dm: core: Allow parents to have platform data for their children

For buses it is common for parents to need to know the address of the child
on the bus, the bus speed to use for that child, and other information. This
can be provided in platform data attached to each child.

Add driver model support for this, including auto-allocation which can be
requested using a new property to specify the size of the data.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/include/dm/device.h b/include/dm/device.h
index 13598a15b6..096d84b7b6 100644
--- a/include/dm/device.h
+++ b/include/dm/device.h
@@ -26,6 +26,9 @@ struct driver_info;
 /* DM should init this device prior to relocation */
 #define DM_FLAG_PRE_RELOC	(1 << 2)
 
+/* DM is responsible for allocating and freeing parent_platdata */
+#define DM_FLAG_ALLOC_PARENT_PDATA	(1 << 3)
+
 /**
  * struct udevice - An instance of a driver
  *
@@ -46,6 +49,7 @@ struct driver_info;
  * @driver: The driver used by this device
  * @name: Name of device, typically the FDT node name
  * @platdata: Configuration data for this device
+ * @parent_platdata: The parent bus's configuration data for this device
  * @of_offset: Device tree node offset for this device (- for none)
  * @of_id: Pointer to the udevice_id structure which created the device
  * @parent: Parent of this device, or NULL for the top level device
@@ -65,6 +69,7 @@ struct udevice {
 	struct driver *driver;
 	const char *name;
 	void *platdata;
+	void *parent_platdata;
 	int of_offset;
 	const struct udevice_id *of_id;
 	struct udevice *parent;
@@ -146,6 +151,9 @@ struct udevice_id {
  * device_probe_child() pass it in. So far the use case for allocating it
  * is SPI, but I found that unsatisfactory. Since it is here I will leave it
  * until things are clearer.
+ * @per_child_platdata_auto_alloc_size: A bus likes to store information about
+ * its children. If non-zero this is the size of this data, to be allocated
+ * in the child's parent_platdata pointer.
  * @ops: Driver-specific operations. This is typically a list of function
  * pointers defined by the driver, to implement driver functions required by
  * the uclass.
@@ -165,6 +173,7 @@ struct driver {
 	int priv_auto_alloc_size;
 	int platdata_auto_alloc_size;
 	int per_child_auto_alloc_size;
+	int per_child_platdata_auto_alloc_size;
 	const void *ops;	/* driver-specific operations */
 	uint32_t flags;
 };
@@ -184,6 +193,16 @@ struct driver {
 void *dev_get_platdata(struct udevice *dev);
 
 /**
+ * dev_get_parent_platdata() - Get the parent platform data for a device
+ *
+ * This checks that dev is not NULL, but no other checks for now
+ *
+ * @dev		Device to check
+ * @return parent's platform data, or NULL if none
+ */
+void *dev_get_parent_platdata(struct udevice *dev);
+
+/**
  * dev_get_parentdata() - Get the parent data for a device
  *
  * The parent data is data stored in the device but owned by the parent.