linux/drivers/watchdog/wm8350_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

182 lines
4.1 KiB
C

/*
* Watchdog driver for the wm8350
*
* Copyright (C) 2007, 2008 Wolfson Microelectronics <linux@wolfsonmicro.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
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/watchdog.h>
#include <linux/uaccess.h>
#include <linux/mfd/wm8350/core.h>
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 DEFINE_MUTEX(wdt_mutex);
static struct {
unsigned int time; /* Seconds */
u16 val; /* To be set in WM8350_SYSTEM_CONTROL_2 */
} wm8350_wdt_cfgs[] = {
{ 1, 0x02 },
{ 2, 0x04 },
{ 4, 0x05 },
};
static int wm8350_wdt_set_timeout(struct watchdog_device *wdt_dev,
unsigned int timeout)
{
struct wm8350 *wm8350 = watchdog_get_drvdata(wdt_dev);
int ret, i;
u16 reg;
for (i = 0; i < ARRAY_SIZE(wm8350_wdt_cfgs); i++)
if (wm8350_wdt_cfgs[i].time == timeout)
break;
if (i == ARRAY_SIZE(wm8350_wdt_cfgs))
return -EINVAL;
mutex_lock(&wdt_mutex);
wm8350_reg_unlock(wm8350);
reg = wm8350_reg_read(wm8350, WM8350_SYSTEM_CONTROL_2);
reg &= ~WM8350_WDOG_TO_MASK;
reg |= wm8350_wdt_cfgs[i].val;
ret = wm8350_reg_write(wm8350, WM8350_SYSTEM_CONTROL_2, reg);
wm8350_reg_lock(wm8350);
mutex_unlock(&wdt_mutex);
wdt_dev->timeout = timeout;
return ret;
}
static int wm8350_wdt_start(struct watchdog_device *wdt_dev)
{
struct wm8350 *wm8350 = watchdog_get_drvdata(wdt_dev);
int ret;
u16 reg;
mutex_lock(&wdt_mutex);
wm8350_reg_unlock(wm8350);
reg = wm8350_reg_read(wm8350, WM8350_SYSTEM_CONTROL_2);
reg &= ~WM8350_WDOG_MODE_MASK;
reg |= 0x20;
ret = wm8350_reg_write(wm8350, WM8350_SYSTEM_CONTROL_2, reg);
wm8350_reg_lock(wm8350);
mutex_unlock(&wdt_mutex);
return ret;
}
static int wm8350_wdt_stop(struct watchdog_device *wdt_dev)
{
struct wm8350 *wm8350 = watchdog_get_drvdata(wdt_dev);
int ret;
u16 reg;
mutex_lock(&wdt_mutex);
wm8350_reg_unlock(wm8350);
reg = wm8350_reg_read(wm8350, WM8350_SYSTEM_CONTROL_2);
reg &= ~WM8350_WDOG_MODE_MASK;
ret = wm8350_reg_write(wm8350, WM8350_SYSTEM_CONTROL_2, reg);
wm8350_reg_lock(wm8350);
mutex_unlock(&wdt_mutex);
return ret;
}
static int wm8350_wdt_ping(struct watchdog_device *wdt_dev)
{
struct wm8350 *wm8350 = watchdog_get_drvdata(wdt_dev);
int ret;
u16 reg;
mutex_lock(&wdt_mutex);
reg = wm8350_reg_read(wm8350, WM8350_SYSTEM_CONTROL_2);
ret = wm8350_reg_write(wm8350, WM8350_SYSTEM_CONTROL_2, reg);
mutex_unlock(&wdt_mutex);
return ret;
}
static const struct watchdog_info wm8350_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
.identity = "WM8350 Watchdog",
};
static const struct watchdog_ops wm8350_wdt_ops = {
.owner = THIS_MODULE,
.start = wm8350_wdt_start,
.stop = wm8350_wdt_stop,
.ping = wm8350_wdt_ping,
.set_timeout = wm8350_wdt_set_timeout,
};
static struct watchdog_device wm8350_wdt = {
.info = &wm8350_wdt_info,
.ops = &wm8350_wdt_ops,
.timeout = 4,
.min_timeout = 1,
.max_timeout = 4,
};
static int wm8350_wdt_probe(struct platform_device *pdev)
{
struct wm8350 *wm8350 = platform_get_drvdata(pdev);
if (!wm8350) {
pr_err("No driver data supplied\n");
return -ENODEV;
}
watchdog_set_nowayout(&wm8350_wdt, nowayout);
watchdog_set_drvdata(&wm8350_wdt, wm8350);
wm8350_wdt.parent = &pdev->dev;
/* Default to 4s timeout */
wm8350_wdt_set_timeout(&wm8350_wdt, 4);
return watchdog_register_device(&wm8350_wdt);
}
static int wm8350_wdt_remove(struct platform_device *pdev)
{
watchdog_unregister_device(&wm8350_wdt);
return 0;
}
static struct platform_driver wm8350_wdt_driver = {
.probe = wm8350_wdt_probe,
.remove = wm8350_wdt_remove,
.driver = {
.name = "wm8350-wdt",
},
};
module_platform_driver(wm8350_wdt_driver);
MODULE_AUTHOR("Mark Brown");
MODULE_DESCRIPTION("WM8350 Watchdog");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:wm8350-wdt");