Restore support for AEC6280M cards in aec62xx.c

Hi

This patch was initially sent to linux-ide about a month ago, and was supposed to hit -mm, see:

http://marc.theaimsgroup.com/?l=linux-ide&m=113161988518500&w=2

As I didn't see this happening, I'm resending the patch, diff'd against 2.6.15-rc5. It fixes a serious bug that has been in the kernel for ages, preventing users of Macintosh-flavoured AEC cards to use them with Linux. The code has been brought up with the help of Benh.

HTH

T-Bone

ide-pci-aec62xx-maccards.diff:
This patch adds missing initialization sequence, necessary to get the "Macintosh" version of AEC6280 cards to work in Linux. Without this patch, the driver hangs for several minutes trying to initialize the card and the kernel is left in an unstable state. This patch has been tested fine on ppc and i386.

 drivers/ide/pci/aec62xx.c |   15 +++++++++++++++
 1 file changed, 15 insertions(+)

@@ -262,6 +262,21 @@
 	else
 		pci_set_drvdata(dev, (void *) aec6xxx_34_base);
 
+	/* These are necessary to get AEC6280 Macintosh cards to work */
+	if ((dev->device == PCI_DEVICE_ID_ARTOP_ATP865) ||
+	    (dev->device == PCI_DEVICE_ID_ARTOP_ATP865R)) {
+		u8 reg49h = 0, reg4ah = 0;
+		/* Clear reset and test bits.  */
+		pci_read_config_byte(dev, 0x49, &reg49h);
+		pci_write_config_byte(dev, 0x49, reg49h & ~0x30);
+		/* Enable chip interrupt output.  */
+		pci_read_config_byte(dev, 0x4a, &reg4ah);
+		pci_write_config_byte(dev, 0x4a, reg4ah & ~0x01);
+		/* Enable burst mode. */
+		pci_read_config_byte(dev, 0x4a, &reg4ah);
+		pci_write_config_byte(dev, 0x4a, reg4ah | 0x80);
+	}
+
 	return dev->irq;
 }