1b7e04f8cSWim Van Sebroeck /* 2b7e04f8cSWim Van Sebroeck * NS pc87413-wdt Watchdog Timer driver for Linux 2.6.x.x 3b7e04f8cSWim Van Sebroeck * 4b7e04f8cSWim Van Sebroeck * This code is based on wdt.c with original copyright. 5b7e04f8cSWim Van Sebroeck * 6b7e04f8cSWim Van Sebroeck * (C) Copyright 2006 Sven Anders, <anders@anduras.de> 7b7e04f8cSWim Van Sebroeck * and Marcus Junker, <junker@anduras.de> 8b7e04f8cSWim Van Sebroeck * 9b7e04f8cSWim Van Sebroeck * This program is free software; you can redistribute it and/or 10b7e04f8cSWim Van Sebroeck * modify it under the terms of the GNU General Public License 11b7e04f8cSWim Van Sebroeck * as published by the Free Software Foundation; either version 12b7e04f8cSWim Van Sebroeck * 2 of the License, or (at your option) any later version. 13b7e04f8cSWim Van Sebroeck * 14b7e04f8cSWim Van Sebroeck * Neither Sven Anders, Marcus Junker nor ANDURAS AG 15b7e04f8cSWim Van Sebroeck * admit liability nor provide warranty for any of this software. 16b7e04f8cSWim Van Sebroeck * This material is provided "AS-IS" and at no charge. 17b7e04f8cSWim Van Sebroeck * 18b7e04f8cSWim Van Sebroeck * Release 1.1 19b7e04f8cSWim Van Sebroeck */ 20b7e04f8cSWim Van Sebroeck 2127c766aaSJoe Perches #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 2227c766aaSJoe Perches 23b7e04f8cSWim Van Sebroeck #include <linux/module.h> 24b7e04f8cSWim Van Sebroeck #include <linux/types.h> 25b7e04f8cSWim Van Sebroeck #include <linux/miscdevice.h> 26b7e04f8cSWim Van Sebroeck #include <linux/watchdog.h> 27b7e04f8cSWim Van Sebroeck #include <linux/ioport.h> 28b7e04f8cSWim Van Sebroeck #include <linux/delay.h> 29b7e04f8cSWim Van Sebroeck #include <linux/notifier.h> 30b7e04f8cSWim Van Sebroeck #include <linux/fs.h> 31b7e04f8cSWim Van Sebroeck #include <linux/reboot.h> 32b7e04f8cSWim Van Sebroeck #include <linux/init.h> 33b7e04f8cSWim Van Sebroeck #include <linux/spinlock.h> 34b7e04f8cSWim Van Sebroeck #include <linux/moduleparam.h> 35aee334c2SAlan Cox #include <linux/io.h> 36aee334c2SAlan Cox #include <linux/uaccess.h> 37b7e04f8cSWim Van Sebroeck 38b7e04f8cSWim Van Sebroeck #include <asm/system.h> 39b7e04f8cSWim Van Sebroeck 40b7e04f8cSWim Van Sebroeck /* #define DEBUG 1 */ 41b7e04f8cSWim Van Sebroeck 42b7e04f8cSWim Van Sebroeck #define DEFAULT_TIMEOUT 1 /* 1 minute */ 43b7e04f8cSWim Van Sebroeck #define MAX_TIMEOUT 255 44b7e04f8cSWim Van Sebroeck 45b7e04f8cSWim Van Sebroeck #define VERSION "1.1" 46b7e04f8cSWim Van Sebroeck #define MODNAME "pc87413 WDT" 47b7e04f8cSWim Van Sebroeck #define DPFX MODNAME " - DEBUG: " 48b7e04f8cSWim Van Sebroeck 49b7e04f8cSWim Van Sebroeck #define WDT_INDEX_IO_PORT (io+0) /* I/O port base (index register) */ 50b7e04f8cSWim Van Sebroeck #define WDT_DATA_IO_PORT (WDT_INDEX_IO_PORT+1) 51b7e04f8cSWim Van Sebroeck #define SWC_LDN 0x04 52b7e04f8cSWim Van Sebroeck #define SIOCFG2 0x22 /* Serial IO register */ 5325985edcSLucas De Marchi #define WDCTL 0x10 /* Watchdog-Timer-Control-Register */ 54b7e04f8cSWim Van Sebroeck #define WDTO 0x11 /* Watchdog timeout register */ 55b7e04f8cSWim Van Sebroeck #define WDCFG 0x12 /* Watchdog config register */ 56b7e04f8cSWim Van Sebroeck 5776550d32SRandy Dunlap #define IO_DEFAULT 0x2E /* Address used on Portwell Boards */ 5876550d32SRandy Dunlap 5976550d32SRandy Dunlap static int io = IO_DEFAULT; 607ccdb946SJonathan McDowell static int swc_base_addr = -1; 61b7e04f8cSWim Van Sebroeck 62b7e04f8cSWim Van Sebroeck static int timeout = DEFAULT_TIMEOUT; /* timeout value */ 63aee334c2SAlan Cox static unsigned long timer_enabled; /* is the timer enabled? */ 64b7e04f8cSWim Van Sebroeck 65b7e04f8cSWim Van Sebroeck static char expect_close; /* is the close expected? */ 66b7e04f8cSWim Van Sebroeck 67aee334c2SAlan Cox static DEFINE_SPINLOCK(io_lock); /* to guard us from io races */ 68b7e04f8cSWim Van Sebroeck 6986a1e189SWim Van Sebroeck static bool nowayout = WATCHDOG_NOWAYOUT; 70b7e04f8cSWim Van Sebroeck 71b7e04f8cSWim Van Sebroeck /* -- Low level function ----------------------------------------*/ 72b7e04f8cSWim Van Sebroeck 73b7e04f8cSWim Van Sebroeck /* Select pins for Watchdog output */ 74b7e04f8cSWim Van Sebroeck 75b7e04f8cSWim Van Sebroeck static inline void pc87413_select_wdt_out(void) 76b7e04f8cSWim Van Sebroeck { 77b7e04f8cSWim Van Sebroeck unsigned int cr_data = 0; 78b7e04f8cSWim Van Sebroeck 79b7e04f8cSWim Van Sebroeck /* Step 1: Select multiple pin,pin55,as WDT output */ 80b7e04f8cSWim Van Sebroeck 81b7e04f8cSWim Van Sebroeck outb_p(SIOCFG2, WDT_INDEX_IO_PORT); 82b7e04f8cSWim Van Sebroeck 83b7e04f8cSWim Van Sebroeck cr_data = inb(WDT_DATA_IO_PORT); 84b7e04f8cSWim Van Sebroeck 85b7e04f8cSWim Van Sebroeck cr_data |= 0x80; /* Set Bit7 to 1*/ 86b7e04f8cSWim Van Sebroeck outb_p(SIOCFG2, WDT_INDEX_IO_PORT); 87b7e04f8cSWim Van Sebroeck 88b7e04f8cSWim Van Sebroeck outb_p(cr_data, WDT_DATA_IO_PORT); 89b7e04f8cSWim Van Sebroeck 90b7e04f8cSWim Van Sebroeck #ifdef DEBUG 9127c766aaSJoe Perches pr_info(DPFX 92aee334c2SAlan Cox "Select multiple pin,pin55,as WDT output: Bit7 to 1: %d\n", 93aee334c2SAlan Cox cr_data); 94b7e04f8cSWim Van Sebroeck #endif 95b7e04f8cSWim Van Sebroeck } 96b7e04f8cSWim Van Sebroeck 97b7e04f8cSWim Van Sebroeck /* Enable SWC functions */ 98b7e04f8cSWim Van Sebroeck 99b7e04f8cSWim Van Sebroeck static inline void pc87413_enable_swc(void) 100b7e04f8cSWim Van Sebroeck { 101b7e04f8cSWim Van Sebroeck unsigned int cr_data = 0; 102b7e04f8cSWim Van Sebroeck 103b7e04f8cSWim Van Sebroeck /* Step 2: Enable SWC functions */ 104b7e04f8cSWim Van Sebroeck 105b7e04f8cSWim Van Sebroeck outb_p(0x07, WDT_INDEX_IO_PORT); /* Point SWC_LDN (LDN=4) */ 106b7e04f8cSWim Van Sebroeck outb_p(SWC_LDN, WDT_DATA_IO_PORT); 107b7e04f8cSWim Van Sebroeck 108b7e04f8cSWim Van Sebroeck outb_p(0x30, WDT_INDEX_IO_PORT); /* Read Index 0x30 First */ 109b7e04f8cSWim Van Sebroeck cr_data = inb(WDT_DATA_IO_PORT); 110b7e04f8cSWim Van Sebroeck cr_data |= 0x01; /* Set Bit0 to 1 */ 111b7e04f8cSWim Van Sebroeck outb_p(0x30, WDT_INDEX_IO_PORT); 112b7e04f8cSWim Van Sebroeck outb_p(cr_data, WDT_DATA_IO_PORT); /* Index0x30_bit0P1 */ 113b7e04f8cSWim Van Sebroeck 114b7e04f8cSWim Van Sebroeck #ifdef DEBUG 11527c766aaSJoe Perches pr_info(DPFX "pc87413 - Enable SWC functions\n"); 116b7e04f8cSWim Van Sebroeck #endif 117b7e04f8cSWim Van Sebroeck } 118b7e04f8cSWim Van Sebroeck 119b7e04f8cSWim Van Sebroeck /* Read SWC I/O base address */ 120b7e04f8cSWim Van Sebroeck 1217ccdb946SJonathan McDowell static void pc87413_get_swc_base_addr(void) 122b7e04f8cSWim Van Sebroeck { 123b7e04f8cSWim Van Sebroeck unsigned char addr_l, addr_h = 0; 124b7e04f8cSWim Van Sebroeck 125b7e04f8cSWim Van Sebroeck /* Step 3: Read SWC I/O Base Address */ 126b7e04f8cSWim Van Sebroeck 127b7e04f8cSWim Van Sebroeck outb_p(0x60, WDT_INDEX_IO_PORT); /* Read Index 0x60 */ 128b7e04f8cSWim Van Sebroeck addr_h = inb(WDT_DATA_IO_PORT); 129b7e04f8cSWim Van Sebroeck 130b7e04f8cSWim Van Sebroeck outb_p(0x61, WDT_INDEX_IO_PORT); /* Read Index 0x61 */ 131b7e04f8cSWim Van Sebroeck 132b7e04f8cSWim Van Sebroeck addr_l = inb(WDT_DATA_IO_PORT); 133b7e04f8cSWim Van Sebroeck 134b7e04f8cSWim Van Sebroeck swc_base_addr = (addr_h << 8) + addr_l; 135b7e04f8cSWim Van Sebroeck #ifdef DEBUG 13627c766aaSJoe Perches pr_info(DPFX 137aee334c2SAlan Cox "Read SWC I/O Base Address: low %d, high %d, res %d\n", 138aee334c2SAlan Cox addr_l, addr_h, swc_base_addr); 139b7e04f8cSWim Van Sebroeck #endif 140b7e04f8cSWim Van Sebroeck } 141b7e04f8cSWim Van Sebroeck 142b7e04f8cSWim Van Sebroeck /* Select Bank 3 of SWC */ 143b7e04f8cSWim Van Sebroeck 1447ccdb946SJonathan McDowell static inline void pc87413_swc_bank3(void) 145b7e04f8cSWim Van Sebroeck { 146b7e04f8cSWim Van Sebroeck /* Step 4: Select Bank3 of SWC */ 147b7e04f8cSWim Van Sebroeck outb_p(inb(swc_base_addr + 0x0f) | 0x03, swc_base_addr + 0x0f); 148b7e04f8cSWim Van Sebroeck #ifdef DEBUG 14927c766aaSJoe Perches pr_info(DPFX "Select Bank3 of SWC\n"); 150b7e04f8cSWim Van Sebroeck #endif 151b7e04f8cSWim Van Sebroeck } 152b7e04f8cSWim Van Sebroeck 153b7e04f8cSWim Van Sebroeck /* Set watchdog timeout to x minutes */ 154b7e04f8cSWim Van Sebroeck 1557ccdb946SJonathan McDowell static inline void pc87413_programm_wdto(char pc87413_time) 156b7e04f8cSWim Van Sebroeck { 157b7e04f8cSWim Van Sebroeck /* Step 5: Programm WDTO, Twd. */ 158b7e04f8cSWim Van Sebroeck outb_p(pc87413_time, swc_base_addr + WDTO); 159b7e04f8cSWim Van Sebroeck #ifdef DEBUG 16027c766aaSJoe Perches pr_info(DPFX "Set WDTO to %d minutes\n", pc87413_time); 161b7e04f8cSWim Van Sebroeck #endif 162b7e04f8cSWim Van Sebroeck } 163b7e04f8cSWim Van Sebroeck 164b7e04f8cSWim Van Sebroeck /* Enable WDEN */ 165b7e04f8cSWim Van Sebroeck 1667ccdb946SJonathan McDowell static inline void pc87413_enable_wden(void) 167b7e04f8cSWim Van Sebroeck { 168b7e04f8cSWim Van Sebroeck /* Step 6: Enable WDEN */ 169b7e04f8cSWim Van Sebroeck outb_p(inb(swc_base_addr + WDCTL) | 0x01, swc_base_addr + WDCTL); 170b7e04f8cSWim Van Sebroeck #ifdef DEBUG 17127c766aaSJoe Perches pr_info(DPFX "Enable WDEN\n"); 172b7e04f8cSWim Van Sebroeck #endif 173b7e04f8cSWim Van Sebroeck } 174b7e04f8cSWim Van Sebroeck 175b7e04f8cSWim Van Sebroeck /* Enable SW_WD_TREN */ 1767ccdb946SJonathan McDowell static inline void pc87413_enable_sw_wd_tren(void) 177b7e04f8cSWim Van Sebroeck { 178b7e04f8cSWim Van Sebroeck /* Enable SW_WD_TREN */ 179b7e04f8cSWim Van Sebroeck outb_p(inb(swc_base_addr + WDCFG) | 0x80, swc_base_addr + WDCFG); 180b7e04f8cSWim Van Sebroeck #ifdef DEBUG 18127c766aaSJoe Perches pr_info(DPFX "Enable SW_WD_TREN\n"); 182b7e04f8cSWim Van Sebroeck #endif 183b7e04f8cSWim Van Sebroeck } 184b7e04f8cSWim Van Sebroeck 185b7e04f8cSWim Van Sebroeck /* Disable SW_WD_TREN */ 186b7e04f8cSWim Van Sebroeck 1877ccdb946SJonathan McDowell static inline void pc87413_disable_sw_wd_tren(void) 188b7e04f8cSWim Van Sebroeck { 189b7e04f8cSWim Van Sebroeck /* Disable SW_WD_TREN */ 190b7e04f8cSWim Van Sebroeck outb_p(inb(swc_base_addr + WDCFG) & 0x7f, swc_base_addr + WDCFG); 191b7e04f8cSWim Van Sebroeck #ifdef DEBUG 19227c766aaSJoe Perches pr_info(DPFX "pc87413 - Disable SW_WD_TREN\n"); 193b7e04f8cSWim Van Sebroeck #endif 194b7e04f8cSWim Van Sebroeck } 195b7e04f8cSWim Van Sebroeck 196b7e04f8cSWim Van Sebroeck /* Enable SW_WD_TRG */ 197b7e04f8cSWim Van Sebroeck 1987ccdb946SJonathan McDowell static inline void pc87413_enable_sw_wd_trg(void) 199b7e04f8cSWim Van Sebroeck { 200b7e04f8cSWim Van Sebroeck /* Enable SW_WD_TRG */ 201b7e04f8cSWim Van Sebroeck outb_p(inb(swc_base_addr + WDCTL) | 0x80, swc_base_addr + WDCTL); 202b7e04f8cSWim Van Sebroeck #ifdef DEBUG 20327c766aaSJoe Perches pr_info(DPFX "pc87413 - Enable SW_WD_TRG\n"); 204b7e04f8cSWim Van Sebroeck #endif 205b7e04f8cSWim Van Sebroeck } 206b7e04f8cSWim Van Sebroeck 207b7e04f8cSWim Van Sebroeck /* Disable SW_WD_TRG */ 208b7e04f8cSWim Van Sebroeck 2097ccdb946SJonathan McDowell static inline void pc87413_disable_sw_wd_trg(void) 210b7e04f8cSWim Van Sebroeck { 211b7e04f8cSWim Van Sebroeck /* Disable SW_WD_TRG */ 212b7e04f8cSWim Van Sebroeck outb_p(inb(swc_base_addr + WDCTL) & 0x7f, swc_base_addr + WDCTL); 213b7e04f8cSWim Van Sebroeck #ifdef DEBUG 21427c766aaSJoe Perches pr_info(DPFX "Disable SW_WD_TRG\n"); 215b7e04f8cSWim Van Sebroeck #endif 216b7e04f8cSWim Van Sebroeck } 217b7e04f8cSWim Van Sebroeck 218b7e04f8cSWim Van Sebroeck /* -- Higher level functions ------------------------------------*/ 219b7e04f8cSWim Van Sebroeck 220b7e04f8cSWim Van Sebroeck /* Enable the watchdog */ 221b7e04f8cSWim Van Sebroeck 222b7e04f8cSWim Van Sebroeck static void pc87413_enable(void) 223b7e04f8cSWim Van Sebroeck { 224b7e04f8cSWim Van Sebroeck spin_lock(&io_lock); 225b7e04f8cSWim Van Sebroeck 2267ccdb946SJonathan McDowell pc87413_swc_bank3(); 2277ccdb946SJonathan McDowell pc87413_programm_wdto(timeout); 2287ccdb946SJonathan McDowell pc87413_enable_wden(); 2297ccdb946SJonathan McDowell pc87413_enable_sw_wd_tren(); 2307ccdb946SJonathan McDowell pc87413_enable_sw_wd_trg(); 231b7e04f8cSWim Van Sebroeck 232b7e04f8cSWim Van Sebroeck spin_unlock(&io_lock); 233b7e04f8cSWim Van Sebroeck } 234b7e04f8cSWim Van Sebroeck 235b7e04f8cSWim Van Sebroeck /* Disable the watchdog */ 236b7e04f8cSWim Van Sebroeck 237b7e04f8cSWim Van Sebroeck static void pc87413_disable(void) 238b7e04f8cSWim Van Sebroeck { 239b7e04f8cSWim Van Sebroeck spin_lock(&io_lock); 240b7e04f8cSWim Van Sebroeck 2417ccdb946SJonathan McDowell pc87413_swc_bank3(); 2427ccdb946SJonathan McDowell pc87413_disable_sw_wd_tren(); 2437ccdb946SJonathan McDowell pc87413_disable_sw_wd_trg(); 2447ccdb946SJonathan McDowell pc87413_programm_wdto(0); 245b7e04f8cSWim Van Sebroeck 246b7e04f8cSWim Van Sebroeck spin_unlock(&io_lock); 247b7e04f8cSWim Van Sebroeck } 248b7e04f8cSWim Van Sebroeck 249b7e04f8cSWim Van Sebroeck /* Refresh the watchdog */ 250b7e04f8cSWim Van Sebroeck 251b7e04f8cSWim Van Sebroeck static void pc87413_refresh(void) 252b7e04f8cSWim Van Sebroeck { 253b7e04f8cSWim Van Sebroeck spin_lock(&io_lock); 254b7e04f8cSWim Van Sebroeck 2557ccdb946SJonathan McDowell pc87413_swc_bank3(); 2567ccdb946SJonathan McDowell pc87413_disable_sw_wd_tren(); 2577ccdb946SJonathan McDowell pc87413_disable_sw_wd_trg(); 2587ccdb946SJonathan McDowell pc87413_programm_wdto(timeout); 2597ccdb946SJonathan McDowell pc87413_enable_wden(); 2607ccdb946SJonathan McDowell pc87413_enable_sw_wd_tren(); 2617ccdb946SJonathan McDowell pc87413_enable_sw_wd_trg(); 262b7e04f8cSWim Van Sebroeck 263b7e04f8cSWim Van Sebroeck spin_unlock(&io_lock); 264b7e04f8cSWim Van Sebroeck } 265b7e04f8cSWim Van Sebroeck 266b7e04f8cSWim Van Sebroeck /* -- File operations -------------------------------------------*/ 267b7e04f8cSWim Van Sebroeck 268b7e04f8cSWim Van Sebroeck /** 269b7e04f8cSWim Van Sebroeck * pc87413_open: 270b7e04f8cSWim Van Sebroeck * @inode: inode of device 271b7e04f8cSWim Van Sebroeck * @file: file handle to device 272b7e04f8cSWim Van Sebroeck * 273b7e04f8cSWim Van Sebroeck */ 274b7e04f8cSWim Van Sebroeck 275b7e04f8cSWim Van Sebroeck static int pc87413_open(struct inode *inode, struct file *file) 276b7e04f8cSWim Van Sebroeck { 277b7e04f8cSWim Van Sebroeck /* /dev/watchdog can only be opened once */ 278b7e04f8cSWim Van Sebroeck 279b7e04f8cSWim Van Sebroeck if (test_and_set_bit(0, &timer_enabled)) 280b7e04f8cSWim Van Sebroeck return -EBUSY; 281b7e04f8cSWim Van Sebroeck 282b7e04f8cSWim Van Sebroeck if (nowayout) 283b7e04f8cSWim Van Sebroeck __module_get(THIS_MODULE); 284b7e04f8cSWim Van Sebroeck 285b7e04f8cSWim Van Sebroeck /* Reload and activate timer */ 286b7e04f8cSWim Van Sebroeck pc87413_refresh(); 287b7e04f8cSWim Van Sebroeck 28827c766aaSJoe Perches pr_info("Watchdog enabled. Timeout set to %d minute(s).\n", timeout); 289b7e04f8cSWim Van Sebroeck 290b7e04f8cSWim Van Sebroeck return nonseekable_open(inode, file); 291b7e04f8cSWim Van Sebroeck } 292b7e04f8cSWim Van Sebroeck 293b7e04f8cSWim Van Sebroeck /** 294b7e04f8cSWim Van Sebroeck * pc87413_release: 295b7e04f8cSWim Van Sebroeck * @inode: inode to board 296b7e04f8cSWim Van Sebroeck * @file: file handle to board 297b7e04f8cSWim Van Sebroeck * 298b7e04f8cSWim Van Sebroeck * The watchdog has a configurable API. There is a religious dispute 299b7e04f8cSWim Van Sebroeck * between people who want their watchdog to be able to shut down and 300b7e04f8cSWim Van Sebroeck * those who want to be sure if the watchdog manager dies the machine 301b7e04f8cSWim Van Sebroeck * reboots. In the former case we disable the counters, in the latter 302b7e04f8cSWim Van Sebroeck * case you have to open it again very soon. 303b7e04f8cSWim Van Sebroeck */ 304b7e04f8cSWim Van Sebroeck 305b7e04f8cSWim Van Sebroeck static int pc87413_release(struct inode *inode, struct file *file) 306b7e04f8cSWim Van Sebroeck { 307b7e04f8cSWim Van Sebroeck /* Shut off the timer. */ 308b7e04f8cSWim Van Sebroeck 309b7e04f8cSWim Van Sebroeck if (expect_close == 42) { 310b7e04f8cSWim Van Sebroeck pc87413_disable(); 31127c766aaSJoe Perches pr_info("Watchdog disabled, sleeping again...\n"); 312b7e04f8cSWim Van Sebroeck } else { 31327c766aaSJoe Perches pr_crit("Unexpected close, not stopping watchdog!\n"); 314b7e04f8cSWim Van Sebroeck pc87413_refresh(); 315b7e04f8cSWim Van Sebroeck } 316b7e04f8cSWim Van Sebroeck clear_bit(0, &timer_enabled); 317b7e04f8cSWim Van Sebroeck expect_close = 0; 318b7e04f8cSWim Van Sebroeck return 0; 319b7e04f8cSWim Van Sebroeck } 320b7e04f8cSWim Van Sebroeck 321b7e04f8cSWim Van Sebroeck /** 322b7e04f8cSWim Van Sebroeck * pc87413_status: 323b7e04f8cSWim Van Sebroeck * 324b7e04f8cSWim Van Sebroeck * return, if the watchdog is enabled (timeout is set...) 325b7e04f8cSWim Van Sebroeck */ 326b7e04f8cSWim Van Sebroeck 327b7e04f8cSWim Van Sebroeck 328b7e04f8cSWim Van Sebroeck static int pc87413_status(void) 329b7e04f8cSWim Van Sebroeck { 330b7e04f8cSWim Van Sebroeck return 0; /* currently not supported */ 331b7e04f8cSWim Van Sebroeck } 332b7e04f8cSWim Van Sebroeck 333b7e04f8cSWim Van Sebroeck /** 334b7e04f8cSWim Van Sebroeck * pc87413_write: 335b7e04f8cSWim Van Sebroeck * @file: file handle to the watchdog 336b7e04f8cSWim Van Sebroeck * @data: data buffer to write 337b7e04f8cSWim Van Sebroeck * @len: length in bytes 338b7e04f8cSWim Van Sebroeck * @ppos: pointer to the position to write. No seeks allowed 339b7e04f8cSWim Van Sebroeck * 340b7e04f8cSWim Van Sebroeck * A write to a watchdog device is defined as a keepalive signal. Any 341b7e04f8cSWim Van Sebroeck * write of data will do, as we we don't define content meaning. 342b7e04f8cSWim Van Sebroeck */ 343b7e04f8cSWim Van Sebroeck 344b7e04f8cSWim Van Sebroeck static ssize_t pc87413_write(struct file *file, const char __user *data, 345b7e04f8cSWim Van Sebroeck size_t len, loff_t *ppos) 346b7e04f8cSWim Van Sebroeck { 347b7e04f8cSWim Van Sebroeck /* See if we got the magic character 'V' and reload the timer */ 348b7e04f8cSWim Van Sebroeck if (len) { 349b7e04f8cSWim Van Sebroeck if (!nowayout) { 350b7e04f8cSWim Van Sebroeck size_t i; 351b7e04f8cSWim Van Sebroeck 352b7e04f8cSWim Van Sebroeck /* reset expect flag */ 353b7e04f8cSWim Van Sebroeck expect_close = 0; 354b7e04f8cSWim Van Sebroeck 355aee334c2SAlan Cox /* scan to see whether or not we got the 356aee334c2SAlan Cox magic character */ 357b7e04f8cSWim Van Sebroeck for (i = 0; i != len; i++) { 358b7e04f8cSWim Van Sebroeck char c; 359b7e04f8cSWim Van Sebroeck if (get_user(c, data + i)) 360b7e04f8cSWim Van Sebroeck return -EFAULT; 361b7e04f8cSWim Van Sebroeck if (c == 'V') 362b7e04f8cSWim Van Sebroeck expect_close = 42; 363b7e04f8cSWim Van Sebroeck } 364b7e04f8cSWim Van Sebroeck } 365b7e04f8cSWim Van Sebroeck 366b7e04f8cSWim Van Sebroeck /* someone wrote to us, we should reload the timer */ 367b7e04f8cSWim Van Sebroeck pc87413_refresh(); 368b7e04f8cSWim Van Sebroeck } 369b7e04f8cSWim Van Sebroeck return len; 370b7e04f8cSWim Van Sebroeck } 371b7e04f8cSWim Van Sebroeck 372b7e04f8cSWim Van Sebroeck /** 373b7e04f8cSWim Van Sebroeck * pc87413_ioctl: 374b7e04f8cSWim Van Sebroeck * @file: file handle to the device 375b7e04f8cSWim Van Sebroeck * @cmd: watchdog command 376b7e04f8cSWim Van Sebroeck * @arg: argument pointer 377b7e04f8cSWim Van Sebroeck * 378b7e04f8cSWim Van Sebroeck * The watchdog API defines a common set of functions for all watchdogs 379b7e04f8cSWim Van Sebroeck * according to their available features. We only actually usefully support 380b7e04f8cSWim Van Sebroeck * querying capabilities and current status. 381b7e04f8cSWim Van Sebroeck */ 382b7e04f8cSWim Van Sebroeck 383aee334c2SAlan Cox static long pc87413_ioctl(struct file *file, unsigned int cmd, 384aee334c2SAlan Cox unsigned long arg) 385b7e04f8cSWim Van Sebroeck { 386b7e04f8cSWim Van Sebroeck int new_timeout; 387b7e04f8cSWim Van Sebroeck 388b7e04f8cSWim Van Sebroeck union { 389b7e04f8cSWim Van Sebroeck struct watchdog_info __user *ident; 390b7e04f8cSWim Van Sebroeck int __user *i; 391b7e04f8cSWim Van Sebroeck } uarg; 392b7e04f8cSWim Van Sebroeck 39342747d71SWim Van Sebroeck static const struct watchdog_info ident = { 394b7e04f8cSWim Van Sebroeck .options = WDIOF_KEEPALIVEPING | 395b7e04f8cSWim Van Sebroeck WDIOF_SETTIMEOUT | 396b7e04f8cSWim Van Sebroeck WDIOF_MAGICCLOSE, 397b7e04f8cSWim Van Sebroeck .firmware_version = 1, 3987944d3a5SWim Van Sebroeck .identity = "PC87413(HF/F) watchdog", 399b7e04f8cSWim Van Sebroeck }; 400b7e04f8cSWim Van Sebroeck 401b7e04f8cSWim Van Sebroeck uarg.i = (int __user *)arg; 402b7e04f8cSWim Van Sebroeck 403b7e04f8cSWim Van Sebroeck switch (cmd) { 404b7e04f8cSWim Van Sebroeck case WDIOC_GETSUPPORT: 405b7e04f8cSWim Van Sebroeck return copy_to_user(uarg.ident, &ident, 406b7e04f8cSWim Van Sebroeck sizeof(ident)) ? -EFAULT : 0; 407b7e04f8cSWim Van Sebroeck case WDIOC_GETSTATUS: 408b7e04f8cSWim Van Sebroeck return put_user(pc87413_status(), uarg.i); 409b7e04f8cSWim Van Sebroeck case WDIOC_GETBOOTSTATUS: 410b7e04f8cSWim Van Sebroeck return put_user(0, uarg.i); 4110c06090cSWim Van Sebroeck case WDIOC_SETOPTIONS: 4120c06090cSWim Van Sebroeck { 4130c06090cSWim Van Sebroeck int options, retval = -EINVAL; 4140c06090cSWim Van Sebroeck if (get_user(options, uarg.i)) 4150c06090cSWim Van Sebroeck return -EFAULT; 4160c06090cSWim Van Sebroeck if (options & WDIOS_DISABLECARD) { 4170c06090cSWim Van Sebroeck pc87413_disable(); 4180c06090cSWim Van Sebroeck retval = 0; 4190c06090cSWim Van Sebroeck } 4200c06090cSWim Van Sebroeck if (options & WDIOS_ENABLECARD) { 4210c06090cSWim Van Sebroeck pc87413_enable(); 4220c06090cSWim Van Sebroeck retval = 0; 4230c06090cSWim Van Sebroeck } 4240c06090cSWim Van Sebroeck return retval; 4250c06090cSWim Van Sebroeck } 426b7e04f8cSWim Van Sebroeck case WDIOC_KEEPALIVE: 427b7e04f8cSWim Van Sebroeck pc87413_refresh(); 428b7e04f8cSWim Van Sebroeck #ifdef DEBUG 42927c766aaSJoe Perches pr_info(DPFX "keepalive\n"); 430b7e04f8cSWim Van Sebroeck #endif 431b7e04f8cSWim Van Sebroeck return 0; 432b7e04f8cSWim Van Sebroeck case WDIOC_SETTIMEOUT: 433b7e04f8cSWim Van Sebroeck if (get_user(new_timeout, uarg.i)) 434b7e04f8cSWim Van Sebroeck return -EFAULT; 435aee334c2SAlan Cox /* the API states this is given in secs */ 436b7e04f8cSWim Van Sebroeck new_timeout /= 60; 437b7e04f8cSWim Van Sebroeck if (new_timeout < 0 || new_timeout > MAX_TIMEOUT) 438b7e04f8cSWim Van Sebroeck return -EINVAL; 439b7e04f8cSWim Van Sebroeck timeout = new_timeout; 440b7e04f8cSWim Van Sebroeck pc87413_refresh(); 441aee334c2SAlan Cox /* fall through and return the new timeout... */ 442b7e04f8cSWim Van Sebroeck case WDIOC_GETTIMEOUT: 443b7e04f8cSWim Van Sebroeck new_timeout = timeout * 60; 444b7e04f8cSWim Van Sebroeck return put_user(new_timeout, uarg.i); 445aee334c2SAlan Cox default: 446aee334c2SAlan Cox return -ENOTTY; 447b7e04f8cSWim Van Sebroeck } 448b7e04f8cSWim Van Sebroeck } 449b7e04f8cSWim Van Sebroeck 450b7e04f8cSWim Van Sebroeck /* -- Notifier funtions -----------------------------------------*/ 451b7e04f8cSWim Van Sebroeck 452b7e04f8cSWim Van Sebroeck /** 453b7e04f8cSWim Van Sebroeck * notify_sys: 454b7e04f8cSWim Van Sebroeck * @this: our notifier block 455b7e04f8cSWim Van Sebroeck * @code: the event being reported 456b7e04f8cSWim Van Sebroeck * @unused: unused 457b7e04f8cSWim Van Sebroeck * 458b7e04f8cSWim Van Sebroeck * Our notifier is called on system shutdowns. We want to turn the card 459b7e04f8cSWim Van Sebroeck * off at reboot otherwise the machine will reboot again during memory 460b7e04f8cSWim Van Sebroeck * test or worse yet during the following fsck. This would suck, in fact 461b7e04f8cSWim Van Sebroeck * trust me - if it happens it does suck. 462b7e04f8cSWim Van Sebroeck */ 463b7e04f8cSWim Van Sebroeck 464b7e04f8cSWim Van Sebroeck static int pc87413_notify_sys(struct notifier_block *this, 465b7e04f8cSWim Van Sebroeck unsigned long code, 466b7e04f8cSWim Van Sebroeck void *unused) 467b7e04f8cSWim Van Sebroeck { 468b7e04f8cSWim Van Sebroeck if (code == SYS_DOWN || code == SYS_HALT) 469b7e04f8cSWim Van Sebroeck /* Turn the card off */ 470b7e04f8cSWim Van Sebroeck pc87413_disable(); 471b7e04f8cSWim Van Sebroeck return NOTIFY_DONE; 472b7e04f8cSWim Van Sebroeck } 473b7e04f8cSWim Van Sebroeck 474b7e04f8cSWim Van Sebroeck /* -- Module's structures ---------------------------------------*/ 475b7e04f8cSWim Van Sebroeck 476b7e04f8cSWim Van Sebroeck static const struct file_operations pc87413_fops = { 477b7e04f8cSWim Van Sebroeck .owner = THIS_MODULE, 478b7e04f8cSWim Van Sebroeck .llseek = no_llseek, 479b7e04f8cSWim Van Sebroeck .write = pc87413_write, 480aee334c2SAlan Cox .unlocked_ioctl = pc87413_ioctl, 481b7e04f8cSWim Van Sebroeck .open = pc87413_open, 482b7e04f8cSWim Van Sebroeck .release = pc87413_release, 483b7e04f8cSWim Van Sebroeck }; 484b7e04f8cSWim Van Sebroeck 485aee334c2SAlan Cox static struct notifier_block pc87413_notifier = { 486b7e04f8cSWim Van Sebroeck .notifier_call = pc87413_notify_sys, 487b7e04f8cSWim Van Sebroeck }; 488b7e04f8cSWim Van Sebroeck 489aee334c2SAlan Cox static struct miscdevice pc87413_miscdev = { 490b7e04f8cSWim Van Sebroeck .minor = WATCHDOG_MINOR, 491b7e04f8cSWim Van Sebroeck .name = "watchdog", 4927944d3a5SWim Van Sebroeck .fops = &pc87413_fops, 493b7e04f8cSWim Van Sebroeck }; 494b7e04f8cSWim Van Sebroeck 495b7e04f8cSWim Van Sebroeck /* -- Module init functions -------------------------------------*/ 496b7e04f8cSWim Van Sebroeck 497b7e04f8cSWim Van Sebroeck /** 498b7e04f8cSWim Van Sebroeck * pc87413_init: module's "constructor" 499b7e04f8cSWim Van Sebroeck * 500b7e04f8cSWim Van Sebroeck * Set up the WDT watchdog board. All we have to do is grab the 501b7e04f8cSWim Van Sebroeck * resources we require and bitch if anyone beat us to them. 502b7e04f8cSWim Van Sebroeck * The open() function will actually kick the board off. 503b7e04f8cSWim Van Sebroeck */ 504b7e04f8cSWim Van Sebroeck 505b7e04f8cSWim Van Sebroeck static int __init pc87413_init(void) 506b7e04f8cSWim Van Sebroeck { 507b7e04f8cSWim Van Sebroeck int ret; 508b7e04f8cSWim Van Sebroeck 50927c766aaSJoe Perches pr_info("Version " VERSION " at io 0x%X\n", 510aee334c2SAlan Cox WDT_INDEX_IO_PORT); 511b7e04f8cSWim Van Sebroeck 5127ccdb946SJonathan McDowell if (!request_muxed_region(io, 2, MODNAME)) 5137ccdb946SJonathan McDowell return -EBUSY; 514b7e04f8cSWim Van Sebroeck 515b7e04f8cSWim Van Sebroeck ret = register_reboot_notifier(&pc87413_notifier); 516b7e04f8cSWim Van Sebroeck if (ret != 0) { 51727c766aaSJoe Perches pr_err("cannot register reboot notifier (err=%d)\n", ret); 518b7e04f8cSWim Van Sebroeck } 519b7e04f8cSWim Van Sebroeck 520b7e04f8cSWim Van Sebroeck ret = misc_register(&pc87413_miscdev); 521b7e04f8cSWim Van Sebroeck if (ret != 0) { 52227c766aaSJoe Perches pr_err("cannot register miscdev on minor=%d (err=%d)\n", 523b7e04f8cSWim Van Sebroeck WATCHDOG_MINOR, ret); 5247ccdb946SJonathan McDowell goto reboot_unreg; 525b7e04f8cSWim Van Sebroeck } 52627c766aaSJoe Perches pr_info("initialized. timeout=%d min\n", timeout); 5277ccdb946SJonathan McDowell 5287ccdb946SJonathan McDowell pc87413_select_wdt_out(); 5297ccdb946SJonathan McDowell pc87413_enable_swc(); 5307ccdb946SJonathan McDowell pc87413_get_swc_base_addr(); 5317ccdb946SJonathan McDowell 5327ccdb946SJonathan McDowell if (!request_region(swc_base_addr, 0x20, MODNAME)) { 53327c766aaSJoe Perches pr_err("cannot request SWC region at 0x%x\n", swc_base_addr); 5347ccdb946SJonathan McDowell ret = -EBUSY; 5357ccdb946SJonathan McDowell goto misc_unreg; 5367ccdb946SJonathan McDowell } 5377ccdb946SJonathan McDowell 538b7e04f8cSWim Van Sebroeck pc87413_enable(); 5397ccdb946SJonathan McDowell 5407ccdb946SJonathan McDowell release_region(io, 2); 541b7e04f8cSWim Van Sebroeck return 0; 5427ccdb946SJonathan McDowell 5437ccdb946SJonathan McDowell misc_unreg: 5447ccdb946SJonathan McDowell misc_deregister(&pc87413_miscdev); 5457ccdb946SJonathan McDowell reboot_unreg: 5467ccdb946SJonathan McDowell unregister_reboot_notifier(&pc87413_notifier); 5477ccdb946SJonathan McDowell release_region(io, 2); 5487ccdb946SJonathan McDowell return ret; 549b7e04f8cSWim Van Sebroeck } 550b7e04f8cSWim Van Sebroeck 551b7e04f8cSWim Van Sebroeck /** 552b7e04f8cSWim Van Sebroeck * pc87413_exit: module's "destructor" 553b7e04f8cSWim Van Sebroeck * 554b7e04f8cSWim Van Sebroeck * Unload the watchdog. You cannot do this with any file handles open. 555b7e04f8cSWim Van Sebroeck * If your watchdog is set to continue ticking on close and you unload 556b7e04f8cSWim Van Sebroeck * it, well it keeps ticking. We won't get the interrupt but the board 557b7e04f8cSWim Van Sebroeck * will not touch PC memory so all is fine. You just have to load a new 558b7e04f8cSWim Van Sebroeck * module in 60 seconds or reboot. 559b7e04f8cSWim Van Sebroeck */ 560b7e04f8cSWim Van Sebroeck 561b7e04f8cSWim Van Sebroeck static void __exit pc87413_exit(void) 562b7e04f8cSWim Van Sebroeck { 563b7e04f8cSWim Van Sebroeck /* Stop the timer before we leave */ 564aee334c2SAlan Cox if (!nowayout) { 565b7e04f8cSWim Van Sebroeck pc87413_disable(); 56627c766aaSJoe Perches pr_info("Watchdog disabled\n"); 567b7e04f8cSWim Van Sebroeck } 568b7e04f8cSWim Van Sebroeck 569b7e04f8cSWim Van Sebroeck misc_deregister(&pc87413_miscdev); 570b7e04f8cSWim Van Sebroeck unregister_reboot_notifier(&pc87413_notifier); 5717ccdb946SJonathan McDowell release_region(swc_base_addr, 0x20); 572b7e04f8cSWim Van Sebroeck 57327c766aaSJoe Perches pr_info("watchdog component driver removed\n"); 574b7e04f8cSWim Van Sebroeck } 575b7e04f8cSWim Van Sebroeck 576b7e04f8cSWim Van Sebroeck module_init(pc87413_init); 577b7e04f8cSWim Van Sebroeck module_exit(pc87413_exit); 578b7e04f8cSWim Van Sebroeck 579143a2e54SWim Van Sebroeck MODULE_AUTHOR("Sven Anders <anders@anduras.de>, " 580143a2e54SWim Van Sebroeck "Marcus Junker <junker@anduras.de>,"); 581b7e04f8cSWim Van Sebroeck MODULE_DESCRIPTION("PC87413 WDT driver"); 582b7e04f8cSWim Van Sebroeck MODULE_LICENSE("GPL"); 583b7e04f8cSWim Van Sebroeck 584b7e04f8cSWim Van Sebroeck MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); 585b7e04f8cSWim Van Sebroeck 586b7e04f8cSWim Van Sebroeck module_param(io, int, 0); 58776550d32SRandy Dunlap MODULE_PARM_DESC(io, MODNAME " I/O port (default: " 58876550d32SRandy Dunlap __MODULE_STRING(IO_DEFAULT) ")."); 589b7e04f8cSWim Van Sebroeck 590b7e04f8cSWim Van Sebroeck module_param(timeout, int, 0); 591aee334c2SAlan Cox MODULE_PARM_DESC(timeout, 592aee334c2SAlan Cox "Watchdog timeout in minutes (default=" 59376550d32SRandy Dunlap __MODULE_STRING(DEFAULT_TIMEOUT) ")."); 594b7e04f8cSWim Van Sebroeck 59586a1e189SWim Van Sebroeck module_param(nowayout, bool, 0); 596aee334c2SAlan Cox MODULE_PARM_DESC(nowayout, 597aee334c2SAlan Cox "Watchdog cannot be stopped once started (default=" 598aee334c2SAlan Cox __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); 599b7e04f8cSWim Van Sebroeck 600