Loading...
1 2 3 4 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 32 33 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 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 | /* * Retu watchdog driver * * Copyright (C) 2004, 2005 Nokia Corporation * * Based on code written by Amit Kucheria and Michael Buesch. * Rewritten by Aaro Koskinen. * * This file is subject to the terms and conditions of the GNU General * Public License. See the file "COPYING" in the main directory of this * archive for more details. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include <linux/slab.h> #include <linux/errno.h> #include <linux/device.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/mfd/retu.h> #include <linux/watchdog.h> #include <linux/platform_device.h> /* Watchdog timer values in seconds */ #define RETU_WDT_MAX_TIMER 63 struct retu_wdt_dev { struct retu_dev *rdev; struct device *dev; struct delayed_work ping_work; }; /* * Since Retu watchdog cannot be disabled in hardware, we must kick it * with a timer until userspace watchdog software takes over. If * CONFIG_WATCHDOG_NOWAYOUT is set, we never start the feeding. */ static void retu_wdt_ping_enable(struct retu_wdt_dev *wdev) { retu_write(wdev->rdev, RETU_REG_WATCHDOG, RETU_WDT_MAX_TIMER); schedule_delayed_work(&wdev->ping_work, round_jiffies_relative(RETU_WDT_MAX_TIMER * HZ / 2)); } static void retu_wdt_ping_disable(struct retu_wdt_dev *wdev) { retu_write(wdev->rdev, RETU_REG_WATCHDOG, RETU_WDT_MAX_TIMER); cancel_delayed_work_sync(&wdev->ping_work); } static void retu_wdt_ping_work(struct work_struct *work) { struct retu_wdt_dev *wdev = container_of(to_delayed_work(work), struct retu_wdt_dev, ping_work); retu_wdt_ping_enable(wdev); } static int retu_wdt_start(struct watchdog_device *wdog) { struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog); retu_wdt_ping_disable(wdev); return retu_write(wdev->rdev, RETU_REG_WATCHDOG, wdog->timeout); } static int retu_wdt_stop(struct watchdog_device *wdog) { struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog); retu_wdt_ping_enable(wdev); return 0; } static int retu_wdt_ping(struct watchdog_device *wdog) { struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog); return retu_write(wdev->rdev, RETU_REG_WATCHDOG, wdog->timeout); } static int retu_wdt_set_timeout(struct watchdog_device *wdog, unsigned int timeout) { struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog); wdog->timeout = timeout; return retu_write(wdev->rdev, RETU_REG_WATCHDOG, wdog->timeout); } static const struct watchdog_info retu_wdt_info = { .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, .identity = "Retu watchdog", }; static const struct watchdog_ops retu_wdt_ops = { .owner = THIS_MODULE, .start = retu_wdt_start, .stop = retu_wdt_stop, .ping = retu_wdt_ping, .set_timeout = retu_wdt_set_timeout, }; static int retu_wdt_probe(struct platform_device *pdev) { struct retu_dev *rdev = dev_get_drvdata(pdev->dev.parent); bool nowayout = WATCHDOG_NOWAYOUT; struct watchdog_device *retu_wdt; struct retu_wdt_dev *wdev; int ret; retu_wdt = devm_kzalloc(&pdev->dev, sizeof(*retu_wdt), GFP_KERNEL); if (!retu_wdt) return -ENOMEM; wdev = devm_kzalloc(&pdev->dev, sizeof(*wdev), GFP_KERNEL); if (!wdev) return -ENOMEM; retu_wdt->info = &retu_wdt_info; retu_wdt->ops = &retu_wdt_ops; retu_wdt->timeout = RETU_WDT_MAX_TIMER; retu_wdt->min_timeout = 0; retu_wdt->max_timeout = RETU_WDT_MAX_TIMER; retu_wdt->parent = &pdev->dev; watchdog_set_drvdata(retu_wdt, wdev); watchdog_set_nowayout(retu_wdt, nowayout); wdev->rdev = rdev; wdev->dev = &pdev->dev; INIT_DELAYED_WORK(&wdev->ping_work, retu_wdt_ping_work); ret = watchdog_register_device(retu_wdt); if (ret < 0) return ret; if (nowayout) retu_wdt_ping(retu_wdt); else retu_wdt_ping_enable(wdev); platform_set_drvdata(pdev, retu_wdt); return 0; } static int retu_wdt_remove(struct platform_device *pdev) { struct watchdog_device *wdog = platform_get_drvdata(pdev); struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog); watchdog_unregister_device(wdog); cancel_delayed_work_sync(&wdev->ping_work); return 0; } static struct platform_driver retu_wdt_driver = { .probe = retu_wdt_probe, .remove = retu_wdt_remove, .driver = { .name = "retu-wdt", }, }; module_platform_driver(retu_wdt_driver); MODULE_ALIAS("platform:retu-wdt"); MODULE_DESCRIPTION("Retu watchdog"); MODULE_AUTHOR("Amit Kucheria"); MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>"); MODULE_LICENSE("GPL"); |