shared/tinyusb: Add per-driver runtime USB class control.

This change allows USB class drivers (CDC, MSC, NCM) to be individually
enabled/disabled at runtime without requiring TinyUSB submodule changes.

Classes are always compiled in but only enabled drivers appear in USB
descriptors. When runtime device mode is disabled, all compiled classes
are auto-enabled for backward compatibility. When enabled, only CDC is
enabled by default.

Signed-off-by: Andrew Leech <[email protected]>

Author: pi-anl

extmod/machine_usb_device.c

@@ -229,6 +229,58 @@ static mp_obj_t usb_device_config(size_t n_args, const mp_obj_t *pos_args, mp_ma
 }
 static MP_DEFINE_CONST_FUN_OBJ_KW(usb_device_config_obj, 1, usb_device_config);
 
+// Per-class control methods
+static mp_obj_t usb_device_enable_cdc(size_t n_args, const mp_obj_t *args) {
+    mp_obj_usb_device_t *self = MP_OBJ_TO_PTR(args[0]);
+    
+    if (self->active) {
+        mp_raise_OSError(MP_EINVAL);
+    }
+    
+    if (n_args == 1) {
+        return mp_obj_new_bool(mp_usbd_class_state.cdc_enabled);
+    } else {
+        bool enable = mp_obj_is_true(args[1]);
+        mp_usbd_enable_class_cdc(enable);
+        return mp_const_none;
+    }
+}
+static MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(usb_device_enable_cdc_obj, 1, 2, usb_device_enable_cdc);
+
+static mp_obj_t usb_device_enable_msc(size_t n_args, const mp_obj_t *args) {
+    mp_obj_usb_device_t *self = MP_OBJ_TO_PTR(args[0]);
+    
+    if (self->active) {
+        mp_raise_OSError(MP_EINVAL);
+    }
+    
+    if (n_args == 1) {
+        return mp_obj_new_bool(mp_usbd_class_state.msc_enabled);
+    } else {
+        bool enable = mp_obj_is_true(args[1]);
+        mp_usbd_enable_class_msc(enable);
+        return mp_const_none;
+    }
+}
+static MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(usb_device_enable_msc_obj, 1, 2, usb_device_enable_msc);
+
+static mp_obj_t usb_device_enable_ncm(size_t n_args, const mp_obj_t *args) {
+    mp_obj_usb_device_t *self = MP_OBJ_TO_PTR(args[0]);
+    
+    if (self->active) {
+        mp_raise_OSError(MP_EINVAL);
+    }
+    
+    if (n_args == 1) {
+        return mp_obj_new_bool(mp_usbd_class_state.ncm_enabled);
+    } else {
+        bool enable = mp_obj_is_true(args[1]);
+        mp_usbd_enable_class_ncm(enable);
+        return mp_const_none;
+    }
+}
+static MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(usb_device_enable_ncm_obj, 1, 2, usb_device_enable_ncm);
+
 static const MP_DEFINE_BYTES_OBJ(builtin_default_desc_dev_obj,
     &mp_usbd_builtin_desc_dev, sizeof(tusb_desc_device_t));
 
@@ -278,6 +330,11 @@ static const mp_rom_map_elem_t usb_device_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR_active), MP_ROM_PTR(&usb_device_active_obj) },
     { MP_ROM_QSTR(MP_QSTR_stall), MP_ROM_PTR(&usb_device_stall_obj) },
     { MP_ROM_QSTR(MP_QSTR_remote_wakeup), MP_ROM_PTR(&usb_remote_wakeup_obj) },
+    
+    // Per-class control methods
+    { MP_ROM_QSTR(MP_QSTR_enable_cdc), MP_ROM_PTR(&usb_device_enable_cdc_obj) },
+    { MP_ROM_QSTR(MP_QSTR_enable_msc), MP_ROM_PTR(&usb_device_enable_msc_obj) },
+    { MP_ROM_QSTR(MP_QSTR_enable_ncm), MP_ROM_PTR(&usb_device_enable_ncm_obj) },
 
     // Built-in driver constants
     { MP_ROM_QSTR(MP_QSTR_BUILTIN_NONE), MP_ROM_PTR(&mp_type_usb_device_builtin_none) },

shared/tinyusb/mp_usbd.h

@@ -80,6 +80,35 @@ extern void mp_usbd_port_get_serial_number(char *buf);
 // length (2 * bytes_len + 1) (including NUL terminator).
 void mp_usbd_hex_str(char *out_str, const uint8_t *bytes, size_t bytes_len);
 
+// Per-class runtime enable/disable state
+typedef struct {
+    bool cdc_enabled;
+    bool msc_enabled;
+    bool ncm_enabled;
+} mp_usbd_class_state_t;
+
+// Global class enable state
+extern mp_usbd_class_state_t mp_usbd_class_state;
+
+// Functions to control USB classes via bitfield flags
+void mp_usbd_update_class_state(uint8_t flags);
+void mp_usbd_init_class_state(void);
+
+// Initialise TinyUSB device.
+static inline void mp_usbd_init_tud(void) {
+    // Initialize class state before TinyUSB init
+    mp_usbd_init_class_state();
+
+    tusb_init();
+    #if MICROPY_HW_USB_CDC
+    tud_cdc_configure_fifo_t cfg = { .rx_persistent = 0, .tx_persistent = 1 };
+    tud_cdc_configure_fifo(&cfg);
+    #endif
+}
+
+// Get dynamic descriptor length based on enabled classes
+size_t mp_usbd_get_descriptor_cfg_len(void);
+
 // Length of built-in configuration descriptor
 #define MP_USBD_BUILTIN_DESC_CFG_LEN ( \
     (CFG_TUD_CDC ? (TUD_CDC_DESC_LEN) : 0) + \
@@ -102,6 +131,7 @@ const char *mp_usbd_runtime_string_cb(uint8_t index);
 // Maximum number of pending exceptions per single TinyUSB task execution
 #define MP_USBD_MAX_PEND_EXCS 2
 
+// Full runtime USB device structure
 typedef struct {
     mp_obj_base_t base;
 
@@ -136,6 +166,23 @@ typedef struct {
     mp_obj_t pend_excs[MP_USBD_MAX_PEND_EXCS];
 } mp_obj_usb_device_t;
 
+#else // Static USBD drivers only
+
+// Minimal USB device structure for static mode (builtin_driver control only)
+typedef struct {
+    mp_obj_base_t base;
+    mp_obj_t builtin_driver; // Points to one of mp_type_usb_device_builtin_nnn
+    bool active; // Has the user set the USB device active?
+} mp_obj_usb_device_t;
+
+static inline void mp_usbd_init(void) {
+    // Without runtime USB support, this can be a thin wrapper wrapper around tusb_init()
+    // which is called in the below helper function.
+    mp_usbd_init_tud();
+}
+
+#endif
+
 // Built-in constant objects, possible values of builtin_driver
 //
 // (Currently not possible to change built-in drivers at runtime, just enable/disable.)
@@ -147,16 +194,6 @@ static inline bool mp_usb_device_builtin_enabled(const mp_obj_usb_device_t *usbd
     return usbd->builtin_driver != MP_OBJ_FROM_PTR(&mp_type_usb_device_builtin_none);
 }
 
-#else // Static USBD drivers only
-
-static inline void mp_usbd_init(void) {
-    // Without runtime USB support, this can be a thin wrapper wrapper around tusb_init()
-    // which is called in the below helper function.
-    mp_usbd_init_tud();
-}
-
-#endif
-
 #endif // MICROPY_HW_ENABLE_USBDEV
 
 #endif // MICROPY_INCLUDED_SHARED_TINYUSB_USBD_H