deprecated `usbd_control.c` and merge its functionality into `usbd.c`

1 files changed, 165 insertions, 8 deletions

diff --git a/src/device/usbd.c b/src/device/usbd.c
index da0ffb4c6..acf808bf6 100644
--- a/src/device/usbd.c
+++ b/src/device/usbd.c
@@ -419,11 +419,10 @@ static bool process_test_mode_cb(uint8_t rhport, uint8_t stage, tusb_control_req
 }
 #endif
 
-// from usbd_control.c
-void usbd_control_reset(void);
-void usbd_control_set_request(tusb_control_request_t const *request);
-void usbd_control_set_complete_callback( usbd_control_xfer_cb_t fp );
-bool usbd_control_xfer_cb (uint8_t rhport, uint8_t ep_addr, xfer_result_t event, uint32_t xferred_bytes);
+// Control Endpoint
+static void usbd_control_reset(void);
+static void usbd_control_set_complete_callback(usbd_control_xfer_cb_t fp);
+static bool usbd_control_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint32_t xferred_bytes);
 
 //--------------------------------------------------------------------+
 // Weak stubs: invoked if no strong implementation is available
@@ -809,6 +808,157 @@ void tud_task_ext(uint32_t timeout_ms, bool in_isr) {
 }
 
 //--------------------------------------------------------------------+
+// Control Endpoint
+//--------------------------------------------------------------------+
+
+// Weak hook: invoked when the control transfer's status stage completes
+TU_ATTR_WEAK void dcd_edpt0_status_complete(uint8_t rhport, const tusb_control_request_t* request) {
+  (void) rhport;
+  (void) request;
+}
+
+typedef struct {
+  tusb_control_request_t request;
+  uint8_t* buffer;
+  uint16_t data_len;
+  uint16_t total_xferred;
+  usbd_control_xfer_cb_t complete_cb;
+} usbd_control_xfer_t;
+
+static usbd_control_xfer_t _ctrl_xfer;
+
+CFG_TUD_MEM_SECTION static struct {
+  TUD_EPBUF_DEF(buf, CFG_TUD_ENDPOINT0_BUFSIZE);
+} _ctrl_epbuf;
+
+uint8_t* usbd_get_ctrl_buf(void) {
+  return _ctrl_epbuf.buf;
+}
+
+// Endpoint used for the Status stage of a control transfer.
+// Per USB 2.0 §9.3.1, when wLength == 0 the Direction bit is ignored and the Status
+// stage is always IN. Otherwise the Status stage is opposite of the Data stage direction.
+TU_ATTR_ALWAYS_INLINE static inline uint8_t status_stage_ep(const tusb_control_request_t* request) {
+  return (request->wLength != 0 && request->bmRequestType_bit.direction) ? TU_EP0_OUT : TU_EP0_IN;
+}
+
+// Queue ZLP status transaction
+TU_ATTR_ALWAYS_INLINE static inline bool status_stage_xact(uint8_t rhport, uint8_t ep_status) {
+  return usbd_edpt_xfer(rhport, ep_status, NULL, 0, false);
+}
+
+// Queue a transaction in Data Stage. Each transaction has up to Endpoint0's max
+// packet size. This function can also transfer a zero-length packet.
+static bool data_stage_xact(uint8_t rhport) {
+  const uint16_t xact_len = tu_min16(_ctrl_xfer.data_len - _ctrl_xfer.total_xferred, CFG_TUD_ENDPOINT0_BUFSIZE);
+  uint8_t ep_addr = TU_EP0_OUT;
+
+  if (_ctrl_xfer.request.bmRequestType_bit.direction == TUSB_DIR_IN) {
+    ep_addr = TU_EP0_IN;
+    if (0u != xact_len && _ctrl_xfer.buffer != _ctrl_epbuf.buf) {
+      TU_VERIFY(0 == tu_memcpy_s(_ctrl_epbuf.buf, CFG_TUD_ENDPOINT0_BUFSIZE, _ctrl_xfer.buffer, xact_len));
+    }
+  }
+
+  return usbd_edpt_xfer(rhport, ep_addr, xact_len ? _ctrl_epbuf.buf : NULL, xact_len, false);
+}
+
+// Status phase
+bool tud_control_status(uint8_t rhport, const tusb_control_request_t* request) {
+  // _ctrl_xfer fields are pre-initialized at process_control_request entry
+  (void) request;
+  return status_stage_xact(rhport, status_stage_ep(&_ctrl_xfer.request));
+}
+
+// Transmit data to/from the control endpoint. If wLength is zero, a status packet is sent instead.
+bool tud_control_xfer(uint8_t rhport, const tusb_control_request_t* request, void* buffer, uint16_t len) {
+  // _ctrl_xfer.request and reset fields are pre-initialized at process_control_request entry
+  (void) request;
+  _ctrl_xfer.buffer = (uint8_t*) buffer;
+  _ctrl_xfer.data_len = tu_min16(len, _ctrl_xfer.request.wLength);
+
+  if (_ctrl_xfer.request.wLength > 0U) {
+    if (_ctrl_xfer.data_len > 0U) {
+      TU_ASSERT(buffer);
+    }
+    TU_ASSERT(data_stage_xact(rhport));
+  } else {
+    // wLength == 0: Status stage is always IN per USB 2.0 §9.3.1
+    TU_ASSERT(status_stage_xact(rhport, TU_EP0_IN));
+  }
+
+  return true;
+}
+
+static void usbd_control_reset(void) {
+  tu_varclr(&_ctrl_xfer);
+}
+
+static void usbd_control_set_complete_callback(usbd_control_xfer_cb_t fp) {
+  _ctrl_xfer.complete_cb = fp;
+}
+
+// Callback when a transaction completes on the DATA stage or Status stage of EP0
+static bool usbd_control_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint32_t xferred_bytes) {
+  (void) result;
+
+  // Status Stage complete: ep_addr matches the resolved Status stage endpoint
+  uint8_t const ep_status = status_stage_ep(&_ctrl_xfer.request);
+  if (ep_addr == ep_status) {
+    TU_ASSERT(0 == xferred_bytes);
+
+    // invoke optional dcd hook if available
+    dcd_edpt0_status_complete(rhport, &_ctrl_xfer.request);
+
+    if (NULL != _ctrl_xfer.complete_cb) {
+      // TODO refactor with usbd_driver_print_control_complete_name
+      _ctrl_xfer.complete_cb(rhport, CONTROL_STAGE_ACK, &_ctrl_xfer.request);
+    }
+
+    return true;
+  }
+
+  // Data stage progress
+  if (_ctrl_xfer.request.bmRequestType_bit.direction == TUSB_DIR_OUT) {
+    TU_VERIFY(_ctrl_xfer.buffer);
+    if (_ctrl_xfer.buffer != _ctrl_epbuf.buf) {
+      memcpy(_ctrl_xfer.buffer, _ctrl_epbuf.buf, xferred_bytes);
+    }
+    TU_LOG_MEM(CFG_TUD_LOG_LEVEL, _ctrl_xfer.buffer, xferred_bytes, 2);
+  }
+
+  _ctrl_xfer.total_xferred += (uint16_t) xferred_bytes;
+  _ctrl_xfer.buffer += xferred_bytes;
+
+  // Data Stage complete when wLength reached or short packet (incl. ZLP) seen
+  if ((_ctrl_xfer.request.wLength == _ctrl_xfer.total_xferred) ||
+      (xferred_bytes < CFG_TUD_ENDPOINT0_BUFSIZE)) {
+    bool is_ok = true;
+
+    if (NULL != _ctrl_xfer.complete_cb) {
+      #if CFG_TUSB_DEBUG >= CFG_TUD_LOG_LEVEL
+      usbd_driver_print_control_complete_name(_ctrl_xfer.complete_cb);
+      #endif
+      // Callback can still stall control in status phase, e.g. OUT data doesn't make sense
+      is_ok = _ctrl_xfer.complete_cb(rhport, CONTROL_STAGE_DATA, &_ctrl_xfer.request);
+    }
+
+    if (is_ok) {
+      TU_ASSERT(status_stage_xact(rhport, ep_status));
+    } else {
+      // Stall both IN and OUT control endpoint
+      dcd_edpt_stall(rhport, TU_EP0_OUT);
+      dcd_edpt_stall(rhport, TU_EP0_IN);
+    }
+  } else {
+    // More data to transfer
+    TU_ASSERT(data_stage_xact(rhport));
+  }
+
+  return true;
+}
+
+//--------------------------------------------------------------------+
 // Control Request Parser & Handling
 //--------------------------------------------------------------------+
 
@@ -822,7 +972,14 @@ static bool invoke_class_control(uint8_t rhport, usbd_class_driver_t const * dri
 // This handles the actual request and its response.
 // Returns false if unable to complete the request, causing caller to stall control endpoints.
 static bool process_control_request(uint8_t rhport, tusb_control_request_t const * p_request) {
-  usbd_control_set_complete_callback(NULL);
+  // Initialize control transfer state for this request. The request copy must be
+  // visible to usbd_control_xfer_cb when the (asynchronous) status ZLP completes,
+  // since the SETUP packet event has already gone out of scope by then.
+  _ctrl_xfer.request = *p_request;
+  _ctrl_xfer.buffer = NULL;
+  _ctrl_xfer.total_xferred = 0;
+  _ctrl_xfer.data_len = 0;
+  _ctrl_xfer.complete_cb = NULL;
   TU_ASSERT(p_request->bmRequestType_bit.type < TUSB_REQ_TYPE_INVALID);
 
   // Vendor request
@@ -865,9 +1022,9 @@ static bool process_control_request(uint8_t rhport, tusb_control_request_t const
           // Depending on mcu, status phase could be sent either before or after changing device address,
           // or even require stack to not response with status at all
           // Therefore DCD must take full responsibility to response and include zlp status packet if needed.
-          usbd_control_set_request(p_request); // set request since DCD has no access to tud_control_status() API
+          // _ctrl_xfer.request was already populated at process_control_request() entry, so the
+          // status ZLP that the DCD queues will be recognized by usbd_control_xfer_cb().
           dcd_set_address(rhport, (uint8_t) p_request->wValue);
-          // skip tud_control_status()
           _usbd_dev.addressed = 1;
         break;