ide: revert "ide: fix drive side 80c cable check, take 2" for now

"ide: fix drive side 80c cable check, take 2" patch from Tejun Heo (commit
fab59375b9543f84d1714f7dd00f5d11e531bd3e) fixed 80c bit test (bit13 of word93)
but we also need to fix master/slave IDENTIFY order (slave device should be
probed first in order to make it release PDIAG- signal) and we should also
check for pre-ATA3 slave devices (which may not release PDIAG- signal).

[ Unfortunately the fact that IDE driver doesn't reset devices itself helps
  only a bit as it seems that some BIOS-es reset ATA devices after programming
  the chipset, some BIOS-es can be set to not probe/configure selected devices,
  there may be no BIOS in case of add-on cards etc. ]

Since we are quite late in the release cycle and the required changes will
affect a lot of systems just revert the fix for now.

[ Please also see libata commit f31f0cc2f0b7527072d94d02da332d9bb8d7d94c. ]

Thanks goes out to Fernando Mitio Yamada for reporting the problem
and patiently testing patches.

Acked-by: Tejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

diff --git a/drivers/ide/ide-iops.c b/drivers/ide/ide-iops.c
index bd513f5a23236166541946391aab8239985201c9..5523c52fee7a2ca6debd1a4d81374e6e14d6798d 100644 (file)
--- a/drivers/ide/ide-iops.c
+++ b/drivers/ide/ide-iops.c
@@ -583,8 +583,12 @@ u8 eighty_ninty_three (ide_drive_t *drive)
        if(!(drive->id->hw_config & 0x4000))
                return 0;
 #endif /* CONFIG_IDEDMA_IVB */
-       if (!(drive->id->hw_config & 0x2000))
-               return 0;
+       /*
+        * FIXME:
+        * - change master/slave IDENTIFY order
+        * - force bit13 (80c cable present) check
+        *   (unless the slave device is pre-ATA3)
+        */
        return 1;
 }