Hi Alan,

just a quick note to tell you that with ATA_ENABLE_PATA my
system works fine and does even survive suspend-to-ram.
This is a Samsung P35 laptop with one builtin 80 GB harddisk
and one builtin DVD-RAM drive.
libata patches are the ones included in 2.6.17-rc1-mm2 with
an additional one-liner:

--- drivers/scsi/ata_piix.c~    2006-04-11 14:11:11.000000000 +0200
+++ drivers/scsi/ata_piix.c     2006-04-11 01:02:55.000000000 +0200
@@ -157,6 +157,7 @@
 static const struct pci_device_id piix_pci_tbl[] = {
 #ifdef ATA_ENABLE_PATA
        { 0x8086, 0x7111, PCI_ANY_ID, PCI_ANY_ID, 0, 0, piix4_pata },
+       { 0x8086, 0x24ca, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich5_pata },
        { 0x8086, 0x24db, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich5_pata },
        { 0x8086, 0x25a2, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich5_pata },
 #endif


lspci -nvxxx is attached.
Excerpt from boot log under libata follows:

ata1: PATA max UDMA/100 cmd 0x1F0 ctl 0x3F6 bmdma 0x1860 irq 14
ata1: dev 0 cfg 49:2f00 82:346b 83:7f01 84:6003 85:3c69 86:3f01 87:6003 88:203f
ata1: dev 0 ATA-7, max UDMA/100, 156368016 sectors: LBA48
ata1: dev 0 configured for UDMA/100
scsi0 : ata_piix
  Vendor: ATA       Model: SAMSUNG MP0804H   Rev: UE10
  Type:   Direct-Access                      ANSI SCSI revision: 05
SCSI device sda: 156368016 512-byte hdwr sectors (80060 MB)
sda: Write Protect is off
sda: Mode Sense: 00 3a 00 00
SCSI device sda: drive cache: write back
SCSI device sda: 156368016 512-byte hdwr sectors (80060 MB)
sda: Write Protect is off
sda: Mode Sense: 00 3a 00 00
SCSI device sda: drive cache: write back
 sda: sda1 sda2 < sda5 sda6 sda7 sda8 sda9 >
sd 0:0:0:0: Attached scsi disk sda
ata2: PATA max UDMA/100 cmd 0x170 ctl 0x376 bmdma 0x1868 irq 15
ata2: dev 0 cfg 49:2f00 82:0000 83:0000 84:0000 85:0000 86:0000 87:0000 88:0407
ata2: dev 0 ATAPI, max UDMA/33
ata2: dev 0 configured for UDMA/33
scsi1 : ata_piix
  Vendor: TEAC      Model: DV-W24ES          Rev: S.0A
  Type:   CD-ROM                             ANSI SCSI revision: 05

If you need any additional information, holler.

Regards,
Carl-Daniel
-- 
http://www.hailfinger.org/