[WATCHDOG 42/57] sc1200_wdt: clean up, fix locking and use unlocked_ioctl (d14bccaa) · Commits · e / devices / android_kernel_xiaomi_markw

drivers/watchdog/sc1200wdt.c

+114 −89

Original line number	Diff line number	Diff line
		@@ -15,14 +15,18 @@
		*
		* Changelog:
		* 20020220 Zwane Mwaikambo Code based on datasheet, no hardware.
		* 20020221 Zwane Mwaikambo Cleanups as suggested by Jeff Garzik and Alan Cox.
		* 20020221 Zwane Mwaikambo Cleanups as suggested by Jeff Garzik
		* and Alan Cox.
		* 20020222 Zwane Mwaikambo Added probing.
		* 20020225 Zwane Mwaikambo Added ISAPNP support.
		* 20020412 Rob Radez Broke out start/stop functions
		* <rob@osinvestor.com> Return proper status instead of temperature warning
		* Add WDIOC_GETBOOTSTATUS and WDIOC_SETOPTIONS ioctls
		* <rob@osinvestor.com> Return proper status instead of
		* temperature warning
		* Add WDIOC_GETBOOTSTATUS and
		* WDIOC_SETOPTIONS ioctls
		* Fix CONFIG_WATCHDOG_NOWAYOUT
		* 20020530 Joel Becker Add Matt Domsch's nowayout module option
		* 20020530 Joel Becker Add Matt Domsch's nowayout module
		* option
		* 20030116 Adam Belay Updated to the latest pnp code
		*
		*/
		@@ -39,9 +43,8 @@
		#include <linux/pnp.h>
		#include <linux/fs.h>
		#include <linux/semaphore.h>

		#include <asm/io.h>
		#include <asm/uaccess.h>
		#include <linux/io.h>
		#include <linux/uaccess.h>

		#define SC1200_MODULE_VER "build 20020303"
		#define SC1200_MODULE_NAME "sc1200wdt"
		@@ -72,7 +75,7 @@ static char banner[] __initdata = KERN_INFO PFX SC1200_MODULE_VER;
		static int timeout = 1;
		static int io = -1;
		static int io_len = 2; /* for non plug and play */
		static struct semaphore open_sem;
		static unsigned long open_flag;
		static char expect_close;
		static DEFINE_SPINLOCK(sc1200wdt_lock); /* io port access serialisation */

		@@ -81,7 +84,8 @@ static int isapnp = 1;
		static struct pnp_dev *wdt_dev;

		module_param(isapnp, int, 0);
		MODULE_PARM_DESC(isapnp, "When set to 0 driver ISA PnP support will be disabled");
		MODULE_PARM_DESC(isapnp,
		"When set to 0 driver ISA PnP support will be disabled");
		#endif

		module_param(io, int, 0);
		@@ -91,26 +95,40 @@ MODULE_PARM_DESC(timeout, "range is 0-255 minutes, default is 1");

		static int nowayout = WATCHDOG_NOWAYOUT;
		module_param(nowayout, int, 0);
		MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
		MODULE_PARM_DESC(nowayout,
		"Watchdog cannot be stopped once started (default="
		__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");



		/* Read from Data Register */
		static inline void sc1200wdt_read_data(unsigned char index, unsigned char *data)
		static inline void __sc1200wdt_read_data(unsigned char index,
		unsigned char *data)
		{
		spin_lock(&sc1200wdt_lock);
		outb_p(index, PMIR);
		*data = inb(PMDR);
		spin_unlock(&sc1200wdt_lock);
		}

		static void sc1200wdt_read_data(unsigned char index, unsigned char *data)
		{
		spin_lock(&sc1200wdt_lock);
		__sc1200wdt_read_data(index, data);
		spin_unlock(&sc1200wdt_lock);
		}

		/* Write to Data Register */
		static inline void sc1200wdt_write_data(unsigned char index, unsigned char data)
		static inline void __sc1200wdt_write_data(unsigned char index,
		unsigned char data)
		{
		spin_lock(&sc1200wdt_lock);
		outb_p(index, PMIR);
		outb(data, PMDR);
		}

		static inline void sc1200wdt_write_data(unsigned char index,
		unsigned char data)
		{
		spin_lock(&sc1200wdt_lock);
		__sc1200wdt_write_data(index, data);
		spin_unlock(&sc1200wdt_lock);
		}

		@@ -118,13 +136,16 @@ static inline void sc1200wdt_write_data(unsigned char index, unsigned char data)
		static void sc1200wdt_start(void)
		{
		unsigned char reg;
		spin_lock(&sc1200wdt_lock);

		sc1200wdt_read_data(WDCF, &reg);
		__sc1200wdt_read_data(WDCF, &reg);
		/* assert WDO when any of the following interrupts are triggered too */
		reg \|= (KBC_IRQ \| MSE_IRQ \| UART1_IRQ \| UART2_IRQ);
		sc1200wdt_write_data(WDCF, reg);
		__sc1200wdt_write_data(WDCF, reg);
		/* set the timeout and get the ball rolling */
		sc1200wdt_write_data(WDTO, timeout);
		__sc1200wdt_write_data(WDTO, timeout);

		spin_unlock(&sc1200wdt_lock);
		}


		@@ -144,14 +165,15 @@ static inline int sc1200wdt_status(void)
		* KEEPALIVEPING which is a bit of a kludge because there's nothing
		* else for enabled/disabled status
		*/
		return (ret & 0x01) ? 0 : WDIOF_KEEPALIVEPING; /* bits 1 - 7 are undefined */
		return (ret & 0x01) ? 0 : WDIOF_KEEPALIVEPING;
		/* bits 1 - 7 are undefined */
		}


		static int sc1200wdt_open(struct inode inode, struct file file)
		{
		/* allow one at a time */
		if (down_trylock(&open_sem))
		if (test_and_set_bit(0, &open_flag))
		return -EBUSY;

		if (timeout > MAX_TIMEOUT)
		@@ -164,20 +186,20 @@ static int sc1200wdt_open(struct inode inode, struct file file)
		}


		static int sc1200wdt_ioctl(struct inode inode, struct file file, unsigned int cmd, unsigned long arg)
		static long sc1200wdt_ioctl(struct file *file, unsigned int cmd,
		unsigned long arg)
		{
		int new_timeout;
		void __user argp = (void __user )arg;
		int __user *p = argp;
		static struct watchdog_info ident = {
		.options = WDIOF_KEEPALIVEPING \| WDIOF_SETTIMEOUT \| WDIOF_MAGICCLOSE,
		static const struct watchdog_info ident = {
		.options = WDIOF_KEEPALIVEPING \| WDIOF_SETTIMEOUT \|
		WDIOF_MAGICCLOSE,
		.firmware_version = 0,
		.identity = "PC87307/PC97307",
		};

		switch (cmd) {
		default:
		return -ENOTTY;

		case WDIOC_GETSUPPORT:
		if (copy_to_user(argp, &ident, sizeof ident))
		@@ -197,12 +219,10 @@ static int sc1200wdt_ioctl(struct inode inode, struct file file, unsigned int
		case WDIOC_SETTIMEOUT:
		if (get_user(new_timeout, p))
		return -EFAULT;

		/* the API states this is given in secs */
		new_timeout /= 60;
		if (new_timeout < 0 \|\| new_timeout > MAX_TIMEOUT)
		return -EINVAL;

		timeout = new_timeout;
		sc1200wdt_write_data(WDTO, timeout);
		/* fall through and return the new timeout */
		@@ -229,6 +249,8 @@ static int sc1200wdt_ioctl(struct inode inode, struct file file, unsigned int

		return retval;
		}
		default:
		return -ENOTTY;
		}
		}

		@@ -240,16 +262,18 @@ static int sc1200wdt_release(struct inode inode, struct file file)
		printk(KERN_INFO PFX "Watchdog disabled\n");
		} else {
		sc1200wdt_write_data(WDTO, timeout);
		printk(KERN_CRIT PFX "Unexpected close!, timeout = %d min(s)\n", timeout);
		printk(KERN_CRIT PFX
		"Unexpected close!, timeout = %d min(s)\n", timeout);
		}
		up(&open_sem);
		clear_bit(0, &open_flag);
		expect_close = 0;

		return 0;
		}


		static ssize_t sc1200wdt_write(struct file file, const char __user data, size_t len, loff_t *ppos)
		static ssize_t sc1200wdt_write(struct file file, const char __user data,
		size_t len, loff_t *ppos)
		{
		if (len) {
		if (!nowayout) {
		@@ -275,7 +299,8 @@ static ssize_t sc1200wdt_write(struct file file, const char __user data, size_
		}


		static int sc1200wdt_notify_sys(struct notifier_block this, unsigned long code, void unused)
		static int sc1200wdt_notify_sys(struct notifier_block *this,
		unsigned long code, void *unused)
		{
		if (code == SYS_DOWN \|\| code == SYS_HALT)
		sc1200wdt_stop();
		@@ -284,23 +309,20 @@ static int sc1200wdt_notify_sys(struct notifier_block *this, unsigned long code,
		}


		static struct notifier_block sc1200wdt_notifier =
		{
		static struct notifier_block sc1200wdt_notifier = {
		.notifier_call = sc1200wdt_notify_sys,
		};

		static const struct file_operations sc1200wdt_fops =
		{
		static const struct file_operations sc1200wdt_fops = {
		.owner = THIS_MODULE,
		.llseek = no_llseek,
		.write = sc1200wdt_write,
		.ioctl = sc1200wdt_ioctl,
		.unlocked_ioctl = sc1200wdt_ioctl,
		.open = sc1200wdt_open,
		.release = sc1200wdt_release,
		};

		static struct miscdevice sc1200wdt_miscdev =
		{
		static struct miscdevice sc1200wdt_miscdev = {
		.minor = WATCHDOG_MINOR,
		.name = "watchdog",
		.fops = &sc1200wdt_fops,
		@@ -312,8 +334,8 @@ static int __init sc1200wdt_probe(void)
		/* The probe works by reading the PMC3 register's default value of 0x0e
		* there is one caveat, if the device disables the parallel port or any
		* of the UARTs we won't be able to detect it.
		* Nb. This could be done with accuracy by reading the SID registers, but
		* we don't have access to those io regions.
		* NB. This could be done with accuracy by reading the SID registers,
		* but we don't have access to those io regions.
		*/

		unsigned char reg;
		@@ -332,7 +354,8 @@ static struct pnp_device_id scl200wdt_pnp_devices[] = {
		{.id = ""},
		};

		static int scl200wdt_pnp_probe(struct pnp_dev * dev, const struct pnp_device_id *dev_id)
		static int scl200wdt_pnp_probe(struct pnp_dev *dev,
		const struct pnp_device_id *dev_id)
		{
		/* this driver only supports one card at a time */
		if (wdt_dev \|\| !isapnp)
		@@ -347,7 +370,8 @@ static int scl200wdt_pnp_probe(struct pnp_dev * dev, const struct pnp_device_id
		return -EBUSY;
		}

		printk(KERN_INFO "scl200wdt: PnP device found at io port %#x/%d\n", io, io_len);
		printk(KERN_INFO "scl200wdt: PnP device found at io port %#x/%d\n",
		io, io_len);
		return 0;
		}

		@@ -375,8 +399,6 @@ static int __init sc1200wdt_init(void)

		printk("%s\n", banner);

		sema_init(&open_sem, 1);

		#if defined CONFIG_PNP
		if (isapnp) {
		ret = pnp_register_driver(&scl200wdt_pnp_driver);
		@@ -410,13 +432,16 @@ static int __init sc1200wdt_init(void)

		ret = register_reboot_notifier(&sc1200wdt_notifier);
		if (ret) {
		printk(KERN_ERR PFX "Unable to register reboot notifier err = %d\n", ret);
		printk(KERN_ERR PFX
		"Unable to register reboot notifier err = %d\n", ret);
		goto out_io;
		}

		ret = misc_register(&sc1200wdt_miscdev);
		if (ret) {
		printk(KERN_ERR PFX "Unable to register miscdev on minor %d\n", WATCHDOG_MINOR);
		printk(KERN_ERR PFX
		"Unable to register miscdev on minor %d\n",
		WATCHDOG_MINOR);
		goto out_rbt;
		}