* [PATCH 1/3] rtc: stmp3xxx: add wdt-accessor function
2011-12-08 17:19 [PATCH 0/3] watchdog: new driver for STMP3xxx/MX23/MX28 Wolfram Sang
@ 2011-12-08 17:19 ` Wolfram Sang
2011-12-09 0:27 ` Shawn Guo
2011-12-08 17:19 ` [PATCH 2/3] watchdog: add new driver for STMP3xxx and i.MX23/28 Wolfram Sang
2011-12-08 17:19 ` [PATCH 3/3] watchdog: remove old STMP driver Wolfram Sang
2 siblings, 1 reply; 6+ messages in thread
From: Wolfram Sang @ 2011-12-08 17:19 UTC (permalink / raw)
To: linux-watchdog
Cc: Wim Van Sebroeck, Andrew Morton, linux-arm-kernel, Wolfram Sang,
Alessandro Zummo, rtc-linux
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@pengutronix.de>
Cc: Alessandro Zummo <alessandro.zummo@towertech.it>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: rtc-linux@googlegroups.com
---
Andrew, Wim: Alessandro was not around in the last weeks, so I'd suggest this
patch goes via the watchdog-tree together with the rest of this series if it
passes the review of the watchdog-list? All changes here are in preparation for
the watchdog driver and do not affect the general RTC. Concerns from V1 have
been hopefully addressed (no EXPORT_SYMBOL anymore, better documentation)
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 7315068..811b44b 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 */
--
1.7.7.3
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH 1/3] rtc: stmp3xxx: add wdt-accessor function
2011-12-08 17:19 ` [PATCH 1/3] rtc: stmp3xxx: add wdt-accessor function Wolfram Sang
@ 2011-12-09 0:27 ` Shawn Guo
2011-12-09 9:22 ` Wolfram Sang
0 siblings, 1 reply; 6+ messages in thread
From: Shawn Guo @ 2011-12-09 0:27 UTC (permalink / raw)
To: Wolfram Sang
Cc: linux-watchdog, Alessandro Zummo, rtc-linux, Wim Van Sebroeck,
Andrew Morton, linux-arm-kernel
Hi Wolfram,
On Thu, Dec 08, 2011 at 06:19:41PM +0100, Wolfram Sang wrote:
> @@ -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);
Passing callback with platform_data will make device tree migration
difficult. Is there any possibility we can save the callback here?
Regards,
Shawn
> +};
> +
> +#endif /* __LINUX_STMP3XXX_RTC_WDT_H */
> --
> 1.7.7.3
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH 1/3] rtc: stmp3xxx: add wdt-accessor function
2011-12-09 0:27 ` Shawn Guo
@ 2011-12-09 9:22 ` Wolfram Sang
0 siblings, 0 replies; 6+ messages in thread
From: Wolfram Sang @ 2011-12-09 9:22 UTC (permalink / raw)
To: Shawn Guo
Cc: linux-watchdog, Alessandro Zummo, rtc-linux, Wim Van Sebroeck,
Andrew Morton, linux-arm-kernel
[-- Attachment #1: Type: text/plain, Size: 1118 bytes --]
On Fri, Dec 09, 2011 at 08:27:24AM +0800, Shawn Guo wrote:
> Hi Wolfram,
>
> On Thu, Dec 08, 2011 at 06:19:41PM +0100, Wolfram Sang wrote:
> > @@ -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);
>
> Passing callback with platform_data will make device tree migration
> difficult. Is there any possibility we can save the callback here?
This won't affect the device tree. The platform_data is not set up per
board. It is the RTC driver which adds the platform_data to the
platform_device which was also created inside the RTC driver. So, device
tree or not, simply enable the watchdog in Kconfig and all will be fine.
--
Pengutronix e.K. | Wolfram Sang |
Industrial Linux Solutions | http://www.pengutronix.de/ |
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 198 bytes --]
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 2/3] watchdog: add new driver for STMP3xxx and i.MX23/28
2011-12-08 17:19 [PATCH 0/3] watchdog: new driver for STMP3xxx/MX23/MX28 Wolfram Sang
2011-12-08 17:19 ` [PATCH 1/3] rtc: stmp3xxx: add wdt-accessor function Wolfram Sang
@ 2011-12-08 17:19 ` Wolfram Sang
2011-12-08 17:19 ` [PATCH 3/3] watchdog: remove old STMP driver Wolfram Sang
2 siblings, 0 replies; 6+ messages in thread
From: Wolfram Sang @ 2011-12-08 17:19 UTC (permalink / raw)
To: linux-watchdog
Cc: Wim Van Sebroeck, Andrew Morton, linux-arm-kernel, Wolfram Sang
Replace the existing STMP3xxx driver because it has enough drawbacks
that a rewrite is apropriate. The new driver is designed to use the
watchdog framework which makes it a lot smaller. It now uses an exported
function from the RTC driver to set up its registers (the old driver
silently reused the hopefully already remapped RTC registers). Also,
this driver is mach independent, while the old one still depends on a
removed mach.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
---
drivers/watchdog/Kconfig | 10 +++
drivers/watchdog/Makefile | 1 +
drivers/watchdog/stmp3xxx_rtc_wdt.c | 139 +++++++++++++++++++++++++++++++++++
3 files changed, 150 insertions(+), 0 deletions(-)
create mode 100644 drivers/watchdog/stmp3xxx_rtc_wdt.c
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 79fd606..f024aa3 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -305,6 +305,16 @@ config STMP3XXX_WATCHDOG
To compile this driver as a module, choose M here: the
module will be called stmp3xxx_wdt.
+config STMP3XXX_RTC_WATCHDOG
+ tristate "Freescale STMP3XXX & i.MX23/28 watchdog"
+ depends on RTC_DRV_STMP
+ select WATCHDOG_CORE
+ help
+ Say Y here to include support for the watchdog timer inside
+ the RTC for the STMP37XX/378X or i.MX23/28 SoC.
+ To compile this driver as a module, choose M here: the
+ module will be called stmp3xxx_rtc_wdt.
+
config NUC900_WATCHDOG
tristate "Nuvoton NUC900 watchdog"
depends on ARCH_W90X900
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index fe893e9..308d248 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -50,6 +50,7 @@ obj-$(CONFIG_DAVINCI_WATCHDOG) += davinci_wdt.o
obj-$(CONFIG_ORION_WATCHDOG) += orion_wdt.o
obj-$(CONFIG_COH901327_WATCHDOG) += coh901327_wdt.o
obj-$(CONFIG_STMP3XXX_WATCHDOG) += stmp3xxx_wdt.o
+obj-$(CONFIG_STMP3XXX_RTC_WATCHDOG) += stmp3xxx_rtc_wdt.o
obj-$(CONFIG_NUC900_WATCHDOG) += nuc900_wdt.o
obj-$(CONFIG_TS72XX_WATCHDOG) += ts72xx_wdt.o
obj-$(CONFIG_IMX2_WDT) += imx2_wdt.o
diff --git a/drivers/watchdog/stmp3xxx_rtc_wdt.c b/drivers/watchdog/stmp3xxx_rtc_wdt.c
new file mode 100644
index 0000000..4351055
--- /dev/null
+++ b/drivers/watchdog/stmp3xxx_rtc_wdt.c
@@ -0,0 +1,139 @@
+/*
+ * Watchdog driver for the RTC based watchdog in STMP3xxx and i.MX23/28
+ *
+ * Author: Wolfram Sang <w.sang@pengutronix.de>
+ *
+ * Copyright (C) 2011 Pengutronix e.K.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/platform_device.h>
+#include <linux/stmp3xxx_rtc_wdt.h>
+
+#define WDOG_TICK_RATE 1000 /* 1 kHz clock */
+#define STMP3XXX_DEFAULT_TIMEOUT 60
+#define STMP3XXX_MAX_TIMEOUT (UINT_MAX / WDOG_TICK_RATE)
+
+static int timeout = STMP3XXX_DEFAULT_TIMEOUT;
+module_param(timeout, uint, 0);
+MODULE_PARM_DESC(timeout, "Watchdog timeout period in seconds from 1 to "
+ __MODULE_STRING(STMP3XXX_MAX_TIMEOUT) ", default "
+ __MODULE_STRING(STMP3XXX_DEFAULT_TIMEOUT));
+
+static int wdt_start(struct watchdog_device *wdd)
+{
+ struct device *dev = watchdog_get_drvdata(wdd);
+ struct stmp3xxx_wdt_pdata *pdata = dev->platform_data;
+
+ pdata->wdt_set_timeout(dev->parent, wdd->timeout * WDOG_TICK_RATE);
+ return 0;
+}
+
+static int wdt_stop(struct watchdog_device *wdd)
+{
+ struct device *dev = watchdog_get_drvdata(wdd);
+ struct stmp3xxx_wdt_pdata *pdata = dev->platform_data;
+
+ pdata->wdt_set_timeout(dev->parent, 0);
+ return 0;
+}
+
+static int wdt_set_timeout(struct watchdog_device *wdd, unsigned new_timeout)
+{
+ struct device *dev = watchdog_get_drvdata(wdd);
+ struct stmp3xxx_wdt_pdata *pdata = dev->platform_data;
+
+ pdata->wdt_set_timeout(dev->parent, new_timeout * WDOG_TICK_RATE);
+ return 0;
+}
+
+static const struct watchdog_info stmp3xxx_wdt_ident = {
+ .options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+ .identity = "STMP3XXX RTC Watchdog",
+};
+
+static const struct watchdog_ops stmp3xxx_wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = wdt_start,
+ .stop = wdt_stop,
+ .set_timeout = wdt_set_timeout,
+};
+
+static struct watchdog_device stmp3xxx_wdd = {
+ .info = &stmp3xxx_wdt_ident,
+ .ops = &stmp3xxx_wdt_ops,
+ .min_timeout = 1,
+ .max_timeout = STMP3XXX_MAX_TIMEOUT,
+ .status = WATCHDOG_NOWAYOUT_INIT_STATUS,
+};
+
+static int __devinit stmp3xxx_wdt_probe(struct platform_device *pdev)
+{
+ int ret;
+
+ watchdog_set_drvdata(&stmp3xxx_wdd, &pdev->dev);
+
+ stmp3xxx_wdd.timeout = clamp_t(unsigned, timeout, 1, STMP3XXX_MAX_TIMEOUT);
+
+ ret = watchdog_register_device(&stmp3xxx_wdd);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "cannot register watchdog device\n");
+ return ret;
+ }
+
+ dev_info(&pdev->dev, "initialized watchdog with timeout %ds\n", timeout);
+ return 0;
+}
+
+static int __devexit stmp3xxx_wdt_remove(struct platform_device *pdev)
+{
+ watchdog_unregister_device(&stmp3xxx_wdd);
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int stmp3xxx_wdt_suspend(struct device *dev)
+{
+ if (stmp3xxx_wdd.status & WDOG_ACTIVE)
+ wdt_stop(&stmp3xxx_wdd);
+
+ return 0;
+}
+
+static int stmp3xxx_wdt_resume(struct device *dev)
+{
+ if (stmp3xxx_wdd.status & WDOG_ACTIVE)
+ wdt_start(&stmp3xxx_wdd);
+
+ return 0;
+}
+
+static const struct dev_pm_ops stmp3xxx_wdt_pm_ops = {
+ .suspend = stmp3xxx_wdt_suspend,
+ .resume = stmp3xxx_wdt_resume,
+};
+#endif
+
+static struct platform_driver stmp3xxx_wdt_driver = {
+ .driver = {
+ .name = "stmp3xxx_rtc_wdt",
+#ifdef CONFIG_PM
+ .pm = &stmp3xxx_wdt_pm_ops,
+#endif
+ },
+ .probe = stmp3xxx_wdt_probe,
+ .remove = __devexit_p(stmp3xxx_wdt_remove),
+};
+module_platform_driver(stmp3xxx_wdt_driver);
+
+MODULE_DESCRIPTION("STMP3XXX RTC Watchdog Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
--
1.7.7.3
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH 3/3] watchdog: remove old STMP driver
2011-12-08 17:19 [PATCH 0/3] watchdog: new driver for STMP3xxx/MX23/MX28 Wolfram Sang
2011-12-08 17:19 ` [PATCH 1/3] rtc: stmp3xxx: add wdt-accessor function Wolfram Sang
2011-12-08 17:19 ` [PATCH 2/3] watchdog: add new driver for STMP3xxx and i.MX23/28 Wolfram Sang
@ 2011-12-08 17:19 ` Wolfram Sang
2 siblings, 0 replies; 6+ messages in thread
From: Wolfram Sang @ 2011-12-08 17:19 UTC (permalink / raw)
To: linux-watchdog
Cc: Wim Van Sebroeck, Andrew Morton, linux-arm-kernel, Wolfram Sang
Now that the new driver is in place, we can remove the old one.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
---
drivers/watchdog/Kconfig | 9 --
drivers/watchdog/Makefile | 1 -
drivers/watchdog/stmp3xxx_wdt.c | 297 ---------------------------------------
3 files changed, 0 insertions(+), 307 deletions(-)
delete mode 100644 drivers/watchdog/stmp3xxx_wdt.c
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index f024aa3..2fe4981 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -296,15 +296,6 @@ config TWL4030_WATCHDOG
Support for TI TWL4030 watchdog. Say 'Y' here to enable the
watchdog timer support for TWL4030 chips.
-config STMP3XXX_WATCHDOG
- tristate "Freescale STMP3XXX watchdog"
- depends on ARCH_STMP3XXX
- help
- Say Y here if to include support for the watchdog timer
- for the Sigmatel STMP37XX/378X SoC.
- To compile this driver as a module, choose M here: the
- module will be called stmp3xxx_wdt.
-
config STMP3XXX_RTC_WATCHDOG
tristate "Freescale STMP3XXX & i.MX23/28 watchdog"
depends on RTC_DRV_STMP
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 308d248..ac451d6 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -49,7 +49,6 @@ obj-$(CONFIG_IOP_WATCHDOG) += iop_wdt.o
obj-$(CONFIG_DAVINCI_WATCHDOG) += davinci_wdt.o
obj-$(CONFIG_ORION_WATCHDOG) += orion_wdt.o
obj-$(CONFIG_COH901327_WATCHDOG) += coh901327_wdt.o
-obj-$(CONFIG_STMP3XXX_WATCHDOG) += stmp3xxx_wdt.o
obj-$(CONFIG_STMP3XXX_RTC_WATCHDOG) += stmp3xxx_rtc_wdt.o
obj-$(CONFIG_NUC900_WATCHDOG) += nuc900_wdt.o
obj-$(CONFIG_TS72XX_WATCHDOG) += ts72xx_wdt.o
diff --git a/drivers/watchdog/stmp3xxx_wdt.c b/drivers/watchdog/stmp3xxx_wdt.c
deleted file mode 100644
index ac2346a..0000000
--- a/drivers/watchdog/stmp3xxx_wdt.c
+++ /dev/null
@@ -1,297 +0,0 @@
-/*
- * Watchdog driver for Freescale STMP37XX/STMP378X
- *
- * Author: Vitaly Wool <vital@embeddedalley.com>
- *
- * Copyright 2008 Freescale Semiconductor, Inc. All Rights Reserved.
- * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
- */
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/fs.h>
-#include <linux/miscdevice.h>
-#include <linux/watchdog.h>
-#include <linux/platform_device.h>
-#include <linux/spinlock.h>
-#include <linux/uaccess.h>
-#include <linux/module.h>
-
-#include <mach/platform.h>
-#include <mach/regs-rtc.h>
-
-#define DEFAULT_HEARTBEAT 19
-#define MAX_HEARTBEAT (0x10000000 >> 6)
-
-/* missing bitmask in headers */
-#define BV_RTC_PERSISTENT1_GENERAL__RTC_FORCE_UPDATER 0x80000000
-
-#define WDT_IN_USE 0
-#define WDT_OK_TO_CLOSE 1
-
-#define WDOG_COUNTER_RATE 1000 /* 1 kHz clock */
-
-static DEFINE_SPINLOCK(stmp3xxx_wdt_io_lock);
-static unsigned long wdt_status;
-static const int nowayout = WATCHDOG_NOWAYOUT;
-static int heartbeat = DEFAULT_HEARTBEAT;
-static unsigned long boot_status;
-
-static void wdt_enable(u32 value)
-{
- spin_lock(&stmp3xxx_wdt_io_lock);
- __raw_writel(value, REGS_RTC_BASE + HW_RTC_WATCHDOG);
- stmp3xxx_setl(BM_RTC_CTRL_WATCHDOGEN, REGS_RTC_BASE + HW_RTC_CTRL);
- stmp3xxx_setl(BV_RTC_PERSISTENT1_GENERAL__RTC_FORCE_UPDATER,
- REGS_RTC_BASE + HW_RTC_PERSISTENT1);
- spin_unlock(&stmp3xxx_wdt_io_lock);
-}
-
-static void wdt_disable(void)
-{
- spin_lock(&stmp3xxx_wdt_io_lock);
- stmp3xxx_clearl(BV_RTC_PERSISTENT1_GENERAL__RTC_FORCE_UPDATER,
- REGS_RTC_BASE + HW_RTC_PERSISTENT1);
- stmp3xxx_clearl(BM_RTC_CTRL_WATCHDOGEN, REGS_RTC_BASE + HW_RTC_CTRL);
- spin_unlock(&stmp3xxx_wdt_io_lock);
-}
-
-static void wdt_ping(void)
-{
- wdt_enable(heartbeat * WDOG_COUNTER_RATE);
-}
-
-static int stmp3xxx_wdt_open(struct inode *inode, struct file *file)
-{
- if (test_and_set_bit(WDT_IN_USE, &wdt_status))
- return -EBUSY;
-
- clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
- wdt_ping();
-
- return nonseekable_open(inode, file);
-}
-
-static ssize_t stmp3xxx_wdt_write(struct file *file, const char __user *data,
- size_t len, loff_t *ppos)
-{
- if (len) {
- if (!nowayout) {
- size_t i;
-
- clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
-
- for (i = 0; i != len; i++) {
- char c;
-
- if (get_user(c, data + i))
- return -EFAULT;
- if (c == 'V')
- set_bit(WDT_OK_TO_CLOSE, &wdt_status);
- }
- }
- wdt_ping();
- }
-
- return len;
-}
-
-static const struct watchdog_info ident = {
- .options = WDIOF_CARDRESET |
- WDIOF_MAGICCLOSE |
- WDIOF_SETTIMEOUT |
- WDIOF_KEEPALIVEPING,
- .identity = "STMP3XXX Watchdog",
-};
-
-static long stmp3xxx_wdt_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- void __user *argp = (void __user *)arg;
- int __user *p = argp;
- int new_heartbeat, opts;
- int ret = -ENOTTY;
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- ret = copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
- break;
-
- case WDIOC_GETSTATUS:
- ret = put_user(0, p);
- break;
-
- case WDIOC_GETBOOTSTATUS:
- ret = put_user(boot_status, p);
- break;
-
- case WDIOC_SETOPTIONS:
- if (get_user(opts, p)) {
- ret = -EFAULT;
- break;
- }
- if (opts & WDIOS_DISABLECARD)
- wdt_disable();
- else if (opts & WDIOS_ENABLECARD)
- wdt_ping();
- else {
- pr_debug("%s: unknown option 0x%x\n", __func__, opts);
- ret = -EINVAL;
- break;
- }
- ret = 0;
- break;
-
- case WDIOC_KEEPALIVE:
- wdt_ping();
- ret = 0;
- break;
-
- case WDIOC_SETTIMEOUT:
- if (get_user(new_heartbeat, p)) {
- ret = -EFAULT;
- break;
- }
- if (new_heartbeat <= 0 || new_heartbeat > MAX_HEARTBEAT) {
- ret = -EINVAL;
- break;
- }
-
- heartbeat = new_heartbeat;
- wdt_ping();
- /* Fall through */
-
- case WDIOC_GETTIMEOUT:
- ret = put_user(heartbeat, p);
- break;
- }
- return ret;
-}
-
-static int stmp3xxx_wdt_release(struct inode *inode, struct file *file)
-{
- int ret = 0;
-
- if (!nowayout) {
- if (!test_bit(WDT_OK_TO_CLOSE, &wdt_status)) {
- wdt_ping();
- pr_debug("%s: Device closed unexpectdly\n", __func__);
- ret = -EINVAL;
- } else {
- wdt_disable();
- clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
- }
- }
- clear_bit(WDT_IN_USE, &wdt_status);
-
- return ret;
-}
-
-static const struct file_operations stmp3xxx_wdt_fops = {
- .owner = THIS_MODULE,
- .llseek = no_llseek,
- .write = stmp3xxx_wdt_write,
- .unlocked_ioctl = stmp3xxx_wdt_ioctl,
- .open = stmp3xxx_wdt_open,
- .release = stmp3xxx_wdt_release,
-};
-
-static struct miscdevice stmp3xxx_wdt_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &stmp3xxx_wdt_fops,
-};
-
-static int __devinit stmp3xxx_wdt_probe(struct platform_device *pdev)
-{
- int ret = 0;
-
- if (heartbeat < 1 || heartbeat > MAX_HEARTBEAT)
- heartbeat = DEFAULT_HEARTBEAT;
-
- boot_status = __raw_readl(REGS_RTC_BASE + HW_RTC_PERSISTENT1) &
- BV_RTC_PERSISTENT1_GENERAL__RTC_FORCE_UPDATER;
- boot_status = !!boot_status;
- stmp3xxx_clearl(BV_RTC_PERSISTENT1_GENERAL__RTC_FORCE_UPDATER,
- REGS_RTC_BASE + HW_RTC_PERSISTENT1);
- wdt_disable(); /* disable for now */
-
- ret = misc_register(&stmp3xxx_wdt_miscdev);
- if (ret < 0) {
- dev_err(&pdev->dev, "cannot register misc device\n");
- return ret;
- }
-
- printk(KERN_INFO "stmp3xxx watchdog: initialized, heartbeat %d sec\n",
- heartbeat);
-
- return ret;
-}
-
-static int __devexit stmp3xxx_wdt_remove(struct platform_device *pdev)
-{
- misc_deregister(&stmp3xxx_wdt_miscdev);
- return 0;
-}
-
-#ifdef CONFIG_PM
-static int wdt_suspended;
-static u32 wdt_saved_time;
-
-static int stmp3xxx_wdt_suspend(struct platform_device *pdev,
- pm_message_t state)
-{
- if (__raw_readl(REGS_RTC_BASE + HW_RTC_CTRL) &
- BM_RTC_CTRL_WATCHDOGEN) {
- wdt_suspended = 1;
- wdt_saved_time = __raw_readl(REGS_RTC_BASE + HW_RTC_WATCHDOG);
- wdt_disable();
- }
- return 0;
-}
-
-static int stmp3xxx_wdt_resume(struct platform_device *pdev)
-{
- if (wdt_suspended) {
- wdt_enable(wdt_saved_time);
- wdt_suspended = 0;
- }
- return 0;
-}
-#else
-#define stmp3xxx_wdt_suspend NULL
-#define stmp3xxx_wdt_resume NULL
-#endif
-
-static struct platform_driver platform_wdt_driver = {
- .driver = {
- .name = "stmp3xxx_wdt",
- },
- .probe = stmp3xxx_wdt_probe,
- .remove = __devexit_p(stmp3xxx_wdt_remove),
- .suspend = stmp3xxx_wdt_suspend,
- .resume = stmp3xxx_wdt_resume,
-};
-
-static int __init stmp3xxx_wdt_init(void)
-{
- return platform_driver_register(&platform_wdt_driver);
-}
-
-static void __exit stmp3xxx_wdt_exit(void)
-{
- return platform_driver_unregister(&platform_wdt_driver);
-}
-
-module_init(stmp3xxx_wdt_init);
-module_exit(stmp3xxx_wdt_exit);
-
-MODULE_DESCRIPTION("STMP3XXX Watchdog Driver");
-MODULE_LICENSE("GPL");
-
-module_param(heartbeat, int, 0);
-MODULE_PARM_DESC(heartbeat,
- "Watchdog heartbeat period in seconds from 1 to "
- __MODULE_STRING(MAX_HEARTBEAT) ", default "
- __MODULE_STRING(DEFAULT_HEARTBEAT));
-
-MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
--
1.7.7.3
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