thunderbolt: Add helper macro to iterate over switch ports

There are quite many places in the driver where we iterate over each
port in the switch. To make it bit more convenient, add a macro that can
be used to iterate over each port and convert existing call sites to use it.

This is based on code by Lukas Wunner.

No functional changes.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

drivers/thunderbolt/icm.c

@@ -1893,14 +1893,12 @@ static int icm_suspend(struct tb *tb)
  */
 static void icm_unplug_children(struct tb_switch *sw)
 {
-	unsigned int i;
+	struct tb_port *port;
 
 	if (tb_route(sw))
 		sw->is_unplugged = true;
 
-	for (i = 1; i <= sw->config.max_port_number; i++) {
-		struct tb_port *port = &sw->ports[i];
-
+	tb_switch_for_each_port(sw, port) {
 		if (port->xdomain)
 			port->xdomain->is_unplugged = true;
 		else if (tb_port_has_remote(port))
@@ -1936,11 +1934,9 @@ static void remove_unplugged_switch(struct tb_switch *sw)
 
 static void icm_free_unplugged_children(struct tb_switch *sw)
 {
-	unsigned int i;
-
-	for (i = 1; i <= sw->config.max_port_number; i++) {
-		struct tb_port *port = &sw->ports[i];
+	struct tb_port *port;
 
+	tb_switch_for_each_port(sw, port) {
 		if (port->xdomain && port->xdomain->is_unplugged) {
 			tb_xdomain_remove(port->xdomain);
 			port->xdomain = NULL;

drivers/thunderbolt/switch.c

@@ -1400,14 +1400,14 @@ static const struct attribute_group *switch_groups[] = {
 static void tb_switch_release(struct device *dev)
 {
 	struct tb_switch *sw = tb_to_switch(dev);
-	int i;
+	struct tb_port *port;
 
 	dma_port_free(sw->dma_port);
 
-	for (i = 1; i <= sw->config.max_port_number; i++) {
-		if (!sw->ports[i].disabled) {
-			ida_destroy(&sw->ports[i].in_hopids);
-			ida_destroy(&sw->ports[i].out_hopids);
+	tb_switch_for_each_port(sw, port) {
+		if (!port->disabled) {
+			ida_destroy(&port->in_hopids);
+			ida_destroy(&port->out_hopids);
 		}
 	}
 
@@ -1869,7 +1869,7 @@ int tb_switch_add(struct tb_switch *sw)
  */
 void tb_switch_remove(struct tb_switch *sw)
 {
-	int i;
+	struct tb_port *port;
 
 	if (sw->rpm) {
 		pm_runtime_get_sync(&sw->dev);
@@ -1877,13 +1877,13 @@ void tb_switch_remove(struct tb_switch *sw)
 	}
 
 	/* port 0 is the switch itself and never has a remote */
-	for (i = 1; i <= sw->config.max_port_number; i++) {
-		if (tb_port_has_remote(&sw->ports[i])) {
-			tb_switch_remove(sw->ports[i].remote->sw);
-			sw->ports[i].remote = NULL;
-		} else if (sw->ports[i].xdomain) {
-			tb_xdomain_remove(sw->ports[i].xdomain);
-			sw->ports[i].xdomain = NULL;
+	tb_switch_for_each_port(sw, port) {
+		if (tb_port_has_remote(port)) {
+			tb_switch_remove(port->remote->sw);
+			port->remote = NULL;
+		} else if (port->xdomain) {
+			tb_xdomain_remove(port->xdomain);
+			port->xdomain = NULL;
 		}
 	}
 
@@ -1903,7 +1903,8 @@ void tb_switch_remove(struct tb_switch *sw)
  */
 void tb_sw_set_unplugged(struct tb_switch *sw)
 {
-	int i;
+	struct tb_port *port;
+
 	if (sw == sw->tb->root_switch) {
 		tb_sw_WARN(sw, "cannot unplug root switch\n");
 		return;
@@ -1913,17 +1914,19 @@ void tb_sw_set_unplugged(struct tb_switch *sw)
 		return;
 	}
 	sw->is_unplugged = true;
-	for (i = 0; i <= sw->config.max_port_number; i++) {
-		if (tb_port_has_remote(&sw->ports[i]))
-			tb_sw_set_unplugged(sw->ports[i].remote->sw);
-		else if (sw->ports[i].xdomain)
-			sw->ports[i].xdomain->is_unplugged = true;
+	tb_switch_for_each_port(sw, port) {
+		if (tb_port_has_remote(port))
+			tb_sw_set_unplugged(port->remote->sw);
+		else if (port->xdomain)
+			port->xdomain->is_unplugged = true;
 	}
 }
 
 int tb_switch_resume(struct tb_switch *sw)
 {
-	int i, err;
+	struct tb_port *port;
+	int err;
+
 	tb_sw_dbg(sw, "resuming switch\n");
 
 	/*
@@ -1971,9 +1974,7 @@ int tb_switch_resume(struct tb_switch *sw)
 		return err;
 
 	/* check for surviving downstream switches */
-	for (i = 1; i <= sw->config.max_port_number; i++) {
-		struct tb_port *port = &sw->ports[i];
-
+	tb_switch_for_each_port(sw, port) {
 		if (!tb_port_has_remote(port) && !port->xdomain)
 			continue;
 
@@ -1997,14 +1998,16 @@ int tb_switch_resume(struct tb_switch *sw)
 
 void tb_switch_suspend(struct tb_switch *sw)
 {
-	int i, err;
+	struct tb_port *port;
+	int err;
+
 	err = tb_plug_events_active(sw, false);
 	if (err)
 		return;
 
-	for (i = 1; i <= sw->config.max_port_number; i++) {
-		if (tb_port_has_remote(&sw->ports[i]))
-			tb_switch_suspend(sw->ports[i].remote->sw);
+	tb_switch_for_each_port(sw, port) {
+		if (tb_port_has_remote(port))
+			tb_switch_suspend(port->remote->sw);
 	}
 
 	tb_lc_set_sleep(sw);

drivers/thunderbolt/tb.c

@@ -61,12 +61,10 @@ static void tb_discover_tunnels(struct tb_switch *sw)
 	struct tb *tb = sw->tb;
 	struct tb_cm *tcm = tb_priv(tb);
 	struct tb_port *port;
-	int i;
 
-	for (i = 1; i <= sw->config.max_port_number; i++) {
+	tb_switch_for_each_port(sw, port) {
 		struct tb_tunnel *tunnel = NULL;
 
-		port = &sw->ports[i];
 		switch (port->config.type) {
 		case TB_TYPE_DP_HDMI_IN:
 			tunnel = tb_tunnel_discover_dp(tb, port);
@@ -95,9 +93,9 @@ static void tb_discover_tunnels(struct tb_switch *sw)
 		list_add_tail(&tunnel->list, &tcm->tunnel_list);
 	}
 
-	for (i = 1; i <= sw->config.max_port_number; i++) {
-		if (tb_port_has_remote(&sw->ports[i]))
-			tb_discover_tunnels(sw->ports[i].remote->sw);
+	tb_switch_for_each_port(sw, port) {
+		if (tb_port_has_remote(port))
+			tb_discover_tunnels(port->remote->sw);
 	}
 }
 
@@ -130,9 +128,10 @@ static void tb_scan_port(struct tb_port *port);
  */
 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]);
+	struct tb_port *port;
+
+	tb_switch_for_each_port(sw, port)
+		tb_scan_port(port);
 }
 
 /**
@@ -263,10 +262,9 @@ static void tb_free_invalid_tunnels(struct tb *tb)
  */
 static void tb_free_unplugged_children(struct tb_switch *sw)
 {
-	int i;
-	for (i = 1; i <= sw->config.max_port_number; i++) {
-		struct tb_port *port = &sw->ports[i];
+	struct tb_port *port;
 
+	tb_switch_for_each_port(sw, port) {
 		if (!tb_port_has_remote(port))
 			continue;
 
@@ -289,10 +287,13 @@ static void tb_free_unplugged_children(struct tb_switch *sw)
 static struct tb_port *tb_find_port(struct tb_switch *sw,
 				    enum tb_port_type type)
 {
-	int i;
-	for (i = 1; i <= sw->config.max_port_number; i++)
-		if (sw->ports[i].config.type == type)
-			return &sw->ports[i];
+	struct tb_port *port;
+
+	tb_switch_for_each_port(sw, port) {
+		if (port->config.type == type)
+			return port;
+	}
+
 	return NULL;
 }
 
@@ -304,18 +305,18 @@ static struct tb_port *tb_find_port(struct tb_switch *sw,
 static struct tb_port *tb_find_unused_port(struct tb_switch *sw,
 					   enum tb_port_type type)
 {
-	int i;
+	struct tb_port *port;
 
-	for (i = 1; i <= sw->config.max_port_number; i++) {
-		if (tb_is_upstream_port(&sw->ports[i]))
+	tb_switch_for_each_port(sw, port) {
+		if (tb_is_upstream_port(port))
 			continue;
-		if (sw->ports[i].config.type != type)
+		if (port->config.type != type)
 			continue;
-		if (!sw->ports[i].cap_adap)
+		if (port->cap_adap)
 			continue;
-		if (tb_port_is_enabled(&sw->ports[i]))
+		if (tb_port_is_enabled(port))
 			continue;
-		return &sw->ports[i];
+		return port;
 	}
 	return NULL;
 }
@@ -734,11 +735,10 @@ static int tb_resume_noirq(struct tb *tb)
 
 static int tb_free_unplugged_xdomains(struct tb_switch *sw)
 {
-	int i, ret = 0;
-
-	for (i = 1; i <= sw->config.max_port_number; i++) {
-		struct tb_port *port = &sw->ports[i];
+	struct tb_port *port;
+	int ret = 0;
 
+	tb_switch_for_each_port(sw, port) {
 		if (tb_is_upstream_port(port))
 			continue;
 		if (port->xdomain && port->xdomain->is_unplugged) {

drivers/thunderbolt/tb.h

@@ -530,6 +530,17 @@ struct tb_switch *tb_switch_find_by_link_depth(struct tb *tb, u8 link,
 struct tb_switch *tb_switch_find_by_uuid(struct tb *tb, const uuid_t *uuid);
 struct tb_switch *tb_switch_find_by_route(struct tb *tb, u64 route);
 
+/**
+ * tb_switch_for_each_port() - Iterate over each switch port
+ * @sw: Switch whose ports to iterate
+ * @p: Port used as iterator
+ *
+ * Iterates over each switch port skipping the control port (port %0).
+ */
+#define tb_switch_for_each_port(sw, p)					\
+	for ((p) = &(sw)->ports[1];					\
+	     (p) <= &(sw)->ports[(sw)->config.max_port_number]; (p)++)
+
 static inline struct tb_switch *tb_switch_get(struct tb_switch *sw)
 {
 	if (sw)

drivers/thunderbolt/xdomain.c

@@ -1404,10 +1404,9 @@ struct tb_xdomain_lookup {
 static struct tb_xdomain *switch_find_xdomain(struct tb_switch *sw,
 	const struct tb_xdomain_lookup *lookup)
 {
-	int i;
+	struct tb_port *port;
 
-	for (i = 1; i <= sw->config.max_port_number; i++) {
-		struct tb_port *port = &sw->ports[i];
+	tb_switch_for_each_port(sw, port) {
 		struct tb_xdomain *xd;
 
 		if (port->xdomain) {