ACPI identifies peer ports by setting their 'group_token' and 'group_position'
_PLD data to the same value. If a platform has tier mismatch (see Appendix D
figure 131 in the xhci spec), ACPI can override the default peer port
association (for internal hubs).
Location data is cached as an opaque cookie in usb_port_location data.
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
drivers/usb/core/hub.h | 6 +++
drivers/usb/core/port.c | 96 +++++++++++++++++++++++++++++++++++++++++++
drivers/usb/core/usb-acpi.c | 35 +++++++++++++---
drivers/usb/core/usb.h | 2 +
4 files changed, 131 insertions(+), 8 deletions(-)
diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h
index b5efc713498e..2ba10798c943 100644
--- a/drivers/usb/core/hub.h
+++ b/drivers/usb/core/hub.h
@@ -76,6 +76,10 @@ struct usb_hub {
struct usb_port **ports;
};
+struct usb_port_location {
+ u32 cookie;
+};
+
/**
* struct usb port - kernel's representation of a usb port
* @child: usb device attatched to the port
@@ -83,6 +87,7 @@ struct usb_hub {
* @port_owner: port's owner
* @peer: related usb2 and usb3 ports (share the same connector)
* @connect_type: port's connect type
+ * @location: opaque representation of platform connector location
* @portnum: port index num based one
* @power_is_on: port's power state
* @did_runtime_put: port has done pm_runtime_put().
@@ -93,6 +98,7 @@ struct usb_port {
struct dev_state *port_owner;
struct usb_port *peer;
enum usb_port_connect_type connect_type;
+ struct usb_port_location location;
u8 portnum;
unsigned power_is_on:1;
unsigned did_runtime_put:1;
diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
index 7fd22020d7ee..8fae3cd03305 100644
--- a/drivers/usb/core/port.c
+++ b/drivers/usb/core/port.c
@@ -149,11 +149,14 @@ struct device_type usb_port_device_type = {
static struct usb_port *find_peer_port(struct usb_hub *hub, int port1)
{
- struct usb_device *hdev = hub->hdev;
+ struct usb_device *hdev = hub ? hub->hdev : NULL;
struct usb_device *peer_hdev;
struct usb_port *peer = NULL;
struct usb_hub *peer_hub;
+ if (!hub)
+ return NULL;
+
/* set the default peer port for root hubs. Platform firmware
* can later fix this up if tier-mismatch is present. Assumes
* the primary_hcd is usb2.0 and registered first
@@ -193,6 +196,97 @@ static struct usb_port *find_peer_port(struct usb_hub *hub, int port1)
return peer;
}
+static void reset_peer(struct usb_port *port_dev, struct usb_port *peer)
+{
+ if (!peer)
+ return;
+
+ spin_lock(&peer_lock);
+ if (port_dev->peer)
+ put_device(&port_dev->peer->dev);
+ if (peer->peer)
+ put_device(&peer->peer->dev);
+ port_dev->peer = peer;
+ peer->peer = port_dev;
+ get_device(&peer->dev);
+ get_device(&port_dev->dev);
+ spin_unlock(&peer_lock);
+}
+
+/* assumes that location data is only set for external connectors and that
+ * external hubs never have tier mismatch
+ */
+static int redo_find_peer_port(struct device *dev, void *data)
+{
+ struct usb_port *port_dev = to_usb_port(dev);
+
+ if (is_usb_port(dev)) {
+ struct usb_device *hdev = to_usb_device(dev->parent->parent);
+ struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
+ int port1 = port_dev->portnum;
+ struct usb_port *peer;
+
+ peer = find_peer_port(hub, port1);
+ reset_peer(port_dev, peer);
+ }
+
+ return device_for_each_child(dev, NULL, redo_find_peer_port);
+}
+
+static int pair_port(struct device *dev, void *data)
+{
+ struct usb_port *peer = data;
+ struct usb_port *port_dev = to_usb_port(dev);
+
+ if (!is_usb_port(dev)
+ || port_dev->location.cookie != peer->location.cookie)
+ return device_for_each_child(dev, peer, pair_port);
+
+ dev_dbg(dev->parent->parent, "port%d peer = %s port%d (by location)\n",
+ port_dev->portnum, dev_name(peer->dev.parent->parent),
+ peer->portnum);
+ if (port_dev->peer != peer) {
+ /* Sigh, tier mismatch has invalidated our ancestry.
+ * This should not be too onerous even in deep hub
+ * topologies as we will discover tier mismatch early
+ * (after platform internal hubs have been enumerated),
+ * before external hubs are probed.
+ */
+ reset_peer(port_dev, peer);
+ device_for_each_child(dev, NULL, redo_find_peer_port);
+ }
+
+ return true;
+}
+
+void usb_set_hub_port_location(struct usb_device *hdev, int port1,
+ u32 cookie)
+{
+ struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
+ struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
+ struct usb_hcd *peer_hcd = hcd->shared_hcd;
+ struct usb_device *peer_hdev;
+ struct usb_port *port_dev;
+
+ if (cookie == 0)
+ return;
+
+ if (!hub)
+ return;
+
+ port_dev = hub->ports[port1 - 1];
+ port_dev->location.cookie = cookie;
+
+ /* see if a port with the same location data exists in a peer
+ * usb domain
+ */
+ if (!peer_hcd)
+ return;
+
+ peer_hdev = peer_hcd->self.root_hub;
+ device_for_each_child(&peer_hdev->dev, port_dev, pair_port);
+}
+
int usb_hub_create_port_device(struct usb_hub *hub, int port1)
{
struct usb_port *port_dev, *peer;
diff --git a/drivers/usb/core/usb-acpi.c b/drivers/usb/core/usb-acpi.c
index 4e243c37f17f..e957c5216ebe 100644
--- a/drivers/usb/core/usb-acpi.c
+++ b/drivers/usb/core/usb-acpi.c
@@ -18,7 +18,7 @@
#include <linux/usb/hcd.h>
#include <acpi/acpi_bus.h>
-#include "usb.h"
+#include "hub.h"
/**
* usb_acpi_power_manageable - check whether usb port has
@@ -42,6 +42,19 @@ bool usb_acpi_power_manageable(struct usb_device *hdev, int index)
}
EXPORT_SYMBOL_GPL(usb_acpi_power_manageable);
+static void usb_acpi_check_port_peer(struct usb_device *hdev,
+ acpi_handle *handle, int port1,
+ struct acpi_pld_info *pld)
+{
+ if (!pld)
+ return;
+
+ #define USB_ACPI_LOCATION_VALID (1 << 31)
+ usb_set_hub_port_location(hdev, port1, USB_ACPI_LOCATION_VALID
+ | pld->group_token << 8
+ | pld->group_position);
+}
+
/**
* usb_acpi_set_power_state - control usb port's power via acpi power
* resource
@@ -83,12 +96,11 @@ int usb_acpi_set_power_state(struct usb_device *hdev, int index, bool enable)
EXPORT_SYMBOL_GPL(usb_acpi_set_power_state);
static int usb_acpi_check_port_connect_type(struct usb_device *hdev,
- acpi_handle handle, int port1)
+ acpi_handle handle, int port1, struct acpi_pld_info *pld)
{
acpi_status status;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *upc;
- struct acpi_pld_info *pld;
int ret = 0;
/*
@@ -99,8 +111,7 @@ static int usb_acpi_check_port_connect_type(struct usb_device *hdev,
* a usb device is directly hard-wired to the port. If no visible and
* no connectable, the port would be not used.
*/
- status = acpi_get_physical_device_location(handle, &pld);
- if (ACPI_FAILURE(status))
+ if (!pld)
return -ENODEV;
status = acpi_evaluate_object(handle, "_UPC", NULL, &buffer);
@@ -122,7 +133,6 @@ static int usb_acpi_check_port_connect_type(struct usb_device *hdev,
usb_set_hub_port_connect_type(hdev, port1, USB_PORT_NOT_USED);
out:
- ACPI_FREE(pld);
kfree(upc);
return ret;
}
@@ -179,6 +189,9 @@ static int usb_acpi_find_device(struct device *dev, acpi_handle *handle)
return -ENODEV;
return 0;
} else if (is_usb_port(dev)) {
+ struct acpi_pld_info *pld;
+ acpi_status status;
+
sscanf(dev_name(dev), "port%d", &port_num);
/* Get the struct usb_device point of port's hub */
udev = to_usb_device(dev->parent->parent);
@@ -209,7 +222,15 @@ static int usb_acpi_find_device(struct device *dev, acpi_handle *handle)
if (!*handle)
return -ENODEV;
}
- usb_acpi_check_port_connect_type(udev, *handle, port_num);
+
+ status = acpi_get_physical_device_location(*handle, &pld);
+ if (ACPI_FAILURE(status))
+ pld = NULL;
+
+ usb_acpi_check_port_connect_type(udev, *handle, port_num, pld);
+ usb_acpi_check_port_peer(udev, *handle, port_num, pld);
+
+ ACPI_FREE(pld);
} else
return -ENODEV;
diff --git a/drivers/usb/core/usb.h b/drivers/usb/core/usb.h
index c49383669cd8..b80785106b27 100644
--- a/drivers/usb/core/usb.h
+++ b/drivers/usb/core/usb.h
@@ -184,6 +184,8 @@ extern enum usb_port_connect_type
usb_get_hub_port_connect_type(struct usb_device *hdev, int port1);
extern void usb_set_hub_port_connect_type(struct usb_device *hdev, int port1,
enum usb_port_connect_type type);
+extern void usb_set_hub_port_location(struct usb_device *hdev, int port1,
+ u32 cookie);
extern void usb_hub_adjust_deviceremovable(struct usb_device *hdev,
struct usb_hub_descriptor *desc);
--
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