static void tb_handle_hotplug()

in tb.c [1186:1288]

• 83 lines of code
• 16 McCabe index (conditional complexity)

static void tb_handle_hotplug(struct work_struct *work)
{
	struct tb_hotplug_event *ev = container_of(work, typeof(*ev), work);
	struct tb *tb = ev->tb;
	struct tb_cm *tcm = tb_priv(tb);
	struct tb_switch *sw;
	struct tb_port *port;

	/* Bring the domain back from sleep if it was suspended */
	pm_runtime_get_sync(&tb->dev);

	mutex_lock(&tb->lock);
	if (!tcm->hotplug_active)
		goto out; /* during init, suspend or shutdown */

	sw = tb_switch_find_by_route(tb, ev->route);
	if (!sw) {
		tb_warn(tb,
			"hotplug event from non existent switch %llx:%x (unplug: %d)\n",
			ev->route, ev->port, ev->unplug);
		goto out;
	}
	if (ev->port > sw->config.max_port_number) {
		tb_warn(tb,
			"hotplug event from non existent port %llx:%x (unplug: %d)\n",
			ev->route, ev->port, ev->unplug);
		goto put_sw;
	}
	port = &sw->ports[ev->port];
	if (tb_is_upstream_port(port)) {
		tb_dbg(tb, "hotplug event for upstream port %llx:%x (unplug: %d)\n",
		       ev->route, ev->port, ev->unplug);
		goto put_sw;
	}

	pm_runtime_get_sync(&sw->dev);

	if (ev->unplug) {
		tb_retimer_remove_all(port);

		if (tb_port_has_remote(port)) {
			tb_port_dbg(port, "switch unplugged\n");
			tb_sw_set_unplugged(port->remote->sw);
			tb_free_invalid_tunnels(tb);
			tb_remove_dp_resources(port->remote->sw);
			tb_switch_tmu_disable(port->remote->sw);
			tb_switch_unconfigure_link(port->remote->sw);
			tb_switch_lane_bonding_disable(port->remote->sw);
			tb_switch_remove(port->remote->sw);
			port->remote = NULL;
			if (port->dual_link_port)
				port->dual_link_port->remote = NULL;
			/* Maybe we can create another DP tunnel */
			tb_tunnel_dp(tb);
		} else if (port->xdomain) {
			struct tb_xdomain *xd = tb_xdomain_get(port->xdomain);

			tb_port_dbg(port, "xdomain unplugged\n");
			/*
			 * Service drivers are unbound during
			 * tb_xdomain_remove() so setting XDomain as
			 * unplugged here prevents deadlock if they call
			 * tb_xdomain_disable_paths(). We will tear down
			 * all the tunnels below.
			 */
			xd->is_unplugged = true;
			tb_xdomain_remove(xd);
			port->xdomain = NULL;
			__tb_disconnect_xdomain_paths(tb, xd, -1, -1, -1, -1);
			tb_xdomain_put(xd);
			tb_port_unconfigure_xdomain(port);
		} else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) {
			tb_dp_resource_unavailable(tb, port);
		} else {
			tb_port_dbg(port,
				   "got unplug event for disconnected port, ignoring\n");
		}
	} else if (port->remote) {
		tb_port_dbg(port, "got plug event for connected port, ignoring\n");
	} else {
		if (tb_port_is_null(port)) {
			tb_port_dbg(port, "hotplug: scanning\n");
			tb_scan_port(port);
			if (!port->remote)
				tb_port_dbg(port, "hotplug: no switch found\n");
		} else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) {
			tb_dp_resource_available(tb, port);
		}
	}

	pm_runtime_mark_last_busy(&sw->dev);
	pm_runtime_put_autosuspend(&sw->dev);

put_sw:
	tb_switch_put(sw);
out:
	mutex_unlock(&tb->lock);

	pm_runtime_mark_last_busy(&tb->dev);
	pm_runtime_put_autosuspend(&tb->dev);

	kfree(ev);
}