usb: make max interface count configurable at compile time.

2 files changed, 10 insertions, 4 deletions

diff --git a/embassy-usb/src/builder.rs b/embassy-usb/src/builder.rs
index d1cbf674b..d89fc4017 100644
--- a/embassy-usb/src/builder.rs
+++ b/embassy-usb/src/builder.rs
@@ -308,7 +308,10 @@ impl<'a, 'd, D: Driver<'d>> FunctionBuilder<'a, 'd, D> {
         };
 
         if self.builder.interfaces.push(iface).is_err() {
-            panic!("max interface count reached")
+            panic!(
+                "embassy-usb: interface list full. Increase the `max_interface_count` compile-time setting. Current value: {}",
+                MAX_INTERFACE_COUNT
+            )
         }
 
         InterfaceBuilder {
diff --git a/embassy-usb/src/lib.rs b/embassy-usb/src/lib.rs
index aec18524b..f8983318e 100644
--- a/embassy-usb/src/lib.rs
+++ b/embassy-usb/src/lib.rs
@@ -16,10 +16,16 @@ mod descriptor_reader;
 pub mod msos;
 pub mod types;
 
+mod config {
+    #![allow(unused)]
+    include!(concat!(env!("OUT_DIR"), "/config.rs"));
+}
+
 use embassy_futures::select::{select, Either};
 use heapless::Vec;
 
 pub use crate::builder::{Builder, Config};
+use crate::config::*;
 use crate::control::*;
 use crate::descriptor::*;
 use crate::descriptor_reader::foreach_endpoint;
@@ -71,9 +77,6 @@ pub const CONFIGURATION_NONE: u8 = 0;
 /// The bConfiguration value for the single configuration supported by this device.
 pub const CONFIGURATION_VALUE: u8 = 1;
 
-/// Maximum interface count, configured at compile time.
-pub const MAX_INTERFACE_COUNT: usize = 4;
-
 const STRING_INDEX_MANUFACTURER: u8 = 1;
 const STRING_INDEX_PRODUCT: u8 = 2;
 const STRING_INDEX_SERIAL_NUMBER: u8 = 3;