Djam/u-boot
1
0
Fork 0
mirror of https://github.com/u-boot/u-boot.git synced 2025-04-23 13:56:20 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

dm: core: Add a helper to retrieve devices through graph endpoints

Browse source 
There are already several helpers to find a udevice based on its
position in a device tree, like getting a child or a node pointed by a
phandle, but there was no support for graph endpoints, which are very
common in display pipelines.

Add a new helper, named uclass_get_device_by_endpoint() which enters the
child graph reprensentation, looks for a specific port, then follows the
remote endpoint, and finally retrieves the first parent of the given
uclass_id.

This is a very handy and straightforward way to get a bridge or a panel
handle.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
This commit is contained in:
Miquel Raynal 2025-04-03 09:39:03 +02:00 • committed by Fabio Estevam
parent 9fe367bb60
commit 04fcddac28
2 changed files with 43 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

19
drivers/core/uclass.c
View file

@ -16,6 +16,7 @@
#include <dm/device.h>
#include <dm/device-internal.h>
#include <dm/lists.h>
#include <dm/ofnode_graph.h>
#include <dm/uclass.h>
#include <dm/uclass-internal.h>
#include <dm/util.h>
@ -582,6 +583,24 @@ int uclass_get_device_by_phandle(enum uclass_id id, struct udevice *parent,
ret = uclass_find_device_by_phandle(id, parent, name, &dev);
return uclass_get_device_tail(dev, ret, devp);
}
int uclass_get_device_by_endpoint(enum uclass_id class_id, struct udevice *dev,
int port_idx, int ep_idx, struct udevice **devp)
{
ofnode node_source = dev_ofnode(dev);
ofnode node_dest = ofnode_graph_get_remote_node(node_source, port_idx, ep_idx);
struct udevice *target = NULL;
int ret;
if (!ofnode_valid(node_dest))
return -EINVAL;
ret = uclass_find_device_by_ofnode(class_id, node_dest, &target);
if (ret)
return -ENODEV;
return uclass_get_device_tail(target, 0, devp);
}
#endif
/*

24
include/dm/uclass.h
View file

@ -333,6 +333,30 @@ int uclass_get_device_by_phandle(enum uclass_id id, struct udevice *parent,
int uclass_get_device_by_driver(enum uclass_id id, const struct driver *drv,
struct udevice **devp);
/**
* uclass_get_device_by_endpoint() - Get a uclass device for a remote endpoint
*
* This searches through the parents of the specified remote endpoint
* for the first device matching the uclass. Said otherwise, this helper
* goes through the graph (endpoint) representation and searches for
* matching devices. Endpoints can be subnodes of the "port" node or
* subnodes of ports identified with a reg property, themselves in a
* "ports" container.
*
* The device is probed to activate it ready for use.
*
* @class_id: uclass ID to look up
* @dev: Device to start from
* @port_idx: Index of the port to follow, -1 if there is a single 'port'
* node without reg.
* @ep_idx: Index of the endpoint to follow, -1 if there is a single 'endpoint'
* node without reg.
* @target: Returns pointer to the first device matching the expected uclass.
* Return: 0 if OK, -ve on error
*/
int uclass_get_device_by_endpoint(enum uclass_id class_id, struct udevice *dev,
int port_idx, int ep_idx, struct udevice **target);
/**
* uclass_first_device() - Get the first device in a uclass
*