forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
354 lines
7.3 KiB
354 lines
7.3 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
|
/* |
|
* Watchdog Timer Driver |
|
* for ITE IT87xx Environment Control - Low Pin Count Input / Output |
|
* |
|
* (c) Copyright 2007 Oliver Schuster <[email protected]> |
|
* |
|
* Based on softdog.c by Alan Cox, |
|
* 83977f_wdt.c by Jose Goncalves, |
|
* it87.c by Chris Gauthron, Jean Delvare |
|
* |
|
* Data-sheets: Publicly available at the ITE website |
|
* http://www.ite.com.tw/ |
|
* |
|
* Support of the watchdog timers, which are available on |
|
* IT8607, IT8620, IT8622, IT8625, IT8628, IT8655, IT8665, IT8686, |
|
* IT8702, IT8712, IT8716, IT8718, IT8720, IT8721, IT8726, IT8728, |
|
* IT8772, IT8783 and IT8784. |
|
*/ |
|
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
|
|
|
#include <linux/init.h> |
|
#include <linux/io.h> |
|
#include <linux/kernel.h> |
|
#include <linux/module.h> |
|
#include <linux/moduleparam.h> |
|
#include <linux/types.h> |
|
#include <linux/watchdog.h> |
|
|
|
#define WATCHDOG_NAME "IT87 WDT" |
|
|
|
/* Defaults for Module Parameter */ |
|
#define DEFAULT_TIMEOUT 60 |
|
#define DEFAULT_TESTMODE 0 |
|
#define DEFAULT_NOWAYOUT WATCHDOG_NOWAYOUT |
|
|
|
/* IO Ports */ |
|
#define REG 0x2e |
|
#define VAL 0x2f |
|
|
|
/* Logical device Numbers LDN */ |
|
#define GPIO 0x07 |
|
|
|
/* Configuration Registers and Functions */ |
|
#define LDNREG 0x07 |
|
#define CHIPID 0x20 |
|
#define CHIPREV 0x22 |
|
|
|
/* Chip Id numbers */ |
|
#define NO_DEV_ID 0xffff |
|
#define IT8607_ID 0x8607 |
|
#define IT8620_ID 0x8620 |
|
#define IT8622_ID 0x8622 |
|
#define IT8625_ID 0x8625 |
|
#define IT8628_ID 0x8628 |
|
#define IT8655_ID 0x8655 |
|
#define IT8665_ID 0x8665 |
|
#define IT8686_ID 0x8686 |
|
#define IT8702_ID 0x8702 |
|
#define IT8705_ID 0x8705 |
|
#define IT8712_ID 0x8712 |
|
#define IT8716_ID 0x8716 |
|
#define IT8718_ID 0x8718 |
|
#define IT8720_ID 0x8720 |
|
#define IT8721_ID 0x8721 |
|
#define IT8726_ID 0x8726 /* the data sheet suggest wrongly 0x8716 */ |
|
#define IT8728_ID 0x8728 |
|
#define IT8772_ID 0x8772 |
|
#define IT8783_ID 0x8783 |
|
#define IT8784_ID 0x8784 |
|
#define IT8786_ID 0x8786 |
|
|
|
/* GPIO Configuration Registers LDN=0x07 */ |
|
#define WDTCTRL 0x71 |
|
#define WDTCFG 0x72 |
|
#define WDTVALLSB 0x73 |
|
#define WDTVALMSB 0x74 |
|
|
|
/* GPIO Bits WDTCFG */ |
|
#define WDT_TOV1 0x80 |
|
#define WDT_KRST 0x40 |
|
#define WDT_TOVE 0x20 |
|
#define WDT_PWROK 0x10 /* not in it8721 */ |
|
#define WDT_INT_MASK 0x0f |
|
|
|
static unsigned int max_units, chip_type; |
|
|
|
static unsigned int timeout = DEFAULT_TIMEOUT; |
|
static int testmode = DEFAULT_TESTMODE; |
|
static bool nowayout = DEFAULT_NOWAYOUT; |
|
|
|
module_param(timeout, int, 0); |
|
MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds, default=" |
|
__MODULE_STRING(DEFAULT_TIMEOUT)); |
|
module_param(testmode, int, 0); |
|
MODULE_PARM_DESC(testmode, "Watchdog test mode (1 = no reboot), default=" |
|
__MODULE_STRING(DEFAULT_TESTMODE)); |
|
module_param(nowayout, bool, 0); |
|
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started, default=" |
|
__MODULE_STRING(WATCHDOG_NOWAYOUT)); |
|
|
|
/* Superio Chip */ |
|
|
|
static inline int superio_enter(void) |
|
{ |
|
/* |
|
* Try to reserve REG and REG + 1 for exclusive access. |
|
*/ |
|
if (!request_muxed_region(REG, 2, WATCHDOG_NAME)) |
|
return -EBUSY; |
|
|
|
outb(0x87, REG); |
|
outb(0x01, REG); |
|
outb(0x55, REG); |
|
outb(0x55, REG); |
|
return 0; |
|
} |
|
|
|
static inline void superio_exit(void) |
|
{ |
|
outb(0x02, REG); |
|
outb(0x02, VAL); |
|
release_region(REG, 2); |
|
} |
|
|
|
static inline void superio_select(int ldn) |
|
{ |
|
outb(LDNREG, REG); |
|
outb(ldn, VAL); |
|
} |
|
|
|
static inline int superio_inb(int reg) |
|
{ |
|
outb(reg, REG); |
|
return inb(VAL); |
|
} |
|
|
|
static inline void superio_outb(int val, int reg) |
|
{ |
|
outb(reg, REG); |
|
outb(val, VAL); |
|
} |
|
|
|
static inline int superio_inw(int reg) |
|
{ |
|
int val; |
|
outb(reg++, REG); |
|
val = inb(VAL) << 8; |
|
outb(reg, REG); |
|
val |= inb(VAL); |
|
return val; |
|
} |
|
|
|
/* Internal function, should be called after superio_select(GPIO) */ |
|
static void _wdt_update_timeout(unsigned int t) |
|
{ |
|
unsigned char cfg = WDT_KRST; |
|
|
|
if (testmode) |
|
cfg = 0; |
|
|
|
if (t <= max_units) |
|
cfg |= WDT_TOV1; |
|
else |
|
t /= 60; |
|
|
|
if (chip_type != IT8721_ID) |
|
cfg |= WDT_PWROK; |
|
|
|
superio_outb(cfg, WDTCFG); |
|
superio_outb(t, WDTVALLSB); |
|
if (max_units > 255) |
|
superio_outb(t >> 8, WDTVALMSB); |
|
} |
|
|
|
static int wdt_update_timeout(unsigned int t) |
|
{ |
|
int ret; |
|
|
|
ret = superio_enter(); |
|
if (ret) |
|
return ret; |
|
|
|
superio_select(GPIO); |
|
_wdt_update_timeout(t); |
|
superio_exit(); |
|
|
|
return 0; |
|
} |
|
|
|
static int wdt_round_time(int t) |
|
{ |
|
t += 59; |
|
t -= t % 60; |
|
return t; |
|
} |
|
|
|
/* watchdog timer handling */ |
|
|
|
static int wdt_start(struct watchdog_device *wdd) |
|
{ |
|
return wdt_update_timeout(wdd->timeout); |
|
} |
|
|
|
static int wdt_stop(struct watchdog_device *wdd) |
|
{ |
|
return wdt_update_timeout(0); |
|
} |
|
|
|
/** |
|
* wdt_set_timeout - set a new timeout value with watchdog ioctl |
|
* @t: timeout value in seconds |
|
* |
|
* The hardware device has a 8 or 16 bit watchdog timer (depends on |
|
* chip version) that can be configured to count seconds or minutes. |
|
* |
|
* Used within WDIOC_SETTIMEOUT watchdog device ioctl. |
|
*/ |
|
|
|
static int wdt_set_timeout(struct watchdog_device *wdd, unsigned int t) |
|
{ |
|
int ret = 0; |
|
|
|
if (t > max_units) |
|
t = wdt_round_time(t); |
|
|
|
wdd->timeout = t; |
|
|
|
if (watchdog_hw_running(wdd)) |
|
ret = wdt_update_timeout(t); |
|
|
|
return ret; |
|
} |
|
|
|
static const struct watchdog_info ident = { |
|
.options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, |
|
.firmware_version = 1, |
|
.identity = WATCHDOG_NAME, |
|
}; |
|
|
|
static const struct watchdog_ops wdt_ops = { |
|
.owner = THIS_MODULE, |
|
.start = wdt_start, |
|
.stop = wdt_stop, |
|
.set_timeout = wdt_set_timeout, |
|
}; |
|
|
|
static struct watchdog_device wdt_dev = { |
|
.info = &ident, |
|
.ops = &wdt_ops, |
|
.min_timeout = 1, |
|
}; |
|
|
|
static int __init it87_wdt_init(void) |
|
{ |
|
u8 chip_rev; |
|
int rc; |
|
|
|
rc = superio_enter(); |
|
if (rc) |
|
return rc; |
|
|
|
chip_type = superio_inw(CHIPID); |
|
chip_rev = superio_inb(CHIPREV) & 0x0f; |
|
superio_exit(); |
|
|
|
switch (chip_type) { |
|
case IT8702_ID: |
|
max_units = 255; |
|
break; |
|
case IT8712_ID: |
|
max_units = (chip_rev < 8) ? 255 : 65535; |
|
break; |
|
case IT8716_ID: |
|
case IT8726_ID: |
|
max_units = 65535; |
|
break; |
|
case IT8607_ID: |
|
case IT8620_ID: |
|
case IT8622_ID: |
|
case IT8625_ID: |
|
case IT8628_ID: |
|
case IT8655_ID: |
|
case IT8665_ID: |
|
case IT8686_ID: |
|
case IT8718_ID: |
|
case IT8720_ID: |
|
case IT8721_ID: |
|
case IT8728_ID: |
|
case IT8772_ID: |
|
case IT8783_ID: |
|
case IT8784_ID: |
|
case IT8786_ID: |
|
max_units = 65535; |
|
break; |
|
case IT8705_ID: |
|
pr_err("Unsupported Chip found, Chip %04x Revision %02x\n", |
|
chip_type, chip_rev); |
|
return -ENODEV; |
|
case NO_DEV_ID: |
|
pr_err("no device\n"); |
|
return -ENODEV; |
|
default: |
|
pr_err("Unknown Chip found, Chip %04x Revision %04x\n", |
|
chip_type, chip_rev); |
|
return -ENODEV; |
|
} |
|
|
|
rc = superio_enter(); |
|
if (rc) |
|
return rc; |
|
|
|
superio_select(GPIO); |
|
superio_outb(WDT_TOV1, WDTCFG); |
|
superio_outb(0x00, WDTCTRL); |
|
superio_exit(); |
|
|
|
if (timeout < 1 || timeout > max_units * 60) { |
|
timeout = DEFAULT_TIMEOUT; |
|
pr_warn("Timeout value out of range, use default %d sec\n", |
|
DEFAULT_TIMEOUT); |
|
} |
|
|
|
if (timeout > max_units) |
|
timeout = wdt_round_time(timeout); |
|
|
|
wdt_dev.timeout = timeout; |
|
wdt_dev.max_timeout = max_units * 60; |
|
|
|
watchdog_stop_on_reboot(&wdt_dev); |
|
rc = watchdog_register_device(&wdt_dev); |
|
if (rc) { |
|
pr_err("Cannot register watchdog device (err=%d)\n", rc); |
|
return rc; |
|
} |
|
|
|
pr_info("Chip IT%04x revision %d initialized. timeout=%d sec (nowayout=%d testmode=%d)\n", |
|
chip_type, chip_rev, timeout, nowayout, testmode); |
|
|
|
return 0; |
|
} |
|
|
|
static void __exit it87_wdt_exit(void) |
|
{ |
|
watchdog_unregister_device(&wdt_dev); |
|
} |
|
|
|
module_init(it87_wdt_init); |
|
module_exit(it87_wdt_exit); |
|
|
|
MODULE_AUTHOR("Oliver Schuster"); |
|
MODULE_DESCRIPTION("Hardware Watchdog Device Driver for IT87xx EC-LPC I/O"); |
|
MODULE_LICENSE("GPL");
|
|
|