ide: refactor tf_read() method

Simplify tf_read() method, making it deal only with 'struct ide_taskfile' and
the validity flags that the upper layer passes, and factoring out the code that
deals with the high order bytes into ide_tf_readback() to be called from the
only two functions interested, ide_complete_cmd() and ide_dump_sector().

This should stop the needless code duplication in this method and so make
it about twice smaller than it was; along with simplifying the setup for
the method call, this should save both time and space...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/include/linux/ide.h b/include/linux/ide.h
index 0ba1c6a..ff65fff 100644
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -625,7 +625,7 @@
 
 	void	(*dev_select)(ide_drive_t *);
 	void	(*tf_load)(ide_drive_t *, struct ide_taskfile *, u8);
-	void	(*tf_read)(ide_drive_t *, struct ide_cmd *);
+	void	(*tf_read)(ide_drive_t *, struct ide_taskfile *, u8);
 
 	void	(*input_data)(ide_drive_t *, struct ide_cmd *,
 			      void *, unsigned int);
@@ -1124,6 +1124,7 @@
 void ide_complete_cmd(ide_drive_t *, struct ide_cmd *, u8, u8);
 int ide_complete_rq(ide_drive_t *, int, unsigned int);
 
+void ide_tf_readback(ide_drive_t *drive, struct ide_cmd *cmd);
 void ide_tf_dump(const char *, struct ide_cmd *);
 
 void ide_exec_command(ide_hwif_t *, u8);
@@ -1133,7 +1134,7 @@
 
 void ide_dev_select(ide_drive_t *);
 void ide_tf_load(ide_drive_t *, struct ide_taskfile *, u8);
-void ide_tf_read(ide_drive_t *, struct ide_cmd *);
+void ide_tf_read(ide_drive_t *, struct ide_taskfile *, u8);
 
 void ide_input_data(ide_drive_t *, struct ide_cmd *, void *, unsigned int);
 void ide_output_data(ide_drive_t *, struct ide_cmd *, void *, unsigned int);