hpt366: add debounce delay to cable_detect() method

Alan Cox reported that cable detection sometimes works unreliably
for HPT3xxN and that the issue is fixed by adding debounce delay
as used by the vendor drivers.

While at it, get rid of unneeded parens/space in the vicinity...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 5 deletions

diff --git a/drivers/ide/hpt366.c b/drivers/ide/hpt366.c
index 97d98fbf5849..c613ae170a84 100644
--- a/drivers/ide/hpt366.c
+++ b/drivers/ide/hpt366.c
@@ -1173,8 +1173,9 @@ static u8 hpt3xx_cable_detect(ide_hwif_t *hwif)
                 u16 mcr;
 
                 pci_read_config_word(dev, mcr_addr, &mcr);
-                pci_write_config_word(dev, mcr_addr, (mcr | 0x8000));
-                /* now read cable id register */
+                pci_write_config_word(dev, mcr_addr, mcr | 0x8000);
+                /* Debounce, then read cable ID register */
+                udelay(10);
                 pci_read_config_byte(dev, 0x5a, &scr1);
                 pci_write_config_word(dev, mcr_addr, mcr);
         } else if (chip_type >= HPT370) {
@@ -1185,10 +1186,11 @@ static u8 hpt3xx_cable_detect(ide_hwif_t *hwif)
                 u8 scr2 = 0;
 
                 pci_read_config_byte(dev, 0x5b, &scr2);
-                pci_write_config_byte(dev, 0x5b, (scr2 & ~1));
-                /* now read cable id register */
+                pci_write_config_byte(dev, 0x5b, scr2 & ~1);
+                /* Debounce, then read cable ID register */
+                udelay(10);
                 pci_read_config_byte(dev, 0x5a, &scr1);
-                pci_write_config_byte(dev, 0x5b,  scr2);
+                pci_write_config_byte(dev, 0x5b, scr2);
         } else
                 pci_read_config_byte(dev, 0x5a, &scr1);