[libsigrok.git] / src / hardware / victor-dmm / api.c

/*
 * This file is part of the libsigrok project.
 *
 * Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <glib.h>
#include <libusb.h>
#include <stdlib.h>
#include <string.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"
#include "protocol.h"

#define VICTOR_VID 0x1244
#define VICTOR_PID 0xd237
#define VICTOR_VENDOR "Victor"
#define VICTOR_INTERFACE 0
#define VICTOR_ENDPOINT LIBUSB_ENDPOINT_IN | 1

SR_PRIV struct sr_dev_driver victor_dmm_driver_info;
static struct sr_dev_driver *di = &victor_dmm_driver_info;
static int dev_acquisition_stop(struct sr_dev_inst *sdi, void *cb_data);

static const uint32_t scanopts[] = {
	SR_CONF_CONN,
};

static const uint32_t devopts[] = {
	SR_CONF_MULTIMETER,
	SR_CONF_CONTINUOUS,
	SR_CONF_CONN | SR_CONF_GET,
	SR_CONF_LIMIT_SAMPLES | SR_CONF_SET,
	SR_CONF_LIMIT_MSEC | SR_CONF_SET,
};

static int init(struct sr_context *sr_ctx)
{
	return std_init(sr_ctx, di, LOG_PREFIX);
}

static GSList *scan(GSList *options)
{
	struct drv_context *drvc;
	struct dev_context *devc;
	struct sr_dev_inst *sdi;
	struct sr_channel *ch;
	struct libusb_device_descriptor des;
	libusb_device **devlist;
	GSList *devices;
	int ret, devcnt, i;

	(void)options;

	drvc = di->priv;

	devices = NULL;
	libusb_get_device_list(drvc->sr_ctx->libusb_ctx, &devlist);
	for (i = 0; devlist[i]; i++) {
		if ((ret = libusb_get_device_descriptor(devlist[i], &des)) != 0) {
			sr_warn("Failed to get device descriptor: %s",
					libusb_error_name(ret));
			continue;
		}

		if (des.idVendor != VICTOR_VID || des.idProduct != VICTOR_PID)
			continue;

		devcnt = g_slist_length(drvc->instances);
		if (!(sdi = sr_dev_inst_new(devcnt, SR_ST_INACTIVE,
				VICTOR_VENDOR, NULL, NULL)))
			return NULL;
		sdi->driver = di;

		if (!(devc = g_try_malloc0(sizeof(struct dev_context))))
			return NULL;
		sdi->priv = devc;

		if (!(ch = sr_channel_new(0, SR_CHANNEL_ANALOG, TRUE, "P1")))
			return NULL;
		sdi->channels = g_slist_append(NULL, ch);

		if (!(sdi->conn = sr_usb_dev_inst_new(libusb_get_bus_number(devlist[i]),
				libusb_get_device_address(devlist[i]), NULL)))
			return NULL;
		sdi->inst_type = SR_INST_USB;

		drvc->instances = g_slist_append(drvc->instances, sdi);
		devices = g_slist_append(devices, sdi);
	}
	libusb_free_device_list(devlist, 1);

	return devices;
}

static GSList *dev_list(void)
{
	return ((struct drv_context *)(di->priv))->instances;
}

static int dev_open(struct sr_dev_inst *sdi)
{
	struct drv_context *drvc = di->priv;
	struct sr_usb_dev_inst *usb;
	libusb_device **devlist;
	int ret, i;

	if (!di->priv) {
		sr_err("Driver was not initialized.");
		return SR_ERR;
	}

	usb = sdi->conn;

	libusb_get_device_list(drvc->sr_ctx->libusb_ctx, &devlist);
	for (i = 0; devlist[i]; i++) {
		if (libusb_get_bus_number(devlist[i]) != usb->bus
				|| libusb_get_device_address(devlist[i]) != usb->address)
			continue;
		if ((ret = libusb_open(devlist[i], &usb->devhdl))) {
			sr_err("Failed to open device: %s.", libusb_error_name(ret));
			return SR_ERR;
		}
		break;
	}
	libusb_free_device_list(devlist, 1);
	if (!devlist[i]) {
		sr_err("Device not found.");
		return SR_ERR;
	}

	/* The device reports as HID class, so the kernel would have
	 * claimed it. */
	if (libusb_kernel_driver_active(usb->devhdl, 0) == 1) {
		if ((ret = libusb_detach_kernel_driver(usb->devhdl, 0)) < 0) {
			sr_err("Failed to detach kernel driver: %s.",
			       libusb_error_name(ret));
			return SR_ERR;
		}
	}

	if ((ret = libusb_claim_interface(usb->devhdl,
			VICTOR_INTERFACE))) {
		sr_err("Failed to claim interface: %s.", libusb_error_name(ret));
		return SR_ERR;
	}
	sdi->status = SR_ST_ACTIVE;

	return SR_OK;
}

static int dev_close(struct sr_dev_inst *sdi)
{
	struct sr_usb_dev_inst *usb;

	if (!di->priv) {
		sr_err("Driver was not initialized.");
		return SR_ERR;
	}

	usb = sdi->conn;

	if (!usb->devhdl)
		/*  Nothing to do. */
		return SR_OK;

	libusb_release_interface(usb->devhdl, VICTOR_INTERFACE);
	libusb_close(usb->devhdl);
	usb->devhdl = NULL;
	sdi->status = SR_ST_INACTIVE;

	return SR_OK;
}

static int cleanup(void)
{
	int ret;
	struct drv_context *drvc;

	if (!(drvc = di->priv))
		/* Can get called on an unused driver, doesn't matter. */
		return SR_OK;


	ret = std_dev_clear(di, NULL);
	g_free(drvc);
	di->priv = NULL;

	return ret;
}

static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
		const struct sr_channel_group *cg)
{
	struct sr_usb_dev_inst *usb;
	char str[128];

	(void)cg;

	switch (key) {
	case SR_CONF_CONN:
		if (!sdi || !sdi->conn)
			return SR_ERR_ARG;
		usb = sdi->conn;
		snprintf(str, 128, "%d.%d", usb->bus, usb->address);
		*data = g_variant_new_string(str);
		break;
	default:
		return SR_ERR_NA;
	}

	return SR_OK;
}

static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
		const struct sr_channel_group *cg)
{
	struct dev_context *devc;
	gint64 now;
	int ret;

	(void)cg;

	if (sdi->status != SR_ST_ACTIVE)
		return SR_ERR_DEV_CLOSED;

	if (!di->priv) {
		sr_err("Driver was not initialized.");
		return SR_ERR;
	}

	devc = sdi->priv;
	ret = SR_OK;
	switch (key) {
	case SR_CONF_LIMIT_MSEC:
		devc->limit_msec = g_variant_get_uint64(data);
		now = g_get_monotonic_time() / 1000;
		devc->end_time = now + devc->limit_msec;
		sr_dbg("Setting time limit to %" PRIu64 "ms.",
		       devc->limit_msec);
		break;
	case SR_CONF_LIMIT_SAMPLES:
		devc->limit_samples = g_variant_get_uint64(data);
		sr_dbg("Setting sample limit to %" PRIu64 ".",
		       devc->limit_samples);
		break;
	default:
		ret = SR_ERR_NA;
	}

	return ret;
}

static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
		const struct sr_channel_group *cg)
{
	(void)sdi;
	(void)cg;

	switch (key) {
	case SR_CONF_SCAN_OPTIONS:
		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
				scanopts, ARRAY_SIZE(scanopts), sizeof(uint32_t));
		break;
	case SR_CONF_DEVICE_OPTIONS:
		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
				devopts, ARRAY_SIZE(devopts), sizeof(uint32_t));
		break;
	default:
		return SR_ERR_NA;
	}

	return SR_OK;
}

static void receive_transfer(struct libusb_transfer *transfer)
{
	struct dev_context *devc;
	struct sr_dev_inst *sdi;
	int ret;

	sdi = transfer->user_data;
	devc = sdi->priv;
	if (transfer->status == LIBUSB_TRANSFER_NO_DEVICE) {
		/* USB device was unplugged. */
		dev_acquisition_stop(sdi, sdi);
	} else if (transfer->status == LIBUSB_TRANSFER_COMPLETED) {
		sr_dbg("Got %d-byte packet.", transfer->actual_length);
		if (transfer->actual_length == DMM_DATA_SIZE) {
			victor_dmm_receive_data(sdi, transfer->buffer);
			if (devc->limit_samples) {
				if (devc->num_samples >= devc->limit_samples)
					dev_acquisition_stop(sdi, sdi);
			}
		}
	}
	/* Anything else is either an error or a timeout, which is fine:
	 * we were just going to send another transfer request anyway. */

	if (sdi->status == SR_ST_ACTIVE) {
		/* Send the same request again. */
		if ((ret = libusb_submit_transfer(transfer) != 0)) {
			sr_err("Unable to resubmit transfer: %s.",
			       libusb_error_name(ret));
			g_free(transfer->buffer);
			libusb_free_transfer(transfer);
			dev_acquisition_stop(sdi, sdi);
		}
	} else {
		/* This was the last transfer we're going to receive, so
		 * clean up now. */
		g_free(transfer->buffer);
		libusb_free_transfer(transfer);
	}
}

static int 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;
	gint64 now;

	(void)fd;
	(void)revents;

	sdi = cb_data;
	devc = sdi->priv;

	if (devc->limit_msec) {
		now = g_get_monotonic_time() / 1000;
		if (now > devc->end_time)
			dev_acquisition_stop(sdi, sdi);
	}

	if (sdi->status == SR_ST_STOPPING) {
		usb_source_remove(sdi->session, drvc->sr_ctx);

		dev_close(sdi);

		packet.type = SR_DF_END;
		sr_session_send(cb_data, &packet);
	}

	memset(&tv, 0, sizeof(struct timeval));
	libusb_handle_events_timeout_completed(drvc->sr_ctx->libusb_ctx, &tv,
					       NULL);

	return TRUE;
}

static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
{
	struct dev_context *devc;
	struct drv_context *drvc = di->priv;
	struct sr_usb_dev_inst *usb;
	struct libusb_transfer *transfer;
	int ret;
	unsigned char *buf;

	if (sdi->status != SR_ST_ACTIVE)
		return SR_ERR_DEV_CLOSED;

	if (!di->priv) {
		sr_err("Driver was not initialized.");
		return SR_ERR;
	}

	devc = sdi->priv;
	usb = sdi->conn;
	devc->cb_data = cb_data;

	/* Send header packet to the session bus. */
	std_session_send_df_header(cb_data, LOG_PREFIX);

	usb_source_add(sdi->session, drvc->sr_ctx, 100,
			handle_events, (void *)sdi);

	buf = g_try_malloc(DMM_DATA_SIZE);
	transfer = libusb_alloc_transfer(0);
	/* Each transfer request gets 100ms to arrive before it's restarted.
	 * The device only sends 1 transfer/second no matter how many
	 * times you ask, but we want to keep step with the USB events
	 * handling above. */
	libusb_fill_interrupt_transfer(transfer, usb->devhdl,
			VICTOR_ENDPOINT, buf, DMM_DATA_SIZE, receive_transfer,
			cb_data, 100);
	if ((ret = libusb_submit_transfer(transfer) != 0)) {
		sr_err("Unable to submit transfer: %s.", libusb_error_name(ret));
		libusb_free_transfer(transfer);
		g_free(buf);
		return SR_ERR;
	}

	return SR_OK;
}

static int dev_acquisition_stop(struct sr_dev_inst *sdi, void *cb_data)
{
	(void)cb_data;

	if (!di->priv) {
		sr_err("Driver was not initialized.");
		return SR_ERR;
	}

	if (sdi->status != SR_ST_ACTIVE) {
		sr_err("Device not active, can't stop acquisition.");
		return SR_ERR;
	}

	sdi->status = SR_ST_STOPPING;

	return SR_OK;
}

SR_PRIV struct sr_dev_driver victor_dmm_driver_info = {
	.name = "victor-dmm",
	.longname = "Victor DMMs",
	.api_version = 1,
	.init = init,
	.cleanup = cleanup,
	.scan = scan,
	.dev_list = dev_list,
	.dev_clear = NULL,
	.config_get = config_get,
	.config_set = config_set,
	.config_list = config_list,
	.dev_open = dev_open,
	.dev_close = dev_close,
	.dev_acquisition_start = dev_acquisition_start,
	.dev_acquisition_stop = dev_acquisition_stop,
	.priv = NULL,
};
Commit	Line	Data
	1	/*
	2	* This file is part of the libsigrok project.
	3	*
	4	* Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
	5	*
	6	* This program is free software: you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation, either version 3 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program. If not, see <http://www.gnu.org/licenses/>.
	18	*/
	19
	20	#include <glib.h>
	21	#include <libusb.h>
	22	#include <stdlib.h>
	23	#include <string.h>
	24	#include "libsigrok.h"
	25	#include "libsigrok-internal.h"
	26	#include "protocol.h"
	27
	28	#define VICTOR_VID 0x1244
	29	#define VICTOR_PID 0xd237
	30	#define VICTOR_VENDOR "Victor"
	31	#define VICTOR_INTERFACE 0
	32	#define VICTOR_ENDPOINT LIBUSB_ENDPOINT_IN \| 1
	33
	34	SR_PRIV struct sr_dev_driver victor_dmm_driver_info;
	35	static struct sr_dev_driver *di = &victor_dmm_driver_info;
	36	static int dev_acquisition_stop(struct sr_dev_inst sdi, void cb_data);
	37
	38	static const uint32_t scanopts[] = {
	39	SR_CONF_CONN,
	40	};
	41
	42	static const uint32_t devopts[] = {
	43	SR_CONF_MULTIMETER,
	44	SR_CONF_CONTINUOUS,
	45	SR_CONF_CONN \| SR_CONF_GET,
	46	SR_CONF_LIMIT_SAMPLES \| SR_CONF_SET,
	47	SR_CONF_LIMIT_MSEC \| SR_CONF_SET,
	48	};
	49
	50	static int init(struct sr_context *sr_ctx)
	51	{
	52	return std_init(sr_ctx, di, LOG_PREFIX);
	53	}
	54
	55	static GSList scan(GSList options)
	56	{
	57	struct drv_context *drvc;
	58	struct dev_context *devc;
	59	struct sr_dev_inst *sdi;
	60	struct sr_channel *ch;
	61	struct libusb_device_descriptor des;
	62	libusb_device **devlist;
	63	GSList *devices;
	64	int ret, devcnt, i;
	65
	66	(void)options;
	67
	68	drvc = di->priv;
	69
	70	devices = NULL;
	71	libusb_get_device_list(drvc->sr_ctx->libusb_ctx, &devlist);
	72	for (i = 0; devlist[i]; i++) {
	73	if ((ret = libusb_get_device_descriptor(devlist[i], &des)) != 0) {
	74	sr_warn("Failed to get device descriptor: %s",
	75	libusb_error_name(ret));
	76	continue;
	77	}
	78
	79	if (des.idVendor != VICTOR_VID \|\| des.idProduct != VICTOR_PID)
	80	continue;
	81
	82	devcnt = g_slist_length(drvc->instances);
	83	if (!(sdi = sr_dev_inst_new(devcnt, SR_ST_INACTIVE,
	84	VICTOR_VENDOR, NULL, NULL)))
	85	return NULL;
	86	sdi->driver = di;
	87
	88	if (!(devc = g_try_malloc0(sizeof(struct dev_context))))
	89	return NULL;
	90	sdi->priv = devc;
	91
	92	if (!(ch = sr_channel_new(0, SR_CHANNEL_ANALOG, TRUE, "P1")))
	93	return NULL;
	94	sdi->channels = g_slist_append(NULL, ch);
	95
	96	if (!(sdi->conn = sr_usb_dev_inst_new(libusb_get_bus_number(devlist[i]),
	97	libusb_get_device_address(devlist[i]), NULL)))
	98	return NULL;
	99	sdi->inst_type = SR_INST_USB;
	100
	101	drvc->instances = g_slist_append(drvc->instances, sdi);
	102	devices = g_slist_append(devices, sdi);
	103	}
	104	libusb_free_device_list(devlist, 1);
	105
	106	return devices;
	107	}
	108
	109	static GSList *dev_list(void)
	110	{
	111	return ((struct drv_context *)(di->priv))->instances;
	112	}
	113
	114	static int dev_open(struct sr_dev_inst *sdi)
	115	{
	116	struct drv_context *drvc = di->priv;
	117	struct sr_usb_dev_inst *usb;
	118	libusb_device **devlist;
	119	int ret, i;
	120
	121	if (!di->priv) {
	122	sr_err("Driver was not initialized.");
	123	return SR_ERR;
	124	}
	125
	126	usb = sdi->conn;
	127
	128	libusb_get_device_list(drvc->sr_ctx->libusb_ctx, &devlist);
	129	for (i = 0; devlist[i]; i++) {
	130	if (libusb_get_bus_number(devlist[i]) != usb->bus
	131	\|\| libusb_get_device_address(devlist[i]) != usb->address)
	132	continue;
	133	if ((ret = libusb_open(devlist[i], &usb->devhdl))) {
	134	sr_err("Failed to open device: %s.", libusb_error_name(ret));
	135	return SR_ERR;
	136	}
	137	break;
	138	}
	139	libusb_free_device_list(devlist, 1);
	140	if (!devlist[i]) {
	141	sr_err("Device not found.");
	142	return SR_ERR;
	143	}
	144
	145	/* The device reports as HID class, so the kernel would have
	146	* claimed it. */
	147	if (libusb_kernel_driver_active(usb->devhdl, 0) == 1) {
	148	if ((ret = libusb_detach_kernel_driver(usb->devhdl, 0)) < 0) {
	149	sr_err("Failed to detach kernel driver: %s.",
	150	libusb_error_name(ret));
	151	return SR_ERR;
	152	}
	153	}
	154
	155	if ((ret = libusb_claim_interface(usb->devhdl,
	156	VICTOR_INTERFACE))) {
	157	sr_err("Failed to claim interface: %s.", libusb_error_name(ret));
	158	return SR_ERR;
	159	}
	160	sdi->status = SR_ST_ACTIVE;
	161
	162	return SR_OK;
	163	}
	164
	165	static int dev_close(struct sr_dev_inst *sdi)
	166	{
	167	struct sr_usb_dev_inst *usb;
	168
	169	if (!di->priv) {
	170	sr_err("Driver was not initialized.");
	171	return SR_ERR;
	172	}
	173
	174	usb = sdi->conn;
	175
	176	if (!usb->devhdl)
	177	/* Nothing to do. */
	178	return SR_OK;
	179
	180	libusb_release_interface(usb->devhdl, VICTOR_INTERFACE);
	181	libusb_close(usb->devhdl);
	182	usb->devhdl = NULL;
	183	sdi->status = SR_ST_INACTIVE;
	184
	185	return SR_OK;
	186	}
	187
	188	static int cleanup(void)
	189	{
	190	int ret;
	191	struct drv_context *drvc;
	192
	193	if (!(drvc = di->priv))
	194	/* Can get called on an unused driver, doesn't matter. */
	195	return SR_OK;
	196
	197
	198	ret = std_dev_clear(di, NULL);
	199	g_free(drvc);
	200	di->priv = NULL;
	201
	202	return ret;
	203	}
	204
	205	static int config_get(uint32_t key, GVariant *data, const struct sr_dev_inst sdi,
	206	const struct sr_channel_group *cg)
	207	{
	208	struct sr_usb_dev_inst *usb;
	209	char str[128];
	210
	211	(void)cg;
	212
	213	switch (key) {
	214	case SR_CONF_CONN:
	215	if (!sdi \|\| !sdi->conn)
	216	return SR_ERR_ARG;
	217	usb = sdi->conn;
	218	snprintf(str, 128, "%d.%d", usb->bus, usb->address);
	219	*data = g_variant_new_string(str);
	220	break;
	221	default:
	222	return SR_ERR_NA;
	223	}
	224
	225	return SR_OK;
	226	}
	227
	228	static int config_set(uint32_t key, GVariant data, const struct sr_dev_inst sdi,
	229	const struct sr_channel_group *cg)
	230	{
	231	struct dev_context *devc;
	232	gint64 now;
	233	int ret;
	234
	235	(void)cg;
	236
	237	if (sdi->status != SR_ST_ACTIVE)
	238	return SR_ERR_DEV_CLOSED;
	239
	240	if (!di->priv) {
	241	sr_err("Driver was not initialized.");
	242	return SR_ERR;
	243	}
	244
	245	devc = sdi->priv;
	246	ret = SR_OK;
	247	switch (key) {
	248	case SR_CONF_LIMIT_MSEC:
	249	devc->limit_msec = g_variant_get_uint64(data);
	250	now = g_get_monotonic_time() / 1000;
	251	devc->end_time = now + devc->limit_msec;
	252	sr_dbg("Setting time limit to %" PRIu64 "ms.",
	253	devc->limit_msec);
	254	break;
	255	case SR_CONF_LIMIT_SAMPLES:
	256	devc->limit_samples = g_variant_get_uint64(data);
	257	sr_dbg("Setting sample limit to %" PRIu64 ".",
	258	devc->limit_samples);
	259	break;
	260	default:
	261	ret = SR_ERR_NA;
	262	}
	263
	264	return ret;
	265	}
	266
	267	static int config_list(uint32_t key, GVariant *data, const struct sr_dev_inst sdi,
	268	const struct sr_channel_group *cg)
	269	{
	270	(void)sdi;
	271	(void)cg;
	272
	273	switch (key) {
	274	case SR_CONF_SCAN_OPTIONS:
	275	*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
	276	scanopts, ARRAY_SIZE(scanopts), sizeof(uint32_t));
	277	break;
	278	case SR_CONF_DEVICE_OPTIONS:
	279	*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
	280	devopts, ARRAY_SIZE(devopts), sizeof(uint32_t));
	281	break;
	282	default:
	283	return SR_ERR_NA;
	284	}
	285
	286	return SR_OK;
	287	}
	288
	289	static void receive_transfer(struct libusb_transfer *transfer)
	290	{
	291	struct dev_context *devc;
	292	struct sr_dev_inst *sdi;
	293	int ret;
	294
	295	sdi = transfer->user_data;
	296	devc = sdi->priv;
	297	if (transfer->status == LIBUSB_TRANSFER_NO_DEVICE) {
	298	/* USB device was unplugged. */
	299	dev_acquisition_stop(sdi, sdi);
	300	} else if (transfer->status == LIBUSB_TRANSFER_COMPLETED) {
	301	sr_dbg("Got %d-byte packet.", transfer->actual_length);
	302	if (transfer->actual_length == DMM_DATA_SIZE) {
	303	victor_dmm_receive_data(sdi, transfer->buffer);
	304	if (devc->limit_samples) {
	305	if (devc->num_samples >= devc->limit_samples)
	306	dev_acquisition_stop(sdi, sdi);
	307	}
	308	}
	309	}
	310	/* Anything else is either an error or a timeout, which is fine:
	311	* we were just going to send another transfer request anyway. */
	312
	313	if (sdi->status == SR_ST_ACTIVE) {
	314	/* Send the same request again. */
	315	if ((ret = libusb_submit_transfer(transfer) != 0)) {
	316	sr_err("Unable to resubmit transfer: %s.",
	317	libusb_error_name(ret));
	318	g_free(transfer->buffer);
	319	libusb_free_transfer(transfer);
	320	dev_acquisition_stop(sdi, sdi);
	321	}
	322	} else {
	323	/* This was the last transfer we're going to receive, so
	324	* clean up now. */
	325	g_free(transfer->buffer);
	326	libusb_free_transfer(transfer);
	327	}
	328	}
	329
	330	static int handle_events(int fd, int revents, void *cb_data)
	331	{
	332	struct dev_context *devc;
	333	struct drv_context *drvc = di->priv;
	334	struct sr_datafeed_packet packet;
	335	struct sr_dev_inst *sdi;
	336	struct timeval tv;
	337	gint64 now;
	338
	339	(void)fd;
	340	(void)revents;
	341
	342	sdi = cb_data;
	343	devc = sdi->priv;
	344
	345	if (devc->limit_msec) {
	346	now = g_get_monotonic_time() / 1000;
	347	if (now > devc->end_time)
	348	dev_acquisition_stop(sdi, sdi);
	349	}
	350
	351	if (sdi->status == SR_ST_STOPPING) {
	352	usb_source_remove(sdi->session, drvc->sr_ctx);
	353
	354	dev_close(sdi);
	355
	356	packet.type = SR_DF_END;
	357	sr_session_send(cb_data, &packet);
	358	}
	359
	360	memset(&tv, 0, sizeof(struct timeval));
	361	libusb_handle_events_timeout_completed(drvc->sr_ctx->libusb_ctx, &tv,
	362	NULL);
	363
	364	return TRUE;
	365	}
	366
	367	static int dev_acquisition_start(const struct sr_dev_inst sdi, void cb_data)
	368	{
	369	struct dev_context *devc;
	370	struct drv_context *drvc = di->priv;
	371	struct sr_usb_dev_inst *usb;
	372	struct libusb_transfer *transfer;
	373	int ret;
	374	unsigned char *buf;
	375
	376	if (sdi->status != SR_ST_ACTIVE)
	377	return SR_ERR_DEV_CLOSED;
	378
	379	if (!di->priv) {
	380	sr_err("Driver was not initialized.");
	381	return SR_ERR;
	382	}
	383
	384	devc = sdi->priv;
	385	usb = sdi->conn;
	386	devc->cb_data = cb_data;
	387
	388	/* Send header packet to the session bus. */
	389	std_session_send_df_header(cb_data, LOG_PREFIX);
	390
	391	usb_source_add(sdi->session, drvc->sr_ctx, 100,
	392	handle_events, (void *)sdi);
	393
	394	buf = g_try_malloc(DMM_DATA_SIZE);
	395	transfer = libusb_alloc_transfer(0);
	396	/* Each transfer request gets 100ms to arrive before it's restarted.
	397	* The device only sends 1 transfer/second no matter how many
	398	* times you ask, but we want to keep step with the USB events
	399	* handling above. */
	400	libusb_fill_interrupt_transfer(transfer, usb->devhdl,
	401	VICTOR_ENDPOINT, buf, DMM_DATA_SIZE, receive_transfer,
	402	cb_data, 100);
	403	if ((ret = libusb_submit_transfer(transfer) != 0)) {
	404	sr_err("Unable to submit transfer: %s.", libusb_error_name(ret));
	405	libusb_free_transfer(transfer);
	406	g_free(buf);
	407	return SR_ERR;
	408	}
	409
	410	return SR_OK;
	411	}
	412
	413	static int dev_acquisition_stop(struct sr_dev_inst sdi, void cb_data)
	414	{
	415	(void)cb_data;
	416
	417	if (!di->priv) {
	418	sr_err("Driver was not initialized.");
	419	return SR_ERR;
	420	}
	421
	422	if (sdi->status != SR_ST_ACTIVE) {
	423	sr_err("Device not active, can't stop acquisition.");
	424	return SR_ERR;
	425	}
	426
	427	sdi->status = SR_ST_STOPPING;
	428
	429	return SR_OK;
	430	}
	431
	432	SR_PRIV struct sr_dev_driver victor_dmm_driver_info = {
	433	.name = "victor-dmm",
	434	.longname = "Victor DMMs",
	435	.api_version = 1,
	436	.init = init,
	437	.cleanup = cleanup,
	438	.scan = scan,
	439	.dev_list = dev_list,
	440	.dev_clear = NULL,
	441	.config_get = config_get,
	442	.config_set = config_set,
	443	.config_list = config_list,
	444	.dev_open = dev_open,
	445	.dev_close = dev_close,
	446	.dev_acquisition_start = dev_acquisition_start,
	447	.dev_acquisition_stop = dev_acquisition_stop,
	448	.priv = NULL,
	449	};