[PATCH 09/28] thunderbolt: Cache adapter specific capability offset into struct port

[Mika Westerberg <mika.westerberg@linux.intel.com>]

The adapter specific capability either is there or not if the port does
not hold an adapter. Instead of always finding it on-demand we read the
offset just once when the port is initialized.

While there we update the struct port documentation to follow kernel-doc
format.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
---
 drivers/thunderbolt/switch.c     | 4 ++++
 drivers/thunderbolt/tb.c         | 4 ++--
 drivers/thunderbolt/tb.h         | 3 +++
 drivers/thunderbolt/tunnel_pci.c | 9 +++------
 4 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index 1eee2502b5ba..fcafe4095de5 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -585,6 +585,8 @@ static int tb_init_port(struct tb_port *port)
 	if (res)
 		return res;
 
+	port->cap_adap = -ENOENT;
+
 	/* Port 0 is the switch itself and has no PHY. */
 	if (port->config.type == TB_TYPE_PORT && port->port != 0) {
 		cap = tb_port_find_cap(port, TB_PORT_CAP_PHY);
@@ -593,6 +595,8 @@ static int tb_init_port(struct tb_port *port)
 			port->cap_phy = cap;
 		else
 			tb_port_WARN(port, "non switch port without a PHY\n");
+	} else if (port->port != 0) {
+		port->cap_adap = tb_port_find_cap(port, TB_PORT_CAP_ADAP);
 	}
 
 	tb_dump_port(port->sw->tb, &port->config);
diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
index 30e02c716f6c..8e9761d950d6 100644
--- a/drivers/thunderbolt/tb.c
+++ b/drivers/thunderbolt/tb.c
@@ -151,7 +151,7 @@ static struct tb_port *tb_find_unused_down_port(struct tb_switch *sw)
 			continue;
 		if (sw->ports[i].config.type != TB_TYPE_PCIE_DOWN)
 			continue;
-		cap = tb_port_find_cap(&sw->ports[i], TB_PORT_CAP_ADAP);
+		cap = sw->ports[i].cap_adap;
 		if (cap < 0)
 			continue;
 		res = tb_port_read(&sw->ports[i], &data, TB_CFG_PORT, cap, 1);
@@ -197,7 +197,7 @@ static void tb_activate_pcie_devices(struct tb *tb)
 		}
 
 		/* check whether port is already activated */
-		cap = tb_port_find_cap(up_port, TB_PORT_CAP_ADAP);
+		cap = up_port->cap_adap;
 		if (cap < 0)
 			continue;
 		if (tb_port_read(up_port, &data, TB_CFG_PORT, cap, 1))
diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index 3160169389cc..43a1d7dfba73 100644
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -124,6 +124,8 @@ struct tb_switch {
  * @remote: Remote port (%NULL if not connected)
  * @xdomain: Remote host (%NULL if not connected)
  * @cap_phy: Offset, zero if not found
+ * @cap_adap: Offset of the adapter specific capability. Negative if not
+ *	      present.
  * @port: Port number on switch
  * @disabled: Disabled by eeprom
  * @dual_link_port: If the switch is connected using two ports, points
@@ -136,6 +138,7 @@ struct tb_port {
 	struct tb_port *remote;
 	struct tb_xdomain *xdomain;
 	int cap_phy;
+	int cap_adap;
 	u8 port;
 	bool disabled;
 	struct tb_port *dual_link_port;
diff --git a/drivers/thunderbolt/tunnel_pci.c b/drivers/thunderbolt/tunnel_pci.c
index 0637537ea53f..4fae236a4a39 100644
--- a/drivers/thunderbolt/tunnel_pci.c
+++ b/drivers/thunderbolt/tunnel_pci.c
@@ -148,12 +148,9 @@ bool tb_pci_is_invalid(struct tb_pci_tunnel *tunnel)
 static int tb_pci_port_active(struct tb_port *port, bool active)
 {
 	u32 word = active ? 0x80000000 : 0x0;
-	int cap = tb_port_find_cap(port, TB_PORT_CAP_ADAP);
-	if (cap < 0) {
-		tb_port_warn(port, "TB_PORT_CAP_ADAP not found: %d\n", cap);
-		return cap;
-	}
-	return tb_port_write(port, &word, TB_CFG_PORT, cap, 1);
+	if (port->cap_adap < 0)
+		return -ENXIO;
+	return tb_port_write(port, &word, TB_CFG_PORT, port->cap_adap, 1);
 }
 
 /**
-- 
2.20.1