drivers/libusb{0,1}.c: reset driver parameters while enumerating

NEWS.adoc

@@ -149,6 +149,11 @@ https://github.com/networkupstools/nut/milestone/11
      by default: `powercom_sdcmd_byte_order_fallback`. [PR #2480]
    * `cps-hid` subdriver now supports more variables, as available on e.g.
      CP1350EPFCLCD model. [PR #2540]
+   * USB parameters (per `usb_communication_subdriver_t`) are now set back to
+     their default values during enumeration after probing each subdriver.
+     Having an unrelated device connected with a VID:PID matching the
+     `arduino-hid` subdriver prevented use of an actual `usb-hid` device due to
+     changes made to this struct during probe. [#2611]
 
  - bicker_ser: added new driver for Bicker 12/24Vdc UPS via RS-232 serial
    communication protocol, which supports any UPS shipped with the PSZ-1053
@@ -170,6 +175,10 @@ https://github.com/networkupstools/nut/milestone/11
      `nutdrv_atcl_usb`) and for general code to collect string readings and
      other data points, and for `nut-scanner`.
 
+ - USB drivers should now be more likely to succeed with iterative detection
+   of an UPS interface on a composite USB device or when looking at devices
+   with non-default interface/endpoint/config numbers. [PR #2611]
+
  - Introduced a new driver concept for interaction with OS-reported hardware
    monitoring readings. Currently instantiated as `hwmon_ina219` specifically
    made for Texas Instruments INA219 chip as exposed in the Linux "hwmon"

docs/nut.dict

@@ -1,4 +1,4 @@
-personal_ws-1.1 en 3214 utf-8
+personal_ws-1.1 en 3215 utf-8
 AAC
 AAS
 ABI

drivers/libusb0.c

@@ -186,6 +186,20 @@ static int nut_libusb_set_altinterface(usb_dev_handle *udev)
 	return ret;
 }
 
+static void nut_libusb_subdriver_defaults(usb_communication_subdriver_t *subdriver)
+{
+	if (!getval("usb_config_index"))
+		subdriver->usb_config_index = LIBUSB_DEFAULT_CONF_INDEX;
+	if (!getval("usb_hid_rep_index"))
+		subdriver->hid_rep_index = LIBUSB_DEFAULT_INTERFACE;
+	if (!getval("usb_hid_desc_index"))
+		subdriver->hid_desc_index = LIBUSB_DEFAULT_DESC_INDEX;
+	if (!getval("usb_hid_ep_in"))
+		subdriver->hid_ep_in = LIBUSB_DEFAULT_HID_EP_IN;
+	if (!getval("usb_hid_ep_out"))
+		subdriver->hid_ep_out = LIBUSB_DEFAULT_HID_EP_OUT;
+}
+
 #define usb_control_msg         typesafe_control_msg
 
 /* On success, fill in the curDevice structure and return the report
@@ -711,6 +725,8 @@ static int nut_libusb_open(usb_dev_handle **udevp,
 			/* if (if_claimed)
 				usb_release_interface(udev, 0); */
 			usb_close(udev);
+			/* reset any parameters modified by unmatched drivers back to defaults */
+			nut_libusb_subdriver_defaults(&usb_subdriver);
 		}
 	}
 

drivers/libusb1.c

@@ -152,6 +152,20 @@ static int nut_libusb_set_altinterface(libusb_device_handle *udev)
 	return ret;
 }
 
+static void nut_libusb_subdriver_defaults(usb_communication_subdriver_t *subdriver)
+{
+	if (!getval("usb_config_index"))
+		subdriver->usb_config_index = LIBUSB_DEFAULT_CONF_INDEX;
+	if (!getval("usb_hid_rep_index"))
+		subdriver->hid_rep_index = LIBUSB_DEFAULT_INTERFACE;
+	if (!getval("usb_hid_desc_index"))
+		subdriver->hid_desc_index = LIBUSB_DEFAULT_DESC_INDEX;
+	if (!getval("usb_hid_ep_in"))
+		subdriver->hid_ep_in = LIBUSB_DEFAULT_HID_EP_IN;
+	if (!getval("usb_hid_ep_out"))
+		subdriver->hid_ep_out = LIBUSB_DEFAULT_HID_EP_OUT;
+}
+
 /* On success, fill in the curDevice structure and return the report
  * descriptor length. On failure, return -1.
  * Note: When callback is not NULL, the report descriptor will be
@@ -795,6 +809,8 @@ static int nut_libusb_open(libusb_device_handle **udevp,
 			/* if (if_claimed)
 				libusb_release_interface(udev, usb_subdriver.hid_rep_index); */
 			libusb_close(udev);
+			/* reset any parameters modified by unmatched drivers back to defaults */
+			nut_libusb_subdriver_defaults(&usb_subdriver);
 	}
 
 	*udevp = NULL;