diff options
Diffstat (limited to 'drivers/rtc/rtc-sh.c')
| -rw-r--r-- | drivers/rtc/rtc-sh.c | 644 |
1 files changed, 644 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-sh.c b/drivers/rtc/rtc-sh.c new file mode 100644 index 000000000000..72ba1a70f35f --- /dev/null +++ b/drivers/rtc/rtc-sh.c @@ -0,0 +1,644 @@ +/* + * 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->class_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->class_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->class_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, "alarm_IRQ\t: %s\n", + (tmp & RCR1_AIE) ? "yes" : "no"); + 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; + + 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 flag */ + rcr1 = readb(rtc->regbase + RCR1); + rcr1 &= ~RCR1_AF; + writeb(rcr1 & ~RCR1_AIE, 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); + + /* Restore interrupt activation status */ + 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"); |