[PATCH] hpet fixes

I eliminated the request_irq brain damage, chopped off procfs support
(didn't care for it too much in the first place and it was adopted from
rtc.c), made the check for FMODE_WRITE in hpet_open and responded to a few
other suggestions.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Documentation/devices.txt

@@ -434,6 +434,7 @@ Your cooperation is appreciated.
 		225 = /dev/pps		Pulse Per Second driver
 		226 = /dev/systrace	Systrace device
 		227 = /dev/mcelog	X86_64 Machine Check Exception driver
+		228 = /dev/hpet		HPET driver
 		240-254			Reserved for local use
 		255			Reserved for MISC_DYNAMIC_MINOR
 

Documentation/filesystems/proc.txt

@@ -201,7 +201,7 @@ Table 1-3: Kernel info in /proc
  devices     Available devices (block and character)           
  dma         Used DMS channels                                 
  filesystems Supported filesystems                             
- driver	     Various drivers grouped here, currently rtc (2.4) and hpet (2.6)
+ driver	     Various drivers grouped here, currently rtc (2.4)
  execdomains Execdomains, related to security			(2.4)
  fb	     Frame Buffer devices				(2.4)
  fs	     File system parameters, currently nfs/exports	(2.4)

Documentation/hpet.txt

@@ -103,7 +103,7 @@ hpet_open_close(int argc, const char **argv)
 		return;
 	}
 
-	fd = open(argv[0], O_RDWR);
+	fd = open(argv[0], O_RDONLY);
 	if (fd < 0)
 		fprintf(stderr, "hpet_open_close: open failed\n");
 	else
@@ -136,7 +136,7 @@ hpet_poll(int argc, const char **argv)
 	freq = atoi(argv[1]);
 	iterations = atoi(argv[2]);
 
-	fd = open(argv[0], O_RDWR);
+	fd = open(argv[0], O_RDONLY);
 
 	if (fd < 0) {
 		fprintf(stderr, "hpet_poll: open of %s failed\n", argv[0]);
@@ -230,7 +230,7 @@ hpet_fasync(int argc, const char **argv)
 		goto out;
 	}
 
-	fd = open(argv[0], O_RDWR);
+	fd = open(argv[0], O_RDONLY);
 
 	if (fd < 0) {
 		fprintf(stderr, "hpet_fasync: failed to open %s\n", argv[0]);

arch/i386/kernel/time_hpet.c

@@ -155,10 +155,9 @@ int __init hpet_enable(void)
 		hd.hd_address = hpet_virt_address;
 		hd.hd_nirqs = ntimer;
 		hd.hd_flags = HPET_DATA_PLATFORM;
-#ifndef	CONFIG_HPET_EMULATE_RTC
-		hd.hd_state = 0x1;
-#else
-		hd.hd_state = 0x3;
+		HD_STATE(&hd, 0);
+#ifdef	CONFIG_HPET_EMULATE_RTC
+		HD_STATE(&hd, 1);
 #endif
 		hd.hd_irq[0] = HPET_LEGACY_8254;
 		hd.hd_irq[1] = HPET_LEGACY_RTC;

drivers/char/hpet.c

@@ -50,6 +50,8 @@ static spinlock_t hpet_lock = SPIN_LOCK_UNLOCKED;
 /* A lock for concurrent intermodule access to hpet and isr hpet activity. */
 static spinlock_t hpet_task_lock = SPIN_LOCK_UNLOCKED;
 
+#define	HPET_DEV_NAME	(7)
+
 struct hpet_dev {
 	struct hpets *hd_hpets;
 	struct hpet *hd_hpet;
@@ -62,6 +64,7 @@ struct hpet_dev {
 	unsigned int hd_flags;
 	unsigned int hd_irq;
 	unsigned int hd_hdwirq;
+	char hd_name[HPET_DEV_NAME];
 };
 
 struct hpets {
@@ -148,6 +151,9 @@ static int hpet_open(struct inode *inode, struct file *file)
 	struct hpets *hpetp;
 	int i;
 
+	if (file->f_mode & FMODE_WRITE)
+		return -EINVAL;
+
 	spin_lock_irq(&hpet_lock);
 
 	for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next)
@@ -190,8 +196,8 @@ hpet_read(struct file *file, char __user *buf, size_t count, loff_t * ppos)
 
 	add_wait_queue(&devp->hd_waitqueue, &wait);
 
-	do {
-		__set_current_state(TASK_INTERRUPTIBLE);
+	for ( ; ; ) {
+		set_current_state(TASK_INTERRUPTIBLE);
 
 		spin_lock_irq(&hpet_lock);
 		data = devp->hd_irqdata;
@@ -207,16 +213,14 @@ hpet_read(struct file *file, char __user *buf, size_t count, loff_t * ppos)
 			retval = -ERESTARTSYS;
 			goto out;
 		}
-
 		schedule();
-
-	} while (1);
+	}
 
 	retval = put_user(data, (unsigned long __user *)buf);
 	if (!retval)
 		retval = sizeof(unsigned long);
-      out:
-	current->state = TASK_RUNNING;
+out:
+	__set_current_state(TASK_RUNNING);
 	remove_wait_queue(&devp->hd_waitqueue, &wait);
 
 	return retval;
@@ -255,9 +259,6 @@ static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
 	if (((vma->vm_end - vma->vm_start) != PAGE_SIZE) || vma->vm_pgoff)
 		return -EINVAL;
 
-	if (vma->vm_flags & VM_WRITE)
-		return -EPERM;
-
 	devp = file->private_data;
 	addr = (unsigned long)devp->hd_hpet;
 
@@ -371,12 +372,10 @@ static int hpet_ioctl_ieon(struct hpet_dev *devp)
 	irq = devp->hd_hdwirq;
 
 	if (irq) {
-		char name[7];
-
-		sprintf(name, "hpet%d", (int)(devp - hpetp->hp_dev));
+		sprintf(devp->hd_name, "hpet%d", (int)(devp - hpetp->hp_dev));
 
 		if (request_irq
-		    (irq, hpet_interrupt, SA_INTERRUPT, name, (void *)devp)) {
+		    (irq, hpet_interrupt, SA_INTERRUPT, devp->hd_name, (void *)devp)) {
 			printk(KERN_ERR "hpet: IRQ %d is not free\n", irq);
 			irq = 0;
 		}
@@ -731,73 +730,6 @@ static ctl_table dev_root[] = {
 
 static struct ctl_table_header *sysctl_header;
 
-static void *hpet_start(struct seq_file *s, loff_t * pos)
-{
-	struct hpets *hpetp;
-	loff_t n;
-
-	for (n = *pos, hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
-		if (!n--)
-			return hpetp;
-
-	return 0;
-}
-
-static void *hpet_next(struct seq_file *s, void *v, loff_t * pos)
-{
-	struct hpets *hpetp;
-
-	hpetp = v;
-	++*pos;
-	return hpetp->hp_next;
-}
-
-static void hpet_stop(struct seq_file *s, void *v)
-{
-	return;
-}
-
-static int hpet_show(struct seq_file *s, void *v)
-{
-	struct hpets *hpetp;
-	struct hpet *hpet;
-	u64 cap, vendor, period;
-
-	hpetp = v;
-	hpet = hpetp->hp_hpet;
-
-	cap = readq(&hpet->hpet_cap);
-	period = (cap & HPET_COUNTER_CLK_PERIOD_MASK) >>
-	    HPET_COUNTER_CLK_PERIOD_SHIFT;
-	vendor = (cap & HPET_VENDOR_ID_MASK) >> HPET_VENDOR_ID_SHIFT;
-
-	seq_printf(s,
-		   "HPET%d period = %d 10**-15  vendor = 0x%x number timer = %d\n",
-		   hpetp->hp_which, (u32) period, (u32) vendor,
-		   hpetp->hp_ntimer);
-
-	return 0;
-}
-
-static struct seq_operations hpet_seq_ops = {
-	.start = hpet_start,
-	.next = hpet_next,
-	.stop = hpet_stop,
-	.show = hpet_show
-};
-
-static int hpet_proc_open(struct inode *inode, struct file *file)
-{
-	return seq_open(file, &hpet_seq_ops);
-}
-
-static struct file_operations hpet_proc_fops = {
-	.open = hpet_proc_open,
-	.read = seq_read,
-	.llseek = seq_lseek,
-	.release = seq_release
-};
-
 /*
  * Adjustment for when arming the timer with
  * initial conditions.  That is, main counter
@@ -1025,19 +957,12 @@ static struct miscdevice hpet_misc = { HPET_MINOR, "hpet", &hpet_fops };
 
 static int __init hpet_init(void)
 {
-	struct proc_dir_entry *entry;
-
 	(void)acpi_bus_register_driver(&hpet_acpi_driver);
 
 	if (hpets) {
 		if (misc_register(&hpet_misc))
 			return -ENODEV;
 
-		entry = create_proc_entry("driver/hpet", 0, 0);
-
-		if (entry)
-			entry->proc_fops = &hpet_proc_fops;
-
 		sysctl_header = register_sysctl_table(dev_root, 0);
 
 #ifdef	CONFIG_TIME_INTERPOLATION
@@ -1062,10 +987,8 @@ static void __exit hpet_exit(void)
 {
 	acpi_bus_unregister_driver(&hpet_acpi_driver);
 
-	if (hpets) {
+	if (hpets)
 		unregister_sysctl_table(sysctl_header);
-		remove_proc_entry("driver/hpet", NULL);
-	}
 
 	return;
 }

include/linux/hpet.h

@@ -115,6 +115,8 @@ struct hpet_task {
 	void *ht_opaque;
 };
 
+#define	HD_STATE(HD, TIMER)	(HD)->hd_state |= (1 << TIMER)
+
 struct hpet_data {
 	unsigned long hd_address;
 	unsigned short hd_nirqs;

include/linux/miscdevice.h

@@ -33,9 +33,9 @@
 #define SGI_STREAMS_KEYBOARD 150
 /* drivers/sgi/char/usema.c */
 #define SGI_USEMACLONE	     151
-#define	HPET_MINOR	     152
 
 #define TUN_MINOR	     200
+#define	HPET_MINOR	     228
 
 struct device;