Add API for allocating / freeing usb3 bulk streams + Linux implementation

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

10 files changed, 149 insertions, 1 deletions

diff --git a/libusb/core.c b/libusb/core.c
index af92854..f766e62 100644
--- a/libusb/core.c
+++ b/libusb/core.c
@@ -1615,6 +1615,68 @@ int API_EXPORTED libusb_reset_device(libusb_device_handle *dev)
 	return usbi_backend->reset_device(dev);
 }
 
+/** \ingroup asyncio
+ * Allocate up to num_streams usb bulk streams on the specified endpoints. This
+ * function takes an array of endpoints rather then a single endpoint because
+ * some protocols require that endpoints are setup with similar stream ids.
+ * All endpoints passed in must belong to the same interface.
+ *
+ * Note this function may return less streams then requested.
+ *
+ * Stream id 0 is reserved, and should not be used to communicate with devices.
+ * If libusb_alloc_streams() returns with a value of N, you may use stream ids
+ * 1 to N.
+ *
+ * Since version 1.0.19, \ref LIBUSB_API_VERSION >= 0x01000103
+ *
+ * \param dev a device handle
+ * \param num_streams number of streams to try to allocate
+ * \param endpoints array of endpoints to allocate streams on
+ * \param num_endpoints length of the endpoints array
+ * \returns number of streams allocated, or a LIBUSB_ERROR code on failure
+ */
+int API_EXPORTED libusb_alloc_streams(libusb_device_handle *dev,
+	uint32_t num_streams, unsigned char *endpoints, int num_endpoints)
+{
+	usbi_dbg("streams %u eps %d", (unsigned) num_streams, num_endpoints);
+
+	if (!dev->dev->attached)
+		return LIBUSB_ERROR_NO_DEVICE;
+
+	if (usbi_backend->alloc_streams)
+		return usbi_backend->alloc_streams(dev, num_streams, endpoints,
+						   num_endpoints);
+	else
+		return LIBUSB_ERROR_NOT_SUPPORTED;
+}
+
+/** \ingroup asyncio
+ * Free usb bulk streams allocated with libusb_alloc_streams().
+ *
+ * Note streams are automatically free-ed when releasing an interface.
+ *
+ * Since version 1.0.19, \ref LIBUSB_API_VERSION >= 0x01000103
+ *
+ * \param dev a device handle
+ * \param endpoints array of endpoints to allocate streams on
+ * \param num_endpoints length of the endpoints array
+ * \returns LIBUSB_SUCCESS, or a LIBUSB_ERROR code on failure
+ */
+int API_EXPORTED libusb_free_streams(libusb_device_handle *dev,
+	unsigned char *endpoints, int num_endpoints)
+{
+	usbi_dbg("eps %d", num_endpoints);
+
+	if (!dev->dev->attached)
+		return LIBUSB_ERROR_NO_DEVICE;
+
+	if (usbi_backend->free_streams)
+		return usbi_backend->free_streams(dev, endpoints,
+						  num_endpoints);
+	else
+		return LIBUSB_ERROR_NOT_SUPPORTED;
+}
+
 /** \ingroup dev
  * Determine if a kernel driver is active on an interface. If a kernel driver
  * is active, you cannot claim the interface, and libusb will be unable to
diff --git a/libusb/libusb.h b/libusb/libusb.h
index 409b510..ccbad44 100644
--- a/libusb/libusb.h
+++ b/libusb/libusb.h
@@ -1387,6 +1387,11 @@ int LIBUSB_CALL libusb_clear_halt(libusb_device_handle *dev,
 	unsigned char endpoint);
 int LIBUSB_CALL libusb_reset_device(libusb_device_handle *dev);
 
+int LIBUSB_CALL libusb_alloc_streams(libusb_device_handle *dev,
+	uint32_t num_streams, unsigned char *endpoints, int num_endpoints);
+int LIBUSB_CALL libusb_free_streams(libusb_device_handle *dev,
+	unsigned char *endpoints, int num_endpoints);
+
 int LIBUSB_CALL libusb_kernel_driver_active(libusb_device_handle *dev,
 	int interface_number);
 int LIBUSB_CALL libusb_detach_kernel_driver(libusb_device_handle *dev,
diff --git a/libusb/libusbi.h b/libusb/libusbi.h
index 3d21406..225c273 100644
--- a/libusb/libusbi.h
+++ b/libusb/libusbi.h
@@ -843,6 +843,14 @@ struct usbi_os_backend {
 	 */
 	int (*reset_device)(struct libusb_device_handle *handle);
 
+	/* Alloc num_streams usb3 bulk streams on the passed in endpoints */
+	int (*alloc_streams)(struct libusb_device_handle *handle,
+		uint32_t num_streams, unsigned char *endpoints, int num_endpoints);
+
+	/* Free usb3 bulk streams allocated with alloc_streams */
+	int (*free_streams)(struct libusb_device_handle *handle,
+		unsigned char *endpoints, int num_endpoints);
+
 	/* Determine if a kernel driver is active on an interface. Optional.
 	 *
 	 * The presence of a kernel driver on an interface indicates that any
diff --git a/libusb/os/linux_usbfs.c b/libusb/os/linux_usbfs.c
index 5ad6129..2f6b4af 100644
--- a/libusb/os/linux_usbfs.c
+++ b/libusb/os/linux_usbfs.c
@@ -1495,6 +1495,56 @@ out:
 	return ret;
 }
 
+static int do_streams_ioctl(struct libusb_device_handle *handle, long req,
+	uint32_t num_streams, unsigned char *endpoints, int num_endpoints)
+{
+	int r, fd = _device_handle_priv(handle)->fd;
+	struct usbfs_streams *streams;
+
+	if (num_endpoints > 30) /* Max 15 in + 15 out eps */
+		return LIBUSB_ERROR_INVALID_PARAM;
+
+	streams = malloc(sizeof(struct usbfs_streams) + num_endpoints);
+	if (!streams)
+		return LIBUSB_ERROR_NO_MEM;
+
+	streams->num_streams = num_streams;
+	streams->num_eps = num_endpoints;
+	memcpy(streams->eps, endpoints, num_endpoints);
+
+	r = ioctl(fd, req, streams);
+
+	free(streams);
+
+	if (r < 0) {
+		if (errno == ENOTTY)
+			return LIBUSB_ERROR_NOT_SUPPORTED;
+		else if (errno == EINVAL)
+			return LIBUSB_ERROR_INVALID_PARAM;
+		else if (errno == ENODEV)
+			return LIBUSB_ERROR_NO_DEVICE;
+
+		usbi_err(HANDLE_CTX(handle),
+			"streams-ioctl failed error %d errno %d", r, errno);
+		return LIBUSB_ERROR_OTHER;
+	}
+	return r;
+}
+
+static int op_alloc_streams(struct libusb_device_handle *handle,
+	uint32_t num_streams, unsigned char *endpoints, int num_endpoints)
+{
+	return do_streams_ioctl(handle, IOCTL_USBFS_ALLOC_STREAMS,
+				num_streams, endpoints, num_endpoints);
+}
+
+static int op_free_streams(struct libusb_device_handle *handle,
+		unsigned char *endpoints, int num_endpoints)
+{
+	return do_streams_ioctl(handle, IOCTL_USBFS_FREE_STREAMS, 0,
+				endpoints, num_endpoints);
+}
+
 static int op_kernel_driver_active(struct libusb_device_handle *handle,
 	int interface)
 {
@@ -2596,6 +2646,9 @@ const struct usbi_os_backend linux_usbfs_backend = {
 	.clear_halt = op_clear_halt,
 	.reset_device = op_reset_device,
 
+	.alloc_streams = op_alloc_streams,
+	.free_streams = op_free_streams,
+
 	.kernel_driver_active = op_kernel_driver_active,
 	.detach_kernel_driver = op_detach_kernel_driver,
 	.attach_kernel_driver = op_attach_kernel_driver,
diff --git a/libusb/os/linux_usbfs.h b/libusb/os/linux_usbfs.h
index 1f5b191..de5186f 100644
--- a/libusb/os/linux_usbfs.h
+++ b/libusb/os/linux_usbfs.h
@@ -132,6 +132,12 @@ struct usbfs_disconnect_claim {
 	char driver[USBFS_MAXDRIVERNAME + 1];
 };
 
+struct usbfs_streams {
+	unsigned int num_streams; /* Not used by USBDEVFS_FREE_STREAMS */
+	unsigned int num_eps;
+	unsigned char eps[0];
+};
+
 #define IOCTL_USBFS_CONTROL	_IOWR('U', 0, struct usbfs_ctrltransfer)
 #define IOCTL_USBFS_BULK		_IOWR('U', 2, struct usbfs_bulktransfer)
 #define IOCTL_USBFS_RESETEP	_IOR('U', 3, unsigned int)
@@ -155,6 +161,8 @@ struct usbfs_disconnect_claim {
 #define IOCTL_USBFS_RELEASE_PORT	_IOR('U', 25, unsigned int)
 #define IOCTL_USBFS_GET_CAPABILITIES	_IOR('U', 26, __u32)
 #define IOCTL_USBFS_DISCONNECT_CLAIM	_IOR('U', 27, struct usbfs_disconnect_claim)
+#define IOCTL_USBFS_ALLOC_STREAMS	_IOR('U', 28, struct usbfs_streams)
+#define IOCTL_USBFS_FREE_STREAMS	_IOR('U', 29, struct usbfs_streams)
 
 extern usbi_mutex_static_t linux_hotplug_lock;
 
diff --git a/libusb/os/netbsd_usb.c b/libusb/os/netbsd_usb.c
index d43eea3..988d3c0 100644
--- a/libusb/os/netbsd_usb.c
+++ b/libusb/os/netbsd_usb.c
@@ -112,6 +112,9 @@ const struct usbi_os_backend netbsd_backend = {
 	netbsd_clear_halt,
 	netbsd_reset_device,
 
+	NULL,				/* alloc_streams */
+	NULL,				/* free_streams */
+
 	NULL,				/* kernel_driver_active() */
 	NULL,				/* detach_kernel_driver() */
 	NULL,				/* attach_kernel_driver() */
diff --git a/libusb/os/openbsd_usb.c b/libusb/os/openbsd_usb.c
index ef0b27b..d56c1af 100644
--- a/libusb/os/openbsd_usb.c
+++ b/libusb/os/openbsd_usb.c
@@ -115,6 +115,9 @@ const struct usbi_os_backend openbsd_backend = {
 	obsd_clear_halt,
 	obsd_reset_device,
 
+	NULL,				/* alloc_streams */
+	NULL,				/* free_streams */
+
 	NULL,				/* kernel_driver_active() */
 	NULL,				/* detach_kernel_driver() */
 	NULL,				/* attach_kernel_driver() */
diff --git a/libusb/os/wince_usb.c b/libusb/os/wince_usb.c
index c48d27d..656b1de 100644
--- a/libusb/os/wince_usb.c
+++ b/libusb/os/wince_usb.c
@@ -1005,6 +1005,9 @@ const struct usbi_os_backend wince_backend = {
         wince_clear_halt,
         wince_reset_device,
 
+	NULL,				/* alloc_streams */
+	NULL,				/* free_streams */
+
         wince_kernel_driver_active,
         wince_detach_kernel_driver,
         wince_attach_kernel_driver,
diff --git a/libusb/os/windows_usb.c b/libusb/os/windows_usb.c
index e130bc9..1a25d37 100644
--- a/libusb/os/windows_usb.c
+++ b/libusb/os/windows_usb.c
@@ -2317,6 +2317,9 @@ const struct usbi_os_backend windows_backend = {
 	windows_clear_halt,
 	windows_reset_device,
 
+	NULL,				/* alloc_streams */
+	NULL,				/* free_streams */
+
 	windows_kernel_driver_active,
 	windows_detach_kernel_driver,
 	windows_attach_kernel_driver,
diff --git a/libusb/version_nano.h b/libusb/version_nano.h
index ce329f2..f37c06f 100644
--- a/libusb/version_nano.h
+++ b/libusb/version_nano.h
@@ -1 +1 @@
-#define LIBUSB_NANO 10878
+#define LIBUSB_NANO 10879