From: Martin Ling <redacted>
Date: Sat, 21 Dec 2013 23:03:24 +0000 (+0000)
Subject: Use common usb_source_add and usb_source_remove functions.
X-Git-Tag: libsigrok-0.3.0~421
X-Git-Url: https://sigrok.org/gitweb/?p=libsigrok.git;a=commitdiff_plain;h=6c60facc190a03c50aa66d4b1d17c825fec5d20e

Use common usb_source_add and usb_source_remove functions.
---

diff --git a/hardware/common/usb.c b/hardware/common/usb.c
index bac420b3..249bce5a 100644
--- a/hardware/common/usb.c
+++ b/hardware/common/usb.c
@@ -243,3 +243,40 @@ SR_PRIV int sr_usb_open(libusb_context *usb_ctx, struct sr_usb_dev_inst *usb)
 
 	return ret;
 }
+
+SR_PRIV int usb_source_add(struct sr_context *ctx, int timeout,
+		sr_receive_data_callback_t cb, void *cb_data)
+{
+#ifdef _WIN32
+	sr_err("Operation not supported on Windows yet.");
+	return SR_ERR;
+#else
+	const struct libusb_pollfd **lupfd;
+	unsigned int i;
+
+	lupfd = libusb_get_pollfds(ctx->libusb_ctx);
+	for (i = 0; lupfd[i]; i++)
+		sr_source_add(lupfd[i]->fd, lupfd[i]->events, timeout, cb, cb_data);
+	free(lupfd);
+
+	return SR_OK;
+#endif
+}
+
+SR_PRIV int usb_source_remove(struct sr_context *ctx)
+{
+#ifdef _WIN32
+	sr_err("Operation not supported on Windows yet.");
+	return SR_ERR;
+#else
+	const struct libusb_pollfd **lupfd;
+	unsigned int i;
+
+	lupfd = libusb_get_pollfds(ctx->libusb_ctx);
+	for (i = 0; lupfd[i]; i++)
+		sr_source_remove(lupfd[i]->fd);
+	free(lupfd);
+
+	return SR_OK;
+#endif
+}
diff --git a/hardware/fx2lafw/api.c b/hardware/fx2lafw/api.c
index d10b6543..0c591428 100644
--- a/hardware/fx2lafw/api.c
+++ b/hardware/fx2lafw/api.c
@@ -468,7 +468,6 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 	struct drv_context *drvc;
 	struct sr_usb_dev_inst *usb;
 	struct libusb_transfer *transfer;
-	const struct libusb_pollfd **lupfd;
 	unsigned int i, timeout, num_transfers;
 	int ret;
 	unsigned char *buf;
@@ -524,17 +523,9 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 		devc->submitted_transfers++;
 	}
 
-	lupfd = libusb_get_pollfds(drvc->sr_ctx->libusb_ctx);
-	for (i = 0; lupfd[i]; i++);
-	if (!(devc->usbfd = g_try_malloc(sizeof(struct libusb_pollfd) * (i + 1))))
-		return SR_ERR;
-	for (i = 0; lupfd[i]; i++) {
-		sr_source_add(lupfd[i]->fd, lupfd[i]->events,
-			      timeout, receive_data, NULL);
-		devc->usbfd[i] = lupfd[i]->fd;
-	}
-	devc->usbfd[i] = -1;
-	free(lupfd);
+	devc->ctx = drvc->sr_ctx;
+
+	usb_source_add(devc->ctx, timeout, receive_data, NULL);
 
 	/* Send header packet to the session bus. */
 	std_session_send_df_header(cb_data, LOG_PREFIX);
diff --git a/hardware/fx2lafw/protocol.c b/hardware/fx2lafw/protocol.c
index 38ee13b5..303118d7 100644
--- a/hardware/fx2lafw/protocol.c
+++ b/hardware/fx2lafw/protocol.c
@@ -375,16 +375,13 @@ SR_PRIV void fx2lafw_abort_acquisition(struct dev_context *devc)
 static void finish_acquisition(struct dev_context *devc)
 {
 	struct sr_datafeed_packet packet;
-	int i;
 
 	/* Terminate session. */
 	packet.type = SR_DF_END;
 	sr_session_send(devc->cb_data, &packet);
 
 	/* Remove fds from polling. */
-	for (i = 0; devc->usbfd[i] != -1; i++)
-		sr_source_remove(devc->usbfd[i]);
-	g_free(devc->usbfd);
+	usb_source_remove(devc->ctx);
 
 	devc->num_transfers = 0;
 	g_free(devc->transfers);
diff --git a/hardware/fx2lafw/protocol.h b/hardware/fx2lafw/protocol.h
index 5ccf8c1c..76ef63d5 100644
--- a/hardware/fx2lafw/protocol.h
+++ b/hardware/fx2lafw/protocol.h
@@ -103,7 +103,7 @@ struct dev_context {
 	void *cb_data;
 	unsigned int num_transfers;
 	struct libusb_transfer **transfers;
-	int *usbfd;
+	struct sr_context *ctx;
 };
 
 SR_PRIV int fx2lafw_command_start_acquisition(libusb_device_handle *devhdl,
diff --git a/hardware/hantek-dso/api.c b/hardware/hantek-dso/api.c
index f74cefdf..3da04264 100644
--- a/hardware/hantek-dso/api.c
+++ b/hardware/hantek-dso/api.c
@@ -805,8 +805,7 @@ static int handle_event(int fd, int revents, void *cb_data)
 	struct timeval tv;
 	struct dev_context *devc;
 	struct drv_context *drvc = di->priv;
-	const struct libusb_pollfd **lupfd;
-	int num_probes, i;
+	int num_probes;
 	uint32_t trigger_offset;
 	uint8_t capturestate;
 
@@ -822,10 +821,7 @@ static int handle_event(int fd, int revents, void *cb_data)
 		 * TODO: Doesn't really cancel pending transfers so they might
 		 * come in after SR_DF_END is sent.
 		 */
-		lupfd = libusb_get_pollfds(drvc->sr_ctx->libusb_ctx);
-		for (i = 0; lupfd[i]; i++)
-			sr_source_remove(lupfd[i]->fd);
-		free(lupfd);
+		usb_source_remove(drvc->sr_ctx);
 
 		packet.type = SR_DF_END;
 		sr_session_send(sdi, &packet);
@@ -915,10 +911,8 @@ static int handle_event(int fd, int revents, void *cb_data)
 
 static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 {
-	const struct libusb_pollfd **lupfd;
 	struct dev_context *devc;
 	struct drv_context *drvc = di->priv;
-	int i;
 
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
@@ -938,11 +932,7 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 		return SR_ERR;
 
 	devc->dev_state = CAPTURE;
-	lupfd = libusb_get_pollfds(drvc->sr_ctx->libusb_ctx);
-	for (i = 0; lupfd[i]; i++)
-		sr_source_add(lupfd[i]->fd, lupfd[i]->events, TICK,
-				handle_event, (void *)sdi);
-	free(lupfd);
+	usb_source_add(drvc->sr_ctx, TICK, handle_event, (void *)sdi);
 
 	/* Send header packet to the session bus. */
 	std_session_send_df_header(cb_data, LOG_PREFIX);
diff --git a/hardware/ikalogic-scanalogic2/api.c b/hardware/ikalogic-scanalogic2/api.c
index 1fe869c3..a91afdbb 100644
--- a/hardware/ikalogic-scanalogic2/api.c
+++ b/hardware/ikalogic-scanalogic2/api.c
@@ -402,7 +402,6 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 {
-	const struct libusb_pollfd **pfd;
 	struct drv_context *drvc;
 	struct dev_context *devc;
 	uint16_t trigger_bytes, tmp;
@@ -473,34 +472,12 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 	tmp = GUINT16_TO_LE(devc->after_trigger_delay);
 	memcpy(devc->xfer_data_out + 10, &tmp, sizeof(tmp));
 
-	if (!(pfd = libusb_get_pollfds(drvc->sr_ctx->libusb_ctx))) {
-		sr_err("libusb_get_pollfds failed.");
-		return SR_ERR;
-	}
-
-	/* Count the number of file descriptors. */
-	for (devc->num_usbfd = 0; pfd[devc->num_usbfd]; devc->num_usbfd++);
-
-	if (!(devc->usbfd = g_try_malloc(devc->num_usbfd * sizeof(int)))) {
-		sr_err("File descriptor array malloc failed.");
-		free(pfd);
-		return SR_ERR_MALLOC;
-	}
-
 	if ((ret = libusb_submit_transfer(devc->xfer_out)) != 0) {
 		sr_err("Submit transfer failed: %s.", libusb_error_name(ret));
-		g_free(devc->usbfd);
 		return SR_ERR;
 	}
 
-	for (i = 0; i < devc->num_usbfd; i++) {
-		sr_source_add(pfd[i]->fd, pfd[i]->events, 100,
-			ikalogic_scanalogic2_receive_data, (void *)sdi);
-
-		devc->usbfd[i] = pfd[i]->fd;
-	}
-
-	free(pfd);
+	usb_source_add(drvc->sr_ctx, 100, ikalogic_scanalogic2_receive_data, (void *)sdi);
 
 	sr_dbg("Acquisition started successfully.");
 
diff --git a/hardware/ikalogic-scanalogic2/protocol.c b/hardware/ikalogic-scanalogic2/protocol.c
index 4c06e96d..87218de5 100644
--- a/hardware/ikalogic-scanalogic2/protocol.c
+++ b/hardware/ikalogic-scanalogic2/protocol.c
@@ -26,17 +26,14 @@ extern uint64_t sl2_samplerates[NUM_SAMPLERATES];
 
 static void stop_acquisition(struct sr_dev_inst *sdi)
 {
+	struct drv_context *drvc = sdi->driver->priv;
 	struct dev_context *devc;
 	struct sr_datafeed_packet packet;
-	unsigned int i;
 
 	devc = sdi->priv;
 
 	/* Remove USB file descriptors from polling. */
-	for (i = 0; i < devc->num_usbfd; i++)
-		sr_source_remove(devc->usbfd[i]);
-
-	g_free(devc->usbfd);
+	usb_source_remove(drvc->sr_ctx);
 
 	packet.type = SR_DF_END;
 	sr_session_send(devc->cb_data, &packet);
@@ -46,17 +43,14 @@ static void stop_acquisition(struct sr_dev_inst *sdi)
 
 static void abort_acquisition(struct sr_dev_inst *sdi)
 {
+	struct drv_context *drvc = sdi->driver->priv;
 	struct dev_context *devc;
 	struct sr_datafeed_packet packet;
-	unsigned int i;
 
 	devc = sdi->priv;
 
 	/* Remove USB file descriptors from polling. */
-	for (i = 0; i < devc->num_usbfd; i++)
-		sr_source_remove(devc->usbfd[i]);
-
-	g_free(devc->usbfd);
+	usb_source_remove(drvc->sr_ctx);
 
 	packet.type = SR_DF_END;
 	sr_session_send(devc->cb_data, &packet);
diff --git a/hardware/ikalogic-scanalogic2/protocol.h b/hardware/ikalogic-scanalogic2/protocol.h
index adc38592..8324204e 100644
--- a/hardware/ikalogic-scanalogic2/protocol.h
+++ b/hardware/ikalogic-scanalogic2/protocol.h
@@ -161,9 +161,6 @@ struct dev_context {
 	/* Array to provide an index based access to all probes. */
 	const struct sr_probe *probes[NUM_PROBES];
 
-	unsigned int num_usbfd;
-	int *usbfd;
-
 	struct libusb_transfer *xfer_in, *xfer_out;
 
 	/*
diff --git a/hardware/kecheng-kc-330b/api.c b/hardware/kecheng-kc-330b/api.c
index 9355e6dc..d9e647d1 100644
--- a/hardware/kecheng-kc-330b/api.c
+++ b/hardware/kecheng-kc-330b/api.c
@@ -432,9 +432,8 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi,
 	struct sr_config *src;
 	struct sr_usb_dev_inst *usb;
 	GVariant *gvar, *rational[2];
-	const struct libusb_pollfd **pfd;
 	const uint64_t *si;
-	int stored_mqflags, req_len, buf_len, len, ret, i;
+	int stored_mqflags, req_len, buf_len, len, ret;
 	unsigned char buf[9];
 
 	if (sdi->status != SR_ST_ACTIVE)
@@ -494,15 +493,8 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi,
 	if (!(devc->xfer = libusb_alloc_transfer(0)))
 		return SR_ERR;
 
-	pfd = libusb_get_pollfds(drvc->sr_ctx->libusb_ctx);
-	for (i = 0; pfd[i]; i++) {
-		/* Handle USB events every 10ms. */
-		sr_source_add(pfd[i]->fd, pfd[i]->events, 10,
-				kecheng_kc_330b_handle_events, (void *)sdi);
-		/* We'll need to remove this fd later. */
-		devc->usbfd[i] = pfd[i]->fd;
-	}
-	devc->usbfd[i] = -1;
+	usb_source_add(drvc->sr_ctx, 10,
+		kecheng_kc_330b_handle_events, (void *)sdi);
 
 	if (devc->data_source == DATA_SOURCE_LIVE) {
 		buf[0] = CMD_GET_LIVE_SPL;
diff --git a/hardware/kecheng-kc-330b/protocol.c b/hardware/kecheng-kc-330b/protocol.c
index a3a09514..c6263cde 100644
--- a/hardware/kecheng-kc-330b/protocol.c
+++ b/hardware/kecheng-kc-330b/protocol.c
@@ -34,7 +34,7 @@ SR_PRIV int kecheng_kc_330b_handle_events(int fd, int revents, void *cb_data)
 	struct timeval tv;
 	const uint64_t *intv_entry;
 	gint64 now, interval;
-	int offset, len, ret, i;
+	int offset, len, ret;
 	unsigned char buf[4];
 
 	(void)fd;
@@ -51,8 +51,7 @@ SR_PRIV int kecheng_kc_330b_handle_events(int fd, int revents, void *cb_data)
 
 	if (sdi->status == SR_ST_STOPPING) {
 		libusb_free_transfer(devc->xfer);
-		for (i = 0; devc->usbfd[i] != -1; i++)
-			sr_source_remove(devc->usbfd[i]);
+		usb_source_remove(drvc->sr_ctx);
 		packet.type = SR_DF_END;
 		sr_session_send(cb_data, &packet);
 		sdi->status = SR_ST_ACTIVE;
diff --git a/hardware/kecheng-kc-330b/protocol.h b/hardware/kecheng-kc-330b/protocol.h
index 6bf86efb..eabda85b 100644
--- a/hardware/kecheng-kc-330b/protocol.h
+++ b/hardware/kecheng-kc-330b/protocol.h
@@ -89,7 +89,6 @@ struct dev_context {
 	uint64_t num_samples;
 	uint64_t stored_samples;
 	void *cb_data;
-	int usbfd[10];
 	struct libusb_transfer *xfer;
 	unsigned char buf[128];
 
diff --git a/hardware/lascar-el-usb/api.c b/hardware/lascar-el-usb/api.c
index b699f283..74fd1e71 100644
--- a/hardware/lascar-el-usb/api.c
+++ b/hardware/lascar-el-usb/api.c
@@ -340,10 +340,9 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 	struct drv_context *drvc;
 	struct sr_usb_dev_inst *usb;
 	struct libusb_transfer *xfer_in, *xfer_out;
-	const struct libusb_pollfd **pfd;
 	struct timeval tv;
 	uint64_t interval;
-	int ret, i;
+	int ret;
 	unsigned char cmd[3], resp[4], *buf;
 
 	if (sdi->status != SR_ST_ACTIVE)
@@ -440,15 +439,7 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 	devc->log_size = xfer_in->buffer[1] + (xfer_in->buffer[2] << 8);
 	libusb_free_transfer(xfer_out);
 
-	pfd = libusb_get_pollfds(drvc->sr_ctx->libusb_ctx);
-	for (i = 0; pfd[i]; i++) {
-		/* Handle USB events every 100ms, for decent latency. */
-		sr_source_add(pfd[i]->fd, pfd[i]->events, 100,
-				lascar_el_usb_handle_events, (void *)sdi);
-		/* We'll need to remove this fd later. */
-		devc->usbfd[i] = pfd[i]->fd;
-	}
-	devc->usbfd[i] = -1;
+	usb_source_add(drvc->sr_ctx, 100, lascar_el_usb_handle_events, (void *)sdi);
 
 	buf = g_try_malloc(4096);
 	libusb_fill_bulk_transfer(xfer_in, usb->devhdl, LASCAR_EP_IN,
diff --git a/hardware/lascar-el-usb/protocol.c b/hardware/lascar-el-usb/protocol.c
index 3f9cbc88..032db07e 100644
--- a/hardware/lascar-el-usb/protocol.c
+++ b/hardware/lascar-el-usb/protocol.c
@@ -488,22 +488,18 @@ static void lascar_el_usb_dispatch(struct sr_dev_inst *sdi, unsigned char *buf,
 
 SR_PRIV int lascar_el_usb_handle_events(int fd, int revents, void *cb_data)
 {
-	struct dev_context *devc;
 	struct drv_context *drvc = di->priv;
 	struct sr_datafeed_packet packet;
 	struct sr_dev_inst *sdi;
 	struct timeval tv;
-	int i;
 
 	(void)fd;
 	(void)revents;
 
 	sdi = cb_data;
-	devc = sdi->priv;
 
 	if (sdi->status == SR_ST_STOPPING) {
-		for (i = 0; devc->usbfd[i] != -1; i++)
-			sr_source_remove(devc->usbfd[i]);
+		usb_source_remove(drvc->sr_ctx);
 
 		packet.type = SR_DF_END;
 		sr_session_send(cb_data, &packet);
diff --git a/hardware/lascar-el-usb/protocol.h b/hardware/lascar-el-usb/protocol.h
index be27f69c..16e826a0 100644
--- a/hardware/lascar-el-usb/protocol.h
+++ b/hardware/lascar-el-usb/protocol.h
@@ -45,7 +45,6 @@
 struct dev_context {
 	void *cb_data;
 	const struct elusb_profile *profile;
-	int usbfd[10];
 	/* Generic EL-USB */
 	unsigned char config[MAX_CONFIGBLOCK_SIZE];
 	unsigned int log_size;
diff --git a/hardware/saleae-logic16/api.c b/hardware/saleae-logic16/api.c
index e399729e..d2815f63 100644
--- a/hardware/saleae-logic16/api.c
+++ b/hardware/saleae-logic16/api.c
@@ -691,7 +691,6 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 	struct drv_context *drvc;
 	struct sr_usb_dev_inst *usb;
 	struct libusb_transfer *transfer;
-	const struct libusb_pollfd **lupfd;
 	unsigned int i, timeout, num_transfers;
 	int ret;
 	unsigned char *buf;
@@ -721,7 +720,6 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 	size = get_buffer_size(devc);
 	convsize = (size / devc->num_channels + 2) * 16;
 	devc->submitted_transfers = 0;
-	devc->usbfd = NULL;
 
 	devc->convbuffer_size = convsize;
 	if (!(devc->convbuffer = g_try_malloc(convsize))) {
@@ -771,21 +769,9 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 		devc->submitted_transfers++;
 	}
 
-	lupfd = libusb_get_pollfds(drvc->sr_ctx->libusb_ctx);
-	for (i = 0; lupfd[i]; i++);
-	devc->usbfd = g_try_malloc(sizeof(struct libusb_pollfd) * (i + 1));
-	if (!devc->usbfd) {
-		abort_acquisition(devc);
-		free(lupfd);
-		return SR_ERR;
-	}
-	for (i = 0; lupfd[i]; i++) {
-		sr_source_add(lupfd[i]->fd, lupfd[i]->events,
-			      timeout, receive_data, (void *)sdi);
-		devc->usbfd[i] = lupfd[i]->fd;
-	}
-	devc->usbfd[i] = -1;
-	free(lupfd);
+	devc->ctx = drvc->sr_ctx;
+
+	usb_source_add(devc->ctx, timeout, receive_data, (void *)sdi);
 
 	/* Send header packet to the session bus. */
 	std_session_send_df_header(cb_data, LOG_PREFIX);
diff --git a/hardware/saleae-logic16/protocol.c b/hardware/saleae-logic16/protocol.c
index 4cea180f..c7ff20c4 100644
--- a/hardware/saleae-logic16/protocol.c
+++ b/hardware/saleae-logic16/protocol.c
@@ -579,18 +579,13 @@ SR_PRIV int logic16_init_device(const struct sr_dev_inst *sdi)
 static void finish_acquisition(struct dev_context *devc)
 {
 	struct sr_datafeed_packet packet;
-	int i;
 
 	/* Terminate session. */
 	packet.type = SR_DF_END;
 	sr_session_send(devc->cb_data, &packet);
 
 	/* Remove fds from polling. */
-	if (devc->usbfd != NULL) {
-		for (i = 0; devc->usbfd[i] != -1; i++)
-			sr_source_remove(devc->usbfd[i]);
-		g_free(devc->usbfd);
-	}
+	usb_source_remove(devc->ctx);
 
 	devc->num_transfers = 0;
 	g_free(devc->transfers);
diff --git a/hardware/saleae-logic16/protocol.h b/hardware/saleae-logic16/protocol.h
index cd8380e3..6faa8b68 100644
--- a/hardware/saleae-logic16/protocol.h
+++ b/hardware/saleae-logic16/protocol.h
@@ -82,7 +82,7 @@ struct dev_context {
 	void *cb_data;
 	unsigned int num_transfers;
 	struct libusb_transfer **transfers;
-	int *usbfd;
+	struct sr_context *ctx;
 };
 
 SR_PRIV int logic16_setup_acquisition(const struct sr_dev_inst *sdi,
diff --git a/hardware/uni-t-ut32x/api.c b/hardware/uni-t-ut32x/api.c
index 8d4e7221..347149e0 100644
--- a/hardware/uni-t-ut32x/api.c
+++ b/hardware/uni-t-ut32x/api.c
@@ -297,8 +297,7 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi,
 	struct drv_context *drvc;
 	struct dev_context *devc;
 	struct sr_usb_dev_inst *usb;
-	const struct libusb_pollfd **pfd;
-	int len, ret, i;
+	int len, ret;
 	unsigned char cmd[2];
 
 	if (sdi->status != SR_ST_ACTIVE)
@@ -350,15 +349,7 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi,
 		return SR_ERR;
 	}
 
-	pfd = libusb_get_pollfds(drvc->sr_ctx->libusb_ctx);
-	for (i = 0; pfd[i]; i++) {
-		/* Handle USB events every 10ms. */
-		sr_source_add(pfd[i]->fd, pfd[i]->events, 10,
-				uni_t_ut32x_handle_events, (void *)sdi);
-		/* We'll need to remove this fd later. */
-		devc->usbfd[i] = pfd[i]->fd;
-	}
-	devc->usbfd[i] = -1;
+	usb_source_add(drvc->sr_ctx, 10, uni_t_ut32x_handle_events, (void *)sdi);
 
 	return SR_OK;
 }
diff --git a/hardware/uni-t-ut32x/protocol.c b/hardware/uni-t-ut32x/protocol.c
index 95f512b3..52c62892 100644
--- a/hardware/uni-t-ut32x/protocol.c
+++ b/hardware/uni-t-ut32x/protocol.c
@@ -198,7 +198,7 @@ SR_PRIV int uni_t_ut32x_handle_events(int fd, int revents, void *cb_data)
 	struct sr_datafeed_packet packet;
 	struct sr_usb_dev_inst *usb;
 	struct timeval tv;
-	int len, ret, i;
+	int len, ret;
 	unsigned char cmd[2];
 
 	(void)fd;
@@ -216,8 +216,7 @@ SR_PRIV int uni_t_ut32x_handle_events(int fd, int revents, void *cb_data)
 			NULL);
 
 	if (sdi->status == SR_ST_STOPPING) {
-		for (i = 0; devc->usbfd[i] != -1; i++)
-			sr_source_remove(devc->usbfd[i]);
+		usb_source_remove(drvc->sr_ctx);
 		packet.type = SR_DF_END;
 		sr_session_send(cb_data, &packet);
 
diff --git a/hardware/uni-t-ut32x/protocol.h b/hardware/uni-t-ut32x/protocol.h
index b070eb43..42cf01d1 100644
--- a/hardware/uni-t-ut32x/protocol.h
+++ b/hardware/uni-t-ut32x/protocol.h
@@ -63,7 +63,6 @@ struct dev_context {
 
 	/* Operational state */
 	uint64_t num_samples;
-	int usbfd[10];
 	unsigned char buf[8];
 	struct libusb_transfer *xfer;
 	void *cb_data;
diff --git a/hardware/victor-dmm/api.c b/hardware/victor-dmm/api.c
index 97e5f7bd..03462768 100644
--- a/hardware/victor-dmm/api.c
+++ b/hardware/victor-dmm/api.c
@@ -338,7 +338,6 @@ static int handle_events(int fd, int revents, void *cb_data)
 	struct sr_dev_inst *sdi;
 	struct timeval tv;
 	gint64 now;
-	int i;
 
 	(void)fd;
 	(void)revents;
@@ -353,8 +352,7 @@ static int handle_events(int fd, int revents, void *cb_data)
 	}
 
 	if (sdi->status == SR_ST_STOPPING) {
-		for (i = 0; devc->usbfd[i] != -1; i++)
-			sr_source_remove(devc->usbfd[i]);
+		usb_source_remove(drvc->sr_ctx);
 
 		dev_close(sdi);
 
@@ -373,10 +371,9 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 {
 	struct dev_context *devc;
 	struct drv_context *drvc = di->priv;
-	const struct libusb_pollfd **pfd;
 	struct sr_usb_dev_inst *usb;
 	struct libusb_transfer *transfer;
-	int ret, i;
+	int ret;
 	unsigned char *buf;
 
 	if (sdi->status != SR_ST_ACTIVE)
@@ -394,15 +391,7 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 	/* Send header packet to the session bus. */
 	std_session_send_df_header(cb_data, LOG_PREFIX);
 
-	pfd = libusb_get_pollfds(drvc->sr_ctx->libusb_ctx);
-	for (i = 0; pfd[i]; i++) {
-		/* Handle USB events every 100ms, for decent latency. */
-		sr_source_add(pfd[i]->fd, pfd[i]->events, 100,
-				handle_events, (void *)sdi);
-		/* We'll need to remove this fd later. */
-		devc->usbfd[i] = pfd[i]->fd;
-	}
-	devc->usbfd[i] = -1;
+	usb_source_add(drvc->sr_ctx, 100, handle_events, (void *)sdi);
 
 	buf = g_try_malloc(DMM_DATA_SIZE);
 	transfer = libusb_alloc_transfer(0);
diff --git a/hardware/victor-dmm/protocol.h b/hardware/victor-dmm/protocol.h
index b8573786..92539004 100644
--- a/hardware/victor-dmm/protocol.h
+++ b/hardware/victor-dmm/protocol.h
@@ -49,9 +49,6 @@ struct dev_context {
 	/** The current number of already received samples. */
 	uint64_t num_samples;
 	gint64 end_time;
-
-	/* Only requires 3 really. */
-	int usbfd[10];
 };
 
 SR_PRIV int victor_dmm_receive_data(struct sr_dev_inst *sdi, unsigned char *buf);
diff --git a/libsigrok-internal.h b/libsigrok-internal.h
index d9def32e..5c8d53de 100644
--- a/libsigrok-internal.h
+++ b/libsigrok-internal.h
@@ -268,6 +268,9 @@ SR_PRIV int ezusb_upload_firmware(libusb_device *dev, int configuration,
 #ifdef HAVE_LIBUSB_1_0
 SR_PRIV GSList *sr_usb_find(libusb_context *usb_ctx, const char *conn);
 SR_PRIV int sr_usb_open(libusb_context *usb_ctx, struct sr_usb_dev_inst *usb);
+SR_PRIV int usb_source_add(struct sr_context *ctx, int timeout,
+		sr_receive_data_callback_t cb, void *cb_data);
+SR_PRIV int usb_source_remove(struct sr_context *ctx);
 #endif
 
 /*--- hardware/common/scpi.c ------------------------------------------------*/