usb: Add "portX/connect_type" attribute to expose usb port's connect type

Some platforms provide usb port connect types through ACPI. This
patch is to add this new attribute to expose these information
to user space.

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb
index b6fbe514a869a311bea16c1918061128c8f9d6dc..c8baaf53594a862fb8be7fadd880cb534de8acea 100644 (file)
--- a/Documentation/ABI/testing/sysfs-bus-usb
+++ b/Documentation/ABI/testing/sysfs-bus-usb
@@ -227,3 +227,12 @@ Contact:   Lan Tianyu <tianyu.lan@intel.com>
 Description:
                The /sys/bus/usb/devices/.../(hub interface)/portX
                is usb port device's sysfs directory.
+
+What:          /sys/bus/usb/devices/.../(hub interface)/portX/connect_type
+Date:          January 2013
+Contact:       Lan Tianyu <tianyu.lan@intel.com>
+Description:
+               Some platforms provide usb port connect types through ACPI.
+               This attribute is to expose these information to user space.
+               The file will read "hotplug", "wired" and "not used" if the
+               information is available, and "unknown" otherwise.

diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
index 3734850120ae65de8d44f1697202cb0f5a409256..fe5959fc021b387a7de72d39dd95a216e728738b 100644 (file)
--- a/drivers/usb/core/port.c
+++ b/drivers/usb/core/port.c
@@ -20,6 +20,48 @@
 
 #include "hub.h"
 
+static const struct attribute_group *port_dev_group[];
+
+static ssize_t show_port_connect_type(struct device *dev,
+       struct device_attribute *attr, char *buf)
+{
+       struct usb_port *port_dev = to_usb_port(dev);
+       char *result;
+
+       switch (port_dev->connect_type) {
+       case USB_PORT_CONNECT_TYPE_HOT_PLUG:
+               result = "hotplug";
+               break;
+       case USB_PORT_CONNECT_TYPE_HARD_WIRED:
+               result = "hardwired";
+               break;
+       case USB_PORT_NOT_USED:
+               result = "not used";
+               break;
+       default:
+               result = "unknown";
+               break;
+       }
+
+       return sprintf(buf, "%s\n", result);
+}
+static DEVICE_ATTR(connect_type, S_IRUGO, show_port_connect_type,
+               NULL);
+
+static struct attribute *port_dev_attrs[] = {
+       &dev_attr_connect_type.attr,
+       NULL,
+};
+
+static struct attribute_group port_dev_attr_grp = {
+       .attrs = port_dev_attrs,
+};
+
+static const struct attribute_group *port_dev_group[] = {
+       &port_dev_attr_grp,
+       NULL,
+};
+
 static void usb_port_device_release(struct device *dev)
 {
        struct usb_port *port_dev = to_usb_port(dev);
@@ -45,6 +87,7 @@ int usb_hub_create_port_device(struct usb_hub *hub, int port1)
 
        hub->ports[port1 - 1] = port_dev;
        port_dev->dev.parent = hub->intfdev;
+       port_dev->dev.groups = port_dev_group;
        port_dev->dev.type = &usb_port_device_type;
        dev_set_name(&port_dev->dev, "port%d", port1);