From 89ddb292a2eb335585347f3713411f7775066c7b Mon Sep 17 00:00:00 2001
From: cepetr <petr@cerninovi.cz>
Date: Thu, 20 Mar 2025 15:29:14 +0100
Subject: [PATCH] feat(core): add event polling to usb vcp driver

[no changelog]
---
 core/embed/io/usb/stm32/usb_class_vcp.c | 58 +++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/core/embed/io/usb/stm32/usb_class_vcp.c b/core/embed/io/usb/stm32/usb_class_vcp.c
index 7e2be20ecd..1b732f2836 100644
--- a/core/embed/io/usb/stm32/usb_class_vcp.c
+++ b/core/embed/io/usb/stm32/usb_class_vcp.c
@@ -22,6 +22,7 @@
 #include <trezor_rtl.h>
 
 #include <io/usb_vcp.h>
+#include <sys/sysevent_source.h>
 
 #include "usb_internal.h"
 
@@ -162,6 +163,8 @@ _Static_assert(sizeof(usb_vcp_state_t) <= USBD_CLASS_STATE_MAX_SIZE);
 static const USBD_ClassTypeDef usb_vcp_class;
 static const USBD_ClassTypeDef usb_vcp_data_class;
 
+static const syshandle_vmt_t usb_vcp_handle_vmt;
+
 #define usb_get_vcp_state(iface_num) \
   ((usb_vcp_state_t *)usb_get_iface_state(iface_num, &usb_vcp_class))
 
@@ -449,12 +452,21 @@ static uint8_t usb_vcp_class_init(USBD_HandleTypeDef *dev, uint8_t cfg_idx) {
   USBD_LL_PrepareReceive(dev, state->ep_out, state->rx_packet,
                          state->max_packet_len);
 
+  uint8_t iface_num = state->desc_block->iface_data.bInterfaceNumber;
+  syshandle_t handle = SYSHANDLE_USB_IFACE_0 + iface_num;
+  syshandle_register(handle, &usb_vcp_handle_vmt, state);
+  // !@# TODO check result
+
   return USBD_OK;
 }
 
 static uint8_t usb_vcp_class_deinit(USBD_HandleTypeDef *dev, uint8_t cfg_idx) {
   usb_vcp_state_t *state = (usb_vcp_state_t *)dev->pUserData;
 
+  uint8_t iface_num = state->desc_block->iface_data.bInterfaceNumber;
+  syshandle_t handle = SYSHANDLE_USB_IFACE_0 + iface_num;
+  syshandle_unregister(handle);
+
   // Flush endpoints
   USBD_LL_FlushEP(dev, state->ep_in);
   USBD_LL_FlushEP(dev, state->ep_out);
@@ -590,4 +602,50 @@ static const USBD_ClassTypeDef usb_vcp_class = {
 
 static const USBD_ClassTypeDef usb_vcp_data_class = {};
 
+static void on_event_poll(void *context, bool read_awaited,
+                          bool write_awaited) {
+  usb_vcp_state_t *state = (usb_vcp_state_t *)context;
+
+  uint8_t iface_num = state->desc_block->iface_data.bInterfaceNumber;
+  syshandle_t handle = SYSHANDLE_USB_IFACE_0 + iface_num;
+
+  if (read_awaited && usb_vcp_can_read(iface_num)) {
+    syshandle_signal_read_ready(handle, NULL);
+  }
+
+  if (write_awaited && usb_vcp_can_write(iface_num)) {
+    syshandle_signal_write_ready(handle, NULL);
+  }
+}
+
+static bool on_check_read_ready(void *context, systask_id_t task_id,
+                                void *param) {
+  usb_vcp_state_t *state = (usb_vcp_state_t *)context;
+  uint8_t iface_num = state->desc_block->iface_data.bInterfaceNumber;
+
+  UNUSED(task_id);
+  UNUSED(param);
+
+  return usb_vcp_can_read(iface_num);
+}
+
+static bool on_check_write_ready(void *context, systask_id_t task_id,
+                                 void *param) {
+  usb_vcp_state_t *state = (usb_vcp_state_t *)context;
+  uint8_t iface_num = state->desc_block->iface_data.bInterfaceNumber;
+
+  UNUSED(task_id);
+  UNUSED(param);
+
+  return usb_vcp_can_write(iface_num);
+}
+
+static const syshandle_vmt_t usb_vcp_handle_vmt = {
+    .task_created = NULL,
+    .task_killed = NULL,
+    .check_read_ready = on_check_read_ready,
+    .check_write_ready = on_check_write_ready,
+    .poll = on_event_poll,
+};
+
 #endif  // KERNEL_MODE