/* * Copyright (C) 2016 National Instruments Corp. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * 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/acpi.h> #include <linux/device.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/module.h> #include <linux/watchdog.h> #define NIWD_CONTROL 0x01 #define NIWD_COUNTER2 0x02 #define NIWD_COUNTER1 0x03 #define NIWD_COUNTER0 0x04 #define NIWD_SEED2 0x05 #define NIWD_SEED1 0x06 #define NIWD_SEED0 0x07 #define NIWD_IO_SIZE 0x08 #define NIWD_CONTROL_MODE 0x80 #define NIWD_CONTROL_PROC_RESET 0x20 #define NIWD_CONTROL_PET 0x10 #define NIWD_CONTROL_RUNNING 0x08 #define NIWD_CONTROL_CAPTURECOUNTER 0x04 #define NIWD_CONTROL_RESET 0x02 #define NIWD_CONTROL_ALARM 0x01 #define NIWD_PERIOD_NS 30720 #define NIWD_MIN_TIMEOUT 1 #define NIWD_MAX_TIMEOUT 515 #define NIWD_DEFAULT_TIMEOUT 60 #define NIWD_NAME "ni903x_wdt" struct ni903x_wdt { struct device *dev; u16 io_base; struct watchdog_device wdd; }; static unsigned int timeout; module_param(timeout, uint, 0); MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. (default=" __MODULE_STRING(NIWD_DEFAULT_TIMEOUT) ")"); static int nowayout = WATCHDOG_NOWAYOUT; module_param(nowayout, int, S_IRUGO); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); static void ni903x_start(struct ni903x_wdt *wdt) { u8 control = inb(wdt->io_base + NIWD_CONTROL); outb(control | NIWD_CONTROL_RESET, wdt->io_base + NIWD_CONTROL); outb(control | NIWD_CONTROL_PET, wdt->io_base + NIWD_CONTROL); } static int ni903x_wdd_set_timeout(struct watchdog_device *wdd, unsigned int timeout) { struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd); u32 counter = timeout * (1000000000 / NIWD_PERIOD_NS); outb(((0x00FF0000 & counter) >> 16), wdt->io_base + NIWD_SEED2); outb(((0x0000FF00 & counter) >> 8), wdt->io_base + NIWD_SEED1); outb((0x000000FF & counter), wdt->io_base + NIWD_SEED0); wdd->timeout = timeout; return 0; } static unsigned int ni903x_wdd_get_timeleft(struct watchdog_device *wdd) { struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd); u8 control, counter0, counter1, counter2; u32 counter; control = inb(wdt->io_base + NIWD_CONTROL); control |= NIWD_CONTROL_CAPTURECOUNTER; outb(control, wdt->io_base + NIWD_CONTROL); counter2 = inb(wdt->io_base + NIWD_COUNTER2); counter1 = inb(wdt->io_base + NIWD_COUNTER1); counter0 = inb(wdt->io_base + NIWD_COUNTER0); counter = (counter2 << 16) | (counter1 << 8) | counter0; return counter / (1000000000 / NIWD_PERIOD_NS); } static int ni903x_wdd_ping(struct watchdog_device *wdd) { struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd); u8 control; control = inb(wdt->io_base + NIWD_CONTROL); outb(control | NIWD_CONTROL_PET, wdt->io_base + NIWD_CONTROL); return 0; } static int ni903x_wdd_start(struct watchdog_device *wdd) { struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd); outb(NIWD_CONTROL_RESET | NIWD_CONTROL_PROC_RESET, wdt->io_base + NIWD_CONTROL); ni903x_wdd_set_timeout(wdd, wdd->timeout); ni903x_start(wdt); return 0; } static int ni903x_wdd_stop(struct watchdog_device *wdd) { struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd); outb(NIWD_CONTROL_RESET, wdt->io_base + NIWD_CONTROL); return 0; } static acpi_status ni903x_resources(struct acpi_resource *res, void *data) { struct ni903x_wdt *wdt = data; u16 io_size; switch (res->type) { case ACPI_RESOURCE_TYPE_IO: if (wdt->io_base != 0) { dev_err(wdt->dev, "too many IO resources\n"); return AE_ERROR; } wdt->io_base = res->data.io.minimum; io_size = res->data.io.address_length; if (io_size < NIWD_IO_SIZE) { dev_err(wdt->dev, "memory region too small\n"); return AE_ERROR; } if (!devm_request_region(wdt->dev, wdt->io_base, io_size, NIWD_NAME)) { dev_err(wdt->dev, "failed to get memory region\n"); return AE_ERROR; } return AE_OK; case ACPI_RESOURCE_TYPE_END_TAG: default: /* Ignore unsupported resources, e.g. IRQ */ return AE_OK; } } static const struct watchdog_info ni903x_wdd_info = { .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, .identity = "NI Watchdog", }; static const struct watchdog_ops ni903x_wdd_ops = { .owner = THIS_MODULE, .start = ni903x_wdd_start, .stop = ni903x_wdd_stop, .ping = ni903x_wdd_ping, .set_timeout = ni903x_wdd_set_timeout, .get_timeleft = ni903x_wdd_get_timeleft, }; static int ni903x_acpi_add(struct acpi_device *device) { struct device *dev = &device->dev; struct watchdog_device *wdd; struct ni903x_wdt *wdt; acpi_status status; int ret; wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL); if (!wdt) return -ENOMEM; device->driver_data = wdt; wdt->dev = dev; status = acpi_walk_resources(device->handle, METHOD_NAME__CRS, ni903x_resources, wdt); if (ACPI_FAILURE(status) || wdt->io_base == 0) { dev_err(dev, "failed to get resources\n"); return -ENODEV; } wdd = &wdt->wdd; wdd->info = &ni903x_wdd_info; wdd->ops = &ni903x_wdd_ops; wdd->min_timeout = NIWD_MIN_TIMEOUT; wdd->max_timeout = NIWD_MAX_TIMEOUT; wdd->timeout = NIWD_DEFAULT_TIMEOUT; wdd->parent = dev; watchdog_set_drvdata(wdd, wdt); watchdog_set_nowayout(wdd, nowayout); ret = watchdog_init_timeout(wdd, timeout, dev); if (ret) dev_err(dev, "unable to set timeout value, using default\n"); ret = watchdog_register_device(wdd); if (ret) { dev_err(dev, "failed to register watchdog\n"); return ret; } /* Switch from boot mode to user mode */ outb(NIWD_CONTROL_RESET | NIWD_CONTROL_MODE, wdt->io_base + NIWD_CONTROL); dev_dbg(dev, "io_base=0x%04X, timeout=%d, nowayout=%d\n", wdt->io_base, timeout, nowayout); return 0; } static int ni903x_acpi_remove(struct acpi_device *device) { struct ni903x_wdt *wdt = acpi_driver_data(device); ni903x_wdd_stop(&wdt->wdd); watchdog_unregister_device(&wdt->wdd); return 0; } static const struct acpi_device_id ni903x_device_ids[] = { {"NIC775C", 0}, {"", 0}, }; MODULE_DEVICE_TABLE(acpi, ni903x_device_ids); static struct acpi_driver ni903x_acpi_driver = { .name = NIWD_NAME, .ids = ni903x_device_ids, .ops = { .add = ni903x_acpi_add, .remove = ni903x_acpi_remove, }, }; module_acpi_driver(ni903x_acpi_driver); MODULE_DESCRIPTION("NI 903x Watchdog"); MODULE_AUTHOR("Jeff Westfahl <jeff.westfahl@ni.com>"); MODULE_AUTHOR("Kyle Roeschley <kyle.roeschley@ni.com>"); MODULE_LICENSE("GPL");