Add a libusb_get_device_speed function

Reworked version of my earlier patch, largely modelled (if not copy and pasted)
after / from Trygve Laugstøl's <trygvis@inamo.no> similar patch.

Note this patch does not add any OS specific code, I've a Linux version
in a separate patch.

Signed-off-By: Hans de Goede <hdegoede@redhat.com>

3 files changed, 34 insertions, 0 deletions

diff --git a/libusb/core.c b/libusb/core.c
index 2a0d5b0..a8aa87d 100644
--- a/libusb/core.c
+++ b/libusb/core.c
@@ -523,6 +523,7 @@ struct libusb_device *usbi_alloc_device(struct libusb_context *ctx,
 	dev->ctx = ctx;
 	dev->refcnt = 1;
 	dev->session_data = session_id;
+	dev->speed = LIBUSB_SPEED_UNKNOWN;
 	memset(&dev->os_priv, 0, priv_size);
 
 	usbi_mutex_lock(&ctx->usb_devs_lock);
@@ -680,6 +681,17 @@ uint8_t API_EXPORTED libusb_get_device_address(libusb_device *dev)
 	return dev->device_address;
 }
 
+/** \ingroup dev
+ * Get the negotiated speed of the device.
+ * \param dev a device
+ * \returns the device speed or LIBUSB_SPEED_UNKNOWN if the OS doesn't know or
+ * support returning the negotiated speed.
+ */
+enum libusb_speed API_EXPORTED libusb_get_device_speed(libusb_device *dev)
+{
+	return dev->speed;
+}
+
 static const struct libusb_endpoint_descriptor *find_endpoint(
 	struct libusb_config_descriptor *config, unsigned char endpoint)
 {
diff --git a/libusb/libusb.h b/libusb/libusb.h
index 45e20ec..3ea2c99 100644
--- a/libusb/libusb.h
+++ b/libusb/libusb.h
@@ -684,6 +684,26 @@ typedef struct libusb_device libusb_device;
  */
 typedef struct libusb_device_handle libusb_device_handle;
 
+/** \ingroup dev
+ * Speed codes. Indicates the speed at which the device is operating.
+ */
+enum libusb_speed {
+    /** The OS doesn't report or know the device speed. */
+    LIBUSB_SPEED_UNKNOWN = 0,
+
+    /** The device is operating at low speed (1.5MBit/s). */
+    LIBUSB_SPEED_LOW = 1,
+
+    /** The device is operating at full speed (12MBit/s). */
+    LIBUSB_SPEED_FULL = 2,
+
+    /** The device is operating at high speed (480MBit/s). */
+    LIBUSB_SPEED_HIGH = 3,
+
+    /** The device is operating at super speed (5000MBit/s). */
+    LIBUSB_SPEED_SUPER = 4,
+};
+
 /** \ingroup misc
  * Error codes. Most libusb functions return 0 on success or one of these
  * codes on failure.
@@ -890,6 +910,7 @@ void LIBUSB_CALL libusb_free_config_descriptor(
 	struct libusb_config_descriptor *config);
 uint8_t LIBUSB_CALL libusb_get_bus_number(libusb_device *dev);
 uint8_t LIBUSB_CALL libusb_get_device_address(libusb_device *dev);
+enum libusb_speed LIBUSB_CALL libusb_get_device_speed(libusb_device *dev);
 int LIBUSB_CALL libusb_get_max_packet_size(libusb_device *dev,
 	unsigned char endpoint);
 int LIBUSB_CALL libusb_get_max_iso_packet_size(libusb_device *dev,
diff --git a/libusb/libusbi.h b/libusb/libusbi.h
index 1ea7f26..564ee3e 100644
--- a/libusb/libusbi.h
+++ b/libusb/libusbi.h
@@ -276,6 +276,7 @@ struct libusb_device {
 	uint8_t bus_number;
 	uint8_t device_address;
 	uint8_t num_configurations;
+	enum libusb_speed speed;
 
 	struct list_head list;
 	unsigned long session_data;