watchdog: shwdt: driver model conversion.
This is a long overdue driver model conversion for the shwdt watchdog
driver. This is the initial conversion, more incremental changes to
follow.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/drivers/watchdog/shwdt.c b/drivers/watchdog/shwdt.c
index bee1f58..b7d2f8a 100644
--- a/drivers/watchdog/shwdt.c
+++ b/drivers/watchdog/shwdt.c
@@ -19,6 +19,7 @@
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
+#include <linux/platform_device.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/miscdevice.h>
@@ -28,11 +29,12 @@
#include <linux/ioport.h>
#include <linux/fs.h>
#include <linux/mm.h>
+#include <linux/slab.h>
#include <linux/io.h>
#include <linux/uaccess.h>
#include <asm/watchdog.h>
-#define PFX "shwdt: "
+#define DRV_NAME "sh-wdt"
/*
* Default clock division ratio is 5.25 msecs. For an additional table of
@@ -62,31 +64,36 @@
* misses its deadline, the kernel timer will allow the WDT to overflow.
*/
static int clock_division_ratio = WTCSR_CKS_4096;
-
#define next_ping_period(cks) msecs_to_jiffies(cks - 4)
-static void sh_wdt_ping(unsigned long data);
-
-static unsigned long shwdt_is_open;
static const struct watchdog_info sh_wdt_info;
-static char shwdt_expect_close;
-static DEFINE_TIMER(timer, sh_wdt_ping, 0, 0);
-static unsigned long next_heartbeat;
+static struct platform_device *sh_wdt_dev;
static DEFINE_SPINLOCK(shwdt_lock);
#define WATCHDOG_HEARTBEAT 30 /* 30 sec default heartbeat */
static int heartbeat = WATCHDOG_HEARTBEAT; /* in seconds */
static int nowayout = WATCHDOG_NOWAYOUT;
+static unsigned long next_heartbeat;
-static void sh_wdt_start(void)
+struct sh_wdt {
+ void __iomem *base;
+ struct device *dev;
+
+ struct timer_list timer;
+
+ unsigned long enabled;
+ char expect_close;
+};
+
+static void sh_wdt_start(struct sh_wdt *wdt)
{
- __u8 csr;
unsigned long flags;
+ u8 csr;
spin_lock_irqsave(&shwdt_lock, flags);
next_heartbeat = jiffies + (heartbeat * HZ);
- mod_timer(&timer, next_ping_period(clock_division_ratio));
+ mod_timer(&wdt->timer, next_ping_period(clock_division_ratio));
csr = sh_wdt_read_csr();
csr |= WTCSR_WT | clock_division_ratio;
@@ -115,22 +122,23 @@
spin_unlock_irqrestore(&shwdt_lock, flags);
}
-static void sh_wdt_stop(void)
+static void sh_wdt_stop(struct sh_wdt *wdt)
{
- __u8 csr;
unsigned long flags;
+ u8 csr;
spin_lock_irqsave(&shwdt_lock, flags);
- del_timer(&timer);
+ del_timer(&wdt->timer);
csr = sh_wdt_read_csr();
csr &= ~WTCSR_TME;
sh_wdt_write_csr(csr);
+
spin_unlock_irqrestore(&shwdt_lock, flags);
}
-static inline void sh_wdt_keepalive(void)
+static inline void sh_wdt_keepalive(struct sh_wdt *wdt)
{
unsigned long flags;
@@ -154,11 +162,12 @@
static void sh_wdt_ping(unsigned long data)
{
+ struct sh_wdt *wdt = (struct sh_wdt *)data;
unsigned long flags;
spin_lock_irqsave(&shwdt_lock, flags);
if (time_before(jiffies, next_heartbeat)) {
- __u8 csr;
+ u8 csr;
csr = sh_wdt_read_csr();
csr &= ~WTCSR_IOVF;
@@ -166,37 +175,43 @@
sh_wdt_write_cnt(0);
- mod_timer(&timer, next_ping_period(clock_division_ratio));
+ mod_timer(&wdt->timer, next_ping_period(clock_division_ratio));
} else
- printk(KERN_WARNING PFX "Heartbeat lost! Will not ping "
- "the watchdog\n");
+ dev_warn(wdt->dev, "Heartbeat lost! Will not ping "
+ "the watchdog\n");
spin_unlock_irqrestore(&shwdt_lock, flags);
}
static int sh_wdt_open(struct inode *inode, struct file *file)
{
- if (test_and_set_bit(0, &shwdt_is_open))
+ struct sh_wdt *wdt = platform_get_drvdata(sh_wdt_dev);
+
+ if (test_and_set_bit(0, &wdt->enabled))
return -EBUSY;
if (nowayout)
__module_get(THIS_MODULE);
- sh_wdt_start();
+ file->private_data = wdt;
+
+ sh_wdt_start(wdt);
return nonseekable_open(inode, file);
}
static int sh_wdt_close(struct inode *inode, struct file *file)
{
- if (shwdt_expect_close == 42) {
- sh_wdt_stop();
+ struct sh_wdt *wdt = file->private_data;
+
+ if (wdt->expect_close == 42) {
+ sh_wdt_stop(wdt);
} else {
- printk(KERN_CRIT PFX "Unexpected close, not "
- "stopping watchdog!\n");
- sh_wdt_keepalive();
+ dev_crit(wdt->dev, "Unexpected close, not "
+ "stopping watchdog!\n");
+ sh_wdt_keepalive(wdt);
}
- clear_bit(0, &shwdt_is_open);
- shwdt_expect_close = 0;
+ clear_bit(0, &wdt->enabled);
+ wdt->expect_close = 0;
return 0;
}
@@ -204,21 +219,23 @@
static ssize_t sh_wdt_write(struct file *file, const char *buf,
size_t count, loff_t *ppos)
{
+ struct sh_wdt *wdt = file->private_data;
+
if (count) {
if (!nowayout) {
size_t i;
- shwdt_expect_close = 0;
+ wdt->expect_close = 0;
for (i = 0; i != count; i++) {
char c;
if (get_user(c, buf + i))
return -EFAULT;
if (c == 'V')
- shwdt_expect_close = 42;
+ wdt->expect_close = 42;
}
}
- sh_wdt_keepalive();
+ sh_wdt_keepalive(wdt);
}
return count;
@@ -227,6 +244,7 @@
static long sh_wdt_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
+ struct sh_wdt *wdt = file->private_data;
int new_heartbeat;
int options, retval = -EINVAL;
@@ -242,18 +260,18 @@
return -EFAULT;
if (options & WDIOS_DISABLECARD) {
- sh_wdt_stop();
+ sh_wdt_stop(wdt);
retval = 0;
}
if (options & WDIOS_ENABLECARD) {
- sh_wdt_start();
+ sh_wdt_start(wdt);
retval = 0;
}
return retval;
case WDIOC_KEEPALIVE:
- sh_wdt_keepalive();
+ sh_wdt_keepalive(wdt);
return 0;
case WDIOC_SETTIMEOUT:
if (get_user(new_heartbeat, (int *)arg))
@@ -262,7 +280,7 @@
if (sh_wdt_set_heartbeat(new_heartbeat))
return -EINVAL;
- sh_wdt_keepalive();
+ sh_wdt_keepalive(wdt);
/* Fall */
case WDIOC_GETTIMEOUT:
return put_user(heartbeat, (int *)arg);
@@ -275,8 +293,10 @@
static int sh_wdt_notify_sys(struct notifier_block *this,
unsigned long code, void *unused)
{
+ struct sh_wdt *wdt = platform_get_drvdata(sh_wdt_dev);
+
if (code == SYS_DOWN || code == SYS_HALT)
- sh_wdt_stop();
+ sh_wdt_stop(wdt);
return NOTIFY_DONE;
}
@@ -307,56 +327,148 @@
.fops = &sh_wdt_fops,
};
+static int __devinit sh_wdt_probe(struct platform_device *pdev)
+{
+ struct sh_wdt *wdt;
+ struct resource *res;
+ int rc;
+
+ /*
+ * As this driver only covers the global watchdog case, reject
+ * any attempts to register per-CPU watchdogs.
+ */
+ if (pdev->id != -1)
+ return -EINVAL;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (unlikely(!res))
+ return -EINVAL;
+
+ if (!devm_request_mem_region(&pdev->dev, res->start,
+ resource_size(res), DRV_NAME))
+ return -EBUSY;
+
+ wdt = devm_kzalloc(&pdev->dev, sizeof(struct sh_wdt), GFP_KERNEL);
+ if (unlikely(!wdt)) {
+ rc = -ENOMEM;
+ goto out_release;
+ }
+
+ wdt->dev = &pdev->dev;
+
+ wdt->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
+ if (unlikely(!wdt->base)) {
+ rc = -ENXIO;
+ goto out_err;
+ }
+
+ rc = register_reboot_notifier(&sh_wdt_notifier);
+ if (unlikely(rc)) {
+ dev_err(&pdev->dev,
+ "Can't register reboot notifier (err=%d)\n", rc);
+ goto out_unmap;
+ }
+
+ sh_wdt_miscdev.parent = wdt->dev;
+
+ rc = misc_register(&sh_wdt_miscdev);
+ if (unlikely(rc)) {
+ dev_err(&pdev->dev,
+ "Can't register miscdev on minor=%d (err=%d)\n",
+ sh_wdt_miscdev.minor, rc);
+ goto out_unreg;
+ }
+
+ init_timer(&wdt->timer);
+ wdt->timer.function = sh_wdt_ping;
+ wdt->timer.data = (unsigned long)wdt;
+ wdt->timer.expires = next_ping_period(clock_division_ratio);
+
+ platform_set_drvdata(pdev, wdt);
+ sh_wdt_dev = pdev;
+
+ dev_info(&pdev->dev, "initialized.\n");
+
+ return 0;
+
+out_unreg:
+ unregister_reboot_notifier(&sh_wdt_notifier);
+out_unmap:
+ devm_iounmap(&pdev->dev, wdt->base);
+out_err:
+ devm_kfree(&pdev->dev, wdt);
+out_release:
+ devm_release_mem_region(&pdev->dev, res->start, resource_size(res));
+
+ return rc;
+}
+
+static int __devexit sh_wdt_remove(struct platform_device *pdev)
+{
+ struct sh_wdt *wdt = platform_get_drvdata(pdev);
+ struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+ platform_set_drvdata(pdev, NULL);
+
+ misc_deregister(&sh_wdt_miscdev);
+
+ sh_wdt_dev = NULL;
+
+ unregister_reboot_notifier(&sh_wdt_notifier);
+ devm_release_mem_region(&pdev->dev, res->start, resource_size(res));
+ devm_iounmap(&pdev->dev, wdt->base);
+ devm_kfree(&pdev->dev, wdt);
+
+ return 0;
+}
+
+static struct platform_driver sh_wdt_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ .owner = THIS_MODULE,
+ },
+
+ .probe = sh_wdt_probe,
+ .remove = __devexit_p(sh_wdt_remove),
+};
+
static int __init sh_wdt_init(void)
{
int rc;
- if (clock_division_ratio < 0x5 || clock_division_ratio > 0x7) {
+ if (unlikely(clock_division_ratio < 0x5 ||
+ clock_division_ratio > 0x7)) {
clock_division_ratio = WTCSR_CKS_4096;
- printk(KERN_INFO PFX
- "clock_division_ratio value must be 0x5<=x<=0x7, using %d\n",
- clock_division_ratio);
+
+ pr_info("%s: divisor must be 0x5<=x<=0x7, using %d\n",
+ DRV_NAME, clock_division_ratio);
}
rc = sh_wdt_set_heartbeat(heartbeat);
if (unlikely(rc)) {
heartbeat = WATCHDOG_HEARTBEAT;
- printk(KERN_INFO PFX
- "heartbeat value must be 1<=x<=3600, using %d\n",
- heartbeat);
+
+ pr_info("%s: heartbeat value must be 1<=x<=3600, using %d\n",
+ DRV_NAME, heartbeat);
}
- rc = register_reboot_notifier(&sh_wdt_notifier);
- if (unlikely(rc)) {
- printk(KERN_ERR PFX
- "Can't register reboot notifier (err=%d)\n", rc);
- return rc;
- }
+ pr_info("%s: configured with heartbeat=%d sec (nowayout=%d)\n",
+ DRV_NAME, heartbeat, nowayout);
- rc = misc_register(&sh_wdt_miscdev);
- if (unlikely(rc)) {
- printk(KERN_ERR PFX
- "Can't register miscdev on minor=%d (err=%d)\n",
- sh_wdt_miscdev.minor, rc);
- unregister_reboot_notifier(&sh_wdt_notifier);
- return rc;
- }
-
- printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
- heartbeat, nowayout);
-
- return 0;
+ return platform_driver_register(&sh_wdt_driver);
}
static void __exit sh_wdt_exit(void)
{
- misc_deregister(&sh_wdt_miscdev);
- unregister_reboot_notifier(&sh_wdt_notifier);
+ platform_driver_unregister(&sh_wdt_driver);
}
+module_init(sh_wdt_init);
+module_exit(sh_wdt_exit);
MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
MODULE_DESCRIPTION("SuperH watchdog driver");
MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRV_NAME);
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
module_param(clock_division_ratio, int, 0);
@@ -373,6 +485,3 @@
MODULE_PARM_DESC(nowayout,
"Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
-
-module_init(sh_wdt_init);
-module_exit(sh_wdt_exit);