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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (C) 2016 National Instruments Corp.4 */5 6#include <linux/acpi.h>7#include <linux/device.h>8#include <linux/interrupt.h>9#include <linux/io.h>10#include <linux/module.h>11#include <linux/watchdog.h>12 13#define NIWD_CONTROL 0x0114#define NIWD_COUNTER2 0x0215#define NIWD_COUNTER1 0x0316#define NIWD_COUNTER0 0x0417#define NIWD_SEED2 0x0518#define NIWD_SEED1 0x0619#define NIWD_SEED0 0x0720 21#define NIWD_IO_SIZE 0x0822 23#define NIWD_CONTROL_MODE 0x8024#define NIWD_CONTROL_PROC_RESET 0x2025#define NIWD_CONTROL_PET 0x1026#define NIWD_CONTROL_RUNNING 0x0827#define NIWD_CONTROL_CAPTURECOUNTER 0x0428#define NIWD_CONTROL_RESET 0x0229#define NIWD_CONTROL_ALARM 0x0130 31#define NIWD_PERIOD_NS 3072032#define NIWD_MIN_TIMEOUT 133#define NIWD_MAX_TIMEOUT 51534#define NIWD_DEFAULT_TIMEOUT 6035 36#define NIWD_NAME "ni903x_wdt"37 38struct ni903x_wdt {39 struct device *dev;40 u16 io_base;41 struct watchdog_device wdd;42};43 44static unsigned int timeout;45module_param(timeout, uint, 0);46MODULE_PARM_DESC(timeout,47 "Watchdog timeout in seconds. (default="48 __MODULE_STRING(NIWD_DEFAULT_TIMEOUT) ")");49 50static int nowayout = WATCHDOG_NOWAYOUT;51module_param(nowayout, int, S_IRUGO);52MODULE_PARM_DESC(nowayout,53 "Watchdog cannot be stopped once started (default="54 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");55 56static void ni903x_start(struct ni903x_wdt *wdt)57{58 u8 control = inb(wdt->io_base + NIWD_CONTROL);59 60 outb(control | NIWD_CONTROL_RESET, wdt->io_base + NIWD_CONTROL);61 outb(control | NIWD_CONTROL_PET, wdt->io_base + NIWD_CONTROL);62}63 64static int ni903x_wdd_set_timeout(struct watchdog_device *wdd,65 unsigned int timeout)66{67 struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);68 u32 counter = timeout * (1000000000 / NIWD_PERIOD_NS);69 70 outb(((0x00FF0000 & counter) >> 16), wdt->io_base + NIWD_SEED2);71 outb(((0x0000FF00 & counter) >> 8), wdt->io_base + NIWD_SEED1);72 outb((0x000000FF & counter), wdt->io_base + NIWD_SEED0);73 74 wdd->timeout = timeout;75 76 return 0;77}78 79static unsigned int ni903x_wdd_get_timeleft(struct watchdog_device *wdd)80{81 struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);82 u8 control, counter0, counter1, counter2;83 u32 counter;84 85 control = inb(wdt->io_base + NIWD_CONTROL);86 control |= NIWD_CONTROL_CAPTURECOUNTER;87 outb(control, wdt->io_base + NIWD_CONTROL);88 89 counter2 = inb(wdt->io_base + NIWD_COUNTER2);90 counter1 = inb(wdt->io_base + NIWD_COUNTER1);91 counter0 = inb(wdt->io_base + NIWD_COUNTER0);92 93 counter = (counter2 << 16) | (counter1 << 8) | counter0;94 95 return counter / (1000000000 / NIWD_PERIOD_NS);96}97 98static int ni903x_wdd_ping(struct watchdog_device *wdd)99{100 struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);101 u8 control;102 103 control = inb(wdt->io_base + NIWD_CONTROL);104 outb(control | NIWD_CONTROL_PET, wdt->io_base + NIWD_CONTROL);105 106 return 0;107}108 109static int ni903x_wdd_start(struct watchdog_device *wdd)110{111 struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);112 113 outb(NIWD_CONTROL_RESET | NIWD_CONTROL_PROC_RESET,114 wdt->io_base + NIWD_CONTROL);115 116 ni903x_wdd_set_timeout(wdd, wdd->timeout);117 ni903x_start(wdt);118 119 return 0;120}121 122static int ni903x_wdd_stop(struct watchdog_device *wdd)123{124 struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);125 126 outb(NIWD_CONTROL_RESET, wdt->io_base + NIWD_CONTROL);127 128 return 0;129}130 131static acpi_status ni903x_resources(struct acpi_resource *res, void *data)132{133 struct ni903x_wdt *wdt = data;134 u16 io_size;135 136 switch (res->type) {137 case ACPI_RESOURCE_TYPE_IO:138 if (wdt->io_base != 0) {139 dev_err(wdt->dev, "too many IO resources\n");140 return AE_ERROR;141 }142 143 wdt->io_base = res->data.io.minimum;144 io_size = res->data.io.address_length;145 146 if (io_size < NIWD_IO_SIZE) {147 dev_err(wdt->dev, "memory region too small\n");148 return AE_ERROR;149 }150 151 if (!devm_request_region(wdt->dev, wdt->io_base, io_size,152 NIWD_NAME)) {153 dev_err(wdt->dev, "failed to get memory region\n");154 return AE_ERROR;155 }156 157 return AE_OK;158 159 case ACPI_RESOURCE_TYPE_END_TAG:160 default:161 /* Ignore unsupported resources, e.g. IRQ */162 return AE_OK;163 }164}165 166static const struct watchdog_info ni903x_wdd_info = {167 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,168 .identity = "NI Watchdog",169};170 171static const struct watchdog_ops ni903x_wdd_ops = {172 .owner = THIS_MODULE,173 .start = ni903x_wdd_start,174 .stop = ni903x_wdd_stop,175 .ping = ni903x_wdd_ping,176 .set_timeout = ni903x_wdd_set_timeout,177 .get_timeleft = ni903x_wdd_get_timeleft,178};179 180static int ni903x_acpi_add(struct acpi_device *device)181{182 struct device *dev = &device->dev;183 struct watchdog_device *wdd;184 struct ni903x_wdt *wdt;185 acpi_status status;186 int ret;187 188 wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);189 if (!wdt)190 return -ENOMEM;191 192 device->driver_data = wdt;193 wdt->dev = dev;194 195 status = acpi_walk_resources(device->handle, METHOD_NAME__CRS,196 ni903x_resources, wdt);197 if (ACPI_FAILURE(status) || wdt->io_base == 0) {198 dev_err(dev, "failed to get resources\n");199 return -ENODEV;200 }201 202 wdd = &wdt->wdd;203 wdd->info = &ni903x_wdd_info;204 wdd->ops = &ni903x_wdd_ops;205 wdd->min_timeout = NIWD_MIN_TIMEOUT;206 wdd->max_timeout = NIWD_MAX_TIMEOUT;207 wdd->timeout = NIWD_DEFAULT_TIMEOUT;208 wdd->parent = dev;209 watchdog_set_drvdata(wdd, wdt);210 watchdog_set_nowayout(wdd, nowayout);211 watchdog_init_timeout(wdd, timeout, dev);212 213 ret = watchdog_register_device(wdd);214 if (ret)215 return ret;216 217 /* Switch from boot mode to user mode */218 outb(NIWD_CONTROL_RESET | NIWD_CONTROL_MODE,219 wdt->io_base + NIWD_CONTROL);220 221 dev_dbg(dev, "io_base=0x%04X, timeout=%d, nowayout=%d\n",222 wdt->io_base, timeout, nowayout);223 224 return 0;225}226 227static void ni903x_acpi_remove(struct acpi_device *device)228{229 struct ni903x_wdt *wdt = acpi_driver_data(device);230 231 ni903x_wdd_stop(&wdt->wdd);232 watchdog_unregister_device(&wdt->wdd);233}234 235static const struct acpi_device_id ni903x_device_ids[] = {236 {"NIC775C", 0},237 {"", 0},238};239MODULE_DEVICE_TABLE(acpi, ni903x_device_ids);240 241static struct acpi_driver ni903x_acpi_driver = {242 .name = NIWD_NAME,243 .ids = ni903x_device_ids,244 .ops = {245 .add = ni903x_acpi_add,246 .remove = ni903x_acpi_remove,247 },248};249 250module_acpi_driver(ni903x_acpi_driver);251 252MODULE_DESCRIPTION("NI 903x Watchdog");253MODULE_AUTHOR("Jeff Westfahl <jeff.westfahl@ni.com>");254MODULE_AUTHOR("Kyle Roeschley <kyle.roeschley@ni.com>");255MODULE_LICENSE("GPL");256