Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 1 | /* |
| 2 | * drivers/char/watchdog/pnx4008_wdt.c |
| 3 | * |
| 4 | * Watchdog driver for PNX4008 board |
| 5 | * |
| 6 | * Authors: Dmitry Chigirev <source@mvista.com>, |
| 7 | * Vitaly Wool <vitalywool@gmail.com> |
| 8 | * Based on sa1100 driver, |
| 9 | * Copyright (C) 2000 Oleg Drokin <green@crimea.edu> |
| 10 | * |
| 11 | * 2005-2006 (c) MontaVista Software, Inc. This file is licensed under |
| 12 | * the terms of the GNU General Public License version 2. This program |
| 13 | * is licensed "as is" without any warranty of any kind, whether express |
| 14 | * or implied. |
| 15 | */ |
| 16 | |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 17 | #include <linux/module.h> |
| 18 | #include <linux/moduleparam.h> |
| 19 | #include <linux/types.h> |
| 20 | #include <linux/kernel.h> |
| 21 | #include <linux/fs.h> |
| 22 | #include <linux/miscdevice.h> |
| 23 | #include <linux/watchdog.h> |
| 24 | #include <linux/init.h> |
| 25 | #include <linux/bitops.h> |
| 26 | #include <linux/ioport.h> |
| 27 | #include <linux/device.h> |
| 28 | #include <linux/platform_device.h> |
| 29 | #include <linux/clk.h> |
Wim Van Sebroeck | 99d2853 | 2006-09-10 12:48:15 +0200 | [diff] [blame] | 30 | #include <linux/spinlock.h> |
Alan Cox | 84ca995 | 2008-05-19 14:07:48 +0100 | [diff] [blame] | 31 | #include <linux/uaccess.h> |
| 32 | #include <linux/io.h> |
Russell King | a09e64f | 2008-08-05 16:14:15 +0100 | [diff] [blame] | 33 | #include <mach/hardware.h> |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 34 | |
| 35 | #define MODULE_NAME "PNX4008-WDT: " |
| 36 | |
| 37 | /* WatchDog Timer - Chapter 23 Page 207 */ |
| 38 | |
| 39 | #define DEFAULT_HEARTBEAT 19 |
| 40 | #define MAX_HEARTBEAT 60 |
| 41 | |
| 42 | /* Watchdog timer register set definition */ |
| 43 | #define WDTIM_INT(p) ((p) + 0x0) |
| 44 | #define WDTIM_CTRL(p) ((p) + 0x4) |
| 45 | #define WDTIM_COUNTER(p) ((p) + 0x8) |
| 46 | #define WDTIM_MCTRL(p) ((p) + 0xC) |
| 47 | #define WDTIM_MATCH0(p) ((p) + 0x10) |
| 48 | #define WDTIM_EMR(p) ((p) + 0x14) |
| 49 | #define WDTIM_PULSE(p) ((p) + 0x18) |
| 50 | #define WDTIM_RES(p) ((p) + 0x1C) |
| 51 | |
| 52 | /* WDTIM_INT bit definitions */ |
| 53 | #define MATCH_INT 1 |
| 54 | |
| 55 | /* WDTIM_CTRL bit definitions */ |
| 56 | #define COUNT_ENAB 1 |
Wim Van Sebroeck | 143a2e5 | 2009-03-18 08:35:09 +0000 | [diff] [blame] | 57 | #define RESET_COUNT (1 << 1) |
| 58 | #define DEBUG_EN (1 << 2) |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 59 | |
| 60 | /* WDTIM_MCTRL bit definitions */ |
| 61 | #define MR0_INT 1 |
| 62 | #undef RESET_COUNT0 |
Wim Van Sebroeck | 143a2e5 | 2009-03-18 08:35:09 +0000 | [diff] [blame] | 63 | #define RESET_COUNT0 (1 << 2) |
| 64 | #define STOP_COUNT0 (1 << 2) |
| 65 | #define M_RES1 (1 << 3) |
| 66 | #define M_RES2 (1 << 4) |
| 67 | #define RESFRC1 (1 << 5) |
| 68 | #define RESFRC2 (1 << 6) |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 69 | |
| 70 | /* WDTIM_EMR bit definitions */ |
| 71 | #define EXT_MATCH0 1 |
Wim Van Sebroeck | 143a2e5 | 2009-03-18 08:35:09 +0000 | [diff] [blame] | 72 | #define MATCH_OUTPUT_HIGH (2 << 4) /*a MATCH_CTRL setting */ |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 73 | |
| 74 | /* WDTIM_RES bit definitions */ |
| 75 | #define WDOG_RESET 1 /* read only */ |
| 76 | |
| 77 | #define WDOG_COUNTER_RATE 13000000 /*the counter clock is 13 MHz fixed */ |
| 78 | |
Wim Van Sebroeck | 2898172 | 2006-07-03 09:03:47 +0200 | [diff] [blame] | 79 | static int nowayout = WATCHDOG_NOWAYOUT; |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 80 | static int heartbeat = DEFAULT_HEARTBEAT; |
| 81 | |
Alexey Dobriyan | c7dfd0c | 2007-11-01 16:27:08 -0700 | [diff] [blame] | 82 | static DEFINE_SPINLOCK(io_lock); |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 83 | static unsigned long wdt_status; |
| 84 | #define WDT_IN_USE 0 |
| 85 | #define WDT_OK_TO_CLOSE 1 |
| 86 | #define WDT_REGION_INITED 2 |
| 87 | #define WDT_DEVICE_INITED 3 |
| 88 | |
| 89 | static unsigned long boot_status; |
| 90 | |
| 91 | static struct resource *wdt_mem; |
| 92 | static void __iomem *wdt_base; |
| 93 | struct clk *wdt_clk; |
| 94 | |
| 95 | static void wdt_enable(void) |
| 96 | { |
Wim Van Sebroeck | 99d2853 | 2006-09-10 12:48:15 +0200 | [diff] [blame] | 97 | spin_lock(&io_lock); |
| 98 | |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 99 | /* stop counter, initiate counter reset */ |
| 100 | __raw_writel(RESET_COUNT, WDTIM_CTRL(wdt_base)); |
| 101 | /*wait for reset to complete. 100% guarantee event */ |
Vitaly Wool | 65a64ec | 2006-09-11 14:42:39 +0400 | [diff] [blame] | 102 | while (__raw_readl(WDTIM_COUNTER(wdt_base))) |
| 103 | cpu_relax(); |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 104 | /* internal and external reset, stop after that */ |
| 105 | __raw_writel(M_RES2 | STOP_COUNT0 | RESET_COUNT0, |
| 106 | WDTIM_MCTRL(wdt_base)); |
| 107 | /* configure match output */ |
| 108 | __raw_writel(MATCH_OUTPUT_HIGH, WDTIM_EMR(wdt_base)); |
| 109 | /* clear interrupt, just in case */ |
| 110 | __raw_writel(MATCH_INT, WDTIM_INT(wdt_base)); |
| 111 | /* the longest pulse period 65541/(13*10^6) seconds ~ 5 ms. */ |
| 112 | __raw_writel(0xFFFF, WDTIM_PULSE(wdt_base)); |
| 113 | __raw_writel(heartbeat * WDOG_COUNTER_RATE, WDTIM_MATCH0(wdt_base)); |
| 114 | /*enable counter, stop when debugger active */ |
| 115 | __raw_writel(COUNT_ENAB | DEBUG_EN, WDTIM_CTRL(wdt_base)); |
Wim Van Sebroeck | 99d2853 | 2006-09-10 12:48:15 +0200 | [diff] [blame] | 116 | |
| 117 | spin_unlock(&io_lock); |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 118 | } |
| 119 | |
| 120 | static void wdt_disable(void) |
| 121 | { |
Wim Van Sebroeck | 99d2853 | 2006-09-10 12:48:15 +0200 | [diff] [blame] | 122 | spin_lock(&io_lock); |
| 123 | |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 124 | __raw_writel(0, WDTIM_CTRL(wdt_base)); /*stop counter */ |
Wim Van Sebroeck | 99d2853 | 2006-09-10 12:48:15 +0200 | [diff] [blame] | 125 | |
| 126 | spin_unlock(&io_lock); |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 127 | } |
| 128 | |
| 129 | static int pnx4008_wdt_open(struct inode *inode, struct file *file) |
| 130 | { |
Russell King | 24fd1ed | 2009-11-20 13:04:14 +0000 | [diff] [blame] | 131 | int ret; |
| 132 | |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 133 | if (test_and_set_bit(WDT_IN_USE, &wdt_status)) |
| 134 | return -EBUSY; |
| 135 | |
| 136 | clear_bit(WDT_OK_TO_CLOSE, &wdt_status); |
| 137 | |
Russell King | 24fd1ed | 2009-11-20 13:04:14 +0000 | [diff] [blame] | 138 | ret = clk_enable(wdt_clk); |
| 139 | if (ret) { |
| 140 | clear_bit(WDT_IN_USE, &wdt_status); |
| 141 | return ret; |
| 142 | } |
| 143 | |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 144 | wdt_enable(); |
| 145 | |
| 146 | return nonseekable_open(inode, file); |
| 147 | } |
| 148 | |
Alan Cox | 84ca995 | 2008-05-19 14:07:48 +0100 | [diff] [blame] | 149 | static ssize_t pnx4008_wdt_write(struct file *file, const char *data, |
| 150 | size_t len, loff_t *ppos) |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 151 | { |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 152 | if (len) { |
| 153 | if (!nowayout) { |
| 154 | size_t i; |
| 155 | |
| 156 | clear_bit(WDT_OK_TO_CLOSE, &wdt_status); |
| 157 | |
| 158 | for (i = 0; i != len; i++) { |
| 159 | char c; |
| 160 | |
| 161 | if (get_user(c, data + i)) |
| 162 | return -EFAULT; |
| 163 | if (c == 'V') |
| 164 | set_bit(WDT_OK_TO_CLOSE, &wdt_status); |
| 165 | } |
| 166 | } |
| 167 | wdt_enable(); |
| 168 | } |
| 169 | |
| 170 | return len; |
| 171 | } |
| 172 | |
Alan Cox | 84ca995 | 2008-05-19 14:07:48 +0100 | [diff] [blame] | 173 | static const struct watchdog_info ident = { |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 174 | .options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE | |
| 175 | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, |
| 176 | .identity = "PNX4008 Watchdog", |
| 177 | }; |
| 178 | |
Wim Van Sebroeck | 7275fc8 | 2008-09-18 12:26:15 +0000 | [diff] [blame] | 179 | static long pnx4008_wdt_ioctl(struct file *file, unsigned int cmd, |
| 180 | unsigned long arg) |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 181 | { |
Wim Van Sebroeck | f311896 | 2006-09-13 21:27:29 +0200 | [diff] [blame] | 182 | int ret = -ENOTTY; |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 183 | int time; |
| 184 | |
| 185 | switch (cmd) { |
| 186 | case WDIOC_GETSUPPORT: |
| 187 | ret = copy_to_user((struct watchdog_info *)arg, &ident, |
| 188 | sizeof(ident)) ? -EFAULT : 0; |
| 189 | break; |
| 190 | |
| 191 | case WDIOC_GETSTATUS: |
| 192 | ret = put_user(0, (int *)arg); |
| 193 | break; |
| 194 | |
| 195 | case WDIOC_GETBOOTSTATUS: |
| 196 | ret = put_user(boot_status, (int *)arg); |
| 197 | break; |
| 198 | |
Wim Van Sebroeck | 0c06090 | 2008-07-18 11:41:17 +0000 | [diff] [blame] | 199 | case WDIOC_KEEPALIVE: |
| 200 | wdt_enable(); |
| 201 | ret = 0; |
| 202 | break; |
| 203 | |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 204 | case WDIOC_SETTIMEOUT: |
| 205 | ret = get_user(time, (int *)arg); |
| 206 | if (ret) |
| 207 | break; |
| 208 | |
| 209 | if (time <= 0 || time > MAX_HEARTBEAT) { |
| 210 | ret = -EINVAL; |
| 211 | break; |
| 212 | } |
| 213 | |
| 214 | heartbeat = time; |
| 215 | wdt_enable(); |
| 216 | /* Fall through */ |
| 217 | |
| 218 | case WDIOC_GETTIMEOUT: |
| 219 | ret = put_user(heartbeat, (int *)arg); |
| 220 | break; |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 221 | } |
| 222 | return ret; |
| 223 | } |
| 224 | |
| 225 | static int pnx4008_wdt_release(struct inode *inode, struct file *file) |
| 226 | { |
| 227 | if (!test_bit(WDT_OK_TO_CLOSE, &wdt_status)) |
| 228 | printk(KERN_WARNING "WATCHDOG: Device closed unexpectdly\n"); |
| 229 | |
| 230 | wdt_disable(); |
Russell King | 24fd1ed | 2009-11-20 13:04:14 +0000 | [diff] [blame] | 231 | clk_disable(wdt_clk); |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 232 | clear_bit(WDT_IN_USE, &wdt_status); |
| 233 | clear_bit(WDT_OK_TO_CLOSE, &wdt_status); |
| 234 | |
| 235 | return 0; |
| 236 | } |
| 237 | |
Arjan van de Ven | 2b8693c | 2007-02-12 00:55:32 -0800 | [diff] [blame] | 238 | static const struct file_operations pnx4008_wdt_fops = { |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 239 | .owner = THIS_MODULE, |
| 240 | .llseek = no_llseek, |
| 241 | .write = pnx4008_wdt_write, |
Alan Cox | 84ca995 | 2008-05-19 14:07:48 +0100 | [diff] [blame] | 242 | .unlocked_ioctl = pnx4008_wdt_ioctl, |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 243 | .open = pnx4008_wdt_open, |
| 244 | .release = pnx4008_wdt_release, |
| 245 | }; |
| 246 | |
| 247 | static struct miscdevice pnx4008_wdt_miscdev = { |
| 248 | .minor = WATCHDOG_MINOR, |
| 249 | .name = "watchdog", |
| 250 | .fops = &pnx4008_wdt_fops, |
| 251 | }; |
| 252 | |
Wim Van Sebroeck | b6bf291 | 2009-04-14 20:30:55 +0000 | [diff] [blame] | 253 | static int __devinit pnx4008_wdt_probe(struct platform_device *pdev) |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 254 | { |
| 255 | int ret = 0, size; |
| 256 | struct resource *res; |
| 257 | |
| 258 | if (heartbeat < 1 || heartbeat > MAX_HEARTBEAT) |
| 259 | heartbeat = DEFAULT_HEARTBEAT; |
| 260 | |
| 261 | printk(KERN_INFO MODULE_NAME |
| 262 | "PNX4008 Watchdog Timer: heartbeat %d sec\n", heartbeat); |
| 263 | |
| 264 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 265 | if (res == NULL) { |
| 266 | printk(KERN_INFO MODULE_NAME |
| 267 | "failed to get memory region resouce\n"); |
| 268 | return -ENOENT; |
| 269 | } |
| 270 | |
H Hartley Sweeten | b782a56 | 2009-12-04 12:24:04 -0500 | [diff] [blame] | 271 | size = resource_size(res); |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 272 | wdt_mem = request_mem_region(res->start, size, pdev->name); |
| 273 | |
| 274 | if (wdt_mem == NULL) { |
| 275 | printk(KERN_INFO MODULE_NAME "failed to get memory region\n"); |
| 276 | return -ENOENT; |
| 277 | } |
| 278 | wdt_base = (void __iomem *)IO_ADDRESS(res->start); |
| 279 | |
Russell King | 9bb787f | 2009-11-20 13:07:28 +0000 | [diff] [blame] | 280 | wdt_clk = clk_get(&pdev->dev, NULL); |
Akinobu Mita | 9cd4461 | 2006-12-19 17:51:44 +0900 | [diff] [blame] | 281 | if (IS_ERR(wdt_clk)) { |
| 282 | ret = PTR_ERR(wdt_clk); |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 283 | release_resource(wdt_mem); |
| 284 | kfree(wdt_mem); |
| 285 | goto out; |
Russell King | 24fd1ed | 2009-11-20 13:04:14 +0000 | [diff] [blame] | 286 | } |
| 287 | |
| 288 | ret = clk_enable(wdt_clk); |
| 289 | if (ret) { |
| 290 | release_resource(wdt_mem); |
| 291 | kfree(wdt_mem); |
| 292 | goto out; |
| 293 | } |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 294 | |
| 295 | ret = misc_register(&pnx4008_wdt_miscdev); |
| 296 | if (ret < 0) { |
| 297 | printk(KERN_ERR MODULE_NAME "cannot register misc device\n"); |
| 298 | release_resource(wdt_mem); |
| 299 | kfree(wdt_mem); |
Russell King | 24fd1ed | 2009-11-20 13:04:14 +0000 | [diff] [blame] | 300 | clk_disable(wdt_clk); |
| 301 | clk_put(wdt_clk); |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 302 | } else { |
| 303 | boot_status = (__raw_readl(WDTIM_RES(wdt_base)) & WDOG_RESET) ? |
| 304 | WDIOF_CARDRESET : 0; |
| 305 | wdt_disable(); /*disable for now */ |
Russell King | 24fd1ed | 2009-11-20 13:04:14 +0000 | [diff] [blame] | 306 | clk_disable(wdt_clk); |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 307 | set_bit(WDT_DEVICE_INITED, &wdt_status); |
| 308 | } |
| 309 | |
| 310 | out: |
| 311 | return ret; |
| 312 | } |
| 313 | |
Wim Van Sebroeck | b6bf291 | 2009-04-14 20:30:55 +0000 | [diff] [blame] | 314 | static int __devexit pnx4008_wdt_remove(struct platform_device *pdev) |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 315 | { |
Wim Van Sebroeck | f676449 | 2006-07-30 20:06:07 +0200 | [diff] [blame] | 316 | misc_deregister(&pnx4008_wdt_miscdev); |
Russell King | 24fd1ed | 2009-11-20 13:04:14 +0000 | [diff] [blame] | 317 | |
| 318 | clk_disable(wdt_clk); |
| 319 | clk_put(wdt_clk); |
| 320 | |
Wim Van Sebroeck | f676449 | 2006-07-30 20:06:07 +0200 | [diff] [blame] | 321 | if (wdt_mem) { |
| 322 | release_resource(wdt_mem); |
| 323 | kfree(wdt_mem); |
| 324 | wdt_mem = NULL; |
| 325 | } |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 326 | return 0; |
| 327 | } |
| 328 | |
| 329 | static struct platform_driver platform_wdt_driver = { |
| 330 | .driver = { |
Russell King | 1508c99 | 2009-11-20 13:07:57 +0000 | [diff] [blame] | 331 | .name = "pnx4008-watchdog", |
Kay Sievers | f37d193 | 2008-04-10 21:29:23 -0700 | [diff] [blame] | 332 | .owner = THIS_MODULE, |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 333 | }, |
| 334 | .probe = pnx4008_wdt_probe, |
Wim Van Sebroeck | b6bf291 | 2009-04-14 20:30:55 +0000 | [diff] [blame] | 335 | .remove = __devexit_p(pnx4008_wdt_remove), |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 336 | }; |
| 337 | |
| 338 | static int __init pnx4008_wdt_init(void) |
| 339 | { |
| 340 | return platform_driver_register(&platform_wdt_driver); |
| 341 | } |
| 342 | |
| 343 | static void __exit pnx4008_wdt_exit(void) |
| 344 | { |
Florian Fainelli | bb0a38d | 2007-10-17 15:42:22 +0200 | [diff] [blame] | 345 | platform_driver_unregister(&platform_wdt_driver); |
Vitaly Wool | 9325fa3 | 2006-06-26 19:31:49 +0400 | [diff] [blame] | 346 | } |
| 347 | |
| 348 | module_init(pnx4008_wdt_init); |
| 349 | module_exit(pnx4008_wdt_exit); |
| 350 | |
| 351 | MODULE_AUTHOR("MontaVista Software, Inc. <source@mvista.com>"); |
| 352 | MODULE_DESCRIPTION("PNX4008 Watchdog Driver"); |
| 353 | |
| 354 | module_param(heartbeat, int, 0); |
| 355 | MODULE_PARM_DESC(heartbeat, |
| 356 | "Watchdog heartbeat period in seconds from 1 to " |
| 357 | __MODULE_STRING(MAX_HEARTBEAT) ", default " |
| 358 | __MODULE_STRING(DEFAULT_HEARTBEAT)); |
| 359 | |
| 360 | module_param(nowayout, int, 0); |
| 361 | MODULE_PARM_DESC(nowayout, |
| 362 | "Set to 1 to keep watchdog running after device release"); |
| 363 | |
| 364 | MODULE_LICENSE("GPL"); |
| 365 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |
Russell King | 1508c99 | 2009-11-20 13:07:57 +0000 | [diff] [blame] | 366 | MODULE_ALIAS("platform:pnx4008-watchdog"); |