linux/drivers/watchdog/ibmasr.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

422 lines
9.4 KiB
C

/*
* IBM Automatic Server Restart driver.
*
* Copyright (c) 2005 Andrey Panin <pazke@donpac.ru>
*
* Based on driver written by Pete Reynolds.
* Copyright (c) IBM Corporation, 1998-2004.
*
* This software may be used and distributed according to the terms
* of the GNU Public License, incorporated herein by reference.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/timer.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/dmi.h>
#include <linux/io.h>
#include <linux/uaccess.h>
enum {
ASMTYPE_UNKNOWN,
ASMTYPE_TOPAZ,
ASMTYPE_JASPER,
ASMTYPE_PEARL,
ASMTYPE_JUNIPER,
ASMTYPE_SPRUCE,
};
#define TOPAZ_ASR_REG_OFFSET 4
#define TOPAZ_ASR_TOGGLE 0x40
#define TOPAZ_ASR_DISABLE 0x80
/* PEARL ASR S/W REGISTER SUPERIO PORT ADDRESSES */
#define PEARL_BASE 0xe04
#define PEARL_WRITE 0xe06
#define PEARL_READ 0xe07
#define PEARL_ASR_DISABLE_MASK 0x80 /* bit 7: disable = 1, enable = 0 */
#define PEARL_ASR_TOGGLE_MASK 0x40 /* bit 6: 0, then 1, then 0 */
/* JASPER OFFSET FROM SIO BASE ADDR TO ASR S/W REGISTERS. */
#define JASPER_ASR_REG_OFFSET 0x38
#define JASPER_ASR_DISABLE_MASK 0x01 /* bit 0: disable = 1, enable = 0 */
#define JASPER_ASR_TOGGLE_MASK 0x02 /* bit 1: 0, then 1, then 0 */
#define JUNIPER_BASE_ADDRESS 0x54b /* Base address of Juniper ASR */
#define JUNIPER_ASR_DISABLE_MASK 0x01 /* bit 0: disable = 1 enable = 0 */
#define JUNIPER_ASR_TOGGLE_MASK 0x02 /* bit 1: 0, then 1, then 0 */
#define SPRUCE_BASE_ADDRESS 0x118e /* Base address of Spruce ASR */
#define SPRUCE_ASR_DISABLE_MASK 0x01 /* bit 1: disable = 1 enable = 0 */
#define SPRUCE_ASR_TOGGLE_MASK 0x02 /* bit 0: 0, then 1, then 0 */
static bool nowayout = WATCHDOG_NOWAYOUT;
static unsigned long asr_is_open;
static char asr_expect_close;
static unsigned int asr_type, asr_base, asr_length;
static unsigned int asr_read_addr, asr_write_addr;
static unsigned char asr_toggle_mask, asr_disable_mask;
static DEFINE_SPINLOCK(asr_lock);
static void __asr_toggle(void)
{
unsigned char reg;
reg = inb(asr_read_addr);
outb(reg & ~asr_toggle_mask, asr_write_addr);
reg = inb(asr_read_addr);
outb(reg | asr_toggle_mask, asr_write_addr);
reg = inb(asr_read_addr);
outb(reg & ~asr_toggle_mask, asr_write_addr);
reg = inb(asr_read_addr);
}
static void asr_toggle(void)
{
spin_lock(&asr_lock);
__asr_toggle();
spin_unlock(&asr_lock);
}
static void asr_enable(void)
{
unsigned char reg;
spin_lock(&asr_lock);
if (asr_type == ASMTYPE_TOPAZ) {
/* asr_write_addr == asr_read_addr */
reg = inb(asr_read_addr);
outb(reg & ~(TOPAZ_ASR_TOGGLE | TOPAZ_ASR_DISABLE),
asr_read_addr);
} else {
/*
* First make sure the hardware timer is reset by toggling
* ASR hardware timer line.
*/
__asr_toggle();
reg = inb(asr_read_addr);
outb(reg & ~asr_disable_mask, asr_write_addr);
}
reg = inb(asr_read_addr);
spin_unlock(&asr_lock);
}
static void asr_disable(void)
{
unsigned char reg;
spin_lock(&asr_lock);
reg = inb(asr_read_addr);
if (asr_type == ASMTYPE_TOPAZ)
/* asr_write_addr == asr_read_addr */
outb(reg | TOPAZ_ASR_TOGGLE | TOPAZ_ASR_DISABLE,
asr_read_addr);
else {
outb(reg | asr_toggle_mask, asr_write_addr);
reg = inb(asr_read_addr);
outb(reg | asr_disable_mask, asr_write_addr);
}
reg = inb(asr_read_addr);
spin_unlock(&asr_lock);
}
static int __init asr_get_base_address(void)
{
unsigned char low, high;
const char *type = "";
asr_length = 1;
switch (asr_type) {
case ASMTYPE_TOPAZ:
/* SELECT SuperIO CHIP FOR QUERYING
(WRITE 0x07 TO BOTH 0x2E and 0x2F) */
outb(0x07, 0x2e);
outb(0x07, 0x2f);
/* SELECT AND READ THE HIGH-NIBBLE OF THE GPIO BASE ADDRESS */
outb(0x60, 0x2e);
high = inb(0x2f);
/* SELECT AND READ THE LOW-NIBBLE OF THE GPIO BASE ADDRESS */
outb(0x61, 0x2e);
low = inb(0x2f);
asr_base = (high << 16) | low;
asr_read_addr = asr_write_addr =
asr_base + TOPAZ_ASR_REG_OFFSET;
asr_length = 5;
break;
case ASMTYPE_JASPER:
type = "Jaspers ";
#if 0
u32 r;
/* Suggested fix */
pdev = pci_get_bus_and_slot(0, DEVFN(0x1f, 0));
if (pdev == NULL)
return -ENODEV;
pci_read_config_dword(pdev, 0x58, &r);
asr_base = r & 0xFFFE;
pci_dev_put(pdev);
#else
/* FIXME: need to use pci_config_lock here,
but it's not exported */
/* spin_lock_irqsave(&pci_config_lock, flags);*/
/* Select the SuperIO chip in the PCI I/O port register */
outl(0x8000f858, 0xcf8);
/* BUS 0, Slot 1F, fnc 0, offset 58 */
/*
* Read the base address for the SuperIO chip.
* Only the lower 16 bits are valid, but the address is word
* aligned so the last bit must be masked off.
*/
asr_base = inl(0xcfc) & 0xfffe;
/* spin_unlock_irqrestore(&pci_config_lock, flags);*/
#endif
asr_read_addr = asr_write_addr =
asr_base + JASPER_ASR_REG_OFFSET;
asr_toggle_mask = JASPER_ASR_TOGGLE_MASK;
asr_disable_mask = JASPER_ASR_DISABLE_MASK;
asr_length = JASPER_ASR_REG_OFFSET + 1;
break;
case ASMTYPE_PEARL:
type = "Pearls ";
asr_base = PEARL_BASE;
asr_read_addr = PEARL_READ;
asr_write_addr = PEARL_WRITE;
asr_toggle_mask = PEARL_ASR_TOGGLE_MASK;
asr_disable_mask = PEARL_ASR_DISABLE_MASK;
asr_length = 4;
break;
case ASMTYPE_JUNIPER:
type = "Junipers ";
asr_base = JUNIPER_BASE_ADDRESS;
asr_read_addr = asr_write_addr = asr_base;
asr_toggle_mask = JUNIPER_ASR_TOGGLE_MASK;
asr_disable_mask = JUNIPER_ASR_DISABLE_MASK;
break;
case ASMTYPE_SPRUCE:
type = "Spruce's ";
asr_base = SPRUCE_BASE_ADDRESS;
asr_read_addr = asr_write_addr = asr_base;
asr_toggle_mask = SPRUCE_ASR_TOGGLE_MASK;
asr_disable_mask = SPRUCE_ASR_DISABLE_MASK;
break;
}
if (!request_region(asr_base, asr_length, "ibmasr")) {
pr_err("address %#x already in use\n", asr_base);
return -EBUSY;
}
pr_info("found %sASR @ addr %#x\n", type, asr_base);
return 0;
}
static ssize_t asr_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
if (count) {
if (!nowayout) {
size_t i;
/* In case it was set long ago */
asr_expect_close = 0;
for (i = 0; i != count; i++) {
char c;
if (get_user(c, buf + i))
return -EFAULT;
if (c == 'V')
asr_expect_close = 42;
}
}
asr_toggle();
}
return count;
}
static long asr_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
static const struct watchdog_info ident = {
.options = WDIOF_KEEPALIVEPING |
WDIOF_MAGICCLOSE,
.identity = "IBM ASR",
};
void __user *argp = (void __user *)arg;
int __user *p = argp;
int heartbeat;
switch (cmd) {
case WDIOC_GETSUPPORT:
return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
return put_user(0, p);
case WDIOC_SETOPTIONS:
{
int new_options, retval = -EINVAL;
if (get_user(new_options, p))
return -EFAULT;
if (new_options & WDIOS_DISABLECARD) {
asr_disable();
retval = 0;
}
if (new_options & WDIOS_ENABLECARD) {
asr_enable();
asr_toggle();
retval = 0;
}
return retval;
}
case WDIOC_KEEPALIVE:
asr_toggle();
return 0;
/*
* The hardware has a fixed timeout value, so no WDIOC_SETTIMEOUT
* and WDIOC_GETTIMEOUT always returns 256.
*/
case WDIOC_GETTIMEOUT:
heartbeat = 256;
return put_user(heartbeat, p);
default:
return -ENOTTY;
}
}
static int asr_open(struct inode *inode, struct file *file)
{
if (test_and_set_bit(0, &asr_is_open))
return -EBUSY;
asr_toggle();
asr_enable();
return nonseekable_open(inode, file);
}
static int asr_release(struct inode *inode, struct file *file)
{
if (asr_expect_close == 42)
asr_disable();
else {
pr_crit("unexpected close, not stopping watchdog!\n");
asr_toggle();
}
clear_bit(0, &asr_is_open);
asr_expect_close = 0;
return 0;
}
static const struct file_operations asr_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = asr_write,
.unlocked_ioctl = asr_ioctl,
.open = asr_open,
.release = asr_release,
};
static struct miscdevice asr_miscdev = {
.minor = WATCHDOG_MINOR,
.name = "watchdog",
.fops = &asr_fops,
};
struct ibmasr_id {
const char *desc;
int type;
};
static struct ibmasr_id __initdata ibmasr_id_table[] = {
{ "IBM Automatic Server Restart - eserver xSeries 220", ASMTYPE_TOPAZ },
{ "IBM Automatic Server Restart - Machine Type 8673", ASMTYPE_PEARL },
{ "IBM Automatic Server Restart - Machine Type 8480", ASMTYPE_JASPER },
{ "IBM Automatic Server Restart - Machine Type 8482", ASMTYPE_JUNIPER },
{ "IBM Automatic Server Restart - Machine Type 8648", ASMTYPE_SPRUCE },
{ NULL }
};
static int __init ibmasr_init(void)
{
struct ibmasr_id *id;
int rc;
for (id = ibmasr_id_table; id->desc; id++) {
if (dmi_find_device(DMI_DEV_TYPE_OTHER, id->desc, NULL)) {
asr_type = id->type;
break;
}
}
if (!asr_type)
return -ENODEV;
rc = asr_get_base_address();
if (rc)
return rc;
rc = misc_register(&asr_miscdev);
if (rc < 0) {
release_region(asr_base, asr_length);
pr_err("failed to register misc device\n");
return rc;
}
return 0;
}
static void __exit ibmasr_exit(void)
{
if (!nowayout)
asr_disable();
misc_deregister(&asr_miscdev);
release_region(asr_base, asr_length);
}
module_init(ibmasr_init);
module_exit(ibmasr_exit);
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout,
"Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
MODULE_DESCRIPTION("IBM Automatic Server Restart driver");
MODULE_AUTHOR("Andrey Panin");
MODULE_LICENSE("GPL");