diff --git a/libfprint/drivers/aes1610.c b/libfprint/drivers/aes1610.c
index 5aa14c3..5818ad4 100644
--- a/libfprint/drivers/aes1610.c
+++ b/libfprint/drivers/aes1610.c
@@ -128,15 +128,10 @@ static void generic_write_regv_cb(struct fp_img_dev *dev, int result,
  * away, then increment the SSM */
 static void generic_read_ignore_data(fpi_ssm *ssm, struct fp_dev *dev, size_t bytes)
 {
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	unsigned char *data;
 	int r;
 
-	if (!transfer) {
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
-
 	data = g_malloc(bytes);
 	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(dev), EP_IN, data, bytes,
 		generic_ignore_data_cb, ssm, BULK_TIMEOUT);
@@ -224,12 +219,7 @@ static void finger_det_reqs_cb(struct fp_img_dev *dev, int result, void *user_da
 		return;
 	}
 
-	transfer = libusb_alloc_transfer(0);
-	if (!transfer) {
-		fpi_imgdev_session_error(dev, -ENOMEM);
-		return;
-	}
-
+	transfer = fpi_usb_alloc();
 	data = g_malloc(19);
 	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_IN, data, 19,
 		finger_det_data_cb, dev, BULK_TIMEOUT);
@@ -666,14 +656,9 @@ static void capture_run_state(fpi_ssm *ssm, struct fp_dev *_dev, void *user_data
 				generic_write_regv_cb, ssm);
 		break;
 	case CAPTURE_READ_STRIP: ;
-		struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+		struct libusb_transfer *transfer = fpi_usb_alloc();
 		unsigned char *data;
 
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			break;
-		}
-
 		data = g_malloc(665);
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_IN, data, 665,
 			capture_read_strip_cb, ssm, BULK_TIMEOUT);
diff --git a/libfprint/drivers/aes2501.c b/libfprint/drivers/aes2501.c
index fa72e23..dc03493 100644
--- a/libfprint/drivers/aes2501.c
+++ b/libfprint/drivers/aes2501.c
@@ -115,12 +115,7 @@ static void read_regs_rq_cb(struct fp_img_dev *dev, int result, void *user_data)
 	if (result != 0)
 		goto err;
 
-	transfer = libusb_alloc_transfer(0);
-	if (!transfer) {
-		result = -ENOMEM;
-		goto err;
-	}
-
+	transfer = fpi_usb_alloc();
 	data = g_malloc(126);
 	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_IN, data, 126,
 		read_regs_data_cb, rdata, BULK_TIMEOUT);
@@ -207,15 +202,10 @@ static void generic_ignore_data_cb(struct libusb_transfer *transfer)
  * away, then increment the SSM */
 static void generic_read_ignore_data(fpi_ssm *ssm, struct fp_dev *dev, size_t bytes)
 {
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	unsigned char *data;
 	int r;
 
-	if (!transfer) {
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
-
 	data = g_malloc(bytes);
 	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(dev), EP_IN, data, bytes,
 		generic_ignore_data_cb, ssm, BULK_TIMEOUT);
@@ -325,12 +315,7 @@ static void finger_det_reqs_cb(struct fp_img_dev *dev, int result,
 		return;
 	}
 
-	transfer = libusb_alloc_transfer(0);
-	if (!transfer) {
-		fpi_imgdev_session_error(dev, -ENOMEM);
-		return;
-	}
-
+	transfer = fpi_usb_alloc();
 	data = g_malloc(20);
 	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_IN, data, 20,
 		finger_det_data_cb, dev, BULK_TIMEOUT);
@@ -548,14 +533,9 @@ static void capture_run_state(fpi_ssm *ssm, struct fp_dev *_dev, void *user_data
 				generic_write_regv_cb, ssm);
 		break;
 	case CAPTURE_READ_STRIP: ;
-		struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+		struct libusb_transfer *transfer = fpi_usb_alloc();
 		unsigned char *data;
 
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			break;
-		}
-
 		data = g_malloc(1705);
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_IN, data, 1705,
 			capture_read_strip_cb, ssm, BULK_TIMEOUT);
diff --git a/libfprint/drivers/aes2550.c b/libfprint/drivers/aes2550.c
index 5a26012..ce5b6c2 100644
--- a/libfprint/drivers/aes2550.c
+++ b/libfprint/drivers/aes2550.c
@@ -125,12 +125,7 @@ static void finger_det_reqs_cb(struct libusb_transfer *t)
 		goto exit_free_transfer;
 	}
 
-	transfer = libusb_alloc_transfer(0);
-	if (!transfer) {
-		fpi_imgdev_session_error(dev, -ENOMEM);
-		goto exit_free_transfer;
-	}
-
+	transfer = fpi_usb_alloc();
 	/* 2 bytes of result */
 	data = g_malloc(AES2550_EP_IN_BUF_SIZE);
 	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_IN, data, AES2550_EP_IN_BUF_SIZE,
@@ -158,11 +153,7 @@ static void start_finger_detection(struct fp_img_dev *dev)
 		return;
 	}
 
-	transfer = libusb_alloc_transfer(0);
-	if (!transfer) {
-		fpi_imgdev_session_error(dev, -ENOMEM);
-		return;
-	}
+	transfer = fpi_usb_alloc();
 	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_OUT, finger_det_reqs,
 		sizeof(finger_det_reqs), finger_det_reqs_cb, dev, BULK_TIMEOUT);
 	r = libusb_submit_transfer(transfer);
@@ -330,11 +321,8 @@ static void capture_run_state(fpi_ssm *ssm, struct fp_dev *_dev, void *user_data
 	switch (fpi_ssm_get_cur_state(ssm)) {
 	case CAPTURE_WRITE_REQS:
 	{
-		struct libusb_transfer *transfer = libusb_alloc_transfer(0);
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			return;
-		}
+		struct libusb_transfer *transfer = fpi_usb_alloc();
+
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_OUT, capture_reqs,
 			sizeof(capture_reqs), capture_reqs_cb, ssm, BULK_TIMEOUT);
 		r = libusb_submit_transfer(transfer);
@@ -346,14 +334,9 @@ static void capture_run_state(fpi_ssm *ssm, struct fp_dev *_dev, void *user_data
 	break;
 	case CAPTURE_READ_DATA:
 	{
-		struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+		struct libusb_transfer *transfer = fpi_usb_alloc();
 		unsigned char *data;
 
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			break;
-		}
-
 		data = g_malloc(AES2550_EP_IN_BUF_SIZE);
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_IN, data, AES2550_EP_IN_BUF_SIZE,
 			capture_read_data_cb, ssm, BULK_TIMEOUT);
@@ -368,11 +351,8 @@ static void capture_run_state(fpi_ssm *ssm, struct fp_dev *_dev, void *user_data
 	break;
 	case CAPTURE_SET_IDLE:
 	{
-		struct libusb_transfer *transfer = libusb_alloc_transfer(0);
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			return;
-		}
+		struct libusb_transfer *transfer = fpi_usb_alloc();
+
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_OUT, capture_set_idle_reqs,
 			sizeof(capture_set_idle_reqs), capture_set_idle_reqs_cb, ssm, BULK_TIMEOUT);
 		r = libusb_submit_transfer(transfer);
@@ -489,11 +469,8 @@ static void activate_run_state(fpi_ssm *ssm, struct fp_dev *_dev, void *user_dat
 	switch (fpi_ssm_get_cur_state(ssm)) {
 	case WRITE_INIT:
 	{
-		struct libusb_transfer *transfer = libusb_alloc_transfer(0);
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			return;
-		}
+		struct libusb_transfer *transfer = fpi_usb_alloc();
+
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_OUT, init_reqs,
 			sizeof(init_reqs), init_reqs_cb, ssm, BULK_TIMEOUT);
 		r = libusb_submit_transfer(transfer);
@@ -505,14 +482,9 @@ static void activate_run_state(fpi_ssm *ssm, struct fp_dev *_dev, void *user_dat
 	break;
 	case READ_DATA:
 	{
-		struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+		struct libusb_transfer *transfer = fpi_usb_alloc();
 		unsigned char *data;
 
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			break;
-		}
-
 		data = g_malloc(AES2550_EP_IN_BUF_SIZE);
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_IN, data, AES2550_EP_IN_BUF_SIZE,
 			init_read_data_cb, ssm, BULK_TIMEOUT);
@@ -527,11 +499,8 @@ static void activate_run_state(fpi_ssm *ssm, struct fp_dev *_dev, void *user_dat
 	break;
 	case CALIBRATE:
 	{
-		struct libusb_transfer *transfer = libusb_alloc_transfer(0);
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			return;
-		}
+		struct libusb_transfer *transfer = fpi_usb_alloc();
+
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_OUT, calibrate_reqs,
 			sizeof(calibrate_reqs), init_reqs_cb, ssm, BULK_TIMEOUT);
 		r = libusb_submit_transfer(transfer);
@@ -543,14 +512,9 @@ static void activate_run_state(fpi_ssm *ssm, struct fp_dev *_dev, void *user_dat
 	break;
 	case READ_CALIB_TABLE:
 	{
-		struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+		struct libusb_transfer *transfer = fpi_usb_alloc();
 		unsigned char *data;
 
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			break;
-		}
-
 		data = g_malloc(AES2550_EP_IN_BUF_SIZE);
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_IN, data, AES2550_EP_IN_BUF_SIZE,
 			calibrate_read_data_cb, ssm, BULK_TIMEOUT);
diff --git a/libfprint/drivers/aes3k.c b/libfprint/drivers/aes3k.c
index 6149e3a..ee80230 100644
--- a/libfprint/drivers/aes3k.c
+++ b/libfprint/drivers/aes3k.c
@@ -116,12 +116,7 @@ static void do_capture(struct fp_img_dev *dev)
 	unsigned char *data;
 	int r;
 
-	aesdev->img_trf = libusb_alloc_transfer(0);
-	if (!aesdev->img_trf) {
-		fpi_imgdev_session_error(dev, -EIO);
-		return;
-	}
-
+	aesdev->img_trf = fpi_usb_alloc();
 	data = g_malloc(aesdev->data_buflen);
 	libusb_fill_bulk_transfer(aesdev->img_trf, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_IN, data,
 		aesdev->data_buflen, img_cb, dev, 0);
diff --git a/libfprint/drivers/aeslib.c b/libfprint/drivers/aeslib.c
index 16cc903..3272540 100644
--- a/libfprint/drivers/aeslib.c
+++ b/libfprint/drivers/aeslib.c
@@ -24,9 +24,9 @@
 #include <errno.h>
 #include <string.h>
 
-#include <libusb.h>
 #include <glib.h>
 
+#include "fpi-usb.h"
 #include "assembling.h"
 #include "aeslib.h"
 
@@ -73,14 +73,9 @@ static int do_write_regv(struct write_regv_data *wdata, int upper_bound)
 	unsigned char *data = g_malloc(alloc_size);
 	unsigned int i;
 	size_t data_offset = 0;
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	int r;
 
-	if (!transfer) {
-		g_free(data);
-		return -ENOMEM;
-	}
-
 	for (i = offset; i < offset + num; i++) {
 		const struct aes_regwrite *regwrite = &wdata->regs[i];
 		data[data_offset++] = regwrite->reg;
diff --git a/libfprint/drivers/aesx660.c b/libfprint/drivers/aesx660.c
index d4c2662..b98ddf7 100644
--- a/libfprint/drivers/aesx660.c
+++ b/libfprint/drivers/aesx660.c
@@ -46,14 +46,9 @@ aesX660_send_cmd_timeout(fpi_ssm               *ssm,
 			 int                    timeout)
 {
 	struct fp_img_dev *dev = FP_IMG_DEV(_dev);
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	int r;
 
-	if (!transfer) {
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
-
 	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_OUT,
 		(unsigned char *)cmd, cmd_len,
 		callback, ssm, timeout);
@@ -82,15 +77,10 @@ aesX660_read_response(fpi_ssm               *ssm,
 		      libusb_transfer_cb_fn  callback)
 {
 	struct fp_img_dev *dev = FP_IMG_DEV(_dev);
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	unsigned char *data;
 	int r;
 
-	if (!transfer) {
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
-
 	data = g_malloc(buf_len);
 	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_IN,
 		data, buf_len,
diff --git a/libfprint/drivers/elan.c b/libfprint/drivers/elan.c
index 8f48bda..66fd240 100644
--- a/libfprint/drivers/elan.c
+++ b/libfprint/drivers/elan.c
@@ -380,22 +380,16 @@ static void elan_cmd_read(fpi_ssm *ssm, struct fp_img_dev *dev)
 		response_len =
 		    elandev->raw_frame_height * elandev->frame_width * 2;
 
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
-	if (!transfer) {
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
-	elandev->cur_transfer = transfer;
-
+	elandev->cur_transfer = fpi_usb_alloc();
 	g_free(elandev->last_read);
 	elandev->last_read = g_malloc(response_len);
 
-	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)),
+	libusb_fill_bulk_transfer(elandev->cur_transfer, fpi_dev_get_usb_dev(FP_DEV(dev)),
 				  elandev->cmd->response_in,
 				  elandev->last_read, response_len, elan_cmd_cb,
 				  ssm, elandev->cmd_timeout);
-	transfer->flags = LIBUSB_TRANSFER_FREE_TRANSFER;
-	int r = libusb_submit_transfer(transfer);
+	elandev->cur_transfer->flags = LIBUSB_TRANSFER_FREE_TRANSFER;
+	int r = libusb_submit_transfer(elandev->cur_transfer);
 	if (r < 0)
 		fpi_ssm_mark_failed(ssm, r);
 }
@@ -420,18 +414,12 @@ elan_run_cmd(fpi_ssm               *ssm,
 		return;
 	}
 
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
-	if (!transfer) {
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
-	elandev->cur_transfer = transfer;
-
-	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), ELAN_EP_CMD_OUT,
+	elandev->cur_transfer = fpi_usb_alloc();
+	libusb_fill_bulk_transfer(elandev->cur_transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), ELAN_EP_CMD_OUT,
 				  (char *) cmd->cmd, ELAN_CMD_LEN, elan_cmd_cb, ssm,
 				  elandev->cmd_timeout);
-	transfer->flags = LIBUSB_TRANSFER_FREE_TRANSFER;
-	int r = libusb_submit_transfer(transfer);
+	elandev->cur_transfer->flags = LIBUSB_TRANSFER_FREE_TRANSFER;
+	int r = libusb_submit_transfer(elandev->cur_transfer);
 	if (r < 0)
 		fpi_ssm_mark_failed(ssm, r);
 }
diff --git a/libfprint/drivers/etes603.c b/libfprint/drivers/etes603.c
index 2701cb0..97b6913 100644
--- a/libfprint/drivers/etes603.c
+++ b/libfprint/drivers/etes603.c
@@ -640,13 +640,10 @@ static int async_tx(struct fp_img_dev *idev, unsigned int ep, void *cb,
 	void *cb_arg)
 {
 	struct etes603_dev *dev = FP_INSTANCE_DATA(FP_DEV(idev));
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	unsigned char *buffer;
 	int length;
 
-	if (!transfer)
-		return -ENOMEM;
-
 	if (ep == EP_OUT) {
 		buffer = (unsigned char *)dev->req;
 		length = dev->req_len;
diff --git a/libfprint/drivers/upeksonly.c b/libfprint/drivers/upeksonly.c
index 8e9cc2f..c285bdf 100644
--- a/libfprint/drivers/upeksonly.c
+++ b/libfprint/drivers/upeksonly.c
@@ -583,13 +583,7 @@ sm_write_regs(fpi_ssm                     *ssm,
 	struct write_regs_data *wrdata = g_malloc(sizeof(*wrdata));
 	unsigned char *data;
 
-	wrdata->transfer = libusb_alloc_transfer(0);
-	if (!wrdata->transfer) {
-		g_free(wrdata);
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
-
+	wrdata->transfer = fpi_usb_alloc();
 	data = g_malloc(LIBUSB_CONTROL_SETUP_SIZE + 1);
 	libusb_fill_control_setup(data, 0x40, 0x0c, 0, 0, 1);
 	libusb_fill_control_transfer(wrdata->transfer,
@@ -621,15 +615,10 @@ sm_write_reg(fpi_ssm           *ssm,
 	     uint8_t            reg,
 	     uint8_t            value)
 {
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	unsigned char *data;
 	int r;
 
-	if (!transfer) {
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
-
 	fp_dbg("set %02x=%02x", reg, value);
 	data = g_malloc(LIBUSB_CONTROL_SETUP_SIZE + 1);
 	libusb_fill_control_setup(data, 0x40, 0x0c, 0, reg, 1);
@@ -671,15 +660,10 @@ sm_read_reg(fpi_ssm           *ssm,
 	    struct fp_img_dev *dev,
 	    uint8_t            reg)
 {
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	unsigned char *data;
 	int r;
 
-	if (!transfer) {
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
-
 	fp_dbg("read reg %02x", reg);
 	data = g_malloc(LIBUSB_CONTROL_SETUP_SIZE + 8);
 	libusb_fill_control_setup(data, 0xc0, 0x0c, 0, reg, 8);
@@ -723,15 +707,10 @@ static void
 sm_await_intr(fpi_ssm           *ssm,
 	      struct fp_img_dev *dev)
 {
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	unsigned char *data;
 	int r;
 
-	if (!transfer) {
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
-
 	G_DEBUG_HERE();
 	data = g_malloc(4);
 	libusb_fill_interrupt_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)),
@@ -1302,11 +1281,7 @@ static int dev_activate(struct fp_img_dev *dev, enum fp_imgdev_state state)
 	sdev->num_flying = 0;
 	for (i = 0; i < NUM_BULK_TRANSFERS; i++) {
 		unsigned char *data;
-		sdev->img_transfer[i] = libusb_alloc_transfer(0);
-		if (!sdev->img_transfer[i]) {
-			free_img_transfers(sdev);
-			return -ENOMEM;
-		}
+		sdev->img_transfer[i] = fpi_usb_alloc();
 		sdev->img_transfer_data[i].idx = i;
 		sdev->img_transfer_data[i].dev = dev;
 		data = g_malloc(4096);
diff --git a/libfprint/drivers/upektc.c b/libfprint/drivers/upektc.c
index 38a17a4..0042833 100644
--- a/libfprint/drivers/upektc.c
+++ b/libfprint/drivers/upektc.c
@@ -109,11 +109,8 @@ static void activate_run_state(fpi_ssm *ssm, struct fp_dev *_dev, void *user_dat
 	switch (fpi_ssm_get_cur_state(ssm)) {
 	case WRITE_INIT:
 	{
-		struct libusb_transfer *transfer = libusb_alloc_transfer(0);
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			return;
-		}
+		struct libusb_transfer *transfer = fpi_usb_alloc();
+
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), upekdev->ep_out,
 			(unsigned char*)upekdev->setup_commands[upekdev->init_idx].cmd,
 			UPEKTC_CMD_LEN, write_init_cb, ssm, BULK_TIMEOUT);
@@ -126,14 +123,9 @@ static void activate_run_state(fpi_ssm *ssm, struct fp_dev *_dev, void *user_dat
 	break;
 	case READ_DATA:
 	{
-		struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+		struct libusb_transfer *transfer = fpi_usb_alloc();
 		unsigned char *data;
 
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			break;
-		}
-
 		data = g_malloc(upekdev->setup_commands[upekdev->init_idx].response_len);
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), upekdev->ep_in, data,
 			upekdev->setup_commands[upekdev->init_idx].response_len,
@@ -228,12 +220,7 @@ static void finger_det_cmd_cb(struct libusb_transfer *t)
 		goto exit_free_transfer;
 	}
 
-	transfer = libusb_alloc_transfer(0);
-	if (!transfer) {
-		fpi_imgdev_session_error(dev, -ENOMEM);
-		goto exit_free_transfer;
-	}
-
+	transfer = fpi_usb_alloc();
 	data = g_malloc(IMAGE_SIZE);
 	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), upekdev->ep_in, data, IMAGE_SIZE,
 		finger_det_data_cb, dev, BULK_TIMEOUT);
@@ -260,11 +247,7 @@ static void start_finger_detection(struct fp_img_dev *dev)
 		return;
 	}
 
-	transfer = libusb_alloc_transfer(0);
-	if (!transfer) {
-		fpi_imgdev_session_error(dev, -ENOMEM);
-		return;
-	}
+	transfer = fpi_usb_alloc();
 	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), upekdev->ep_out,
 		(unsigned char *)scan_cmd, UPEKTC_CMD_LEN,
 		finger_det_cmd_cb, dev, BULK_TIMEOUT);
@@ -332,11 +315,8 @@ static void capture_run_state(fpi_ssm *ssm, struct fp_dev *_dev, void *user_data
 	switch (fpi_ssm_get_cur_state(ssm)) {
 	case CAPTURE_WRITE_CMD:
 	{
-		struct libusb_transfer *transfer = libusb_alloc_transfer(0);
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			return;
-		}
+		struct libusb_transfer *transfer = fpi_usb_alloc();
+
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), upekdev->ep_out,
 			(unsigned char *)scan_cmd, UPEKTC_CMD_LEN,
 			capture_cmd_cb, ssm, BULK_TIMEOUT);
@@ -349,14 +329,9 @@ static void capture_run_state(fpi_ssm *ssm, struct fp_dev *_dev, void *user_data
 	break;
 	case CAPTURE_READ_DATA:
 	{
-		struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+		struct libusb_transfer *transfer = fpi_usb_alloc();
 		unsigned char *data;
 
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			break;
-		}
-
 		data = g_malloc(IMAGE_SIZE);
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), upekdev->ep_in, data, IMAGE_SIZE,
 			capture_read_data_cb, ssm, BULK_TIMEOUT);
diff --git a/libfprint/drivers/upektc_img.c b/libfprint/drivers/upektc_img.c
index 9ca25cb..d749ac5 100644
--- a/libfprint/drivers/upektc_img.c
+++ b/libfprint/drivers/upektc_img.c
@@ -80,16 +80,11 @@ upektc_img_submit_req(fpi_ssm               *ssm,
 		      libusb_transfer_cb_fn  cb)
 {
 	struct upektc_img_dev *upekdev = FP_INSTANCE_DATA(FP_DEV(dev));
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	int r;
 
 	BUG_ON(buf_size > MAX_CMD_SIZE);
 
-	if (!transfer) {
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
-
 	transfer->flags |= LIBUSB_TRANSFER_FREE_TRANSFER;
 
 	memcpy(upekdev->cmd, buf, buf_size);
@@ -113,15 +108,10 @@ upektc_img_read_data(fpi_ssm               *ssm,
 		     size_t                 buf_offset,
 		     libusb_transfer_cb_fn  cb)
 {
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	struct upektc_img_dev *upekdev = FP_INSTANCE_DATA(FP_DEV(dev));
 	int r;
 
-	if (!transfer) {
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
-
 	BUG_ON(buf_size > MAX_RESPONSE_SIZE);
 
 	transfer->flags |= LIBUSB_TRANSFER_FREE_TRANSFER;
@@ -518,11 +508,7 @@ static void activate_run_state(fpi_ssm *ssm, struct fp_dev *dev, void *user_data
 	{
 		unsigned char *data;
 
-		transfer = libusb_alloc_transfer(0);
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			break;
-		}
+		transfer = fpi_usb_alloc();
 		transfer->flags |= LIBUSB_TRANSFER_FREE_BUFFER |
 			LIBUSB_TRANSFER_FREE_TRANSFER;
 
diff --git a/libfprint/drivers/upekts.c b/libfprint/drivers/upekts.c
index 98448e1..47eb0d2 100644
--- a/libfprint/drivers/upekts.c
+++ b/libfprint/drivers/upekts.c
@@ -90,7 +90,7 @@ static struct libusb_transfer *alloc_send_cmd_transfer(struct fp_dev *dev,
 	unsigned char seq_a, unsigned char seq_b, const unsigned char *data,
 	uint16_t len, libusb_transfer_cb_fn callback, void *user_data)
 {
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	uint16_t crc;
 	const char *ciao = "Ciao";
 
@@ -99,9 +99,6 @@ static struct libusb_transfer *alloc_send_cmd_transfer(struct fp_dev *dev,
 	size_t urblen = len + 9;
 	unsigned char *buf;
 
-	if (!transfer)
-		return NULL;
-
 	if (!data && len > 0) {
 		fp_err("len>0 but no data?");
 		return NULL;
@@ -367,12 +364,9 @@ static void read_msg_cb(struct libusb_transfer *transfer)
 	 * to read the remainder. This is handled below. */
 	if (len > MAX_DATA_IN_READ_BUF) {
 		int needed = len - MAX_DATA_IN_READ_BUF;
-		struct libusb_transfer *etransfer = libusb_alloc_transfer(0);
+		struct libusb_transfer *etransfer = fpi_usb_alloc();
 		int r;
 
-		if (!transfer)
-			goto err;
-
 		fp_dbg("didn't fit in buffer, need to extend by %d bytes", needed);
 		data = g_realloc((gpointer) data, MSG_READ_BUF_SIZE + needed);
 
@@ -407,14 +401,9 @@ out:
 static int __read_msg_async(struct read_msg_data *udata)
 {
 	unsigned char *buf = g_malloc(MSG_READ_BUF_SIZE);
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	int r;
 
-	if (!transfer) {
-		g_free(buf);
-		return -ENOMEM;
-	}
-
 	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(udata->dev), EP_IN, buf,
 		MSG_READ_BUF_SIZE, read_msg_cb, udata, TIMEOUT);
 	r = libusb_submit_transfer(transfer);
@@ -670,12 +659,7 @@ static void initsm_run_state(fpi_ssm *ssm, struct fp_dev *dev, void *user_data)
 	case WRITE_CTRL400: ;
 		unsigned char *data;
 
-		transfer = libusb_alloc_transfer(0);
-		if (!transfer) {
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			break;
-		}
-		
+		transfer = fpi_usb_alloc();
 		data = g_malloc(LIBUSB_CONTROL_SETUP_SIZE + 1);
 		libusb_fill_control_setup(data,
 			LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE, 0x0c, 0x100, 0x0400, 1);
diff --git a/libfprint/drivers/uru4000.c b/libfprint/drivers/uru4000.c
index 58455c0..0c76426 100644
--- a/libfprint/drivers/uru4000.c
+++ b/libfprint/drivers/uru4000.c
@@ -186,13 +186,10 @@ static int write_regs(struct fp_img_dev *dev, uint16_t first_reg,
 	void *user_data)
 {
 	struct write_regs_data *wrdata;
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	unsigned char *data;
 	int r;
 
-	if (!transfer)
-		return -ENOMEM;
-
 	wrdata = g_malloc(sizeof(*wrdata));
 	wrdata->dev = dev;
 	wrdata->callback = callback;
@@ -253,13 +250,10 @@ static int read_regs(struct fp_img_dev *dev, uint16_t first_reg,
 	uint16_t num_regs, read_regs_cb_fn callback, void *user_data)
 {
 	struct read_regs_data *rrdata;
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	unsigned char *data;
 	int r;
 
-	if (!transfer)
-		return -ENOMEM;
-
 	rrdata = g_malloc(sizeof(*rrdata));
 	rrdata->dev = dev;
 	rrdata->callback = callback;
@@ -428,13 +422,10 @@ out:
 static int start_irq_handler(struct fp_img_dev *dev)
 {
 	struct uru4k_dev *urudev = FP_INSTANCE_DATA(FP_DEV(dev));
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	unsigned char *data;
 	int r;
 
-	if (!transfer)
-		return -ENOMEM;
-	
 	data = g_malloc(IRQ_LENGTH);
 	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_INTR, data, IRQ_LENGTH,
 		irq_handler, dev, 0);
@@ -1236,7 +1227,7 @@ static int execute_state_change(struct fp_img_dev *dev)
 		fp_dbg("starting capture");
 		urudev->irq_cb = NULL;
 
-		urudev->img_transfer = libusb_alloc_transfer(0);
+		urudev->img_transfer = fpi_usb_alloc();
 		urudev->img_data = g_malloc(sizeof(struct uru4k_image));
 		urudev->img_enc_seed = rand();
 
diff --git a/libfprint/drivers/vcom5s.c b/libfprint/drivers/vcom5s.c
index 64aa64e..4ed71f6 100644
--- a/libfprint/drivers/vcom5s.c
+++ b/libfprint/drivers/vcom5s.c
@@ -91,15 +91,10 @@ sm_write_reg(fpi_ssm           *ssm,
 	     unsigned char      reg,
 	     unsigned char      value)
 {
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	unsigned char *data;
 	int r;
 	
-	if (!transfer) {
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
-
 	fp_dbg("set %02x=%02x", reg, value);
 	data = g_malloc(LIBUSB_CONTROL_SETUP_SIZE);
 	libusb_fill_control_setup(data, CTRL_OUT, reg, value, 0, 0);
@@ -132,14 +127,9 @@ sm_exec_cmd(fpi_ssm           *ssm,
 	    unsigned char      cmd,
 	    unsigned char      param)
 {
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	unsigned char *data;
 	int r;
-	
-	if (!transfer) {
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
 
 	fp_dbg("cmd %02x param %02x", cmd, param);
 	data = g_malloc(LIBUSB_CONTROL_SETUP_SIZE);
@@ -228,14 +218,9 @@ capture_iterate(fpi_ssm           *ssm,
 {
 	struct v5s_dev *vdev = FP_INSTANCE_DATA(FP_DEV(dev));
 	int iteration = vdev->capture_iteration;
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
+	struct libusb_transfer *transfer = fpi_usb_alloc();
 	int r;
 
-	if (!transfer) {
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
-
 	libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_IN,
 		vdev->capture_img->data + (RQ_SIZE * iteration), RQ_SIZE,
 		capture_cb, ssm, CTRL_TIMEOUT);
diff --git a/libfprint/drivers/vfs0050.c b/libfprint/drivers/vfs0050.c
index 1d8d7a1..a437df4 100644
--- a/libfprint/drivers/vfs0050.c
+++ b/libfprint/drivers/vfs0050.c
@@ -60,7 +60,7 @@ async_write(fpi_ssm           *ssm,
 	struct libusb_device_handle *usb_dev = fpi_dev_get_usb_dev(FP_DEV(dev));
 	struct vfs_dev_t *vdev = FP_INSTANCE_DATA(FP_DEV(dev));
 
-	vdev->transfer = libusb_alloc_transfer(0);
+	vdev->transfer = fpi_usb_alloc();
 	vdev->transfer->flags |= LIBUSB_TRANSFER_FREE_TRANSFER;
 	libusb_fill_bulk_transfer(vdev->transfer, usb_dev, 0x01, data, len,
 				  async_write_callback, ssm, VFS_USB_TIMEOUT);
@@ -109,7 +109,7 @@ async_read(fpi_ssm           *ssm,
 
 	ep |= LIBUSB_ENDPOINT_IN;
 
-	vdev->transfer = libusb_alloc_transfer(0);
+	vdev->transfer = fpi_usb_alloc();
 	vdev->transfer->flags |= LIBUSB_TRANSFER_FREE_TRANSFER;
 
 	/* 0x83 is the only interrupt endpoint */
@@ -166,7 +166,7 @@ static void async_abort(fpi_ssm *ssm, int ep)
 
 	ep |= LIBUSB_ENDPOINT_IN;
 
-	vdev->transfer = libusb_alloc_transfer(0);
+	vdev->transfer = fpi_usb_alloc();
 	vdev->transfer->flags |=
 	    LIBUSB_TRANSFER_FREE_TRANSFER | LIBUSB_TRANSFER_FREE_BUFFER;
 
@@ -578,7 +578,7 @@ static void activate_ssm(fpi_ssm *ssm, struct fp_dev *_dev, void *user_data)
 		}
 
 		/* Asyncronously enquire an interrupt */
-		vdev->transfer = libusb_alloc_transfer(0);
+		vdev->transfer = fpi_usb_alloc();
 		vdev->transfer->flags |= LIBUSB_TRANSFER_FREE_TRANSFER;
 		libusb_fill_interrupt_transfer(vdev->transfer, usb_dev, 0x83,
 					       vdev->interrupt,
@@ -628,7 +628,7 @@ static void activate_ssm(fpi_ssm *ssm, struct fp_dev *_dev, void *user_data)
 		}
 
 		/* Receive chunk of data */
-		vdev->transfer = libusb_alloc_transfer(0);
+		vdev->transfer = fpi_usb_alloc();
 		vdev->transfer->flags |= LIBUSB_TRANSFER_FREE_TRANSFER;
 		libusb_fill_bulk_transfer(vdev->transfer, usb_dev, 0x82,
 					  (void *)vdev->lines_buffer +
diff --git a/libfprint/drivers/vfs101.c b/libfprint/drivers/vfs101.c
index e4400f8..cf6980f 100644
--- a/libfprint/drivers/vfs101.c
+++ b/libfprint/drivers/vfs101.c
@@ -247,15 +247,7 @@ async_send(fpi_ssm           *ssm,
 	int r;
 
 	/* Allocation of transfer */
-	vdev->transfer = libusb_alloc_transfer(0);
-	if (!vdev->transfer)
-	{
-		/* Allocation transfer failed, return no memory error */
-		fp_err("allocation of usb transfer failed");
-		fpi_imgdev_session_error(dev, -ENOMEM);
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
+	vdev->transfer = fpi_usb_alloc();
 
 	/* Put sequential number into the buffer */
 	vdev->seqnum++;
@@ -335,15 +327,7 @@ async_recv(fpi_ssm           *ssm,
 	int r;
 
 	/* Allocation of transfer */
-	vdev->transfer = libusb_alloc_transfer(0);
-	if (!vdev->transfer)
-	{
-		/* Allocation transfer failed, return no memory error */
-		fp_err("allocation of usb transfer failed");
-		fpi_imgdev_session_error(dev, -ENOMEM);
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
+	vdev->transfer = fpi_usb_alloc();
 
 	/* Prepare bulk transfer */
 	libusb_fill_bulk_transfer(vdev->transfer, fpi_dev_get_usb_dev(FP_DEV(dev)), EP_IN(1), vdev->buffer, 0x0f, async_recv_cb, ssm, BULK_TIMEOUT);
@@ -438,15 +422,7 @@ async_load(fpi_ssm           *ssm,
 	int r;
 
 	/* Allocation of transfer */
-	vdev->transfer = libusb_alloc_transfer(0);
-	if (!vdev->transfer)
-	{
-		/* Allocation transfer failed, return no memory error */
-		fp_err("allocation of usb transfer failed");
-		fpi_imgdev_session_error(dev, -ENOMEM);
-		fpi_ssm_mark_failed(ssm, -ENOMEM);
-		return;
-	}
+	vdev->transfer = fpi_usb_alloc();
 
 	/* Append new data into the buffer */
 	buffer = vdev->buffer + vdev->length;
diff --git a/libfprint/drivers/vfs301_proto.c b/libfprint/drivers/vfs301_proto.c
index f96f411..7564f56 100644
--- a/libfprint/drivers/vfs301_proto.c
+++ b/libfprint/drivers/vfs301_proto.c
@@ -33,8 +33,8 @@
 #include <unistd.h>
 #include <stdlib.h>
 #include <glib.h>
-#include <libusb-1.0/libusb.h>
 
+#include "fpi-usb.h"
 #include "vfs301_proto.h"
 #include "vfs301_proto_fragments.h"
 
@@ -499,12 +499,7 @@ void vfs301_proto_process_event_start(
 	USB_RECV(VFS301_RECEIVE_ENDPOINT_DATA, 64);
 
 	/* now read the fingerprint data, while there are some */
-	transfer = libusb_alloc_transfer(0);
-	if (!transfer) {
-		dev->recv_progress = VFS301_FAILURE;
-		return;
-	}
-
+	transfer = fpi_usb_alloc();
 	dev->recv_progress = VFS301_ONGOING;
 	dev->recv_exp_amt = VFS301_FP_RECV_LEN_1;
 
diff --git a/libfprint/drivers/vfs5011.c b/libfprint/drivers/vfs5011.c
index 24e4868..2fcb822 100644
--- a/libfprint/drivers/vfs5011.c
+++ b/libfprint/drivers/vfs5011.c
@@ -189,13 +189,7 @@ static void usbexchange_loop(fpi_ssm *ssm, struct fp_dev *_dev, void *user_data)
 	switch (action->type) {
 	case ACTION_SEND:
 		fp_dbg("Sending %s", action->name);
-		transfer = libusb_alloc_transfer(0);
-		if (transfer == NULL) {
-			fp_err("Failed to allocate transfer");
-			fpi_imgdev_session_error(data->device, -ENOMEM);
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			return;
-		}
+		transfer = fpi_usb_alloc();
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(data->device)),
 					  action->endpoint, action->data,
 					  action->size, async_send_cb, ssm,
@@ -205,13 +199,7 @@ static void usbexchange_loop(fpi_ssm *ssm, struct fp_dev *_dev, void *user_data)
 
 	case ACTION_RECEIVE:
 		fp_dbg("Receiving %d bytes", action->size);
-		transfer = libusb_alloc_transfer(0);
-		if (transfer == NULL) {
-			fp_err("Failed to allocate transfer");
-			fpi_imgdev_session_error(data->device, -ENOMEM);
-			fpi_ssm_mark_failed(ssm, -ENOMEM);
-			return;
-		}
+		transfer = fpi_usb_alloc();
 		libusb_fill_bulk_transfer(transfer, fpi_dev_get_usb_dev(FP_DEV(data->device)),
 					  action->endpoint, data->receive_buf,
 					  action->size, async_recv_cb, ssm,
@@ -464,7 +452,7 @@ static int capture_chunk_async(struct vfs5011_data *data,
 		STOP_CHECK_LINES = 50
 	};
 
-	data->flying_transfer = libusb_alloc_transfer(0);
+	data->flying_transfer = fpi_usb_alloc();
 	libusb_fill_bulk_transfer(data->flying_transfer, handle, VFS5011_IN_ENDPOINT_DATA,
 				  data->capture_buffer,
 				  nline * VFS5011_LINE_SIZE,