mirror of
https://github.com/torvalds/linux.git
synced 2024-11-14 16:12:02 +00:00
625e407ce0
The struct tqmx86_wdt_ops is only assigned to the ops pointer in the watchdog_device struct, which is a pointer to const struct watchdog_ops. Make it const to allow the compiler to put it in read-only memory. Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20210727223042.48150-3-rikard.falkeborn@gmail.com Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
127 lines
2.9 KiB
C
127 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* Watchdog driver for TQMx86 PLD.
|
|
*
|
|
* The watchdog supports power of 2 timeouts from 1 to 4096sec.
|
|
* Once started, it cannot be stopped.
|
|
*
|
|
* Based on the vendor code written by Vadim V.Vlasov
|
|
* <vvlasov@dev.rtsoft.ru>
|
|
*/
|
|
|
|
#include <linux/io.h>
|
|
#include <linux/log2.h>
|
|
#include <linux/module.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/timer.h>
|
|
#include <linux/watchdog.h>
|
|
|
|
/* default timeout (secs) */
|
|
#define WDT_TIMEOUT 32
|
|
|
|
static unsigned int timeout;
|
|
module_param(timeout, uint, 0);
|
|
MODULE_PARM_DESC(timeout,
|
|
"Watchdog timeout in seconds. (1<=timeout<=4096, default="
|
|
__MODULE_STRING(WDT_TIMEOUT) ")");
|
|
struct tqmx86_wdt {
|
|
struct watchdog_device wdd;
|
|
void __iomem *io_base;
|
|
};
|
|
|
|
#define TQMX86_WDCFG 0x00 /* Watchdog Configuration Register */
|
|
#define TQMX86_WDCS 0x01 /* Watchdog Config/Status Register */
|
|
|
|
static int tqmx86_wdt_start(struct watchdog_device *wdd)
|
|
{
|
|
struct tqmx86_wdt *priv = watchdog_get_drvdata(wdd);
|
|
|
|
iowrite8(0x81, priv->io_base + TQMX86_WDCS);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int tqmx86_wdt_set_timeout(struct watchdog_device *wdd, unsigned int t)
|
|
{
|
|
struct tqmx86_wdt *priv = watchdog_get_drvdata(wdd);
|
|
u8 val;
|
|
|
|
t = roundup_pow_of_two(t);
|
|
val = ilog2(t) | 0x90;
|
|
val += 3; /* values 0,1,2 correspond to 0.125,0.25,0.5s timeouts */
|
|
iowrite8(val, priv->io_base + TQMX86_WDCFG);
|
|
|
|
wdd->timeout = t;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct watchdog_info tqmx86_wdt_info = {
|
|
.options = WDIOF_SETTIMEOUT |
|
|
WDIOF_KEEPALIVEPING,
|
|
.identity = "TQMx86 Watchdog",
|
|
};
|
|
|
|
static const struct watchdog_ops tqmx86_wdt_ops = {
|
|
.owner = THIS_MODULE,
|
|
.start = tqmx86_wdt_start,
|
|
.set_timeout = tqmx86_wdt_set_timeout,
|
|
};
|
|
|
|
static int tqmx86_wdt_probe(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct tqmx86_wdt *priv;
|
|
struct resource *res;
|
|
int err;
|
|
|
|
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
|
|
if (!priv)
|
|
return -ENOMEM;
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_IO, 0);
|
|
if (!res)
|
|
return -ENODEV;
|
|
|
|
priv->io_base = devm_ioport_map(dev, res->start, resource_size(res));
|
|
if (!priv->io_base)
|
|
return -ENOMEM;
|
|
|
|
watchdog_set_drvdata(&priv->wdd, priv);
|
|
|
|
priv->wdd.parent = dev;
|
|
priv->wdd.info = &tqmx86_wdt_info;
|
|
priv->wdd.ops = &tqmx86_wdt_ops;
|
|
priv->wdd.min_timeout = 1;
|
|
priv->wdd.max_timeout = 4096;
|
|
priv->wdd.max_hw_heartbeat_ms = 4096*1000;
|
|
priv->wdd.timeout = WDT_TIMEOUT;
|
|
|
|
watchdog_init_timeout(&priv->wdd, timeout, dev);
|
|
watchdog_set_nowayout(&priv->wdd, WATCHDOG_NOWAYOUT);
|
|
|
|
tqmx86_wdt_set_timeout(&priv->wdd, priv->wdd.timeout);
|
|
|
|
err = devm_watchdog_register_device(dev, &priv->wdd);
|
|
if (err)
|
|
return err;
|
|
|
|
dev_info(dev, "TQMx86 watchdog\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver tqmx86_wdt_driver = {
|
|
.driver = {
|
|
.name = "tqmx86-wdt",
|
|
},
|
|
.probe = tqmx86_wdt_probe,
|
|
};
|
|
|
|
module_platform_driver(tqmx86_wdt_driver);
|
|
|
|
MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
|
|
MODULE_DESCRIPTION("TQMx86 Watchdog");
|
|
MODULE_ALIAS("platform:tqmx86-wdt");
|
|
MODULE_LICENSE("GPL");
|