USB Serial: Implement Abstract Control Management

On devices that can assign interrupt IN, bulk IN and bulk OUT endpoints
this change results in the serial interface working out of the box on
Linux and Windows. On Linux it is registered as ttyACM device and on
Windows it is assigned a COM port number.

On devices that cannot assign the interrupt IN this change won't have
any effect.

Implement minimum required interface control requests. Respond with
whatever line coding was set to make terminal programs happy.

Change-Id: Id7d3899d8546e45d7cb4ecc3fe464908cb59e810

1 files changed, 17 insertions, 0 deletions

diff --git a/firmware/export/usb_ch9.h b/firmware/export/usb_ch9.h
index c11775b893..659bcca101 100644
--- a/firmware/export/usb_ch9.h
+++ b/firmware/export/usb_ch9.h
@@ -391,6 +391,23 @@ struct usb_debug_descriptor {
 } __attribute__((packed));
 
 /*-------------------------------------------------------------------------*/
+
+/* USB_DT_INTERFACE_ASSOCIATION: groups interfaces */
+struct usb_interface_assoc_descriptor {
+        uint8_t  bLength;
+        uint8_t  bDescriptorType;
+
+        uint8_t  bFirstInterface;
+        uint8_t  bInterfaceCount;
+        uint8_t  bFunctionClass;
+        uint8_t  bFunctionSubClass;
+        uint8_t  bFunctionProtocol;
+        uint8_t  iFunction;
+} __attribute__ ((packed));
+
+#define USB_DT_INTERFACE_ASSOCIATION_SIZE       8
+
+/*-------------------------------------------------------------------------*/
 /* USB 2.0 defines three speeds, here's how Linux identifies them */
 
 enum usb_device_speed {