@@ -157,6 +157,11 @@ int coresight_add_sysfs_link(struct coresight_sysfs_link *info);
void coresight_remove_sysfs_link(struct coresight_sysfs_link *info);
int coresight_create_conns_sysfs_group(struct coresight_device *csdev);
void coresight_remove_conns_sysfs_group(struct coresight_device *csdev);
+int coresight_make_links(struct coresight_device *orig,
+ struct coresight_connection *conn,
+ struct coresight_device *target);
+void coresight_remove_links(struct coresight_device *orig,
+ struct coresight_connection *conn);
#ifdef CONFIG_CORESIGHT_SOURCE_ETM3X
extern int etm_readl_cp14(u32 off, unsigned int *val);
@@ -122,3 +122,83 @@ void coresight_remove_sysfs_link(struct coresight_sysfs_link *info)
info->orig->nr_links--;
info->target->nr_links--;
}
+
+/*
+ * coresight_make_links: Make a link for a connection from a @orig
+ * device to @target, represented by @conn.
+ *
+ * e.g, for devOrig[output_X] -> devTarget[input_Y] is represented
+ * as two symbolic links :
+ *
+ * /sys/.../devOrig/out:X -> /sys/.../devTarget/
+ * /sys/.../devTarget/in:Y -> /sys/.../devOrig/
+ *
+ * The link names are allocated for a device where it appears. i.e, the
+ * "out" link on the master and "in" link on the slave device.
+ * The link info is stored in the connection record for avoiding
+ * the reconstruction of names for removal.
+ */
+int coresight_make_links(struct coresight_device *orig,
+ struct coresight_connection *conn,
+ struct coresight_device *target)
+{
+ int ret = -ENOMEM;
+ char *outs = NULL, *ins = NULL;
+ struct coresight_sysfs_link *link = NULL;
+
+ do {
+ outs = devm_kasprintf(&orig->dev, GFP_KERNEL,
+ "out:%d", conn->outport);
+ if (!outs)
+ break;
+ ins = devm_kasprintf(&target->dev, GFP_KERNEL,
+ "in:%d", conn->child_port);
+ if (!ins)
+ break;
+ link = devm_kzalloc(&orig->dev,
+ sizeof(struct coresight_sysfs_link),
+ GFP_KERNEL);
+ if (!link)
+ break;
+
+ link->orig = orig;
+ link->target = target;
+ link->orig_name = outs;
+ link->target_name = ins;
+
+ ret = coresight_add_sysfs_link(link);
+ if (ret)
+ break;
+
+ conn->link = link;
+
+ /*
+ * Install the device connection. This also indicates that
+ * the links are operational on both ends.
+ */
+ conn->child_dev = target;
+ return 0;
+ } while (0);
+
+ return ret;
+}
+
+/*
+ * coresight_remove_links: Remove the sysfs links for a given connection @conn,
+ * from @orig device to @target device. See coresight_make_links() for more
+ * details.
+ */
+void coresight_remove_links(struct coresight_device *orig,
+ struct coresight_connection *conn)
+{
+ if (!orig || !conn->link)
+ return;
+
+ coresight_remove_sysfs_link(conn->link);
+
+ devm_kfree(&conn->child_dev->dev, conn->link->target_name);
+ devm_kfree(&orig->dev, conn->link->orig_name);
+ devm_kfree(&orig->dev, conn->link);
+ conn->link = NULL;
+ conn->child_dev = NULL;
+}
@@ -1031,7 +1031,7 @@ static void coresight_device_release(struct device *dev)
static int coresight_orphan_match(struct device *dev, void *data)
{
- int i;
+ int i, ret = 0;
bool still_orphan = false;
struct coresight_device *csdev, *i_csdev;
struct coresight_connection *conn;
@@ -1056,19 +1056,23 @@ static int coresight_orphan_match(struct device *dev, void *data)
/* We have found at least one orphan connection */
if (conn->child_dev == NULL) {
/* Does it match this newly added device? */
- if (conn->child_fwnode == csdev->dev.fwnode)
- conn->child_dev = csdev;
- else
+ if (conn->child_fwnode == csdev->dev.fwnode) {
+ ret = coresight_make_links(i_csdev,
+ conn, csdev);
+ if (ret)
+ return ret;
+ } else {
/* This component still has an orphan */
still_orphan = true;
+ }
}
}
i_csdev->orphan = still_orphan;
/*
- * Returning '0' ensures that all known component on the
- * bus will be checked.
+ * Returning '0' in case we didn't encounter any error,
+ * ensures that all known component on the bus will be checked.
*/
return 0;
}
@@ -1082,15 +1086,21 @@ static int coresight_fixup_orphan_conns(struct coresight_device *csdev)
static int coresight_fixup_device_conns(struct coresight_device *csdev)
{
- int i;
+ int i, ret = 0;
for (i = 0; i < csdev->pdata->nr_outport; i++) {
struct coresight_connection *conn = &csdev->pdata->conns[i];
conn->child_dev =
coresight_find_csdev_by_fwnode(conn->child_fwnode);
- if (!conn->child_dev)
+ if (conn->child_dev) {
+ ret = coresight_make_links(csdev, conn,
+ conn->child_dev);
+ if (ret)
+ break;
+ } else {
csdev->orphan = true;
+ }
}
return 0;
@@ -1121,7 +1131,7 @@ static int coresight_remove_match(struct device *dev, void *data)
if (csdev->dev.fwnode == conn->child_fwnode) {
iterator->orphan = true;
- conn->child_dev = NULL;
+ coresight_remove_links(iterator, conn);
/*
* Drop the reference to the handle for the remote
* device acquired in parsing the connections from
@@ -1215,13 +1225,23 @@ void coresight_release_platform_data(struct coresight_device *csdev,
struct coresight_platform_data *pdata)
{
int i;
+ struct coresight_connection *conns = pdata->conns;
for (i = 0; i < pdata->nr_outport; i++) {
- if (pdata->conns[i].child_fwnode) {
- fwnode_handle_put(pdata->conns[i].child_fwnode);
+ /* If we have made the links, remove them now */
+ if (csdev && conns[i].child_dev)
+ coresight_remove_links(csdev, &conns[i]);
+ /*
+ * Drop the refcount and clear the handle as this device
+ * is going away
+ */
+ if (conns[i].child_fwnode) {
+ fwnode_handle_put(conns[i].child_fwnode);
pdata->conns[i].child_fwnode = NULL;
}
}
+ if (csdev)
+ coresight_remove_conns_sysfs_group(csdev);
}
struct coresight_device *coresight_register(struct coresight_desc *desc)
@@ -1303,7 +1323,9 @@ struct coresight_device *coresight_register(struct coresight_desc *desc)
mutex_lock(&coresight_mutex);
- ret = coresight_fixup_device_conns(csdev);
+ ret = coresight_create_conns_sysfs_group(csdev);
+ if (!ret)
+ ret = coresight_fixup_device_conns(csdev);
if (!ret)
ret = coresight_fixup_orphan_conns(csdev);
if (!ret)
@@ -140,12 +140,14 @@ struct coresight_desc {
* @chid_fwnode: remote component's fwnode handle.
* @child_dev: a @coresight_device representation of the component
connected to @outport.
+ * @link: Representation of the connection as a sysfs link.
*/
struct coresight_connection {
int outport;
int child_port;
struct fwnode_handle *child_fwnode;
struct coresight_device *child_dev;
+ struct coresight_sysfs_link *link;
};
/**