USB 3.2 specification supports dual-lane for super-speed-plus. USB
devices may operate at different sublink speeds. To avoid using magic
numbers and capture the sublink speed better, introduce the
usb_sublink_speed structure and various sublink speed attribute enum.
See SSP BOS descriptor in USB 3.2 specification section 9.6.2.5
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>
---
Changes in v5:
- Rebase on Felipe's testing/next branch
- Changed Signed-off-by email to match From: email header
Changes in v4:
- None
Changes in v3:
- None
Changes in v2:
- Move to include/linux/usb/ch9.h instead of under uapi
include/linux/usb/ch9.h | 43 +++++++++++++++++++++++++++++++++++++++++
1 file changed, 43 insertions(+)
diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h
index 604c6c514a50..01191649a0ad 100644
--- a/include/linux/usb/ch9.h
+++ b/include/linux/usb/ch9.h
@@ -36,6 +36,49 @@
#include <linux/device.h>
#include <uapi/linux/usb/ch9.h>
+/* USB 3.2 sublink speed attributes */
+
+enum usb_lane_speed_exponent {
+ USB_LSE_BPS = 0,
+ USB_LSE_KBPS = 1,
+ USB_LSE_MBPS = 2,
+ USB_LSE_GBPS = 3,
+};
+
+enum usb_sublink_type {
+ USB_ST_SYMMETRIC_RX = 0,
+ USB_ST_ASYMMETRIC_RX = 1,
+ USB_ST_SYMMETRIC_TX = 2,
+ USB_ST_ASYMMETRIC_TX = 3,
+};
+
+enum usb_link_protocol {
+ USB_LP_SS = 0,
+ USB_LP_SSP = 1,
+};
+
+/**
+ * struct usb_sublink_speed - sublink speed attribute
+ * @id: sublink speed attribute ID (SSID)
+ * @mantissa: lane speed mantissa
+ * @exponent: lane speed exponent
+ * @type: sublink type
+ * @protocol: sublink protocol
+ *
+ * Super-speed-plus supports multiple lanes. Use the sublink speed attributes to
+ * describe the sublink speed.
+ *
+ * See USB 3.2 spec section 9.6.2.6 for super-speed-plus capability for more
+ * information.
+ */
+struct usb_sublink_speed {
+ u8 id;
+ u16 mantissa;
+ enum usb_lane_speed_exponent exponent;
+ enum usb_sublink_type type;
+ enum usb_link_protocol protocol;
+};
+
/**
* usb_ep_type_string() - Returns human readable-name of the endpoint type.
* @ep_type: The endpoint type to return human-readable name for. If it's not
--
2.28.0
