[PATCH 0/3] improved watchdog driver for STMP3xyz/imx23/imx28

[PATCH 0/3] improved watchdog driver for STMP3xyz/imx23/imx28

[Wolfram Sang]

Geez, this should have been sent a year ago but it dropped off somehow.
Introduce a new user of the watchdog framework. This is a rewritten driver
for STMP and imx23/28: Quoting Patch 2/3 for the motivation of a rewrite:

===

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 and avoids open coding
the watchdog API again. It also uses now an explicitly 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 depends on a mach replaced
by another one a year ago. Since the user interface is still the
standard watchdog API, users don't need to adapt.

===

The first patch adds an accessor routine to the RTC-driver which can hopefully
go via the watchdog-tree as well (asking for Andrew's ack here). It is needed
because the old driver silently assumed its IO area to be already remapped by
the RTC driver. The second patch adds the new driver, the third removes the old
one. The old driver was broken (= not compilable, no arch for it) anyhow, so
there cannot be any regression. Based on 3.8-rc2 and tested on various MX28
boards.

Thanks,

   Wolfram


Wolfram Sang (3):
  rtc: stmp3xxx: add wdt-accessor function
  watchdog: add new driver for STMP3xxx and i.MX23/28
  watchdog: remove old STMP3xxx driver

 drivers/rtc/rtc-stmp3xxx.c          |   64 ++++++++
 drivers/watchdog/Kconfig            |   13 +-
 drivers/watchdog/Makefile           |    2 +-
 drivers/watchdog/stmp3xxx_rtc_wdt.c |  111 ++++++++++++++
 drivers/watchdog/stmp3xxx_wdt.c     |  288 -----------------------------------
 include/linux/stmp3xxx_rtc_wdt.h    |   15 ++
 6 files changed, 198 insertions(+), 295 deletions(-)
 create mode 100644 drivers/watchdog/stmp3xxx_rtc_wdt.c
 delete mode 100644 drivers/watchdog/stmp3xxx_wdt.c
 create mode 100644 include/linux/stmp3xxx_rtc_wdt.h

-- 
1.7.10.4

[PATCH 1/3] rtc: stmp3xxx: add wdt-accessor function

[Wolfram Sang]

This RTC also includes a watchdog timer. Provide an accessor function for
setting the watchdog timeout value which will be picked up by a watchdog
driver. Also register the platform_device for the watchdog here to get the
boot-time dependencies right. The watchdog driver will depend on this RTC
driver in Kconfig.

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
---

Change since last version:

* dynamically allocate the new platform device instead of a static one
* build fixes when watchdog is disabled

 drivers/rtc/rtc-stmp3xxx.c       |   64 ++++++++++++++++++++++++++++++++++++++
 include/linux/stmp3xxx_rtc_wdt.h |   15 +++++++++
 2 files changed, 79 insertions(+)
 create mode 100644 include/linux/stmp3xxx_rtc_wdt.h

diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c
index 739ef556..cc9a9b6 100644
--- a/drivers/rtc/rtc-stmp3xxx.c
+++ b/drivers/rtc/rtc-stmp3xxx.c
@@ -26,6 +26,8 @@
 #include <linux/rtc.h>
 #include <linux/slab.h>
 #include <linux/of_device.h>
+#include <linux/stmp_device.h>
+#include <linux/stmp3xxx_rtc_wdt.h>
 
 #include <mach/common.h>
 
@@ -35,6 +37,7 @@
 #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
@@ -44,6 +47,8 @@
 
 #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
@@ -51,12 +56,70 @@
 #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 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_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 void stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data)
 {
 	/*
@@ -232,6 +295,7 @@ 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 */
-- 
1.7.10.4

[PATCH 2/3] watchdog: add new driver for STMP3xxx and i.MX23/28

[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 and avoids open coding
the watchdog API again. It also uses now an explicitly 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 depends on a mach replaced
by another one a year ago. Since the user interface is still the
standard watchdog API, users don't need to adapt.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
---
 drivers/watchdog/Kconfig            |   10 ++++
 drivers/watchdog/Makefile           |    1 +
 drivers/watchdog/stmp3xxx_rtc_wdt.c |  111 +++++++++++++++++++++++++++++++++++
 3 files changed, 122 insertions(+)
 create mode 100644 drivers/watchdog/stmp3xxx_rtc_wdt.c

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 7f809fd..9f44ecf 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -325,6 +325,16 @@ 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 97bbdb3a..3111d38 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -49,6 +49,7 @@ 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..c97e98d
--- /dev/null
+++ b/drivers/watchdog/stmp3xxx_rtc_wdt.c
@@ -0,0 +1,111 @@
+/*
+ * Watchdog driver for the RTC based watchdog in STMP3xxx and i.MX23/28
+ *
+ * Author: Wolfram Sang <w.sang@pengutronix.de>
+ *
+ * Copyright (C) 2011-12 Wolfram Sang, Pengutronix
+ *
+ * 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 19
+#define STMP3XXX_MAX_TIMEOUT (UINT_MAX / WDOG_TICK_RATE)
+
+static int heartbeat = STMP3XXX_DEFAULT_TIMEOUT;
+module_param(heartbeat, uint, 0);
+MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat 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)
+{
+	wdd->timeout = new_timeout;
+	return wdt_start(wdd);
+}
+
+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 stmp3xxx_wdt_probe(struct platform_device *pdev)
+{
+	int ret;
+
+	watchdog_set_drvdata(&stmp3xxx_wdd, &pdev->dev);
+
+	stmp3xxx_wdd.timeout = clamp_t(unsigned, heartbeat, 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 heartbeat %ds\n",
+			stmp3xxx_wdd.timeout);
+	return 0;
+}
+
+static int stmp3xxx_wdt_remove(struct platform_device *pdev)
+{
+	watchdog_unregister_device(&stmp3xxx_wdd);
+	return 0;
+}
+
+static struct platform_driver stmp3xxx_wdt_driver = {
+	.driver = {
+		.name = "stmp3xxx_rtc_wdt",
+	},
+	.probe = stmp3xxx_wdt_probe,
+	.remove = 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);
-- 
1.7.10.4

[PATCH 3/3] watchdog: remove old STMP3xxx driver

[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 |  288 ---------------------------------------
 3 files changed, 298 deletions(-)
 delete mode 100644 drivers/watchdog/stmp3xxx_wdt.c

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 9f44ecf..f8dcb89 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -316,15 +316,6 @@ 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 3111d38..25120f8 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -48,7 +48,6 @@ 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 1f4f697..0000000
--- a/drivers/watchdog/stmp3xxx_wdt.c
+++ /dev/null
@@ -1,288 +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.
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#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 bool 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 unexpectedly\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 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;
-	}
-
-	pr_info("initialized, heartbeat %d sec\n", heartbeat);
-
-	return ret;
-}
-
-static int 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 = stmp3xxx_wdt_remove,
-	.suspend = stmp3xxx_wdt_suspend,
-	.resume = stmp3xxx_wdt_resume,
-};
-
-module_platform_driver(platform_wdt_driver);
-
-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);
-- 
1.7.10.4

Re: [PATCH 1/3] rtc: stmp3xxx: add wdt-accessor function

[Andrew Morton]

On Fri,  4 Jan 2013 14:58:47 +0100
Wolfram Sang <w.sang@pengutronix.de> wrote:

> This RTC also includes a watchdog timer. Provide an accessor function for
> setting the watchdog timeout value which will be picked up by a watchdog
> driver. Also register the platform_device for the watchdog here to get the
> boot-time dependencies right. The watchdog driver will depend on this RTC
> driver in Kconfig.

Patch looks OK, but I don't have patches 2-3 and nothing in my tree
enables CONFIG_STMP3XXX_RTC_WATCHDOG.

Wim, please merge this one with the other two if/when you take thenm,
thanks.

Re: [PATCH 0/3] improved watchdog driver for STMP3xyz/imx23/imx28

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 2650 bytes --]

On Fri, Jan 04, 2013 at 02:58:46PM +0100, Wolfram Sang wrote:
> Geez, this should have been sent a year ago but it dropped off somehow.
> Introduce a new user of the watchdog framework. This is a rewritten driver
> for STMP and imx23/28: Quoting Patch 2/3 for the motivation of a rewrite:
> 
> ===
> 
> 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 and avoids open coding
> the watchdog API again. It also uses now an explicitly 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 depends on a mach replaced
> by another one a year ago. Since the user interface is still the
> standard watchdog API, users don't need to adapt.
> 
> ===
> 
> The first patch adds an accessor routine to the RTC-driver which can hopefully
> go via the watchdog-tree as well (asking for Andrew's ack here). It is needed
> because the old driver silently assumed its IO area to be already remapped by
> the RTC driver. The second patch adds the new driver, the third removes the old
> one. The old driver was broken (= not compilable, no arch for it) anyhow, so
> there cannot be any regression. Based on 3.8-rc2 and tested on various MX28
> boards.
> 
> Thanks,
> 
>    Wolfram

Ping.

I rebased and tested the series against v3.8-rc5, added Andrew's ack and
pushed it out to

	git://git.pengutronix.de/git/wsa/linux.git watchdog_mxs

Would be awesome to have this (simple) driver in 3.9.

> 
> 
> Wolfram Sang (3):
>   rtc: stmp3xxx: add wdt-accessor function
>   watchdog: add new driver for STMP3xxx and i.MX23/28
>   watchdog: remove old STMP3xxx driver
> 
>  drivers/rtc/rtc-stmp3xxx.c          |   64 ++++++++
>  drivers/watchdog/Kconfig            |   13 +-
>  drivers/watchdog/Makefile           |    2 +-
>  drivers/watchdog/stmp3xxx_rtc_wdt.c |  111 ++++++++++++++
>  drivers/watchdog/stmp3xxx_wdt.c     |  288 -----------------------------------
>  include/linux/stmp3xxx_rtc_wdt.h    |   15 ++
>  6 files changed, 198 insertions(+), 295 deletions(-)
>  create mode 100644 drivers/watchdog/stmp3xxx_rtc_wdt.c
>  delete mode 100644 drivers/watchdog/stmp3xxx_wdt.c
>  create mode 100644 include/linux/stmp3xxx_rtc_wdt.h
> 
> -- 
> 1.7.10.4
> 

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 198 bytes --]

Re: [PATCH 0/3] improved watchdog driver for STMP3xyz/imx23/imx28

[Wim Van Sebroeck]

Hi Wolfram,

> On Fri, Jan 04, 2013 at 02:58:46PM +0100, Wolfram Sang wrote:
> > Geez, this should have been sent a year ago but it dropped off somehow.
> > Introduce a new user of the watchdog framework. This is a rewritten driver
> > for STMP and imx23/28: Quoting Patch 2/3 for the motivation of a rewrite:
> > 
> > ===
> > 
> > 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 and avoids open coding
> > the watchdog API again. It also uses now an explicitly 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 depends on a mach replaced
> > by another one a year ago. Since the user interface is still the
> > standard watchdog API, users don't need to adapt.
> > 
> > ===
> > 
> > The first patch adds an accessor routine to the RTC-driver which can hopefully
> > go via the watchdog-tree as well (asking for Andrew's ack here). It is needed
> > because the old driver silently assumed its IO area to be already remapped by
> > the RTC driver. The second patch adds the new driver, the third removes the old
> > one. The old driver was broken (= not compilable, no arch for it) anyhow, so
> > there cannot be any regression. Based on 3.8-rc2 and tested on various MX28
> > boards.
> > 
> > Thanks,
> > 
> >    Wolfram
> 
> Ping.
> 
> I rebased and tested the series against v3.8-rc5, added Andrew's ack and
> pushed it out to
> 
> 	git://git.pengutronix.de/git/wsa/linux.git watchdog_mxs
> 
> Would be awesome to have this (simple) driver in 3.9.
> 
> > 
> > 
> > Wolfram Sang (3):
> >   rtc: stmp3xxx: add wdt-accessor function
> >   watchdog: add new driver for STMP3xxx and i.MX23/28
> >   watchdog: remove old STMP3xxx driver
> > 
> >  drivers/rtc/rtc-stmp3xxx.c          |   64 ++++++++
> >  drivers/watchdog/Kconfig            |   13 +-
> >  drivers/watchdog/Makefile           |    2 +-
> >  drivers/watchdog/stmp3xxx_rtc_wdt.c |  111 ++++++++++++++
> >  drivers/watchdog/stmp3xxx_wdt.c     |  288 -----------------------------------
> >  include/linux/stmp3xxx_rtc_wdt.h    |   15 ++
> >  6 files changed, 198 insertions(+), 295 deletions(-)
> >  create mode 100644 drivers/watchdog/stmp3xxx_rtc_wdt.c
> >  delete mode 100644 drivers/watchdog/stmp3xxx_wdt.c
> >  create mode 100644 include/linux/stmp3xxx_rtc_wdt.h
> > 
> > -- 
> > 1.7.10.4
> > 
> 
> -- 
> Pengutronix e.K.                           | Wolfram Sang                |
> Industrial Linux Solutions                 | http://www.pengutronix.de/  |

Pulled it into linux-watchdog-next.

Kind regards,
Wim.

Re: [PATCH 0/3] improved watchdog driver for STMP3xyz/imx23/imx28

[Hector Palacios]

Dear Wolfram,

On 04/05/2013 06:17 PM, Palacios, Hector wrote:
> Geez, this should have been sent a year ago but it dropped off somehow.
> Introduce a new user of the watchdog framework. This is a rewritten driver
> for STMP and imx23/28: Quoting Patch 2/3 for the motivation of a rewrite:
>
> ===
>
> 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 and avoids open coding
> the watchdog API again. It also uses now an explicitly 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 depends on a mach replaced
> by another one a year ago. Since the user interface is still the
> standard watchdog API, users don't need to adapt.
>
> ===
>
> The first patch adds an accessor routine to the RTC-driver which can hopefully
> go via the watchdog-tree as well (asking for Andrew's ack here). It is needed
> because the old driver silently assumed its IO area to be already remapped by
> the RTC driver. The second patch adds the new driver, the third removes the old
> one. The old driver was broken (= not compilable, no arch for it) anyhow, so
> there cannot be any regression. Based on 3.8-rc2 and tested on various MX28
> boards.
>
> Thanks,
>
>      Wolfram
>
>
> Wolfram Sang (3):
>     rtc: stmp3xxx: add wdt-accessor function
>     watchdog: add new driver for STMP3xxx and i.MX23/28
>     watchdog: remove old STMP3xxx driver
>
>    drivers/rtc/rtc-stmp3xxx.c          |   64 ++++++++
>    drivers/watchdog/Kconfig            |   13 +-
>    drivers/watchdog/Makefile           |    2 +-
>    drivers/watchdog/stmp3xxx_rtc_wdt.c |  111 ++++++++++++++
>    drivers/watchdog/stmp3xxx_wdt.c     |  288 -----------------------------------
>    include/linux/stmp3xxx_rtc_wdt.h    |   15 ++
>    6 files changed, 198 insertions(+), 295 deletions(-)
>    create mode 100644 drivers/watchdog/stmp3xxx_rtc_wdt.c
>    delete mode 100644 drivers/watchdog/stmp3xxx_wdt.c
>    create mode 100644 include/linux/stmp3xxx_rtc_wdt.h

Thank you.

Reviewed-by: Hector Palacios <hector.palacios@digi.com>
Tested-by: Hector Palacios <hector.palacios@digi.com>