rtc->lock); } while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0); #if RTC_BIT_INVERTED != 0 if ((sec128 & RTC_BIT_INVERTED)) tm->tm_sec--; #endif dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, " "mday=%d, mon=%d, year=%d, wday=%d\n", __FUNCTION__, tm->tm_sec, tm->tm_min, tm->tm_hour, tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday); if (rtc_valid_tm(tm) < 0) dev_err(dev, "invalid date\n"); return 0; } static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm) { struct platform_device *pdev = to_platform_device(dev); struct sh_rtc *rtc = platform_get_drvdata(pdev); unsigned int tmp; int year; spin_lock_irq(&rtc->lock); /* Reset pre-scaler & stop RTC */ tmp = readb(rtc->regbase + RCR2); tmp |= RCR2_RESET; writeb(tmp, rtc->regbase + RCR2); writeb(BIN2BCD(tm->tm_sec), rtc->regbase + RSECCNT); writeb(BIN2BCD(tm->tm_min), rtc->regbase + RMINCNT); writeb(BIN2BCD(tm->tm_hour), rtc->regbase + RHRCNT); writeb(BIN2BCD(tm->tm_wday), rtc->regbase + RWKCNT); writeb(BIN2BCD(tm->tm_mday), rtc->regbase + RDAYCNT); writeb(BIN2BCD(tm->tm_mon + 1), rtc->regbase + RMONCNT); #ifdef CONFIG_CPU_SH3 year = tm->tm_year % 100; writeb(BIN2BCD(year), rtc->regbase + RYRCNT); #else year = (BIN2BCD((tm->tm_year + 1900) / 100) << 8) | BIN2BCD(tm->tm_year % 100); writew(year, rtc->regbase + RYRCNT); #endif /* Start RTC */ tmp = readb(rtc->regbase + RCR2); tmp &= ~RCR2_RESET; tmp |= RCR2_RTCEN | RCR2_START; writeb(tmp, rtc->regbase + RCR2); spin_unlock_irq(&rtc->lock); return 0; } static inline int sh_rtc_read_alarm_value(struct sh_rtc *rtc, int reg_off) { unsigned int byte; int value = 0xff; /* return 0xff for ignored values */ byte = readb(rtc->regbase + reg_off); if (byte & AR_ENB) { byte &= ~AR_ENB; /* strip the enable bit */ value = BCD2BIN(byte); } return value; } static int sh_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm) { struct platform_device *pdev = to_platform_device(dev); struct sh_rtc *rtc = platform_get_drvdata(pdev); struct rtc_time* tm = &wkalrm->time; spin_lock_irq(&rtc->lock); tm->tm_sec = sh_rtc_read_alarm_value(rtc, RSECAR); tm->tm_min = sh_rtc_read_alarm_value(rtc, RMINAR); tm->tm_hour = sh_rtc_read_alarm_value(rtc, RHRAR); tm->tm_wday = sh_rtc_read_alarm_value(rtc, RWKAR); tm->tm_mday = sh_rtc_read_alarm_value(rtc, RDAYAR); tm->tm_mon = sh_rtc_read_alarm_value(rtc, RMONAR); if (tm->tm_mon > 0) tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */ tm->tm_year = 0xffff; wkalrm->enabled = (readb(rtc->regbase + RCR1) & RCR1_AIE) ? 1 : 0; spin_unlock_irq(&rtc->lock); return 0; } static inline void sh_rtc_write_alarm_value(struct sh_rtc *rtc, int value, int reg_off) { /* < 0 for a value that is ignored */ if (value < 0) writeb(0, rtc->regbase + reg_off); else writeb(BIN2BCD(value) | AR_ENB, rtc->regbase + reg_off); } static int sh_rtc_check_alarm(struct rtc_time* tm) { /* * The original rtc says anything > 0xc0 is "don't care" or "match * all" - most users use 0xff but rtc-dev uses -1 for the same thing. * The original rtc doesn't support years - some things use -1 and * some 0xffff. We use -1 to make out tests easier. */ if (tm->tm_year == 0xffff) tm->tm_year = -1; if (tm->tm_mon >= 0xff) tm->tm_mon = -1; if (tm->tm_mday >= 0xff) tm->tm_mday = -1; if (tm->tm_wday >= 0xff) tm->tm_wday = -1; if (tm->tm_hour >= 0xff) tm->tm_hour = -1; if (tm->tm_min >= 0xff) tm->tm_min = -1; if (tm->tm_sec >= 0xff) tm->tm_sec = -1; if (tm->tm_year > 9999 || tm->tm_mon >= 12 || tm->tm_mday == 0 || tm->tm_mday >= 32 || tm->tm_wday >= 7 || tm->tm_hour >= 24 || tm->tm_min >= 60 || tm->tm_sec >= 60) return -EINVAL; return 0; } static int sh_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm) { struct platform_device *pdev = to_platform_device(dev); struct sh_rtc *rtc = platform_get_drvdata(pdev); unsigned int rcr1; struct rtc_time *tm = &wkalrm->time; int mon, err; err = sh_rtc_check_alarm(tm); if (unlikely(err < 0)) return err; spin_lock_irq(&rtc->lock); /* disable alarm interrupt and clear the alarm flag */ rcr1 = readb(rtc->regbase + RCR1); rcr1 &= ~(RCR1_AF|RCR1_AIE); writeb(rcr1, rtc->regbase + RCR1); rtc->rearm_aie = 0; /* set alarm time */ sh_rtc_write_alarm_value(rtc, tm->tm_sec, RSECAR); sh_rtc_write_alarm_value(rtc, tm->tm_min, RMINAR); sh_rtc_write_alarm_value(rtc, tm->tm_hour, RHRAR); sh_rtc_write_alarm_value(rtc, tm->tm_wday, RWKAR); sh_rtc_write_alarm_value(rtc, tm->tm_mday, RDAYAR); mon = tm->tm_mon; if (mon >= 0) mon += 1; sh_rtc_write_alarm_value(rtc, mon, RMONAR); if (wkalrm->enabled) { rcr1 |= RCR1_AIE; writeb(rcr1, rtc->regbase + RCR1); } spin_unlock_irq(&rtc->lock); return 0; } static struct rtc_class_ops sh_rtc_ops = { .open = sh_rtc_open, .release = sh_rtc_release, .ioctl = sh_rtc_ioctl, .read_time = sh_rtc_read_time, .set_time = sh_rtc_set_time, .read_alarm = sh_rtc_read_alarm, .set_alarm = sh_rtc_set_alarm, .proc = sh_rtc_proc, }; static int __devinit sh_rtc_probe(struct platform_device *pdev) { struct sh_rtc *rtc; struct resource *res; int ret = -ENOENT; rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL); if (unlikely(!rtc)) return -ENOMEM; spin_lock_init(&rtc->lock); rtc->periodic_irq = platform_get_irq(pdev, 0); if (unlikely(rtc->periodic_irq < 0)) { dev_err(&pdev->dev, "No IRQ for period\n"); goto err_badres; } rtc->carry_irq = platform_get_irq(pdev, 1); if (unlikely(rtc->carry_irq < 0)) { dev_err(&pdev->dev, "No IRQ for carry\n"); goto err_badres; } rtc->alarm_irq = platform_get_irq(pdev, 2); if (unlikely(rtc->alarm_irq < 0)) { dev_err(&pdev->dev, "No IRQ for alarm\n"); goto err_badres; } res = platform_get_resource(pdev, IORESOURCE_IO, 0); if (unlikely(res == NULL)) { dev_err(&pdev->dev, "No IO resource\n"); goto err_badres; } rtc->regsize = res->end - res->start + 1; rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name); if (unlikely(!rtc->res)) { ret = -EBUSY; goto err_badres; } rtc->regbase = (void __iomem *)rtc->res->start; if (unlikely(!rtc->regbase)) { ret = -EINVAL; goto err_badmap; } rtc->rtc_dev = rtc_device_register("sh", &pdev->dev, &sh_rtc_ops, THIS_MODULE); if (IS_ERR(rtc)) { ret = PTR_ERR(rtc->rtc_dev); goto err_badmap; } platform_set_drvdata(pdev, rtc); return 0; err_badmap: release_resource(rtc->res); err_badres: kfree(rtc); return ret; } static int __devexit sh_rtc_remove(struct platform_device *pdev) { struct sh_rtc *rtc = platform_get_drvdata(pdev); if (likely(rtc->rtc_dev)) rtc_device_unregister(rtc->rtc_dev); sh_rtc_setpie(&pdev->dev, 0); sh_rtc_setaie(&pdev->dev, 0); release_resource(rtc->res); platform_set_drvdata(pdev, NULL); kfree(rtc); return 0; } static struct platform_driver sh_rtc_platform_driver = { .driver = { .name = DRV_NAME, .owner = THIS_MODULE, }, .probe = sh_rtc_probe, .remove = __devexit_p(sh_rtc_remove), }; static int __init sh_rtc_init(void) { return platform_driver_register(&sh_rtc_platform_driver); } static void __exit sh_rtc_exit(void) { platform_driver_unregister(&sh_rtc_platform_driver); } module_init(sh_rtc_init); module_exit(sh_rtc_exit); MODULE_DESCRIPTION("SuperH on-chip RTC driver"); MODULE_VERSION(DRV_VERSION); MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, Jamie Lenehan <lenehan@twibble.org>"); MODULE_LICENSE("GPL");