alistair23-linux/drivers/watchdog/twl4030_wdt.c
Guenter Roeck b42488bcd6 watchdog: twl4030_wdt: Convert to use device managed functions and other improvements
Use device managed functions to simplify error handling, reduce
source code size, improve readability, and reduce the likelyhood of bugs.
Other improvements as listed below.

The conversion was done automatically with coccinelle using the
following semantic patches. The semantic patches and the scripts
used to generate this commit log are available at
https://github.com/groeck/coccinelle-patches

- Drop assignments to otherwise unused variables
- Drop empty remove function
- Introduce local variable 'struct device *dev' and use it instead of
  dereferencing it repeatedly
- Use devm_watchdog_register_driver() to register watchdog device

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-05-05 21:02:32 +02:00

141 lines
3.6 KiB
C

/*
* Copyright (C) Nokia Corporation
*
* Written by Timo Kokkonen <timo.t.kokkonen at nokia.com>
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
#include <linux/mfd/twl.h>
#define TWL4030_WATCHDOG_CFG_REG_OFFS 0x3
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) ")");
static int twl4030_wdt_write(unsigned char val)
{
return twl_i2c_write_u8(TWL_MODULE_PM_RECEIVER, val,
TWL4030_WATCHDOG_CFG_REG_OFFS);
}
static int twl4030_wdt_start(struct watchdog_device *wdt)
{
return twl4030_wdt_write(wdt->timeout + 1);
}
static int twl4030_wdt_stop(struct watchdog_device *wdt)
{
return twl4030_wdt_write(0);
}
static int twl4030_wdt_set_timeout(struct watchdog_device *wdt,
unsigned int timeout)
{
wdt->timeout = timeout;
return 0;
}
static const struct watchdog_info twl4030_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
.identity = "TWL4030 Watchdog",
};
static const struct watchdog_ops twl4030_wdt_ops = {
.owner = THIS_MODULE,
.start = twl4030_wdt_start,
.stop = twl4030_wdt_stop,
.set_timeout = twl4030_wdt_set_timeout,
};
static int twl4030_wdt_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct watchdog_device *wdt;
wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
if (!wdt)
return -ENOMEM;
wdt->info = &twl4030_wdt_info;
wdt->ops = &twl4030_wdt_ops;
wdt->status = 0;
wdt->timeout = 30;
wdt->min_timeout = 1;
wdt->max_timeout = 30;
wdt->parent = dev;
watchdog_set_nowayout(wdt, nowayout);
platform_set_drvdata(pdev, wdt);
twl4030_wdt_stop(wdt);
return devm_watchdog_register_device(dev, wdt);
}
#ifdef CONFIG_PM
static int twl4030_wdt_suspend(struct platform_device *pdev, pm_message_t state)
{
struct watchdog_device *wdt = platform_get_drvdata(pdev);
if (watchdog_active(wdt))
return twl4030_wdt_stop(wdt);
return 0;
}
static int twl4030_wdt_resume(struct platform_device *pdev)
{
struct watchdog_device *wdt = platform_get_drvdata(pdev);
if (watchdog_active(wdt))
return twl4030_wdt_start(wdt);
return 0;
}
#else
#define twl4030_wdt_suspend NULL
#define twl4030_wdt_resume NULL
#endif
static const struct of_device_id twl_wdt_of_match[] = {
{ .compatible = "ti,twl4030-wdt", },
{ },
};
MODULE_DEVICE_TABLE(of, twl_wdt_of_match);
static struct platform_driver twl4030_wdt_driver = {
.probe = twl4030_wdt_probe,
.suspend = twl4030_wdt_suspend,
.resume = twl4030_wdt_resume,
.driver = {
.name = "twl4030_wdt",
.of_match_table = twl_wdt_of_match,
},
};
module_platform_driver(twl4030_wdt_driver);
MODULE_AUTHOR("Nokia Corporation");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:twl4030_wdt");