ACPI / bind: Redefine acpi_preset_companion()

Modify acpi_preset_companion() to take a struct acpi_device pointer
instead of an ACPI handle as its second argument and redefine it as
a static inline wrapper around ACPI_COMPANION_SET() passing the
return value of acpi_find_child_device() directly as the second
argument to it.  Update its users to pass struct acpi_device
pointers instead of ACPI handles to it.

This allows some unnecessary acpi_bus_get_device() calls to be
avoided.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Tested-by: Aaron Lu <aaron.lu@intel.com> # for ATA binding

drivers/acpi/glue.c

@@ -149,6 +149,7 @@ struct acpi_device *acpi_find_child_device(struct acpi_device *parent,
 	}
 	return ret;
 }
+EXPORT_SYMBOL_GPL(acpi_find_child_device);
 
 acpi_handle acpi_get_child(acpi_handle handle, u64 addr)
 {
@@ -298,15 +299,6 @@ int acpi_unbind_one(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(acpi_unbind_one);
 
-void acpi_preset_companion(struct device *dev, acpi_handle parent, u64 addr)
-{
-	struct acpi_device *adev;
-
-	if (!acpi_bus_get_device(acpi_get_child(parent, addr), &adev))
-		ACPI_COMPANION_SET(dev, adev);
-}
-EXPORT_SYMBOL_GPL(acpi_preset_companion);
-
 static int acpi_platform_notify(struct device *dev)
 {
 	struct acpi_bus_type *type = acpi_get_bus_type(dev);

drivers/ata/libata-acpi.c

@@ -178,12 +178,12 @@ static const struct acpi_dock_ops ata_acpi_ap_dock_ops = {
 /* bind acpi handle to pata port */
 void ata_acpi_bind_port(struct ata_port *ap)
 {
-	acpi_handle host_handle = ACPI_HANDLE(ap->host->dev);
+	struct acpi_device *host_companion = ACPI_COMPANION(ap->host->dev);
 
-	if (libata_noacpi || ap->flags & ATA_FLAG_ACPI_SATA || !host_handle)
+	if (libata_noacpi || ap->flags & ATA_FLAG_ACPI_SATA || !host_companion)
 		return;
 
-	acpi_preset_companion(&ap->tdev, host_handle, ap->port_no);
+	acpi_preset_companion(&ap->tdev, host_companion, ap->port_no);
 
 	if (ata_acpi_gtm(ap, &ap->__acpi_init_gtm) == 0)
 		ap->pflags |= ATA_PFLAG_INIT_GTM_VALID;
@@ -196,17 +196,17 @@ void ata_acpi_bind_port(struct ata_port *ap)
 void ata_acpi_bind_dev(struct ata_device *dev)
 {
 	struct ata_port *ap = dev->link->ap;
-	acpi_handle port_handle = ACPI_HANDLE(&ap->tdev);
-	acpi_handle host_handle = ACPI_HANDLE(ap->host->dev);
-	acpi_handle parent_handle;
+	struct acpi_device *port_companion = ACPI_COMPANION(&ap->tdev);
+	struct acpi_device *host_companion = ACPI_COMPANION(ap->host->dev);
+	struct acpi_device *parent;
 	u64 adr;
 
 	/*
-	 * For both sata/pata devices, host handle is required.
-	 * For pata device, port handle is also required.
+	 * For both sata/pata devices, host companion device is required.
+	 * For pata device, port companion device is also required.
 	 */
-	if (libata_noacpi || !host_handle ||
-			(!(ap->flags & ATA_FLAG_ACPI_SATA) && !port_handle))
+	if (libata_noacpi || !host_companion ||
+			(!(ap->flags & ATA_FLAG_ACPI_SATA) && !port_companion))
 		return;
 
 	if (ap->flags & ATA_FLAG_ACPI_SATA) {
@@ -214,13 +214,13 @@ void ata_acpi_bind_dev(struct ata_device *dev)
 			adr = SATA_ADR(ap->port_no, NO_PORT_MULT);
 		else
 			adr = SATA_ADR(ap->port_no, dev->link->pmp);
-		parent_handle = host_handle;
+		parent = host_companion;
 	} else {
 		adr = dev->devno;
-		parent_handle = port_handle;
+		parent = port_companion;
 	}
 
-	acpi_preset_companion(&dev->tdev, parent_handle, adr);
+	acpi_preset_companion(&dev->tdev, parent, adr);
 
 	register_hotplug_dock_device(ata_dev_acpi_handle(dev),
 				     &ata_acpi_dev_dock_ops, dev, NULL, NULL);

drivers/mmc/core/sdio_bus.c

@@ -308,7 +308,7 @@ static void sdio_acpi_set_handle(struct sdio_func *func)
 	struct mmc_host *host = func->card->host;
 	u64 addr = (host->slotno << 16) | func->num;
 
-	acpi_preset_companion(&func->dev, ACPI_HANDLE(host->parent), addr);
+	acpi_preset_companion(&func->dev, ACPI_COMPANION(host->parent), addr);
 }
 #else
 static inline void sdio_acpi_set_handle(struct sdio_func *func) {}

include/acpi/acpi_bus.h

@@ -435,7 +435,6 @@ struct acpi_pci_root {
 struct acpi_device *acpi_find_child_device(struct acpi_device *parent,
 					   u64 address, bool check_children);
 acpi_handle acpi_get_child(acpi_handle handle, u64 addr);
-void acpi_preset_companion(struct device *dev, acpi_handle parent, u64 addr);
 int acpi_is_root_bridge(acpi_handle);
 struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle);
 

include/linux/acpi.h

@@ -53,6 +53,12 @@ static inline acpi_handle acpi_device_handle(struct acpi_device *adev)
 #define ACPI_COMPANION_SET(dev, adev)	ACPI_COMPANION(dev) = (adev)
 #define ACPI_HANDLE(dev)		acpi_device_handle(ACPI_COMPANION(dev))
 
+static inline void acpi_preset_companion(struct device *dev,
+					 struct acpi_device *parent, u64 addr)
+{
+	ACPI_COMPANION_SET(dev, acpi_find_child_device(parent, addr, NULL));
+}
+
 static inline const char *acpi_dev_name(struct acpi_device *adev)
 {
 	return dev_name(&adev->dev);