Merge #1130

1130: USB serial (CDC-ACM) improvements r=Dirbaio a=timokroeger

* Remove unused call management descriptor
* Set flag for supported capabilities

The rp `usb_serial` example still works with windows hosts.

Co-authored-by: Timo Kröger <[email protected]>

1 files changed, 4 insertions, 10 deletions

diff --git a/embassy-usb/src/class/cdc_acm.rs b/embassy-usb/src/class/cdc_acm.rs
index 09bb1cc8d..84db20621 100644
--- a/embassy-usb/src/class/cdc_acm.rs
+++ b/embassy-usb/src/class/cdc_acm.rs
@@ -18,7 +18,6 @@ const CDC_PROTOCOL_NONE: u8 = 0x00;
 
 const CS_INTERFACE: u8 = 0x24;
 const CDC_TYPE_HEADER: u8 = 0x00;
-const CDC_TYPE_CALL_MANAGEMENT: u8 = 0x01;
 const CDC_TYPE_ACM: u8 = 0x02;
 const CDC_TYPE_UNION: u8 = 0x06;
 
@@ -186,7 +185,10 @@ impl<'d, D: Driver<'d>> CdcAcmClass<'d, D> {
             CS_INTERFACE,
             &[
                 CDC_TYPE_ACM, // bDescriptorSubtype
-                0x00,         // bmCapabilities
+                0x02,         // bmCapabilities:
+                              // D1: Device supports the request combination of
+                              // Set_Line_Coding, Set_Control_Line_State, Get_Line_Coding,
+                              // and the Notification Serial_State.
             ],
         );
         alt.descriptor(
@@ -197,14 +199,6 @@ impl<'d, D: Driver<'d>> CdcAcmClass<'d, D> {
                 data_if.into(), // bSubordinateInterface
             ],
         );
-        alt.descriptor(
-            CS_INTERFACE,
-            &[
-                CDC_TYPE_CALL_MANAGEMENT, // bDescriptorSubtype
-                0x00,                     // bmCapabilities
-                data_if.into(),           // bDataInterface
-            ],
-        );
 
         let comm_ep = alt.endpoint_interrupt_in(8, 255);