[libata] Disable ACPI by default; fix namespace problems

Not yet ready to turn on ATA ACPI by default, for either PATA or SATA.

Also, rename the global-scope module parameter variable 'noacpi' to
something more libata-specific, reducing the potential for namespace
collision.
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/ata/libata-acpi.c

@@ -305,7 +305,7 @@ static int do_drive_get_GTF(struct ata_port *ap, int ix,
 	*gtf_address = 0UL;
 	*obj_loc = 0UL;
 
-	if (noacpi)
+	if (libata_noacpi)
 		return 0;
 
 	if (ata_msg_probe(ap))
@@ -531,7 +531,7 @@ static int do_drive_set_taskfiles(struct ata_port *ap,
 		ata_dev_printk(atadev, KERN_DEBUG, "%s: ENTER: port#: %d\n",
 			       __FUNCTION__, ap->port_no);
 
-	if (noacpi || !(ap->cbl == ATA_CBL_SATA))
+	if (libata_noacpi || !(ap->cbl == ATA_CBL_SATA))
 		return 0;
 
 	if (!ata_dev_enabled(atadev) || (ap->flags & ATA_FLAG_DISABLED))
@@ -574,7 +574,7 @@ int ata_acpi_exec_tfs(struct ata_port *ap)
 	unsigned long	gtf_address;
 	unsigned long	obj_loc;
 
-	if (noacpi)
+	if (libata_noacpi)
 		return 0;
 	/*
 	 * TBD - implement PATA support.  For now,
@@ -636,7 +636,7 @@ int ata_acpi_push_id(struct ata_port *ap, unsigned int ix)
 	struct acpi_object_list         input;
 	union acpi_object               in_params[1];
 
-	if (noacpi)
+	if (libata_noacpi)
 		return 0;
 
 	if (ata_msg_probe(ap))

drivers/ata/libata-core.c

@@ -93,8 +93,8 @@ static int ata_probe_timeout = ATA_TMOUT_INTERNAL / HZ;
 module_param(ata_probe_timeout, int, 0444);
 MODULE_PARM_DESC(ata_probe_timeout, "Set ATA probing timeout (seconds)");
 
-int noacpi;
-module_param(noacpi, int, 0444);
+int libata_noacpi = 1;
+module_param_named(noacpi, libata_noacpi, int, 0444);
 MODULE_PARM_DESC(noacpi, "Disables the use of ACPI in suspend/resume when set");
 
 MODULE_AUTHOR("Jeff Garzik");

drivers/ata/libata.h

@@ -56,7 +56,7 @@ extern struct workqueue_struct *ata_aux_wq;
 extern int atapi_enabled;
 extern int atapi_dmadir;
 extern int libata_fua;
-extern int noacpi;
+extern int libata_noacpi;
 extern struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev);
 extern int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
 			   u64 block, u32 n_block, unsigned int tf_flags,