usb: quiet peer failure warning, disable poweroff

In the case where platform firmware has specified conflicting values for
port locations it is confusing and otherwise not helpful to throw a
backtrace.  Instead, include enough information to determine that
firmware has done something wrong and globally disable port poweroff.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
index 62036fa..9347ade 100644 (file)
--- a/drivers/usb/core/port.c
+++ b/drivers/usb/core/port.c
@@ -21,6 +21,8 @@
 
 #include "hub.h"
 
+static int usb_port_block_power_off;
+
 static const struct attribute_group *port_dev_group[];
 
 static ssize_t connect_type_show(struct device *dev,
@@ -142,6 +144,9 @@ static int usb_port_runtime_suspend(struct device *dev)
                        == PM_QOS_FLAGS_ALL)
                return -EAGAIN;
 
+       if (usb_port_block_power_off)
+               return -EBUSY;
+
        usb_autopm_get_interface(intf);
        retval = usb_hub_set_port_power(hdev, hub, port1, false);
        usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
@@ -190,11 +195,19 @@ static int link_peers(struct usb_port *left, struct usb_port *right)
        if (left->peer || right->peer) {
                struct usb_port *lpeer = left->peer;
                struct usb_port *rpeer = right->peer;
-
-               WARN(1, "failed to peer %s and %s (%s -> %p) (%s -> %p)\n",
-                       dev_name(&left->dev), dev_name(&right->dev),
-                       dev_name(&left->dev), lpeer,
-                       dev_name(&right->dev), rpeer);
+               char *method;
+
+               if (left->location && left->location == right->location)
+                       method = "location";
+               else
+                       method = "default";
+
+               pr_warn("usb: failed to peer %s and %s by %s (%s:%s) (%s:%s)\n",
+                       dev_name(&left->dev), dev_name(&right->dev), method,
+                       dev_name(&left->dev),
+                       lpeer ? dev_name(&lpeer->dev) : "none",
+                       dev_name(&right->dev),
+                       rpeer ? dev_name(&rpeer->dev) : "none");
                return -EBUSY;
        }
 
@@ -251,6 +264,7 @@ static void link_peers_report(struct usb_port *left, struct usb_port *right)
                dev_warn(&left->dev, "failed to peer to %s (%d)\n",
                                dev_name(&right->dev), rc);
                pr_warn_once("usb: port power management may be unreliable\n");
+               usb_port_block_power_off = 1;
        }
 }