* [PATCH 1/1] Char: istallion, init+locking fixes
@ 2007-06-18 20:57 Ingo Korb
2007-06-19 7:42 ` Jiri Slaby
0 siblings, 1 reply; 4+ messages in thread
From: Ingo Korb @ 2007-06-18 20:57 UTC (permalink / raw)
To: Andrew Morton; +Cc: linux-kernel
Move brdp->iosize assignment in stli_initecp up a few lines to stop the
driver from requesting an I/O region of length 0.
Remove spin_lock_irqsave/spin_unlock_irqrestore from __stli_sendcmd as
all users of that function take the lock already.
Signed-off-by: Ingo Korb <ml@akana.de>
---
One thing I dislike about this driver: It polls its cards every jiffy to
look for new data. The cards are able to use interrupts (some of the
drivers for other OSes use them), but as far as I know there is no open
documentation. Unfortunately the DOS driver (probably easiest to
analyze) also uses polling. =(
diff --git a/drivers/char/istallion.c b/drivers/char/istallion.c
index 7b279d1..0bc1c37 100644
--- a/drivers/char/istallion.c
+++ b/drivers/char/istallion.c
@@ -2168,8 +2168,6 @@ static void __stli_sendcmd(struct stlibrd *brdp, struct stliport *portp, unsigne
unsigned char __iomem *bits;
unsigned long flags;
- spin_lock_irqsave(&brd_lock, flags);
-
if (test_bit(ST_CMDING, &portp->state)) {
printk(KERN_ERR "STALLION: command already busy, cmd=%x!\n",
(int) cmd);
@@ -2194,7 +2192,6 @@ static void __stli_sendcmd(struct stlibrd *brdp, struct stliport *portp, unsigne
writeb(readb(bits) | portp->portbit, bits);
set_bit(ST_CMDING, &portp->state);
EBRDDISABLE(brdp);
- spin_unlock_irqrestore(&brd_lock, flags);
}
static void stli_sendcmd(struct stlibrd *brdp, struct stliport *portp, unsigned long cmd, void *arg, int size, int copyback)
@@ -3218,13 +3215,13 @@ static int stli_initecp(struct stlibrd *brdp)
goto err;
}
+ brdp->iosize = ECP_IOSIZE;
+
if (!request_region(brdp->iobase, brdp->iosize, "istallion")) {
retval = -EIO;
goto err;
}
- brdp->iosize = ECP_IOSIZE;
-
/*
* Based on the specific board type setup the common vars to access
* and enable shared memory. Set all board specific information now
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH 1/1] Char: istallion, init+locking fixes
2007-06-18 20:57 [PATCH 1/1] Char: istallion, init+locking fixes Ingo Korb
@ 2007-06-19 7:42 ` Jiri Slaby
2007-06-19 14:32 ` Ingo Korb
2007-06-19 14:39 ` [PATCH 1/1] Char: istallion, init+locking fixes (try 2) Ingo Korb
0 siblings, 2 replies; 4+ messages in thread
From: Jiri Slaby @ 2007-06-19 7:42 UTC (permalink / raw)
To: Ingo Korb; +Cc: Andrew Morton, linux-kernel, Alan Cox
Ingo Korb napsal(a):
> Move brdp->iosize assignment in stli_initecp up a few lines to stop the
> driver from requesting an I/O region of length 0.
>
> Remove spin_lock_irqsave/spin_unlock_irqrestore from __stli_sendcmd as
> all users of that function take the lock already.
>
> Signed-off-by: Ingo Korb <ml@akana.de>
> ---
> One thing I dislike about this driver: It polls its cards every jiffy to
> look for new data. The cards are able to use interrupts (some of the
> drivers for other OSes use them), but as far as I know there is no open
> documentation. Unfortunately the DOS driver (probably easiest to
> analyze) also uses polling. =(
>
>
> diff --git a/drivers/char/istallion.c b/drivers/char/istallion.c
> index 7b279d1..0bc1c37 100644
> --- a/drivers/char/istallion.c
> +++ b/drivers/char/istallion.c
> @@ -2168,8 +2168,6 @@ static void __stli_sendcmd(struct stlibrd *brdp, struct stliport *portp, unsigne
> unsigned char __iomem *bits;
> unsigned long flags;
Remove the flags and you will see the bug, you introduced ;).
> - spin_lock_irqsave(&brd_lock, flags);
> -
> if (test_bit(ST_CMDING, &portp->state)) {
> printk(KERN_ERR "STALLION: command already busy, cmd=%x!\n",
> (int) cmd);
> @@ -2194,7 +2192,6 @@ static void __stli_sendcmd(struct stlibrd *brdp, struct stliport *portp, unsigne
> writeb(readb(bits) | portp->portbit, bits);
> set_bit(ST_CMDING, &portp->state);
> EBRDDISABLE(brdp);
> - spin_unlock_irqrestore(&brd_lock, flags);
> }
regards,
--
http://www.fi.muni.cz/~xslaby/ Jiri Slaby
faculty of informatics, masaryk university, brno, cz
e-mail: jirislaby gmail com, gpg pubkey fingerprint:
B674 9967 0407 CE62 ACC8 22A0 32CC 55C3 39D4 7A7E
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH 1/1] Char: istallion, init+locking fixes
2007-06-19 7:42 ` Jiri Slaby
@ 2007-06-19 14:32 ` Ingo Korb
2007-06-19 14:39 ` [PATCH 1/1] Char: istallion, init+locking fixes (try 2) Ingo Korb
1 sibling, 0 replies; 4+ messages in thread
From: Ingo Korb @ 2007-06-19 14:32 UTC (permalink / raw)
To: Jiri Slaby; +Cc: Andrew Morton, linux-kernel, Alan Cox
Jiri Slaby <jirislaby@gmail.com> writes:
>> unsigned char __iomem *bits;
>> unsigned long flags;
>
> Remove the flags and you will see the bug, you introduced ;).
Oops. I guess I shouldn't try to work on kernel stuff while tired. Fixed
patch follows.
-ik
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH 1/1] Char: istallion, init+locking fixes (try 2)
2007-06-19 7:42 ` Jiri Slaby
2007-06-19 14:32 ` Ingo Korb
@ 2007-06-19 14:39 ` Ingo Korb
1 sibling, 0 replies; 4+ messages in thread
From: Ingo Korb @ 2007-06-19 14:39 UTC (permalink / raw)
To: Jiri Slaby; +Cc: Andrew Morton, linux-kernel, Alan Cox
Move brdp->iosize assignment in stli_initecp up a few lines to stop the
driver from requesting an I/O region of length 0.
Remove spin_lock_irqsave/spin_unlock_irqrestore from __stli_sendcmd as
all users of that function take the lock already.
Signed-off-by: Ingo Korb <ml@akana.de>
---
diff --git a/drivers/char/istallion.c b/drivers/char/istallion.c
index 7b279d1..becba24 100644
--- a/drivers/char/istallion.c
+++ b/drivers/char/istallion.c
@@ -2166,14 +2166,10 @@ static void __stli_sendcmd(struct stlibrd *brdp, struct stliport *portp, unsigne
cdkhdr_t __iomem *hdrp;
cdkctrl_t __iomem *cp;
unsigned char __iomem *bits;
- unsigned long flags;
-
- spin_lock_irqsave(&brd_lock, flags);
if (test_bit(ST_CMDING, &portp->state)) {
printk(KERN_ERR "STALLION: command already busy, cmd=%x!\n",
(int) cmd);
- spin_unlock_irqrestore(&brd_lock, flags);
return;
}
@@ -2194,7 +2190,6 @@ static void __stli_sendcmd(struct stlibrd *brdp, struct stliport *portp, unsigne
writeb(readb(bits) | portp->portbit, bits);
set_bit(ST_CMDING, &portp->state);
EBRDDISABLE(brdp);
- spin_unlock_irqrestore(&brd_lock, flags);
}
static void stli_sendcmd(struct stlibrd *brdp, struct stliport *portp, unsigned long cmd, void *arg, int size, int copyback)
@@ -3218,13 +3213,13 @@ static int stli_initecp(struct stlibrd *brdp)
goto err;
}
+ brdp->iosize = ECP_IOSIZE;
+
if (!request_region(brdp->iobase, brdp->iosize, "istallion")) {
retval = -EIO;
goto err;
}
- brdp->iosize = ECP_IOSIZE;
-
/*
* Based on the specific board type setup the common vars to access
* and enable shared memory. Set all board specific information now
^ permalink raw reply related [flat|nested] 4+ messages in thread
end of thread, other threads:[~2007-06-19 14:40 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2007-06-18 20:57 [PATCH 1/1] Char: istallion, init+locking fixes Ingo Korb
2007-06-19 7:42 ` Jiri Slaby
2007-06-19 14:32 ` Ingo Korb
2007-06-19 14:39 ` [PATCH 1/1] Char: istallion, init+locking fixes (try 2) Ingo Korb
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