io/util/usb: Add interrupt_transfer function

set_configuration was moved after the kernel_driver_active
check otherwise lxio device will fail to set config.

src/main/io/util/usb.c

@@ -99,20 +99,6 @@ void *io_usb_open(uint16_t vid, uint16_t pid, uint16_t config, uint16_t iface)
     return NULL;
   }
 
-  ret = libusb_set_configuration(dev, config);
-
-  if (ret != LIBUSB_SUCCESS) {
-    libusb_close(dev);
-    libusb_exit(ctx);
-
-    log_error(
-        "(%04X:%04X) Setting configuration failed",
-        vid,
-        pid,
-        libusb_error_name(ret));
-    return NULL;
-  }
-
   /* check if the device is attached to the kernel, detach it first then */
   if (libusb_kernel_driver_active(dev, iface) == 1) {
     ret = libusb_detach_kernel_driver(dev, iface);
@@ -130,6 +116,20 @@ void *io_usb_open(uint16_t vid, uint16_t pid, uint16_t config, uint16_t iface)
     }
   }
 
+  ret = libusb_set_configuration(dev, config);
+
+  if (ret != LIBUSB_SUCCESS) {
+    libusb_close(dev);
+    libusb_exit(ctx);
+
+    log_error(
+        "(%04X:%04X) Setting configuration failed",
+        vid,
+        pid,
+        libusb_error_name(ret));
+    return NULL;
+  }
+
   ret = libusb_claim_interface(dev, iface);
 
   if (ret != LIBUSB_SUCCESS) {
@@ -181,6 +181,31 @@ int32_t io_usb_control_transfer(
   return ret;
 }
 
+int32_t io_usb_interrupt_transfer(
+    void *handle,
+    int ep,
+    uint8_t *data,
+    uint16_t len,
+    uint32_t timeout)
+{
+  struct usb_io_ctx *dev = (struct usb_io_ctx *) handle;
+  int32_t ret, transferred;
+
+  ret =
+      libusb_interrupt_transfer(
+        dev->dev, ep, data, len, &transferred, timeout);
+
+  if (transferred != len) {
+    log_error(
+        "Interrupt transfer, addr %02x, handle %p failed: %s",
+        handle,
+        ep,
+        libusb_error_name(ret));
+  }
+
+  return transferred;
+}
+
 void io_usb_close(void *handle)
 {
   struct usb_io_ctx *dev = (struct usb_io_ctx *) handle;

src/main/io/util/usb_.h

@@ -42,6 +42,23 @@ int32_t io_usb_control_transfer(
     uint16_t len,
     uint32_t timeout);
 
+/**
+ * Execute an interrupt transfer request.
+ *
+ * @param handle Handle of an opened usb device
+ * @param ep Endpoint address to communicate with.
+ * @param data Pointer to an allocated buffer (depending on the vendor
+ *             specific request type, this can be a read or write buffer)
+ * @param len Length of the data to write/read
+ * @param timeout Timeout for the operation in ms
+ * @return Number of bytes read/written or -1 on error
+ */
+int32_t io_usb_interrupt_transfer(
+    void *handle, 
+    int ep, 
+    uint8_t *data,
+    uint16_t len, 
+    uint32_t timeout);
 /**
  * Close a opened usb device
  *