blob: e532539afa83f365e1649ac5add519134d0f1df5 [file] [log] [blame]
/*
* as3722_wdt.c -- AS3722 Watchdog Timer.
*
* Watchdog timer for AS3722 PMIC.
*
* Copyright (c) 2013, NVIDIA Corporation. All rights reserved.
*
* Author: Bibek Basu <bbasu@nvidia.com>
* based on Palmas_wdt driver (c) Laxman Dewangan , 2013
*
* 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 version 2.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
* whether express or implied; 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/device.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mfd/as3722.h>
#include <linux/mfd/as3722-plat.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/slab.h>
#include <linux/watchdog.h>
static bool nowayout = WATCHDOG_NOWAYOUT;
struct as3722_wdt {
struct watchdog_device wdt_dev;
struct device *dev;
struct as3722 *as3722;
int timeout;
int irq;
};
static irqreturn_t as3722_wdt_irq(int irq, void *data)
{
struct as3722_wdt *wdt = data;
int ret;
ret = as3722_update_bits(wdt->as3722,
AS3722_WATCHDOG_SOFTWARE_SIGNAL_REG,
AS3722_WATCHDOG_SW_SIG, AS3722_WATCHDOG_SW_SIG);
if (ret < 0)
dev_err(wdt->dev, "WATCHDOG kick failed: %d\n", ret);
dev_info(wdt->dev, "WDT interrupt occur\n");
return IRQ_HANDLED;
}
static int as3722_wdt_start(struct watchdog_device *wdt_dev)
{
struct as3722_wdt *wdt = watchdog_get_drvdata(wdt_dev);
int ret;
ret = as3722_update_bits(wdt->as3722, AS3722_WATCHDOG_CONTROL_REG,
AS3722_WATCHDOG_ON, AS3722_WATCHDOG_ON);
if (ret < 0) {
dev_err(wdt->dev, "WATCHDOG update failed: %d\n", ret);
return ret;
}
return 0;
}
static int as3722_wdt_stop(struct watchdog_device *wdt_dev)
{
struct as3722_wdt *wdt = watchdog_get_drvdata(wdt_dev);
int ret;
ret = as3722_update_bits(wdt->as3722, AS3722_WATCHDOG_CONTROL_REG,
AS3722_WATCHDOG_ON, 0);
if (ret < 0) {
dev_err(wdt->dev, "WATCHDOG update failed: %d\n", ret);
return ret;
}
return 0;
}
static int as3722_wdt_set_timeout(struct watchdog_device *wdt_dev,
unsigned int timeout)
{
struct as3722_wdt *wdt = watchdog_get_drvdata(wdt_dev);
int ret;
unsigned int val = timeout - 1;
ret = as3722_update_bits(wdt->as3722, AS3722_WATCHDOG_TIMER_REG,
AS3722_WATCHDOG_TIMER_MAX, val);
if (ret < 0) {
dev_err(wdt->dev, "WATCHDOG update failed: %d\n", ret);
return ret;
}
wdt->timeout = timeout;
return 0;
}
static const struct watchdog_info as3722_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
.identity = "AS3722 Watchdog",
};
static const struct watchdog_ops as3722_wdt_ops = {
.owner = THIS_MODULE,
.start = as3722_wdt_start,
.stop = as3722_wdt_stop,
.set_timeout = as3722_wdt_set_timeout,
};
static int as3722_wdt_probe(struct platform_device *pdev)
{
struct as3722 *as3722 = dev_get_drvdata(pdev->dev.parent);
struct as3722_platform_data *pdata = as3722->dev->platform_data;
struct as3722_wdt *wdt;
struct watchdog_device *wdt_dev;
int ret;
wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
if (!wdt)
return -ENOMEM;
wdt->dev = &pdev->dev;
wdt->as3722 = as3722;
wdt->irq = as3722_irq_get_virq(wdt->as3722, AS3722_IRQ_WATCHDOG);
wdt_dev = &wdt->wdt_dev;
wdt_dev->info = &as3722_wdt_info;
wdt_dev->ops = &as3722_wdt_ops;
wdt_dev->timeout = 128;
wdt_dev->min_timeout = 8;
wdt_dev->max_timeout = 128;
watchdog_set_nowayout(wdt_dev, nowayout);
watchdog_set_drvdata(wdt_dev, wdt);
platform_set_drvdata(pdev, wdt);
ret = request_threaded_irq(wdt->irq, NULL, as3722_wdt_irq,
IRQF_ONESHOT | IRQF_EARLY_RESUME,
dev_name(&pdev->dev), wdt);
if (ret < 0) {
dev_err(&pdev->dev, "request IRQ:%d failed, err = %d\n",
wdt->irq, ret);
return ret;
}
ret = watchdog_register_device(wdt_dev);
if (ret < 0) {
dev_err(&pdev->dev, "watchdog registration failed: %d\n", ret);
return ret;
}
/* set mode */
if (pdata && (pdata->watchdog_timer_mode >= 0)) {
ret = as3722_update_bits(wdt->as3722,
AS3722_WATCHDOG_CONTROL_REG,
AS3722_WATCHDOG_MODE_MASK, pdata->watchdog_timer_mode);
if (ret < 0) {
dev_err(wdt->dev, "WATCHDOG update mode failed: %d\n",
ret);
goto scrub;
}
}
/* configure timer */
if (pdata && (pdata->watchdog_timer_initial_period > 0)) {
ret = as3722_wdt_set_timeout(wdt_dev,
pdata->watchdog_timer_initial_period);
if (ret < 0) {
dev_err(wdt->dev, "wdt set timeout failed: %d\n", ret);
goto scrub;
}
ret = as3722_wdt_start(wdt_dev);
if (ret < 0) {
dev_err(wdt->dev,
"wdt start failed: %d\n", ret);
goto scrub;
}
}
device_set_wakeup_capable(&pdev->dev, 1);
return 0;
scrub:
free_irq(wdt->irq, wdt);
watchdog_unregister_device(&wdt->wdt_dev);
return ret;
}
static int as3722_wdt_remove(struct platform_device *pdev)
{
struct as3722_wdt *wdt = platform_get_drvdata(pdev);
as3722_wdt_stop(&wdt->wdt_dev);
watchdog_unregister_device(&wdt->wdt_dev);
free_irq(wdt->irq, wdt);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int as3722_wdt_suspend(struct device *dev)
{
struct as3722_wdt *wdt = dev_get_drvdata(dev);
int ret;
if (device_may_wakeup(dev)) {
enable_irq_wake(wdt->irq);
} else if (wdt->timeout > 0) {
ret = as3722_wdt_stop(&wdt->wdt_dev);
if (ret < 0)
dev_err(wdt->dev, "wdt stop failed: %d\n", ret);
}
return 0;
}
static int as3722_wdt_resume(struct device *dev)
{
struct as3722_wdt *wdt = dev_get_drvdata(dev);
int ret;
if (device_may_wakeup(dev)) {
disable_irq_wake(wdt->irq);
} else if (wdt->timeout > 0) {
ret = as3722_wdt_start(&wdt->wdt_dev);
if (ret < 0)
dev_err(wdt->dev, "wdt start failed: %d\n", ret);
}
return 0;
}
#endif
static const struct dev_pm_ops as3722_wdt_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(as3722_wdt_suspend, as3722_wdt_resume)
};
static struct platform_driver as3722_wdt_driver = {
.driver = {
.name = "as3722-wdt",
.owner = THIS_MODULE,
.pm = &as3722_wdt_pm_ops,
},
.probe = as3722_wdt_probe,
.remove = as3722_wdt_remove,
};
static int __init as3722_wdt_init(void)
{
return platform_driver_register(&as3722_wdt_driver);
}
subsys_initcall(as3722_wdt_init);
static void __exit as3722_wdt_exit(void)
{
platform_driver_unregister(&as3722_wdt_driver);
}
module_exit(as3722_wdt_exit);
MODULE_ALIAS("platform:as3722-wdt");
MODULE_DESCRIPTION("AMS AS3722 watchdog timer driver");
MODULE_AUTHOR("Bibek Basu <bbasu@nvidia.com>");
MODULE_LICENSE("GPL v2");