linux/drivers/watchdog/ux500_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

170 lines
4.0 KiB
C

/*
* Copyright (C) ST-Ericsson SA 2011-2013
*
* License Terms: GNU General Public License v2
*
* Author: Mathieu Poirier <mathieu.poirier@linaro.org> for ST-Ericsson
* Author: Jonas Aaberg <jonas.aberg@stericsson.com> for ST-Ericsson
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/moduleparam.h>
#include <linux/err.h>
#include <linux/uaccess.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
#include <linux/platform_data/ux500_wdt.h>
#include <linux/mfd/dbx500-prcmu.h>
#define WATCHDOG_TIMEOUT 600 /* 10 minutes */
#define WATCHDOG_MIN 0
#define WATCHDOG_MAX28 268435 /* 28 bit resolution in ms == 268435.455 s */
#define WATCHDOG_MAX32 4294967 /* 32 bit resolution in ms == 4294967.295 s */
static unsigned int timeout = WATCHDOG_TIMEOUT;
module_param(timeout, uint, 0);
MODULE_PARM_DESC(timeout,
"Watchdog timeout in seconds. default="
__MODULE_STRING(WATCHDOG_TIMEOUT) ".");
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 ux500_wdt_start(struct watchdog_device *wdd)
{
return prcmu_enable_a9wdog(PRCMU_WDOG_ALL);
}
static int ux500_wdt_stop(struct watchdog_device *wdd)
{
return prcmu_disable_a9wdog(PRCMU_WDOG_ALL);
}
static int ux500_wdt_keepalive(struct watchdog_device *wdd)
{
return prcmu_kick_a9wdog(PRCMU_WDOG_ALL);
}
static int ux500_wdt_set_timeout(struct watchdog_device *wdd,
unsigned int timeout)
{
ux500_wdt_stop(wdd);
prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);
ux500_wdt_start(wdd);
return 0;
}
static const struct watchdog_info ux500_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
.identity = "Ux500 WDT",
.firmware_version = 1,
};
static const struct watchdog_ops ux500_wdt_ops = {
.owner = THIS_MODULE,
.start = ux500_wdt_start,
.stop = ux500_wdt_stop,
.ping = ux500_wdt_keepalive,
.set_timeout = ux500_wdt_set_timeout,
};
static struct watchdog_device ux500_wdt = {
.info = &ux500_wdt_info,
.ops = &ux500_wdt_ops,
.min_timeout = WATCHDOG_MIN,
.max_timeout = WATCHDOG_MAX32,
};
static int ux500_wdt_probe(struct platform_device *pdev)
{
int ret;
struct ux500_wdt_data *pdata = dev_get_platdata(&pdev->dev);
if (pdata) {
if (pdata->timeout > 0)
timeout = pdata->timeout;
if (pdata->has_28_bits_resolution)
ux500_wdt.max_timeout = WATCHDOG_MAX28;
}
ux500_wdt.parent = &pdev->dev;
watchdog_set_nowayout(&ux500_wdt, nowayout);
/* disable auto off on sleep */
prcmu_config_a9wdog(PRCMU_WDOG_CPU1, false);
/* set HW initial value */
prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);
ret = watchdog_register_device(&ux500_wdt);
if (ret)
return ret;
dev_info(&pdev->dev, "initialized\n");
return 0;
}
static int ux500_wdt_remove(struct platform_device *dev)
{
watchdog_unregister_device(&ux500_wdt);
return 0;
}
#ifdef CONFIG_PM
static int ux500_wdt_suspend(struct platform_device *pdev,
pm_message_t state)
{
if (watchdog_active(&ux500_wdt)) {
ux500_wdt_stop(&ux500_wdt);
prcmu_config_a9wdog(PRCMU_WDOG_CPU1, true);
prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);
ux500_wdt_start(&ux500_wdt);
}
return 0;
}
static int ux500_wdt_resume(struct platform_device *pdev)
{
if (watchdog_active(&ux500_wdt)) {
ux500_wdt_stop(&ux500_wdt);
prcmu_config_a9wdog(PRCMU_WDOG_CPU1, false);
prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);
ux500_wdt_start(&ux500_wdt);
}
return 0;
}
#else
#define ux500_wdt_suspend NULL
#define ux500_wdt_resume NULL
#endif
static struct platform_driver ux500_wdt_driver = {
.probe = ux500_wdt_probe,
.remove = ux500_wdt_remove,
.suspend = ux500_wdt_suspend,
.resume = ux500_wdt_resume,
.driver = {
.name = "ux500_wdt",
},
};
module_platform_driver(ux500_wdt_driver);
MODULE_AUTHOR("Jonas Aaberg <jonas.aberg@stericsson.com>");
MODULE_DESCRIPTION("Ux500 Watchdog Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:ux500_wdt");