[PATCH] mmtimer cleanups
From: Jesse Barnes
Date: Fri Sep 17 2004 - 15:17:09 EST
A few cleanups that probably should have been done a long time ago:
o remove test program from mmtimer.h
o move name, desc., etc. #defines from mmtimer.h to mmtimer.c
o document what mmtimer.c is a little better
o some whitespace cleanups for linewrapping and such
Signed-off-by: Jesse Barnes <jbarnes@xxxxxxx>
Thanks,
Jesse
===== drivers/char/mmtimer.c 1.1 vs edited =====
--- 1.1/drivers/char/mmtimer.c 2004-09-17 00:07:01 -07:00
+++ edited/drivers/char/mmtimer.c 2004-09-17 13:03:11 -07:00
@@ -5,10 +5,11 @@
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
- * Copyright (c) 2001-2003 Silicon Graphics, Inc. All rights reserved.
+ * Copyright (c) 2001-2004 Silicon Graphics, Inc. All rights reserved.
*
- * This driver implements a subset of the interface required by the
- * IA-PC Multimedia Timers Draft Specification (rev. 0.97) from Intel.
+ * This driver exports an API that should be supportable by any HPET or IA-PC
+ * multimedia timer. The code below is currently specific to the SGI Altix
+ * SHub RTC, however.
*
* 11/01/01 - jbarnes - initial revision
* 9/10/04 - Christoph Lameter - remove interrupt support for kernel inclusion
@@ -32,9 +33,16 @@
MODULE_DESCRIPTION("Multimedia timer support");
MODULE_LICENSE("GPL");
+/* name of the device, usually in /dev */
+#define MMTIMER_NAME "mmtimer"
+#define MMTIMER_FULLNAME "/dev/mmtimer"
+#define MMTIMER_DESC "IA-PC Multimedia Timer"
+#define MMTIMER_VERSION "1.0"
+
#define RTC_BITS 55 /* 55 bits for this implementation */
-static int mmtimer_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
+static int mmtimer_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg);
static int mmtimer_mmap(struct file *file, struct vm_area_struct *vma);
/*
@@ -55,8 +63,10 @@
* @cmd: command to execute
* @arg: optional argument to command
*
- * Executes the command specified by @cmd. Returns 0 for success, <0 for failure.
- * Valid commands are
+ * Executes the command specified by @cmd. Returns 0 for success, < 0 for
+ * failure.
+ *
+ * Valid commands:
*
* %MMTIMER_GETOFFSET - Should return the offset (relative to the start
* of the page where the registers are mapped) for the counter in question.
@@ -74,8 +84,8 @@
* %MMTIMER_GETCOUNTER - Gets the current value in the counter and places it
* in the address specified by @arg.
*/
-static int
-mmtimer_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
+static int mmtimer_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
{
int ret = 0;
@@ -91,12 +101,15 @@
break;
case MMTIMER_GETRES: /* resolution of the clock in 10^-15 s */
- if(copy_to_user((unsigned long *)arg, &mmtimer_femtoperiod, sizeof(unsigned long)))
+ if(copy_to_user((unsigned long *)arg, &mmtimer_femtoperiod,
+ sizeof(unsigned long)))
return -EFAULT;
break;
case MMTIMER_GETFREQ: /* frequency in Hz */
- if(copy_to_user((unsigned long *)arg, &sn_rtc_cycles_per_second, sizeof(unsigned long)))
+ if(copy_to_user((unsigned long *)arg,
+ &sn_rtc_cycles_per_second,
+ sizeof(unsigned long)))
return -EFAULT;
ret = 0;
break;
@@ -110,7 +123,8 @@
break;
case MMTIMER_GETCOUNTER:
- if(copy_to_user((unsigned long *)arg, RTC_COUNTER_ADDR, sizeof(unsigned long)))
+ if(copy_to_user((unsigned long *)arg, RTC_COUNTER_ADDR,
+ sizeof(unsigned long)))
return -EFAULT;
break;
default:
@@ -129,8 +143,7 @@
* Calls remap_page_range() to map the clock's registers into
* the calling process' address space.
*/
-static int
-mmtimer_mmap(struct file *file, struct vm_area_struct *vma)
+static int mmtimer_mmap(struct file *file, struct vm_area_struct *vma)
{
unsigned long mmtimer_addr;
@@ -150,7 +163,8 @@
mmtimer_addr &= ~(PAGE_SIZE - 1);
mmtimer_addr &= 0xfffffffffffffffUL;
- if (remap_page_range(vma, vma->vm_start, mmtimer_addr, PAGE_SIZE, vma->vm_page_prot)) {
+ if (remap_page_range(vma, vma->vm_start, mmtimer_addr, PAGE_SIZE,
+ vma->vm_page_prot)) {
printk(KERN_ERR "remap_page_range failed in mmtimer.c\n");
return -EAGAIN;
}
@@ -169,27 +183,29 @@
*
* Does initial setup for the mmtimer device.
*/
-static int __init
-mmtimer_init(void)
+static int __init mmtimer_init(void)
{
/*
* Sanity check the cycles/sec variable
*/
if (sn_rtc_cycles_per_second < 100000) {
- printk(KERN_ERR "%s: unable to determine clock frequency\n", MMTIMER_NAME);
+ printk(KERN_ERR "%s: unable to determine clock frequency\n",
+ MMTIMER_NAME);
return -1;
}
- mmtimer_femtoperiod = ((unsigned long)1E15 + sn_rtc_cycles_per_second / 2) /
- sn_rtc_cycles_per_second;
+ mmtimer_femtoperiod = ((unsigned long)1E15 + sn_rtc_cycles_per_second /
+ 2) / sn_rtc_cycles_per_second;
strcpy(mmtimer_miscdev.devfs_name, MMTIMER_NAME);
if (misc_register(&mmtimer_miscdev)) {
- printk(KERN_ERR "%s: failed to register device\n", MMTIMER_NAME);
+ printk(KERN_ERR "%s: failed to register device\n",
+ MMTIMER_NAME);
return -1;
}
- printk(KERN_INFO "%s: v%s, %ld MHz\n", MMTIMER_DESC, MMTIMER_VERSION, sn_rtc_cycles_per_second/(unsigned long)1E6);
+ printk(KERN_INFO "%s: v%s, %ld MHz\n", MMTIMER_DESC, MMTIMER_VERSION,
+ sn_rtc_cycles_per_second/(unsigned long)1E6);
return 0;
}
===== include/linux/mmtimer.h 1.1 vs edited =====
--- 1.1/include/linux/mmtimer.h 2004-09-17 00:07:01 -07:00
+++ edited/include/linux/mmtimer.h 2004-09-17 13:03:44 -07:00
@@ -5,7 +5,7 @@
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
- * Copyright (c) 2001-2003 Silicon Graphics, Inc. All rights reserved.
+ * Copyright (c) 2001-2004 Silicon Graphics, Inc. All rights reserved.
*
* This file should define an interface compatible with the IA-PC Multimedia
* Timers Draft Specification (rev. 0.97) from Intel. Note that some
@@ -14,17 +14,12 @@
*
* 11/01/01 - jbarnes - initial revision
* 9/10/04 - Christoph Lameter - remove interrupt support
+ * 9/17/04 - jbarnes - remove test program, move some #defines to the driver
*/
#ifndef _LINUX_MMTIMER_H
#define _LINUX_MMTIMER_H
-/* name of the device, usually in /dev */
-#define MMTIMER_NAME "mmtimer"
-#define MMTIMER_FULLNAME "/dev/mmtimer"
-#define MMTIMER_DESC "IA-PC Multimedia Timer"
-#define MMTIMER_VERSION "1.0"
-
/*
* Breakdown of the ioctl's available. An 'optional' next to the command
* indicates that supporting this command is optional, while 'required'
@@ -57,84 +52,5 @@
#define MMTIMER_GETBITS _IO(MMTIMER_IOCTL_BASE, 4)
#define MMTIMER_MMAPAVAIL _IO(MMTIMER_IOCTL_BASE, 6)
#define MMTIMER_GETCOUNTER _IOR(MMTIMER_IOCTL_BASE, 9, unsigned long)
-
-/*
- * An mmtimer verification program. WARNINGs are ok, but ERRORs indicate
- * that the device doesn't fully support the interface defined here.
- */
-#ifdef _MMTIMER_TEST_PROGRAM
-
-#include <stdio.h>
-#include <unistd.h>
-#include <errno.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-
-#include <sys/ioctl.h>
-
-#include "mmtimer.h"
-
-int main(int argc, char *argv[])
-{
- int result, fd;
- unsigned long val = 0;
- unsigned long i;
-
- if((fd = open("/dev/"MMTIMER_NAME, O_RDONLY)) == -1) {
- printf("failed to open /dev/%s", MMTIMER_NAME);
- return 1;
- }
-
- /*
- * Can we mmap in the counter?
- */
- if((result = ioctl(fd, MMTIMER_MMAPAVAIL, 0)) == 1) {
- printf("mmap available\n");
- /* ... so try getting the offset for each clock */
- if((result = ioctl(fd, MMTIMER_GETOFFSET, 0)) != -ENOSYS)
- printf("offset: %d\n", result);
- else
- printf("WARNING: offset unavailable for clock\n");
- }
- else
- printf("WARNING: mmap unavailable\n");
-
- /*
- * Get the resolution in femtoseconds
- */
- if((result = ioctl(fd, MMTIMER_GETRES, &val)) != -ENOSYS)
- printf("resolution: %ld femtoseconds\n", val);
- else
- printf("ERROR: failed to get resolution\n");
-
- /*
- * Get the frequency in Hz
- */
- if((result = ioctl(fd, MMTIMER_GETFREQ, &val)) != -ENOSYS)
- if(val < 10000000) /* less than 10 MHz? */
- printf("ERROR: frequency only %ld MHz, should be >= 10 MHz\n", val/1000000);
- else
- printf("frequency: %ld MHz\n", val/1000000);
- else
- printf("ERROR: failed to get frequency\n");
-
- /*
- * How many bits in the counter?
- */
- if((result = ioctl(fd, MMTIMER_GETBITS, 0)) != -ENOSYS)
- printf("bits in counter: %d\n", result);
- else
- printf("ERROR: can't get number of bits in counter\n");
-
- if((result = ioctl(fd, MMTIMER_GETCOUNTER, &val)) != -ENOSYS)
- printf("counter value: %ld\n", val);
- else
- printf("ERROR: can't get counter value\n");
-
- return 0;
-}
-
-#endif /* _MMTIMER_TEST_PROGRM */
#endif /* _LINUX_MMTIMER_H */