[PATCH] pata_jmicron: fix disabled port handling in jmicron_pre_reset()

[PATCH] pata_jmicron: fix disabled port handling in jmicron_pre_reset()

[Tejun Heo]

There are two bugs in disabled port handling.

* test in PORT_PATA0 is reversed
* ->prereset should return -ENOENT for disabled ports not 0

The first bug makes the PATA channel considered disabled but the
second bug saves the day by returning 0.  The net result is that cable
is always left at ATA_CBL_UNKNOWN.  This results in false 80c
configuration and thus transfer errors.

This patch fixes both bugs.

Signed-off-by: Tejun Heo <htejun@gmail.com>
---
applied to #tj-upstream-fixes.

 drivers/ata/pata_jmicron.c |    9 ++++-----
 1 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/ata/pata_jmicron.c b/drivers/ata/pata_jmicron.c
index 225a722..5b8174d 100644
--- a/drivers/ata/pata_jmicron.c
+++ b/drivers/ata/pata_jmicron.c
@@ -80,11 +80,10 @@ static int jmicron_pre_reset(struct ata_link *link, unsigned long deadline)
 	 *	actually do our cable checking etc. Thankfully we don't need
 	 *	to do the plumbing for other cases.
 	 */
-	switch (port_map[port])
-	{
+	switch (port_map[port]) {
 	case PORT_PATA0:
-		if (control & (1 << 5))
-			return 0;
+		if ((control & (1 << 5)) == 0)
+			return -ENOENT;
 		if (control & (1 << 3))	/* 40/80 pin primary */
 			ap->cbl = ATA_CBL_PATA40;
 		else
@@ -93,7 +92,7 @@ static int jmicron_pre_reset(struct ata_link *link, unsigned long deadline)
 	case PORT_PATA1:
 		/* Bit 21 is set if the port is enabled */
 		if ((control5 & (1 << 21)) == 0)
-			return 0;
+			return -ENOENT;
 		if (control5 & (1 << 19))	/* 40/80 pin secondary */
 			ap->cbl = ATA_CBL_PATA40;
 		else
-- 
1.5.2.4

Re: [PATCH] pata_jmicron: fix disabled port handling in jmicron_pre_reset()

[Tejun Heo]

Tejun Heo wrote:
> There are two bugs in disabled port handling.
> 
> * test in PORT_PATA0 is reversed
> * ->prereset should return -ENOENT for disabled ports not 0
> 
> The first bug makes the PATA channel considered disabled but the
> second bug saves the day by returning 0.  The net result is that cable
> is always left at ATA_CBL_UNKNOWN.  This results in false 80c
> configuration and thus transfer errors.
> 
> This patch fixes both bugs.
> 
> Signed-off-by: Tejun Heo <htejun@gmail.com>

Jeff, this wasn't pushed to Linus.  Can you please put this into
#upstream-fixes?

Thanks.

-- 
tejun

Re: [PATCH] pata_jmicron: fix disabled port handling in jmicron_pre_reset()

[Jeff Garzik]

Tejun Heo wrote:
> There are two bugs in disabled port handling.
> 
> * test in PORT_PATA0 is reversed
> * ->prereset should return -ENOENT for disabled ports not 0
> 
> The first bug makes the PATA channel considered disabled but the
> second bug saves the day by returning 0.  The net result is that cable
> is always left at ATA_CBL_UNKNOWN.  This results in false 80c
> configuration and thus transfer errors.
> 
> This patch fixes both bugs.
> 
> Signed-off-by: Tejun Heo <htejun@gmail.com>
> ---
> applied to #tj-upstream-fixes.
> 
>  drivers/ata/pata_jmicron.c |    9 ++++-----
>  1 files changed, 4 insertions(+), 5 deletions(-)

applied