Re: [2.4] Watchdog w83977ef (Winbond W83977EF) driver
From: Tal Kelrich
Date: Tue Apr 10 2007 - 08:02:44 EST
On Mon, 2 Apr 2007 07:38:34 +0200
Willy Tarreau <w@xxxxxx> wrote:
> Hello,
>
> On Sun, Apr 01, 2007 at 05:14:07PM +0300, Tal Kelrich wrote:
> > (resent due to mailer stupidity)
> > Hello,
> >
> > This is my first submitted kernel patch, please be gentle.
> >
> > Tested and working on AAEON GENE-6310B Subcompact Board
> > (also configured for same by default, should work elsewhere)
> > patch is against kernel 2.4.34.2
> >
> > Changes/Features:
> >
> > Added ioctl support
> > Disables watchdog on driver load
> > Supports timeout in seconds
> > Timeout defaults to 2 minutes
> > No longer under NetWinder arch
> > Configurable output GP (defaults to GP16)
> > Configurable base IO address
> > Non standard read only proc interface for status (/proc/watchdog)
> >
> > Caveats:
> >
> > No idea if this breaks netwinder, although it really shouldn't
> > Only tested with GP16
> > Utterly ignores inability to get its IO port, mostly because it's
> > already taken. I didn't know a way around that.
> > release_region is called regardless of having acquired the region,
> > this might be trouble.
>
> While I have no particular problem merging your other driver since it
> did not previously exist, I don't like much this one being massively
> changed like this, particularly when you cannot test whether it breaks
> its original platform (netwinder). I've also noticed that your patch
> removes some locking, so I'm even doubting that it will not break
> NetWinder.
>
> A less risky solution would be to make a new driver of it (eg:
> w93977.c instead of wdt977.c). Also, if you proceed like this, please
> do not forget to write an entry in Configure.help.
>
> Regards,
> Willy
>
Updated with your comments in mind,
now a seperate driver, added info to Configure.help
Regards,
Tal Kelrich
--
Tal Kelrich
PGP fingerprint: 3EDF FCC5 60BB 4729 AB2F CAE6 FEC1 9AAC 12B9 AA69
Key Available at: http://www.hasturkun.com/pub.txt
----
"I'm a mean green mother from outer space"
-- Audrey II, The Little Shop of Horrors
----
--- linux-2.4.34.2/Documentation/Configure.help Sat Mar 24 08:44:54 2007
+++ linux-2.4.34.2-w83977ef/Documentation/Configure.help Tue Apr 10 13:30:30 2007
@@ -20559,6 +20559,13 @@
computer, say `Y' here to support its built-in watchdog timer
feature. See the help for CONFIG_WATCHDOG for discussion.
+Winbond W83977EF Watchdog Timer
+CONFIG_W83977EF_WDT
+ This is a driver for the hardware watchdog on the W83977EF chipset.
+ To compile this driver as a module say M here. The module will be
+ named wdt83977.o
+ Most people will say N.
+
ALi M7101 Watchdog Timer
CONFIG_ALIM7101_WDT
This is the driver for the hardware watchdog on the ALi M7101 PMU
--- linux-2.4.34.2/drivers/char/Config.in Sat Mar 24 08:44:54 2007
+++ linux-2.4.34.2-w83977ef/drivers/char/Config.in Tue Apr 10 13:30:31 2007
@@ -276,6 +276,7 @@
if [ "$CONFIG_8xx" = "y" ]; then
tristate ' MPC8xx Watchdog Timer' CONFIG_8xx_WDT
fi
+ tristate ' Winbond W83977EF Watchdog Timer' CONFIG_W83977EF_WDT
fi
endmenu
--- linux-2.4.34.2/drivers/char/Makefile Sat Mar 24 08:44:54 2007
+++ linux-2.4.34.2-w83977ef/drivers/char/Makefile Tue Apr 10 13:30:31 2007
@@ -323,6 +323,7 @@
obj-$(CONFIG_SOFT_WATCHDOG) += softdog.o
obj-$(CONFIG_INDYDOG) += indydog.o
obj-$(CONFIG_8xx_WDT) += mpc8xx_wdt.o
+obj-$(CONFIG_W83977EF_WDT) += wdt83977.o
subdir-$(CONFIG_MWAVE) += mwave
ifeq ($(CONFIG_MWAVE),y)
--- linux-2.4.34.2/drivers/char/wdt83977.c Thu Jan 1 02:00:00 1970
+++ linux-2.4.34.2-w83977ef/drivers/char/wdt83977.c Tue Apr 10 13:30:31 2007
@@ -0,0 +1,350 @@
+/*
+ * Wdt83977 0.03: A Watchdog Device for Winbond W83977EF chip
+ * (c) Copyright 2007 Orpak Systems Ltd. (Tal Kelrich <tal@xxxxxxxxx>)
+ * based on wdt977 driver by Woody Suwalski <woody@xxxxxxxxxxxxx>
+ *
+ * (c) Copyright 1998 Rebel.com (Woody Suwalski <woody@xxxxxxxxxxxxx>)
+ *
+ * -----------------------
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/init.h>
+#include <linux/smp_lock.h>
+#include <linux/ioport.h>
+#include <linux/spinlock.h>
+#include <linux/watchdog.h>
+#include <linux/proc_fs.h>
+
+#include <asm/io.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/page.h>
+
+#define WATCHDOG_MINOR 130
+
+static int timeout = 120;
+static int timer_alive;
+static int expect_close = 0;
+static spinlock_t wdt_lock;
+
+/* port is either 0X370 or 0x3F0. there's probably no way to detect this */
+static int wdt_io = 0x370;
+
+#ifdef CONFIG_WATCHDOG_NOWAYOUT
+static int nowayout = 1;
+#else
+static int nowayout = 0;
+#endif
+
+static int whichgp = 16;
+
+MODULE_PARM(wdt_io,"i");
+MODULE_PARM_DESC(wdt_io,"WDT io port base (0x370/0x3F0)");
+
+MODULE_PARM(whichgp,"i");
+MODULE_PARM_DESC(whichgp,"which gp? (12/13/16)");
+
+MODULE_PARM(timeout,"i");
+
+MODULE_PARM(nowayout,"i");
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
+
+#define WDT_EFER (wdt_io+0) /* Extended Function Enable Registers */
+#define WDT_EFIR (wdt_io+0) /* Extended Function Index Register (same as EFER) */
+#define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */
+
+#define WDT_OUT(reg,data) {outb_p(reg,WDT_EFIR);outb_p(data,WDT_EFDR);}
+#define WDT_IN(reg,out) {outb_p(reg,WDT_EFIR);out=inb_p(WDT_EFDR);}
+#define WDT_DEV(device) {WDT_OUT(0x07,device);}
+#define WDT_ENABLE {outb_p(0x87,WDT_EFER);outb_p(0x87,WDT_EFER);}
+#define WDT_DISABLE {outb_p(0xAA,WDT_EFER);}
+
+static int wdt977_readproc(char *page, char **start, off_t off, int count,
+ int *eof, void *data)
+{
+ int len;
+ unsigned char remaining;
+ unsigned char fired;
+ spin_lock(&wdt_lock);
+ WDT_ENABLE;
+ WDT_DEV(0x08);
+ WDT_IN(0xF2,remaining); /* get remaining time */
+ WDT_IN(0xF4,fired); /* and some nice status bits */
+ /* and clear the bit we care about */
+ WDT_OUT(0xF4,fired&(~0x01));
+ WDT_DISABLE;
+ spin_unlock(&wdt_lock);
+ fired=fired & 0x01;
+ len=snprintf(page,PAGE_SIZE,
+ "W83977EF device\n"
+ "active=%d\n"
+ "iobase=%0X\n"
+ "gp=%d\n"
+ "nowayout=%d\n"
+ "timeout=%d\n"
+ "remaining=%d\n"
+ "fired=%d\n",
+ timer_alive,wdt_io,whichgp,nowayout,timeout,remaining,fired);
+ *eof=1;
+ return len;
+}
+
+static void wdt977_ctrl(int timeout)
+{
+ unsigned char status;
+ spin_lock(&wdt_lock);
+ WDT_ENABLE;
+ WDT_DEV(0x08);
+ WDT_OUT(0x30,0x01); /* enable */
+ WDT_OUT(0xF2,timeout);
+ WDT_IN(0xF4, status); /* so we don't set bit 0 */
+ WDT_OUT(0xF4,(status&0x01)|0x40); /* and seconds! */
+ WDT_DISABLE;
+ spin_unlock(&wdt_lock);
+}
+
+/*
+ * Allow only one person to hold it open
+ */
+
+static int wdt977_open(struct inode *inode, struct file *file)
+{
+ if(timer_alive)
+ return -EBUSY;
+ if (nowayout) {
+ MOD_INC_USE_COUNT;
+ }
+ timer_alive++;
+
+ //max timeout value = 255 minutes (0xFF). Write 0 to disable WatchDog.
+ if (timeout>255 || timeout <1)
+ timeout = 255;
+
+ printk(KERN_INFO "Watchdog: active, current timeout %d min.\n",timeout);
+
+ wdt977_ctrl(timeout);
+ return 0;
+}
+
+static int wdt977_release(struct inode *inode, struct file *file)
+{
+ /*
+ * Shut off the timer.
+ * Lock it in if it's a module and we set nowayout
+ */
+ if (expect_close) {
+ wdt977_ctrl(0); /* disable timer */
+ printk(KERN_INFO "Watchdog: shutdown.\n");
+ } else {
+ printk(KERN_CRIT "WDT device closed unexpectedly. WDT will not stop!\n");
+ }
+
+ timer_alive=0;
+
+ return 0;
+}
+
+static ssize_t wdt977_write(struct file *file, const char *data, size_t len, loff_t *ppos)
+{
+ /* Can't seek (pwrite) on this device */
+ if (ppos != &file->f_pos)
+ return -ESPIPE;
+ if (!nowayout) {
+ size_t i;
+
+ /* In case it was set long ago */
+ expect_close = 0;
+
+ for (i = 0; i != len; i++) {
+ char c;
+ if (get_user(c, data + i))
+ return -EFAULT;
+ if (c == 'V')
+ expect_close = 1;
+ }
+ }
+
+ //max timeout value = 255 minutes (0xFF). Write 0 to disable WatchDog.
+ if (timeout>255)
+ timeout = 255;
+
+ /*
+ * Refresh the timer.
+ */
+
+ wdt977_ctrl(timeout);
+
+ return 1;
+}
+
+static int wdt977_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ int new_timeout;
+ static struct watchdog_info ident = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
+ .firmware_version = 1,
+ .identity = "WDT83977 WDT",
+ };
+ void *argp = (void *)arg;
+ int *p = argp;
+ switch (cmd)
+ {
+ case WDIOC_GETSUPPORT:
+ if(copy_to_user(argp, &ident, sizeof(ident)))
+ return -EFAULT;
+ break;
+
+ case WDIOC_GETSTATUS:
+ return put_user(timer_alive, p);
+
+ case WDIOC_KEEPALIVE:
+ wdt977_ctrl(timeout);
+
+ case WDIOC_SETTIMEOUT:
+ if(get_user(new_timeout, p))
+ return -EFAULT;
+ if(new_timeout>255 || new_timeout < 1)
+ return -EINVAL;
+ timeout=new_timeout;
+ wdt977_ctrl(timeout);
+ /* FALLTHROUGH */
+
+ case WDIOC_GETTIMEOUT:
+ return put_user(timeout,p);
+
+ case WDIOC_SETOPTIONS:
+ {
+ int options, retval = -EINVAL;
+ if(get_user(options, p))
+ return -EFAULT;
+
+ if(options & WDIOS_DISABLECARD)
+ {
+ wdt977_ctrl(0);
+ retval = 0;
+ }
+ if(options & WDIOS_ENABLECARD)
+ {
+ wdt977_ctrl(timeout);
+ retval = 0;
+ }
+ return retval;
+ }
+ default:
+ return -ENOTTY;
+ }
+ return 0;
+}
+
+static struct file_operations wdt977_fops=
+{
+ owner: THIS_MODULE,
+ write: wdt977_write,
+ open: wdt977_open,
+ release: wdt977_release,
+ ioctl: wdt977_ioctl,
+};
+
+static struct miscdevice wdt977_miscdev=
+{
+ WATCHDOG_MINOR,
+ "watchdog",
+ &wdt977_fops
+};
+
+static int __init nwwatchdog_init(void)
+{
+ unsigned char status;
+ int ret;
+ spin_lock_init(&wdt_lock);
+ ret = misc_register(&wdt977_miscdev);
+ if(ret != 0)
+ goto out;
+ if(!request_region(wdt_io, 1, "W83977EF"))
+ {
+ /* Failure to get region is because on the board I was working on, wdt_io is
+ * consistently in use. there's probably a better solution to this */
+ printk(KERN_WARNING "W83977EF: IO address %04X already in use, continuing anyway\n",wdt_io);
+ }
+ if(!create_proc_read_entry("watchdog",0,NULL,&wdt977_readproc,NULL))
+ goto unreg_misc;
+ WDT_ENABLE;
+ /* select dev 7 */
+ WDT_DEV(0x07);
+ /* activate it */
+ WDT_OUT(0x30,0x01);
+ switch(whichgp)
+ {
+ case 12:
+ ret=0xE2;
+ break;
+ case 13:
+ ret=0xE3;
+ break;
+ default:
+ whichgp=16;
+ case 16:
+ ret=0xE6;
+ break;
+ }
+ WDT_OUT(ret,0x0A);
+ /* select dev 8 */
+ WDT_DEV(0x08);
+ /* enable it */
+ WDT_OUT(0x30,0x01);
+ /* power led cycle on wdog timeout */
+ WDT_OUT(0xF3,0x08);
+ switch(whichgp)
+ {
+ case 12:
+ WDT_IN(0x2A,ret); /* sets ret */
+ WDT_OUT(0x2A,ret|0x80); /* sets GP12 on */
+ break;
+ case 13:
+ WDT_IN(0x2B,ret);
+ WDT_OUT(0x2B,ret|0x01);
+ break;
+ case 16:
+ WDT_IN(0x2C,ret);
+ WDT_OUT(0x2C,ret|0x10);
+ break;
+ }
+ /* set timer to 0 initially */
+ WDT_OUT(0xF2,0);
+ WDT_IN(0xF4, status); /* so we don't set bit 0 by accident */
+ WDT_OUT(0xF4,(status&0x01)|0x40); /* bit 6 for seconds! */
+ WDT_DISABLE;
+ printk(KERN_INFO "W83977EF: initialized, using port %x, GP%d. timeout=%d nowayout=%d\n",wdt_io,whichgp,timeout,nowayout);
+ return 0;
+unreg_misc:
+ misc_deregister(&wdt977_miscdev);
+out:
+ return ret;
+}
+
+static void __exit nwwatchdog_exit(void)
+{
+ remove_proc_entry("watchdog",NULL);
+ misc_deregister(&wdt977_miscdev);
+ release_region(wdt_io,2);
+ /* we might not have gotten it... is this safe? */
+}
+
+EXPORT_NO_SYMBOLS;
+
+module_init(nwwatchdog_init);
+module_exit(nwwatchdog_exit);
+
+MODULE_LICENSE("GPL");