1 files changed, 56 insertions, 0 deletions
diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h
new file mode 100644
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+++ b/include/linux/usb/ch9.h
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This file holds USB constants and structures that are needed for
+ * USB device APIs.  These are used by the USB device model, which is
+ * defined in chapter 9 of the USB 2.0 specification and in the
+ * Wireless USB 1.0 (spread around).  Linux has several APIs in C that
+ * need these:
+ *
+ * - the host side Linux-USB kernel driver API;
+ * - the "usbfs" user space API; and
+ * - the Linux "gadget" device/peripheral side driver API.
+ *
+ * USB 2.0 adds an additional "On The Go" (OTG) mode, which lets systems
+ * act either as a USB host or as a USB device.  That means the host and
+ * device side APIs benefit from working well together.
+ *
+ * There's also "Wireless USB", using low power short range radios for
+ * peripheral interconnection but otherwise building on the USB framework.
+ *
+ * Note all descriptors are declared '__attribute__((packed))' so that:
+ *
+ * [a] they never get padded, either internally (USB spec writers
+ *     probably handled that) or externally;
+ *
+ * [b] so that accessing bigger-than-a-bytes fields will never
+ *     generate bus errors on any platform, even when the location of
+ *     its descriptor inside a bundle isn't "naturally aligned", and
+ *
+ * [c] for consistency, removing all doubt even when it appears to
+ *     someone that the two other points are non-issues for that
+ *     particular descriptor type.
+ */
+#ifndef __LINUX_USB_CH9_H
+#define __LINUX_USB_CH9_H
+
+#include <uapi/linux/usb/ch9.h>
+
+/* USB 3.2 SuperSpeed Plus phy signaling rate generation and lane count */
+
+enum usb_ssp_rate {
+	USB_SSP_GEN_UNKNOWN = 0,
+	USB_SSP_GEN_2x1,
+	USB_SSP_GEN_1x2,
+	USB_SSP_GEN_2x2,
+};
+
+extern const char *usb_speed_string(enum usb_device_speed speed);
+
+/**
+ * usb_speed_by_string() - Get speed from human readable name.
+ * @string: The human readable name for the speed. If it is not one of known
+ *   names, USB_SPEED_UNKNOWN will be returned.
+ */
+enum usb_device_speed usb_speed_by_string(const char *string);
+
+#endif /* __LINUX_USB_CH9_H */