From 0f463fe671455670efcf4a93e526b2a9082b0afe Mon Sep 17 00:00:00 2001
From: Daniel Drake <dsd@gentoo.org>
Date: Sat, 3 May 2008 16:24:11 +0100
Subject: [PATCH] Add libusb_set_configuration()

---
 libusb/core.c           | 25 +++++++++++++++++++++++++
 libusb/libusb.h         |  8 ++++++--
 libusb/libusbi.h        |  2 ++
 libusb/os/linux_usbfs.c | 17 +++++++++++++++++
 4 files changed, 50 insertions(+), 2 deletions(-)

diff --git a/libusb/core.c b/libusb/core.c
index d13f434..3924eb2 100644
--- a/libusb/core.c
+++ b/libusb/core.c
@@ -541,6 +541,31 @@ API_EXPORTED libusb_device *libusb_get_device(libusb_device_handle *dev_handle)
 }
 
 /** \ingroup dev
+ * Set the active configuration for a device. The operating system may have
+ * already set an active configuration on the device, but for portability
+ * reasons you should use this function to select the configuration you want
+ * before claiming any interfaces.
+ *
+ * If you wish to change to another configuration at some later time, you
+ * must release all claimed interfaces using libusb_release_interface() before
+ * setting a new active configuration.
+ *
+ * \param dev a device handle
+ * \param configuration the bConfigurationValue of the configuration you
+ * wish to activate
+ * \returns 0 on success
+ * \returns LIBUSB_ERROR_NOT_FOUND if the requested configuration does not exist
+ * \returns LIBUSB_ERROR_BUSY if interfaces are currently claimed
+ * \returns another LIBUSB_ERROR code on other failure
+ */
+API_EXPORTED int libusb_set_configuration(libusb_device_handle *dev,
+	int configuration)
+{
+	usbi_dbg("configuration %d", configuration);
+	return usbi_backend->set_configuration(dev, configuration);
+}
+
+/** \ingroup dev
  * Claim an interface on a given device handle. You must claim the interface
  * you wish to use before you can perform I/O on any of its endpoints.
  *
diff --git a/libusb/libusb.h b/libusb/libusb.h
index 44202c9..e1dcf3a 100644
--- a/libusb/libusb.h
+++ b/libusb/libusb.h
@@ -522,8 +522,9 @@ enum libusb_error {
 	LIBUSB_ERROR_INVALID_PARAM = -2,
 	LIBUSB_ERROR_ACCESS = -3,
 	LIBUSB_ERROR_NOT_FOUND = -4,
-	LIBUSB_ERROR_NO_MEM = -5,
-	LIBUSB_ERROR_OTHER = -6,
+	LIBUSB_ERROR_BUSY = -5,
+	LIBUSB_ERROR_NO_MEM = -6,
+	LIBUSB_ERROR_OTHER = -7,
 };
 
 /** \ingroup asyncio
@@ -648,12 +649,15 @@ uint8_t libusb_get_device_address(libusb_device *dev);
 libusb_device_handle *libusb_open(libusb_device *dev);
 void libusb_close(libusb_device_handle *dev_handle);
 libusb_device *libusb_get_device(libusb_device_handle *dev_handle);
+
+int libusb_set_configuration(libusb_device_handle *dev, int configuration);
 int libusb_claim_interface(libusb_device_handle *dev, int iface);
 int libusb_release_interface(libusb_device_handle *dev, int iface);
 
 libusb_device_handle *libusb_open_device_with_vid_pid(uint16_t vendor_id,
 	uint16_t product_id);
 
+
 int libusb_set_interface_altsetting(libusb_device_handle *dev, int iface,
 	int altsetting);
 
diff --git a/libusb/libusbi.h b/libusb/libusbi.h
index 69e565a..611f62b 100644
--- a/libusb/libusbi.h
+++ b/libusb/libusbi.h
@@ -273,6 +273,8 @@ struct usbi_os_backend {
 	int (*open)(struct libusb_device_handle *handle);
 	void (*close)(struct libusb_device_handle *handle);
 
+	int (*set_configuration)(struct libusb_device_handle *handle, int config);
+
 	int (*claim_interface)(struct libusb_device_handle *handle, int iface);
 	int (*release_interface)(struct libusb_device_handle *handle, int iface);
 
diff --git a/libusb/os/linux_usbfs.c b/libusb/os/linux_usbfs.c
index a2b792c..5849864 100644
--- a/libusb/os/linux_usbfs.c
+++ b/libusb/os/linux_usbfs.c
@@ -421,6 +421,22 @@ static void op_close(struct libusb_device_handle *dev_handle)
 	close(fd);
 }
 
+static int op_set_configuration(struct libusb_device_handle *handle, int config)
+{
+	int fd = __device_handle_priv(handle)->fd;
+	int r = ioctl(fd, IOCTL_USBFS_SETCONFIG, &config);
+	if (r) {
+		if (errno == EINVAL)
+			return LIBUSB_ERROR_NOT_FOUND;
+		else if (errno == EBUSY)
+			return LIBUSB_ERROR_BUSY;
+
+		usbi_err("failed, error %d errno %d", r, errno);
+		return LIBUSB_ERROR_OTHER;
+	}
+	return 0;
+}
+
 static int op_claim_interface(struct libusb_device_handle *handle, int iface)
 {
 	int fd = __device_handle_priv(handle)->fd;
@@ -1096,6 +1112,7 @@ const struct usbi_os_backend linux_usbfs_backend = {
 	.get_device_list = op_get_device_list,
 	.open = op_open,
 	.close = op_close,
+	.set_configuration = op_set_configuration,
 	.claim_interface = op_claim_interface,
 	.release_interface = op_release_interface,
 
-- 
2.7.4