[PATCH 03/19] thunderbolt: Handle connecting device in place of host properly

[Anthony Wong]

From: Mika Westerberg <mika.westerberg at linux.intel.com>

If the system is suspended and user disconnects cable to another host
and connects it to a Thunderbolt device instead we get a warning from
driver core about adding duplicate sysfs attribute and adding the new
device fails.

Handle this properly so that we first remove the existing XDomain
connection before adding new devices.

Fixes: d1ff70241a27 ("thunderbolt: Add support for XDomain discovery protocol")
Signed-off-by: Mika Westerberg <mika.westerberg at linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko at gmail.com>
Cc: stable at vger.kernel.org
(cherry picked from commit 79fae987518a3aa6c3c7b2e3ad5fe1e4080c12bc)
Signed-off-by: Anthony Wong <anthony.wong at canonical.com>
---
 drivers/thunderbolt/icm.c | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/drivers/thunderbolt/icm.c b/drivers/thunderbolt/icm.c
index ab02d13..1822260 100644
--- a/drivers/thunderbolt/icm.c
+++ b/drivers/thunderbolt/icm.c
@@ -383,6 +383,15 @@ static void remove_switch(struct tb_switch *sw)
 	tb_switch_remove(sw);
 }
 
+static void remove_xdomain(struct tb_xdomain *xd)
+{
+	struct tb_switch *sw;
+
+	sw = tb_to_switch(xd->dev.parent);
+	tb_port_at(xd->route, sw)->xdomain = NULL;
+	tb_xdomain_remove(xd);
+}
+
 static void
 icm_fr_device_connected(struct tb *tb, const struct icm_pkg_header *hdr)
 {
@@ -391,6 +400,7 @@ icm_fr_device_connected(struct tb *tb, const struct icm_pkg_header *hdr)
 	struct tb_switch *sw, *parent_sw;
 	struct icm *icm = tb_priv(tb);
 	bool authorized = false;
+	struct tb_xdomain *xd;
 	u8 link, depth;
 	u64 route;
 	int ret;
@@ -467,6 +477,13 @@ icm_fr_device_connected(struct tb *tb, const struct icm_pkg_header *hdr)
 		tb_switch_put(sw);
 	}
 
+	/* Remove existing XDomain connection if found */
+	xd = tb_xdomain_find_by_link_depth(tb, link, depth);
+	if (xd) {
+		remove_xdomain(xd);
+		tb_xdomain_put(xd);
+	}
+
 	parent_sw = tb_switch_find_by_link_depth(tb, link, depth - 1);
 	if (!parent_sw) {
 		tb_err(tb, "failed to find parent switch for %u.%u\n",
@@ -529,15 +546,6 @@ icm_fr_device_disconnected(struct tb *tb, const struct icm_pkg_header *hdr)
 	tb_switch_put(sw);
 }
 
-static void remove_xdomain(struct tb_xdomain *xd)
-{
-	struct tb_switch *sw;
-
-	sw = tb_to_switch(xd->dev.parent);
-	tb_port_at(xd->route, sw)->xdomain = NULL;
-	tb_xdomain_remove(xd);
-}
-
 static void
 icm_fr_xdomain_connected(struct tb *tb, const struct icm_pkg_header *hdr)
 {
-- 
2.7.4