This RTC also includes a watchdog timer. Provide an accessor function
for it to be picked up by a watchdog driver. Also register the
platform_device here to get the boot-time dependencies right.
Signed-off-by: Wolfram Sang <w.sang@xxxxxxxxxxxxxx>
Cc: Alessandro Zummo <alessandro.zummo@xxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/rtc/rtc-stmp3xxx.c | 64 ++++++++++++++++++++++++++++++++++++++
include/linux/stmp3xxx_rtc_wdt.h | 15 +++++++++
2 files changed, 79 insertions(+), 0 deletions(-)
create mode 100644 include/linux/stmp3xxx_rtc_wdt.h
diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c
index 1028786..2cf8858 100644
--- a/drivers/rtc/rtc-stmp3xxx.c
+++ b/drivers/rtc/rtc-stmp3xxx.c
@@ -25,8 +25,10 @@
#include <linux/interrupt.h>
#include <linux/rtc.h>
#include <linux/slab.h>
+#include <linux/stmp3xxx_rtc_wdt.h>
#include <mach/common.h>
+#include <mach/mxs.h>
#define STMP3XXX_RTC_CTRL 0x0
#define STMP3XXX_RTC_CTRL_SET 0x4
@@ -34,6 +36,7 @@
#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
@@ -43,6 +46,8 @@
#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
@@ -50,12 +55,70 @@
#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;
void __iomem *io;
int irq_alarm;
};
+#if defined(CONFIG_STMP3XXX_RTC_WATCHDOG) || defined(CONFIG_STMP3XXX_RTC_WATCHDOG_MODULE)
+/**
+ * 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.
+ */
+
+void stmp3xxx_wdt_set_timeout(struct device *dev, u32 timeout)
+{
+ struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
+ void __iomem *base;
+
+ if (timeout) {
+ writel(timeout, rtc_data->io + STMP3XXX_RTC_WATCHDOG);
+ base = rtc_data->io + MXS_SET_ADDR;
+ } else {
+ base = rtc_data->io + MXS_CLR_ADDR;
+ }
+ writel(STMP3XXX_RTC_CTRL_WATCHDOGEN, base + STMP3XXX_RTC_CTRL);
+ writel(STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER,
+ base + STMP3XXX_RTC_PERSISTENT1);
+}
+
+static struct stmp3xxx_wdt_pdata wdt_pdata = {
+ .wdt_set_timeout = stmp3xxx_wdt_set_timeout,
+};
+
+static struct platform_device stmp3xxx_wdt_pdev = {
+ .name = "stmp3xxx_rtc_wdt",
+ .dev = {
+ .platform_data = &wdt_pdata,
+ },
+};
+
+static void stmp3xxx_wdt_register(struct platform_device *rtc_pdev)
+{
+ stmp3xxx_wdt_pdev.dev.parent = &rtc_pdev->dev;
+ stmp3xxx_wdt_pdev.id = rtc_pdev->id;
+ platform_device_register(&stmp3xxx_wdt_pdev);
+}
+#else
+static void stmp3xxx_wdt_register(struct device *dev)
+{
+}
+#endif /* CONFIG_STMP3XXX_RTC_WATCHDOG */
+
static void stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data)
{
/*
@@ -231,6 +294,7 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev)
goto out_irq_alarm;
}
+ stmp3xxx_wdt_register(pdev);
return 0;
out_irq_alarm:
diff --git a/include/linux/stmp3xxx_rtc_wdt.h b/include/linux/stmp3xxx_rtc_wdt.h
new file mode 100644
index 0000000..1dd12c9
--- /dev/null
+++ b/include/linux/stmp3xxx_rtc_wdt.h
@@ -0,0 +1,15 @@
+/*
+ * stmp3xxx_rtc_wdt.h
+ *
+ * Copyright (C) 2011 Wolfram Sang, Pengutronix e.K.
+ *
+ * This file is released under the GPLv2.
+ */
+#ifndef __LINUX_STMP3XXX_RTC_WDT_H
+#define __LINUX_STMP3XXX_RTC_WDT_H
+
+struct stmp3xxx_wdt_pdata {
+ void (*wdt_set_timeout)(struct device *dev, u32 timeout);
+};
+
+#endif /* __LINUX_STMP3XXX_RTC_WDT_H */
--
1.7.2.5
--
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