Independent HID OUT buffer

- Separate buffer for FEATURE and OUT reports
- Prevents a bug where an OUT report can overwrite a FEATURE report and vice versa

src/class/hid/hid_device.c

@@ -52,6 +52,7 @@ typedef struct
 
   CFG_TUSB_MEM_ALIGN uint8_t epin_buf[CFG_TUD_HID_EP_BUFSIZE];
   CFG_TUSB_MEM_ALIGN uint8_t epout_buf[CFG_TUD_HID_EP_BUFSIZE];
+  CFG_TUSB_MEM_ALIGN uint8_t feat_buf[CFG_TUD_HID_FEATURE_BUFSIZE];
 
   // TODO save hid descriptor since host can specifically request this after enumeration
   // Note: HID descriptor may be not available from application after enumeration
@@ -320,16 +321,32 @@ bool hidd_control_xfer_cb (uint8_t rhport, uint8_t stage, tusb_control_request_t
       case  HID_REQ_CONTROL_SET_REPORT:
         if ( stage == CONTROL_STAGE_SETUP )
         {
-          TU_VERIFY(request->wLength <= sizeof(p_hid->epout_buf));
-          tud_control_xfer(rhport, request, p_hid->epout_buf, request->wLength);
+          uint8_t const report_type = tu_u16_high(request->wValue);
+          uint8_t * report_buf;
+
+          if ( report_type == HID_REPORT_TYPE_FEATURE )
+          {
+            TU_VERIFY(request->wLength <= sizeof(p_hid->feat_buf));
+
+            report_buf = p_hid->feat_buf;
+          }
+          else
+          {
+            TU_VERIFY(request->wLength <= sizeof(p_hid->epout_buf));
+
+            report_buf = p_hid->epout_buf;
+          }
+
+          tud_control_xfer(rhport, request, report_buf, request->wLength);
         }
         else if ( stage == CONTROL_STAGE_ACK )
         {
           uint8_t const report_type = tu_u16_high(request->wValue);
           uint8_t const report_id   = tu_u16_low(request->wValue);
 
-          uint8_t const* report_buf = p_hid->epout_buf;
-          uint16_t report_len = tu_min16(request->wLength, CFG_TUD_HID_EP_BUFSIZE);
+          uint8_t const* report_buf = (report_type == HID_REPORT_TYPE_FEATURE) ? p_hid->feat_buf : p_hid->epout_buf;
+
+          uint16_t report_len = tu_min16(request->wLength, (report_type == HID_REPORT_TYPE_FEATURE) ? CFG_TUD_HID_FEATURE_BUFSIZE : CFG_TUD_HID_EP_BUFSIZE);
 
           // If host request a specific Report ID, extract report ID in buffer before invoking callback
           if ( (report_id != HID_REPORT_TYPE_INVALID) && (report_len > 1) && (report_id == report_buf[0]) )