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Commit 8f5585ec authored by Paul Mundt's avatar Paul Mundt
Browse files

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: default avatarPaul Mundt <lethal@linux-sh.org>
parent b1fa888e

drivers/watchdog/shwdt.c

+168 −59
Original line number Diff line number Diff line
@@ -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;



struct sh_wdt {

	void __iomem		*base;

	struct device		*dev;



static void sh_wdt_start(void)

	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 @@ static void sh_wdt_start(void) 
	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 int sh_wdt_set_heartbeat(int t) 


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 @@ static void sh_wdt_ping(unsigned long data) 


		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 "

		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 "

		dev_crit(wdt->dev, "Unexpected close, not "

		         "stopping watchdog!\n");

		sh_wdt_keepalive();

		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 int sh_wdt_close(struct inode *inode, struct file *file) 
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 ssize_t sh_wdt_write(struct file *file, const char *buf, 
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 @@ static long sh_wdt_ioctl(struct file *file, unsigned int cmd, 
			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 @@ static long sh_wdt_ioctl(struct file *file, unsigned int cmd, 
		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 long sh_wdt_ioctl(struct file *file, unsigned int cmd, 
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 @@ static struct miscdevice sh_wdt_miscdev = { 
	.fops		= &sh_wdt_fops,

};



static int __init sh_wdt_init(void)

static int __devinit sh_wdt_probe(struct platform_device *pdev)

{

	struct sh_wdt *wdt;

	struct resource *res;

	int rc;



	if (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);

	/*

	 * 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;

	}



	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);

	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)) {

		printk(KERN_ERR PFX

		dev_err(&pdev->dev,

			"Can't register reboot notifier (err=%d)\n", rc);

		return rc;

		goto out_unmap;

	}



	sh_wdt_miscdev.parent = wdt->dev;



	rc = misc_register(&sh_wdt_miscdev);

	if (unlikely(rc)) {

		printk(KERN_ERR PFX

		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;

}



	printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",

		heartbeat, nowayout);

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 (unlikely(clock_division_ratio < 0x5 ||

		     clock_division_ratio > 0x7)) {

		clock_division_ratio = WTCSR_CKS_4096;



		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;



		pr_info("%s: heartbeat value must be 1<=x<=3600, using %d\n",

			DRV_NAME, heartbeat);

	}



	pr_info("%s: configured with heartbeat=%d sec (nowayout=%d)\n",

		DRV_NAME, heartbeat, nowayout);



	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_param(nowayout, int, 0); 
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);