thunderbolt: Scan for downstream switches
Add utility methods tb_port_state and tb_wait_for_port. Add
tb_scan_switch which recursively checks for downstream switches.
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
index f1b6100..3b716fd 100644
--- a/drivers/thunderbolt/tb.c
+++ b/drivers/thunderbolt/tb.c
@@ -11,6 +11,47 @@
#include "tb.h"
#include "tb_regs.h"
+
+/* enumeration & hot plug handling */
+
+
+static void tb_scan_port(struct tb_port *port);
+
+/**
+ * tb_scan_switch() - scan for and initialize downstream switches
+ */
+static void tb_scan_switch(struct tb_switch *sw)
+{
+ int i;
+ for (i = 1; i <= sw->config.max_port_number; i++)
+ tb_scan_port(&sw->ports[i]);
+}
+
+/**
+ * tb_scan_port() - check for and initialize switches below port
+ */
+static void tb_scan_port(struct tb_port *port)
+{
+ struct tb_switch *sw;
+ if (tb_is_upstream_port(port))
+ return;
+ if (port->config.type != TB_TYPE_PORT)
+ return;
+ if (tb_wait_for_port(port, false) <= 0)
+ return;
+ if (port->remote) {
+ tb_port_WARN(port, "port already has a remote!\n");
+ return;
+ }
+ sw = tb_switch_alloc(port->sw->tb, tb_downstream_route(port));
+ if (!sw)
+ return;
+ port->remote = tb_upstream_port(sw);
+ tb_upstream_port(sw)->remote = port;
+ tb_scan_switch(sw);
+}
+
+
/* hotplug handling */
struct tb_hotplug_event {
@@ -134,6 +175,9 @@
if (!tb->root_switch)
goto err_locked;
+ /* Full scan to discover devices added before the driver was loaded. */
+ tb_scan_switch(tb->root_switch);
+
/* Allow tb_handle_hotplug to progress events */
tb->hotplug_active = true;
mutex_unlock(&tb->lock);
