[WATCHDOG] ep93xx: implemented watchdog timer driver for TS-72xx SBCs
Technologic Systems TS-72xx SBCs have external glue logic CPLD which includes watchdog timer. This driver implements kernel support for that. Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
This commit is contained in:
Mika Westerberg
Wim Van Sebroeck
parent
64096c1741
commit
c90bf2aa94
@ -289,6 +289,17 @@ config ADX_WATCHDOG
|
||||
Say Y here if you want support for the watchdog timer on Avionic
|
||||
Design Xanthos boards.
|
||||
|
||||
config TS72XX_WATCHDOG
|
||||
tristate "TS-72XX SBC Watchdog"
|
||||
depends on MACH_TS72XX
|
||||
help
|
||||
Technologic Systems TS-7200, TS-7250 and TS-7260 boards have
|
||||
watchdog timer implemented in a external CPLD chip. Say Y here
|
||||
if you want to support for the watchdog timer on TS-72XX boards.
|
||||
|
||||
To compile this driver as a module, choose M here: the
|
||||
module will be called ts72xx_wdt.
|
||||
|
||||
# AVR32 Architecture
|
||||
|
||||
config AT32AP700X_WDT
|
||||
|
||||
@ -46,6 +46,7 @@ obj-$(CONFIG_COH901327_WATCHDOG) += coh901327_wdt.o
|
||||
obj-$(CONFIG_STMP3XXX_WATCHDOG) += stmp3xxx_wdt.o
|
||||
obj-$(CONFIG_NUC900_WATCHDOG) += nuc900_wdt.o
|
||||
obj-$(CONFIG_ADX_WATCHDOG) += adx_wdt.o
|
||||
obj-$(CONFIG_TS72XX_WATCHDOG) += ts72xx_wdt.o
|
||||
|
||||
# AVR32 Architecture
|
||||
obj-$(CONFIG_AT32AP700X_WDT) += at32ap700x_wdt.o
|
||||
|
||||
516
drivers/watchdog/ts72xx_wdt.c
Normal file
516
drivers/watchdog/ts72xx_wdt.c
Normal file
@ -0,0 +1,516 @@
|
||||
/*
|
||||
* Watchdog driver for Technologic Systems TS-72xx based SBCs
|
||||
* (TS-7200, TS-7250 and TS-7260). These boards have external
|
||||
* glue logic CPLD chip, which includes programmable watchdog
|
||||
* timer.
|
||||
*
|
||||
* Copyright (c) 2009 Mika Westerberg <mika.westerberg@iki.fi>
|
||||
*
|
||||
* This driver is based on ep93xx_wdt and wm831x_wdt drivers.
|
||||
*
|
||||
* This file is licensed under the terms of the GNU General Public
|
||||
* License version 2. This program is licensed "as is" without any
|
||||
* warranty of any kind, whether express or implied.
|
||||
*/
|
||||
|
||||
#include <linux/fs.h>
|
||||
#include <linux/io.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/moduleparam.h>
|
||||
#include <linux/miscdevice.h>
|
||||
#include <linux/mutex.h>
|
||||
#include <linux/platform_device.h>
|
||||
#include <linux/watchdog.h>
|
||||
#include <linux/uaccess.h>
|
||||
|
||||
#define TS72XX_WDT_FEED_VAL 0x05
|
||||
#define TS72XX_WDT_DEFAULT_TIMEOUT 8
|
||||
|
||||
static int timeout = TS72XX_WDT_DEFAULT_TIMEOUT;
|
||||
module_param(timeout, int, 0);
|
||||
MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. "
|
||||
"(1 <= timeout <= 8, default="
|
||||
__MODULE_STRING(TS72XX_WDT_DEFAULT_TIMEOUT)
|
||||
")");
|
||||
|
||||
static int nowayout = WATCHDOG_NOWAYOUT;
|
||||
module_param(nowayout, int, 0);
|
||||
MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close");
|
||||
|
||||
/**
|
||||
* struct ts72xx_wdt - watchdog control structure
|
||||
* @lock: lock that protects this structure
|
||||
* @regval: watchdog timeout value suitable for control register
|
||||
* @flags: flags controlling watchdog device state
|
||||
* @control_reg: watchdog control register
|
||||
* @feed_reg: watchdog feed register
|
||||
* @pdev: back pointer to platform dev
|
||||
*/
|
||||
struct ts72xx_wdt {
|
||||
struct mutex lock;
|
||||
int regval;
|
||||
|
||||
#define TS72XX_WDT_BUSY_FLAG 1
|
||||
#define TS72XX_WDT_EXPECT_CLOSE_FLAG 2
|
||||
int flags;
|
||||
|
||||
void __iomem *control_reg;
|
||||
void __iomem *feed_reg;
|
||||
|
||||
struct platform_device *pdev;
|
||||
};
|
||||
|
||||
struct platform_device *ts72xx_wdt_pdev;
|
||||
|
||||
/*
|
||||
* TS-72xx Watchdog supports following timeouts (value written
|
||||
* to control register):
|
||||
* value description
|
||||
* -------------------------
|
||||
* 0x00 watchdog disabled
|
||||
* 0x01 250ms
|
||||
* 0x02 500ms
|
||||
* 0x03 1s
|
||||
* 0x04 reserved
|
||||
* 0x05 2s
|
||||
* 0x06 4s
|
||||
* 0x07 8s
|
||||
*
|
||||
* Timeouts below 1s are not very usable so we don't
|
||||
* allow them at all.
|
||||
*
|
||||
* We provide two functions that convert between these:
|
||||
* timeout_to_regval() and regval_to_timeout().
|
||||
*/
|
||||
static const struct {
|
||||
int timeout;
|
||||
int regval;
|
||||
} ts72xx_wdt_map[] = {
|
||||
{ 1, 3 },
|
||||
{ 2, 5 },
|
||||
{ 4, 6 },
|
||||
{ 8, 7 },
|
||||
};
|
||||
|
||||
/**
|
||||
* timeout_to_regval() - converts given timeout to control register value
|
||||
* @new_timeout: timeout in seconds to be converted
|
||||
*
|
||||
* Function converts given @new_timeout into valid value that can
|
||||
* be programmed into watchdog control register. When conversion is
|
||||
* not possible, function returns %-EINVAL.
|
||||
*/
|
||||
static int timeout_to_regval(int new_timeout)
|
||||
{
|
||||
int i;
|
||||
|
||||
/* first limit it to 1 - 8 seconds */
|
||||
new_timeout = clamp_val(new_timeout, 1, 8);
|
||||
|
||||
for (i = 0; i < ARRAY_SIZE(ts72xx_wdt_map); i++) {
|
||||
if (ts72xx_wdt_map[i].timeout >= new_timeout)
|
||||
return ts72xx_wdt_map[i].regval;
|
||||
}
|
||||
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/**
|
||||
* regval_to_timeout() - converts control register value to timeout
|
||||
* @regval: control register value to be converted
|
||||
*
|
||||
* Function converts given @regval to timeout in seconds (1, 2, 4 or 8).
|
||||
* If @regval cannot be converted, function returns %-EINVAL.
|
||||
*/
|
||||
static int regval_to_timeout(int regval)
|
||||
{
|
||||
int i;
|
||||
|
||||
for (i = 0; i < ARRAY_SIZE(ts72xx_wdt_map); i++) {
|
||||
if (ts72xx_wdt_map[i].regval == regval)
|
||||
return ts72xx_wdt_map[i].timeout;
|
||||
}
|
||||
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/**
|
||||
* ts72xx_wdt_kick() - kick the watchdog
|
||||
* @wdt: watchdog to be kicked
|
||||
*
|
||||
* Called with @wdt->lock held.
|
||||
*/
|
||||
static inline void ts72xx_wdt_kick(struct ts72xx_wdt *wdt)
|
||||
{
|
||||
__raw_writeb(TS72XX_WDT_FEED_VAL, wdt->feed_reg);
|
||||
}
|
||||
|
||||
/**
|
||||
* ts72xx_wdt_start() - starts the watchdog timer
|
||||
* @wdt: watchdog to be started
|
||||
*
|
||||
* This function programs timeout to watchdog timer
|
||||
* and starts it.
|
||||
*
|
||||
* Called with @wdt->lock held.
|
||||
*/
|
||||
static void ts72xx_wdt_start(struct ts72xx_wdt *wdt)
|
||||
{
|
||||
/*
|
||||
* To program the wdt, it first must be "fed" and
|
||||
* only after that (within 30 usecs) the configuration
|
||||
* can be changed.
|
||||
*/
|
||||
ts72xx_wdt_kick(wdt);
|
||||
__raw_writeb((u8)wdt->regval, wdt->control_reg);
|
||||
}
|
||||
|
||||
/**
|
||||
* ts72xx_wdt_stop() - stops the watchdog timer
|
||||
* @wdt: watchdog to be stopped
|
||||
*
|
||||
* Called with @wdt->lock held.
|
||||
*/
|
||||
static void ts72xx_wdt_stop(struct ts72xx_wdt *wdt)
|
||||
{
|
||||
ts72xx_wdt_kick(wdt);
|
||||
__raw_writeb(0, wdt->control_reg);
|
||||
}
|
||||
|
||||
static int ts72xx_wdt_open(struct inode *inode, struct file *file)
|
||||
{
|
||||
struct ts72xx_wdt *wdt = platform_get_drvdata(ts72xx_wdt_pdev);
|
||||
int regval;
|
||||
|
||||
/*
|
||||
* Try to convert default timeout to valid register
|
||||
* value first.
|
||||
*/
|
||||
regval = timeout_to_regval(timeout);
|
||||
if (regval < 0) {
|
||||
dev_err(&wdt->pdev->dev,
|
||||
"failed to convert timeout (%d) to register value\n",
|
||||
timeout);
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
if (mutex_lock_interruptible(&wdt->lock))
|
||||
return -ERESTARTSYS;
|
||||
|
||||
if ((wdt->flags & TS72XX_WDT_BUSY_FLAG) != 0) {
|
||||
mutex_unlock(&wdt->lock);
|
||||
return -EBUSY;
|
||||
}
|
||||
|
||||
wdt->flags = TS72XX_WDT_BUSY_FLAG;
|
||||
wdt->regval = regval;
|
||||
file->private_data = wdt;
|
||||
|
||||
ts72xx_wdt_start(wdt);
|
||||
|
||||
mutex_unlock(&wdt->lock);
|
||||
return nonseekable_open(inode, file);
|
||||
}
|
||||
|
||||
static int ts72xx_wdt_release(struct inode *inode, struct file *file)
|
||||
{
|
||||
struct ts72xx_wdt *wdt = file->private_data;
|
||||
|
||||
if (mutex_lock_interruptible(&wdt->lock))
|
||||
return -ERESTARTSYS;
|
||||
|
||||
if ((wdt->flags & TS72XX_WDT_EXPECT_CLOSE_FLAG) != 0) {
|
||||
ts72xx_wdt_stop(wdt);
|
||||
} else {
|
||||
dev_warn(&wdt->pdev->dev,
|
||||
"TS-72XX WDT device closed unexpectly. "
|
||||
"Watchdog timer will not stop!\n");
|
||||
/*
|
||||
* Kick it one more time, to give userland some time
|
||||
* to recover (for example, respawning the kicker
|
||||
* daemon).
|
||||
*/
|
||||
ts72xx_wdt_kick(wdt);
|
||||
}
|
||||
|
||||
wdt->flags = 0;
|
||||
|
||||
mutex_unlock(&wdt->lock);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static ssize_t ts72xx_wdt_write(struct file *file,
|
||||
const char __user *data,
|
||||
size_t len,
|
||||
loff_t *ppos)
|
||||
{
|
||||
struct ts72xx_wdt *wdt = file->private_data;
|
||||
|
||||
if (!len)
|
||||
return 0;
|
||||
|
||||
if (mutex_lock_interruptible(&wdt->lock))
|
||||
return -ERESTARTSYS;
|
||||
|
||||
ts72xx_wdt_kick(wdt);
|
||||
|
||||
/*
|
||||
* Support for magic character closing. User process
|
||||
* writes 'V' into the device, just before it is closed.
|
||||
* This means that we know that the wdt timer can be
|
||||
* stopped after user closes the device.
|
||||
*/
|
||||
if (!nowayout) {
|
||||
int i;
|
||||
|
||||
for (i = 0; i < len; i++) {
|
||||
char c;
|
||||
|
||||
/* In case it was set long ago */
|
||||
wdt->flags &= ~TS72XX_WDT_EXPECT_CLOSE_FLAG;
|
||||
|
||||
if (get_user(c, data + i)) {
|
||||
mutex_unlock(&wdt->lock);
|
||||
return -EFAULT;
|
||||
}
|
||||
if (c == 'V') {
|
||||
wdt->flags |= TS72XX_WDT_EXPECT_CLOSE_FLAG;
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
mutex_unlock(&wdt->lock);
|
||||
return len;
|
||||
}
|
||||
|
||||
static const struct watchdog_info winfo = {
|
||||
.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT |
|
||||
WDIOF_MAGICCLOSE,
|
||||
.firmware_version = 1,
|
||||
.identity = "TS-72XX WDT",
|
||||
};
|
||||
|
||||
static long ts72xx_wdt_ioctl(struct file *file, unsigned int cmd,
|
||||
unsigned long arg)
|
||||
{
|
||||
struct ts72xx_wdt *wdt = file->private_data;
|
||||
void __user *argp = (void __user *)arg;
|
||||
int __user *p = (int __user *)argp;
|
||||
int error = 0;
|
||||
|
||||
if (mutex_lock_interruptible(&wdt->lock))
|
||||
return -ERESTARTSYS;
|
||||
|
||||
switch (cmd) {
|
||||
case WDIOC_GETSUPPORT:
|
||||
error = copy_to_user(argp, &winfo, sizeof(winfo));
|
||||
break;
|
||||
|
||||
case WDIOC_KEEPALIVE:
|
||||
ts72xx_wdt_kick(wdt);
|
||||
break;
|
||||
|
||||
case WDIOC_SETOPTIONS: {
|
||||
int options;
|
||||
|
||||
if (get_user(options, p)) {
|
||||
error = -EFAULT;
|
||||
break;
|
||||
}
|
||||
|
||||
error = -EINVAL;
|
||||
|
||||
if ((options & WDIOS_DISABLECARD) != 0) {
|
||||
ts72xx_wdt_stop(wdt);
|
||||
error = 0;
|
||||
}
|
||||
if ((options & WDIOS_ENABLECARD) != 0) {
|
||||
ts72xx_wdt_start(wdt);
|
||||
error = 0;
|
||||
}
|
||||
|
||||
break;
|
||||
}
|
||||
|
||||
case WDIOC_SETTIMEOUT: {
|
||||
int new_timeout;
|
||||
|
||||
if (get_user(new_timeout, p)) {
|
||||
error = -EFAULT;
|
||||
} else {
|
||||
int regval;
|
||||
|
||||
regval = timeout_to_regval(new_timeout);
|
||||
if (regval < 0) {
|
||||
error = -EINVAL;
|
||||
} else {
|
||||
ts72xx_wdt_stop(wdt);
|
||||
wdt->regval = regval;
|
||||
ts72xx_wdt_start(wdt);
|
||||
}
|
||||
}
|
||||
if (error)
|
||||
break;
|
||||
|
||||
/*FALLTHROUGH*/
|
||||
}
|
||||
|
||||
case WDIOC_GETTIMEOUT:
|
||||
if (put_user(regval_to_timeout(wdt->regval), p))
|
||||
error = -EFAULT;
|
||||
break;
|
||||
|
||||
default:
|
||||
error = -ENOTTY;
|
||||
break;
|
||||
}
|
||||
|
||||
mutex_unlock(&wdt->lock);
|
||||
return error;
|
||||
}
|
||||
|
||||
static const struct file_operations ts72xx_wdt_fops = {
|
||||
.owner = THIS_MODULE,
|
||||
.llseek = no_llseek,
|
||||
.open = ts72xx_wdt_open,
|
||||
.release = ts72xx_wdt_release,
|
||||
.write = ts72xx_wdt_write,
|
||||
.unlocked_ioctl = ts72xx_wdt_ioctl,
|
||||
};
|
||||
|
||||
static struct miscdevice ts72xx_wdt_miscdev = {
|
||||
.minor = WATCHDOG_MINOR,
|
||||
.name = "watchdog",
|
||||
.fops = &ts72xx_wdt_fops,
|
||||
};
|
||||
|
||||
static __devinit int ts72xx_wdt_probe(struct platform_device *pdev)
|
||||
{
|
||||
struct ts72xx_wdt *wdt;
|
||||
struct resource *r1, *r2;
|
||||
int error = 0;
|
||||
|
||||
wdt = kzalloc(sizeof(struct ts72xx_wdt), GFP_KERNEL);
|
||||
if (!wdt) {
|
||||
dev_err(&pdev->dev, "failed to allocate memory\n");
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
r1 = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
||||
if (!r1) {
|
||||
dev_err(&pdev->dev, "failed to get memory resource\n");
|
||||
error = -ENODEV;
|
||||
goto fail;
|
||||
}
|
||||
|
||||
r1 = request_mem_region(r1->start, resource_size(r1), pdev->name);
|
||||
if (!r1) {
|
||||
dev_err(&pdev->dev, "cannot request memory region\n");
|
||||
error = -EBUSY;
|
||||
goto fail;
|
||||
}
|
||||
|
||||
wdt->control_reg = ioremap(r1->start, resource_size(r1));
|
||||
if (!wdt->control_reg) {
|
||||
dev_err(&pdev->dev, "failed to map memory\n");
|
||||
error = -ENODEV;
|
||||
goto fail_free_control;
|
||||
}
|
||||
|
||||
r2 = platform_get_resource(pdev, IORESOURCE_MEM, 1);
|
||||
if (!r2) {
|
||||
dev_err(&pdev->dev, "failed to get memory resource\n");
|
||||
error = -ENODEV;
|
||||
goto fail_unmap_control;
|
||||
}
|
||||
|
||||
r2 = request_mem_region(r2->start, resource_size(r2), pdev->name);
|
||||
if (!r2) {
|
||||
dev_err(&pdev->dev, "cannot request memory region\n");
|
||||
error = -EBUSY;
|
||||
goto fail_unmap_control;
|
||||
}
|
||||
|
||||
wdt->feed_reg = ioremap(r2->start, resource_size(r2));
|
||||
if (!wdt->feed_reg) {
|
||||
dev_err(&pdev->dev, "failed to map memory\n");
|
||||
error = -ENODEV;
|
||||
goto fail_free_feed;
|
||||
}
|
||||
|
||||
platform_set_drvdata(pdev, wdt);
|
||||
ts72xx_wdt_pdev = pdev;
|
||||
wdt->pdev = pdev;
|
||||
mutex_init(&wdt->lock);
|
||||
|
||||
error = misc_register(&ts72xx_wdt_miscdev);
|
||||
if (error) {
|
||||
dev_err(&pdev->dev, "failed to register miscdev\n");
|
||||
goto fail_unmap_feed;
|
||||
}
|
||||
|
||||
dev_info(&pdev->dev, "TS-72xx Watchdog driver\n");
|
||||
|
||||
return 0;
|
||||
|
||||
fail_unmap_feed:
|
||||
platform_set_drvdata(pdev, NULL);
|
||||
iounmap(wdt->feed_reg);
|
||||
fail_free_feed:
|
||||
release_mem_region(r2->start, resource_size(r2));
|
||||
fail_unmap_control:
|
||||
iounmap(wdt->control_reg);
|
||||
fail_free_control:
|
||||
release_mem_region(r1->start, resource_size(r1));
|
||||
fail:
|
||||
kfree(wdt);
|
||||
return error;
|
||||
}
|
||||
|
||||
static __devexit int ts72xx_wdt_remove(struct platform_device *pdev)
|
||||
{
|
||||
struct ts72xx_wdt *wdt = platform_get_drvdata(pdev);
|
||||
struct resource *res;
|
||||
int error;
|
||||
|
||||
error = misc_deregister(&ts72xx_wdt_miscdev);
|
||||
platform_set_drvdata(pdev, NULL);
|
||||
|
||||
iounmap(wdt->control_reg);
|
||||
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
||||
release_mem_region(res->start, resource_size(res));
|
||||
|
||||
iounmap(wdt->feed_reg);
|
||||
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
|
||||
release_mem_region(res->start, resource_size(res));
|
||||
|
||||
kfree(wdt);
|
||||
return error;
|
||||
}
|
||||
|
||||
static struct platform_driver ts72xx_wdt_driver = {
|
||||
.probe = ts72xx_wdt_probe,
|
||||
.remove = __devexit_p(ts72xx_wdt_remove),
|
||||
.driver = {
|
||||
.name = "ts72xx-wdt",
|
||||
.owner = THIS_MODULE,
|
||||
},
|
||||
};
|
||||
|
||||
static __init int ts72xx_wdt_init(void)
|
||||
{
|
||||
return platform_driver_register(&ts72xx_wdt_driver);
|
||||
}
|
||||
module_init(ts72xx_wdt_init);
|
||||
|
||||
static __exit void ts72xx_wdt_exit(void)
|
||||
{
|
||||
platform_driver_unregister(&ts72xx_wdt_driver);
|
||||
}
|
||||
module_exit(ts72xx_wdt_exit);
|
||||
|
||||
MODULE_AUTHOR("Mika Westerberg <mika.westerberg@iki.fi>");
|
||||
MODULE_DESCRIPTION("TS-72xx SBC Watchdog");
|
||||
MODULE_LICENSE("GPL");
|
||||
MODULE_ALIAS("platform:ts72xx-wdt");
|
||||
Loading…
Reference in New Issue
Block a user