Blame view
drivers/watchdog/m54xx_wdt.c
5.21 KB
88cce4276 watchdog: Add MCF... |
1 |
/* |
9b9c63ff1 m68knommu: fix m5... |
2 |
* drivers/watchdog/m54xx_wdt.c |
88cce4276 watchdog: Add MCF... |
3 |
* |
9b9c63ff1 m68knommu: fix m5... |
4 |
* Watchdog driver for ColdFire MCF547x & MCF548x processors |
88cce4276 watchdog: Add MCF... |
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 |
* Copyright 2010 (c) Philippe De Muyter <phdm@macqel.be> * * Adapted from the IXP4xx watchdog driver, which carries these notices: * * Author: Deepak Saxena <dsaxena@plexity.net> * * Copyright 2004 (c) MontaVista, Software, Inc. * Based on sa1100 driver, Copyright (C) 2000 Oleg Drokin <green@crimea.edu> * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. */ #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/fs.h> #include <linux/miscdevice.h> #include <linux/watchdog.h> #include <linux/init.h> #include <linux/bitops.h> #include <linux/ioport.h> #include <linux/uaccess.h> #include <asm/coldfire.h> |
9b9c63ff1 m68knommu: fix m5... |
32 33 |
#include <asm/m54xxsim.h> #include <asm/m54xxgpt.h> |
88cce4276 watchdog: Add MCF... |
34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 |
static int nowayout = WATCHDOG_NOWAYOUT; static unsigned int heartbeat = 30; /* (secs) Default is 0.5 minute */ static unsigned long wdt_status; #define WDT_IN_USE 0 #define WDT_OK_TO_CLOSE 1 static void wdt_enable(void) { unsigned int gms0; /* preserve GPIO usage, if any */ gms0 = __raw_readl(MCF_MBAR + MCF_GPT_GMS0); if (gms0 & MCF_GPT_GMS_TMS_GPIO) gms0 &= (MCF_GPT_GMS_TMS_GPIO | MCF_GPT_GMS_GPIO_MASK | MCF_GPT_GMS_OD); else gms0 = MCF_GPT_GMS_TMS_GPIO | MCF_GPT_GMS_OD; __raw_writel(gms0, MCF_MBAR + MCF_GPT_GMS0); __raw_writel(MCF_GPT_GCIR_PRE(heartbeat*(MCF_BUSCLK/0xffff)) | MCF_GPT_GCIR_CNT(0xffff), MCF_MBAR + MCF_GPT_GCIR0); gms0 |= MCF_GPT_GMS_OCPW(0xA5) | MCF_GPT_GMS_WDEN | MCF_GPT_GMS_CE; __raw_writel(gms0, MCF_MBAR + MCF_GPT_GMS0); } static void wdt_disable(void) { unsigned int gms0; /* disable watchdog */ gms0 = __raw_readl(MCF_MBAR + MCF_GPT_GMS0); gms0 &= ~(MCF_GPT_GMS_WDEN | MCF_GPT_GMS_CE); __raw_writel(gms0, MCF_MBAR + MCF_GPT_GMS0); } static void wdt_keepalive(void) { unsigned int gms0; gms0 = __raw_readl(MCF_MBAR + MCF_GPT_GMS0); gms0 |= MCF_GPT_GMS_OCPW(0xA5); __raw_writel(gms0, MCF_MBAR + MCF_GPT_GMS0); } |
9b9c63ff1 m68knommu: fix m5... |
78 |
static int m54xx_wdt_open(struct inode *inode, struct file *file) |
88cce4276 watchdog: Add MCF... |
79 80 81 82 83 84 85 86 |
{ if (test_and_set_bit(WDT_IN_USE, &wdt_status)) return -EBUSY; clear_bit(WDT_OK_TO_CLOSE, &wdt_status); wdt_enable(); return nonseekable_open(inode, file); } |
9b9c63ff1 m68knommu: fix m5... |
87 |
static ssize_t m54xx_wdt_write(struct file *file, const char *data, |
88cce4276 watchdog: Add MCF... |
88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 |
size_t len, loff_t *ppos) { if (len) { if (!nowayout) { size_t i; clear_bit(WDT_OK_TO_CLOSE, &wdt_status); for (i = 0; i != len; i++) { char c; if (get_user(c, data + i)) return -EFAULT; if (c == 'V') set_bit(WDT_OK_TO_CLOSE, &wdt_status); } } wdt_keepalive(); } return len; } static const struct watchdog_info ident = { .options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, |
9b9c63ff1 m68knommu: fix m5... |
113 |
.identity = "Coldfire M54xx Watchdog", |
88cce4276 watchdog: Add MCF... |
114 |
}; |
9b9c63ff1 m68knommu: fix m5... |
115 |
static long m54xx_wdt_ioctl(struct file *file, unsigned int cmd, |
88cce4276 watchdog: Add MCF... |
116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 |
unsigned long arg) { int ret = -ENOTTY; int time; switch (cmd) { case WDIOC_GETSUPPORT: ret = copy_to_user((struct watchdog_info *)arg, &ident, sizeof(ident)) ? -EFAULT : 0; break; case WDIOC_GETSTATUS: ret = put_user(0, (int *)arg); break; case WDIOC_GETBOOTSTATUS: ret = put_user(0, (int *)arg); break; case WDIOC_KEEPALIVE: wdt_keepalive(); ret = 0; break; case WDIOC_SETTIMEOUT: ret = get_user(time, (int *)arg); if (ret) break; if (time <= 0 || time > 30) { ret = -EINVAL; break; } heartbeat = time; wdt_enable(); /* Fall through */ case WDIOC_GETTIMEOUT: ret = put_user(heartbeat, (int *)arg); break; } return ret; } |
9b9c63ff1 m68knommu: fix m5... |
160 |
static int m54xx_wdt_release(struct inode *inode, struct file *file) |
88cce4276 watchdog: Add MCF... |
161 162 163 164 165 166 167 168 169 170 171 172 173 174 |
{ if (test_bit(WDT_OK_TO_CLOSE, &wdt_status)) wdt_disable(); else { printk(KERN_CRIT "WATCHDOG: Device closed unexpectedly - " "timer will not stop "); wdt_keepalive(); } clear_bit(WDT_IN_USE, &wdt_status); clear_bit(WDT_OK_TO_CLOSE, &wdt_status); return 0; } |
9b9c63ff1 m68knommu: fix m5... |
175 |
static const struct file_operations m54xx_wdt_fops = { |
88cce4276 watchdog: Add MCF... |
176 177 |
.owner = THIS_MODULE, .llseek = no_llseek, |
9b9c63ff1 m68knommu: fix m5... |
178 179 180 181 |
.write = m54xx_wdt_write, .unlocked_ioctl = m54xx_wdt_ioctl, .open = m54xx_wdt_open, .release = m54xx_wdt_release, |
88cce4276 watchdog: Add MCF... |
182 |
}; |
9b9c63ff1 m68knommu: fix m5... |
183 |
static struct miscdevice m54xx_wdt_miscdev = { |
88cce4276 watchdog: Add MCF... |
184 185 |
.minor = WATCHDOG_MINOR, .name = "watchdog", |
9b9c63ff1 m68knommu: fix m5... |
186 |
.fops = &m54xx_wdt_fops, |
88cce4276 watchdog: Add MCF... |
187 |
}; |
9b9c63ff1 m68knommu: fix m5... |
188 |
static int __init m54xx_wdt_init(void) |
88cce4276 watchdog: Add MCF... |
189 190 |
{ if (!request_mem_region(MCF_MBAR + MCF_GPT_GCIR0, 4, |
9b9c63ff1 m68knommu: fix m5... |
191 |
"Coldfire M54xx Watchdog")) { |
88cce4276 watchdog: Add MCF... |
192 |
printk(KERN_WARNING |
9b9c63ff1 m68knommu: fix m5... |
193 194 |
"Coldfire M54xx Watchdog : I/O region busy "); |
88cce4276 watchdog: Add MCF... |
195 196 197 198 |
return -EBUSY; } printk(KERN_INFO "ColdFire watchdog driver is loaded. "); |
9b9c63ff1 m68knommu: fix m5... |
199 |
return misc_register(&m54xx_wdt_miscdev); |
88cce4276 watchdog: Add MCF... |
200 |
} |
9b9c63ff1 m68knommu: fix m5... |
201 |
static void __exit m54xx_wdt_exit(void) |
88cce4276 watchdog: Add MCF... |
202 |
{ |
9b9c63ff1 m68knommu: fix m5... |
203 |
misc_deregister(&m54xx_wdt_miscdev); |
88cce4276 watchdog: Add MCF... |
204 205 |
release_mem_region(MCF_MBAR + MCF_GPT_GCIR0, 4); } |
9b9c63ff1 m68knommu: fix m5... |
206 207 |
module_init(m54xx_wdt_init); module_exit(m54xx_wdt_exit); |
88cce4276 watchdog: Add MCF... |
208 209 |
MODULE_AUTHOR("Philippe De Muyter <phdm@macqel.be>"); |
9b9c63ff1 m68knommu: fix m5... |
210 |
MODULE_DESCRIPTION("Coldfire M54xx Watchdog"); |
88cce4276 watchdog: Add MCF... |
211 212 213 214 215 216 217 218 219 |
module_param(heartbeat, int, 0); MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds (default 30s)"); module_param(nowayout, int, 0); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started"); MODULE_LICENSE("GPL"); MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |