mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-26 09:55:12 +07:00
28804c2c8f
The STPMIC1 PMIC embeds a watchdog which is disabled by default. As soon as the watchdog is started, it must be refreshed periodically otherwise the PMIC goes off. Signed-off-by: Pascal Paillet <p.paillet@st.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Lee Jones <lee.jones@linaro.org>
140 lines
3.5 KiB
C
140 lines
3.5 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
// Copyright (C) STMicroelectronics 2018
|
|
// Author: Pascal Paillet <p.paillet@st.com> for STMicroelectronics.
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/mfd/stpmic1.h>
|
|
#include <linux/module.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/of.h>
|
|
#include <linux/regmap.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/watchdog.h>
|
|
|
|
/* WATCHDOG CONTROL REGISTER bit */
|
|
#define WDT_START BIT(0)
|
|
#define WDT_PING BIT(1)
|
|
#define WDT_START_MASK BIT(0)
|
|
#define WDT_PING_MASK BIT(1)
|
|
#define WDT_STOP 0
|
|
|
|
#define PMIC_WDT_MIN_TIMEOUT 1
|
|
#define PMIC_WDT_MAX_TIMEOUT 256
|
|
#define PMIC_WDT_DEFAULT_TIMEOUT 30
|
|
|
|
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) ")");
|
|
|
|
struct stpmic1_wdt {
|
|
struct stpmic1 *pmic;
|
|
struct watchdog_device wdtdev;
|
|
};
|
|
|
|
static int pmic_wdt_start(struct watchdog_device *wdd)
|
|
{
|
|
struct stpmic1_wdt *wdt = watchdog_get_drvdata(wdd);
|
|
|
|
return regmap_update_bits(wdt->pmic->regmap,
|
|
WCHDG_CR, WDT_START_MASK, WDT_START);
|
|
}
|
|
|
|
static int pmic_wdt_stop(struct watchdog_device *wdd)
|
|
{
|
|
struct stpmic1_wdt *wdt = watchdog_get_drvdata(wdd);
|
|
|
|
return regmap_update_bits(wdt->pmic->regmap,
|
|
WCHDG_CR, WDT_START_MASK, WDT_STOP);
|
|
}
|
|
|
|
static int pmic_wdt_ping(struct watchdog_device *wdd)
|
|
{
|
|
struct stpmic1_wdt *wdt = watchdog_get_drvdata(wdd);
|
|
|
|
return regmap_update_bits(wdt->pmic->regmap,
|
|
WCHDG_CR, WDT_PING_MASK, WDT_PING);
|
|
}
|
|
|
|
static int pmic_wdt_set_timeout(struct watchdog_device *wdd,
|
|
unsigned int timeout)
|
|
{
|
|
struct stpmic1_wdt *wdt = watchdog_get_drvdata(wdd);
|
|
|
|
wdd->timeout = timeout;
|
|
/* timeout is equal to register value + 1 */
|
|
return regmap_write(wdt->pmic->regmap, WCHDG_TIMER_CR, timeout - 1);
|
|
}
|
|
|
|
static const struct watchdog_info pmic_watchdog_info = {
|
|
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
|
|
.identity = "STPMIC1 PMIC Watchdog",
|
|
};
|
|
|
|
static const struct watchdog_ops pmic_watchdog_ops = {
|
|
.owner = THIS_MODULE,
|
|
.start = pmic_wdt_start,
|
|
.stop = pmic_wdt_stop,
|
|
.ping = pmic_wdt_ping,
|
|
.set_timeout = pmic_wdt_set_timeout,
|
|
};
|
|
|
|
static int pmic_wdt_probe(struct platform_device *pdev)
|
|
{
|
|
int ret;
|
|
struct stpmic1 *pmic;
|
|
struct stpmic1_wdt *wdt;
|
|
|
|
if (!pdev->dev.parent)
|
|
return -EINVAL;
|
|
|
|
pmic = dev_get_drvdata(pdev->dev.parent);
|
|
if (!pmic)
|
|
return -EINVAL;
|
|
|
|
wdt = devm_kzalloc(&pdev->dev, sizeof(struct stpmic1_wdt), GFP_KERNEL);
|
|
if (!wdt)
|
|
return -ENOMEM;
|
|
|
|
wdt->pmic = pmic;
|
|
|
|
wdt->wdtdev.info = &pmic_watchdog_info;
|
|
wdt->wdtdev.ops = &pmic_watchdog_ops;
|
|
wdt->wdtdev.min_timeout = PMIC_WDT_MIN_TIMEOUT;
|
|
wdt->wdtdev.max_timeout = PMIC_WDT_MAX_TIMEOUT;
|
|
wdt->wdtdev.parent = &pdev->dev;
|
|
|
|
wdt->wdtdev.timeout = PMIC_WDT_DEFAULT_TIMEOUT;
|
|
watchdog_init_timeout(&wdt->wdtdev, 0, &pdev->dev);
|
|
|
|
watchdog_set_nowayout(&wdt->wdtdev, nowayout);
|
|
watchdog_set_drvdata(&wdt->wdtdev, wdt);
|
|
|
|
ret = devm_watchdog_register_device(&pdev->dev, &wdt->wdtdev);
|
|
if (ret)
|
|
return ret;
|
|
|
|
dev_dbg(wdt->pmic->dev, "PMIC Watchdog driver probed\n");
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id of_pmic_wdt_match[] = {
|
|
{ .compatible = "st,stpmic1-wdt" },
|
|
{ },
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(of, of_pmic_wdt_match);
|
|
|
|
static struct platform_driver stpmic1_wdt_driver = {
|
|
.probe = pmic_wdt_probe,
|
|
.driver = {
|
|
.name = "stpmic1-wdt",
|
|
.of_match_table = of_pmic_wdt_match,
|
|
},
|
|
};
|
|
module_platform_driver(stpmic1_wdt_driver);
|
|
|
|
MODULE_DESCRIPTION("Watchdog driver for STPMIC1 device");
|
|
MODULE_AUTHOR("Pascal Paillet <p.paillet@st.com>");
|
|
MODULE_LICENSE("GPL v2");
|