Improve JVS bus life cycle handling

divahook/dllmain.c

@@ -45,12 +45,7 @@ static DWORD CALLBACK diva_pre_startup(void)
             "AAV0",
             diva_hook_mod);
 
-    amex_hook_init(&diva_hook_cfg.amex);
-
-    if (diva_hook_cfg.amex.jvs.enable) {
-        diva_jvs_init();
-    }
-
+    amex_hook_init(&diva_hook_cfg.amex, diva_jvs_init);
     sg_reader_hook_init(&diva_hook_cfg.aime, 10);
     slider_hook_init();
 

divahook/jvs.c

@@ -28,10 +28,25 @@ static const struct io3_ops diva_jvs_io3_ops = {
 
 static struct io3 diva_jvs_io3;
 
-void diva_jvs_init(void)
+HRESULT diva_jvs_init(struct jvs_node **out)
 {
+    HRESULT hr;
+
+    assert(out != NULL);
+
+    dprintf("JVS I/O: Starting Diva backend DLL\n");
+    hr = diva_io_jvs_init();
+
+    if (FAILED(hr)) {
+        dprintf("JVS I/O: Backend error, I/O disconnected: %x\n", (int) hr);
+
+        return hr;
+    }
+
     io3_init(&diva_jvs_io3, NULL, &diva_jvs_io3_ops, NULL);
-    jvs_attach(&diva_jvs_io3.jvs);
+    *out = io3_to_jvs_node(&diva_jvs_io3);
+
+    return S_OK;
 }
 
 static void diva_jvs_read_switches(void *ctx, struct io3_switch_state *out)

divahook/jvs.h

@@ -1,3 +1,7 @@
 #pragma once
 
-void diva_jvs_init(void);
+#include <windows.h>
+
+#include "jvs/jvs-bus.h"
+
+HRESULT diva_jvs_init(struct jvs_node **root);

divahook/slider.c

@@ -73,6 +73,17 @@ static HRESULT slider_handle_irp_locked(struct irp *irp)
     struct iobuf req_iobuf;
     HRESULT hr;
 
+    if (irp->op == IRP_OP_OPEN) {
+        dprintf("Diva slider: Starting backend DLL\n");
+        hr = diva_io_jvs_init();
+
+        if (FAILED(hr)) {
+            dprintf("Diva slider: Backend DLL error: %x\n", (int) hr);
+
+            return hr;
+        }
+    }
+
     hr = uart_handle_irp(&slider_uart, irp);
 
     if (FAILED(hr) || irp->op != IRP_OP_WRITE) {