diff options
Diffstat (limited to 'include/linux/usb.h')
| -rw-r--r-- | include/linux/usb.h | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/include/linux/usb.h b/include/linux/usb.h index 14933451d21..e6c815590fd 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -378,6 +378,39 @@ 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; +}; + /** * struct usb_device - kernel's representation of a USB device * @devnum: device number; address on a USB bus @@ -435,6 +468,8 @@ 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 U1 (USB 3.0 LPM). + * @u2_params: exit latencies for U2 (USB 3.0 LPM). * * Notes: * Usbcore drivers should not set usbdev->state directly. Instead use @@ -507,6 +542,8 @@ 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; }; #define to_usb_device(d) container_of(d, struct usb_device, dev) |