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path: root/drivers/rtc/rtc-pxa.c
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-rw-r--r--drivers/rtc/rtc-pxa.c489
1 files changed, 489 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-pxa.c b/drivers/rtc/rtc-pxa.c
new file mode 100644
index 00000000000..cc7eb8767b8
--- /dev/null
+++ b/drivers/rtc/rtc-pxa.c
@@ -0,0 +1,489 @@
+/*
+ * Real Time Clock interface for XScale PXA27x and PXA3xx
+ *
+ * Copyright (C) 2008 Robert Jarzmik
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/rtc.h>
+#include <linux/seq_file.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+
+#define TIMER_FREQ CLOCK_TICK_RATE
+#define RTC_DEF_DIVIDER (32768 - 1)
+#define RTC_DEF_TRIM 0
+#define MAXFREQ_PERIODIC 1000
+
+/*
+ * PXA Registers and bits definitions
+ */
+#define RTSR_PICE (1 << 15) /* Periodic interrupt count enable */
+#define RTSR_PIALE (1 << 14) /* Periodic interrupt Alarm enable */
+#define RTSR_PIAL (1 << 13) /* Periodic interrupt detected */
+#define RTSR_SWALE2 (1 << 11) /* RTC stopwatch alarm2 enable */
+#define RTSR_SWAL2 (1 << 10) /* RTC stopwatch alarm2 detected */
+#define RTSR_SWALE1 (1 << 9) /* RTC stopwatch alarm1 enable */
+#define RTSR_SWAL1 (1 << 8) /* RTC stopwatch alarm1 detected */
+#define RTSR_RDALE2 (1 << 7) /* RTC alarm2 enable */
+#define RTSR_RDAL2 (1 << 6) /* RTC alarm2 detected */
+#define RTSR_RDALE1 (1 << 5) /* RTC alarm1 enable */
+#define RTSR_RDAL1 (1 << 4) /* RTC alarm1 detected */
+#define RTSR_HZE (1 << 3) /* HZ interrupt enable */
+#define RTSR_ALE (1 << 2) /* RTC alarm interrupt enable */
+#define RTSR_HZ (1 << 1) /* HZ rising-edge detected */
+#define RTSR_AL (1 << 0) /* RTC alarm detected */
+#define RTSR_TRIG_MASK (RTSR_AL | RTSR_HZ | RTSR_RDAL1 | RTSR_RDAL2\
+ | RTSR_SWAL1 | RTSR_SWAL2)
+#define RYxR_YEAR_S 9
+#define RYxR_YEAR_MASK (0xfff << RYxR_YEAR_S)
+#define RYxR_MONTH_S 5
+#define RYxR_MONTH_MASK (0xf << RYxR_MONTH_S)
+#define RYxR_DAY_MASK 0x1f
+#define RDxR_HOUR_S 12
+#define RDxR_HOUR_MASK (0x1f << RDxR_HOUR_S)
+#define RDxR_MIN_S 6
+#define RDxR_MIN_MASK (0x3f << RDxR_MIN_S)
+#define RDxR_SEC_MASK 0x3f
+
+#define RTSR 0x08
+#define RTTR 0x0c
+#define RDCR 0x10
+#define RYCR 0x14
+#define RDAR1 0x18
+#define RYAR1 0x1c
+#define RTCPICR 0x34
+#define PIAR 0x38
+
+#define rtc_readl(pxa_rtc, reg) \
+ __raw_readl((pxa_rtc)->base + (reg))
+#define rtc_writel(pxa_rtc, reg, value) \
+ __raw_writel((value), (pxa_rtc)->base + (reg))
+
+struct pxa_rtc {
+ struct resource *ress;
+ void __iomem *base;
+ int irq_1Hz;
+ int irq_Alrm;
+ struct rtc_device *rtc;
+ spinlock_t lock; /* Protects this structure */
+ struct rtc_time rtc_alarm;
+};
+
+static u32 ryxr_calc(struct rtc_time *tm)
+{
+ return ((tm->tm_year + 1900) << RYxR_YEAR_S)
+ | ((tm->tm_mon + 1) << RYxR_MONTH_S)
+ | tm->tm_mday;
+}
+
+static u32 rdxr_calc(struct rtc_time *tm)
+{
+ return (tm->tm_hour << RDxR_HOUR_S) | (tm->tm_min << RDxR_MIN_S)
+ | tm->tm_sec;
+}
+
+static void tm_calc(u32 rycr, u32 rdcr, struct rtc_time *tm)
+{
+ tm->tm_year = ((rycr & RYxR_YEAR_MASK) >> RYxR_YEAR_S) - 1900;
+ tm->tm_mon = (((rycr & RYxR_MONTH_MASK) >> RYxR_MONTH_S)) - 1;
+ tm->tm_mday = (rycr & RYxR_DAY_MASK);
+ tm->tm_hour = (rdcr & RDxR_HOUR_MASK) >> RDxR_HOUR_S;
+ tm->tm_min = (rdcr & RDxR_MIN_MASK) >> RDxR_MIN_S;
+ tm->tm_sec = rdcr & RDxR_SEC_MASK;
+}
+
+static void rtsr_clear_bits(struct pxa_rtc *pxa_rtc, u32 mask)
+{
+ u32 rtsr;
+
+ rtsr = rtc_readl(pxa_rtc, RTSR);
+ rtsr &= ~RTSR_TRIG_MASK;
+ rtsr &= ~mask;
+ rtc_writel(pxa_rtc, RTSR, rtsr);
+}
+
+static void rtsr_set_bits(struct pxa_rtc *pxa_rtc, u32 mask)
+{
+ u32 rtsr;
+
+ rtsr = rtc_readl(pxa_rtc, RTSR);
+ rtsr &= ~RTSR_TRIG_MASK;
+ rtsr |= mask;
+ rtc_writel(pxa_rtc, RTSR, rtsr);
+}
+
+static irqreturn_t pxa_rtc_irq(int irq, void *dev_id)
+{
+ struct platform_device *pdev = to_platform_device(dev_id);
+ struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);
+ u32 rtsr;
+ unsigned long events = 0;
+
+ spin_lock(&pxa_rtc->lock);
+
+ /* clear interrupt sources */
+ rtsr = rtc_readl(pxa_rtc, RTSR);
+ rtc_writel(pxa_rtc, RTSR, rtsr);
+
+ /* temporary disable rtc interrupts */
+ rtsr_clear_bits(pxa_rtc, RTSR_RDALE1 | RTSR_PIALE | RTSR_HZE);
+
+ /* clear alarm interrupt if it has occurred */
+ if (rtsr & RTSR_RDAL1)
+ rtsr &= ~RTSR_RDALE1;
+
+ /* update irq data & counter */
+ if (rtsr & RTSR_RDAL1)
+ events |= RTC_AF | RTC_IRQF;
+ if (rtsr & RTSR_HZ)
+ events |= RTC_UF | RTC_IRQF;
+ if (rtsr & RTSR_PIAL)
+ events |= RTC_PF | RTC_IRQF;
+
+ rtc_update_irq(pxa_rtc->rtc, 1, events);
+
+ /* enable back rtc interrupts */
+ rtc_writel(pxa_rtc, RTSR, rtsr & ~RTSR_TRIG_MASK);
+
+ spin_unlock(&pxa_rtc->lock);
+ return IRQ_HANDLED;
+}
+
+static int pxa_rtc_open(struct device *dev)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+ int ret;
+
+ ret = request_irq(pxa_rtc->irq_1Hz, pxa_rtc_irq, IRQF_DISABLED,
+ "rtc 1Hz", dev);
+ if (ret < 0) {
+ dev_err(dev, "can't get irq %i, err %d\n", pxa_rtc->irq_1Hz,
+ ret);
+ goto err_irq_1Hz;
+ }
+ ret = request_irq(pxa_rtc->irq_Alrm, pxa_rtc_irq, IRQF_DISABLED,
+ "rtc Alrm", dev);
+ if (ret < 0) {
+ dev_err(dev, "can't get irq %i, err %d\n", pxa_rtc->irq_Alrm,
+ ret);
+ goto err_irq_Alrm;
+ }
+
+ return 0;
+
+err_irq_Alrm:
+ free_irq(pxa_rtc->irq_1Hz, dev);
+err_irq_1Hz:
+ return ret;
+}
+
+static void pxa_rtc_release(struct device *dev)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+
+ spin_lock_irq(&pxa_rtc->lock);
+ rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE);
+ spin_unlock_irq(&pxa_rtc->lock);
+
+ free_irq(pxa_rtc->irq_Alrm, dev);
+ free_irq(pxa_rtc->irq_1Hz, dev);
+}
+
+static int pxa_periodic_irq_set_freq(struct device *dev, int freq)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+ int period_ms;
+
+ if (freq < 1 || freq > MAXFREQ_PERIODIC)
+ return -EINVAL;
+
+ period_ms = 1000 / freq;
+ rtc_writel(pxa_rtc, PIAR, period_ms);
+
+ return 0;
+}
+
+static int pxa_periodic_irq_set_state(struct device *dev, int enabled)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+
+ if (enabled)
+ rtsr_set_bits(pxa_rtc, RTSR_PIALE | RTSR_PICE);
+ else
+ rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_PICE);
+
+ return 0;
+}
+
+static int pxa_rtc_ioctl(struct device *dev, unsigned int cmd,
+ unsigned long arg)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+ int ret = 0;
+
+ spin_lock_irq(&pxa_rtc->lock);
+ switch (cmd) {
+ case RTC_AIE_OFF:
+ rtsr_clear_bits(pxa_rtc, RTSR_RDALE1);
+ break;
+ case RTC_AIE_ON:
+ rtsr_set_bits(pxa_rtc, RTSR_RDALE1);
+ break;
+ case RTC_UIE_OFF:
+ rtsr_clear_bits(pxa_rtc, RTSR_HZE);
+ break;
+ case RTC_UIE_ON:
+ rtsr_set_bits(pxa_rtc, RTSR_HZE);
+ break;
+ default:
+ ret = -ENOIOCTLCMD;
+ }
+
+ spin_unlock_irq(&pxa_rtc->lock);
+ return ret;
+}
+
+static int pxa_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+ u32 rycr, rdcr;
+
+ rycr = rtc_readl(pxa_rtc, RYCR);
+ rdcr = rtc_readl(pxa_rtc, RDCR);
+
+ tm_calc(rycr, rdcr, tm);
+ return 0;
+}
+
+static int pxa_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+
+ rtc_writel(pxa_rtc, RYCR, ryxr_calc(tm));
+ rtc_writel(pxa_rtc, RDCR, rdxr_calc(tm));
+
+ return 0;
+}
+
+static int pxa_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+ u32 rtsr, ryar, rdar;
+
+ ryar = rtc_readl(pxa_rtc, RYAR1);
+ rdar = rtc_readl(pxa_rtc, RDAR1);
+ tm_calc(ryar, rdar, &alrm->time);
+
+ rtsr = rtc_readl(pxa_rtc, RTSR);
+ alrm->enabled = (rtsr & RTSR_RDALE1) ? 1 : 0;
+ alrm->pending = (rtsr & RTSR_RDAL1) ? 1 : 0;
+ return 0;
+}
+
+static int pxa_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+ u32 rtsr;
+
+ spin_lock_irq(&pxa_rtc->lock);
+
+ rtc_writel(pxa_rtc, RYAR1, ryxr_calc(&alrm->time));
+ rtc_writel(pxa_rtc, RDAR1, rdxr_calc(&alrm->time));
+
+ rtsr = rtc_readl(pxa_rtc, RTSR);
+ if (alrm->enabled)
+ rtsr |= RTSR_RDALE1;
+ else
+ rtsr &= ~RTSR_RDALE1;
+ rtc_writel(pxa_rtc, RTSR, rtsr);
+
+ spin_unlock_irq(&pxa_rtc->lock);
+
+ return 0;
+}
+
+static int pxa_rtc_proc(struct device *dev, struct seq_file *seq)
+{
+ struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
+
+ seq_printf(seq, "trim/divider\t: 0x%08x\n", rtc_readl(pxa_rtc, RTTR));
+ seq_printf(seq, "update_IRQ\t: %s\n",
+ (rtc_readl(pxa_rtc, RTSR) & RTSR_HZE) ? "yes" : "no");
+ seq_printf(seq, "periodic_IRQ\t: %s\n",
+ (rtc_readl(pxa_rtc, RTSR) & RTSR_PIALE) ? "yes" : "no");
+ seq_printf(seq, "periodic_freq\t: %u\n", rtc_readl(pxa_rtc, PIAR));
+
+ return 0;
+}
+
+static const struct rtc_class_ops pxa_rtc_ops = {
+ .open = pxa_rtc_open,
+ .release = pxa_rtc_release,
+ .ioctl = pxa_rtc_ioctl,
+ .read_time = pxa_rtc_read_time,
+ .set_time = pxa_rtc_set_time,
+ .read_alarm = pxa_rtc_read_alarm,
+ .set_alarm = pxa_rtc_set_alarm,
+ .proc = pxa_rtc_proc,
+ .irq_set_state = pxa_periodic_irq_set_state,
+ .irq_set_freq = pxa_periodic_irq_set_freq,
+};
+
+static int __init pxa_rtc_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct pxa_rtc *pxa_rtc;
+ int ret;
+ u32 rttr;
+
+ pxa_rtc = kzalloc(sizeof(struct pxa_rtc), GFP_KERNEL);
+ if (!pxa_rtc)
+ return -ENOMEM;
+
+ spin_lock_init(&pxa_rtc->lock);
+ platform_set_drvdata(pdev, pxa_rtc);
+
+ ret = -ENXIO;
+ pxa_rtc->ress = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!pxa_rtc->ress) {
+ dev_err(dev, "No I/O memory resource defined\n");
+ goto err_ress;
+ }
+
+ pxa_rtc->irq_1Hz = platform_get_irq(pdev, 0);
+ if (pxa_rtc->irq_1Hz < 0) {
+ dev_err(dev, "No 1Hz IRQ resource defined\n");
+ goto err_ress;
+ }
+ pxa_rtc->irq_Alrm = platform_get_irq(pdev, 1);
+ if (pxa_rtc->irq_Alrm < 0) {
+ dev_err(dev, "No alarm IRQ resource defined\n");
+ goto err_ress;
+ }
+
+ ret = -ENOMEM;
+ pxa_rtc->base = ioremap(pxa_rtc->ress->start,
+ resource_size(pxa_rtc->ress));
+ if (!pxa_rtc->base) {
+ dev_err(&pdev->dev, "Unable to map pxa RTC I/O memory\n");
+ goto err_map;
+ }
+
+ /*
+ * If the clock divider is uninitialized then reset it to the
+ * default value to get the 1Hz clock.
+ */
+ if (rtc_readl(pxa_rtc, RTTR) == 0) {
+ rttr = RTC_DEF_DIVIDER + (RTC_DEF_TRIM << 16);
+ rtc_writel(pxa_rtc, RTTR, rttr);
+ dev_warn(dev, "warning: initializing default clock"
+ " divider/trim value\n");
+ }
+
+ rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE);
+
+ pxa_rtc->rtc = rtc_device_register("pxa-rtc", &pdev->dev, &pxa_rtc_ops,
+ THIS_MODULE);
+ ret = PTR_ERR(pxa_rtc->rtc);
+ if (IS_ERR(pxa_rtc->rtc)) {
+ dev_err(dev, "Failed to register RTC device -> %d\n", ret);
+ goto err_rtc_reg;
+ }
+
+ device_init_wakeup(dev, 1);
+
+ return 0;
+
+err_rtc_reg:
+ iounmap(pxa_rtc->base);
+err_ress:
+err_map:
+ kfree(pxa_rtc);
+ return ret;
+}
+
+static int __exit pxa_rtc_remove(struct platform_device *pdev)
+{
+ struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);
+
+ rtc_device_unregister(pxa_rtc->rtc);
+
+ spin_lock_irq(&pxa_rtc->lock);
+ iounmap(pxa_rtc->base);
+ spin_unlock_irq(&pxa_rtc->lock);
+
+ kfree(pxa_rtc);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int pxa_rtc_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);
+
+ if (device_may_wakeup(&pdev->dev))
+ enable_irq_wake(pxa_rtc->irq_Alrm);
+ return 0;
+}
+
+static int pxa_rtc_resume(struct platform_device *pdev)
+{
+ struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);
+
+ if (device_may_wakeup(&pdev->dev))
+ disable_irq_wake(pxa_rtc->irq_Alrm);
+ return 0;
+}
+#else
+#define pxa_rtc_suspend NULL
+#define pxa_rtc_resume NULL
+#endif
+
+static struct platform_driver pxa_rtc_driver = {
+ .remove = __exit_p(pxa_rtc_remove),
+ .suspend = pxa_rtc_suspend,
+ .resume = pxa_rtc_resume,
+ .driver = {
+ .name = "pxa-rtc",
+ },
+};
+
+static int __init pxa_rtc_init(void)
+{
+ if (cpu_is_pxa27x() || cpu_is_pxa3xx())
+ return platform_driver_probe(&pxa_rtc_driver, pxa_rtc_probe);
+
+ return -ENODEV;
+}
+
+static void __exit pxa_rtc_exit(void)
+{
+ platform_driver_unregister(&pxa_rtc_driver);
+}
+
+module_init(pxa_rtc_init);
+module_exit(pxa_rtc_exit);
+
+MODULE_AUTHOR("Robert Jarzmik");
+MODULE_DESCRIPTION("PXA27x/PXA3xx Realtime Clock Driver (RTC)");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:pxa-rtc");