diff --git a/core/embed/io/usb/inc/io/usb_vcp.h b/core/embed/io/usb/inc/io/usb_vcp.h
index 623d99f460..aeac05e9cb 100644
--- a/core/embed/io/usb/inc/io/usb_vcp.h
+++ b/core/embed/io/usb/inc/io/usb_vcp.h
@@ -50,8 +50,8 @@ typedef struct {
   uint8_t ep_out;  // Address of OUT endpoint
 #endif
   uint8_t polling_interval;  // In units of 1ms
-  uint8_t max_packet_len;  // Length of the biggest packet, and of tx_packet and
-                           // rx_packet
+  uint16_t max_packet_len;   // Length of the biggest packet, and of tx_packet
+                             // and rx_packet
 } usb_vcp_info_t;
 
 secbool __wur usb_vcp_add(const usb_vcp_info_t *vcp_info);
diff --git a/core/embed/io/usb/stm32/usb_class_vcp.c b/core/embed/io/usb/stm32/usb_class_vcp.c
index 288303fec2..ff3fc31b19 100644
--- a/core/embed/io/usb/stm32/usb_class_vcp.c
+++ b/core/embed/io/usb/stm32/usb_class_vcp.c
@@ -152,7 +152,7 @@ typedef struct {
   uint8_t ep_cmd;
   uint8_t ep_in;
   uint8_t ep_out;
-  uint8_t max_packet_len;
+  uint16_t max_packet_len;
   uint8_t ep_in_is_idle;  // Set to 1 after IN endpoint gets idle
   uint8_t cmd_buffer[USB_CDC_MAX_CMD_PACKET_LEN];
 } usb_vcp_state_t;
diff --git a/core/embed/projects/prodtest/main.c b/core/embed/projects/prodtest/main.c
index 8482274309..d4a75333ef 100644
--- a/core/embed/projects/prodtest/main.c
+++ b/core/embed/projects/prodtest/main.c
@@ -17,6 +17,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <trezor_bsp.h>
 #include <trezor_model.h>
 #include <trezor_rtl.h>
 
@@ -116,12 +117,17 @@ static size_t console_write(void *context, const char *buf, size_t size) {
 
 static void vcp_intr(void) { cli_abort(&g_cli); }
 
-static void usb_init_all(void) {
-  enum {
-    VCP_PACKET_LEN = 64,
-    VCP_BUFFER_LEN = 1024,
-  };
+#if defined(USE_USB_HS)
+#define VCP_PACKET_LEN 512
+#elif defined(USE_USB_FS)
+#define VCP_PACKET_LEN 64
+#else
+#error "USB type not defined"
+#endif
 
+#define VCP_BUFFER_LEN 1024
+
+static void usb_init_all(void) {
   static const usb_dev_info_t dev_info = {
       .device_class = 0xEF,     // Composite Device Class
       .device_subclass = 0x02,  // Common Class