249 строки
6.2 KiB
C
249 строки
6.2 KiB
C
/*
|
|
* Watchdog device driver for DA9062 and DA9061 PMICs
|
|
* Copyright (C) 2015 Dialog Semiconductor Ltd.
|
|
*
|
|
* 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.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*/
|
|
|
|
#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/jiffies.h>
|
|
#include <linux/mfd/da9062/registers.h>
|
|
#include <linux/mfd/da9062/core.h>
|
|
#include <linux/regmap.h>
|
|
#include <linux/of.h>
|
|
|
|
static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
|
|
#define DA9062_TWDSCALE_DISABLE 0
|
|
#define DA9062_TWDSCALE_MIN 1
|
|
#define DA9062_TWDSCALE_MAX (ARRAY_SIZE(wdt_timeout) - 1)
|
|
#define DA9062_WDT_MIN_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MIN]
|
|
#define DA9062_WDT_MAX_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MAX]
|
|
#define DA9062_WDG_DEFAULT_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MAX-1]
|
|
#define DA9062_RESET_PROTECTION_MS 300
|
|
|
|
struct da9062_watchdog {
|
|
struct da9062 *hw;
|
|
struct watchdog_device wdtdev;
|
|
unsigned long j_time_stamp;
|
|
};
|
|
|
|
static void da9062_set_window_start(struct da9062_watchdog *wdt)
|
|
{
|
|
wdt->j_time_stamp = jiffies;
|
|
}
|
|
|
|
static void da9062_apply_window_protection(struct da9062_watchdog *wdt)
|
|
{
|
|
unsigned long delay = msecs_to_jiffies(DA9062_RESET_PROTECTION_MS);
|
|
unsigned long timeout = wdt->j_time_stamp + delay;
|
|
unsigned long now = jiffies;
|
|
unsigned int diff_ms;
|
|
|
|
/* if time-limit has not elapsed then wait for remainder */
|
|
if (time_before(now, timeout)) {
|
|
diff_ms = jiffies_to_msecs(timeout-now);
|
|
dev_dbg(wdt->hw->dev,
|
|
"Kicked too quickly. Delaying %u msecs\n", diff_ms);
|
|
msleep(diff_ms);
|
|
}
|
|
}
|
|
|
|
static unsigned int da9062_wdt_timeout_to_sel(unsigned int secs)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = DA9062_TWDSCALE_MIN; i <= DA9062_TWDSCALE_MAX; i++) {
|
|
if (wdt_timeout[i] >= secs)
|
|
return i;
|
|
}
|
|
|
|
return DA9062_TWDSCALE_MAX;
|
|
}
|
|
|
|
static int da9062_reset_watchdog_timer(struct da9062_watchdog *wdt)
|
|
{
|
|
int ret;
|
|
|
|
da9062_apply_window_protection(wdt);
|
|
|
|
ret = regmap_update_bits(wdt->hw->regmap,
|
|
DA9062AA_CONTROL_F,
|
|
DA9062AA_WATCHDOG_MASK,
|
|
DA9062AA_WATCHDOG_MASK);
|
|
|
|
da9062_set_window_start(wdt);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int da9062_wdt_update_timeout_register(struct da9062_watchdog *wdt,
|
|
unsigned int regval)
|
|
{
|
|
struct da9062 *chip = wdt->hw;
|
|
int ret;
|
|
|
|
ret = da9062_reset_watchdog_timer(wdt);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return regmap_update_bits(chip->regmap,
|
|
DA9062AA_CONTROL_D,
|
|
DA9062AA_TWDSCALE_MASK,
|
|
regval);
|
|
}
|
|
|
|
static int da9062_wdt_start(struct watchdog_device *wdd)
|
|
{
|
|
struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
|
|
unsigned int selector;
|
|
int ret;
|
|
|
|
selector = da9062_wdt_timeout_to_sel(wdt->wdtdev.timeout);
|
|
ret = da9062_wdt_update_timeout_register(wdt, selector);
|
|
if (ret)
|
|
dev_err(wdt->hw->dev, "Watchdog failed to start (err = %d)\n",
|
|
ret);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int da9062_wdt_stop(struct watchdog_device *wdd)
|
|
{
|
|
struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
|
|
int ret;
|
|
|
|
ret = da9062_reset_watchdog_timer(wdt);
|
|
if (ret) {
|
|
dev_err(wdt->hw->dev, "Failed to ping the watchdog (err = %d)\n",
|
|
ret);
|
|
return ret;
|
|
}
|
|
|
|
ret = regmap_update_bits(wdt->hw->regmap,
|
|
DA9062AA_CONTROL_D,
|
|
DA9062AA_TWDSCALE_MASK,
|
|
DA9062_TWDSCALE_DISABLE);
|
|
if (ret)
|
|
dev_err(wdt->hw->dev, "Watchdog failed to stop (err = %d)\n",
|
|
ret);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int da9062_wdt_ping(struct watchdog_device *wdd)
|
|
{
|
|
struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
|
|
int ret;
|
|
|
|
ret = da9062_reset_watchdog_timer(wdt);
|
|
if (ret)
|
|
dev_err(wdt->hw->dev, "Failed to ping the watchdog (err = %d)\n",
|
|
ret);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int da9062_wdt_set_timeout(struct watchdog_device *wdd,
|
|
unsigned int timeout)
|
|
{
|
|
struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
|
|
unsigned int selector;
|
|
int ret;
|
|
|
|
selector = da9062_wdt_timeout_to_sel(timeout);
|
|
ret = da9062_wdt_update_timeout_register(wdt, selector);
|
|
if (ret)
|
|
dev_err(wdt->hw->dev, "Failed to set watchdog timeout (err = %d)\n",
|
|
ret);
|
|
else
|
|
wdd->timeout = wdt_timeout[selector];
|
|
|
|
return ret;
|
|
}
|
|
|
|
static const struct watchdog_info da9062_watchdog_info = {
|
|
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
|
|
.identity = "DA9062 WDT",
|
|
};
|
|
|
|
static const struct watchdog_ops da9062_watchdog_ops = {
|
|
.owner = THIS_MODULE,
|
|
.start = da9062_wdt_start,
|
|
.stop = da9062_wdt_stop,
|
|
.ping = da9062_wdt_ping,
|
|
.set_timeout = da9062_wdt_set_timeout,
|
|
};
|
|
|
|
static const struct of_device_id da9062_compatible_id_table[] = {
|
|
{ .compatible = "dlg,da9062-watchdog", },
|
|
{ },
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(of, da9062_compatible_id_table);
|
|
|
|
static int da9062_wdt_probe(struct platform_device *pdev)
|
|
{
|
|
int ret;
|
|
struct da9062 *chip;
|
|
struct da9062_watchdog *wdt;
|
|
|
|
chip = dev_get_drvdata(pdev->dev.parent);
|
|
if (!chip)
|
|
return -EINVAL;
|
|
|
|
wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
|
|
if (!wdt)
|
|
return -ENOMEM;
|
|
|
|
wdt->hw = chip;
|
|
|
|
wdt->wdtdev.info = &da9062_watchdog_info;
|
|
wdt->wdtdev.ops = &da9062_watchdog_ops;
|
|
wdt->wdtdev.min_timeout = DA9062_WDT_MIN_TIMEOUT;
|
|
wdt->wdtdev.max_timeout = DA9062_WDT_MAX_TIMEOUT;
|
|
wdt->wdtdev.timeout = DA9062_WDG_DEFAULT_TIMEOUT;
|
|
wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS;
|
|
wdt->wdtdev.parent = &pdev->dev;
|
|
|
|
watchdog_set_drvdata(&wdt->wdtdev, wdt);
|
|
|
|
ret = devm_watchdog_register_device(&pdev->dev, &wdt->wdtdev);
|
|
if (ret < 0) {
|
|
dev_err(wdt->hw->dev,
|
|
"watchdog registration failed (%d)\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
da9062_set_window_start(wdt);
|
|
|
|
return da9062_wdt_ping(&wdt->wdtdev);
|
|
}
|
|
|
|
static struct platform_driver da9062_wdt_driver = {
|
|
.probe = da9062_wdt_probe,
|
|
.driver = {
|
|
.name = "da9062-watchdog",
|
|
.of_match_table = da9062_compatible_id_table,
|
|
},
|
|
};
|
|
module_platform_driver(da9062_wdt_driver);
|
|
|
|
MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
|
|
MODULE_DESCRIPTION("WDT device driver for Dialog DA9062 and DA9061");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("platform:da9062-watchdog");
|