1 files changed, 194 insertions, 129 deletions

diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c
index 572e9534b59..ea96492357b 100644
--- a/drivers/rtc/rtc-stmp3xxx.c
+++ b/drivers/rtc/rtc-stmp3xxx.c
@@ -6,6 +6,7 @@
  *
  * Copyright 2008 Freescale Semiconductor, Inc. All Rights Reserved.
  * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
+ * Copyright 2011 Wolfram Sang, Pengutronix e.K.
  */
 
 /*
@@ -18,42 +19,141 @@
  */
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/io.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/interrupt.h>
+#include <linux/delay.h>
 #include <linux/rtc.h>
 #include <linux/slab.h>
+#include <linux/of_device.h>
+#include <linux/of.h>
+#include <linux/stmp_device.h>
+#include <linux/stmp3xxx_rtc_wdt.h>
 
-#include <mach/platform.h>
-#include <mach/stmp3xxx.h>
-#include <mach/regs-rtc.h>
+#define STMP3XXX_RTC_CTRL			0x0
+#define STMP3XXX_RTC_CTRL_SET			0x4
+#define STMP3XXX_RTC_CTRL_CLR			0x8
+#define STMP3XXX_RTC_CTRL_ALARM_IRQ_EN		0x00000001
+#define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN	0x00000002
+#define STMP3XXX_RTC_CTRL_ALARM_IRQ		0x00000004
+#define STMP3XXX_RTC_CTRL_WATCHDOGEN		0x00000010
+
+#define STMP3XXX_RTC_STAT			0x10
+#define STMP3XXX_RTC_STAT_STALE_SHIFT		16
+#define STMP3XXX_RTC_STAT_RTC_PRESENT		0x80000000
+
+#define STMP3XXX_RTC_SECONDS			0x30
+
+#define STMP3XXX_RTC_ALARM			0x40
+
+#define STMP3XXX_RTC_WATCHDOG			0x50
+
+#define STMP3XXX_RTC_PERSISTENT0		0x60
+#define STMP3XXX_RTC_PERSISTENT0_SET		0x64
+#define STMP3XXX_RTC_PERSISTENT0_CLR		0x68
+#define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN	0x00000002
+#define STMP3XXX_RTC_PERSISTENT0_ALARM_EN	0x00000004
+#define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE	0x00000080
+
+#define STMP3XXX_RTC_PERSISTENT1		0x70
+/* missing bitmask in headers */
+#define STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER	0x80000000
 
 struct stmp3xxx_rtc_data {
 	struct rtc_device *rtc;
-	unsigned irq_count;
 	void __iomem *io;
-	int irq_alarm, irq_1msec;
+	int irq_alarm;
+};
+
+#if IS_ENABLED(CONFIG_STMP3XXX_RTC_WATCHDOG)
+/**
+ * stmp3xxx_wdt_set_timeout - configure the watchdog inside the STMP3xxx RTC
+ * @dev: the parent device of the watchdog (= the RTC)
+ * @timeout: the desired value for the timeout register of the watchdog.
+ *           0 disables the watchdog
+ *
+ * The watchdog needs one register and two bits which are in the RTC domain.
+ * To handle the resource conflict, the RTC driver will create another
+ * platform_device for the watchdog driver as a child of the RTC device.
+ * The watchdog driver is passed the below accessor function via platform_data
+ * to configure the watchdog. Locking is not needed because accessing SET/CLR
+ * registers is atomic.
+ */
+
+static void stmp3xxx_wdt_set_timeout(struct device *dev, u32 timeout)
+{
+	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
+
+	if (timeout) {
+		writel(timeout, rtc_data->io + STMP3XXX_RTC_WATCHDOG);
+		writel(STMP3XXX_RTC_CTRL_WATCHDOGEN,
+		       rtc_data->io + STMP3XXX_RTC_CTRL + STMP_OFFSET_REG_SET);
+		writel(STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER,
+		       rtc_data->io + STMP3XXX_RTC_PERSISTENT1 + STMP_OFFSET_REG_SET);
+	} else {
+		writel(STMP3XXX_RTC_CTRL_WATCHDOGEN,
+		       rtc_data->io + STMP3XXX_RTC_CTRL + STMP_OFFSET_REG_CLR);
+		writel(STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER,
+		       rtc_data->io + STMP3XXX_RTC_PERSISTENT1 + STMP_OFFSET_REG_CLR);
+	}
+}
+
+static struct stmp3xxx_wdt_pdata wdt_pdata = {
+	.wdt_set_timeout = stmp3xxx_wdt_set_timeout,
 };
 
-static void stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data)
+static void stmp3xxx_wdt_register(struct platform_device *rtc_pdev)
+{
+	struct platform_device *wdt_pdev =
+		platform_device_alloc("stmp3xxx_rtc_wdt", rtc_pdev->id);
+
+	if (wdt_pdev) {
+		wdt_pdev->dev.parent = &rtc_pdev->dev;
+		wdt_pdev->dev.platform_data = &wdt_pdata;
+		platform_device_add(wdt_pdev);
+	}
+}
+#else
+static void stmp3xxx_wdt_register(struct platform_device *rtc_pdev)
 {
+}
+#endif /* CONFIG_STMP3XXX_RTC_WATCHDOG */
+
+static int stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data)
+{
+	int timeout = 5000; /* 3ms according to i.MX28 Ref Manual */
 	/*
-	 * The datasheet doesn't say which way round the
-	 * NEW_REGS/STALE_REGS bitfields go. In fact it's 0x1=P0,
-	 * 0x2=P1, .., 0x20=P5, 0x40=ALARM, 0x80=SECONDS
+	 * The i.MX28 Applications Processor Reference Manual, Rev. 1, 2010
+	 * states:
+	 * | The order in which registers are updated is
+	 * | Persistent 0, 1, 2, 3, 4, 5, Alarm, Seconds.
+	 * | (This list is in bitfield order, from LSB to MSB, as they would
+	 * | appear in the STALE_REGS and NEW_REGS bitfields of the HW_RTC_STAT
+	 * | register. For example, the Seconds register corresponds to
+	 * | STALE_REGS or NEW_REGS containing 0x80.)
 	 */
-	while (__raw_readl(rtc_data->io + HW_RTC_STAT) &
-			BF(0x80, RTC_STAT_STALE_REGS))
-		cpu_relax();
+	do {
+		if (!(readl(rtc_data->io + STMP3XXX_RTC_STAT) &
+				(0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT)))
+			return 0;
+		udelay(1);
+	} while (--timeout > 0);
+	return (readl(rtc_data->io + STMP3XXX_RTC_STAT) &
+		(0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT)) ? -ETIME : 0;
 }
 
 /* Time read/write */
 static int stmp3xxx_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
 {
+	int ret;
 	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
 
-	stmp3xxx_wait_time(rtc_data);
-	rtc_time_to_tm(__raw_readl(rtc_data->io + HW_RTC_SECONDS), rtc_tm);
+	ret = stmp3xxx_wait_time(rtc_data);
+	if (ret)
+		return ret;
+
+	rtc_time_to_tm(readl(rtc_data->io + STMP3XXX_RTC_SECONDS), rtc_tm);
 	return 0;
 }
 
@@ -61,56 +161,42 @@ static int stmp3xxx_rtc_set_mmss(struct device *dev, unsigned long t)
 {
 	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
 
-	__raw_writel(t, rtc_data->io + HW_RTC_SECONDS);
-	stmp3xxx_wait_time(rtc_data);
-	return 0;
+	writel(t, rtc_data->io + STMP3XXX_RTC_SECONDS);
+	return stmp3xxx_wait_time(rtc_data);
 }
 
 /* interrupt(s) handler */
 static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id)
 {
 	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev_id);
-	u32 status;
-	u32 events = 0;
-
-	status = __raw_readl(rtc_data->io + HW_RTC_CTRL) &
-			(BM_RTC_CTRL_ALARM_IRQ | BM_RTC_CTRL_ONEMSEC_IRQ);
+	u32 status = readl(rtc_data->io + STMP3XXX_RTC_CTRL);
 
-	if (status & BM_RTC_CTRL_ALARM_IRQ) {
-		stmp3xxx_clearl(BM_RTC_CTRL_ALARM_IRQ,
-				rtc_data->io + HW_RTC_CTRL);
-		events |= RTC_AF | RTC_IRQF;
+	if (status & STMP3XXX_RTC_CTRL_ALARM_IRQ) {
+		writel(STMP3XXX_RTC_CTRL_ALARM_IRQ,
+				rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
+		rtc_update_irq(rtc_data->rtc, 1, RTC_AF | RTC_IRQF);
+		return IRQ_HANDLED;
 	}
 
-	if (status & BM_RTC_CTRL_ONEMSEC_IRQ) {
-		stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ,
-				rtc_data->io + HW_RTC_CTRL);
-		if (++rtc_data->irq_count % 1000 == 0) {
-			events |= RTC_UF | RTC_IRQF;
-			rtc_data->irq_count = 0;
-		}
-	}
-
-	if (events)
-		rtc_update_irq(rtc_data->rtc, 1, events);
-
-	return IRQ_HANDLED;
+	return IRQ_NONE;
 }
 
 static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled)
 {
 	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
-	void __iomem *p = rtc_data->io + HW_RTC_PERSISTENT0,
-		     *ctl = rtc_data->io + HW_RTC_CTRL;
 
 	if (enabled) {
-		stmp3xxx_setl(BM_RTC_PERSISTENT0_ALARM_EN |
-			      BM_RTC_PERSISTENT0_ALARM_WAKE_EN, p);
-		stmp3xxx_setl(BM_RTC_CTRL_ALARM_IRQ_EN, ctl);
+		writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
+				STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
+				rtc_data->io + STMP3XXX_RTC_PERSISTENT0_SET);
+		writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
+				rtc_data->io + STMP3XXX_RTC_CTRL_SET);
 	} else {
-		stmp3xxx_clearl(BM_RTC_PERSISTENT0_ALARM_EN |
-			      BM_RTC_PERSISTENT0_ALARM_WAKE_EN, p);
-		stmp3xxx_clearl(BM_RTC_CTRL_ALARM_IRQ_EN, ctl);
+		writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
+				STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
+				rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
+		writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
+				rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
 	}
 	return 0;
 }
@@ -119,7 +205,7 @@ static int stmp3xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
 {
 	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
 
-	rtc_time_to_tm(__raw_readl(rtc_data->io + HW_RTC_ALARM), &alm->time);
+	rtc_time_to_tm(readl(rtc_data->io + STMP3XXX_RTC_ALARM), &alm->time);
 	return 0;
 }
 
@@ -129,7 +215,10 @@ static int stmp3xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
 	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
 
 	rtc_tm_to_time(&alm->time, &t);
-	__raw_writel(t, rtc_data->io + HW_RTC_ALARM);
+	writel(t, rtc_data->io + STMP3XXX_RTC_ALARM);
+
+	stmp3xxx_alarm_irq_enable(dev, alm->enabled);
+
 	return 0;
 }
 
@@ -149,13 +238,8 @@ static int stmp3xxx_rtc_remove(struct platform_device *pdev)
 	if (!rtc_data)
 		return 0;
 
-	stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ_EN | BM_RTC_CTRL_ALARM_IRQ_EN,
-			rtc_data->io + HW_RTC_CTRL);
-	free_irq(rtc_data->irq_alarm, &pdev->dev);
-	free_irq(rtc_data->irq_1msec, &pdev->dev);
-	rtc_device_unregister(rtc_data->rtc);
-	iounmap(rtc_data->io);
-	kfree(rtc_data);
+	writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
+			rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
 
 	return 0;
 }
@@ -166,125 +250,106 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev)
 	struct resource *r;
 	int err;
 
-	rtc_data = kzalloc(sizeof *rtc_data, GFP_KERNEL);
+	rtc_data = devm_kzalloc(&pdev->dev, sizeof(*rtc_data), GFP_KERNEL);
 	if (!rtc_data)
 		return -ENOMEM;
 
 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!r) {
 		dev_err(&pdev->dev, "failed to get resource\n");
-		err = -ENXIO;
-		goto out_free;
+		return -ENXIO;
 	}
 
-	rtc_data->io = ioremap(r->start, resource_size(r));
+	rtc_data->io = devm_ioremap(&pdev->dev, r->start, resource_size(r));
 	if (!rtc_data->io) {
 		dev_err(&pdev->dev, "ioremap failed\n");
-		err = -EIO;
-		goto out_free;
+		return -EIO;
 	}
 
 	rtc_data->irq_alarm = platform_get_irq(pdev, 0);
-	rtc_data->irq_1msec = platform_get_irq(pdev, 1);
 
-	if (!(__raw_readl(HW_RTC_STAT + rtc_data->io) &
-			BM_RTC_STAT_RTC_PRESENT)) {
+	if (!(readl(STMP3XXX_RTC_STAT + rtc_data->io) &
+			STMP3XXX_RTC_STAT_RTC_PRESENT)) {
 		dev_err(&pdev->dev, "no device onboard\n");
-		err = -ENODEV;
-		goto out_remap;
+		return -ENODEV;
 	}
 
-	stmp3xxx_reset_block(rtc_data->io, true);
-	stmp3xxx_clearl(BM_RTC_PERSISTENT0_ALARM_EN |
-			BM_RTC_PERSISTENT0_ALARM_WAKE_EN |
-			BM_RTC_PERSISTENT0_ALARM_WAKE,
-			rtc_data->io + HW_RTC_PERSISTENT0);
-	rtc_data->rtc = rtc_device_register(pdev->name, &pdev->dev,
-				&stmp3xxx_rtc_ops, THIS_MODULE);
-	if (IS_ERR(rtc_data->rtc)) {
-		err = PTR_ERR(rtc_data->rtc);
-		goto out_remap;
-	}
+	platform_set_drvdata(pdev, rtc_data);
 
-	rtc_data->irq_count = 0;
-	err = request_irq(rtc_data->irq_alarm, stmp3xxx_rtc_interrupt,
-			IRQF_DISABLED, "RTC alarm", &pdev->dev);
+	err = stmp_reset_block(rtc_data->io);
 	if (err) {
-		dev_err(&pdev->dev, "Cannot claim IRQ%d\n",
-			rtc_data->irq_alarm);
-		goto out_irq_alarm;
+		dev_err(&pdev->dev, "stmp_reset_block failed: %d\n", err);
+		return err;
 	}
-	err = request_irq(rtc_data->irq_1msec, stmp3xxx_rtc_interrupt,
-			IRQF_DISABLED, "RTC tick", &pdev->dev);
+
+	writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
+			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
+			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
+			rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
+
+	writel(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN |
+			STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
+			rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
+
+	rtc_data->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
+				&stmp3xxx_rtc_ops, THIS_MODULE);
+	if (IS_ERR(rtc_data->rtc))
+		return PTR_ERR(rtc_data->rtc);
+
+	err = devm_request_irq(&pdev->dev, rtc_data->irq_alarm,
+			stmp3xxx_rtc_interrupt, 0, "RTC alarm", &pdev->dev);
 	if (err) {
 		dev_err(&pdev->dev, "Cannot claim IRQ%d\n",
-			rtc_data->irq_1msec);
-		goto out_irq1;
+			rtc_data->irq_alarm);
+		return err;
 	}
 
-	platform_set_drvdata(pdev, rtc_data);
-
+	stmp3xxx_wdt_register(pdev);
 	return 0;
-
-out_irq1:
-	free_irq(rtc_data->irq_alarm, &pdev->dev);
-out_irq_alarm:
-	stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ_EN | BM_RTC_CTRL_ALARM_IRQ_EN,
-			rtc_data->io + HW_RTC_CTRL);
-	rtc_device_unregister(rtc_data->rtc);
-out_remap:
-	iounmap(rtc_data->io);
-out_free:
-	kfree(rtc_data);
-	return err;
 }
 
-#ifdef CONFIG_PM
-static int stmp3xxx_rtc_suspend(struct platform_device *dev, pm_message_t state)
+#ifdef CONFIG_PM_SLEEP
+static int stmp3xxx_rtc_suspend(struct device *dev)
 {
 	return 0;
 }
 
-static int stmp3xxx_rtc_resume(struct platform_device *dev)
+static int stmp3xxx_rtc_resume(struct device *dev)
 {
-	struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(dev);
+	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
 
-	stmp3xxx_reset_block(rtc_data->io, true);
-	stmp3xxx_clearl(BM_RTC_PERSISTENT0_ALARM_EN |
-			BM_RTC_PERSISTENT0_ALARM_WAKE_EN |
-			BM_RTC_PERSISTENT0_ALARM_WAKE,
-			rtc_data->io + HW_RTC_PERSISTENT0);
+	stmp_reset_block(rtc_data->io);
+	writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
+			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
+			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
+			rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
 	return 0;
 }
-#else
-#define stmp3xxx_rtc_suspend	NULL
-#define stmp3xxx_rtc_resume	NULL
 #endif
 
+static SIMPLE_DEV_PM_OPS(stmp3xxx_rtc_pm_ops, stmp3xxx_rtc_suspend,
+			stmp3xxx_rtc_resume);
+
+static const struct of_device_id rtc_dt_ids[] = {
+	{ .compatible = "fsl,stmp3xxx-rtc", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, rtc_dt_ids);
+
 static struct platform_driver stmp3xxx_rtcdrv = {
 	.probe		= stmp3xxx_rtc_probe,
 	.remove		= stmp3xxx_rtc_remove,
-	.suspend	= stmp3xxx_rtc_suspend,
-	.resume		= stmp3xxx_rtc_resume,
 	.driver		= {
 		.name	= "stmp3xxx-rtc",
 		.owner	= THIS_MODULE,
+		.pm	= &stmp3xxx_rtc_pm_ops,
+		.of_match_table = rtc_dt_ids,
 	},
 };
 
-static int __init stmp3xxx_rtc_init(void)
-{
-	return platform_driver_register(&stmp3xxx_rtcdrv);
-}
-
-static void __exit stmp3xxx_rtc_exit(void)
-{
-	platform_driver_unregister(&stmp3xxx_rtcdrv);
-}
-
-module_init(stmp3xxx_rtc_init);
-module_exit(stmp3xxx_rtc_exit);
+module_platform_driver(stmp3xxx_rtcdrv);
 
 MODULE_DESCRIPTION("STMP3xxx RTC Driver");
-MODULE_AUTHOR("dmitry pervushin <dpervushin@embeddedalley.com>");
+MODULE_AUTHOR("dmitry pervushin <dpervushin@embeddedalley.com> and "
+		"Wolfram Sang <w.sang@pengutronix.de>");
 MODULE_LICENSE("GPL");