Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* linux/drivers/char/watchdog/s3c2410_wdt.c |
| 2 | * |
| 3 | * Copyright (c) 2004 Simtec Electronics |
| 4 | * Ben Dooks <ben@simtec.co.uk> |
| 5 | * |
| 6 | * S3C2410 Watchdog Timer Support |
| 7 | * |
| 8 | * Based on, softdog.c by Alan Cox, |
| 9 | * (c) Copyright 1996 Alan Cox <alan@redhat.com> |
| 10 | * |
| 11 | * This program is free software; you can redistribute it and/or modify |
| 12 | * it under the terms of the GNU General Public License as published by |
| 13 | * the Free Software Foundation; either version 2 of the License, or |
| 14 | * (at your option) any later version. |
| 15 | * |
| 16 | * This program is distributed in the hope that it will be useful, |
| 17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 19 | * GNU General Public License for more details. |
| 20 | * |
| 21 | * You should have received a copy of the GNU General Public License |
| 22 | * along with this program; if not, write to the Free Software |
| 23 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 24 | * |
| 25 | * Changelog: |
| 26 | * 05-Oct-2004 BJD Added semaphore init to stop crashes on open |
| 27 | * Fixed tmr_count / wdt_count confusion |
| 28 | * Added configurable debug |
| 29 | * |
Ben Dooks | af4bb82 | 2005-08-17 09:03:23 +0200 | [diff] [blame] | 30 | * 11-Jan-2005 BJD Fixed divide-by-2 in timeout code |
| 31 | * |
| 32 | * 25-Jan-2005 DA Added suspend/resume support |
Ben Dooks | 94f1e9f | 2005-08-17 09:04:52 +0200 | [diff] [blame] | 33 | * Replaced reboot notifier with .shutdown method |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | * |
| 35 | * 10-Mar-2005 LCVR Changed S3C2410_VA to S3C24XX_VA |
| 36 | */ |
| 37 | |
| 38 | #include <linux/module.h> |
| 39 | #include <linux/moduleparam.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | #include <linux/types.h> |
| 41 | #include <linux/timer.h> |
| 42 | #include <linux/miscdevice.h> |
| 43 | #include <linux/watchdog.h> |
| 44 | #include <linux/fs.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 45 | #include <linux/init.h> |
Russell King | d052d1b | 2005-10-29 19:07:23 +0100 | [diff] [blame] | 46 | #include <linux/platform_device.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | #include <linux/interrupt.h> |
Russell King | f8ce254 | 2006-01-07 16:15:52 +0000 | [diff] [blame] | 48 | #include <linux/clk.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 49 | |
| 50 | #include <asm/uaccess.h> |
| 51 | #include <asm/io.h> |
| 52 | |
| 53 | #include <asm/arch/map.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | |
Ben Dooks | b430708 | 2007-07-24 13:28:01 +0100 | [diff] [blame] | 55 | #undef S3C_VA_WATCHDOG |
| 56 | #define S3C_VA_WATCHDOG (0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | |
Ben Dooks | b430708 | 2007-07-24 13:28:01 +0100 | [diff] [blame] | 58 | #include <asm/plat-s3c/regs-watchdog.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 59 | |
| 60 | #define PFX "s3c2410-wdt: " |
| 61 | |
| 62 | #define CONFIG_S3C2410_WATCHDOG_ATBOOT (0) |
| 63 | #define CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME (15) |
| 64 | |
Ben Dooks | 25ff378 | 2006-09-06 12:24:35 +0100 | [diff] [blame] | 65 | static int nowayout = WATCHDOG_NOWAYOUT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | static int tmr_margin = CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME; |
| 67 | static int tmr_atboot = CONFIG_S3C2410_WATCHDOG_ATBOOT; |
| 68 | static int soft_noboot = 0; |
| 69 | static int debug = 0; |
| 70 | |
| 71 | module_param(tmr_margin, int, 0); |
| 72 | module_param(tmr_atboot, int, 0); |
| 73 | module_param(nowayout, int, 0); |
| 74 | module_param(soft_noboot, int, 0); |
| 75 | module_param(debug, int, 0); |
| 76 | |
| 77 | MODULE_PARM_DESC(tmr_margin, "Watchdog tmr_margin in seconds. default=" __MODULE_STRING(CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME) ")"); |
| 78 | |
| 79 | MODULE_PARM_DESC(tmr_atboot, "Watchdog is started at boot time if set to 1, default=" __MODULE_STRING(CONFIG_S3C2410_WATCHDOG_ATBOOT)); |
| 80 | |
Wim Van Sebroeck | bffda5c | 2007-01-27 20:54:24 +0100 | [diff] [blame] | 81 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | |
| 83 | MODULE_PARM_DESC(soft_noboot, "Watchdog action, set to 1 to ignore reboots, 0 to reboot (default depends on ONLY_TESTING)"); |
| 84 | |
| 85 | MODULE_PARM_DESC(debug, "Watchdog debug, set to >1 for debug, (default 0)"); |
| 86 | |
| 87 | |
| 88 | typedef enum close_state { |
| 89 | CLOSE_STATE_NOT, |
| 90 | CLOSE_STATE_ALLOW=0x4021 |
| 91 | } close_state_t; |
| 92 | |
| 93 | static DECLARE_MUTEX(open_lock); |
| 94 | |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 95 | static struct device *wdt_dev; /* platform device attached to */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 96 | static struct resource *wdt_mem; |
| 97 | static struct resource *wdt_irq; |
| 98 | static struct clk *wdt_clock; |
| 99 | static void __iomem *wdt_base; |
| 100 | static unsigned int wdt_count; |
| 101 | static close_state_t allow_close; |
| 102 | |
| 103 | /* watchdog control routines */ |
| 104 | |
| 105 | #define DBG(msg...) do { \ |
| 106 | if (debug) \ |
| 107 | printk(KERN_INFO msg); \ |
| 108 | } while(0) |
| 109 | |
| 110 | /* functions */ |
| 111 | |
| 112 | static int s3c2410wdt_keepalive(void) |
| 113 | { |
| 114 | writel(wdt_count, wdt_base + S3C2410_WTCNT); |
| 115 | return 0; |
| 116 | } |
| 117 | |
| 118 | static int s3c2410wdt_stop(void) |
| 119 | { |
| 120 | unsigned long wtcon; |
| 121 | |
| 122 | wtcon = readl(wdt_base + S3C2410_WTCON); |
| 123 | wtcon &= ~(S3C2410_WTCON_ENABLE | S3C2410_WTCON_RSTEN); |
| 124 | writel(wtcon, wdt_base + S3C2410_WTCON); |
| 125 | |
| 126 | return 0; |
| 127 | } |
| 128 | |
| 129 | static int s3c2410wdt_start(void) |
| 130 | { |
| 131 | unsigned long wtcon; |
| 132 | |
| 133 | s3c2410wdt_stop(); |
| 134 | |
| 135 | wtcon = readl(wdt_base + S3C2410_WTCON); |
| 136 | wtcon |= S3C2410_WTCON_ENABLE | S3C2410_WTCON_DIV128; |
| 137 | |
| 138 | if (soft_noboot) { |
| 139 | wtcon |= S3C2410_WTCON_INTEN; |
| 140 | wtcon &= ~S3C2410_WTCON_RSTEN; |
| 141 | } else { |
| 142 | wtcon &= ~S3C2410_WTCON_INTEN; |
| 143 | wtcon |= S3C2410_WTCON_RSTEN; |
| 144 | } |
| 145 | |
| 146 | DBG("%s: wdt_count=0x%08x, wtcon=%08lx\n", |
| 147 | __FUNCTION__, wdt_count, wtcon); |
| 148 | |
| 149 | writel(wdt_count, wdt_base + S3C2410_WTDAT); |
| 150 | writel(wdt_count, wdt_base + S3C2410_WTCNT); |
| 151 | writel(wtcon, wdt_base + S3C2410_WTCON); |
| 152 | |
| 153 | return 0; |
| 154 | } |
| 155 | |
| 156 | static int s3c2410wdt_set_heartbeat(int timeout) |
| 157 | { |
| 158 | unsigned int freq = clk_get_rate(wdt_clock); |
| 159 | unsigned int count; |
| 160 | unsigned int divisor = 1; |
| 161 | unsigned long wtcon; |
| 162 | |
| 163 | if (timeout < 1) |
| 164 | return -EINVAL; |
| 165 | |
| 166 | freq /= 128; |
| 167 | count = timeout * freq; |
| 168 | |
| 169 | DBG("%s: count=%d, timeout=%d, freq=%d\n", |
| 170 | __FUNCTION__, count, timeout, freq); |
| 171 | |
| 172 | /* if the count is bigger than the watchdog register, |
| 173 | then work out what we need to do (and if) we can |
| 174 | actually make this value |
| 175 | */ |
| 176 | |
| 177 | if (count >= 0x10000) { |
| 178 | for (divisor = 1; divisor <= 0x100; divisor++) { |
| 179 | if ((count / divisor) < 0x10000) |
| 180 | break; |
| 181 | } |
| 182 | |
| 183 | if ((count / divisor) >= 0x10000) { |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 184 | dev_err(wdt_dev, "timeout %d too big\n", timeout); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | return -EINVAL; |
| 186 | } |
| 187 | } |
| 188 | |
| 189 | tmr_margin = timeout; |
| 190 | |
| 191 | DBG("%s: timeout=%d, divisor=%d, count=%d (%08x)\n", |
| 192 | __FUNCTION__, timeout, divisor, count, count/divisor); |
| 193 | |
| 194 | count /= divisor; |
| 195 | wdt_count = count; |
| 196 | |
| 197 | /* update the pre-scaler */ |
| 198 | wtcon = readl(wdt_base + S3C2410_WTCON); |
| 199 | wtcon &= ~S3C2410_WTCON_PRESCALE_MASK; |
| 200 | wtcon |= S3C2410_WTCON_PRESCALE(divisor-1); |
| 201 | |
| 202 | writel(count, wdt_base + S3C2410_WTDAT); |
| 203 | writel(wtcon, wdt_base + S3C2410_WTCON); |
| 204 | |
| 205 | return 0; |
| 206 | } |
| 207 | |
| 208 | /* |
| 209 | * /dev/watchdog handling |
| 210 | */ |
| 211 | |
| 212 | static int s3c2410wdt_open(struct inode *inode, struct file *file) |
| 213 | { |
| 214 | if(down_trylock(&open_lock)) |
| 215 | return -EBUSY; |
| 216 | |
Ben Dooks | 25ff378 | 2006-09-06 12:24:35 +0100 | [diff] [blame] | 217 | if (nowayout) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 218 | __module_get(THIS_MODULE); |
Ben Dooks | 25ff378 | 2006-09-06 12:24:35 +0100 | [diff] [blame] | 219 | |
| 220 | allow_close = CLOSE_STATE_NOT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 221 | |
| 222 | /* start the timer */ |
| 223 | s3c2410wdt_start(); |
| 224 | return nonseekable_open(inode, file); |
| 225 | } |
| 226 | |
| 227 | static int s3c2410wdt_release(struct inode *inode, struct file *file) |
| 228 | { |
| 229 | /* |
| 230 | * Shut off the timer. |
| 231 | * Lock it in if it's a module and we set nowayout |
| 232 | */ |
Ben Dooks | 25ff378 | 2006-09-06 12:24:35 +0100 | [diff] [blame] | 233 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | if (allow_close == CLOSE_STATE_ALLOW) { |
| 235 | s3c2410wdt_stop(); |
| 236 | } else { |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 237 | dev_err(wdt_dev, "Unexpected close, not stopping watchdog\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | s3c2410wdt_keepalive(); |
| 239 | } |
| 240 | |
| 241 | allow_close = CLOSE_STATE_NOT; |
| 242 | up(&open_lock); |
| 243 | return 0; |
| 244 | } |
| 245 | |
| 246 | static ssize_t s3c2410wdt_write(struct file *file, const char __user *data, |
| 247 | size_t len, loff_t *ppos) |
| 248 | { |
| 249 | /* |
| 250 | * Refresh the timer. |
| 251 | */ |
| 252 | if(len) { |
| 253 | if (!nowayout) { |
| 254 | size_t i; |
| 255 | |
| 256 | /* In case it was set long ago */ |
| 257 | allow_close = CLOSE_STATE_NOT; |
| 258 | |
| 259 | for (i = 0; i != len; i++) { |
| 260 | char c; |
| 261 | |
| 262 | if (get_user(c, data + i)) |
| 263 | return -EFAULT; |
| 264 | if (c == 'V') |
| 265 | allow_close = CLOSE_STATE_ALLOW; |
| 266 | } |
| 267 | } |
| 268 | |
| 269 | s3c2410wdt_keepalive(); |
| 270 | } |
| 271 | return len; |
| 272 | } |
| 273 | |
| 274 | #define OPTIONS WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE |
| 275 | |
| 276 | static struct watchdog_info s3c2410_wdt_ident = { |
| 277 | .options = OPTIONS, |
| 278 | .firmware_version = 0, |
| 279 | .identity = "S3C2410 Watchdog", |
| 280 | }; |
| 281 | |
| 282 | |
| 283 | static int s3c2410wdt_ioctl(struct inode *inode, struct file *file, |
| 284 | unsigned int cmd, unsigned long arg) |
| 285 | { |
| 286 | void __user *argp = (void __user *)arg; |
| 287 | int __user *p = argp; |
| 288 | int new_margin; |
| 289 | |
| 290 | switch (cmd) { |
| 291 | default: |
Samuel Tardieu | 795b89d | 2006-09-09 17:34:31 +0200 | [diff] [blame] | 292 | return -ENOTTY; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 293 | |
| 294 | case WDIOC_GETSUPPORT: |
| 295 | return copy_to_user(argp, &s3c2410_wdt_ident, |
| 296 | sizeof(s3c2410_wdt_ident)) ? -EFAULT : 0; |
| 297 | |
| 298 | case WDIOC_GETSTATUS: |
| 299 | case WDIOC_GETBOOTSTATUS: |
| 300 | return put_user(0, p); |
| 301 | |
| 302 | case WDIOC_KEEPALIVE: |
| 303 | s3c2410wdt_keepalive(); |
| 304 | return 0; |
| 305 | |
| 306 | case WDIOC_SETTIMEOUT: |
| 307 | if (get_user(new_margin, p)) |
| 308 | return -EFAULT; |
| 309 | |
| 310 | if (s3c2410wdt_set_heartbeat(new_margin)) |
| 311 | return -EINVAL; |
| 312 | |
| 313 | s3c2410wdt_keepalive(); |
| 314 | return put_user(tmr_margin, p); |
| 315 | |
| 316 | case WDIOC_GETTIMEOUT: |
| 317 | return put_user(tmr_margin, p); |
| 318 | } |
| 319 | } |
| 320 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | /* kernel interface */ |
| 322 | |
Arjan van de Ven | 62322d2 | 2006-07-03 00:24:21 -0700 | [diff] [blame] | 323 | static const struct file_operations s3c2410wdt_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 324 | .owner = THIS_MODULE, |
| 325 | .llseek = no_llseek, |
| 326 | .write = s3c2410wdt_write, |
| 327 | .ioctl = s3c2410wdt_ioctl, |
| 328 | .open = s3c2410wdt_open, |
| 329 | .release = s3c2410wdt_release, |
| 330 | }; |
| 331 | |
| 332 | static struct miscdevice s3c2410wdt_miscdev = { |
| 333 | .minor = WATCHDOG_MINOR, |
| 334 | .name = "watchdog", |
| 335 | .fops = &s3c2410wdt_fops, |
| 336 | }; |
| 337 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 338 | /* interrupt handler code */ |
| 339 | |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 340 | static irqreturn_t s3c2410wdt_irq(int irqno, void *param) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 341 | { |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 342 | dev_info(wdt_dev, "watchdog timer expired (irq)\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 343 | |
| 344 | s3c2410wdt_keepalive(); |
| 345 | return IRQ_HANDLED; |
| 346 | } |
| 347 | /* device interface */ |
| 348 | |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 349 | static int s3c2410wdt_probe(struct platform_device *pdev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 350 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 351 | struct resource *res; |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 352 | struct device *dev; |
Ben Dooks | 46b814d | 2007-06-14 12:08:54 +0100 | [diff] [blame] | 353 | unsigned int wtcon; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 354 | int started = 0; |
| 355 | int ret; |
| 356 | int size; |
| 357 | |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 358 | DBG("%s: probe=%p\n", __FUNCTION__, pdev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 359 | |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 360 | dev = &pdev->dev; |
| 361 | wdt_dev = &pdev->dev; |
| 362 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 363 | /* get the memory region for the watchdog timer */ |
| 364 | |
| 365 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 366 | if (res == NULL) { |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 367 | dev_err(dev, "no memory resource specified\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 368 | return -ENOENT; |
| 369 | } |
| 370 | |
| 371 | size = (res->end-res->start)+1; |
| 372 | wdt_mem = request_mem_region(res->start, size, pdev->name); |
| 373 | if (wdt_mem == NULL) { |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 374 | dev_err(dev, "failed to get memory region\n"); |
Ben Dooks | 0b6dd8a | 2006-12-18 10:31:32 +0000 | [diff] [blame] | 375 | ret = -ENOENT; |
| 376 | goto err_req; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 377 | } |
| 378 | |
| 379 | wdt_base = ioremap(res->start, size); |
| 380 | if (wdt_base == 0) { |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 381 | dev_err(dev, "failed to ioremap() region\n"); |
Ben Dooks | 0b6dd8a | 2006-12-18 10:31:32 +0000 | [diff] [blame] | 382 | ret = -EINVAL; |
| 383 | goto err_req; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 384 | } |
| 385 | |
| 386 | DBG("probe: mapped wdt_base=%p\n", wdt_base); |
| 387 | |
Arnaud Patard | 62be0741 | 2007-05-05 15:53:15 +0200 | [diff] [blame] | 388 | wdt_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); |
| 389 | if (wdt_irq == NULL) { |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 390 | dev_err(dev, "no irq resource specified\n"); |
Ben Dooks | 0b6dd8a | 2006-12-18 10:31:32 +0000 | [diff] [blame] | 391 | ret = -ENOENT; |
| 392 | goto err_map; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 393 | } |
| 394 | |
Arnaud Patard | 62be0741 | 2007-05-05 15:53:15 +0200 | [diff] [blame] | 395 | ret = request_irq(wdt_irq->start, s3c2410wdt_irq, 0, pdev->name, pdev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 396 | if (ret != 0) { |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 397 | dev_err(dev, "failed to install irq (%d)\n", ret); |
Ben Dooks | 0b6dd8a | 2006-12-18 10:31:32 +0000 | [diff] [blame] | 398 | goto err_map; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 399 | } |
| 400 | |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 401 | wdt_clock = clk_get(&pdev->dev, "watchdog"); |
Akinobu Mita | 9cd4461 | 2006-12-19 17:51:44 +0900 | [diff] [blame] | 402 | if (IS_ERR(wdt_clock)) { |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 403 | dev_err(dev, "failed to find watchdog clock source\n"); |
Akinobu Mita | 9cd4461 | 2006-12-19 17:51:44 +0900 | [diff] [blame] | 404 | ret = PTR_ERR(wdt_clock); |
Ben Dooks | 0b6dd8a | 2006-12-18 10:31:32 +0000 | [diff] [blame] | 405 | goto err_irq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | } |
| 407 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 408 | clk_enable(wdt_clock); |
| 409 | |
| 410 | /* see if we can actually set the requested timer margin, and if |
| 411 | * not, try the default value */ |
| 412 | |
| 413 | if (s3c2410wdt_set_heartbeat(tmr_margin)) { |
| 414 | started = s3c2410wdt_set_heartbeat(CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME); |
| 415 | |
| 416 | if (started == 0) { |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 417 | dev_info(dev,"tmr_margin value out of range, default %d used\n", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 418 | CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME); |
| 419 | } else { |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 420 | dev_info(dev, "default timer value is out of range, cannot start\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 421 | } |
| 422 | } |
| 423 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 424 | ret = misc_register(&s3c2410wdt_miscdev); |
| 425 | if (ret) { |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 426 | dev_err(dev, "cannot register miscdev on minor=%d (%d)\n", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 427 | WATCHDOG_MINOR, ret); |
Ben Dooks | 0b6dd8a | 2006-12-18 10:31:32 +0000 | [diff] [blame] | 428 | goto err_clk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 429 | } |
| 430 | |
| 431 | if (tmr_atboot && started == 0) { |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 432 | dev_info(dev, "starting watchdog timer\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | s3c2410wdt_start(); |
Ben Dooks | 655516c | 2006-04-19 23:02:56 +0100 | [diff] [blame] | 434 | } else if (!tmr_atboot) { |
| 435 | /* if we're not enabling the watchdog, then ensure it is |
| 436 | * disabled if it has been left running from the bootloader |
| 437 | * or other source */ |
| 438 | |
| 439 | s3c2410wdt_stop(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 440 | } |
| 441 | |
Ben Dooks | 46b814d | 2007-06-14 12:08:54 +0100 | [diff] [blame] | 442 | /* print out a statement of readiness */ |
| 443 | |
| 444 | wtcon = readl(wdt_base + S3C2410_WTCON); |
| 445 | |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 446 | dev_info(dev, "watchdog %sactive, reset %sabled, irq %sabled\n", |
Ben Dooks | 46b814d | 2007-06-14 12:08:54 +0100 | [diff] [blame] | 447 | (wtcon & S3C2410_WTCON_ENABLE) ? "" : "in", |
| 448 | (wtcon & S3C2410_WTCON_RSTEN) ? "" : "dis", |
| 449 | (wtcon & S3C2410_WTCON_INTEN) ? "" : "en"); |
Ben Dooks | e8ef92b | 2007-06-14 12:08:55 +0100 | [diff] [blame] | 450 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 451 | return 0; |
Ben Dooks | 0b6dd8a | 2006-12-18 10:31:32 +0000 | [diff] [blame] | 452 | |
| 453 | err_clk: |
| 454 | clk_disable(wdt_clock); |
| 455 | clk_put(wdt_clock); |
| 456 | |
| 457 | err_irq: |
| 458 | free_irq(wdt_irq->start, pdev); |
| 459 | |
| 460 | err_map: |
| 461 | iounmap(wdt_base); |
| 462 | |
| 463 | err_req: |
| 464 | release_resource(wdt_mem); |
| 465 | kfree(wdt_mem); |
| 466 | |
| 467 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 468 | } |
| 469 | |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 470 | static int s3c2410wdt_remove(struct platform_device *dev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 471 | { |
Ben Dooks | 0b6dd8a | 2006-12-18 10:31:32 +0000 | [diff] [blame] | 472 | release_resource(wdt_mem); |
| 473 | kfree(wdt_mem); |
| 474 | wdt_mem = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 475 | |
Ben Dooks | 0b6dd8a | 2006-12-18 10:31:32 +0000 | [diff] [blame] | 476 | free_irq(wdt_irq->start, dev); |
| 477 | wdt_irq = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 478 | |
Ben Dooks | 0b6dd8a | 2006-12-18 10:31:32 +0000 | [diff] [blame] | 479 | clk_disable(wdt_clock); |
| 480 | clk_put(wdt_clock); |
| 481 | wdt_clock = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 482 | |
Amol Lad | e34477e | 2006-10-06 13:41:12 -0700 | [diff] [blame] | 483 | iounmap(wdt_base); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 484 | misc_deregister(&s3c2410wdt_miscdev); |
| 485 | return 0; |
| 486 | } |
| 487 | |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 488 | static void s3c2410wdt_shutdown(struct platform_device *dev) |
Ben Dooks | 94f1e9f | 2005-08-17 09:04:52 +0200 | [diff] [blame] | 489 | { |
| 490 | s3c2410wdt_stop(); |
| 491 | } |
| 492 | |
Ben Dooks | af4bb82 | 2005-08-17 09:03:23 +0200 | [diff] [blame] | 493 | #ifdef CONFIG_PM |
| 494 | |
| 495 | static unsigned long wtcon_save; |
| 496 | static unsigned long wtdat_save; |
| 497 | |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 498 | static int s3c2410wdt_suspend(struct platform_device *dev, pm_message_t state) |
Ben Dooks | af4bb82 | 2005-08-17 09:03:23 +0200 | [diff] [blame] | 499 | { |
Russell King | 9480e30 | 2005-10-28 09:52:56 -0700 | [diff] [blame] | 500 | /* Save watchdog state, and turn it off. */ |
| 501 | wtcon_save = readl(wdt_base + S3C2410_WTCON); |
| 502 | wtdat_save = readl(wdt_base + S3C2410_WTDAT); |
Ben Dooks | af4bb82 | 2005-08-17 09:03:23 +0200 | [diff] [blame] | 503 | |
Russell King | 9480e30 | 2005-10-28 09:52:56 -0700 | [diff] [blame] | 504 | /* Note that WTCNT doesn't need to be saved. */ |
| 505 | s3c2410wdt_stop(); |
Ben Dooks | af4bb82 | 2005-08-17 09:03:23 +0200 | [diff] [blame] | 506 | |
| 507 | return 0; |
| 508 | } |
| 509 | |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 510 | static int s3c2410wdt_resume(struct platform_device *dev) |
Ben Dooks | af4bb82 | 2005-08-17 09:03:23 +0200 | [diff] [blame] | 511 | { |
Russell King | 9480e30 | 2005-10-28 09:52:56 -0700 | [diff] [blame] | 512 | /* Restore watchdog state. */ |
Ben Dooks | af4bb82 | 2005-08-17 09:03:23 +0200 | [diff] [blame] | 513 | |
Russell King | 9480e30 | 2005-10-28 09:52:56 -0700 | [diff] [blame] | 514 | writel(wtdat_save, wdt_base + S3C2410_WTDAT); |
| 515 | writel(wtdat_save, wdt_base + S3C2410_WTCNT); /* Reset count */ |
| 516 | writel(wtcon_save, wdt_base + S3C2410_WTCON); |
Ben Dooks | af4bb82 | 2005-08-17 09:03:23 +0200 | [diff] [blame] | 517 | |
Russell King | 9480e30 | 2005-10-28 09:52:56 -0700 | [diff] [blame] | 518 | printk(KERN_INFO PFX "watchdog %sabled\n", |
| 519 | (wtcon_save & S3C2410_WTCON_ENABLE) ? "en" : "dis"); |
Ben Dooks | af4bb82 | 2005-08-17 09:03:23 +0200 | [diff] [blame] | 520 | |
| 521 | return 0; |
| 522 | } |
| 523 | |
| 524 | #else |
| 525 | #define s3c2410wdt_suspend NULL |
| 526 | #define s3c2410wdt_resume NULL |
| 527 | #endif /* CONFIG_PM */ |
| 528 | |
| 529 | |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 530 | static struct platform_driver s3c2410wdt_driver = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 531 | .probe = s3c2410wdt_probe, |
| 532 | .remove = s3c2410wdt_remove, |
Ben Dooks | 94f1e9f | 2005-08-17 09:04:52 +0200 | [diff] [blame] | 533 | .shutdown = s3c2410wdt_shutdown, |
Ben Dooks | af4bb82 | 2005-08-17 09:03:23 +0200 | [diff] [blame] | 534 | .suspend = s3c2410wdt_suspend, |
| 535 | .resume = s3c2410wdt_resume, |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 536 | .driver = { |
| 537 | .owner = THIS_MODULE, |
| 538 | .name = "s3c2410-wdt", |
| 539 | }, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 540 | }; |
| 541 | |
| 542 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 543 | static char banner[] __initdata = KERN_INFO "S3C2410 Watchdog Timer, (c) 2004 Simtec Electronics\n"; |
| 544 | |
| 545 | static int __init watchdog_init(void) |
| 546 | { |
| 547 | printk(banner); |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 548 | return platform_driver_register(&s3c2410wdt_driver); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 549 | } |
| 550 | |
| 551 | static void __exit watchdog_exit(void) |
| 552 | { |
Russell King | 3ae5eae | 2005-11-09 22:32:44 +0000 | [diff] [blame] | 553 | platform_driver_unregister(&s3c2410wdt_driver); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 554 | } |
| 555 | |
| 556 | module_init(watchdog_init); |
| 557 | module_exit(watchdog_exit); |
| 558 | |
Ben Dooks | af4bb82 | 2005-08-17 09:03:23 +0200 | [diff] [blame] | 559 | MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>, " |
| 560 | "Dimitry Andric <dimitry.andric@tomtom.com>"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 561 | MODULE_DESCRIPTION("S3C2410 Watchdog Device Driver"); |
| 562 | MODULE_LICENSE("GPL"); |
| 563 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |