mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-24 01:41:39 +00:00
![Marcus Folkesson](/assets/img/avatar_default.png)
- Add SPDX identifier - Remove boiler plate license text - If MODULE_LICENSE and boiler plate does not match, go for boiler plate license Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com> Acked-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com> Acked-by: Baruch Siach <baruch@tkos.co.il> Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com> Acked-by: Keiji Hayashibara <hayashibara.keiji@socionext.com> Acked-by: Johannes Thumshirn <jth@kernel.org> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Mans Rullgard <mans@mansr.com> Acked-by: Matthias Brugger <matthias.bgg@gmail.com> Acked-by: Michal Simek <michal.simek@xilinx.com> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> Acked-by: Thierry Reding <treding@nvidia.com> Acked-by: Tomas Winkler <tomas.winkler@intel.com> Acked-by: Patrice Chotard <patrice.chotard@st.com> Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> Reviewed-by: Eric Anholt <eric@anholt.net> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
259 lines
6.3 KiB
C
259 lines
6.3 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Watchdog driver for the UniPhier watchdog timer
|
|
*
|
|
* (c) Copyright 2014 Panasonic Corporation
|
|
* (c) Copyright 2016 Socionext Inc.
|
|
* All rights reserved.
|
|
*/
|
|
|
|
#include <linux/bitops.h>
|
|
#include <linux/mfd/syscon.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/regmap.h>
|
|
#include <linux/watchdog.h>
|
|
|
|
/* WDT timer setting register */
|
|
#define WDTTIMSET 0x3004
|
|
#define WDTTIMSET_PERIOD_MASK (0xf << 0)
|
|
#define WDTTIMSET_PERIOD_1_SEC (0x3 << 0)
|
|
|
|
/* WDT reset selection register */
|
|
#define WDTRSTSEL 0x3008
|
|
#define WDTRSTSEL_RSTSEL_MASK (0x3 << 0)
|
|
#define WDTRSTSEL_RSTSEL_BOTH (0x0 << 0)
|
|
#define WDTRSTSEL_RSTSEL_IRQ_ONLY (0x2 << 0)
|
|
|
|
/* WDT control register */
|
|
#define WDTCTRL 0x300c
|
|
#define WDTCTRL_STATUS BIT(8)
|
|
#define WDTCTRL_CLEAR BIT(1)
|
|
#define WDTCTRL_ENABLE BIT(0)
|
|
|
|
#define SEC_TO_WDTTIMSET_PRD(sec) \
|
|
(ilog2(sec) + WDTTIMSET_PERIOD_1_SEC)
|
|
|
|
#define WDTST_TIMEOUT 1000 /* usec */
|
|
|
|
#define WDT_DEFAULT_TIMEOUT 64 /* Default is 64 seconds */
|
|
#define WDT_PERIOD_MIN 1
|
|
#define WDT_PERIOD_MAX 128
|
|
|
|
static unsigned int timeout = 0;
|
|
static bool nowayout = WATCHDOG_NOWAYOUT;
|
|
|
|
struct uniphier_wdt_dev {
|
|
struct watchdog_device wdt_dev;
|
|
struct regmap *regmap;
|
|
};
|
|
|
|
/*
|
|
* UniPhier Watchdog operations
|
|
*/
|
|
static int uniphier_watchdog_ping(struct watchdog_device *w)
|
|
{
|
|
struct uniphier_wdt_dev *wdev = watchdog_get_drvdata(w);
|
|
unsigned int val;
|
|
int ret;
|
|
|
|
/* Clear counter */
|
|
ret = regmap_write_bits(wdev->regmap, WDTCTRL,
|
|
WDTCTRL_CLEAR, WDTCTRL_CLEAR);
|
|
if (!ret)
|
|
/*
|
|
* As SoC specification, after clear counter,
|
|
* it needs to wait until counter status is 1.
|
|
*/
|
|
ret = regmap_read_poll_timeout(wdev->regmap, WDTCTRL, val,
|
|
(val & WDTCTRL_STATUS),
|
|
0, WDTST_TIMEOUT);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int __uniphier_watchdog_start(struct regmap *regmap, unsigned int sec)
|
|
{
|
|
unsigned int val;
|
|
int ret;
|
|
|
|
ret = regmap_read_poll_timeout(regmap, WDTCTRL, val,
|
|
!(val & WDTCTRL_STATUS),
|
|
0, WDTST_TIMEOUT);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/* Setup period */
|
|
ret = regmap_write(regmap, WDTTIMSET,
|
|
SEC_TO_WDTTIMSET_PRD(sec));
|
|
if (ret)
|
|
return ret;
|
|
|
|
/* Enable and clear watchdog */
|
|
ret = regmap_write(regmap, WDTCTRL, WDTCTRL_ENABLE | WDTCTRL_CLEAR);
|
|
if (!ret)
|
|
/*
|
|
* As SoC specification, after clear counter,
|
|
* it needs to wait until counter status is 1.
|
|
*/
|
|
ret = regmap_read_poll_timeout(regmap, WDTCTRL, val,
|
|
(val & WDTCTRL_STATUS),
|
|
0, WDTST_TIMEOUT);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int __uniphier_watchdog_stop(struct regmap *regmap)
|
|
{
|
|
/* Disable and stop watchdog */
|
|
return regmap_write_bits(regmap, WDTCTRL, WDTCTRL_ENABLE, 0);
|
|
}
|
|
|
|
static int __uniphier_watchdog_restart(struct regmap *regmap, unsigned int sec)
|
|
{
|
|
int ret;
|
|
|
|
ret = __uniphier_watchdog_stop(regmap);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return __uniphier_watchdog_start(regmap, sec);
|
|
}
|
|
|
|
static int uniphier_watchdog_start(struct watchdog_device *w)
|
|
{
|
|
struct uniphier_wdt_dev *wdev = watchdog_get_drvdata(w);
|
|
unsigned int tmp_timeout;
|
|
|
|
tmp_timeout = roundup_pow_of_two(w->timeout);
|
|
|
|
return __uniphier_watchdog_start(wdev->regmap, tmp_timeout);
|
|
}
|
|
|
|
static int uniphier_watchdog_stop(struct watchdog_device *w)
|
|
{
|
|
struct uniphier_wdt_dev *wdev = watchdog_get_drvdata(w);
|
|
|
|
return __uniphier_watchdog_stop(wdev->regmap);
|
|
}
|
|
|
|
static int uniphier_watchdog_set_timeout(struct watchdog_device *w,
|
|
unsigned int t)
|
|
{
|
|
struct uniphier_wdt_dev *wdev = watchdog_get_drvdata(w);
|
|
unsigned int tmp_timeout;
|
|
int ret;
|
|
|
|
tmp_timeout = roundup_pow_of_two(t);
|
|
if (tmp_timeout == w->timeout)
|
|
return 0;
|
|
|
|
if (watchdog_active(w)) {
|
|
ret = __uniphier_watchdog_restart(wdev->regmap, tmp_timeout);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
w->timeout = tmp_timeout;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Kernel Interfaces
|
|
*/
|
|
static const struct watchdog_info uniphier_wdt_info = {
|
|
.identity = "uniphier-wdt",
|
|
.options = WDIOF_SETTIMEOUT |
|
|
WDIOF_KEEPALIVEPING |
|
|
WDIOF_MAGICCLOSE |
|
|
WDIOF_OVERHEAT,
|
|
};
|
|
|
|
static const struct watchdog_ops uniphier_wdt_ops = {
|
|
.owner = THIS_MODULE,
|
|
.start = uniphier_watchdog_start,
|
|
.stop = uniphier_watchdog_stop,
|
|
.ping = uniphier_watchdog_ping,
|
|
.set_timeout = uniphier_watchdog_set_timeout,
|
|
};
|
|
|
|
static int uniphier_wdt_probe(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct uniphier_wdt_dev *wdev;
|
|
struct regmap *regmap;
|
|
struct device_node *parent;
|
|
int ret;
|
|
|
|
wdev = devm_kzalloc(dev, sizeof(*wdev), GFP_KERNEL);
|
|
if (!wdev)
|
|
return -ENOMEM;
|
|
|
|
platform_set_drvdata(pdev, wdev);
|
|
|
|
parent = of_get_parent(dev->of_node); /* parent should be syscon node */
|
|
regmap = syscon_node_to_regmap(parent);
|
|
of_node_put(parent);
|
|
if (IS_ERR(regmap))
|
|
return PTR_ERR(regmap);
|
|
|
|
wdev->regmap = regmap;
|
|
wdev->wdt_dev.info = &uniphier_wdt_info;
|
|
wdev->wdt_dev.ops = &uniphier_wdt_ops;
|
|
wdev->wdt_dev.max_timeout = WDT_PERIOD_MAX;
|
|
wdev->wdt_dev.min_timeout = WDT_PERIOD_MIN;
|
|
wdev->wdt_dev.timeout = WDT_DEFAULT_TIMEOUT;
|
|
wdev->wdt_dev.parent = dev;
|
|
|
|
watchdog_init_timeout(&wdev->wdt_dev, timeout, dev);
|
|
watchdog_set_nowayout(&wdev->wdt_dev, nowayout);
|
|
watchdog_stop_on_reboot(&wdev->wdt_dev);
|
|
|
|
watchdog_set_drvdata(&wdev->wdt_dev, wdev);
|
|
|
|
uniphier_watchdog_stop(&wdev->wdt_dev);
|
|
ret = regmap_write(wdev->regmap, WDTRSTSEL, WDTRSTSEL_RSTSEL_BOTH);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = devm_watchdog_register_device(dev, &wdev->wdt_dev);
|
|
if (ret)
|
|
return ret;
|
|
|
|
dev_info(dev, "watchdog driver (timeout=%d sec, nowayout=%d)\n",
|
|
wdev->wdt_dev.timeout, nowayout);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id uniphier_wdt_dt_ids[] = {
|
|
{ .compatible = "socionext,uniphier-wdt" },
|
|
{ /* sentinel */ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, uniphier_wdt_dt_ids);
|
|
|
|
static struct platform_driver uniphier_wdt_driver = {
|
|
.probe = uniphier_wdt_probe,
|
|
.driver = {
|
|
.name = "uniphier-wdt",
|
|
.of_match_table = uniphier_wdt_dt_ids,
|
|
},
|
|
};
|
|
|
|
module_platform_driver(uniphier_wdt_driver);
|
|
|
|
module_param(timeout, uint, 0000);
|
|
MODULE_PARM_DESC(timeout,
|
|
"Watchdog timeout seconds in power of 2. (0 < timeout < 128, default="
|
|
__MODULE_STRING(WDT_DEFAULT_TIMEOUT) ")");
|
|
|
|
module_param(nowayout, bool, 0000);
|
|
MODULE_PARM_DESC(nowayout,
|
|
"Watchdog cannot be stopped once started (default="
|
|
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
|
|
|
|
MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
|
|
MODULE_DESCRIPTION("UniPhier Watchdog Device Driver");
|
|
MODULE_LICENSE("GPL v2");
|