rtc-mv: add support for Alarm

This patch adds the Alarm support, this mode enabled when adding
IORESOURCE_IRQ to the platform device resources.

The patch also enables the wakeup mode, so the wakealarm sysfs file (under
/sys/class/rtc/rtcX/) can be used to configure the alarm clock.

Signed-off-by: Saeed Bishara <saeed@marvell.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/rtc/rtc-mv.c b/drivers/rtc/rtc-mv.c
index e0263d2..dc052ce 100644 (file)
--- a/drivers/rtc/rtc-mv.c
+++ b/drivers/rtc/rtc-mv.c
@@ -27,10 +27,17 @@
 #define RTC_MONTH_OFFS         8
 #define RTC_YEAR_OFFS          16
 
+#define RTC_ALARM_TIME_REG_OFFS        8
+#define RTC_ALARM_DATE_REG_OFFS        0xc
+#define RTC_ALARM_VALID                (1 << 7)
+
+#define RTC_ALARM_INTERRUPT_MASK_REG_OFFS      0x10
+#define RTC_ALARM_INTERRUPT_CASUE_REG_OFFS     0x14
 
 struct rtc_plat_data {
        struct rtc_device *rtc;
        void __iomem *ioaddr;
+       int             irq;
 };
 
 static int mv_rtc_set_time(struct device *dev, struct rtc_time *tm)
@@ -84,12 +91,134 @@ static int mv_rtc_read_time(struct device *dev, struct rtc_time *tm)
        return rtc_valid_tm(tm);
 }
 
+static int mv_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+       struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+       void __iomem *ioaddr = pdata->ioaddr;
+       u32     rtc_time, rtc_date;
+       unsigned int year, month, day, hour, minute, second, wday;
+
+       rtc_time = readl(ioaddr + RTC_ALARM_TIME_REG_OFFS);
+       rtc_date = readl(ioaddr + RTC_ALARM_DATE_REG_OFFS);
+
+       second = rtc_time & 0x7f;
+       minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f;
+       hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */
+       wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7;
+
+       day = rtc_date & 0x3f;
+       month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f;
+       year = (rtc_date >> RTC_YEAR_OFFS) & 0xff;
+
+       alm->time.tm_sec = bcd2bin(second);
+       alm->time.tm_min = bcd2bin(minute);
+       alm->time.tm_hour = bcd2bin(hour);
+       alm->time.tm_mday = bcd2bin(day);
+       alm->time.tm_wday = bcd2bin(wday);
+       alm->time.tm_mon = bcd2bin(month) - 1;
+       /* hw counts from year 2000, but tm_year is relative to 1900 */
+       alm->time.tm_year = bcd2bin(year) + 100;
+
+       if (rtc_valid_tm(&alm->time) < 0) {
+               dev_err(dev, "retrieved alarm date/time is not valid.\n");
+               rtc_time_to_tm(0, &alm->time);
+       }
+
+       alm->enabled = !!readl(ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS);
+       return 0;
+}
+
+static int mv_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+       struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+       void __iomem *ioaddr = pdata->ioaddr;
+       u32 rtc_reg = 0;
+
+       if (alm->time.tm_sec >= 0)
+               rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_sec))
+                       << RTC_SECONDS_OFFS;
+       if (alm->time.tm_min >= 0)
+               rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_min))
+                       << RTC_MINUTES_OFFS;
+       if (alm->time.tm_hour >= 0)
+               rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_hour))
+                       << RTC_HOURS_OFFS;
+
+       writel(rtc_reg, ioaddr + RTC_ALARM_TIME_REG_OFFS);
+
+       if (alm->time.tm_mday >= 0)
+               rtc_reg = (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mday))
+                       << RTC_MDAY_OFFS;
+       else
+               rtc_reg = 0;
+
+       if (alm->time.tm_mon >= 0)
+               rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mon + 1))
+                       << RTC_MONTH_OFFS;
+
+       if (alm->time.tm_year >= 0)
+               rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_year % 100))
+                       << RTC_YEAR_OFFS;
+
+       writel(rtc_reg, ioaddr + RTC_ALARM_DATE_REG_OFFS);
+       writel(0, ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS);
+       writel(alm->enabled ? 1 : 0,
+              ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS);
+
+       return 0;
+}
+
+static int mv_rtc_ioctl(struct device *dev, unsigned int cmd,
+                       unsigned long arg)
+{
+       struct platform_device *pdev = to_platform_device(dev);
+       struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
+       void __iomem *ioaddr = pdata->ioaddr;
+
+       if (pdata->irq < 0)
+               return -ENOIOCTLCMD; /* fall back into rtc-dev's emulation */
+       switch (cmd) {
+       case RTC_AIE_OFF:
+               writel(0, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS);
+               break;
+       case RTC_AIE_ON:
+               writel(1, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS);
+               break;
+       default:
+               return -ENOIOCTLCMD;
+       }
+       return 0;
+}
+
+static irqreturn_t mv_rtc_interrupt(int irq, void *data)
+{
+       struct rtc_plat_data *pdata = data;
+       void __iomem *ioaddr = pdata->ioaddr;
+
+       /* alarm irq? */
+       if (!readl(ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS))
+               return IRQ_NONE;
+
+       /* clear interrupt */
+       writel(0, ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS);
+       rtc_update_irq(pdata->rtc, 1, RTC_IRQF | RTC_AF);
+       return IRQ_HANDLED;
+}
+
 static const struct rtc_class_ops mv_rtc_ops = {
        .read_time      = mv_rtc_read_time,
        .set_time       = mv_rtc_set_time,
 };
 
-static int __init mv_rtc_probe(struct platform_device *pdev)
+static const struct rtc_class_ops mv_rtc_alarm_ops = {
+       .read_time      = mv_rtc_read_time,
+       .set_time       = mv_rtc_set_time,
+       .read_alarm     = mv_rtc_read_alarm,
+       .set_alarm      = mv_rtc_set_alarm,
+       .ioctl          = mv_rtc_ioctl,
+};
+
+static int __devinit mv_rtc_probe(struct platform_device *pdev)
 {
        struct resource *res;
        struct rtc_plat_data *pdata;
@@ -130,12 +259,31 @@ static int __init mv_rtc_probe(struct platform_device *pdev)
                }
        }
 
+       pdata->irq = platform_get_irq(pdev, 0);
+
        platform_set_drvdata(pdev, pdata);
-       pdata->rtc = rtc_device_register(pdev->name, &pdev->dev,
-                                        &mv_rtc_ops, THIS_MODULE);
+
+       if (pdata->irq >= 0) {
+               device_init_wakeup(&pdev->dev, 1);
+               pdata->rtc = rtc_device_register(pdev->name, &pdev->dev,
+                                                &mv_rtc_alarm_ops,
+                                                THIS_MODULE);
+       } else
+               pdata->rtc = rtc_device_register(pdev->name, &pdev->dev,
+                                                &mv_rtc_ops, THIS_MODULE);
        if (IS_ERR(pdata->rtc))
                return PTR_ERR(pdata->rtc);
 
+       if (pdata->irq >= 0) {
+               writel(0, pdata->ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS);
+               if (devm_request_irq(&pdev->dev, pdata->irq, mv_rtc_interrupt,
+                                    IRQF_DISABLED | IRQF_SHARED,
+                                    pdev->name, pdata) < 0) {
+                       dev_warn(&pdev->dev, "interrupt not available.\n");
+                       pdata->irq = -1;
+               }
+       }
+
        return 0;
 }
 
@@ -143,6 +291,9 @@ static int __exit mv_rtc_remove(struct platform_device *pdev)
 {
        struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
 
+       if (pdata->irq >= 0)
+               device_init_wakeup(&pdev->dev, 0);
+
        rtc_device_unregister(pdata->rtc);
        return 0;
 }