diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/watchdog/sch311x_wdt.c | 545 |
1 files changed, 545 insertions, 0 deletions
diff --git a/drivers/watchdog/sch311x_wdt.c b/drivers/watchdog/sch311x_wdt.c new file mode 100644 index 000000000..814cdf539 --- /dev/null +++ b/drivers/watchdog/sch311x_wdt.c @@ -0,0 +1,545 @@ +/* + * sch311x_wdt.c - Driver for the SCH311x Super-I/O chips + * integrated watchdog. + * + * (c) Copyright 2008 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. + */ + +/* + * Includes, defines, variables, module parameters, ... + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +/* 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/... */ +#include <linux/miscdevice.h> /* For struct miscdevice */ +#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/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/... */ + +/* Module and version information */ +#define DRV_NAME "sch311x_wdt" + +/* Runtime registers */ +#define GP60 0x47 +#define WDT_TIME_OUT 0x65 +#define WDT_VAL 0x66 +#define WDT_CFG 0x67 +#define WDT_CTRL 0x68 + +/* internal variables */ +static unsigned long sch311x_wdt_is_open; +static char sch311x_wdt_expect_close; +static struct platform_device *sch311x_wdt_pdev; + +static int sch311x_ioports[] = { 0x2e, 0x4e, 0x162e, 0x164e, 0x00 }; + +static struct { /* The devices private data */ + /* the Runtime Register base address */ + unsigned short runtime_reg; + /* The card's boot status */ + int boot_status; + /* the lock for io operations */ + spinlock_t io_lock; +} sch311x_wdt_data; + +/* Module load parameters */ +static unsigned short force_id; +module_param(force_id, ushort, 0); +MODULE_PARM_DESC(force_id, "Override the detected device ID"); + +#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */ +static int timeout = WATCHDOG_TIMEOUT; /* in seconds */ +module_param(timeout, int, 0); +MODULE_PARM_DESC(timeout, + "Watchdog timeout in seconds. 1<= timeout <=15300, 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) ")"); + +/* + * Super-IO functions + */ + +static inline void sch311x_sio_enter(int sio_config_port) +{ + outb(0x55, sio_config_port); +} + +static inline void sch311x_sio_exit(int sio_config_port) +{ + outb(0xaa, sio_config_port); +} + +static inline int sch311x_sio_inb(int sio_config_port, int reg) +{ + outb(reg, sio_config_port); + return inb(sio_config_port + 1); +} + +static inline void sch311x_sio_outb(int sio_config_port, int reg, int val) +{ + outb(reg, sio_config_port); + outb(val, sio_config_port + 1); +} + +/* + * Watchdog Operations + */ + +static void sch311x_wdt_set_timeout(int t) +{ + unsigned char timeout_unit = 0x80; + + /* When new timeout is bigger then 255 seconds, we will use minutes */ + if (t > 255) { + timeout_unit = 0; + t /= 60; + } + + /* -- Watchdog Timeout -- + * Bit 0-6 (Reserved) + * Bit 7 WDT Time-out Value Units Select + * (0 = Minutes, 1 = Seconds) + */ + outb(timeout_unit, sch311x_wdt_data.runtime_reg + WDT_TIME_OUT); + + /* -- Watchdog Timer Time-out Value -- + * Bit 0-7 Binary coded units (0=Disabled, 1..255) + */ + outb(t, sch311x_wdt_data.runtime_reg + WDT_VAL); +} + +static void sch311x_wdt_start(void) +{ + unsigned char t; + + spin_lock(&sch311x_wdt_data.io_lock); + + /* set watchdog's timeout */ + sch311x_wdt_set_timeout(timeout); + /* enable the watchdog */ + /* -- General Purpose I/O Bit 6.0 -- + * Bit 0, In/Out: 0 = Output, 1 = Input + * Bit 1, Polarity: 0 = No Invert, 1 = Invert + * Bit 2-3, Function select: 00 = GPI/O, 01 = LED1, 11 = WDT, + * 10 = Either Edge Triggered Intr.4 + * Bit 4-6 (Reserved) + * Bit 7, Output Type: 0 = Push Pull Bit, 1 = Open Drain + */ + t = inb(sch311x_wdt_data.runtime_reg + GP60); + outb((t & ~0x0d) | 0x0c, sch311x_wdt_data.runtime_reg + GP60); + + spin_unlock(&sch311x_wdt_data.io_lock); + +} + +static void sch311x_wdt_stop(void) +{ + unsigned char t; + + spin_lock(&sch311x_wdt_data.io_lock); + + /* stop the watchdog */ + t = inb(sch311x_wdt_data.runtime_reg + GP60); + outb((t & ~0x0d) | 0x01, sch311x_wdt_data.runtime_reg + GP60); + /* disable timeout by setting it to 0 */ + sch311x_wdt_set_timeout(0); + + spin_unlock(&sch311x_wdt_data.io_lock); +} + +static void sch311x_wdt_keepalive(void) +{ + spin_lock(&sch311x_wdt_data.io_lock); + sch311x_wdt_set_timeout(timeout); + spin_unlock(&sch311x_wdt_data.io_lock); +} + +static int sch311x_wdt_set_heartbeat(int t) +{ + if (t < 1 || t > (255*60)) + return -EINVAL; + + /* When new timeout is bigger then 255 seconds, + * we will round up to minutes (with a max of 255) */ + if (t > 255) + t = (((t - 1) / 60) + 1) * 60; + + timeout = t; + return 0; +} + +static void sch311x_wdt_get_status(int *status) +{ + unsigned char new_status; + + *status = 0; + + spin_lock(&sch311x_wdt_data.io_lock); + + /* -- Watchdog timer control -- + * Bit 0 Status Bit: 0 = Timer counting, 1 = Timeout occurred + * Bit 1 Reserved + * Bit 2 Force Timeout: 1 = Forces WD timeout event (self-cleaning) + * Bit 3 P20 Force Timeout enabled: + * 0 = P20 activity does not generate the WD timeout event + * 1 = P20 Allows rising edge of P20, from the keyboard + * controller, to force the WD timeout event. + * Bit 4-7 Reserved + */ + new_status = inb(sch311x_wdt_data.runtime_reg + WDT_CTRL); + if (new_status & 0x01) + *status |= WDIOF_CARDRESET; + + spin_unlock(&sch311x_wdt_data.io_lock); +} + +/* + * /dev/watchdog handling + */ + +static ssize_t sch311x_wdt_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + if (count) { + if (!nowayout) { + size_t i; + + sch311x_wdt_expect_close = 0; + + for (i = 0; i != count; i++) { + char c; + if (get_user(c, buf + i)) + return -EFAULT; + if (c == 'V') + sch311x_wdt_expect_close = 42; + } + } + sch311x_wdt_keepalive(); + } + return count; +} + +static long sch311x_wdt_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + int status; + int new_timeout; + void __user *argp = (void __user *)arg; + int __user *p = argp; + static const struct watchdog_info ident = { + .options = WDIOF_KEEPALIVEPING | + WDIOF_SETTIMEOUT | + WDIOF_MAGICCLOSE, + .firmware_version = 1, + .identity = DRV_NAME, + }; + + switch (cmd) { + case WDIOC_GETSUPPORT: + if (copy_to_user(argp, &ident, sizeof(ident))) + return -EFAULT; + break; + + case WDIOC_GETSTATUS: + { + sch311x_wdt_get_status(&status); + return put_user(status, p); + } + case WDIOC_GETBOOTSTATUS: + return put_user(sch311x_wdt_data.boot_status, p); + + case WDIOC_SETOPTIONS: + { + int options, retval = -EINVAL; + + if (get_user(options, p)) + return -EFAULT; + if (options & WDIOS_DISABLECARD) { + sch311x_wdt_stop(); + retval = 0; + } + if (options & WDIOS_ENABLECARD) { + sch311x_wdt_start(); + retval = 0; + } + return retval; + } + case WDIOC_KEEPALIVE: + sch311x_wdt_keepalive(); + break; + + case WDIOC_SETTIMEOUT: + if (get_user(new_timeout, p)) + return -EFAULT; + if (sch311x_wdt_set_heartbeat(new_timeout)) + return -EINVAL; + sch311x_wdt_keepalive(); + /* Fall through */ + case WDIOC_GETTIMEOUT: + return put_user(timeout, p); + default: + return -ENOTTY; + } + return 0; +} + +static int sch311x_wdt_open(struct inode *inode, struct file *file) +{ + if (test_and_set_bit(0, &sch311x_wdt_is_open)) + return -EBUSY; + /* + * Activate + */ + sch311x_wdt_start(); + return nonseekable_open(inode, file); +} + +static int sch311x_wdt_close(struct inode *inode, struct file *file) +{ + if (sch311x_wdt_expect_close == 42) { + sch311x_wdt_stop(); + } else { + pr_crit("Unexpected close, not stopping watchdog!\n"); + sch311x_wdt_keepalive(); + } + clear_bit(0, &sch311x_wdt_is_open); + sch311x_wdt_expect_close = 0; + return 0; +} + +/* + * Kernel Interfaces + */ + +static const struct file_operations sch311x_wdt_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .write = sch311x_wdt_write, + .unlocked_ioctl = sch311x_wdt_ioctl, + .open = sch311x_wdt_open, + .release = sch311x_wdt_close, +}; + +static struct miscdevice sch311x_wdt_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &sch311x_wdt_fops, +}; + +/* + * Init & exit routines + */ + +static int sch311x_wdt_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + int err; + + spin_lock_init(&sch311x_wdt_data.io_lock); + + if (!request_region(sch311x_wdt_data.runtime_reg + GP60, 1, DRV_NAME)) { + dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n", + sch311x_wdt_data.runtime_reg + GP60, + sch311x_wdt_data.runtime_reg + GP60); + err = -EBUSY; + goto exit; + } + + if (!request_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4, + DRV_NAME)) { + dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n", + sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, + sch311x_wdt_data.runtime_reg + WDT_CTRL); + err = -EBUSY; + goto exit_release_region; + } + + /* Make sure that the watchdog is not running */ + sch311x_wdt_stop(); + + /* Disable keyboard and mouse interaction and interrupt */ + /* -- Watchdog timer configuration -- + * Bit 0 Reserved + * Bit 1 Keyboard enable: 0* = No Reset, 1 = Reset WDT upon KBD Intr. + * Bit 2 Mouse enable: 0* = No Reset, 1 = Reset WDT upon Mouse Intr + * Bit 3 Reserved + * Bit 4-7 WDT Interrupt Mapping: (0000* = Disabled, + * 0001=IRQ1, 0010=(Invalid), 0011=IRQ3 to 1111=IRQ15) + */ + outb(0, sch311x_wdt_data.runtime_reg + WDT_CFG); + + /* Check that the heartbeat value is within it's range ; + * if not reset to the default */ + if (sch311x_wdt_set_heartbeat(timeout)) { + sch311x_wdt_set_heartbeat(WATCHDOG_TIMEOUT); + dev_info(dev, "timeout value must be 1<=x<=15300, using %d\n", + timeout); + } + + /* Get status at boot */ + sch311x_wdt_get_status(&sch311x_wdt_data.boot_status); + + sch311x_wdt_miscdev.parent = dev; + + err = misc_register(&sch311x_wdt_miscdev); + if (err != 0) { + dev_err(dev, "cannot register miscdev on minor=%d (err=%d)\n", + WATCHDOG_MINOR, err); + goto exit_release_region2; + } + + dev_info(dev, + "SMSC SCH311x WDT initialized. timeout=%d sec (nowayout=%d)\n", + timeout, nowayout); + + return 0; + +exit_release_region2: + release_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4); +exit_release_region: + release_region(sch311x_wdt_data.runtime_reg + GP60, 1); + sch311x_wdt_data.runtime_reg = 0; +exit: + return err; +} + +static int sch311x_wdt_remove(struct platform_device *pdev) +{ + /* Stop the timer before we leave */ + if (!nowayout) + sch311x_wdt_stop(); + + /* Deregister */ + misc_deregister(&sch311x_wdt_miscdev); + release_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4); + release_region(sch311x_wdt_data.runtime_reg + GP60, 1); + sch311x_wdt_data.runtime_reg = 0; + return 0; +} + +static void sch311x_wdt_shutdown(struct platform_device *dev) +{ + /* Turn the WDT off if we have a soft shutdown */ + sch311x_wdt_stop(); +} + +static struct platform_driver sch311x_wdt_driver = { + .probe = sch311x_wdt_probe, + .remove = sch311x_wdt_remove, + .shutdown = sch311x_wdt_shutdown, + .driver = { + .name = DRV_NAME, + }, +}; + +static int __init sch311x_detect(int sio_config_port, unsigned short *addr) +{ + int err = 0, reg; + unsigned short base_addr; + unsigned char dev_id; + + sch311x_sio_enter(sio_config_port); + + /* Check device ID. We currently know about: + * SCH3112 (0x7c), SCH3114 (0x7d), and SCH3116 (0x7f). */ + reg = force_id ? force_id : sch311x_sio_inb(sio_config_port, 0x20); + if (!(reg == 0x7c || reg == 0x7d || reg == 0x7f)) { + err = -ENODEV; + goto exit; + } + dev_id = reg == 0x7c ? 2 : reg == 0x7d ? 4 : 6; + + /* Select logical device A (runtime registers) */ + sch311x_sio_outb(sio_config_port, 0x07, 0x0a); + + /* Check if Logical Device Register is currently active */ + if ((sch311x_sio_inb(sio_config_port, 0x30) & 0x01) == 0) + pr_info("Seems that LDN 0x0a is not active...\n"); + + /* Get the base address of the runtime registers */ + base_addr = (sch311x_sio_inb(sio_config_port, 0x60) << 8) | + sch311x_sio_inb(sio_config_port, 0x61); + if (!base_addr) { + pr_err("Base address not set\n"); + err = -ENODEV; + goto exit; + } + *addr = base_addr; + + pr_info("Found an SMSC SCH311%d chip at 0x%04x\n", dev_id, base_addr); + +exit: + sch311x_sio_exit(sio_config_port); + return err; +} + +static int __init sch311x_wdt_init(void) +{ + int err, i, found = 0; + unsigned short addr = 0; + + for (i = 0; !found && sch311x_ioports[i]; i++) + if (sch311x_detect(sch311x_ioports[i], &addr) == 0) + found++; + + if (!found) + return -ENODEV; + + sch311x_wdt_data.runtime_reg = addr; + + err = platform_driver_register(&sch311x_wdt_driver); + if (err) + return err; + + sch311x_wdt_pdev = platform_device_register_simple(DRV_NAME, addr, + NULL, 0); + + if (IS_ERR(sch311x_wdt_pdev)) { + err = PTR_ERR(sch311x_wdt_pdev); + goto unreg_platform_driver; + } + + return 0; + +unreg_platform_driver: + platform_driver_unregister(&sch311x_wdt_driver); + return err; +} + +static void __exit sch311x_wdt_exit(void) +{ + platform_device_unregister(sch311x_wdt_pdev); + platform_driver_unregister(&sch311x_wdt_driver); +} + +module_init(sch311x_wdt_init); +module_exit(sch311x_wdt_exit); + +MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>"); +MODULE_DESCRIPTION("SMSC SCH311x WatchDog Timer Driver"); +MODULE_LICENSE("GPL"); |