linux/drivers/watchdog/da9063_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

223 lines
5.7 KiB
C

/*
* Watchdog driver for DA9063 PMICs.
*
* Copyright(c) 2012 Dialog Semiconductor Ltd.
*
* Author: Mariusz Wojtasik <mariusz.wojtasik@diasemi.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.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
#include <linux/uaccess.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/mfd/da9063/registers.h>
#include <linux/mfd/da9063/core.h>
#include <linux/reboot.h>
#include <linux/regmap.h>
/*
* Watchdog selector to timeout in seconds.
* 0: WDT disabled;
* others: timeout = 2048 ms * 2^(TWDSCALE-1).
*/
static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
#define DA9063_TWDSCALE_DISABLE 0
#define DA9063_TWDSCALE_MIN 1
#define DA9063_TWDSCALE_MAX (ARRAY_SIZE(wdt_timeout) - 1)
#define DA9063_WDT_MIN_TIMEOUT wdt_timeout[DA9063_TWDSCALE_MIN]
#define DA9063_WDT_MAX_TIMEOUT wdt_timeout[DA9063_TWDSCALE_MAX]
#define DA9063_WDG_TIMEOUT wdt_timeout[3]
struct da9063_watchdog {
struct da9063 *da9063;
struct watchdog_device wdtdev;
struct notifier_block restart_handler;
};
static unsigned int da9063_wdt_timeout_to_sel(unsigned int secs)
{
unsigned int i;
for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) {
if (wdt_timeout[i] >= secs)
return i;
}
return DA9063_TWDSCALE_MAX;
}
static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int regval)
{
return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
DA9063_TWDSCALE_MASK, regval);
}
static int da9063_wdt_start(struct watchdog_device *wdd)
{
struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
unsigned int selector;
int ret;
selector = da9063_wdt_timeout_to_sel(wdt->wdtdev.timeout);
ret = _da9063_wdt_set_timeout(wdt->da9063, selector);
if (ret)
dev_err(wdt->da9063->dev, "Watchdog failed to start (err = %d)\n",
ret);
return ret;
}
static int da9063_wdt_stop(struct watchdog_device *wdd)
{
struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
int ret;
ret = regmap_update_bits(wdt->da9063->regmap, DA9063_REG_CONTROL_D,
DA9063_TWDSCALE_MASK, DA9063_TWDSCALE_DISABLE);
if (ret)
dev_alert(wdt->da9063->dev, "Watchdog failed to stop (err = %d)\n",
ret);
return ret;
}
static int da9063_wdt_ping(struct watchdog_device *wdd)
{
struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
int ret;
ret = regmap_write(wdt->da9063->regmap, DA9063_REG_CONTROL_F,
DA9063_WATCHDOG);
if (ret)
dev_alert(wdt->da9063->dev, "Failed to ping the watchdog (err = %d)\n",
ret);
return ret;
}
static int da9063_wdt_set_timeout(struct watchdog_device *wdd,
unsigned int timeout)
{
struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
unsigned int selector;
int ret;
selector = da9063_wdt_timeout_to_sel(timeout);
ret = _da9063_wdt_set_timeout(wdt->da9063, selector);
if (ret)
dev_err(wdt->da9063->dev, "Failed to set watchdog timeout (err = %d)\n",
ret);
else
wdd->timeout = wdt_timeout[selector];
return ret;
}
static int da9063_wdt_restart_handler(struct notifier_block *this,
unsigned long mode, void *cmd)
{
struct da9063_watchdog *wdt = container_of(this,
struct da9063_watchdog,
restart_handler);
int ret;
ret = regmap_write(wdt->da9063->regmap, DA9063_REG_CONTROL_F,
DA9063_SHUTDOWN);
if (ret)
dev_alert(wdt->da9063->dev, "Failed to shutdown (err = %d)\n",
ret);
return NOTIFY_DONE;
}
static const struct watchdog_info da9063_watchdog_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
.identity = "DA9063 Watchdog",
};
static const struct watchdog_ops da9063_watchdog_ops = {
.owner = THIS_MODULE,
.start = da9063_wdt_start,
.stop = da9063_wdt_stop,
.ping = da9063_wdt_ping,
.set_timeout = da9063_wdt_set_timeout,
};
static int da9063_wdt_probe(struct platform_device *pdev)
{
int ret;
struct da9063 *da9063;
struct da9063_watchdog *wdt;
if (!pdev->dev.parent)
return -EINVAL;
da9063 = dev_get_drvdata(pdev->dev.parent);
if (!da9063)
return -EINVAL;
wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
if (!wdt)
return -ENOMEM;
wdt->da9063 = da9063;
wdt->wdtdev.info = &da9063_watchdog_info;
wdt->wdtdev.ops = &da9063_watchdog_ops;
wdt->wdtdev.min_timeout = DA9063_WDT_MIN_TIMEOUT;
wdt->wdtdev.max_timeout = DA9063_WDT_MAX_TIMEOUT;
wdt->wdtdev.timeout = DA9063_WDG_TIMEOUT;
wdt->wdtdev.parent = &pdev->dev;
wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS;
watchdog_set_drvdata(&wdt->wdtdev, wdt);
dev_set_drvdata(&pdev->dev, wdt);
ret = watchdog_register_device(&wdt->wdtdev);
if (ret)
return ret;
wdt->restart_handler.notifier_call = da9063_wdt_restart_handler;
wdt->restart_handler.priority = 128;
ret = register_restart_handler(&wdt->restart_handler);
if (ret)
dev_err(wdt->da9063->dev,
"Failed to register restart handler (err = %d)\n", ret);
return 0;
}
static int da9063_wdt_remove(struct platform_device *pdev)
{
struct da9063_watchdog *wdt = dev_get_drvdata(&pdev->dev);
unregister_restart_handler(&wdt->restart_handler);
watchdog_unregister_device(&wdt->wdtdev);
return 0;
}
static struct platform_driver da9063_wdt_driver = {
.probe = da9063_wdt_probe,
.remove = da9063_wdt_remove,
.driver = {
.name = DA9063_DRVNAME_WATCHDOG,
},
};
module_platform_driver(da9063_wdt_driver);
MODULE_AUTHOR("Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>");
MODULE_DESCRIPTION("Watchdog driver for Dialog DA9063");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DA9063_DRVNAME_WATCHDOG);