dm: core: allow device_bind() to not return a device pointer

This is useful when we want to bind a device, but do not need the
pointer to the device.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>

drivers/core/device.c

@@ -32,7 +32,8 @@ int device_bind(struct udevice *parent, const struct driver *drv,
 	struct uclass *uc;
 	int size, ret = 0;
 
-	*devp = NULL;
+	if (devp)
+		*devp = NULL;
 	if (!name)
 		return -EINVAL;
 
@@ -133,7 +134,8 @@ int device_bind(struct udevice *parent, const struct driver *drv,
 
 	if (parent)
 		dm_dbg("Bound device %s to %s\n", dev->name, parent->name);
-	*devp = dev;
+	if (devp)
+		*devp = dev;
 
 	dev->flags |= DM_FLAG_BOUND;
 

include/dm/device-internal.h

@@ -31,7 +31,7 @@ struct udevice;
  * devices which use device tree.
  * @of_offset: Offset of device tree node for this device. This is -1 for
  * devices which don't use device tree.
- * @devp: Returns a pointer to the bound device
+ * @devp: if non-NULL, returns a pointer to the bound device
  * @return 0 if OK, -ve on error
  */
 int device_bind(struct udevice *parent, const struct driver *drv,
@@ -48,7 +48,7 @@ int device_bind(struct udevice *parent, const struct driver *drv,
  * @pre_reloc_only: If true, bind the driver only if its DM_INIT_F flag is set.
  * If false bind the driver always.
  * @info: Name and platdata for this device
- * @devp: Returns a pointer to the bound device
+ * @devp: if non-NULL, returns a pointer to the bound device
  * @return 0 if OK, -ve on error
  */
 int device_bind_by_name(struct udevice *parent, bool pre_reloc_only,

include/dm/lists.h

@@ -68,7 +68,7 @@ int lists_bind_fdt(struct udevice *parent, const void *blob, int offset,
  * @parent:	Parent device
  * @drv_name:	Name of driver to attach to this parent
  * @dev_name:	Name of the new device thus created
- * @devp:	Returns the newly bound device
+ * @devp:	If non-NULL, returns the newly bound device
  */
 int device_bind_driver(struct udevice *parent, const char *drv_name,
 		       const char *dev_name, struct udevice **devp);
@@ -83,7 +83,7 @@ int device_bind_driver(struct udevice *parent, const char *drv_name,
  * @drv_name:	Name of driver to attach to this parent
  * @dev_name:	Name of the new device thus created
  * @node:	Device tree node
- * @devp:	Returns the newly bound device
+ * @devp:	If non-NULL, returns the newly bound device
  */
 int device_bind_driver_to_node(struct udevice *parent, const char *drv_name,
 			       const char *dev_name, int node,