Forward port the replacement to the horribly broken locking in 2.5
radio_cadet driver.
diff -u --new-file --recursive --exclude-from /usr/src/exclude linux-2.5.66-bk3/drivers/media/radio/radio-cadet.c linux-2.5.66-ac1/drivers/media/radio/radio-cadet.c
--- linux-2.5.66-bk3/drivers/media/radio/radio-cadet.c 2003-03-27 17:13:02.000000000 +0000
+++ linux-2.5.66-ac1/drivers/media/radio/radio-cadet.c 2003-03-23 23:41:29.000000000 +0000
@@ -23,7 +23,9 @@
* 2002-01-17 Adam Belay <ambx1@neo.rr.com>
* Updated to latest pnp code
*
-*/
+ * 2003-01-31 Alan Cox <alan@redhat.com>
+ * Cleaned up locking, delay code, general odds and ends
+ */
#include <linux/module.h> /* Modules */
#include <linux/init.h> /* Initdata */
@@ -43,11 +45,11 @@
static int curtuner=0;
static int tunestat=0;
static int sigstrength=0;
-static wait_queue_head_t tunerq,rdsq,readq;
+static wait_queue_head_t readq;
struct timer_list tunertimer,rdstimer,readtimer;
static __u8 rdsin=0,rdsout=0,rdsstat=0;
static unsigned char rdsbuf[RDS_BUFFER];
-static int cadet_lock=0;
+static spinlock_t cadet_io_lock;
static int cadet_probe(void);
@@ -58,37 +60,19 @@
*/
static __u16 sigtable[2][4]={{5,10,30,150},{28,40,63,1000}};
-static void cadet_wake(unsigned long qnum)
-{
- switch(qnum) {
- case 0: /* cadet_setfreq */
- wake_up(&tunerq);
- break;
- case 1: /* cadet_getrds */
- wake_up(&rdsq);
- break;
- }
-}
-
-
-
static int cadet_getrds(void)
{
int rdsstat=0;
- cadet_lock++;
+ spin_lock(&cadet_io_lock);
outb(3,io); /* Select Decoder Control/Status */
outb(inb(io+1)&0x7f,io+1); /* Reset RDS detection */
- cadet_lock--;
- init_timer(&rdstimer);
- rdstimer.function=cadet_wake;
- rdstimer.data=(unsigned long)1;
- rdstimer.expires=jiffies+(HZ/10);
- init_waitqueue_head(&rdsq);
- add_timer(&rdstimer);
- sleep_on(&rdsq);
+ spin_unlock(&cadet_io_lock);
- cadet_lock++;
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule_timeout(HZ/10);
+
+ spin_lock(&cadet_io_lock);
outb(3,io); /* Select Decoder Control/Status */
if((inb(io+1)&0x80)!=0) {
rdsstat|=VIDEO_TUNER_RDS_ON;
@@ -96,32 +80,24 @@
if((inb(io+1)&0x10)!=0) {
rdsstat|=VIDEO_TUNER_MBS_ON;
}
- cadet_lock--;
+ spin_unlock(&cadet_io_lock);
return rdsstat;
}
-
-
-
static int cadet_getstereo(void)
{
- if(curtuner!=0) { /* Only FM has stereo capability! */
+ int ret = 0;
+ if(curtuner != 0) /* Only FM has stereo capability! */
return 0;
- }
- cadet_lock++;
+
+ spin_lock(&cadet_io_lock);
outb(7,io); /* Select tuner control */
- if((inb(io+1)&0x40)==0) {
- cadet_lock--;
- return 1; /* Stereo pilot detected */
- }
- else {
- cadet_lock--;
- return 0; /* Mono */
- }
+ if( (inb(io+1) & 0x40) == 0)
+ ret = 1;
+ spin_unlock(&cadet_io_lock);
+ return ret;
}
-
-
static unsigned cadet_gettune(void)
{
int curvol,i;
@@ -130,7 +106,9 @@
/*
* Prepare for read
*/
- cadet_lock++;
+
+ spin_lock(&cadet_io_lock);
+
outb(7,io); /* Select tuner control */
curvol=inb(io+1); /* Save current volume/mute setting */
outb(0x00,io+1); /* Ensure WRITE-ENABLE is LOW */
@@ -152,13 +130,11 @@
* Restore volume/mute setting
*/
outb(curvol,io+1);
- cadet_lock--;
+ spin_unlock(&cadet_io_lock);
return fifo;
}
-
-
static unsigned cadet_getfreq(void)
{
int i;
@@ -191,14 +167,13 @@
return freq;
}
-
-
static void cadet_settune(unsigned fifo)
{
int i;
unsigned test;
- cadet_lock++;
+ spin_lock(&cadet_io_lock);
+
outb(7,io); /* Select tuner control */
/*
* Write the shift register
@@ -217,11 +192,9 @@
test=0x1c|((fifo>>23)&0x02);
outb(test,io+1);
}
- cadet_lock--;
+ spin_unlock(&cadet_io_lock);
}
-
-
static void cadet_setfreq(unsigned freq)
{
unsigned fifo;
@@ -253,92 +226,90 @@
/*
* Save current volume/mute setting
*/
- cadet_lock++;
+
+ spin_lock(&cadet_io_lock);
outb(7,io); /* Select tuner control */
curvol=inb(io+1);
+ spin_unlock(&cadet_io_lock);
/*
* Tune the card
*/
for(j=3;j>-1;j--) {
cadet_settune(fifo|(j<<16));
+
+ spin_lock(&cadet_io_lock);
outb(7,io); /* Select tuner control */
outb(curvol,io+1);
- cadet_lock--;
- init_timer(&tunertimer);
- tunertimer.function=cadet_wake;
- tunertimer.data=(unsigned long)0;
- tunertimer.expires=jiffies+(HZ/10);
- init_waitqueue_head(&tunerq);
- add_timer(&tunertimer);
- sleep_on(&tunerq);
+ spin_unlock(&cadet_io_lock);
+
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule_timeout(HZ/10);
+
cadet_gettune();
- if((tunestat&0x40)==0) { /* Tuned */
+ if((tunestat & 0x40) == 0) { /* Tuned */
sigstrength=sigtable[curtuner][j];
return;
}
- cadet_lock++;
}
- cadet_lock--;
sigstrength=0;
}
static int cadet_getvol(void)
{
- cadet_lock++;
+ int ret = 0;
+
+ spin_lock(&cadet_io_lock);
+
outb(7,io); /* Select tuner control */
- if((inb(io+1)&0x20)!=0) {
- cadet_lock--;
- return 0xffff;
- }
- else {
- cadet_lock--;
- return 0;
- }
+ if((inb(io + 1) & 0x20) != 0)
+ ret = 0xffff;
+
+ spin_unlock(&cadet_io_lock);
+ return ret;
}
static void cadet_setvol(int vol)
{
- cadet_lock++;
+ spin_lock(&cadet_io_lock);
outb(7,io); /* Select tuner control */
- if(vol>0) {
+ if(vol>0)
outb(0x20,io+1);
- }
- else {
+ else
outb(0x00,io+1);
- }
- cadet_lock--;
+ spin_unlock(&cadet_io_lock);
}
-
-
void cadet_handler(unsigned long data)
{
/*
* Service the RDS fifo
*/
- if(cadet_lock==0) {
+
+ if(spin_trylock(&cadet_io_lock))
+ {
outb(0x3,io); /* Select RDS Decoder Control */
if((inb(io+1)&0x20)!=0) {
printk(KERN_CRIT "cadet: RDS fifo overflow\n");
}
outb(0x80,io); /* Select RDS fifo */
while((inb(io)&0x80)!=0) {
- rdsbuf[rdsin++]=inb(io+1);
- if(rdsin==rdsout) {
- printk(KERN_CRIT "cadet: RDS buffer overflow\n");
- }
+ rdsbuf[rdsin]=inb(io+1);
+ if(rdsin==rdsout)
+ printk(KERN_WARNING "cadet: RDS buffer overflow\n");
+ else
+ rdsin++;
}
+ spin_unlock(&cadet_io_lock);
}
/*
* Service pending read
*/
- if( rdsin!=rdsout) {
+ if( rdsin!=rdsout)
wake_up_interruptible(&readq);
- }
/*
* Clean up and exit
@@ -359,10 +330,10 @@
unsigned char readbuf[RDS_BUFFER];
if(rdsstat==0) {
- cadet_lock++;
+ spin_lock(&cadet_io_lock);
rdsstat=1;
outb(0x80,io); /* Select RDS fifo */
- cadet_lock--;
+ spin_unlock(&cadet_io_lock);
init_timer(&readtimer);
readtimer.function=cadet_handler;
readtimer.data=(unsigned long)0;
@@ -370,14 +341,13 @@
add_timer(&readtimer);
}
if(rdsin==rdsout) {
- if (file->f_flags & O_NONBLOCK) {
+ if (file->f_flags & O_NONBLOCK)
return -EWOULDBLOCK;
- }
interruptible_sleep_on(&readq);
}
- while((i<count)&&(rdsin!=rdsout)) {
+ while( i<count && rdsin!=rdsout)
readbuf[i++]=rdsbuf[rdsout++];
- }
+
if (copy_to_user(data,readbuf,i))
return -EFAULT;
return i;
@@ -515,10 +485,8 @@
static int cadet_release(struct inode *inode, struct file *file)
{
- if(rdsstat==1) {
- del_timer(&readtimer);
- rdsstat=0;
- }
+ del_timer_sync(&readtimer);
+ rdsstat=0;
users--;
return 0;
}
@@ -595,13 +563,15 @@
return -1;
}
- /*
- * io should only be set if the user has used something like
- * isapnp (the userspace program) to initialize this card for us
- */
+/*
+ * io should only be set if the user has used something like
+ * isapnp (the userspace program) to initialize this card for us
+ */
static int __init cadet_init(void)
{
+ spin_lock_init(&cadet_io_lock);
+
/*
* If a probe was requested then probe ISAPnP first (safest)
*/
-
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This archive was generated by hypermail 2b29 : Mon Mar 31 2003 - 22:00:28 EST