Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Driver for the MTX-1 Watchdog. |
| 3 | * |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 4 | * (C) Copyright 2005 4G Systems <info@4g-systems.biz>, |
| 5 | * All Rights Reserved. |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 6 | * http://www.4g-systems.biz |
| 7 | * |
Wim Van Sebroeck | 143a2e5 | 2009-03-18 08:35:09 +0000 | [diff] [blame] | 8 | * (C) Copyright 2007 OpenWrt.org, Florian Fainelli <florian@openwrt.org> |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 9 | * |
| 10 | * This program is free software; you can redistribute it and/or |
| 11 | * modify it under the terms of the GNU General Public License |
| 12 | * as published by the Free Software Foundation; either version |
| 13 | * 2 of the License, or (at your option) any later version. |
| 14 | * |
| 15 | * Neither Michael Stickel nor 4G Systems admit liability nor provide |
| 16 | * warranty for any of this software. This material is provided |
| 17 | * "AS-IS" and at no charge. |
| 18 | * |
| 19 | * (c) Copyright 2005 4G Systems <info@4g-systems.biz> |
| 20 | * |
| 21 | * Release 0.01. |
| 22 | * Author: Michael Stickel michael.stickel@4g-systems.biz |
| 23 | * |
| 24 | * Release 0.02. |
| 25 | * Author: Florian Fainelli florian@openwrt.org |
| 26 | * use the Linux watchdog/timer APIs |
| 27 | * |
| 28 | * The Watchdog is configured to reset the MTX-1 |
| 29 | * if it is not triggered for 100 seconds. |
| 30 | * It should not be triggered more often than 1.6 seconds. |
| 31 | * |
| 32 | * A timer triggers the watchdog every 5 seconds, until |
| 33 | * it is opened for the first time. After the first open |
| 34 | * it MUST be triggered every 2..95 seconds. |
| 35 | */ |
| 36 | |
| 37 | #include <linux/module.h> |
| 38 | #include <linux/moduleparam.h> |
| 39 | #include <linux/types.h> |
| 40 | #include <linux/errno.h> |
| 41 | #include <linux/miscdevice.h> |
| 42 | #include <linux/fs.h> |
| 43 | #include <linux/init.h> |
| 44 | #include <linux/ioport.h> |
| 45 | #include <linux/timer.h> |
| 46 | #include <linux/completion.h> |
| 47 | #include <linux/jiffies.h> |
| 48 | #include <linux/watchdog.h> |
Florian Fainelli | 6ea8115 | 2008-01-07 19:08:49 +0100 | [diff] [blame] | 49 | #include <linux/platform_device.h> |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 50 | #include <linux/io.h> |
| 51 | #include <linux/uaccess.h> |
| 52 | #include <linux/gpio.h> |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 53 | |
| 54 | #include <asm/mach-au1x00/au1000.h> |
| 55 | |
| 56 | #define MTX1_WDT_INTERVAL (5 * HZ) |
| 57 | |
| 58 | static int ticks = 100 * HZ; |
| 59 | |
| 60 | static struct { |
| 61 | struct completion stop; |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 62 | spinlock_t lock; |
Florian Fainelli | 996d62d | 2008-02-25 13:39:57 +0100 | [diff] [blame] | 63 | int running; |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 64 | struct timer_list timer; |
Florian Fainelli | 996d62d | 2008-02-25 13:39:57 +0100 | [diff] [blame] | 65 | int queue; |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 66 | int default_ticks; |
| 67 | unsigned long inuse; |
Florian Fainelli | 6ea8115 | 2008-01-07 19:08:49 +0100 | [diff] [blame] | 68 | unsigned gpio; |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 69 | } mtx1_wdt_device; |
| 70 | |
| 71 | static void mtx1_wdt_trigger(unsigned long unused) |
| 72 | { |
| 73 | u32 tmp; |
| 74 | |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 75 | spin_lock(&mtx1_wdt_device.lock); |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 76 | if (mtx1_wdt_device.running) |
| 77 | ticks--; |
| 78 | /* |
| 79 | * toggle GPIO2_15 |
| 80 | */ |
| 81 | tmp = au_readl(GPIO2_DIR); |
Florian Fainelli | 6ea8115 | 2008-01-07 19:08:49 +0100 | [diff] [blame] | 82 | tmp = (tmp & ~(1 << mtx1_wdt_device.gpio)) | |
| 83 | ((~tmp) & (1 << mtx1_wdt_device.gpio)); |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 84 | au_writel(tmp, GPIO2_DIR); |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 85 | |
| 86 | if (mtx1_wdt_device.queue && ticks) |
| 87 | mod_timer(&mtx1_wdt_device.timer, jiffies + MTX1_WDT_INTERVAL); |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 88 | else |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 89 | complete(&mtx1_wdt_device.stop); |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 90 | spin_unlock(&mtx1_wdt_device.lock); |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 91 | } |
| 92 | |
| 93 | static void mtx1_wdt_reset(void) |
| 94 | { |
| 95 | ticks = mtx1_wdt_device.default_ticks; |
| 96 | } |
| 97 | |
| 98 | |
| 99 | static void mtx1_wdt_start(void) |
| 100 | { |
Florian Fainelli | f80e919 | 2008-10-24 19:52:56 +0200 | [diff] [blame] | 101 | unsigned long flags; |
| 102 | |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 103 | spin_lock_irqsave(&mtx1_wdt_device.lock, flags); |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 104 | if (!mtx1_wdt_device.queue) { |
| 105 | mtx1_wdt_device.queue = 1; |
Florian Fainelli | 6ea8115 | 2008-01-07 19:08:49 +0100 | [diff] [blame] | 106 | gpio_set_value(mtx1_wdt_device.gpio, 1); |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 107 | mod_timer(&mtx1_wdt_device.timer, jiffies + MTX1_WDT_INTERVAL); |
| 108 | } |
| 109 | mtx1_wdt_device.running++; |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 110 | spin_unlock_irqrestore(&mtx1_wdt_device.lock, flags); |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 111 | } |
| 112 | |
| 113 | static int mtx1_wdt_stop(void) |
| 114 | { |
Florian Fainelli | f80e919 | 2008-10-24 19:52:56 +0200 | [diff] [blame] | 115 | unsigned long flags; |
| 116 | |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 117 | spin_lock_irqsave(&mtx1_wdt_device.lock, flags); |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 118 | if (mtx1_wdt_device.queue) { |
| 119 | mtx1_wdt_device.queue = 0; |
Florian Fainelli | 6ea8115 | 2008-01-07 19:08:49 +0100 | [diff] [blame] | 120 | gpio_set_value(mtx1_wdt_device.gpio, 0); |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 121 | } |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 122 | ticks = mtx1_wdt_device.default_ticks; |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 123 | spin_unlock_irqrestore(&mtx1_wdt_device.lock, flags); |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 124 | return 0; |
| 125 | } |
| 126 | |
| 127 | /* Filesystem functions */ |
| 128 | |
| 129 | static int mtx1_wdt_open(struct inode *inode, struct file *file) |
| 130 | { |
| 131 | if (test_and_set_bit(0, &mtx1_wdt_device.inuse)) |
| 132 | return -EBUSY; |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 133 | return nonseekable_open(inode, file); |
| 134 | } |
| 135 | |
| 136 | |
| 137 | static int mtx1_wdt_release(struct inode *inode, struct file *file) |
| 138 | { |
| 139 | clear_bit(0, &mtx1_wdt_device.inuse); |
| 140 | return 0; |
| 141 | } |
| 142 | |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 143 | static long mtx1_wdt_ioctl(struct file *file, unsigned int cmd, |
| 144 | unsigned long arg) |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 145 | { |
| 146 | void __user *argp = (void __user *)arg; |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 147 | int __user *p = (int __user *)argp; |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 148 | unsigned int value; |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 149 | static const struct watchdog_info ident = { |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 150 | .options = WDIOF_CARDRESET, |
| 151 | .identity = "MTX-1 WDT", |
| 152 | }; |
| 153 | |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 154 | switch (cmd) { |
Wim Van Sebroeck | 0c06090c | 2008-07-18 11:41:17 +0000 | [diff] [blame] | 155 | case WDIOC_GETSUPPORT: |
| 156 | if (copy_to_user(argp, &ident, sizeof(ident))) |
| 157 | return -EFAULT; |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 158 | break; |
| 159 | case WDIOC_GETSTATUS: |
| 160 | case WDIOC_GETBOOTSTATUS: |
| 161 | put_user(0, p); |
| 162 | break; |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 163 | case WDIOC_SETOPTIONS: |
| 164 | if (get_user(value, p)) |
| 165 | return -EFAULT; |
| 166 | if (value & WDIOS_ENABLECARD) |
| 167 | mtx1_wdt_start(); |
| 168 | else if (value & WDIOS_DISABLECARD) |
| 169 | mtx1_wdt_stop(); |
| 170 | else |
| 171 | return -EINVAL; |
| 172 | return 0; |
Wim Van Sebroeck | 0c06090c | 2008-07-18 11:41:17 +0000 | [diff] [blame] | 173 | case WDIOC_KEEPALIVE: |
| 174 | mtx1_wdt_reset(); |
| 175 | break; |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 176 | default: |
| 177 | return -ENOTTY; |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 178 | } |
| 179 | return 0; |
| 180 | } |
| 181 | |
| 182 | |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 183 | static ssize_t mtx1_wdt_write(struct file *file, const char *buf, |
| 184 | size_t count, loff_t *ppos) |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 185 | { |
| 186 | if (!count) |
| 187 | return -EIO; |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 188 | mtx1_wdt_reset(); |
| 189 | return count; |
| 190 | } |
| 191 | |
Jan Engelhardt | b47a166 | 2008-01-22 20:48:10 +0100 | [diff] [blame] | 192 | static const struct file_operations mtx1_wdt_fops = { |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 193 | .owner = THIS_MODULE, |
| 194 | .llseek = no_llseek, |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 195 | .unlocked_ioctl = mtx1_wdt_ioctl, |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 196 | .open = mtx1_wdt_open, |
| 197 | .write = mtx1_wdt_write, |
Wim Van Sebroeck | 7944d3a | 2008-08-06 20:19:41 +0000 | [diff] [blame] | 198 | .release = mtx1_wdt_release, |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 199 | }; |
| 200 | |
| 201 | |
| 202 | static struct miscdevice mtx1_wdt_misc = { |
| 203 | .minor = WATCHDOG_MINOR, |
| 204 | .name = "watchdog", |
Wim Van Sebroeck | 7944d3a | 2008-08-06 20:19:41 +0000 | [diff] [blame] | 205 | .fops = &mtx1_wdt_fops, |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 206 | }; |
| 207 | |
| 208 | |
Wim Van Sebroeck | b6bf291 | 2009-04-14 20:30:55 +0000 | [diff] [blame] | 209 | static int __devinit mtx1_wdt_probe(struct platform_device *pdev) |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 210 | { |
| 211 | int ret; |
| 212 | |
Florian Fainelli | 6ea8115 | 2008-01-07 19:08:49 +0100 | [diff] [blame] | 213 | mtx1_wdt_device.gpio = pdev->resource[0].start; |
| 214 | |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 215 | spin_lock_init(&mtx1_wdt_device.lock); |
| 216 | init_completion(&mtx1_wdt_device.stop); |
| 217 | mtx1_wdt_device.queue = 0; |
| 218 | clear_bit(0, &mtx1_wdt_device.inuse); |
| 219 | setup_timer(&mtx1_wdt_device.timer, mtx1_wdt_trigger, 0L); |
| 220 | mtx1_wdt_device.default_ticks = ticks; |
| 221 | |
| 222 | ret = misc_register(&mtx1_wdt_misc); |
| 223 | if (ret < 0) { |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 224 | printk(KERN_ERR " mtx-1_wdt : failed to register\n"); |
| 225 | return ret; |
| 226 | } |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 227 | mtx1_wdt_start(); |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 228 | printk(KERN_INFO "MTX-1 Watchdog driver\n"); |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 229 | return 0; |
| 230 | } |
| 231 | |
Wim Van Sebroeck | b6bf291 | 2009-04-14 20:30:55 +0000 | [diff] [blame] | 232 | static int __devexit mtx1_wdt_remove(struct platform_device *pdev) |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 233 | { |
Alan Cox | ed78c2d | 2008-05-19 14:07:21 +0100 | [diff] [blame] | 234 | /* FIXME: do we need to lock this test ? */ |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 235 | if (mtx1_wdt_device.queue) { |
| 236 | mtx1_wdt_device.queue = 0; |
| 237 | wait_for_completion(&mtx1_wdt_device.stop); |
| 238 | } |
| 239 | misc_deregister(&mtx1_wdt_misc); |
Florian Fainelli | 6ea8115 | 2008-01-07 19:08:49 +0100 | [diff] [blame] | 240 | return 0; |
| 241 | } |
| 242 | |
| 243 | static struct platform_driver mtx1_wdt = { |
| 244 | .probe = mtx1_wdt_probe, |
Wim Van Sebroeck | b6bf291 | 2009-04-14 20:30:55 +0000 | [diff] [blame] | 245 | .remove = __devexit_p(mtx1_wdt_remove), |
Florian Fainelli | 6ea8115 | 2008-01-07 19:08:49 +0100 | [diff] [blame] | 246 | .driver.name = "mtx1-wdt", |
Kay Sievers | f37d193 | 2008-04-10 21:29:23 -0700 | [diff] [blame] | 247 | .driver.owner = THIS_MODULE, |
Florian Fainelli | 6ea8115 | 2008-01-07 19:08:49 +0100 | [diff] [blame] | 248 | }; |
| 249 | |
| 250 | static int __init mtx1_wdt_init(void) |
| 251 | { |
| 252 | return platform_driver_register(&mtx1_wdt); |
| 253 | } |
| 254 | |
| 255 | static void __exit mtx1_wdt_exit(void) |
| 256 | { |
| 257 | platform_driver_unregister(&mtx1_wdt); |
Florian Fainelli | 04bf3b4 | 2007-05-06 12:55:32 +0200 | [diff] [blame] | 258 | } |
| 259 | |
| 260 | module_init(mtx1_wdt_init); |
| 261 | module_exit(mtx1_wdt_exit); |
| 262 | |
| 263 | MODULE_AUTHOR("Michael Stickel, Florian Fainelli"); |
| 264 | MODULE_DESCRIPTION("Driver for the MTX-1 watchdog"); |
| 265 | MODULE_LICENSE("GPL"); |
Florian Fainelli | 6ea8115 | 2008-01-07 19:08:49 +0100 | [diff] [blame] | 266 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |
Kay Sievers | f37d193 | 2008-04-10 21:29:23 -0700 | [diff] [blame] | 267 | MODULE_ALIAS("platform:mtx1-wdt"); |