1 files changed, 60 insertions, 0 deletions

diff --git a/include/linux/usb.h b/include/linux/usb.h
index 14933451d21d..c19297a8779c 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -378,6 +378,45 @@ enum usb_device_removable {
         USB_DEVICE_FIXED,
 };
 
+/*
+ * USB 3.0 Link Power Management (LPM) parameters.
+ *
+ * PEL and SEL are USB 3.0 Link PM latencies for device-initiated LPM exit.
+ * MEL is the USB 3.0 Link PM latency for host-initiated LPM exit.
+ * All three are stored in nanoseconds.
+ */
+struct usb3_lpm_parameters {
+        /*
+         * Maximum exit latency (MEL) for the host to send a packet to the
+         * device (either a Ping for isoc endpoints, or a data packet for
+         * interrupt endpoints), the hubs to decode the packet, and for all hubs
+         * in the path to transition the links to U0.
+         */
+        unsigned int mel;
+        /*
+         * Maximum exit latency for a device-initiated LPM transition to bring
+         * all links into U0.  Abbreviated as "PEL" in section 9.4.12 of the USB
+         * 3.0 spec, with no explanation of what "P" stands for.  "Path"?
+         */
+        unsigned int pel;
+
+        /*
+         * The System Exit Latency (SEL) includes PEL, and three other
+         * latencies.  After a device initiates a U0 transition, it will take
+         * some time from when the device sends the ERDY to when it will finally
+         * receive the data packet.  Basically, SEL should be the worse-case
+         * latency from when a device starts initiating a U0 transition to when
+         * it will get data.
+         */
+        unsigned int sel;
+        /*
+         * The idle timeout value that is currently programmed into the parent
+         * hub for this device.  When the timer counts to zero, the parent hub
+         * will initiate an LPM transition to either U1 or U2.
+         */
+        int timeout;
+};
+
 /**
  * struct usb_device - kernel's representation of a USB device
  * @devnum: device number; address on a USB bus
@@ -435,6 +474,12 @@ enum usb_device_removable {
  *      specific data for the device.
  * @slot_id: Slot ID assigned by xHCI
  * @removable: Device can be physically removed from this port
+ * @u1_params: exit latencies for USB3 U1 LPM state, and hub-initiated timeout.
+ * @u2_params: exit latencies for USB3 U2 LPM state, and hub-initiated timeout.
+ * @lpm_disable_count: Ref count used by usb_disable_lpm() and usb_enable_lpm()
+ *      to keep track of the number of functions that require USB 3.0 Link Power
+ *      Management to be disabled for this usb_device.  This count should only
+ *      be manipulated by those functions, with the bandwidth_mutex is held.
  *
  * Notes:
  * Usbcore drivers should not set usbdev->state directly.  Instead use
@@ -481,6 +526,7 @@ struct usb_device {
         unsigned lpm_capable:1;
         unsigned usb2_hw_lpm_capable:1;
         unsigned usb2_hw_lpm_enabled:1;
+        unsigned usb3_lpm_enabled:1;
         int string_langid;
 
         /* static strings from the device */
@@ -507,6 +553,10 @@ struct usb_device {
         struct wusb_dev *wusb_dev;
         int slot_id;
         enum usb_device_removable removable;
+        struct usb3_lpm_parameters u1_params;
+        struct usb3_lpm_parameters u2_params;
+        unsigned lpm_disable_count;
+        unsigned hub_initiated_lpm_disable_count;
 };
 #define to_usb_device(d) container_of(d, struct usb_device, dev)
 
@@ -542,6 +592,12 @@ extern void usb_autopm_put_interface_async(struct usb_interface *intf);
 extern void usb_autopm_get_interface_no_resume(struct usb_interface *intf);
 extern void usb_autopm_put_interface_no_suspend(struct usb_interface *intf);
 
+extern int usb_disable_lpm(struct usb_device *udev);
+extern void usb_enable_lpm(struct usb_device *udev);
+/* Same as above, but these functions lock/unlock the bandwidth_mutex. */
+extern int usb_unlocked_disable_lpm(struct usb_device *udev);
+extern void usb_unlocked_enable_lpm(struct usb_device *udev);
+
 static inline void usb_mark_last_busy(struct usb_device *udev)
 {
         pm_runtime_mark_last_busy(&udev->dev);
@@ -842,6 +898,9 @@ struct usbdrv_wrap {
  *      for interfaces bound to this driver.
  * @soft_unbind: if set to 1, the USB core will not kill URBs and disable
  *      endpoints before calling the driver's disconnect method.
+ * @disable_hub_initiated_lpm: if set to 0, the USB core will not allow hubs
+ *      to initiate lower power link state transitions when an idle timeout
+ *      occurs.  Device-initiated USB 3.0 link PM will still be allowed.
  *
  * USB interface drivers must provide a name, probe() and disconnect()
  * methods, and an id_table.  Other driver fields are optional.
@@ -882,6 +941,7 @@ struct usb_driver {
         struct usbdrv_wrap drvwrap;
         unsigned int no_dynamic_id:1;
         unsigned int supports_autosuspend:1;
+        unsigned int disable_hub_initiated_lpm:1;
         unsigned int soft_unbind:1;
 };
 #define to_usb_driver(d) container_of(d, struct usb_driver, drvwrap.driver)