alistair23-linux/drivers/watchdog/stmp3xxx_rtc_wdt.c
Pratyush Anand 6551881c86 Watchdog: Fix parent of watchdog_devices
/sys/class/watchdog/watchdogn/device/modalias can help to identify the
driver/module for a given watchdog node. However, many wdt devices do not
set their parent and so, we do not see an entry for device in sysfs for
such devices.

This patch fixes parent of watchdog_device so that
/sys/class/watchdog/watchdogn/device is populated.

Exceptions: booke, diag288, octeon, softdog and w83627hf -- They do not
have any parent. Not sure, how we can identify driver for these devices.

Signed-off-by: Pratyush Anand <panand@redhat.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Maxime Coquelin <maxime.coquelin@st.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-09-09 21:39:22 +02:00

134 lines
3.4 KiB
C

/*
* Watchdog driver for the RTC based watchdog in STMP3xxx and i.MX23/28
*
* Author: Wolfram Sang <kernel@pengutronix.de>
*
* Copyright (C) 2011-12 Wolfram Sang, Pengutronix
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
#include <linux/stmp3xxx_rtc_wdt.h>
#define WDOG_TICK_RATE 1000 /* 1 kHz clock */
#define STMP3XXX_DEFAULT_TIMEOUT 19
#define STMP3XXX_MAX_TIMEOUT (UINT_MAX / WDOG_TICK_RATE)
static int heartbeat = STMP3XXX_DEFAULT_TIMEOUT;
module_param(heartbeat, uint, 0);
MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat period in seconds from 1 to "
__MODULE_STRING(STMP3XXX_MAX_TIMEOUT) ", default "
__MODULE_STRING(STMP3XXX_DEFAULT_TIMEOUT));
static int wdt_start(struct watchdog_device *wdd)
{
struct device *dev = watchdog_get_drvdata(wdd);
struct stmp3xxx_wdt_pdata *pdata = dev_get_platdata(dev);
pdata->wdt_set_timeout(dev->parent, wdd->timeout * WDOG_TICK_RATE);
return 0;
}
static int wdt_stop(struct watchdog_device *wdd)
{
struct device *dev = watchdog_get_drvdata(wdd);
struct stmp3xxx_wdt_pdata *pdata = dev_get_platdata(dev);
pdata->wdt_set_timeout(dev->parent, 0);
return 0;
}
static int wdt_set_timeout(struct watchdog_device *wdd, unsigned new_timeout)
{
wdd->timeout = new_timeout;
return wdt_start(wdd);
}
static const struct watchdog_info stmp3xxx_wdt_ident = {
.options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
.identity = "STMP3XXX RTC Watchdog",
};
static const struct watchdog_ops stmp3xxx_wdt_ops = {
.owner = THIS_MODULE,
.start = wdt_start,
.stop = wdt_stop,
.set_timeout = wdt_set_timeout,
};
static struct watchdog_device stmp3xxx_wdd = {
.info = &stmp3xxx_wdt_ident,
.ops = &stmp3xxx_wdt_ops,
.min_timeout = 1,
.max_timeout = STMP3XXX_MAX_TIMEOUT,
.status = WATCHDOG_NOWAYOUT_INIT_STATUS,
};
static int stmp3xxx_wdt_probe(struct platform_device *pdev)
{
int ret;
watchdog_set_drvdata(&stmp3xxx_wdd, &pdev->dev);
stmp3xxx_wdd.timeout = clamp_t(unsigned, heartbeat, 1, STMP3XXX_MAX_TIMEOUT);
stmp3xxx_wdd.parent = &pdev->dev;
ret = watchdog_register_device(&stmp3xxx_wdd);
if (ret < 0) {
dev_err(&pdev->dev, "cannot register watchdog device\n");
return ret;
}
dev_info(&pdev->dev, "initialized watchdog with heartbeat %ds\n",
stmp3xxx_wdd.timeout);
return 0;
}
static int stmp3xxx_wdt_remove(struct platform_device *pdev)
{
watchdog_unregister_device(&stmp3xxx_wdd);
return 0;
}
static int __maybe_unused stmp3xxx_wdt_suspend(struct device *dev)
{
struct watchdog_device *wdd = &stmp3xxx_wdd;
if (watchdog_active(wdd))
return wdt_stop(wdd);
return 0;
}
static int __maybe_unused stmp3xxx_wdt_resume(struct device *dev)
{
struct watchdog_device *wdd = &stmp3xxx_wdd;
if (watchdog_active(wdd))
return wdt_start(wdd);
return 0;
}
static SIMPLE_DEV_PM_OPS(stmp3xxx_wdt_pm_ops,
stmp3xxx_wdt_suspend, stmp3xxx_wdt_resume);
static struct platform_driver stmp3xxx_wdt_driver = {
.driver = {
.name = "stmp3xxx_rtc_wdt",
.pm = &stmp3xxx_wdt_pm_ops,
},
.probe = stmp3xxx_wdt_probe,
.remove = stmp3xxx_wdt_remove,
};
module_platform_driver(stmp3xxx_wdt_driver);
MODULE_DESCRIPTION("STMP3XXX RTC Watchdog Driver");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");