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watchdog: sp5100_tco: Convert to use watchdog subsystem 

Convert to watchdog subsystem. As part of that rework, use devm functions
where possible, and replace almost all static variables with a dynamically
allocated data structure.

Cc: Zoltán Böszörményi <zboszor@pr.hu>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
hifive-unleashed-5.1
Guenter Roeck 2017-12-24 13:04:14 -08:00 committed by Wim Van Sebroeck
parent 5bbecc5d34
commit 7cd9d5fff7
1 changed files with 102 additions and 256 deletions
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358
drivers/watchdog/sp5100_tco.c
View File

@ -24,37 +24,31 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/init.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/pci.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include <linux/types.h>
#include <linux/watchdog.h>
#include "sp5100_tco.h"
/* Module and version information */
#define TCO_VERSION "0.05"
#define TCO_MODULE_NAME "SP5100 TCO timer"
#define TCO_DRIVER_NAME TCO_MODULE_NAME ", v" TCO_VERSION
#define TCO_DRIVER_NAME "sp5100-tco"
/* internal variables */
static u32 tcobase_phys;
static u32 tco_wdt_fired;
static void __iomem *tcobase;
static DEFINE_SPINLOCK(tco_lock); /* Guards the hardware */
static unsigned long timer_alive;
static char tco_expect_close;
static struct pci_dev *sp5100_tco_pci;
struct sp5100_tco {
struct watchdog_device wdd;
void __iomem *tcobase;
};
/* the watchdog platform device */
static struct platform_device *sp5100_tco_platform_device;
/* the associated PCI device */
static struct pci_dev *sp5100_tco_pci;
/* module parameters */
@ -79,55 +73,52 @@ static bool tco_has_sp5100_reg_layout(struct pci_dev *dev)
dev->revision < 0x40;
}
static void tco_timer_start(void)
static int tco_timer_start(struct watchdog_device *wdd)
{
struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
u32 val;
unsigned long flags;
spin_lock_irqsave(&tco_lock, flags);
val = readl(SP5100_WDT_CONTROL(tcobase));
val = readl(SP5100_WDT_CONTROL(tco->tcobase));
val |= SP5100_WDT_START_STOP_BIT;
writel(val, SP5100_WDT_CONTROL(tcobase));
spin_unlock_irqrestore(&tco_lock, flags);
writel(val, SP5100_WDT_CONTROL(tco->tcobase));
return 0;
}
static void tco_timer_stop(void)
static int tco_timer_stop(struct watchdog_device *wdd)
{
struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
u32 val;
unsigned long flags;
spin_lock_irqsave(&tco_lock, flags);
val = readl(SP5100_WDT_CONTROL(tcobase));
val = readl(SP5100_WDT_CONTROL(tco->tcobase));
val &= ~SP5100_WDT_START_STOP_BIT;
writel(val, SP5100_WDT_CONTROL(tcobase));
spin_unlock_irqrestore(&tco_lock, flags);
writel(val, SP5100_WDT_CONTROL(tco->tcobase));
return 0;
}
static void tco_timer_keepalive(void)
static int tco_timer_ping(struct watchdog_device *wdd)
{
struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
u32 val;
unsigned long flags;
spin_lock_irqsave(&tco_lock, flags);
val = readl(SP5100_WDT_CONTROL(tcobase));
val = readl(SP5100_WDT_CONTROL(tco->tcobase));
val |= SP5100_WDT_TRIGGER_BIT;
writel(val, SP5100_WDT_CONTROL(tcobase));
spin_unlock_irqrestore(&tco_lock, flags);
writel(val, SP5100_WDT_CONTROL(tco->tcobase));
return 0;
}
static int tco_timer_set_heartbeat(int t)
static int tco_timer_set_timeout(struct watchdog_device *wdd,
unsigned int t)
{
unsigned long flags;
if (t < 0 || t > 0xffff)
return -EINVAL;
struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
/* Write new heartbeat to watchdog */
spin_lock_irqsave(&tco_lock, flags);
writel(t, SP5100_WDT_COUNT(tcobase));
spin_unlock_irqrestore(&tco_lock, flags);
writel(t, SP5100_WDT_COUNT(tco->tcobase));
wdd->timeout = t;
heartbeat = t;
return 0;
}
@ -182,137 +173,7 @@ static void tco_timer_enable(void)
}
}
/*
* /dev/watchdog handling
*/
static int sp5100_tco_open(struct inode *inode, struct file *file)
{
/* /dev/watchdog can only be opened once */
if (test_and_set_bit(0, &timer_alive))
return -EBUSY;
/* Reload and activate timer */
tco_timer_start();
tco_timer_keepalive();
return nonseekable_open(inode, file);
}
static int sp5100_tco_release(struct inode *inode, struct file *file)
{
/* Shut off the timer. */
if (tco_expect_close == 42) {
tco_timer_stop();
} else {
pr_crit("Unexpected close, not stopping watchdog!\n");
tco_timer_keepalive();
}
clear_bit(0, &timer_alive);
tco_expect_close = 0;
return 0;
}
static ssize_t sp5100_tco_write(struct file *file, const char __user *data,
size_t len, loff_t *ppos)
{
/* See if we got the magic character 'V' and reload the timer */
if (len) {
if (!nowayout) {
size_t i;
/* note: just in case someone wrote the magic character
* five months ago... */
tco_expect_close = 0;
/* scan to see whether or not we got the magic character
*/
for (i = 0; i != len; i++) {
char c;
if (get_user(c, data + i))
return -EFAULT;
if (c == 'V')
tco_expect_close = 42;
}
}
/* someone wrote to us, we should reload the timer */
tco_timer_keepalive();
}
return len;
}
static long sp5100_tco_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
int new_options, retval = -EINVAL;
int new_heartbeat;
void __user *argp = (void __user *)arg;
int __user *p = argp;
static const struct watchdog_info ident = {
.options = WDIOF_SETTIMEOUT |
WDIOF_KEEPALIVEPING |
WDIOF_MAGICCLOSE,
.firmware_version = 0,
.identity = TCO_MODULE_NAME,
};
switch (cmd) {
case WDIOC_GETSUPPORT:
return copy_to_user(argp, &ident,
sizeof(ident)) ? -EFAULT : 0;
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
return put_user(0, p);
case WDIOC_SETOPTIONS:
if (get_user(new_options, p))
return -EFAULT;
if (new_options & WDIOS_DISABLECARD) {
tco_timer_stop();
retval = 0;
}
if (new_options & WDIOS_ENABLECARD) {
tco_timer_start();
tco_timer_keepalive();
retval = 0;
}
return retval;
case WDIOC_KEEPALIVE:
tco_timer_keepalive();
return 0;
case WDIOC_SETTIMEOUT:
if (get_user(new_heartbeat, p))
return -EFAULT;
if (tco_timer_set_heartbeat(new_heartbeat))
return -EINVAL;
tco_timer_keepalive();
/* Fall through */
case WDIOC_GETTIMEOUT:
return put_user(heartbeat, p);
default:
return -ENOTTY;
}
}
/*
* Kernel Interfaces
*/
static const struct file_operations sp5100_tco_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = sp5100_tco_write,
.unlocked_ioctl = sp5100_tco_ioctl,
.open = sp5100_tco_open,
.release = sp5100_tco_release,
};
static struct miscdevice sp5100_tco_miscdev = {
.minor = WATCHDOG_MINOR,
.name = "watchdog",
.fops = &sp5100_tco_fops,
};
static u8 sp5100_tco_read_pm_reg32(u8 index)
static u32 sp5100_tco_read_pm_reg32(u8 index)
{
u32 val = 0;
int i;
@ -323,14 +184,13 @@ static u8 sp5100_tco_read_pm_reg32(u8 index)
return val;
}
/*
* Init & exit routines
*/
static int sp5100_tco_setupdevice(struct device *dev)
static int sp5100_tco_setupdevice(struct device *dev,
struct watchdog_device *wdd)
{
const char *dev_name = NULL;
u32 val;
struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
const char *dev_name;
u8 base_addr;
u32 val;
int ret;
/*
@ -361,8 +221,8 @@ static int sp5100_tco_setupdevice(struct device *dev)
dev_dbg(dev, "Got 0x%04x from indirect I/O\n", val);
/* Check MMIO address conflict */
if (!request_mem_region_exclusive(val, SP5100_WDT_MEM_MAP_SIZE,
dev_name)) {
if (!devm_request_mem_region(dev, val, SP5100_WDT_MEM_MAP_SIZE,
dev_name)) {
dev_dbg(dev, "MMIO address 0x%04x already in use\n", val);
/*
* Secondly, Find the watchdog timer MMIO address
@ -391,8 +251,8 @@ static int sp5100_tco_setupdevice(struct device *dev)
/* Add the Watchdog Timer offset to base address. */
val += SB800_PM_WDT_MMIO_OFFSET;
/* Check MMIO address conflict */
if (!request_mem_region_exclusive(val, SP5100_WDT_MEM_MAP_SIZE,
dev_name)) {
if (!devm_request_mem_region(dev, val, SP5100_WDT_MEM_MAP_SIZE,
dev_name)) {
dev_dbg(dev, "MMIO address 0x%04x already in use\n",
val);
ret = -EBUSY;
@ -401,13 +261,11 @@ static int sp5100_tco_setupdevice(struct device *dev)
dev_dbg(dev, "Got 0x%04x from SBResource_MMIO register\n", val);
}
tcobase_phys = val;
tcobase = ioremap(val, SP5100_WDT_MEM_MAP_SIZE);
if (!tcobase) {
tco->tcobase = devm_ioremap(dev, val, SP5100_WDT_MEM_MAP_SIZE);
if (!tco->tcobase) {
dev_err(dev, "failed to get tcobase address\n");
ret = -ENOMEM;
goto unreg_mem_region;
goto unreg_region;
}
dev_info(dev, "Using 0x%04x for watchdog MMIO address\n", val);
@ -416,107 +274,95 @@ static int sp5100_tco_setupdevice(struct device *dev)
tco_timer_enable();
/* Check that the watchdog action is set to reset the system */
val = readl(SP5100_WDT_CONTROL(tcobase));
val = readl(SP5100_WDT_CONTROL(tco->tcobase));
/*
* Save WatchDogFired status, because WatchDogFired flag is
* cleared here.
*/
tco_wdt_fired = val & SP5100_WDT_FIRED;
if (val & SP5100_WDT_FIRED)
wdd->bootstatus = WDIOF_CARDRESET;
val &= ~SP5100_WDT_ACTION_RESET;
writel(val, SP5100_WDT_CONTROL(tcobase));
writel(val, SP5100_WDT_CONTROL(tco->tcobase));
/* Set a reasonable heartbeat before we stop the timer */
tco_timer_set_heartbeat(heartbeat);
tco_timer_set_timeout(wdd, wdd->timeout);
/*
* Stop the TCO before we change anything so we don't race with
* a zeroed timer.
*/
tco_timer_stop();
tco_timer_stop(wdd);
release_region(SP5100_IO_PM_INDEX_REG, SP5100_PM_IOPORTS_SIZE);
return 0;
unreg_mem_region:
release_mem_region(tcobase_phys, SP5100_WDT_MEM_MAP_SIZE);
unreg_region:
release_region(SP5100_IO_PM_INDEX_REG, SP5100_PM_IOPORTS_SIZE);
return ret;
}
static struct watchdog_info sp5100_tco_wdt_info = {
.identity = "SP5100 TCO timer",
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
};
static const struct watchdog_ops sp5100_tco_wdt_ops = {
.owner = THIS_MODULE,
.start = tco_timer_start,
.stop = tco_timer_stop,
.ping = tco_timer_ping,
.set_timeout = tco_timer_set_timeout,
};
static int sp5100_tco_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct watchdog_device *wdd;
struct sp5100_tco *tco;
int ret;
/*
* Check whether or not the hardware watchdog is there. If found, then
* set it up.
*/
ret = sp5100_tco_setupdevice(dev);
tco = devm_kzalloc(dev, sizeof(*tco), GFP_KERNEL);
if (!tco)
return -ENOMEM;
wdd = &tco->wdd;
wdd->parent = dev;
wdd->info = &sp5100_tco_wdt_info;
wdd->ops = &sp5100_tco_wdt_ops;
wdd->timeout = WATCHDOG_HEARTBEAT;
wdd->min_timeout = 1;
wdd->max_timeout = 0xffff;
if (watchdog_init_timeout(wdd, heartbeat, NULL))
dev_info(dev, "timeout value invalid, using %d\n",
wdd->timeout);
watchdog_set_nowayout(wdd, nowayout);
watchdog_stop_on_reboot(wdd);
watchdog_stop_on_unregister(wdd);
watchdog_set_drvdata(wdd, tco);
ret = sp5100_tco_setupdevice(dev, wdd);
if (ret)
return ret;
/* Check to see if last reboot was due to watchdog timeout */
dev_info(dev, "Last reboot was %striggered by watchdog.\n",
tco_wdt_fired ? "" : "not ");
/*
* Check that the heartbeat value is within it's range.
* If not, reset to the default.
*/
if (tco_timer_set_heartbeat(heartbeat)) {
heartbeat = WATCHDOG_HEARTBEAT;
tco_timer_set_heartbeat(heartbeat);
ret = devm_watchdog_register_device(dev, wdd);
if (ret) {
dev_err(dev, "cannot register watchdog device (err=%d)\n", ret);
return ret;
}
ret = misc_register(&sp5100_tco_miscdev);
if (ret != 0) {
dev_err(dev, "cannot register miscdev on minor=%d (err=%d)\n",
WATCHDOG_MINOR, ret);
goto exit;
}
clear_bit(0, &timer_alive);
/* Show module parameters */
dev_info(dev, "initialized (0x%p). heartbeat=%d sec (nowayout=%d)\n",
tcobase, heartbeat, nowayout);
dev_info(dev, "initialized. heartbeat=%d sec (nowayout=%d)\n",
wdd->timeout, nowayout);
return 0;
exit:
iounmap(tcobase);
release_mem_region(tcobase_phys, SP5100_WDT_MEM_MAP_SIZE);
return ret;
}
static int sp5100_tco_remove(struct platform_device *pdev)
{
/* Stop the timer before we leave */
if (!nowayout)
tco_timer_stop();
/* Deregister */
misc_deregister(&sp5100_tco_miscdev);
iounmap(tcobase);
release_mem_region(tcobase_phys, SP5100_WDT_MEM_MAP_SIZE);
return 0;
}
static void sp5100_tco_shutdown(struct platform_device *pdev)
{
tco_timer_stop();
}
static struct platform_driver sp5100_tco_driver = {
.probe = sp5100_tco_probe,
.remove = sp5100_tco_remove,
.shutdown = sp5100_tco_shutdown,
.driver = {
.name = TCO_MODULE_NAME,
.name = TCO_DRIVER_NAME,
},
};
@ -555,14 +401,14 @@ static int __init sp5100_tco_init(void)
if (!sp5100_tco_pci)
return -ENODEV;
pr_info("SP5100/SB800 TCO WatchDog Timer Driver v%s\n", TCO_VERSION);
pr_info("SP5100/SB800 TCO WatchDog Timer Driver\n");
err = platform_driver_register(&sp5100_tco_driver);
if (err)
return err;
sp5100_tco_platform_device = platform_device_register_simple(
TCO_MODULE_NAME, -1, NULL, 0);
sp5100_tco_platform_device =
platform_device_register_simple(TCO_DRIVER_NAME, -1, NULL, 0);
if (IS_ERR(sp5100_tco_platform_device)) {
err = PTR_ERR(sp5100_tco_platform_device);
goto unreg_platform_driver;