Commit bbc88a0e authored by Matti Vaittinen's avatar Matti Vaittinen Committed by Wim Van Sebroeck

watchdog: bd70528: Initial support for ROHM BD70528 watchdog block

Initial support for watchdog block included in ROHM BD70528
power management IC.

Configurations for low power states are still to be checked.
Signed-off-by: default avatarMatti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Acked-by: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarWim Van Sebroeck <wim@linux-watchdog.org>
parent e347afa5
...@@ -90,6 +90,18 @@ config SOFT_WATCHDOG_PRETIMEOUT ...@@ -90,6 +90,18 @@ config SOFT_WATCHDOG_PRETIMEOUT
watchdog. Be aware that governors might affect the watchdog because it watchdog. Be aware that governors might affect the watchdog because it
is purely software, e.g. the panic governor will stall it! is purely software, e.g. the panic governor will stall it!
config BD70528_WATCHDOG
tristate "ROHM BD70528 PMIC Watchdog"
depends on MFD_ROHM_BD70528
select WATCHDOG_CORE
help
Support for the watchdog in the ROHM BD70528 PMIC. Watchdog trigger
cause system reset.
Say Y here to include support for the ROHM BD70528 watchdog.
Alternatively say M to compile the driver as a module,
which will be called bd70528_wdt.
config DA9052_WATCHDOG config DA9052_WATCHDOG
tristate "Dialog DA9052 Watchdog" tristate "Dialog DA9052 Watchdog"
depends on PMIC_DA9052 || COMPILE_TEST depends on PMIC_DA9052 || COMPILE_TEST
......
...@@ -205,6 +205,7 @@ obj-$(CONFIG_WATCHDOG_SUN4V) += sun4v_wdt.o ...@@ -205,6 +205,7 @@ obj-$(CONFIG_WATCHDOG_SUN4V) += sun4v_wdt.o
obj-$(CONFIG_XEN_WDT) += xen_wdt.o obj-$(CONFIG_XEN_WDT) += xen_wdt.o
# Architecture Independent # Architecture Independent
obj-$(CONFIG_BD70528_WATCHDOG) += bd70528_wdt.o
obj-$(CONFIG_DA9052_WATCHDOG) += da9052_wdt.o obj-$(CONFIG_DA9052_WATCHDOG) += da9052_wdt.o
obj-$(CONFIG_DA9055_WATCHDOG) += da9055_wdt.o obj-$(CONFIG_DA9055_WATCHDOG) += da9055_wdt.o
obj-$(CONFIG_DA9062_WATCHDOG) += da9062_wdt.o obj-$(CONFIG_DA9062_WATCHDOG) += da9062_wdt.o
......
// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2018 ROHM Semiconductors
// ROHM BD70528MWV watchdog driver
#include <linux/bcd.h>
#include <linux/kernel.h>
#include <linux/mfd/rohm-bd70528.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/watchdog.h>
/*
* Max time we can set is 1 hour, 59 minutes and 59 seconds
* and Minimum time is 1 second
*/
#define WDT_MAX_MS ((2 * 60 * 60 - 1) * 1000)
#define WDT_MIN_MS 1000
#define DEFAULT_TIMEOUT 60
#define WD_CTRL_MAGIC1 0x55
#define WD_CTRL_MAGIC2 0xAA
struct wdtbd70528 {
struct device *dev;
struct regmap *regmap;
struct rohm_regmap_dev *mfd;
struct watchdog_device wdt;
};
/**
* bd70528_wdt_set - arm or disarm watchdog timer
*
* @data: device data for the PMIC instance we want to operate on
* @enable: new state of WDT. zero to disable, non zero to enable
* @old_state: previous state of WDT will be filled here
*
* Arm or disarm WDT on BD70528 PMIC. Expected to be called only by
* BD70528 RTC and BD70528 WDT drivers. The rtc_timer_lock must be taken
* by calling bd70528_wdt_lock before calling bd70528_wdt_set.
*/
int bd70528_wdt_set(struct rohm_regmap_dev *data, int enable, int *old_state)
{
int ret, i;
unsigned int tmp;
struct bd70528_data *bd70528 = container_of(data, struct bd70528_data,
chip);
u8 wd_ctrl_arr[3] = { WD_CTRL_MAGIC1, WD_CTRL_MAGIC2, 0 };
u8 *wd_ctrl = &wd_ctrl_arr[2];
ret = regmap_read(bd70528->chip.regmap, BD70528_REG_WDT_CTRL, &tmp);
if (ret)
return ret;
*wd_ctrl = (u8)tmp;
if (old_state) {
if (*wd_ctrl & BD70528_MASK_WDT_EN)
*old_state |= BD70528_WDT_STATE_BIT;
else
*old_state &= ~BD70528_WDT_STATE_BIT;
if ((!enable) == (!(*old_state & BD70528_WDT_STATE_BIT)))
return 0;
}
if (enable) {
if (*wd_ctrl & BD70528_MASK_WDT_EN)
return 0;
*wd_ctrl |= BD70528_MASK_WDT_EN;
} else {
if (*wd_ctrl & BD70528_MASK_WDT_EN)
*wd_ctrl &= ~BD70528_MASK_WDT_EN;
else
return 0;
}
for (i = 0; i < 3; i++) {
ret = regmap_write(bd70528->chip.regmap, BD70528_REG_WDT_CTRL,
wd_ctrl_arr[i]);
if (ret)
return ret;
}
ret = regmap_read(bd70528->chip.regmap, BD70528_REG_WDT_CTRL, &tmp);
if ((tmp & BD70528_MASK_WDT_EN) != (*wd_ctrl & BD70528_MASK_WDT_EN)) {
dev_err(bd70528->chip.dev,
"Watchdog ctrl mismatch (hw) 0x%x (set) 0x%x\n",
tmp, *wd_ctrl);
ret = -EIO;
}
return ret;
}
EXPORT_SYMBOL(bd70528_wdt_set);
/**
* bd70528_wdt_lock - take WDT lock
*
* @bd70528: device data for the PMIC instance we want to operate on
*
* Lock WDT for arming/disarming in order to avoid race condition caused
* by WDT state changes initiated by WDT and RTC drivers.
*/
void bd70528_wdt_lock(struct rohm_regmap_dev *data)
{
struct bd70528_data *bd70528 = container_of(data, struct bd70528_data,
chip);
mutex_lock(&bd70528->rtc_timer_lock);
}
EXPORT_SYMBOL(bd70528_wdt_lock);
/**
* bd70528_wdt_unlock - unlock WDT lock
*
* @bd70528: device data for the PMIC instance we want to operate on
*
* Unlock WDT lock which has previously been taken by call to
* bd70528_wdt_lock.
*/
void bd70528_wdt_unlock(struct rohm_regmap_dev *data)
{
struct bd70528_data *bd70528 = container_of(data, struct bd70528_data,
chip);
mutex_unlock(&bd70528->rtc_timer_lock);
}
EXPORT_SYMBOL(bd70528_wdt_unlock);
static int bd70528_wdt_set_locked(struct wdtbd70528 *w, int enable)
{
return bd70528_wdt_set(w->mfd, enable, NULL);
}
static int bd70528_wdt_change(struct wdtbd70528 *w, int enable)
{
int ret;
bd70528_wdt_lock(w->mfd);
ret = bd70528_wdt_set_locked(w, enable);
bd70528_wdt_unlock(w->mfd);
return ret;
}
static int bd70528_wdt_start(struct watchdog_device *wdt)
{
struct wdtbd70528 *w = watchdog_get_drvdata(wdt);
dev_dbg(w->dev, "WDT ping...\n");
return bd70528_wdt_change(w, 1);
}
static int bd70528_wdt_stop(struct watchdog_device *wdt)
{
struct wdtbd70528 *w = watchdog_get_drvdata(wdt);
dev_dbg(w->dev, "WDT stopping...\n");
return bd70528_wdt_change(w, 0);
}
static int bd70528_wdt_set_timeout(struct watchdog_device *wdt,
unsigned int timeout)
{
unsigned int hours;
unsigned int minutes;
unsigned int seconds;
int ret;
struct wdtbd70528 *w = watchdog_get_drvdata(wdt);
seconds = timeout;
hours = timeout / (60 * 60);
/* Maximum timeout is 1h 59m 59s => hours is 1 or 0 */
if (hours)
seconds -= (60 * 60);
minutes = seconds / 60;
seconds = seconds % 60;
bd70528_wdt_lock(w->mfd);
ret = bd70528_wdt_set_locked(w, 0);
if (ret)
goto out_unlock;
ret = regmap_update_bits(w->regmap, BD70528_REG_WDT_HOUR,
BD70528_MASK_WDT_HOUR, hours);
if (ret) {
dev_err(w->dev, "Failed to set WDT hours\n");
goto out_en_unlock;
}
ret = regmap_update_bits(w->regmap, BD70528_REG_WDT_MINUTE,
BD70528_MASK_WDT_MINUTE, bin2bcd(minutes));
if (ret) {
dev_err(w->dev, "Failed to set WDT minutes\n");
goto out_en_unlock;
}
ret = regmap_update_bits(w->regmap, BD70528_REG_WDT_SEC,
BD70528_MASK_WDT_SEC, bin2bcd(seconds));
if (ret)
dev_err(w->dev, "Failed to set WDT seconds\n");
else
dev_dbg(w->dev, "WDT tmo set to %u\n", timeout);
out_en_unlock:
ret = bd70528_wdt_set_locked(w, 1);
out_unlock:
bd70528_wdt_unlock(w->mfd);
return ret;
}
static const struct watchdog_info bd70528_wdt_info = {
.identity = "bd70528-wdt",
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
};
static const struct watchdog_ops bd70528_wdt_ops = {
.start = bd70528_wdt_start,
.stop = bd70528_wdt_stop,
.set_timeout = bd70528_wdt_set_timeout,
};
static int bd70528_wdt_probe(struct platform_device *pdev)
{
struct rohm_regmap_dev *bd70528;
struct wdtbd70528 *w;
int ret;
unsigned int reg;
bd70528 = dev_get_drvdata(pdev->dev.parent);
if (!bd70528) {
dev_err(&pdev->dev, "No MFD driver data\n");
return -EINVAL;
}
w = devm_kzalloc(&pdev->dev, sizeof(*w), GFP_KERNEL);
if (!w)
return -ENOMEM;
w->regmap = bd70528->regmap;
w->mfd = bd70528;
w->dev = &pdev->dev;
w->wdt.info = &bd70528_wdt_info;
w->wdt.ops = &bd70528_wdt_ops;
w->wdt.min_hw_heartbeat_ms = WDT_MIN_MS;
w->wdt.max_hw_heartbeat_ms = WDT_MAX_MS;
w->wdt.parent = pdev->dev.parent;
w->wdt.timeout = DEFAULT_TIMEOUT;
watchdog_set_drvdata(&w->wdt, w);
watchdog_init_timeout(&w->wdt, 0, pdev->dev.parent);
ret = bd70528_wdt_set_timeout(&w->wdt, w->wdt.timeout);
if (ret) {
dev_err(&pdev->dev, "Failed to set the watchdog timeout\n");
return ret;
}
bd70528_wdt_lock(w->mfd);
ret = regmap_read(w->regmap, BD70528_REG_WDT_CTRL, &reg);
bd70528_wdt_unlock(w->mfd);
if (ret) {
dev_err(&pdev->dev, "Failed to get the watchdog state\n");
return ret;
}
if (reg & BD70528_MASK_WDT_EN) {
dev_dbg(&pdev->dev, "watchdog was running during probe\n");
set_bit(WDOG_HW_RUNNING, &w->wdt.status);
}
ret = devm_watchdog_register_device(&pdev->dev, &w->wdt);
if (ret < 0)
dev_err(&pdev->dev, "watchdog registration failed: %d\n", ret);
return ret;
}
static struct platform_driver bd70528_wdt = {
.driver = {
.name = "bd70528-wdt"
},
.probe = bd70528_wdt_probe,
};
module_platform_driver(bd70528_wdt);
MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
MODULE_DESCRIPTION("BD70528 watchdog driver");
MODULE_LICENSE("GPL");
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