libata: Fix (hopefully) all the remaining problems with devices failing setup/identify

diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.20-rc6-mm3/drivers/ata/libata-core.c linux-2.6.20-rc6-mm3/drivers/ata/libata-core.c
@@ -2404,6 +2418,10 @@
 		dev->flags |= ATA_DFLAG_PIO;
 
 	err_mask = ata_dev_set_xfermode(dev);
+	/* Old CFA may refuse this command, which is just fine */
+	if (dev->xfer_shift == ATA_SHIFT_PIO && ata_id_is_cfa(dev->id))
+        	err_mask &= ~AC_ERR_DEV;
+
 	if (err_mask) {
 		ata_dev_printk(dev, KERN_ERR, "failed to set xfermode "
 			       "(err_mask=0x%x)\n", err_mask);

@@ -5088,6 +5119,7 @@
 {
 	struct ata_eh_info *ehi = &ap->eh_info;
 	u8 status, host_stat = 0;
+	int i;
 
 	VPRINTK("ata%u: protocol %d task_state %d\n",
 		ap->id, qc->tf.protocol, ap->hsm_task_state);

@@ -5142,6 +5174,20 @@
 	status = ata_chk_status(ap);
 	if (unlikely(status & ATA_BUSY))
 		goto idle_irq;
+		
+	if (unlikely(qc->tf.command == ATA_CMD_SET_FEATURES && 
+			qc->tf.feature == SETFEATURES_XFER)) {
+		/* Let the timings change settle and the drive catch up as
+		   some hardware needs up to 10uS to get its brain back in
+		   gear. Taken from the workarounds in drivers/ide done by
+		   Matthew Faupel/Niccolo Rigacci */
+		for (i = 0; i < 10; i++) {
+			if ((status & (ATA_BUSY | ATA_DRQ | ATA_ERR)) == 0)
+				break;
+			udelay(1);
+			status = ata_chk_status(ap);
+		}
+	}
 
 	/* ack bmdma irq events */
 	ap->ops->irq_clear(ap);

@@ -1052,6 +1053,8 @@
 /**
  *	ata_busy_wait - Wait for a port status register
  *	@ap: Port to wait for.
+ *	@bits: bits that must be clear
+ *	@max: number of 10uS waits to perform
  *
  *	Waits up to max*10 microseconds for the selected bits in the port's
  *	status register to be cleared.