pata_jmicron: fix disabled port handling in jmicron_pre_reset()

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>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 4 insertions, 5 deletions

diff --git a/drivers/ata/pata_jmicron.c b/drivers/ata/pata_jmicron.c
index 225a7223a726..5b8174d94067 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