# HG changeset patch
# User Mychaela Falconia <falcon@freecalypso.org>
# Date 1694399231 0
# Node ID 5160f67179039df2a233b6c67f3acfe35392d978
# Parent  dbaf239436cf4106b36fa0378bf0c6ab313e344c
libuwrap: implement function to claim/unbind all interfaces

diff -r dbaf239436cf -r 5160f6717903 libuwrap/claim_if.c
--- a/libuwrap/claim_if.c	Mon Sep 11 01:06:03 2023 +0000
+++ b/libuwrap/claim_if.c	Mon Sep 11 02:27:11 2023 +0000
@@ -1,10 +1,15 @@
 /*
- * When we are reprogramming the EEPROM on DUART28 or possibly other devices
- * in the future where we know that we are operating on a multichannel FTDI
- * chip (or perhaps a multichannel chip from some other vendor), it is most
- * philosophically correct to bump off ftdi_sio from both interfaces,
- * removing both ttyUSB devices.  Here we implement a function for claiming
- * one interface, easily callable for multiple interfaces in a row.
+ * The operation of programming an FTDI EEPROM *can* be done without ever
+ * claiming any of the chip's interfaces and without unbinding ttyUSB from
+ * any channel, even if we are doing the special magic sequence for FT232R.
+ * However, given the identity-altering nature of EEPROM programming it is
+ * generally a good idea to claim all interfaces and unbind all ttyUSB
+ * devices, and in the case of FT232R the magic sequence breaks normal
+ * UART operation.
+ *
+ * This library module provides building block functions: a function for
+ * claiming one interface and a higher-level function claiming all interfaces
+ * of a multichannel device.
  */
 
 #include <stdio.h>
@@ -21,3 +26,11 @@
 		exit(1);
 	}
 }
+
+void usbwrap_claim_all_ifs(usb_dev_handle *usbh, unsigned nchannels)
+{
+	unsigned n;
+
+	for (n = 0; n < nchannels; n++)
+		usbwrap_claim_interface(usbh, n, 1);
+}
diff -r dbaf239436cf -r 5160f6717903 libuwrap/open_close.h
--- a/libuwrap/open_close.h	Mon Sep 11 01:06:03 2023 +0000
+++ b/libuwrap/open_close.h	Mon Sep 11 02:27:11 2023 +0000
@@ -3,3 +3,4 @@
 
 extern void
 usbwrap_claim_interface(usb_dev_handle *usbh, int ifnum, int detach);
+extern void usbwrap_claim_all_ifs(usb_dev_handle *usbh, unsigned nchannels);