This patch adds device connection parsing in of_platform_populate().
TODO:
- How to free the devcon memories?
- How to remove the devcon instances?
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda...@renesas.com>
---
drivers/of/platform.c | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/of.h | 1 +
2 files changed, 67 insertions(+)
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index c00d81d..41c018d 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -17,6 +17,7 @@
#include <linux/slab.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
+#include <linux/of_graph.h>
#include <linux/of_iommu.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
@@ -326,6 +327,63 @@ static const struct of_dev_auxdata *of_dev_lookup(const
struct of_dev_auxdata *l
return NULL;
}
+static int of_parse_device_connection(struct device_node *np)
+{
+ struct device_node *child_ep, *parent, *remote_parent;
+ struct platform_device *pdev, *remote_pdev;
+ struct device_connection *devcon = NULL;
+ const char *id;
+
+ if (of_node_check_flag(np, OF_DEVICE_CONNECTED)) {
+ pr_debug("%s() - skipping %pOF, already device connected\n",
+ __func__, np);
+ return 0;
+ }
+
+ of_node_set_flag(np, OF_DEVICE_CONNECTED);
+
+ for_each_endpoint_of_node(np, child_ep) {
+ if (of_property_read_string(child_ep, "device-connection-id",
+ &id) < 0)
+ continue;
+
+ remote_parent = of_graph_get_remote_port_parent(child_ep);
+ if (!remote_parent)
+ return 0;
+
+ parent = of_graph_get_port_parent(child_ep);
+ if (!parent)
+ return 0;
+
+ pdev = of_find_device_by_node(parent);
+ if (!pdev)
+ return 0;
+
+ /*
+ * WARN_ON in really_probe() may happen if devm_kzalloc is
+ * used. TODO: How to free this?
+ */
+ devcon = kzalloc(sizeof(*devcon), GFP_KERNEL);
+ if (!devcon)
+ return -ENOMEM;
+
+ devcon->id = id;
+ remote_pdev = of_find_device_by_node(remote_parent);
+ if (!remote_pdev) {
+ kfree(devcon);
+ return 0;
+ }
+
+ devcon->endpoint[0] = dev_name(&pdev->dev);
+ devcon->endpoint[1] = dev_name(&remote_pdev->dev);
+
+ /* TODO: How to remove the connection? */
+ device_connection_add(devcon);
+ }
+
+ return 0;
+}
+
/**
* of_platform_bus_create() - Create a device for a node and its children.
* @bus: device node of the bus to instantiate
@@ -477,6 +535,14 @@ int of_platform_populate(struct device_node *root,
}
of_node_set_flag(root, OF_POPULATED_BUS);
+ for_each_child_of_node(root, child) {
+ rc = of_parse_device_connection(child);
+ if (rc) {
+ of_node_put(child);
+ break;
+ }
+ }
+
of_node_put(root);
return rc;
}
diff --git a/include/linux/of.h b/include/linux/of.h
index 4d25e4f..30aa103 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -143,6 +143,7 @@ static inline void of_node_put(struct device_node *node) { }
#define OF_DETACHED 2 /* node has been detached from the device tree */
#define OF_POPULATED 3 /* device already created for the node */
#define OF_POPULATED_BUS 4 /* of_platform_populate recursed to children
of this node */
+#define OF_DEVICE_CONNECTED 5 /* checked devcon on of_platform_populate */
#define OF_BAD_ADDR ((u64)-1)
--
1.9.1
