linux/drivers/watchdog/loongson1_wdt.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

159 lines
3.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) 2016 Yang Ling <gnaygnil@gmail.com>
*/
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/watchdog.h>
#include <loongson1.h>
#define DEFAULT_HEARTBEAT 30
static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0444);
static unsigned int heartbeat;
module_param(heartbeat, uint, 0444);
struct ls1x_wdt_drvdata {
void __iomem *base;
struct clk *clk;
unsigned long clk_rate;
struct watchdog_device wdt;
};
static int ls1x_wdt_ping(struct watchdog_device *wdt_dev)
{
struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
writel(0x1, drvdata->base + WDT_SET);
return 0;
}
static int ls1x_wdt_set_timeout(struct watchdog_device *wdt_dev,
unsigned int timeout)
{
struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
unsigned int max_hw_heartbeat = wdt_dev->max_hw_heartbeat_ms / 1000;
unsigned int counts;
wdt_dev->timeout = timeout;
counts = drvdata->clk_rate * min(timeout, max_hw_heartbeat);
writel(counts, drvdata->base + WDT_TIMER);
return 0;
}
static int ls1x_wdt_start(struct watchdog_device *wdt_dev)
{
struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
writel(0x1, drvdata->base + WDT_EN);
return 0;
}
static int ls1x_wdt_stop(struct watchdog_device *wdt_dev)
{
struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
writel(0x0, drvdata->base + WDT_EN);
return 0;
}
static const struct watchdog_info ls1x_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
.identity = "Loongson1 Watchdog",
};
static const struct watchdog_ops ls1x_wdt_ops = {
.owner = THIS_MODULE,
.start = ls1x_wdt_start,
.stop = ls1x_wdt_stop,
.ping = ls1x_wdt_ping,
.set_timeout = ls1x_wdt_set_timeout,
};
static void ls1x_clk_disable_unprepare(void *data)
{
clk_disable_unprepare(data);
}
static int ls1x_wdt_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct ls1x_wdt_drvdata *drvdata;
struct watchdog_device *ls1x_wdt;
unsigned long clk_rate;
int err;
drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
if (!drvdata)
return -ENOMEM;
drvdata->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(drvdata->base))
return PTR_ERR(drvdata->base);
drvdata->clk = devm_clk_get(dev, pdev->name);
if (IS_ERR(drvdata->clk))
return PTR_ERR(drvdata->clk);
err = clk_prepare_enable(drvdata->clk);
if (err) {
dev_err(dev, "clk enable failed\n");
return err;
}
err = devm_add_action_or_reset(dev, ls1x_clk_disable_unprepare,
drvdata->clk);
if (err)
return err;
clk_rate = clk_get_rate(drvdata->clk);
if (!clk_rate)
return -EINVAL;
drvdata->clk_rate = clk_rate;
ls1x_wdt = &drvdata->wdt;
ls1x_wdt->info = &ls1x_wdt_info;
ls1x_wdt->ops = &ls1x_wdt_ops;
ls1x_wdt->timeout = DEFAULT_HEARTBEAT;
ls1x_wdt->min_timeout = 1;
ls1x_wdt->max_hw_heartbeat_ms = U32_MAX / clk_rate * 1000;
ls1x_wdt->parent = dev;
watchdog_init_timeout(ls1x_wdt, heartbeat, dev);
watchdog_set_nowayout(ls1x_wdt, nowayout);
watchdog_set_drvdata(ls1x_wdt, drvdata);
err = devm_watchdog_register_device(dev, &drvdata->wdt);
if (err) {
dev_err(dev, "failed to register watchdog device\n");
return err;
}
platform_set_drvdata(pdev, drvdata);
dev_info(dev, "Loongson1 Watchdog driver registered\n");
return 0;
}
static struct platform_driver ls1x_wdt_driver = {
.probe = ls1x_wdt_probe,
.driver = {
.name = "ls1x-wdt",
},
};
module_platform_driver(ls1x_wdt_driver);
MODULE_AUTHOR("Yang Ling <gnaygnil@gmail.com>");
MODULE_DESCRIPTION("Loongson1 Watchdog Driver");
MODULE_LICENSE("GPL");