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

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

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, i;
	char connection_id[64];

	(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;

		usb_get_port_path(devlist[i], connection_id, sizeof(connection_id));

		sdi = sr_dev_inst_new();
		sdi->status = SR_ST_INACTIVE;
		sdi->vendor = g_strdup(VICTOR_VENDOR);
		sdi->driver = di;
		sdi->connection_id = g_strdup(connection_id);

		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;
	char connection_id[64];

	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++) {
		usb_get_port_path(devlist[i], connection_id, sizeof(connection_id));
		if (strcmp(sdi->connection_id, connection_id))
			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:
		if (!sdi)
			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
					drvopts, ARRAY_SIZE(drvopts), sizeof(uint32_t));
		else
			*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 drvopts[] = {
	39	SR_CONF_MULTIMETER,
	40	};
	41	static const uint32_t scanopts[] = {
	42	SR_CONF_CONN,
	43	};
	44
	45	static const uint32_t devopts[] = {
	46	SR_CONF_CONTINUOUS,
	47	SR_CONF_LIMIT_SAMPLES \| SR_CONF_SET,
	48	SR_CONF_LIMIT_MSEC \| SR_CONF_SET,
	49	SR_CONF_CONN \| SR_CONF_GET,
	50	};
	51
	52	static int init(struct sr_context *sr_ctx)
	53	{
	54	return std_init(sr_ctx, di, LOG_PREFIX);
	55	}
	56
	57	static GSList scan(GSList options)
	58	{
	59	struct drv_context *drvc;
	60	struct dev_context *devc;
	61	struct sr_dev_inst *sdi;
	62	struct sr_channel *ch;
	63	struct libusb_device_descriptor des;
	64	libusb_device **devlist;
	65	GSList *devices;
	66	int ret, i;
	67	char connection_id[64];
	68
	69	(void)options;
	70
	71	drvc = di->priv;
	72
	73	devices = NULL;
	74	libusb_get_device_list(drvc->sr_ctx->libusb_ctx, &devlist);
	75	for (i = 0; devlist[i]; i++) {
	76	if ((ret = libusb_get_device_descriptor(devlist[i], &des)) != 0) {
	77	sr_warn("Failed to get device descriptor: %s",
	78	libusb_error_name(ret));
	79	continue;
	80	}
	81
	82	if (des.idVendor != VICTOR_VID \|\| des.idProduct != VICTOR_PID)
	83	continue;
	84
	85	usb_get_port_path(devlist[i], connection_id, sizeof(connection_id));
	86
	87	sdi = sr_dev_inst_new();
	88	sdi->status = SR_ST_INACTIVE;
	89	sdi->vendor = g_strdup(VICTOR_VENDOR);
	90	sdi->driver = di;
	91	sdi->connection_id = g_strdup(connection_id);
	92
	93	if (!(devc = g_try_malloc0(sizeof(struct dev_context))))
	94	return NULL;
	95	sdi->priv = devc;
	96
	97	if (!(ch = sr_channel_new(0, SR_CHANNEL_ANALOG, TRUE, "P1")))
	98	return NULL;
	99	sdi->channels = g_slist_append(NULL, ch);
	100
	101	if (!(sdi->conn = sr_usb_dev_inst_new(libusb_get_bus_number(devlist[i]),
	102	libusb_get_device_address(devlist[i]), NULL)))
	103	return NULL;
	104	sdi->inst_type = SR_INST_USB;
	105
	106	drvc->instances = g_slist_append(drvc->instances, sdi);
	107	devices = g_slist_append(devices, sdi);
	108	}
	109	libusb_free_device_list(devlist, 1);
	110
	111	return devices;
	112	}
	113
	114	static GSList *dev_list(void)
	115	{
	116	return ((struct drv_context *)(di->priv))->instances;
	117	}
	118
	119	static int dev_open(struct sr_dev_inst *sdi)
	120	{
	121	struct drv_context *drvc = di->priv;
	122	struct sr_usb_dev_inst *usb;
	123	libusb_device **devlist;
	124	int ret, i;
	125	char connection_id[64];
	126
	127	if (!di->priv) {
	128	sr_err("Driver was not initialized.");
	129	return SR_ERR;
	130	}
	131
	132	usb = sdi->conn;
	133
	134	libusb_get_device_list(drvc->sr_ctx->libusb_ctx, &devlist);
	135	for (i = 0; devlist[i]; i++) {
	136	usb_get_port_path(devlist[i], connection_id, sizeof(connection_id));
	137	if (strcmp(sdi->connection_id, connection_id))
	138	continue;
	139	if ((ret = libusb_open(devlist[i], &usb->devhdl))) {
	140	sr_err("Failed to open device: %s.", libusb_error_name(ret));
	141	return SR_ERR;
	142	}
	143	break;
	144	}
	145	libusb_free_device_list(devlist, 1);
	146	if (!devlist[i]) {
	147	sr_err("Device not found.");
	148	return SR_ERR;
	149	}
	150
	151	/* The device reports as HID class, so the kernel would have
	152	* claimed it. */
	153	if (libusb_kernel_driver_active(usb->devhdl, 0) == 1) {
	154	if ((ret = libusb_detach_kernel_driver(usb->devhdl, 0)) < 0) {
	155	sr_err("Failed to detach kernel driver: %s.",
	156	libusb_error_name(ret));
	157	return SR_ERR;
	158	}
	159	}
	160
	161	if ((ret = libusb_claim_interface(usb->devhdl,
	162	VICTOR_INTERFACE))) {
	163	sr_err("Failed to claim interface: %s.", libusb_error_name(ret));
	164	return SR_ERR;
	165	}
	166	sdi->status = SR_ST_ACTIVE;
	167
	168	return SR_OK;
	169	}
	170
	171	static int dev_close(struct sr_dev_inst *sdi)
	172	{
	173	struct sr_usb_dev_inst *usb;
	174
	175	if (!di->priv) {
	176	sr_err("Driver was not initialized.");
	177	return SR_ERR;
	178	}
	179
	180	usb = sdi->conn;
	181
	182	if (!usb->devhdl)
	183	/* Nothing to do. */
	184	return SR_OK;
	185
	186	libusb_release_interface(usb->devhdl, VICTOR_INTERFACE);
	187	libusb_close(usb->devhdl);
	188	usb->devhdl = NULL;
	189	sdi->status = SR_ST_INACTIVE;
	190
	191	return SR_OK;
	192	}
	193
	194	static int cleanup(void)
	195	{
	196	int ret;
	197	struct drv_context *drvc;
	198
	199	if (!(drvc = di->priv))
	200	/* Can get called on an unused driver, doesn't matter. */
	201	return SR_OK;
	202
	203
	204	ret = std_dev_clear(di, NULL);
	205	g_free(drvc);
	206	di->priv = NULL;
	207
	208	return ret;
	209	}
	210
	211	static int config_get(uint32_t key, GVariant *data, const struct sr_dev_inst sdi,
	212	const struct sr_channel_group *cg)
	213	{
	214	struct sr_usb_dev_inst *usb;
	215	char str[128];
	216
	217	(void)cg;
	218
	219	switch (key) {
	220	case SR_CONF_CONN:
	221	if (!sdi \|\| !sdi->conn)
	222	return SR_ERR_ARG;
	223	usb = sdi->conn;
	224	snprintf(str, 128, "%d.%d", usb->bus, usb->address);
	225	*data = g_variant_new_string(str);
	226	break;
	227	default:
	228	return SR_ERR_NA;
	229	}
	230
	231	return SR_OK;
	232	}
	233
	234	static int config_set(uint32_t key, GVariant data, const struct sr_dev_inst sdi,
	235	const struct sr_channel_group *cg)
	236	{
	237	struct dev_context *devc;
	238	gint64 now;
	239	int ret;
	240
	241	(void)cg;
	242
	243	if (sdi->status != SR_ST_ACTIVE)
	244	return SR_ERR_DEV_CLOSED;
	245
	246	if (!di->priv) {
	247	sr_err("Driver was not initialized.");
	248	return SR_ERR;
	249	}
	250
	251	devc = sdi->priv;
	252	ret = SR_OK;
	253	switch (key) {
	254	case SR_CONF_LIMIT_MSEC:
	255	devc->limit_msec = g_variant_get_uint64(data);
	256	now = g_get_monotonic_time() / 1000;
	257	devc->end_time = now + devc->limit_msec;
	258	sr_dbg("Setting time limit to %" PRIu64 "ms.",
	259	devc->limit_msec);
	260	break;
	261	case SR_CONF_LIMIT_SAMPLES:
	262	devc->limit_samples = g_variant_get_uint64(data);
	263	sr_dbg("Setting sample limit to %" PRIu64 ".",
	264	devc->limit_samples);
	265	break;
	266	default:
	267	ret = SR_ERR_NA;
	268	}
	269
	270	return ret;
	271	}
	272
	273	static int config_list(uint32_t key, GVariant *data, const struct sr_dev_inst sdi,
	274	const struct sr_channel_group *cg)
	275	{
	276	(void)sdi;
	277	(void)cg;
	278
	279	switch (key) {
	280	case SR_CONF_SCAN_OPTIONS:
	281	*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
	282	scanopts, ARRAY_SIZE(scanopts), sizeof(uint32_t));
	283	break;
	284	case SR_CONF_DEVICE_OPTIONS:
	285	if (!sdi)
	286	*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
	287	drvopts, ARRAY_SIZE(drvopts), sizeof(uint32_t));
	288	else
	289	*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
	290	devopts, ARRAY_SIZE(devopts), sizeof(uint32_t));
	291	break;
	292	default:
	293	return SR_ERR_NA;
	294	}
	295
	296	return SR_OK;
	297	}
	298
	299	static void receive_transfer(struct libusb_transfer *transfer)
	300	{
	301	struct dev_context *devc;
	302	struct sr_dev_inst *sdi;
	303	int ret;
	304
	305	sdi = transfer->user_data;
	306	devc = sdi->priv;
	307	if (transfer->status == LIBUSB_TRANSFER_NO_DEVICE) {
	308	/* USB device was unplugged. */
	309	dev_acquisition_stop(sdi, sdi);
	310	} else if (transfer->status == LIBUSB_TRANSFER_COMPLETED) {
	311	sr_dbg("Got %d-byte packet.", transfer->actual_length);
	312	if (transfer->actual_length == DMM_DATA_SIZE) {
	313	victor_dmm_receive_data(sdi, transfer->buffer);
	314	if (devc->limit_samples) {
	315	if (devc->num_samples >= devc->limit_samples)
	316	dev_acquisition_stop(sdi, sdi);
	317	}
	318	}
	319	}
	320	/* Anything else is either an error or a timeout, which is fine:
	321	* we were just going to send another transfer request anyway. */
	322
	323	if (sdi->status == SR_ST_ACTIVE) {
	324	/* Send the same request again. */
	325	if ((ret = libusb_submit_transfer(transfer) != 0)) {
	326	sr_err("Unable to resubmit transfer: %s.",
	327	libusb_error_name(ret));
	328	g_free(transfer->buffer);
	329	libusb_free_transfer(transfer);
	330	dev_acquisition_stop(sdi, sdi);
	331	}
	332	} else {
	333	/* This was the last transfer we're going to receive, so
	334	* clean up now. */
	335	g_free(transfer->buffer);
	336	libusb_free_transfer(transfer);
	337	}
	338	}
	339
	340	static int handle_events(int fd, int revents, void *cb_data)
	341	{
	342	struct dev_context *devc;
	343	struct drv_context *drvc = di->priv;
	344	struct sr_datafeed_packet packet;
	345	struct sr_dev_inst *sdi;
	346	struct timeval tv;
	347	gint64 now;
	348
	349	(void)fd;
	350	(void)revents;
	351
	352	sdi = cb_data;
	353	devc = sdi->priv;
	354
	355	if (devc->limit_msec) {
	356	now = g_get_monotonic_time() / 1000;
	357	if (now > devc->end_time)
	358	dev_acquisition_stop(sdi, sdi);
	359	}
	360
	361	if (sdi->status == SR_ST_STOPPING) {
	362	usb_source_remove(sdi->session, drvc->sr_ctx);
	363
	364	dev_close(sdi);
	365
	366	packet.type = SR_DF_END;
	367	sr_session_send(cb_data, &packet);
	368	}
	369
	370	memset(&tv, 0, sizeof(struct timeval));
	371	libusb_handle_events_timeout_completed(drvc->sr_ctx->libusb_ctx, &tv,
	372	NULL);
	373
	374	return TRUE;
	375	}
	376
	377	static int dev_acquisition_start(const struct sr_dev_inst sdi, void cb_data)
	378	{
	379	struct dev_context *devc;
	380	struct drv_context *drvc = di->priv;
	381	struct sr_usb_dev_inst *usb;
	382	struct libusb_transfer *transfer;
	383	int ret;
	384	unsigned char *buf;
	385
	386	if (sdi->status != SR_ST_ACTIVE)
	387	return SR_ERR_DEV_CLOSED;
	388
	389	if (!di->priv) {
	390	sr_err("Driver was not initialized.");
	391	return SR_ERR;
	392	}
	393
	394	devc = sdi->priv;
	395	usb = sdi->conn;
	396	devc->cb_data = cb_data;
	397
	398	/* Send header packet to the session bus. */
	399	std_session_send_df_header(cb_data, LOG_PREFIX);
	400
	401	usb_source_add(sdi->session, drvc->sr_ctx, 100,
	402	handle_events, (void *)sdi);
	403
	404	buf = g_try_malloc(DMM_DATA_SIZE);
	405	transfer = libusb_alloc_transfer(0);
	406	/* Each transfer request gets 100ms to arrive before it's restarted.
	407	* The device only sends 1 transfer/second no matter how many
	408	* times you ask, but we want to keep step with the USB events
	409	* handling above. */
	410	libusb_fill_interrupt_transfer(transfer, usb->devhdl,
	411	VICTOR_ENDPOINT, buf, DMM_DATA_SIZE, receive_transfer,
	412	cb_data, 100);
	413	if ((ret = libusb_submit_transfer(transfer) != 0)) {
	414	sr_err("Unable to submit transfer: %s.", libusb_error_name(ret));
	415	libusb_free_transfer(transfer);
	416	g_free(buf);
	417	return SR_ERR;
	418	}
	419
	420	return SR_OK;
	421	}
	422
	423	static int dev_acquisition_stop(struct sr_dev_inst sdi, void cb_data)
	424	{
	425	(void)cb_data;
	426
	427	if (!di->priv) {
	428	sr_err("Driver was not initialized.");
	429	return SR_ERR;
	430	}
	431
	432	if (sdi->status != SR_ST_ACTIVE) {
	433	sr_err("Device not active, can't stop acquisition.");
	434	return SR_ERR;
	435	}
	436
	437	sdi->status = SR_ST_STOPPING;
	438
	439	return SR_OK;
	440	}
	441
	442	SR_PRIV struct sr_dev_driver victor_dmm_driver_info = {
	443	.name = "victor-dmm",
	444	.longname = "Victor DMMs",
	445	.api_version = 1,
	446	.init = init,
	447	.cleanup = cleanup,
	448	.scan = scan,
	449	.dev_list = dev_list,
	450	.dev_clear = NULL,
	451	.config_get = config_get,
	452	.config_set = config_set,
	453	.config_list = config_list,
	454	.dev_open = dev_open,
	455	.dev_close = dev_close,
	456	.dev_acquisition_start = dev_acquisition_start,
	457	.dev_acquisition_stop = dev_acquisition_stop,
	458	.priv = NULL,
	459	};