linux/drivers/watchdog/sirfsoc_wdt.c
Pratyush Anand 6551881c86 Watchdog: Fix parent of watchdog_devices
/sys/class/watchdog/watchdogn/device/modalias can help to identify the
driver/module for a given watchdog node. However, many wdt devices do not
set their parent and so, we do not see an entry for device in sysfs for
such devices.

This patch fixes parent of watchdog_device so that
/sys/class/watchdog/watchdogn/device is populated.

Exceptions: booke, diag288, octeon, softdog and w83627hf -- They do not
have any parent. Not sure, how we can identify driver for these devices.

Signed-off-by: Pratyush Anand <panand@redhat.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Maxime Coquelin <maxime.coquelin@st.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-09-09 21:39:22 +02:00

227 lines
5.6 KiB
C

/*
* Watchdog driver for CSR SiRFprimaII and SiRFatlasVI
*
* Copyright (c) 2013 Cambridge Silicon Radio Limited, a CSR plc group company.
*
* Licensed under GPLv2 or later.
*/
#include <linux/module.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
#include <linux/moduleparam.h>
#include <linux/of.h>
#include <linux/io.h>
#include <linux/uaccess.h>
#define CLOCK_FREQ 1000000
#define SIRFSOC_TIMER_COUNTER_LO 0x0000
#define SIRFSOC_TIMER_MATCH_0 0x0008
#define SIRFSOC_TIMER_INT_EN 0x0024
#define SIRFSOC_TIMER_WATCHDOG_EN 0x0028
#define SIRFSOC_TIMER_LATCH 0x0030
#define SIRFSOC_TIMER_LATCHED_LO 0x0034
#define SIRFSOC_TIMER_WDT_INDEX 5
#define SIRFSOC_WDT_MIN_TIMEOUT 30 /* 30 secs */
#define SIRFSOC_WDT_MAX_TIMEOUT (10 * 60) /* 10 mins */
#define SIRFSOC_WDT_DEFAULT_TIMEOUT 30 /* 30 secs */
static unsigned int timeout = SIRFSOC_WDT_DEFAULT_TIMEOUT;
static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(timeout, uint, 0);
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(timeout, "Default watchdog timeout (in seconds)");
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
static unsigned int sirfsoc_wdt_gettimeleft(struct watchdog_device *wdd)
{
u32 counter, match;
void __iomem *wdt_base;
int time_left;
wdt_base = watchdog_get_drvdata(wdd);
counter = readl(wdt_base + SIRFSOC_TIMER_COUNTER_LO);
match = readl(wdt_base +
SIRFSOC_TIMER_MATCH_0 + (SIRFSOC_TIMER_WDT_INDEX << 2));
time_left = match - counter;
return time_left / CLOCK_FREQ;
}
static int sirfsoc_wdt_updatetimeout(struct watchdog_device *wdd)
{
u32 counter, timeout_ticks;
void __iomem *wdt_base;
timeout_ticks = wdd->timeout * CLOCK_FREQ;
wdt_base = watchdog_get_drvdata(wdd);
/* Enable the latch before reading the LATCH_LO register */
writel(1, wdt_base + SIRFSOC_TIMER_LATCH);
/* Set the TO value */
counter = readl(wdt_base + SIRFSOC_TIMER_LATCHED_LO);
counter += timeout_ticks;
writel(counter, wdt_base +
SIRFSOC_TIMER_MATCH_0 + (SIRFSOC_TIMER_WDT_INDEX << 2));
return 0;
}
static int sirfsoc_wdt_enable(struct watchdog_device *wdd)
{
void __iomem *wdt_base = watchdog_get_drvdata(wdd);
sirfsoc_wdt_updatetimeout(wdd);
/*
* NOTE: If interrupt is not enabled
* then WD-Reset doesn't get generated at all.
*/
writel(readl(wdt_base + SIRFSOC_TIMER_INT_EN)
| (1 << SIRFSOC_TIMER_WDT_INDEX),
wdt_base + SIRFSOC_TIMER_INT_EN);
writel(1, wdt_base + SIRFSOC_TIMER_WATCHDOG_EN);
return 0;
}
static int sirfsoc_wdt_disable(struct watchdog_device *wdd)
{
void __iomem *wdt_base = watchdog_get_drvdata(wdd);
writel(0, wdt_base + SIRFSOC_TIMER_WATCHDOG_EN);
writel(readl(wdt_base + SIRFSOC_TIMER_INT_EN)
& (~(1 << SIRFSOC_TIMER_WDT_INDEX)),
wdt_base + SIRFSOC_TIMER_INT_EN);
return 0;
}
static int sirfsoc_wdt_settimeout(struct watchdog_device *wdd, unsigned int to)
{
wdd->timeout = to;
sirfsoc_wdt_updatetimeout(wdd);
return 0;
}
#define OPTIONS (WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE)
static const struct watchdog_info sirfsoc_wdt_ident = {
.options = OPTIONS,
.firmware_version = 0,
.identity = "SiRFSOC Watchdog",
};
static struct watchdog_ops sirfsoc_wdt_ops = {
.owner = THIS_MODULE,
.start = sirfsoc_wdt_enable,
.stop = sirfsoc_wdt_disable,
.get_timeleft = sirfsoc_wdt_gettimeleft,
.ping = sirfsoc_wdt_updatetimeout,
.set_timeout = sirfsoc_wdt_settimeout,
};
static struct watchdog_device sirfsoc_wdd = {
.info = &sirfsoc_wdt_ident,
.ops = &sirfsoc_wdt_ops,
.timeout = SIRFSOC_WDT_DEFAULT_TIMEOUT,
.min_timeout = SIRFSOC_WDT_MIN_TIMEOUT,
.max_timeout = SIRFSOC_WDT_MAX_TIMEOUT,
};
static int sirfsoc_wdt_probe(struct platform_device *pdev)
{
struct resource *res;
int ret;
void __iomem *base;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(base))
return PTR_ERR(base);
watchdog_set_drvdata(&sirfsoc_wdd, base);
watchdog_init_timeout(&sirfsoc_wdd, timeout, &pdev->dev);
watchdog_set_nowayout(&sirfsoc_wdd, nowayout);
sirfsoc_wdd.parent = &pdev->dev;
ret = watchdog_register_device(&sirfsoc_wdd);
if (ret)
return ret;
platform_set_drvdata(pdev, &sirfsoc_wdd);
return 0;
}
static void sirfsoc_wdt_shutdown(struct platform_device *pdev)
{
struct watchdog_device *wdd = platform_get_drvdata(pdev);
sirfsoc_wdt_disable(wdd);
}
static int sirfsoc_wdt_remove(struct platform_device *pdev)
{
sirfsoc_wdt_shutdown(pdev);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int sirfsoc_wdt_suspend(struct device *dev)
{
return 0;
}
static int sirfsoc_wdt_resume(struct device *dev)
{
struct watchdog_device *wdd = dev_get_drvdata(dev);
/*
* NOTE: Since timer controller registers settings are saved
* and restored back by the timer-prima2.c, so we need not
* update WD settings except refreshing timeout.
*/
sirfsoc_wdt_updatetimeout(wdd);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(sirfsoc_wdt_pm_ops,
sirfsoc_wdt_suspend, sirfsoc_wdt_resume);
static const struct of_device_id sirfsoc_wdt_of_match[] = {
{ .compatible = "sirf,prima2-tick"},
{},
};
MODULE_DEVICE_TABLE(of, sirfsoc_wdt_of_match);
static struct platform_driver sirfsoc_wdt_driver = {
.driver = {
.name = "sirfsoc-wdt",
.pm = &sirfsoc_wdt_pm_ops,
.of_match_table = sirfsoc_wdt_of_match,
},
.probe = sirfsoc_wdt_probe,
.remove = sirfsoc_wdt_remove,
.shutdown = sirfsoc_wdt_shutdown,
};
module_platform_driver(sirfsoc_wdt_driver);
MODULE_DESCRIPTION("SiRF SoC watchdog driver");
MODULE_AUTHOR("Xianglong Du <Xianglong.Du@csr.com>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:sirfsoc-wdt");