[PATCH 1/3] Watchdog: Omap: Changes for the new watchdog framework
Zumeng Chen
zumeng.chen at windriver.com
Mon Jul 9 00:39:37 EDT 2012
This patch implements the current watchdog framework for OMAP WDTimer,
which factored out the common components, so the driver can just focus
on the hardware related parts.
Signed-off-by: Zumeng Chen <zumeng.chen at windriver.com>
---
drivers/watchdog/omap_wdt.c | 338 ++++++++++++++++---------------------------
drivers/watchdog/omap_wdt.h | 5 +
2 files changed, 128 insertions(+), 215 deletions(-)
diff --git a/drivers/watchdog/omap_wdt.c b/drivers/watchdog/omap_wdt.c
index 8285d65..df9ed78 100644
--- a/drivers/watchdog/omap_wdt.c
+++ b/drivers/watchdog/omap_wdt.c
@@ -24,6 +24,9 @@
*
* Copyright (c) 2005 David Brownell
* Use the driver model and standard identifiers; handle bigger timeouts.
+ *
+ * Copyright (c) 2012 WindRiver
+ * Changes cater for the current watchdog framework.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
@@ -33,7 +36,6 @@
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/mm.h>
-#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/reboot.h>
#include <linux/init.h>
@@ -50,8 +52,6 @@
#include "omap_wdt.h"
-static struct platform_device *omap_wdt_dev;
-
static unsigned timer_margin;
module_param(timer_margin, uint, 0);
MODULE_PARM_DESC(timer_margin, "initial watchdog timeout (in seconds)");
@@ -59,32 +59,14 @@ MODULE_PARM_DESC(timer_margin, "initial watchdog timeout (in seconds)");
static unsigned int wdt_trgr_pattern = 0x1234;
static DEFINE_SPINLOCK(wdt_lock);
-struct omap_wdt_dev {
+struct omap_wdt_drvdata {
+ struct watchdog_device wdt;
void __iomem *base; /* physical */
struct device *dev;
- int omap_wdt_users;
struct resource *mem;
- struct miscdevice omap_wdt_miscdev;
};
-static void omap_wdt_ping(struct omap_wdt_dev *wdev)
-{
- void __iomem *base = wdev->base;
-
- /* wait for posted write to complete */
- while ((__raw_readl(base + OMAP_WATCHDOG_WPS)) & 0x08)
- cpu_relax();
-
- wdt_trgr_pattern = ~wdt_trgr_pattern;
- __raw_writel(wdt_trgr_pattern, (base + OMAP_WATCHDOG_TGR));
-
- /* wait for posted write to complete */
- while ((__raw_readl(base + OMAP_WATCHDOG_WPS)) & 0x08)
- cpu_relax();
- /* reloaded WCRR from WLDR */
-}
-
-static void omap_wdt_enable(struct omap_wdt_dev *wdev)
+static void omap_wdt_enable(struct omap_wdt_drvdata *wdev)
{
void __iomem *base = wdev->base;
@@ -98,7 +80,7 @@ static void omap_wdt_enable(struct omap_wdt_dev *wdev)
cpu_relax();
}
-static void omap_wdt_disable(struct omap_wdt_dev *wdev)
+static void omap_wdt_disable(struct omap_wdt_drvdata *wdev)
{
void __iomem *base = wdev->base;
@@ -121,12 +103,19 @@ static void omap_wdt_adjust_timeout(unsigned new_timeout)
timer_margin = new_timeout;
}
-static void omap_wdt_set_timeout(struct omap_wdt_dev *wdev)
+static int omap_wdt_set_timeout(struct watchdog_device *wdt_dev,
+ unsigned int new_timeout)
{
- u32 pre_margin = GET_WLDR_VAL(timer_margin);
- void __iomem *base = wdev->base;
+ u32 pre_margin;
+ struct omap_wdt_drvdata *omap_wdev = watchdog_get_drvdata(wdt_dev);
+ void __iomem *base = omap_wdev->base;
+
+ pm_runtime_get_sync(omap_wdev->dev);
+ omap_wdt_disable(omap_wdev);
- pm_runtime_get_sync(wdev->dev);
+ /* adjust timeout based on the new timeout */
+ omap_wdt_adjust_timeout(new_timeout);
+ pre_margin = GET_WLDR_VAL(timer_margin);
/* just count up at 32 KHz */
while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x04)
@@ -136,147 +125,87 @@ static void omap_wdt_set_timeout(struct omap_wdt_dev *wdev)
while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x04)
cpu_relax();
- pm_runtime_put_sync(wdev->dev);
+ pm_runtime_put_sync(omap_wdev->dev);
+ return 0;
}
-/*
- * Allow only one task to hold it open
- */
-static int omap_wdt_open(struct inode *inode, struct file *file)
+static int omap_wdt_ping(struct watchdog_device *wdt_dev)
{
- struct omap_wdt_dev *wdev = platform_get_drvdata(omap_wdt_dev);
- void __iomem *base = wdev->base;
-
- if (test_and_set_bit(1, (unsigned long *)&(wdev->omap_wdt_users)))
- return -EBUSY;
+ struct omap_wdt_drvdata *omap_wdev = watchdog_get_drvdata(wdt_dev);
+ void __iomem *base = omap_wdev->base;
- pm_runtime_get_sync(wdev->dev);
-
- /* initialize prescaler */
- while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x01)
- cpu_relax();
+ pm_runtime_get_sync(omap_wdev->dev);
+ spin_lock(&wdt_lock);
- __raw_writel((1 << 5) | (PTV << 2), base + OMAP_WATCHDOG_CNTRL);
- while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x01)
+ /* wait for posted write to complete */
+ while ((__raw_readl(base + OMAP_WATCHDOG_WPS)) & 0x08)
cpu_relax();
- file->private_data = (void *) wdev;
+ wdt_trgr_pattern = ~wdt_trgr_pattern;
+ __raw_writel(wdt_trgr_pattern, (base + OMAP_WATCHDOG_TGR));
- omap_wdt_set_timeout(wdev);
- omap_wdt_ping(wdev); /* trigger loading of new timeout value */
- omap_wdt_enable(wdev);
+ /* wait for posted write to complete */
+ /* reloaded WCRR from WLDR */
+ while ((__raw_readl(base + OMAP_WATCHDOG_WPS)) & 0x08)
+ cpu_relax();
- pm_runtime_put_sync(wdev->dev);
+ spin_unlock(&wdt_lock);
+ pm_runtime_put_sync(omap_wdev->dev);
- return nonseekable_open(inode, file);
+ return 0;
}
-static int omap_wdt_release(struct inode *inode, struct file *file)
+static int omap_wdt_start(struct watchdog_device *wdt_dev)
{
- struct omap_wdt_dev *wdev = file->private_data;
+ struct omap_wdt_drvdata *omap_wdev = watchdog_get_drvdata(wdt_dev);
+ void __iomem *base = omap_wdev->base;
- /*
- * Shut off the timer unless NOWAYOUT is defined.
- */
-#ifndef CONFIG_WATCHDOG_NOWAYOUT
- pm_runtime_get_sync(wdev->dev);
+ pm_runtime_get_sync(omap_wdev->dev);
+ /* initialize prescaler */
+ while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x01)
+ cpu_relax();
- omap_wdt_disable(wdev);
+ __raw_writel((1 << 5) | (PTV << 2), base + OMAP_WATCHDOG_CNTRL);
+ while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x01)
+ cpu_relax();
- pm_runtime_put_sync(wdev->dev);
-#else
- pr_crit("Unexpected close, not stopping!\n");
-#endif
- wdev->omap_wdt_users = 0;
+ omap_wdt_set_timeout(&omap_wdev->wdt, timer_margin);
+ omap_wdt_enable(omap_wdev);
+ pm_runtime_put_sync(omap_wdev->dev);
return 0;
}
-static ssize_t omap_wdt_write(struct file *file, const char __user *data,
- size_t len, loff_t *ppos)
+static int omap_wdt_stop(struct watchdog_device *wdt_dev)
{
- struct omap_wdt_dev *wdev = file->private_data;
-
- /* Refresh LOAD_TIME. */
- if (len) {
- pm_runtime_get_sync(wdev->dev);
- spin_lock(&wdt_lock);
- omap_wdt_ping(wdev);
- spin_unlock(&wdt_lock);
- pm_runtime_put_sync(wdev->dev);
- }
- return len;
-}
+ struct omap_wdt_drvdata *omap_wdev = watchdog_get_drvdata(wdt_dev);
-static long omap_wdt_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- struct omap_wdt_dev *wdev;
- int new_margin;
- static const struct watchdog_info ident = {
- .identity = "OMAP Watchdog",
- .options = WDIOF_SETTIMEOUT,
- .firmware_version = 0,
- };
-
- wdev = file->private_data;
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- return copy_to_user((struct watchdog_info __user *)arg, &ident,
- sizeof(ident));
- case WDIOC_GETSTATUS:
- return put_user(0, (int __user *)arg);
- case WDIOC_GETBOOTSTATUS:
- if (cpu_is_omap16xx())
- return put_user(__raw_readw(ARM_SYSST),
- (int __user *)arg);
- if (cpu_is_omap24xx())
- return put_user(omap_prcm_get_reset_sources(),
- (int __user *)arg);
- return put_user(0, (int __user *)arg);
- case WDIOC_KEEPALIVE:
- pm_runtime_get_sync(wdev->dev);
- spin_lock(&wdt_lock);
- omap_wdt_ping(wdev);
- spin_unlock(&wdt_lock);
- pm_runtime_put_sync(wdev->dev);
- return 0;
- case WDIOC_SETTIMEOUT:
- if (get_user(new_margin, (int __user *)arg))
- return -EFAULT;
- omap_wdt_adjust_timeout(new_margin);
-
- pm_runtime_get_sync(wdev->dev);
- spin_lock(&wdt_lock);
- omap_wdt_disable(wdev);
- omap_wdt_set_timeout(wdev);
- omap_wdt_enable(wdev);
-
- omap_wdt_ping(wdev);
- spin_unlock(&wdt_lock);
- pm_runtime_put_sync(wdev->dev);
- /* Fall */
- case WDIOC_GETTIMEOUT:
- return put_user(timer_margin, (int __user *)arg);
- default:
- return -ENOTTY;
- }
+ pm_runtime_get_sync(omap_wdev->dev);
+ omap_wdt_disable(omap_wdev);
+ pm_runtime_put_sync(omap_wdev->dev);
+
+ return 0;
}
-static const struct file_operations omap_wdt_fops = {
+static const struct watchdog_ops omap_wdt_ops = {
.owner = THIS_MODULE,
- .write = omap_wdt_write,
- .unlocked_ioctl = omap_wdt_ioctl,
- .open = omap_wdt_open,
- .release = omap_wdt_release,
- .llseek = no_llseek,
+ .start = omap_wdt_start,
+ .stop = omap_wdt_stop,
+ .ping = omap_wdt_ping,
+ .set_timeout = omap_wdt_set_timeout,
+};
+
+static const struct watchdog_info omap_wdt_info = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING |
+ WDIOF_CARDRESET,
+ .identity = "Omap Watchdog",
};
static int __devinit omap_wdt_probe(struct platform_device *pdev)
{
+ struct omap_wdt_drvdata *omap_drvdata;
+ struct watchdog_device *omap_wdev;
struct resource *res, *mem;
- struct omap_wdt_dev *wdev;
int ret;
/* reserve static register mappings */
@@ -286,68 +215,65 @@ static int __devinit omap_wdt_probe(struct platform_device *pdev)
goto err_get_resource;
}
- if (omap_wdt_dev) {
- ret = -EBUSY;
- goto err_busy;
- }
-
mem = request_mem_region(res->start, resource_size(res), pdev->name);
if (!mem) {
ret = -EBUSY;
goto err_busy;
}
- wdev = kzalloc(sizeof(struct omap_wdt_dev), GFP_KERNEL);
- if (!wdev) {
+ omap_drvdata = devm_kzalloc(&pdev->dev, sizeof(struct omap_wdt_drvdata),
+ GFP_KERNEL);
+ if (!omap_drvdata) {
+ dev_err(&pdev->dev, "Unable to alloacate watchdog device\n");
ret = -ENOMEM;
goto err_kzalloc;
}
- wdev->omap_wdt_users = 0;
- wdev->mem = mem;
- wdev->dev = &pdev->dev;
+ omap_drvdata->dev = &pdev->dev;
+ omap_wdev = &omap_drvdata->wdt;
+ omap_wdev->info = &omap_wdt_info;
+ omap_wdev->ops = &omap_wdt_ops;
+ omap_wdev->timeout = TIMER_MARGIN_DEFAULT;
+ omap_wdev->min_timeout = 1;
+ omap_wdev->max_timeout = TIMER_MARGIN_MAX;
+#ifdef CONFIG_WATCHDOG_NOWAYOUT
+ watchdog_set_nowayout(omap_wdev, true);
+#endif
+ watchdog_set_drvdata(omap_wdev, omap_drvdata);
- wdev->base = ioremap(res->start, resource_size(res));
- if (!wdev->base) {
+ omap_drvdata->base = ioremap(res->start, resource_size(res));
+ if (!omap_drvdata->base) {
ret = -ENOMEM;
goto err_ioremap;
}
- platform_set_drvdata(pdev, wdev);
-
- pm_runtime_enable(wdev->dev);
- pm_runtime_get_sync(wdev->dev);
-
- omap_wdt_disable(wdev);
- omap_wdt_adjust_timeout(timer_margin);
-
- wdev->omap_wdt_miscdev.parent = &pdev->dev;
- wdev->omap_wdt_miscdev.minor = WATCHDOG_MINOR;
- wdev->omap_wdt_miscdev.name = "watchdog";
- wdev->omap_wdt_miscdev.fops = &omap_wdt_fops;
-
- ret = misc_register(&(wdev->omap_wdt_miscdev));
- if (ret)
- goto err_misc;
-
- pr_info("OMAP Watchdog Timer Rev 0x%02x: initial timeout %d sec\n",
- __raw_readl(wdev->base + OMAP_WATCHDOG_REV) & 0xFF,
- timer_margin);
-
- pm_runtime_put_sync(wdev->dev);
-
- omap_wdt_dev = pdev;
+ ret = watchdog_register_device(&omap_drvdata->wdt);
+ if (ret < 0)
+ goto err_register_wd;
+
+ pm_runtime_enable(&pdev->dev);
+ pm_runtime_get_sync(&pdev->dev);
+ omap_wdt_disable(omap_drvdata);
+ pm_runtime_put_sync(&pdev->dev);
+ platform_set_drvdata(pdev, omap_drvdata);
+
+ /* For omap16xx we just keep it original as-is */
+ if (cpu_is_omap16xx())
+ omap_wdev->bootstatus = __raw_readw(ARM_SYSST);
+ else
+ omap_wdev->bootstatus = (omap_prcm_get_reset_sources() & 0x10)
+ >> OMAP3_PRM_RSTST_WD_BIT;
+ pr_info("OMAP WDTimer Rev 0x%02x: Initial timeout %dsec status= 0x%x\n",
+ __raw_readl(omap_drvdata->base + OMAP_WATCHDOG_REV)
+ & 0xFF, timer_margin, omap_wdev->bootstatus);
return 0;
-err_misc:
- pm_runtime_disable(wdev->dev);
- platform_set_drvdata(pdev, NULL);
- iounmap(wdev->base);
+err_register_wd:
+ iounmap(omap_drvdata->base);
err_ioremap:
- wdev->base = NULL;
- kfree(wdev);
+ kfree(omap_drvdata);
err_kzalloc:
release_mem_region(res->start, resource_size(res));
@@ -358,34 +284,19 @@ err_get_resource:
return ret;
}
-static void omap_wdt_shutdown(struct platform_device *pdev)
-{
- struct omap_wdt_dev *wdev = platform_get_drvdata(pdev);
-
- if (wdev->omap_wdt_users) {
- pm_runtime_get_sync(wdev->dev);
- omap_wdt_disable(wdev);
- pm_runtime_put_sync(wdev->dev);
- }
-}
-
static int __devexit omap_wdt_remove(struct platform_device *pdev)
{
- struct omap_wdt_dev *wdev = platform_get_drvdata(pdev);
+ struct omap_wdt_drvdata *omap_wdev = platform_get_drvdata(pdev);
struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- pm_runtime_disable(wdev->dev);
- if (!res)
- return -ENOENT;
+ pm_runtime_disable(&pdev->dev);
- misc_deregister(&(wdev->omap_wdt_miscdev));
release_mem_region(res->start, resource_size(res));
platform_set_drvdata(pdev, NULL);
- iounmap(wdev->base);
+ iounmap(omap_wdev->base);
- kfree(wdev);
- omap_wdt_dev = NULL;
+ kfree(omap_wdev);
return 0;
}
@@ -400,12 +311,12 @@ static int __devexit omap_wdt_remove(struct platform_device *pdev)
static int omap_wdt_suspend(struct platform_device *pdev, pm_message_t state)
{
- struct omap_wdt_dev *wdev = platform_get_drvdata(pdev);
+ struct omap_wdt_drvdata *omap_wdev = platform_get_drvdata(pdev);
- if (wdev->omap_wdt_users) {
- pm_runtime_get_sync(wdev->dev);
- omap_wdt_disable(wdev);
- pm_runtime_put_sync(wdev->dev);
+ if (test_bit(WDOG_DEV_OPEN, &omap_wdev->wdt.status)) {
+ pm_runtime_get_sync(&pdev->dev);
+ omap_wdt_disable(omap_wdev);
+ pm_runtime_put_sync(&pdev->dev);
}
return 0;
@@ -413,13 +324,12 @@ static int omap_wdt_suspend(struct platform_device *pdev, pm_message_t state)
static int omap_wdt_resume(struct platform_device *pdev)
{
- struct omap_wdt_dev *wdev = platform_get_drvdata(pdev);
-
- if (wdev->omap_wdt_users) {
- pm_runtime_get_sync(wdev->dev);
- omap_wdt_enable(wdev);
- omap_wdt_ping(wdev);
- pm_runtime_put_sync(wdev->dev);
+ struct omap_wdt_drvdata *omap_wdev = platform_get_drvdata(pdev);
+ if (test_bit(WDOG_DEV_OPEN, &omap_wdev->wdt.status)) {
+ pm_runtime_get_sync(&pdev->dev);
+ omap_wdt_enable(omap_wdev);
+ omap_wdt_ping(&omap_wdev->wdt);
+ pm_runtime_put_sync(&pdev->dev);
}
return 0;
@@ -433,7 +343,6 @@ static int omap_wdt_resume(struct platform_device *pdev)
static struct platform_driver omap_wdt_driver = {
.probe = omap_wdt_probe,
.remove = __devexit_p(omap_wdt_remove),
- .shutdown = omap_wdt_shutdown,
.suspend = omap_wdt_suspend,
.resume = omap_wdt_resume,
.driver = {
@@ -446,5 +355,4 @@ module_platform_driver(omap_wdt_driver);
MODULE_AUTHOR("George G. Davis");
MODULE_LICENSE("GPL");
-MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
MODULE_ALIAS("platform:omap_wdt");
diff --git a/drivers/watchdog/omap_wdt.h b/drivers/watchdog/omap_wdt.h
index 09b774c..cf5f037 100644
--- a/drivers/watchdog/omap_wdt.h
+++ b/drivers/watchdog/omap_wdt.h
@@ -51,4 +51,9 @@
#define PTV 0 /* prescale */
#define GET_WLDR_VAL(secs) (0xffffffff - ((secs) * (32768/(1<<PTV))) + 1)
+/* MPU_WD_RST bit in PRM_RSTST show Omap WDTimer reset event.
+ * 0x0 = 0x0 : No watchdog reset.
+ * 0x1 = 0x1 : watchdog reset has occurred. */
+#define OMAP3_PRM_RSTST_WD_BIT 4
+
#endif /* _OMAP_WATCHDOG_H */
--
1.7.5.4
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