linux/drivers/watchdog/nic7018_wdt.c

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 Based on 3 normalized pattern(s): 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 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 [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] 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 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 [author] [graeme] [gregory] [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema] [hk] [hemahk]@[ti] [com] 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1105 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-27 06:55:06 +00:00
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2016 National Instruments Corp.
*/
#include <linux/acpi.h>
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/watchdog.h>
#define LOCK 0xA5
#define UNLOCK 0x5A
#define WDT_CTRL_RESET_EN BIT(7)
#define WDT_RELOAD_PORT_EN BIT(7)
#define WDT_CTRL 1
#define WDT_RELOAD_CTRL 2
#define WDT_PRESET_PRESCALE 4
#define WDT_REG_LOCK 5
#define WDT_COUNT 6
#define WDT_RELOAD_PORT 7
#define WDT_MIN_TIMEOUT 1
#define WDT_MAX_TIMEOUT 464
#define WDT_DEFAULT_TIMEOUT 80
#define WDT_MAX_COUNTER 15
static unsigned int timeout;
module_param(timeout, uint, 0);
MODULE_PARM_DESC(timeout,
"Watchdog timeout in seconds. (default="
__MODULE_STRING(WDT_DEFAULT_TIMEOUT) ")");
static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout,
"Watchdog cannot be stopped once started. (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
struct nic7018_wdt {
u16 io_base;
u32 period;
struct watchdog_device wdd;
};
struct nic7018_config {
u32 period;
u8 divider;
};
static const struct nic7018_config nic7018_configs[] = {
{ 2, 4 },
{ 32, 5 },
};
static inline u32 nic7018_timeout(u32 period, u8 counter)
{
return period * counter - period / 2;
}
static const struct nic7018_config *nic7018_get_config(u32 timeout,
u8 *counter)
{
const struct nic7018_config *config;
u8 count;
if (timeout < 30 && timeout != 16) {
config = &nic7018_configs[0];
count = timeout / 2 + 1;
} else {
config = &nic7018_configs[1];
count = DIV_ROUND_UP(timeout + 16, 32);
if (count > WDT_MAX_COUNTER)
count = WDT_MAX_COUNTER;
}
*counter = count;
return config;
}
static int nic7018_set_timeout(struct watchdog_device *wdd,
unsigned int timeout)
{
struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
const struct nic7018_config *config;
u8 counter;
config = nic7018_get_config(timeout, &counter);
outb(counter << 4 | config->divider,
wdt->io_base + WDT_PRESET_PRESCALE);
wdd->timeout = nic7018_timeout(config->period, counter);
wdt->period = config->period;
return 0;
}
static int nic7018_start(struct watchdog_device *wdd)
{
struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
u8 control;
nic7018_set_timeout(wdd, wdd->timeout);
control = inb(wdt->io_base + WDT_RELOAD_CTRL);
outb(control | WDT_RELOAD_PORT_EN, wdt->io_base + WDT_RELOAD_CTRL);
outb(1, wdt->io_base + WDT_RELOAD_PORT);
control = inb(wdt->io_base + WDT_CTRL);
outb(control | WDT_CTRL_RESET_EN, wdt->io_base + WDT_CTRL);
return 0;
}
static int nic7018_stop(struct watchdog_device *wdd)
{
struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
outb(0, wdt->io_base + WDT_CTRL);
outb(0, wdt->io_base + WDT_RELOAD_CTRL);
outb(0xF0, wdt->io_base + WDT_PRESET_PRESCALE);
return 0;
}
static int nic7018_ping(struct watchdog_device *wdd)
{
struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
outb(1, wdt->io_base + WDT_RELOAD_PORT);
return 0;
}
static unsigned int nic7018_get_timeleft(struct watchdog_device *wdd)
{
struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
u8 count;
count = inb(wdt->io_base + WDT_COUNT) & 0xF;
if (!count)
return 0;
return nic7018_timeout(wdt->period, count);
}
static const struct watchdog_info nic7018_wdd_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
.identity = "NIC7018 Watchdog",
};
static const struct watchdog_ops nic7018_wdd_ops = {
.owner = THIS_MODULE,
.start = nic7018_start,
.stop = nic7018_stop,
.ping = nic7018_ping,
.set_timeout = nic7018_set_timeout,
.get_timeleft = nic7018_get_timeleft,
};
static int nic7018_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct watchdog_device *wdd;
struct nic7018_wdt *wdt;
struct resource *io_rc;
int ret;
wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
if (!wdt)
return -ENOMEM;
platform_set_drvdata(pdev, wdt);
io_rc = platform_get_resource(pdev, IORESOURCE_IO, 0);
if (!io_rc) {
dev_err(dev, "missing IO resources\n");
return -EINVAL;
}
if (!devm_request_region(dev, io_rc->start, resource_size(io_rc),
KBUILD_MODNAME)) {
dev_err(dev, "failed to get IO region\n");
return -EBUSY;
}
wdt->io_base = io_rc->start;
wdd = &wdt->wdd;
wdd->info = &nic7018_wdd_info;
wdd->ops = &nic7018_wdd_ops;
wdd->min_timeout = WDT_MIN_TIMEOUT;
wdd->max_timeout = WDT_MAX_TIMEOUT;
wdd->timeout = WDT_DEFAULT_TIMEOUT;
wdd->parent = dev;
watchdog_set_drvdata(wdd, wdt);
watchdog_set_nowayout(wdd, nowayout);
watchdog_init_timeout(wdd, timeout, dev);
/* Unlock WDT register */
outb(UNLOCK, wdt->io_base + WDT_REG_LOCK);
ret = watchdog_register_device(wdd);
if (ret) {
outb(LOCK, wdt->io_base + WDT_REG_LOCK);
return ret;
}
dev_dbg(dev, "io_base=0x%04X, timeout=%d, nowayout=%d\n",
wdt->io_base, timeout, nowayout);
return 0;
}
static int nic7018_remove(struct platform_device *pdev)
{
struct nic7018_wdt *wdt = platform_get_drvdata(pdev);
watchdog_unregister_device(&wdt->wdd);
/* Lock WDT register */
outb(LOCK, wdt->io_base + WDT_REG_LOCK);
return 0;
}
static const struct acpi_device_id nic7018_device_ids[] = {
{"NIC7018", 0},
{"", 0},
};
MODULE_DEVICE_TABLE(acpi, nic7018_device_ids);
static struct platform_driver watchdog_driver = {
.probe = nic7018_probe,
.remove = nic7018_remove,
.driver = {
.name = KBUILD_MODNAME,
.acpi_match_table = ACPI_PTR(nic7018_device_ids),
},
};
module_platform_driver(watchdog_driver);
MODULE_DESCRIPTION("National Instruments NIC7018 Watchdog driver");
MODULE_AUTHOR("Hui Chun Ong <hui.chun.ong@ni.com>");
MODULE_LICENSE("GPL");