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linux/drivers/watchdog/iTCO_wdt.c
Jean Delvare 487722cf2d watchdog: Get rid of MODULE_ALIAS_MISCDEV statements 
I just can't find any value in MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR)
and MODULE_ALIAS_MISCDEV(TEMP_MINOR) statements.

Either the device is enumerated and the driver already has a module
alias (e.g. PCI, USB etc.) that will get the right driver loaded
automatically.

Or the device is not enumerated and loading its driver will lead to
more or less intrusive hardware poking. Such hardware poking should be
limited to a bare minimum, so the user should really decide which
drivers should be tried and in what order. Trying them all in
arbitrary order can't do any good.

On top of that, loading that many drivers at once bloats the kernel
log. Also many drivers will stay loaded afterward, bloating the output
of "lsmod" and wasting memory. Some modules (cs5535_mfgpt which gets
loaded as a dependency) can't even be unloaded!

If defining char-major-10-130 is needed then it should happen in
user-space.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Mike Frysinger <vapier.adi@gmail.com>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Zwane Mwaikambo <zwane@arm.linux.org.uk>
Cc: Jim Cromie <jim.cromie@gmail.com>
2013-11-17 19:38:13 +01:00

584 lines
17 KiB
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/*
* intel TCO Watchdog Driver
*
* (c) Copyright 2006-2011 Wim Van Sebroeck <wim@iguana.be>.
*
* 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.
*
* Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
* provide warranty for any of this software. This material is
* provided "AS-IS" and at no charge.
*
* The TCO watchdog is implemented in the following I/O controller hubs:
* (See the intel documentation on http://developer.intel.com.)
* document number 290655-003, 290677-014: 82801AA (ICH), 82801AB (ICHO)
* document number 290687-002, 298242-027: 82801BA (ICH2)
* document number 290733-003, 290739-013: 82801CA (ICH3-S)
* document number 290716-001, 290718-007: 82801CAM (ICH3-M)
* document number 290744-001, 290745-025: 82801DB (ICH4)
* document number 252337-001, 252663-008: 82801DBM (ICH4-M)
* document number 273599-001, 273645-002: 82801E (C-ICH)
* document number 252516-001, 252517-028: 82801EB (ICH5), 82801ER (ICH5R)
* document number 300641-004, 300884-013: 6300ESB
* document number 301473-002, 301474-026: 82801F (ICH6)
* document number 313082-001, 313075-006: 631xESB, 632xESB
* document number 307013-003, 307014-024: 82801G (ICH7)
* document number 322896-001, 322897-001: NM10
* document number 313056-003, 313057-017: 82801H (ICH8)
* document number 316972-004, 316973-012: 82801I (ICH9)
* document number 319973-002, 319974-002: 82801J (ICH10)
* document number 322169-001, 322170-003: 5 Series, 3400 Series (PCH)
* document number 320066-003, 320257-008: EP80597 (IICH)
* document number 324645-001, 324646-001: Cougar Point (CPT)
* document number TBD : Patsburg (PBG)
* document number TBD : DH89xxCC
* document number TBD : Panther Point
* document number TBD : Lynx Point
* document number TBD : Lynx Point-LP
*/
/*
* Includes, defines, variables, module parameters, ...
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
/* Module and version information */
#define DRV_NAME "iTCO_wdt"
#define DRV_VERSION "1.10"
/* Includes */
#include <linux/module.h> /* For module specific items */
#include <linux/moduleparam.h> /* For new moduleparam's */
#include <linux/types.h> /* For standard types (like size_t) */
#include <linux/errno.h> /* For the -ENODEV/... values */
#include <linux/kernel.h> /* For printk/panic/... */
#include <linux/watchdog.h> /* For the watchdog specific items */
#include <linux/init.h> /* For __init/__exit/... */
#include <linux/fs.h> /* For file operations */
#include <linux/platform_device.h> /* For platform_driver framework */
#include <linux/pci.h> /* For pci functions */
#include <linux/ioport.h> /* For io-port access */
#include <linux/spinlock.h> /* For spin_lock/spin_unlock/... */
#include <linux/uaccess.h> /* For copy_to_user/put_user/... */
#include <linux/io.h> /* For inb/outb/... */
#include <linux/mfd/core.h>
#include <linux/mfd/lpc_ich.h>
#include "iTCO_vendor.h"
/* Address definitions for the TCO */
/* TCO base address */
#define TCOBASE (iTCO_wdt_private.tco_res->start)
/* SMI Control and Enable Register */
#define SMI_EN (iTCO_wdt_private.smi_res->start)
#define TCO_RLD (TCOBASE + 0x00) /* TCO Timer Reload and Curr. Value */
#define TCOv1_TMR (TCOBASE + 0x01) /* TCOv1 Timer Initial Value */
#define TCO_DAT_IN (TCOBASE + 0x02) /* TCO Data In Register */
#define TCO_DAT_OUT (TCOBASE + 0x03) /* TCO Data Out Register */
#define TCO1_STS (TCOBASE + 0x04) /* TCO1 Status Register */
#define TCO2_STS (TCOBASE + 0x06) /* TCO2 Status Register */
#define TCO1_CNT (TCOBASE + 0x08) /* TCO1 Control Register */
#define TCO2_CNT (TCOBASE + 0x0a) /* TCO2 Control Register */
#define TCOv2_TMR (TCOBASE + 0x12) /* TCOv2 Timer Initial Value */
/* internal variables */
static struct { /* this is private data for the iTCO_wdt device */
/* TCO version/generation */
unsigned int iTCO_version;
struct resource *tco_res;
struct resource *smi_res;
struct resource *gcs_res;
/* NO_REBOOT flag is Memory-Mapped GCS register bit 5 (TCO version 2)*/
unsigned long __iomem *gcs;
/* the lock for io operations */
spinlock_t io_lock;
struct platform_device *dev;
/* the PCI-device */
struct pci_dev *pdev;
} iTCO_wdt_private;
/* module parameters */
#define WATCHDOG_TIMEOUT 30 /* 30 sec default heartbeat */
static int heartbeat = WATCHDOG_TIMEOUT; /* in seconds */
module_param(heartbeat, int, 0);
MODULE_PARM_DESC(heartbeat, "Watchdog timeout in seconds. "
"5..76 (TCO v1) or 3..614 (TCO v2), default="
__MODULE_STRING(WATCHDOG_TIMEOUT) ")");
static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout,
"Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
static int turn_SMI_watchdog_clear_off = 1;
module_param(turn_SMI_watchdog_clear_off, int, 0);
MODULE_PARM_DESC(turn_SMI_watchdog_clear_off,
"Turn off SMI clearing watchdog (depends on TCO-version)(default=1)");
/*
* Some TCO specific functions
*/
static inline unsigned int seconds_to_ticks(int seconds)
{
/* the internal timer is stored as ticks which decrement
* every 0.6 seconds */
return (seconds * 10) / 6;
}
static void iTCO_wdt_set_NO_REBOOT_bit(void)
{
u32 val32;
/* Set the NO_REBOOT bit: this disables reboots */
if (iTCO_wdt_private.iTCO_version == 2) {
val32 = readl(iTCO_wdt_private.gcs);
val32 |= 0x00000020;
writel(val32, iTCO_wdt_private.gcs);
} else if (iTCO_wdt_private.iTCO_version == 1) {
pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
val32 |= 0x00000002;
pci_write_config_dword(iTCO_wdt_private.pdev, 0xd4, val32);
}
}
static int iTCO_wdt_unset_NO_REBOOT_bit(void)
{
int ret = 0;
u32 val32;
/* Unset the NO_REBOOT bit: this enables reboots */
if (iTCO_wdt_private.iTCO_version == 2) {
val32 = readl(iTCO_wdt_private.gcs);
val32 &= 0xffffffdf;
writel(val32, iTCO_wdt_private.gcs);
val32 = readl(iTCO_wdt_private.gcs);
if (val32 & 0x00000020)
ret = -EIO;
} else if (iTCO_wdt_private.iTCO_version == 1) {
pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
val32 &= 0xfffffffd;
pci_write_config_dword(iTCO_wdt_private.pdev, 0xd4, val32);
pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
if (val32 & 0x00000002)
ret = -EIO;
}
return ret; /* returns: 0 = OK, -EIO = Error */
}
static int iTCO_wdt_start(struct watchdog_device *wd_dev)
{
unsigned int val;
spin_lock(&iTCO_wdt_private.io_lock);
iTCO_vendor_pre_start(iTCO_wdt_private.smi_res, wd_dev->timeout);
/* disable chipset's NO_REBOOT bit */
if (iTCO_wdt_unset_NO_REBOOT_bit()) {
spin_unlock(&iTCO_wdt_private.io_lock);
pr_err("failed to reset NO_REBOOT flag, reboot disabled by hardware/BIOS\n");
return -EIO;
}
/* Force the timer to its reload value by writing to the TCO_RLD
register */
if (iTCO_wdt_private.iTCO_version == 2)
outw(0x01, TCO_RLD);
else if (iTCO_wdt_private.iTCO_version == 1)
outb(0x01, TCO_RLD);
/* Bit 11: TCO Timer Halt -> 0 = The TCO timer is enabled to count */
val = inw(TCO1_CNT);
val &= 0xf7ff;
outw(val, TCO1_CNT);
val = inw(TCO1_CNT);
spin_unlock(&iTCO_wdt_private.io_lock);
if (val & 0x0800)
return -1;
return 0;
}
static int iTCO_wdt_stop(struct watchdog_device *wd_dev)
{
unsigned int val;
spin_lock(&iTCO_wdt_private.io_lock);
iTCO_vendor_pre_stop(iTCO_wdt_private.smi_res);
/* Bit 11: TCO Timer Halt -> 1 = The TCO timer is disabled */
val = inw(TCO1_CNT);
val |= 0x0800;
outw(val, TCO1_CNT);
val = inw(TCO1_CNT);
/* Set the NO_REBOOT bit to prevent later reboots, just for sure */
iTCO_wdt_set_NO_REBOOT_bit();
spin_unlock(&iTCO_wdt_private.io_lock);
if ((val & 0x0800) == 0)
return -1;
return 0;
}
static int iTCO_wdt_ping(struct watchdog_device *wd_dev)
{
spin_lock(&iTCO_wdt_private.io_lock);
iTCO_vendor_pre_keepalive(iTCO_wdt_private.smi_res, wd_dev->timeout);
/* Reload the timer by writing to the TCO Timer Counter register */
if (iTCO_wdt_private.iTCO_version == 2)
outw(0x01, TCO_RLD);
else if (iTCO_wdt_private.iTCO_version == 1) {
/* Reset the timeout status bit so that the timer
* needs to count down twice again before rebooting */
outw(0x0008, TCO1_STS); /* write 1 to clear bit */
outb(0x01, TCO_RLD);
}
spin_unlock(&iTCO_wdt_private.io_lock);
return 0;
}
static int iTCO_wdt_set_timeout(struct watchdog_device *wd_dev, unsigned int t)
{
unsigned int val16;
unsigned char val8;
unsigned int tmrval;
tmrval = seconds_to_ticks(t);
/* For TCO v1 the timer counts down twice before rebooting */
if (iTCO_wdt_private.iTCO_version == 1)
tmrval /= 2;
/* from the specs: */
/* "Values of 0h-3h are ignored and should not be attempted" */
if (tmrval < 0x04)
return -EINVAL;
if (((iTCO_wdt_private.iTCO_version == 2) && (tmrval > 0x3ff)) ||
((iTCO_wdt_private.iTCO_version == 1) && (tmrval > 0x03f)))
return -EINVAL;
iTCO_vendor_pre_set_heartbeat(tmrval);
/* Write new heartbeat to watchdog */
if (iTCO_wdt_private.iTCO_version == 2) {
spin_lock(&iTCO_wdt_private.io_lock);
val16 = inw(TCOv2_TMR);
val16 &= 0xfc00;
val16 |= tmrval;
outw(val16, TCOv2_TMR);
val16 = inw(TCOv2_TMR);
spin_unlock(&iTCO_wdt_private.io_lock);
if ((val16 & 0x3ff) != tmrval)
return -EINVAL;
} else if (iTCO_wdt_private.iTCO_version == 1) {
spin_lock(&iTCO_wdt_private.io_lock);
val8 = inb(TCOv1_TMR);
val8 &= 0xc0;
val8 |= (tmrval & 0xff);
outb(val8, TCOv1_TMR);
val8 = inb(TCOv1_TMR);
spin_unlock(&iTCO_wdt_private.io_lock);
if ((val8 & 0x3f) != tmrval)
return -EINVAL;
}
wd_dev->timeout = t;
return 0;
}
static unsigned int iTCO_wdt_get_timeleft(struct watchdog_device *wd_dev)
{
unsigned int val16;
unsigned char val8;
unsigned int time_left = 0;
/* read the TCO Timer */
if (iTCO_wdt_private.iTCO_version == 2) {
spin_lock(&iTCO_wdt_private.io_lock);
val16 = inw(TCO_RLD);
val16 &= 0x3ff;
spin_unlock(&iTCO_wdt_private.io_lock);
time_left = (val16 * 6) / 10;
} else if (iTCO_wdt_private.iTCO_version == 1) {
spin_lock(&iTCO_wdt_private.io_lock);
val8 = inb(TCO_RLD);
val8 &= 0x3f;
if (!(inw(TCO1_STS) & 0x0008))
val8 += (inb(TCOv1_TMR) & 0x3f);
spin_unlock(&iTCO_wdt_private.io_lock);
time_left = (val8 * 6) / 10;
}
return time_left;
}
/*
* Kernel Interfaces
*/
static const struct watchdog_info ident = {
.options = WDIOF_SETTIMEOUT |
WDIOF_KEEPALIVEPING |
WDIOF_MAGICCLOSE,
.firmware_version = 0,
.identity = DRV_NAME,
};
static const struct watchdog_ops iTCO_wdt_ops = {
.owner = THIS_MODULE,
.start = iTCO_wdt_start,
.stop = iTCO_wdt_stop,
.ping = iTCO_wdt_ping,
.set_timeout = iTCO_wdt_set_timeout,
.get_timeleft = iTCO_wdt_get_timeleft,
};
static struct watchdog_device iTCO_wdt_watchdog_dev = {
.info = &ident,
.ops = &iTCO_wdt_ops,
};
/*
* Init & exit routines
*/
static void iTCO_wdt_cleanup(void)
{
/* Stop the timer before we leave */
if (!nowayout)
iTCO_wdt_stop(&iTCO_wdt_watchdog_dev);
/* Deregister */
watchdog_unregister_device(&iTCO_wdt_watchdog_dev);
/* release resources */
release_region(iTCO_wdt_private.tco_res->start,
resource_size(iTCO_wdt_private.tco_res));
release_region(iTCO_wdt_private.smi_res->start,
resource_size(iTCO_wdt_private.smi_res));
if (iTCO_wdt_private.iTCO_version == 2) {
iounmap(iTCO_wdt_private.gcs);
release_mem_region(iTCO_wdt_private.gcs_res->start,
resource_size(iTCO_wdt_private.gcs_res));
}
iTCO_wdt_private.tco_res = NULL;
iTCO_wdt_private.smi_res = NULL;
iTCO_wdt_private.gcs_res = NULL;
iTCO_wdt_private.gcs = NULL;
}
static int iTCO_wdt_probe(struct platform_device *dev)
{
int ret = -ENODEV;
unsigned long val32;
struct lpc_ich_info *ich_info = dev_get_platdata(&dev->dev);
if (!ich_info)
goto out;
spin_lock_init(&iTCO_wdt_private.io_lock);
iTCO_wdt_private.tco_res =
platform_get_resource(dev, IORESOURCE_IO, ICH_RES_IO_TCO);
if (!iTCO_wdt_private.tco_res)
goto out;
iTCO_wdt_private.smi_res =
platform_get_resource(dev, IORESOURCE_IO, ICH_RES_IO_SMI);
if (!iTCO_wdt_private.smi_res)
goto out;
iTCO_wdt_private.iTCO_version = ich_info->iTCO_version;
iTCO_wdt_private.dev = dev;
iTCO_wdt_private.pdev = to_pci_dev(dev->dev.parent);
/*
* Get the Memory-Mapped GCS register, we need it for the
* NO_REBOOT flag (TCO v2).
*/
if (iTCO_wdt_private.iTCO_version == 2) {
iTCO_wdt_private.gcs_res = platform_get_resource(dev,
IORESOURCE_MEM,
ICH_RES_MEM_GCS);
if (!iTCO_wdt_private.gcs_res)
goto out;
if (!request_mem_region(iTCO_wdt_private.gcs_res->start,
resource_size(iTCO_wdt_private.gcs_res), dev->name)) {
ret = -EBUSY;
goto out;
}
iTCO_wdt_private.gcs = ioremap(iTCO_wdt_private.gcs_res->start,
resource_size(iTCO_wdt_private.gcs_res));
if (!iTCO_wdt_private.gcs) {
ret = -EIO;
goto unreg_gcs;
}
}
/* Check chipset's NO_REBOOT bit */
if (iTCO_wdt_unset_NO_REBOOT_bit() && iTCO_vendor_check_noreboot_on()) {
pr_info("unable to reset NO_REBOOT flag, device disabled by hardware/BIOS\n");
ret = -ENODEV; /* Cannot reset NO_REBOOT bit */
goto unmap_gcs;
}
/* Set the NO_REBOOT bit to prevent later reboots, just for sure */
iTCO_wdt_set_NO_REBOOT_bit();
/* The TCO logic uses the TCO_EN bit in the SMI_EN register */
if (!request_region(iTCO_wdt_private.smi_res->start,
resource_size(iTCO_wdt_private.smi_res), dev->name)) {
pr_err("I/O address 0x%04llx already in use, device disabled\n",
(u64)SMI_EN);
ret = -EBUSY;
goto unmap_gcs;
}
if (turn_SMI_watchdog_clear_off >= iTCO_wdt_private.iTCO_version) {
/*
* Bit 13: TCO_EN -> 0
* Disables TCO logic generating an SMI#
*/
val32 = inl(SMI_EN);
val32 &= 0xffffdfff; /* Turn off SMI clearing watchdog */
outl(val32, SMI_EN);
}
if (!request_region(iTCO_wdt_private.tco_res->start,
resource_size(iTCO_wdt_private.tco_res), dev->name)) {
pr_err("I/O address 0x%04llx already in use, device disabled\n",
(u64)TCOBASE);
ret = -EBUSY;
goto unreg_smi;
}
pr_info("Found a %s TCO device (Version=%d, TCOBASE=0x%04llx)\n",
ich_info->name, ich_info->iTCO_version, (u64)TCOBASE);
/* Clear out the (probably old) status */
outw(0x0008, TCO1_STS); /* Clear the Time Out Status bit */
outw(0x0002, TCO2_STS); /* Clear SECOND_TO_STS bit */
outw(0x0004, TCO2_STS); /* Clear BOOT_STS bit */
iTCO_wdt_watchdog_dev.bootstatus = 0;
iTCO_wdt_watchdog_dev.timeout = WATCHDOG_TIMEOUT;
watchdog_set_nowayout(&iTCO_wdt_watchdog_dev, nowayout);
iTCO_wdt_watchdog_dev.parent = dev->dev.parent;
/* Make sure the watchdog is not running */
iTCO_wdt_stop(&iTCO_wdt_watchdog_dev);
/* Check that the heartbeat value is within it's range;
if not reset to the default */
if (iTCO_wdt_set_timeout(&iTCO_wdt_watchdog_dev, heartbeat)) {
iTCO_wdt_set_timeout(&iTCO_wdt_watchdog_dev, WATCHDOG_TIMEOUT);
pr_info("timeout value out of range, using %d\n",
WATCHDOG_TIMEOUT);
}
ret = watchdog_register_device(&iTCO_wdt_watchdog_dev);
if (ret != 0) {
pr_err("cannot register watchdog device (err=%d)\n", ret);
goto unreg_tco;
}
pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
heartbeat, nowayout);
return 0;
unreg_tco:
release_region(iTCO_wdt_private.tco_res->start,
resource_size(iTCO_wdt_private.tco_res));
unreg_smi:
release_region(iTCO_wdt_private.smi_res->start,
resource_size(iTCO_wdt_private.smi_res));
unmap_gcs:
if (iTCO_wdt_private.iTCO_version == 2)
iounmap(iTCO_wdt_private.gcs);
unreg_gcs:
if (iTCO_wdt_private.iTCO_version == 2)
release_mem_region(iTCO_wdt_private.gcs_res->start,
resource_size(iTCO_wdt_private.gcs_res));
out:
iTCO_wdt_private.tco_res = NULL;
iTCO_wdt_private.smi_res = NULL;
iTCO_wdt_private.gcs_res = NULL;
iTCO_wdt_private.gcs = NULL;
return ret;
}
static int iTCO_wdt_remove(struct platform_device *dev)
{
if (iTCO_wdt_private.tco_res || iTCO_wdt_private.smi_res)
iTCO_wdt_cleanup();
return 0;
}
static void iTCO_wdt_shutdown(struct platform_device *dev)
{
iTCO_wdt_stop(NULL);
}
static struct platform_driver iTCO_wdt_driver = {
.probe = iTCO_wdt_probe,
.remove = iTCO_wdt_remove,
.shutdown = iTCO_wdt_shutdown,
.driver = {
.owner = THIS_MODULE,
.name = DRV_NAME,
},
};
static int __init iTCO_wdt_init_module(void)
{
int err;
pr_info("Intel TCO WatchDog Timer Driver v%s\n", DRV_VERSION);
err = platform_driver_register(&iTCO_wdt_driver);
if (err)
return err;
return 0;
}
static void __exit iTCO_wdt_cleanup_module(void)
{
platform_driver_unregister(&iTCO_wdt_driver);
pr_info("Watchdog Module Unloaded\n");
}
module_init(iTCO_wdt_init_module);
module_exit(iTCO_wdt_cleanup_module);
MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
MODULE_DESCRIPTION("Intel TCO WatchDog Timer Driver");
MODULE_VERSION(DRV_VERSION);
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRV_NAME);
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