drivers/rtc/rtc-pl031.c: enable clock on all ST variants
[linux-flexiantxendom0.git] / drivers / rtc / rtc-pl031.c
index 2fd49ed..e86edfc 100644 (file)
@@ -7,28 +7,23 @@
  *
  * Copyright 2006 (c) MontaVista Software, Inc.
  *
+ * Author: Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
+ * Copyright 2010 (c) ST-Ericsson AB
+ *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * as published by the Free Software Foundation; either version
  * 2 of the License, or (at your option) any later version.
  */
-
-#include <linux/platform_device.h>
 #include <linux/module.h>
 #include <linux/rtc.h>
 #include <linux/init.h>
-#include <linux/fs.h>
 #include <linux/interrupt.h>
-#include <linux/string.h>
-#include <linux/pm.h>
-#include <linux/bitops.h>
-
 #include <linux/amba/bus.h>
-
-#include <asm/io.h>
-#include <asm/hardware.h>
-#include <asm/irq.h>
-#include <asm/rtc.h>
+#include <linux/io.h>
+#include <linux/bcd.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
 
 /*
  * Register definitions
 #define        RTC_RIS         0x14    /* Raw interrupt status register */
 #define        RTC_MIS         0x18    /* Masked interrupt status register */
 #define        RTC_ICR         0x1c    /* Interrupt clear register */
+/* ST variants have additional timer functionality */
+#define RTC_TDR                0x20    /* Timer data read register */
+#define RTC_TLR                0x24    /* Timer data load register */
+#define RTC_TCR                0x28    /* Timer control register */
+#define RTC_YDR                0x30    /* Year data read register */
+#define RTC_YMR                0x34    /* Year match register */
+#define RTC_YLR                0x38    /* Year data load register */
+
+#define RTC_CR_CWEN    (1 << 26)       /* Clockwatch enable bit */
+
+#define RTC_TCR_EN     (1 << 1) /* Periodic timer enable bit */
+
+/* Common bit definitions for Interrupt status and control registers */
+#define RTC_BIT_AI     (1 << 0) /* Alarm interrupt bit */
+#define RTC_BIT_PI     (1 << 1) /* Periodic interrupt bit. ST variants only. */
+
+/* Common bit definations for ST v2 for reading/writing time */
+#define RTC_SEC_SHIFT 0
+#define RTC_SEC_MASK (0x3F << RTC_SEC_SHIFT) /* Second [0-59] */
+#define RTC_MIN_SHIFT 6
+#define RTC_MIN_MASK (0x3F << RTC_MIN_SHIFT) /* Minute [0-59] */
+#define RTC_HOUR_SHIFT 12
+#define RTC_HOUR_MASK (0x1F << RTC_HOUR_SHIFT) /* Hour [0-23] */
+#define RTC_WDAY_SHIFT 17
+#define RTC_WDAY_MASK (0x7 << RTC_WDAY_SHIFT) /* Day of Week [1-7] 1=Sunday */
+#define RTC_MDAY_SHIFT 20
+#define RTC_MDAY_MASK (0x1F << RTC_MDAY_SHIFT) /* Day of Month [1-31] */
+#define RTC_MON_SHIFT 25
+#define RTC_MON_MASK (0xF << RTC_MON_SHIFT) /* Month [1-12] 1=January */
+
+#define RTC_TIMER_FREQ 32768
 
 struct pl031_local {
        struct rtc_device *rtc;
        void __iomem *base;
+       u8 hw_designer;
+       u8 hw_revision:4;
 };
 
-static irqreturn_t pl031_interrupt(int irq, void *dev_id)
+static int pl031_alarm_irq_enable(struct device *dev,
+       unsigned int enabled)
 {
-       struct rtc_device *rtc = dev_id;
+       struct pl031_local *ldata = dev_get_drvdata(dev);
+       unsigned long imsc;
+
+       /* Clear any pending alarm interrupts. */
+       writel(RTC_BIT_AI, ldata->base + RTC_ICR);
+
+       imsc = readl(ldata->base + RTC_IMSC);
 
-       rtc_update_irq(rtc, 1, RTC_AF);
+       if (enabled == 1)
+               writel(imsc | RTC_BIT_AI, ldata->base + RTC_IMSC);
+       else
+               writel(imsc & ~RTC_BIT_AI, ldata->base + RTC_IMSC);
 
-       return IRQ_HANDLED;
+       return 0;
 }
 
-static int pl031_open(struct device *dev)
+/*
+ * Convert Gregorian date to ST v2 RTC format.
+ */
+static int pl031_stv2_tm_to_time(struct device *dev,
+                                struct rtc_time *tm, unsigned long *st_time,
+       unsigned long *bcd_year)
 {
-       /*
-        * We request IRQ in pl031_probe, so nothing to do here...
-        */
+       int year = tm->tm_year + 1900;
+       int wday = tm->tm_wday;
+
+       /* wday masking is not working in hardware so wday must be valid */
+       if (wday < -1 || wday > 6) {
+               dev_err(dev, "invalid wday value %d\n", tm->tm_wday);
+               return -EINVAL;
+       } else if (wday == -1) {
+               /* wday is not provided, calculate it here */
+               unsigned long time;
+               struct rtc_time calc_tm;
+
+               rtc_tm_to_time(tm, &time);
+               rtc_time_to_tm(time, &calc_tm);
+               wday = calc_tm.tm_wday;
+       }
+
+       *bcd_year = (bin2bcd(year % 100) | bin2bcd(year / 100) << 8);
+
+       *st_time = ((tm->tm_mon + 1) << RTC_MON_SHIFT)
+                       |       (tm->tm_mday << RTC_MDAY_SHIFT)
+                       |       ((wday + 1) << RTC_WDAY_SHIFT)
+                       |       (tm->tm_hour << RTC_HOUR_SHIFT)
+                       |       (tm->tm_min << RTC_MIN_SHIFT)
+                       |       (tm->tm_sec << RTC_SEC_SHIFT);
+
        return 0;
 }
 
-static void pl031_release(struct device *dev)
+/*
+ * Convert ST v2 RTC format to Gregorian date.
+ */
+static int pl031_stv2_time_to_tm(unsigned long st_time, unsigned long bcd_year,
+       struct rtc_time *tm)
+{
+       tm->tm_year = bcd2bin(bcd_year) + (bcd2bin(bcd_year >> 8) * 100);
+       tm->tm_mon  = ((st_time & RTC_MON_MASK) >> RTC_MON_SHIFT) - 1;
+       tm->tm_mday = ((st_time & RTC_MDAY_MASK) >> RTC_MDAY_SHIFT);
+       tm->tm_wday = ((st_time & RTC_WDAY_MASK) >> RTC_WDAY_SHIFT) - 1;
+       tm->tm_hour = ((st_time & RTC_HOUR_MASK) >> RTC_HOUR_SHIFT);
+       tm->tm_min  = ((st_time & RTC_MIN_MASK) >> RTC_MIN_SHIFT);
+       tm->tm_sec  = ((st_time & RTC_SEC_MASK) >> RTC_SEC_SHIFT);
+
+       tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
+       tm->tm_year -= 1900;
+
+       return 0;
+}
+
+static int pl031_stv2_read_time(struct device *dev, struct rtc_time *tm)
 {
+       struct pl031_local *ldata = dev_get_drvdata(dev);
+
+       pl031_stv2_time_to_tm(readl(ldata->base + RTC_DR),
+                       readl(ldata->base + RTC_YDR), tm);
+
+       return 0;
 }
 
-static int pl031_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
+static int pl031_stv2_set_time(struct device *dev, struct rtc_time *tm)
 {
+       unsigned long time;
+       unsigned long bcd_year;
        struct pl031_local *ldata = dev_get_drvdata(dev);
+       int ret;
+
+       ret = pl031_stv2_tm_to_time(dev, tm, &time, &bcd_year);
+       if (ret == 0) {
+               writel(bcd_year, ldata->base + RTC_YLR);
+               writel(time, ldata->base + RTC_LR);
+       }
+
+       return ret;
+}
+
+static int pl031_stv2_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+       struct pl031_local *ldata = dev_get_drvdata(dev);
+       int ret;
+
+       ret = pl031_stv2_time_to_tm(readl(ldata->base + RTC_MR),
+                       readl(ldata->base + RTC_YMR), &alarm->time);
+
+       alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
+       alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
+
+       return ret;
+}
+
+static int pl031_stv2_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+       struct pl031_local *ldata = dev_get_drvdata(dev);
+       unsigned long time;
+       unsigned long bcd_year;
+       int ret;
+
+       /* At the moment, we can only deal with non-wildcarded alarm times. */
+       ret = rtc_valid_tm(&alarm->time);
+       if (ret == 0) {
+               ret = pl031_stv2_tm_to_time(dev, &alarm->time,
+                                           &time, &bcd_year);
+               if (ret == 0) {
+                       writel(bcd_year, ldata->base + RTC_YMR);
+                       writel(time, ldata->base + RTC_MR);
+
+                       pl031_alarm_irq_enable(dev, alarm->enabled);
+               }
+       }
+
+       return ret;
+}
+
+static irqreturn_t pl031_interrupt(int irq, void *dev_id)
+{
+       struct pl031_local *ldata = dev_id;
+       unsigned long rtcmis;
+       unsigned long events = 0;
+
+       rtcmis = readl(ldata->base + RTC_MIS);
+       if (rtcmis) {
+               writel(rtcmis, ldata->base + RTC_ICR);
 
-       switch (cmd) {
-       case RTC_AIE_OFF:
-               __raw_writel(1, ldata->base + RTC_MIS);
-               return 0;
-       case RTC_AIE_ON:
-               __raw_writel(0, ldata->base + RTC_MIS);
-               return 0;
+               if (rtcmis & RTC_BIT_AI)
+                       events |= (RTC_AF | RTC_IRQF);
+
+               /* Timer interrupt is only available in ST variants */
+               if ((rtcmis & RTC_BIT_PI) &&
+                       (ldata->hw_designer == AMBA_VENDOR_ST))
+                       events |= (RTC_PF | RTC_IRQF);
+
+               rtc_update_irq(ldata->rtc, 1, events);
+
+               return IRQ_HANDLED;
        }
 
-       return -ENOIOCTLCMD;
+       return IRQ_NONE;
 }
 
 static int pl031_read_time(struct device *dev, struct rtc_time *tm)
 {
        struct pl031_local *ldata = dev_get_drvdata(dev);
 
-       rtc_time_to_tm(__raw_readl(ldata->base + RTC_DR), tm);
+       rtc_time_to_tm(readl(ldata->base + RTC_DR), tm);
 
        return 0;
 }
@@ -97,20 +252,24 @@ static int pl031_set_time(struct device *dev, struct rtc_time *tm)
 {
        unsigned long time;
        struct pl031_local *ldata = dev_get_drvdata(dev);
+       int ret;
 
-       rtc_tm_to_time(tm, &time);
-       __raw_writel(time, ldata->base + RTC_LR);
+       ret = rtc_tm_to_time(tm, &time);
 
-       return 0;
+       if (ret == 0)
+               writel(time, ldata->base + RTC_LR);
+
+       return ret;
 }
 
 static int pl031_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 {
        struct pl031_local *ldata = dev_get_drvdata(dev);
 
-       rtc_time_to_tm(__raw_readl(ldata->base + RTC_MR), &alarm->time);
-       alarm->pending = __raw_readl(ldata->base + RTC_RIS);
-       alarm->enabled = __raw_readl(ldata->base + RTC_IMSC);
+       rtc_time_to_tm(readl(ldata->base + RTC_MR), &alarm->time);
+
+       alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
+       alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
 
        return 0;
 }
@@ -119,90 +278,144 @@ static int pl031_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 {
        struct pl031_local *ldata = dev_get_drvdata(dev);
        unsigned long time;
+       int ret;
 
-       rtc_tm_to_time(&alarm->time, &time);
-
-       __raw_writel(time, ldata->base + RTC_MR);
-       __raw_writel(!alarm->enabled, ldata->base + RTC_MIS);
+       /* At the moment, we can only deal with non-wildcarded alarm times. */
+       ret = rtc_valid_tm(&alarm->time);
+       if (ret == 0) {
+               ret = rtc_tm_to_time(&alarm->time, &time);
+               if (ret == 0) {
+                       writel(time, ldata->base + RTC_MR);
+                       pl031_alarm_irq_enable(dev, alarm->enabled);
+               }
+       }
 
-       return 0;
+       return ret;
 }
 
-static const struct rtc_class_ops pl031_ops = {
-       .open = pl031_open,
-       .release = pl031_release,
-       .ioctl = pl031_ioctl,
-       .read_time = pl031_read_time,
-       .set_time = pl031_set_time,
-       .read_alarm = pl031_read_alarm,
-       .set_alarm = pl031_set_alarm,
-};
-
 static int pl031_remove(struct amba_device *adev)
 {
        struct pl031_local *ldata = dev_get_drvdata(&adev->dev);
 
-       if (ldata) {
-               dev_set_drvdata(&adev->dev, NULL);
-               free_irq(adev->irq[0], ldata->rtc);
-               rtc_device_unregister(ldata->rtc);
-               iounmap(ldata->base);
-               kfree(ldata);
-       }
+       amba_set_drvdata(adev, NULL);
+       free_irq(adev->irq[0], ldata->rtc);
+       rtc_device_unregister(ldata->rtc);
+       iounmap(ldata->base);
+       kfree(ldata);
+       amba_release_regions(adev);
 
        return 0;
 }
 
-static int pl031_probe(struct amba_device *adev, void *id)
+static int pl031_probe(struct amba_device *adev, const struct amba_id *id)
 {
        int ret;
        struct pl031_local *ldata;
+       struct rtc_class_ops *ops = id->data;
 
+       ret = amba_request_regions(adev, NULL);
+       if (ret)
+               goto err_req;
 
-       ldata = kmalloc(sizeof(struct pl031_local), GFP_KERNEL);
+       ldata = kzalloc(sizeof(struct pl031_local), GFP_KERNEL);
        if (!ldata) {
                ret = -ENOMEM;
                goto out;
        }
-       dev_set_drvdata(&adev->dev, ldata);
 
-       ldata->base = ioremap(adev->res.start,
-                             adev->res.end - adev->res.start + 1);
+       ldata->base = ioremap(adev->res.start, resource_size(&adev->res));
+
        if (!ldata->base) {
                ret = -ENOMEM;
                goto out_no_remap;
        }
 
-       if (request_irq(adev->irq[0], pl031_interrupt, IRQF_DISABLED,
-                       "rtc-pl031", ldata->rtc)) {
-               ret = -EIO;
-               goto out_no_irq;
-       }
+       amba_set_drvdata(adev, ldata);
+
+       ldata->hw_designer = amba_manf(adev);
+       ldata->hw_revision = amba_rev(adev);
+
+       dev_dbg(&adev->dev, "designer ID = 0x%02x\n", ldata->hw_designer);
+       dev_dbg(&adev->dev, "revision = 0x%01x\n", ldata->hw_revision);
 
-       ldata->rtc = rtc_device_register("pl031", &adev->dev, &pl031_ops,
-                                        THIS_MODULE);
+       /* Enable the clockwatch on ST Variants */
+       if (ldata->hw_designer == AMBA_VENDOR_ST)
+               writel(readl(ldata->base + RTC_CR) | RTC_CR_CWEN,
+                      ldata->base + RTC_CR);
+
+       ldata->rtc = rtc_device_register("pl031", &adev->dev, ops,
+                                       THIS_MODULE);
        if (IS_ERR(ldata->rtc)) {
                ret = PTR_ERR(ldata->rtc);
                goto out_no_rtc;
        }
 
+       if (request_irq(adev->irq[0], pl031_interrupt,
+                       IRQF_DISABLED, "rtc-pl031", ldata)) {
+               ret = -EIO;
+               goto out_no_irq;
+       }
+
        return 0;
 
-out_no_rtc:
-       free_irq(adev->irq[0], ldata->rtc);
 out_no_irq:
+       rtc_device_unregister(ldata->rtc);
+out_no_rtc:
        iounmap(ldata->base);
+       amba_set_drvdata(adev, NULL);
 out_no_remap:
-       dev_set_drvdata(&adev->dev, NULL);
        kfree(ldata);
 out:
+       amba_release_regions(adev);
+err_req:
+
        return ret;
 }
 
-static struct amba_id pl031_ids[] __initdata = {
+/* Operations for the original ARM version */
+static struct rtc_class_ops arm_pl031_ops = {
+       .read_time = pl031_read_time,
+       .set_time = pl031_set_time,
+       .read_alarm = pl031_read_alarm,
+       .set_alarm = pl031_set_alarm,
+       .alarm_irq_enable = pl031_alarm_irq_enable,
+};
+
+/* The First ST derivative */
+static struct rtc_class_ops stv1_pl031_ops = {
+       .read_time = pl031_read_time,
+       .set_time = pl031_set_time,
+       .read_alarm = pl031_read_alarm,
+       .set_alarm = pl031_set_alarm,
+       .alarm_irq_enable = pl031_alarm_irq_enable,
+};
+
+/* And the second ST derivative */
+static struct rtc_class_ops stv2_pl031_ops = {
+       .read_time = pl031_stv2_read_time,
+       .set_time = pl031_stv2_set_time,
+       .read_alarm = pl031_stv2_read_alarm,
+       .set_alarm = pl031_stv2_set_alarm,
+       .alarm_irq_enable = pl031_alarm_irq_enable,
+};
+
+static struct amba_id pl031_ids[] = {
+       {
+               .id = 0x00041031,
+               .mask = 0x000fffff,
+               .data = &arm_pl031_ops,
+       },
+       /* ST Micro variants */
        {
-                .id = 0x00041031,
-               .mask = 0x000fffff, },
+               .id = 0x00180031,
+               .mask = 0x00ffffff,
+               .data = &stv1_pl031_ops,
+       },
+       {
+               .id = 0x00280031,
+               .mask = 0x00ffffff,
+               .data = &stv2_pl031_ops,
+       },
        {0, 0},
 };