/*
* linux/drivers/char/omap1610_wdt.c
*
- * Watchdog driver for the TI OMAP
+ * Watchdog driver for the TI OMAP 16xx 32KHz (non-secure) watchdog
*
* Author: MontaVista Software, Inc.
* <gdavis@mvista.com> or <source@mvista.com>
* Based on SoftDog driver by Alan Cox <alan@redhat.com>
*
* Copyright (c) 2004 Texas Instruments.
- *
- * 1. Modified to support OMAP1610 32-KHz watchdog timer
- * 2. Ported to 2.6 kernel
- *
- *
- * TODO:
- * 1. Need to disable watchdog when entering chip idle mode.
+ * 1. Modified to support OMAP1610 32-KHz watchdog timer
+ * 2. Ported to 2.6 kernel
*/
#include <linux/module.h>
#include <linux/smp_lock.h>
#include <linux/init.h>
#include <linux/err.h>
+#include <linux/moduleparam.h>
+
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/hardware.h>
#include <asm/bitops.h>
#include <asm/hardware/clock.h>
-#include <linux/moduleparam.h>
#include "omap1610_wdt.h"
-static int timer_margin; /* in seconds */
-static int pre_margin;
+
+static unsigned timer_margin;
+module_param(timer_margin, uint, 0);
+MODULE_PARM_DESC(timer_margin, "initial watchdog timeout (in seconds)");
+
static int omap_wdt_users;
-static struct clk *armwdt_ck = 0;
-static struct miscdevice omap_wdt_miscdev; /* Forward declaration */
+static struct clk *armwdt_ck = NULL;
static unsigned int wdt_trgr_pattern = 0x1234;
wdt_trgr_pattern = ~wdt_trgr_pattern;
omap_writel(wdt_trgr_pattern, (OMAP_WATCHDOG_TGR));
while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x08) ; /* wait for posted write to complete */
- return;
+ /* reloaded WCRR from WLDR */
}
static void
while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x10) ;
omap_writel(0x4444, OMAP_WATCHDOG_SPR);
while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x10) ;
- return;
}
static void
while (omap_readl(OMAP_WATCHDOG_WPS) & 0x10) ;
omap_writel(0x5555, OMAP_WATCHDOG_SPR); /* TIMER_MODE */
while (omap_readl(OMAP_WATCHDOG_WPS) & 0x10) ;
- return;
}
+static void
+omap_wdt_adjust_timeout(unsigned new_timeout)
+{
+ if (new_timeout < TIMER_MARGIN_MIN)
+ new_timeout = TIMER_MARGIN_DEFAULT;
+ if (new_timeout > TIMER_MARGIN_MAX)
+ new_timeout = TIMER_MARGIN_MAX;
+ timer_margin = new_timeout;
+}
+
+static void
+omap_wdt_set_timeout(void)
+{
+ u32 pre_margin = GET_WLDR_VAL(timer_margin);
+
+ /* just count up at 32 KHz */
+ while (omap_readl(OMAP_WATCHDOG_WPS) & 0x04) continue;
+ omap_writel(pre_margin, OMAP_WATCHDOG_LDR);
+ while (omap_readl(OMAP_WATCHDOG_WPS) & 0x04) continue;
+}
+
+
/*
- * Allow only one person to hold it open
+ * Allow only one task to hold it open
*/
static int
if (test_and_set_bit(1, (unsigned long *) &omap_wdt_users))
return -EBUSY;
- if (armwdt_ck == 0 || IS_ERR(armwdt_ck)) {
- armwdt_ck = clk_get(omap_wdt_miscdev.dev, "armwdt_ck");
- if (IS_ERR(armwdt_ck)) {
- omap_wdt_users = 0;
- return PTR_ERR(armwdt_ck);
- }
- clk_use(armwdt_ck); /* Enable the clock */
- }
+ clk_use(armwdt_ck); /* Enable the clock */
- omap_wdt_enable();
+ /* initialize prescaler */
+ while (omap_readl(OMAP_WATCHDOG_WPS) & 0x01) continue;
+ omap_writel((1 << 5) | (PTV << 2), OMAP_WATCHDOG_CNTRL);
+ while (omap_readl(OMAP_WATCHDOG_WPS) & 0x01) continue;
+ omap_wdt_set_timeout();
+ omap_wdt_enable();
return 0;
}
omap_wdt_release(struct inode *inode, struct file *file)
{
/*
- * Shut off the timer.
- * Lock it in if it's a module and we defined ...NOWAYOUT
+ * Shut off the timer unless NOWAYOUT is defined.
*/
#ifndef CONFIG_WATCHDOG_NOWAYOUT
omap_wdt_disable();
clk_unuse(armwdt_ck); /* Disable the clock */
clk_put(armwdt_ck);
- armwdt_ck = 0;
+ armwdt_ck = NULL;
+#else
+ printk(KERN_CRIT "omap1610_wdt: Unexpected close, not stopping!\n");
#endif
omap_wdt_users = 0;
return 0;
}
static ssize_t
-omap_wdt_write(struct file *file, const char *data, size_t len, loff_t * ppos)
+omap_wdt_write(struct file *file, const char __user *data,
+ size_t len, loff_t * ppos)
{
- /* Can't seek (pwrite) on this device */
- if (ppos != &file->f_pos)
- return -ESPIPE;
-
/* Refresh LOAD_TIME. */
- if (len) {
+ if (len)
omap_wdt_ping();
- return 1;
- }
- return 0;
+ return len;
}
static int
default:
return -ENOIOCTLCMD;
case WDIOC_GETSUPPORT:
- return copy_to_user((struct watchdog_info *) arg, &ident,
+ return copy_to_user((struct watchdog_info __user *) arg, &ident,
sizeof (ident));
case WDIOC_GETSTATUS:
- return put_user(0, (int *) arg);
+ return put_user(0, (int __user *) arg);
case WDIOC_GETBOOTSTATUS:
- return put_user(omap_readw(ARM_SYSST), (int *) arg);
+ return put_user(omap_readw(ARM_SYSST), (int __user *) arg);
case WDIOC_KEEPALIVE:
omap_wdt_ping();
return 0;
case WDIOC_SETTIMEOUT:
- if (get_user(new_margin, (int *) arg))
+ if (get_user(new_margin, (int __user *) arg))
return -EFAULT;
- if ((new_margin < TIMER_MARGIN_MIN)
- || (new_margin > TIMER_MARGIN_MAX))
- timer_margin = TIMER_MARGIN_MAX; /* default timeout */
- else
- timer_margin = new_margin;
- pre_margin = GET_WLDR_VAL(timer_margin);
+ omap_wdt_adjust_timeout(new_margin);
omap_wdt_disable();
-
- while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x04) ; /* wait for posted write to complete */
- omap_writel(pre_margin, (OMAP_WATCHDOG_LDR));
- while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x04) ; /* wait for posted write to complete */
-
+ omap_wdt_set_timeout();
omap_wdt_enable();
omap_wdt_ping();
/* Fall */
case WDIOC_GETTIMEOUT:
- return put_user(timer_margin, (int *) arg);
+ return put_user(timer_margin, (int __user *) arg);
}
}
static struct file_operations omap_wdt_fops = {
- .owner = THIS_MODULE,
- .write = omap_wdt_write,
- .ioctl = omap_wdt_ioctl,
- .open = omap_wdt_open,
- .release = omap_wdt_release,
+ .owner = THIS_MODULE,
+ .write = omap_wdt_write,
+ .ioctl = omap_wdt_ioctl,
+ .open = omap_wdt_open,
+ .release = omap_wdt_release,
};
static struct miscdevice omap_wdt_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "omap_wdt",
- .fops = &omap_wdt_fops
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &omap_wdt_fops
};
static int __init
{
int ret;
- ret = misc_register(&omap_wdt_miscdev);
-
- if (ret)
- return ret;
+ omap_wdt_users = 0;
+ armwdt_ck = clk_get(NULL, "armwdt_ck");
+ if (IS_ERR(armwdt_ck)) {
+ ret = PTR_ERR(armwdt_ck);
+ armwdt_ck = NULL;
+ goto fail;
+ }
omap_wdt_disable();
+ omap_wdt_adjust_timeout(timer_margin);
- if (timer_margin < 1 || timer_margin > 32)
- timer_margin = 32;
+ ret = misc_register(&omap_wdt_miscdev);
+ if (ret)
+ goto fail;
- printk(KERN_INFO "%s: TI OMAP Watchdog Timer: timer margin %d sec\n",
- omap_wdt_miscdev.name, timer_margin);
+ pr_info("OMAP Watchdog Timer: initial timeout %d sec\n", timer_margin);
+ /* autogate OCP interface clock */
+ omap_writel(0x01, OMAP_WATCHDOG_SYS_CONFIG);
return 0;
+
+fail:
+ if (armwdt_ck)
+ clk_put(armwdt_ck);
+ return ret;
}
static void __exit
omap_wdt_exit(void)
{
misc_deregister(&omap_wdt_miscdev);
+ clk_put(armwdt_ck);
}
module_init(omap_wdt_init);
MODULE_AUTHOR("George G. Davis");
MODULE_LICENSE("GPL");
-module_param(timer_margin, int, 0);
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
projects / linux-2.6-omap-h63xx.git / commitdiff