[libata] remove ata_chk_err(), ->check_err() hook.

We now depend on ->tf_read() to provide us with the contents
of the Error shadow register.
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index b1b1c6f..d2f71a2 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -371,7 +371,7 @@
 	struct ata_ioports *ioaddr = &ap->ioaddr;
 
 	tf->command = ata_check_status(ap);
-	tf->feature = ata_chk_err(ap);
+	tf->feature = inb(ioaddr->error_addr);
 	tf->nsect = inb(ioaddr->nsect_addr);
 	tf->lbal = inb(ioaddr->lbal_addr);
 	tf->lbam = inb(ioaddr->lbam_addr);
@@ -405,7 +405,7 @@
 	struct ata_ioports *ioaddr = &ap->ioaddr;
 
 	tf->command = ata_check_status(ap);
-	tf->feature = ata_chk_err(ap);
+	tf->feature = readb((void __iomem *)ioaddr->error_addr);
 	tf->nsect = readb((void __iomem *)ioaddr->nsect_addr);
 	tf->lbal = readb((void __iomem *)ioaddr->lbal_addr);
 	tf->lbam = readb((void __iomem *)ioaddr->lbam_addr);
@@ -526,30 +526,6 @@
 
 
 /**
- *	ata_chk_err - Read device error reg
- *	@ap: port where the device is
- *
- *	Reads ATA taskfile error register for
- *	currently-selected device and return its value.
- *
- *	Note: may NOT be used as the check_err() entry in
- *	ata_port_operations.
- *
- *	LOCKING:
- *	Inherited from caller.
- */
-u8 ata_chk_err(struct ata_port *ap)
-{
-	if (ap->ops->check_err)
-		return ap->ops->check_err(ap);
-
-	if (ap->flags & ATA_FLAG_MMIO) {
-		return readb((void __iomem *) ap->ioaddr.error_addr);
-	}
-	return inb(ap->ioaddr.error_addr);
-}
-
-/**
  *	ata_tf_to_fis - Convert ATA taskfile to SATA FIS structure
  *	@tf: Taskfile to convert
  *	@fis: Buffer into which data will output
@@ -901,8 +877,8 @@
 
 	memset(&tf, 0, sizeof(tf));
 
-	err = ata_chk_err(ap);
 	ap->ops->tf_read(ap, &tf);
+	err = tf.feature;
 
 	dev->class = ATA_DEV_NONE;
 
@@ -1139,7 +1115,6 @@
 	unsigned int major_version;
 	u16 tmp;
 	unsigned long xfer_modes;
-	u8 status;
 	unsigned int using_edd;
 	DECLARE_COMPLETION(wait);
 	struct ata_queued_cmd *qc;
@@ -1193,8 +1168,11 @@
 	else
 		wait_for_completion(&wait);
 
-	status = ata_chk_status(ap);
-	if (status & ATA_ERR) {
+	spin_lock_irqsave(&ap->host_set->lock, flags);
+	ap->ops->tf_read(ap, &qc->tf);
+	spin_unlock_irqrestore(&ap->host_set->lock, flags);
+
+	if (qc->tf.command & ATA_ERR) {
 		/*
 		 * arg!  EDD works for all test cases, but seems to return
 		 * the ATA signature for some ATAPI devices.  Until the
@@ -1207,7 +1185,7 @@
 		 * to have this problem.
 		 */
 		if ((using_edd) && (qc->tf.command == ATA_CMD_ID_ATA)) {
-			u8 err = ata_chk_err(ap);
+			u8 err = qc->tf.feature;
 			if (err & ATA_ABORTED) {
 				dev->class = ATA_DEV_ATAPI;
 				qc->cursg = 0;
@@ -4873,7 +4851,6 @@
 EXPORT_SYMBOL_GPL(ata_tf_from_fis);
 EXPORT_SYMBOL_GPL(ata_check_status);
 EXPORT_SYMBOL_GPL(ata_altstatus);
-EXPORT_SYMBOL_GPL(ata_chk_err);
 EXPORT_SYMBOL_GPL(ata_exec_command);
 EXPORT_SYMBOL_GPL(ata_port_start);
 EXPORT_SYMBOL_GPL(ata_port_stop);