--- /dev/null
+/*
+ * SuperH On-Chip RTC Support
+ *
+ * Copyright (C) 2006 Paul Mundt
+ *
+ * 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 <asm/io.h>
+
+#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)
+#define RMINCNT RTC_REG(2)
+#define RHRCNT RTC_REG(3)
+#define RWKCNT RTC_REG(4)
+#define RDAYCNT RTC_REG(5)
+#define RMONCNT RTC_REG(6)
+#define RYRCNT RTC_REG(7)
+#define RSECAR RTC_REG(8)
+#define RMINAR RTC_REG(9)
+#define RHRAR RTC_REG(10)
+#define RWKAR RTC_REG(11)
+#define RDAYAR RTC_REG(12)
+#define RMONAR RTC_REG(13)
+#define RCR1 RTC_REG(14)
+#define RCR2 RTC_REG(15)
+
+/* 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;
+};
+
+static irqreturn_t sh_rtc_interrupt(int irq, void *id, struct pt_regs *regs)
+{
+ struct platform_device *pdev = id;
+ struct sh_rtc *rtc = platform_get_drvdata(pdev);
+ unsigned int tmp, events = 0;
+
+ spin_lock(&rtc->lock);
+
+ tmp = readb(rtc->regbase + RCR1);
+
+ if (tmp & RCR1_AF)
+ events |= RTC_AF | RTC_IRQF;
+
+ tmp &= ~(RCR1_CF | RCR1_AF);
+
+ 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_periodic(int irq, void *id, struct pt_regs *regs)
+{
+ struct sh_rtc *rtc = dev_get_drvdata(id);
+
+ 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;
+ else
+ 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, SA_INTERRUPT,
+ "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, SA_INTERRUPT,
+ "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_interrupt, SA_INTERRUPT,
+ "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);
+
+ 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));
+
+#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, 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), 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 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,
+ .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 = "sh-rtc",
+ .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_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
+MODULE_LICENSE("GPL");