pata_sis: implement laptop list and add ASUS A6K/A6U

In ASUS A6K/A6U hdd is connected to SiS 96x via 40c cable, however it
is short cable and is UDMA66 capable.

tj: fixed if () conditionals
ah: fixed infinite loop

Signed-off-by: Jakub W. Jozwicki <jakub007@go2.pl>
Cc: Andreas Henriksson <andreas@fatal.se>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 30 insertions, 2 deletions

diff --git a/drivers/ata/pata_sis.c b/drivers/ata/pata_sis.c
index c434c4ef4e4b..d9486fcd59f2 100644
--- a/drivers/ata/pata_sis.c
+++ b/drivers/ata/pata_sis.c
@@ -43,6 +43,34 @@ struct sis_chipset {
            up code later */
 };
 
+struct sis_laptop {
+        u16 device;
+        u16 subvendor;
+        u16 subdevice;
+};
+
+static const struct sis_laptop sis_laptop[] = {
+        /* devid, subvendor, subdev */
+        { 0x5513, 0x1043, 0x1107 },     /* ASUS A6K */
+        /* end marker */
+        { 0, }
+};
+
+static int sis_short_ata40(struct pci_dev *dev)
+{
+        const struct sis_laptop *lap = &sis_laptop[0];
+
+        while (lap->device) {
+                if (lap->device == dev->device &&
+                    lap->subvendor == dev->subsystem_vendor &&
+                    lap->subdevice == dev->subsystem_device)
+                        return 1;
+                lap++;
+        }
+
+        return 0;
+}
+
 /**
  *      sis_port_base           -       return PCI configuration base for dev
  *      @adev: device
@@ -79,7 +107,7 @@ static int sis_133_pre_reset(struct ata_port *ap)
 
         /* The top bit of this register is the cable detect bit */
         pci_read_config_word(pdev, 0x50 + 2 * ap->port_no, &tmp);
-        if (tmp & 0x8000)
+        if ((tmp & 0x8000) && !sis_short_ata40(pdev))
                 ap->cbl = ATA_CBL_PATA40;
         else
                 ap->cbl = ATA_CBL_PATA80;
@@ -127,7 +155,7 @@ static int sis_66_pre_reset(struct ata_port *ap)
         /* Older chips keep cable detect in bits 4/5 of reg 0x48 */
         pci_read_config_byte(pdev, 0x48, &tmp);
         tmp >>= ap->port_no;
-        if (tmp & 0x10)
+        if ((tmp & 0x10) && !sis_short_ata40(pdev))
                 ap->cbl = ATA_CBL_PATA40;
         else
                 ap->cbl = ATA_CBL_PATA80;