diff options
Diffstat (limited to 'drivers/base')
| -rw-r--r-- | drivers/base/swnode.c | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c index 869228a65cb3..1f2315858cc3 100644 --- a/drivers/base/swnode.c +++ b/drivers/base/swnode.c @@ -699,6 +699,62 @@ software_node_graph_parse_endpoint(const struct fwnode_handle *fwnode, return 0; } +static int software_node_add_links(struct fwnode_handle *fwnode) +{ + const struct software_node_ref_args *ref, *ref_array; + struct swnode *swnode = to_swnode(fwnode); + const struct property_entry *prop; + struct fwnode_handle *refnode; + unsigned int count; + + if (!swnode || !swnode->node->properties) + return 0; + + /* + * Unlike Device Tree, where phandles appear in many non-supplier + * contexts and a curated allowlist is required, a software node only + * carries a DEV_PROP_REF property when the author explicitly describes + * a reference to another node. Every such reference is therefore an + * intentional supplier dependency, so we create fwnode links for all + * of them. + */ + for (prop = swnode->node->properties; prop->name; prop++) { + if (prop->type != DEV_PROP_REF || prop->is_inline) + continue; + + /* + * TODO: Graph "remote-endpoint" references go both ways + * between endpoint child nodes and would create endpoint + * cycles. Let's leave it out for now until we have potential + * users. + */ + if (!strcmp(prop->name, "remote-endpoint")) + continue; + + ref_array = prop->pointer; + count = prop->length / sizeof(*ref_array); + + for (unsigned int i = 0; i < count; i++) { + ref = &ref_array[i]; + + if (ref->swnode) + refnode = software_node_fwnode(ref->swnode); + else if (ref->fwnode) + refnode = ref->fwnode; + else + continue; + + /* Supplier not registered yet, or self-reference. */ + if (!refnode || refnode == &swnode->fwnode) + continue; + + fwnode_link_add(&swnode->fwnode, refnode, 0); + } + } + + return 0; +} + static const struct fwnode_operations software_node_ops = { .get = software_node_get, .put = software_node_put, @@ -716,6 +772,7 @@ static const struct fwnode_operations software_node_ops = { .graph_get_remote_endpoint = software_node_graph_get_remote_endpoint, .graph_get_port_parent = software_node_graph_get_port_parent, .graph_parse_endpoint = software_node_graph_parse_endpoint, + .add_links = software_node_add_links, }; /* -------------------------------------------------------------------------- */ @@ -787,6 +844,8 @@ static void software_node_release(struct kobject *kobj) { struct swnode *swnode = kobj_to_swnode(kobj); + fwnode_links_purge(&swnode->fwnode); + if (swnode->parent) { ida_free(&swnode->parent->child_ids, swnode->id); list_del(&swnode->entry); @@ -1105,6 +1164,17 @@ void software_node_notify(struct device *dev) if (!swnode) return; + /* + * When the software node is the device's secondary firmware node, + * the core only records the owning device on the primary fwnode + * (see device_add()). fw_devlink resolves a supplier device through + * fwnode->dev, so without this a consumer referencing the software + * node could never find the supplier device and would defer forever. + * Make fwnode.dev point to its owner in that case. + */ + if (!device_match_fwnode(dev, &swnode->fwnode) && !swnode->fwnode.dev) + swnode->fwnode.dev = dev; + swnode_get(swnode); ret = sysfs_create_link(&dev->kobj, &swnode->kobj, "software_node"); if (ret) @@ -1127,6 +1197,15 @@ void software_node_notify_remove(struct device *dev) sysfs_remove_link(&swnode->kobj, dev_name(dev)); sysfs_remove_link(&dev->kobj, "software_node"); + + /* + * Drop the device pointer mirrored onto a secondary software node in + * software_node_notify(). For a primary software node the core owns + * fwnode->dev and clears it in device_del(). + */ + if (!device_match_fwnode(dev, &swnode->fwnode) && swnode->fwnode.dev == dev) + swnode->fwnode.dev = NULL; + swnode_put(swnode); if (swnode->managed) { |