Commit b1f3bb49 authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Geert Uytterhoeven
Browse files

m68k: Remove BKL from rtc implementations 



m68k does not support SMP. The access to the rtc is already serialized
with local_irq_save/restore which is sufficient on UP.

The open() protection in arch/m68k/mvme16x/rtc.c is not pretty but
sufficient on UP and safe w/o the BKL.

open() in arch/m68k/bvme6000/rtc.c can do with the same atomic logic
as arch/m68k/mvme16x/rtc.c

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
parent e40152ee

arch/m68k/bvme6000/rtc.c

+9 −20
Original line number Diff line number Diff line
@@ -9,7 +9,6 @@ 
#include <linux/types.h>

#include <linux/errno.h>

#include <linux/miscdevice.h>

#include <linux/smp_lock.h>

#include <linux/ioport.h>

#include <linux/capability.h>

#include <linux/fcntl.h>
@@ -35,10 +34,9 @@ 
static unsigned char days_in_mo[] =

{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};



static char rtc_status;

static atomic_t rtc_status = ATOMIC_INIT(1);



static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,

		     unsigned long arg)

static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)

{

	volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;

	unsigned char msr;
@@ -133,28 +131,19 @@ static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd, 


/*

 * We enforce only one user at a time here with the open/close.

 *	Also clear the previous interrupt data on an open, and clean

 *	up things on a close.

 */



static int rtc_open(struct inode *inode, struct file *file)

{

	lock_kernel();

	if(rtc_status) {

		unlock_kernel();

	if (!atomic_dec_and_test(&rtc_status)) {

		atomic_inc(&rtc_status);

		return -EBUSY;

	}



	rtc_status = 1;

	unlock_kernel();

	return 0;

}



static int rtc_release(struct inode *inode, struct file *file)

{

	lock_kernel();

	rtc_status = 0;

	unlock_kernel();

	atomic_inc(&rtc_status);

	return 0;

}
@@ -163,7 +152,7 @@ static int rtc_release(struct inode *inode, struct file *file) 
 */



static const struct file_operations rtc_fops = {

	.ioctl =	rtc_ioctl,

	.unlocked_ioctl	= rtc_ioctl,

	.open		= rtc_open,

	.release	= rtc_release,

};

arch/m68k/mvme16x/rtc.c

+5 −14
Original line number Diff line number Diff line
@@ -9,7 +9,6 @@ 
#include <linux/types.h>

#include <linux/errno.h>

#include <linux/miscdevice.h>

#include <linux/smp_lock.h>

#include <linux/ioport.h>

#include <linux/capability.h>

#include <linux/fcntl.h>
@@ -36,8 +35,7 @@ static const unsigned char days_in_mo[] = 


static atomic_t rtc_ready = ATOMIC_INIT(1);



static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,

		     unsigned long arg)

static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)

{

	volatile MK48T08ptr_t rtc = (MK48T08ptr_t)MVME_RTC_BASE;

	unsigned long flags;
@@ -121,21 +119,14 @@ static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd, 


/*

 * We enforce only one user at a time here with the open/close.

 *	Also clear the previous interrupt data on an open, and clean

 *	up things on a close.

 */



static int rtc_open(struct inode *inode, struct file *file)

{

	lock_kernel();

	if( !atomic_dec_and_test(&rtc_ready) )

	{

		atomic_inc( &rtc_ready );

		unlock_kernel();

		return -EBUSY;

	}

	unlock_kernel();



	return 0;

}
@@ -150,7 +141,7 @@ static int rtc_release(struct inode *inode, struct file *file) 
 */



static const struct file_operations rtc_fops = {

	.ioctl =	rtc_ioctl,

	.unlocked_ioctl	= rtc_ioctl,

	.open		= rtc_open,

	.release	= rtc_release,

};

CRA Git | Maintained and supported by SUSTech CRA and CCSE