[libsigrok.git] / src / hardware / lascar-el-usb / 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 <config.h>
#include <glib.h>
#include <libusb.h>
#include <libsigrok/libsigrok.h>
#include "libsigrok-internal.h"
#include "protocol.h"

SR_PRIV struct sr_dev_driver lascar_el_usb_driver_info;

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

static const uint32_t devopts[] = {
	SR_CONF_THERMOMETER,
	SR_CONF_HYGROMETER,
	SR_CONF_CONN | SR_CONF_GET,
	SR_CONF_LIMIT_SAMPLES | SR_CONF_GET | SR_CONF_SET,
	SR_CONF_DATALOG | SR_CONF_GET | SR_CONF_SET,
};

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

static GSList *scan(struct sr_dev_driver *di, GSList *options)
{
	struct drv_context *drvc;
	struct sr_dev_inst *sdi;
	struct sr_usb_dev_inst *usb;
	struct sr_config *src;
	GSList *usb_devices, *devices, *l;
	const char *conn;

	drvc = di->context;

	conn = NULL;
	for (l = options; l; l = l->next) {
		src = l->data;
		switch (src->key) {
		case SR_CONF_CONN:
			conn = g_variant_get_string(src->data, NULL);
			break;
		}
	}
	if (!conn)
		return NULL;

	devices = NULL;
	if ((usb_devices = sr_usb_find(drvc->sr_ctx->libusb_ctx, conn))) {
		/* We have a list of sr_usb_dev_inst matching the connection
		 * string. Wrap them in sr_dev_inst and we're done. */
		for (l = usb_devices; l; l = l->next) {
			usb = l->data;
			if (!(sdi = lascar_scan(usb->bus, usb->address))) {
				/* Not a Lascar EL-USB. */
				g_free(usb);
				continue;
			}
			sdi->inst_type = SR_INST_USB;
			sdi->conn = usb;
			drvc->instances = g_slist_append(drvc->instances, sdi);
			devices = g_slist_append(devices, sdi);
		}
		g_slist_free(usb_devices);
	} else
		g_slist_free_full(usb_devices, g_free);

	return devices;
}

static int dev_open(struct sr_dev_inst *sdi)
{
	struct sr_dev_driver *di = sdi->driver;
	struct drv_context *drvc = di->context;;
	struct sr_usb_dev_inst *usb;
	int ret;

	usb = sdi->conn;

	if (sr_usb_open(drvc->sr_ctx->libusb_ctx, usb) != SR_OK)
		return SR_ERR;

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

	return ret;
}

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

	usb = sdi->conn;

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

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

	return SR_OK;
}

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

	(void)cg;

	devc = sdi->priv;
	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;
	case SR_CONF_DATALOG:
		if (!sdi)
			return SR_ERR_ARG;
		if ((ret = lascar_is_logging(sdi)) == -1)
			return SR_ERR;
		*data = g_variant_new_boolean(ret ? TRUE : FALSE);
		break;
	case SR_CONF_LIMIT_SAMPLES:
		*data = g_variant_new_uint64(devc->limit_samples);
		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;
	int ret;

	(void)cg;

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

	devc = sdi->priv;
	ret = SR_OK;
	switch (key) {
	case SR_CONF_DATALOG:
		if (g_variant_get_boolean(data))
			ret = lascar_start_logging(sdi);
		else
			ret = lascar_stop_logging(sdi);
		break;
	case SR_CONF_LIMIT_SAMPLES:
		devc->limit_samples = g_variant_get_uint64(data);
		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 LIBUSB_CALL mark_xfer(struct libusb_transfer *xfer)
{

	if (xfer->status == LIBUSB_TRANSFER_COMPLETED)
		xfer->user_data = GINT_TO_POINTER(1);
	else
		xfer->user_data = GINT_TO_POINTER(-1);

}

/* The Lascar software, in its infinite ignorance, reads a set of four
 * bytes from the device config struct and interprets it as a float.
 * That only works because they only use windows, and only on x86. However
 * we may be running on any architecture, any operating system. So we have
 * to convert these four bytes as the Lascar software would on windows/x86,
 * to the local representation of a float.
 * The source format is little-endian, with IEEE 754-2008 BINARY32 encoding. */
static float binary32_le_to_float(unsigned char *buf)
{
	GFloatIEEE754 f;

	f.v_float = 0;
	f.mpn.sign = (buf[3] & 0x80) ? 1 : 0;
	f.mpn.biased_exponent = (buf[3] << 1) | (buf[2] >> 7);
	f.mpn.mantissa = buf[0] | (buf[1] << 8) | ((buf[2] & 0x7f) << 16);

	return f.v_float;
}

static int lascar_proc_config(const struct sr_dev_inst *sdi)
{
	struct dev_context *devc;
	struct sr_usb_dev_inst *usb;
	int dummy, ret;

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

	if (lascar_get_config(usb->devhdl, devc->config, &dummy) != SR_OK)
		return SR_ERR;

	ret = SR_OK;
	switch (devc->profile->logformat) {
	case LOG_TEMP_RH:
		devc->sample_size = 2;
		devc->temp_unit = devc->config[0x2e] | (devc->config[0x2f] << 8);
		if (devc->temp_unit != 0 && devc->temp_unit != 1) {
			sr_dbg("invalid temperature unit %d", devc->temp_unit);
			/* Default to Celsius, we're all adults here. */
			devc->temp_unit = 0;
		} else
			sr_dbg("temperature unit is %s", devc->temp_unit
					? "Fahrenheit" : "Celsius");
		break;
	case LOG_CO:
		devc->sample_size = 2;
		devc->co_high = binary32_le_to_float(devc->config + 0x24);
		devc->co_low = binary32_le_to_float(devc->config + 0x28);
		sr_dbg("EL-USB-CO calibration high %f low %f", devc->co_high,
				devc->co_low);
		break;
	default:
		ret = SR_ERR_ARG;
	}
	devc->logged_samples = devc->config[0x1e] | (devc->config[0x1f] << 8);
	sr_dbg("device log contains %d samples.", devc->logged_samples);

	return ret;
}

static int dev_acquisition_start(const struct sr_dev_inst *sdi)
{
	struct sr_dev_driver *di = sdi->driver;
	struct sr_datafeed_packet packet;
	struct sr_datafeed_meta meta;
	struct sr_config *src;
	struct dev_context *devc;
	struct drv_context *drvc;
	struct sr_usb_dev_inst *usb;
	struct libusb_transfer *xfer_in, *xfer_out;
	struct timeval tv;
	uint64_t interval;
	int ret;
	unsigned char cmd[3], resp[4], *buf;

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

	drvc = di->context;
	devc = sdi->priv;
	usb = sdi->conn;

	if (lascar_proc_config(sdi) != SR_OK)
		return SR_ERR;

	sr_dbg("Starting log retrieval.");

	std_session_send_df_header(sdi, LOG_PREFIX);

	interval = (devc->config[0x1c] | (devc->config[0x1d] << 8)) * 1000;
	packet.type = SR_DF_META;
	packet.payload = &meta;
	src = sr_config_new(SR_CONF_SAMPLE_INTERVAL, g_variant_new_uint64(interval));
	meta.config = g_slist_append(NULL, src);
	sr_session_send(sdi, &packet);
	g_free(src);

	if (devc->logged_samples == 0) {
		/* This ensures the frontend knows the session is done. */
		std_session_send_df_end(sdi, LOG_PREFIX);
		return SR_OK;
	}

	if (!(xfer_in = libusb_alloc_transfer(0)) ||
			!(xfer_out = libusb_alloc_transfer(0)))
		return SR_ERR;

	libusb_control_transfer(usb->devhdl, LIBUSB_REQUEST_TYPE_VENDOR,
			0x00, 0xffff, 0x00, NULL, 0, 50);
	libusb_control_transfer(usb->devhdl, LIBUSB_REQUEST_TYPE_VENDOR,
			0x02, 0x0002, 0x00, NULL, 0, 50);
	libusb_control_transfer(usb->devhdl, LIBUSB_REQUEST_TYPE_VENDOR,
			0x02, 0x0001, 0x00, NULL, 0, 50);

	/* Flush input. The F321 requires this. */
	while (libusb_bulk_transfer(usb->devhdl, LASCAR_EP_IN, resp,
			256, &ret, 5) == 0 && ret > 0)
		;

	libusb_fill_bulk_transfer(xfer_in, usb->devhdl, LASCAR_EP_IN,
			resp, sizeof(resp), mark_xfer, 0, BULK_XFER_TIMEOUT);
	if (libusb_submit_transfer(xfer_in) != 0) {
		libusb_free_transfer(xfer_in);
		libusb_free_transfer(xfer_out);
		return SR_ERR;
	}

	cmd[0] = 0x03;
	cmd[1] = 0xff;
	cmd[2] = 0xff;
	libusb_fill_bulk_transfer(xfer_out, usb->devhdl, LASCAR_EP_OUT,
			cmd, 3, mark_xfer, 0, 100);
	if (libusb_submit_transfer(xfer_out) != 0) {
		libusb_free_transfer(xfer_in);
		libusb_free_transfer(xfer_out);
		return SR_ERR;
	}

	tv.tv_sec = 0;
	tv.tv_usec = 0;
	while (!xfer_in->user_data || !xfer_out->user_data) {
		g_usleep(SLEEP_US_LONG);
		libusb_handle_events_timeout(drvc->sr_ctx->libusb_ctx, &tv);
	}
	if (xfer_in->user_data != GINT_TO_POINTER(1) ||
			xfer_out->user_data != GINT_TO_POINTER(1)) {
		sr_dbg("no response to log transfer request");
		libusb_free_transfer(xfer_in);
		libusb_free_transfer(xfer_out);
		return SR_ERR;
	}
	if (xfer_in->actual_length != 3 || xfer_in->buffer[0] != 2) {
		sr_dbg("invalid response to log transfer request");
		libusb_free_transfer(xfer_in);
		libusb_free_transfer(xfer_out);
		return SR_ERR;
	}
	devc->log_size = xfer_in->buffer[1] + (xfer_in->buffer[2] << 8);
	libusb_free_transfer(xfer_out);

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

	buf = g_malloc(4096);
	libusb_fill_bulk_transfer(xfer_in, usb->devhdl, LASCAR_EP_IN,
			buf, 4096, lascar_el_usb_receive_transfer,
			(struct sr_dev_inst *)sdi, 100);
	if ((ret = libusb_submit_transfer(xfer_in) != 0)) {
		sr_err("Unable to submit transfer: %s.", libusb_error_name(ret));
		libusb_free_transfer(xfer_in);
		g_free(buf);
		return SR_ERR;
	}

	return SR_OK;
}

SR_PRIV int dev_acquisition_stop(struct sr_dev_inst *sdi)
{
	if (sdi->status != SR_ST_ACTIVE) {
		sr_err("Device inactive, can't stop acquisition.");
		return SR_ERR;
	}

	sdi->status = SR_ST_STOPPING;
	/* TODO: free ongoing transfers? */

	return SR_OK;
}

SR_PRIV struct sr_dev_driver lascar_el_usb_driver_info = {
	.name = "lascar-el-usb",
	.longname = "Lascar EL-USB",
	.api_version = 1,
	.init = init,
	.cleanup = std_cleanup,
	.scan = scan,
	.dev_list = std_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,
	.context = 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 <config.h>
	21	#include <glib.h>
	22	#include <libusb.h>
	23	#include <libsigrok/libsigrok.h>
	24	#include "libsigrok-internal.h"
	25	#include "protocol.h"
	26
	27	SR_PRIV struct sr_dev_driver lascar_el_usb_driver_info;
	28
	29	static const uint32_t scanopts[] = {
	30	SR_CONF_CONN,
	31	};
	32
	33	static const uint32_t devopts[] = {
	34	SR_CONF_THERMOMETER,
	35	SR_CONF_HYGROMETER,
	36	SR_CONF_CONN \| SR_CONF_GET,
	37	SR_CONF_LIMIT_SAMPLES \| SR_CONF_GET \| SR_CONF_SET,
	38	SR_CONF_DATALOG \| SR_CONF_GET \| SR_CONF_SET,
	39	};
	40
	41	static int init(struct sr_dev_driver di, struct sr_context sr_ctx)
	42	{
	43	return std_init(di, sr_ctx, LOG_PREFIX);
	44	}
	45
	46	static GSList scan(struct sr_dev_driver di, GSList *options)
	47	{
	48	struct drv_context *drvc;
	49	struct sr_dev_inst *sdi;
	50	struct sr_usb_dev_inst *usb;
	51	struct sr_config *src;
	52	GSList usb_devices, devices, *l;
	53	const char *conn;
	54
	55	drvc = di->context;
	56
	57	conn = NULL;
	58	for (l = options; l; l = l->next) {
	59	src = l->data;
	60	switch (src->key) {
	61	case SR_CONF_CONN:
	62	conn = g_variant_get_string(src->data, NULL);
	63	break;
	64	}
	65	}
	66	if (!conn)
	67	return NULL;
	68
	69	devices = NULL;
	70	if ((usb_devices = sr_usb_find(drvc->sr_ctx->libusb_ctx, conn))) {
	71	/* We have a list of sr_usb_dev_inst matching the connection
	72	* string. Wrap them in sr_dev_inst and we're done. */
	73	for (l = usb_devices; l; l = l->next) {
	74	usb = l->data;
	75	if (!(sdi = lascar_scan(usb->bus, usb->address))) {
	76	/* Not a Lascar EL-USB. */
	77	g_free(usb);
	78	continue;
	79	}
	80	sdi->inst_type = SR_INST_USB;
	81	sdi->conn = usb;
	82	drvc->instances = g_slist_append(drvc->instances, sdi);
	83	devices = g_slist_append(devices, sdi);
	84	}
	85	g_slist_free(usb_devices);
	86	} else
	87	g_slist_free_full(usb_devices, g_free);
	88
	89	return devices;
	90	}
	91
	92	static int dev_open(struct sr_dev_inst *sdi)
	93	{
	94	struct sr_dev_driver *di = sdi->driver;
	95	struct drv_context *drvc = di->context;;
	96	struct sr_usb_dev_inst *usb;
	97	int ret;
	98
	99	usb = sdi->conn;
	100
	101	if (sr_usb_open(drvc->sr_ctx->libusb_ctx, usb) != SR_OK)
	102	return SR_ERR;
	103
	104	if ((ret = libusb_claim_interface(usb->devhdl, LASCAR_INTERFACE))) {
	105	sr_err("Failed to claim interface: %s.", libusb_error_name(ret));
	106	return SR_ERR;
	107	}
	108	sdi->status = SR_ST_ACTIVE;
	109
	110	return ret;
	111	}
	112
	113	static int dev_close(struct sr_dev_inst *sdi)
	114	{
	115	struct sr_usb_dev_inst *usb;
	116
	117	usb = sdi->conn;
	118
	119	if (!usb->devhdl)
	120	/* Nothing to do. */
	121	return SR_OK;
	122
	123	libusb_release_interface(usb->devhdl, LASCAR_INTERFACE);
	124	libusb_close(usb->devhdl);
	125	usb->devhdl = NULL;
	126	sdi->status = SR_ST_INACTIVE;
	127
	128	return SR_OK;
	129	}
	130
	131	static int config_get(uint32_t key, GVariant *data, const struct sr_dev_inst sdi,
	132	const struct sr_channel_group *cg)
	133	{
	134	struct dev_context *devc;
	135	struct sr_usb_dev_inst *usb;
	136	int ret;
	137	char str[128];
	138
	139	(void)cg;
	140
	141	devc = sdi->priv;
	142	switch (key) {
	143	case SR_CONF_CONN:
	144	if (!sdi \|\| !sdi->conn)
	145	return SR_ERR_ARG;
	146	usb = sdi->conn;
	147	snprintf(str, 128, "%d.%d", usb->bus, usb->address);
	148	*data = g_variant_new_string(str);
	149	break;
	150	case SR_CONF_DATALOG:
	151	if (!sdi)
	152	return SR_ERR_ARG;
	153	if ((ret = lascar_is_logging(sdi)) == -1)
	154	return SR_ERR;
	155	*data = g_variant_new_boolean(ret ? TRUE : FALSE);
	156	break;
	157	case SR_CONF_LIMIT_SAMPLES:
	158	*data = g_variant_new_uint64(devc->limit_samples);
	159	break;
	160	default:
	161	return SR_ERR_NA;
	162	}
	163
	164	return SR_OK;
	165	}
	166
	167	static int config_set(uint32_t key, GVariant data, const struct sr_dev_inst sdi,
	168	const struct sr_channel_group *cg)
	169	{
	170	struct dev_context *devc;
	171	int ret;
	172
	173	(void)cg;
	174
	175	if (sdi->status != SR_ST_ACTIVE)
	176	return SR_ERR_DEV_CLOSED;
	177
	178	devc = sdi->priv;
	179	ret = SR_OK;
	180	switch (key) {
	181	case SR_CONF_DATALOG:
	182	if (g_variant_get_boolean(data))
	183	ret = lascar_start_logging(sdi);
	184	else
	185	ret = lascar_stop_logging(sdi);
	186	break;
	187	case SR_CONF_LIMIT_SAMPLES:
	188	devc->limit_samples = g_variant_get_uint64(data);
	189	break;
	190	default:
	191	ret = SR_ERR_NA;
	192	}
	193
	194	return ret;
	195	}
	196
	197	static int config_list(uint32_t key, GVariant *data, const struct sr_dev_inst sdi,
	198	const struct sr_channel_group *cg)
	199	{
	200	(void)sdi;
	201	(void)cg;
	202
	203	switch (key) {
	204	case SR_CONF_SCAN_OPTIONS:
	205	*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
	206	scanopts, ARRAY_SIZE(scanopts), sizeof(uint32_t));
	207	break;
	208	case SR_CONF_DEVICE_OPTIONS:
	209	*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
	210	devopts, ARRAY_SIZE(devopts), sizeof(uint32_t));
	211	break;
	212	default:
	213	return SR_ERR_NA;
	214	}
	215
	216	return SR_OK;
	217	}
	218
	219	static void LIBUSB_CALL mark_xfer(struct libusb_transfer *xfer)
	220	{
	221
	222	if (xfer->status == LIBUSB_TRANSFER_COMPLETED)
	223	xfer->user_data = GINT_TO_POINTER(1);
	224	else
	225	xfer->user_data = GINT_TO_POINTER(-1);
	226
	227	}
	228
	229	/* The Lascar software, in its infinite ignorance, reads a set of four
	230	* bytes from the device config struct and interprets it as a float.
	231	* That only works because they only use windows, and only on x86. However
	232	* we may be running on any architecture, any operating system. So we have
	233	* to convert these four bytes as the Lascar software would on windows/x86,
	234	* to the local representation of a float.
	235	* The source format is little-endian, with IEEE 754-2008 BINARY32 encoding. */
	236	static float binary32_le_to_float(unsigned char *buf)
	237	{
	238	GFloatIEEE754 f;
	239
	240	f.v_float = 0;
	241	f.mpn.sign = (buf[3] & 0x80) ? 1 : 0;
	242	f.mpn.biased_exponent = (buf[3] << 1) \| (buf[2] >> 7);
	243	f.mpn.mantissa = buf[0] \| (buf[1] << 8) \| ((buf[2] & 0x7f) << 16);
	244
	245	return f.v_float;
	246	}
	247
	248	static int lascar_proc_config(const struct sr_dev_inst *sdi)
	249	{
	250	struct dev_context *devc;
	251	struct sr_usb_dev_inst *usb;
	252	int dummy, ret;
	253
	254	devc = sdi->priv;
	255	usb = sdi->conn;
	256
	257	if (lascar_get_config(usb->devhdl, devc->config, &dummy) != SR_OK)
	258	return SR_ERR;
	259
	260	ret = SR_OK;
	261	switch (devc->profile->logformat) {
	262	case LOG_TEMP_RH:
	263	devc->sample_size = 2;
	264	devc->temp_unit = devc->config[0x2e] \| (devc->config[0x2f] << 8);
	265	if (devc->temp_unit != 0 && devc->temp_unit != 1) {
	266	sr_dbg("invalid temperature unit %d", devc->temp_unit);
	267	/* Default to Celsius, we're all adults here. */
	268	devc->temp_unit = 0;
	269	} else
	270	sr_dbg("temperature unit is %s", devc->temp_unit
	271	? "Fahrenheit" : "Celsius");
	272	break;
	273	case LOG_CO:
	274	devc->sample_size = 2;
	275	devc->co_high = binary32_le_to_float(devc->config + 0x24);
	276	devc->co_low = binary32_le_to_float(devc->config + 0x28);
	277	sr_dbg("EL-USB-CO calibration high %f low %f", devc->co_high,
	278	devc->co_low);
	279	break;
	280	default:
	281	ret = SR_ERR_ARG;
	282	}
	283	devc->logged_samples = devc->config[0x1e] \| (devc->config[0x1f] << 8);
	284	sr_dbg("device log contains %d samples.", devc->logged_samples);
	285
	286	return ret;
	287	}
	288
	289	static int dev_acquisition_start(const struct sr_dev_inst *sdi)
	290	{
	291	struct sr_dev_driver *di = sdi->driver;
	292	struct sr_datafeed_packet packet;
	293	struct sr_datafeed_meta meta;
	294	struct sr_config *src;
	295	struct dev_context *devc;
	296	struct drv_context *drvc;
	297	struct sr_usb_dev_inst *usb;
	298	struct libusb_transfer xfer_in, xfer_out;
	299	struct timeval tv;
	300	uint64_t interval;
	301	int ret;
	302	unsigned char cmd[3], resp[4], *buf;
	303
	304	if (sdi->status != SR_ST_ACTIVE)
	305	return SR_ERR_DEV_CLOSED;
	306
	307	drvc = di->context;
	308	devc = sdi->priv;
	309	usb = sdi->conn;
	310
	311	if (lascar_proc_config(sdi) != SR_OK)
	312	return SR_ERR;
	313
	314	sr_dbg("Starting log retrieval.");
	315
	316	std_session_send_df_header(sdi, LOG_PREFIX);
	317
	318	interval = (devc->config[0x1c] \| (devc->config[0x1d] << 8)) * 1000;
	319	packet.type = SR_DF_META;
	320	packet.payload = &meta;
	321	src = sr_config_new(SR_CONF_SAMPLE_INTERVAL, g_variant_new_uint64(interval));
	322	meta.config = g_slist_append(NULL, src);
	323	sr_session_send(sdi, &packet);
	324	g_free(src);
	325
	326	if (devc->logged_samples == 0) {
	327	/* This ensures the frontend knows the session is done. */
	328	std_session_send_df_end(sdi, LOG_PREFIX);
	329	return SR_OK;
	330	}
	331
	332	if (!(xfer_in = libusb_alloc_transfer(0)) \|\|
	333	!(xfer_out = libusb_alloc_transfer(0)))
	334	return SR_ERR;
	335
	336	libusb_control_transfer(usb->devhdl, LIBUSB_REQUEST_TYPE_VENDOR,
	337	0x00, 0xffff, 0x00, NULL, 0, 50);
	338	libusb_control_transfer(usb->devhdl, LIBUSB_REQUEST_TYPE_VENDOR,
	339	0x02, 0x0002, 0x00, NULL, 0, 50);
	340	libusb_control_transfer(usb->devhdl, LIBUSB_REQUEST_TYPE_VENDOR,
	341	0x02, 0x0001, 0x00, NULL, 0, 50);
	342
	343	/* Flush input. The F321 requires this. */
	344	while (libusb_bulk_transfer(usb->devhdl, LASCAR_EP_IN, resp,
	345	256, &ret, 5) == 0 && ret > 0)
	346	;
	347
	348	libusb_fill_bulk_transfer(xfer_in, usb->devhdl, LASCAR_EP_IN,
	349	resp, sizeof(resp), mark_xfer, 0, BULK_XFER_TIMEOUT);
	350	if (libusb_submit_transfer(xfer_in) != 0) {
	351	libusb_free_transfer(xfer_in);
	352	libusb_free_transfer(xfer_out);
	353	return SR_ERR;
	354	}
	355
	356	cmd[0] = 0x03;
	357	cmd[1] = 0xff;
	358	cmd[2] = 0xff;
	359	libusb_fill_bulk_transfer(xfer_out, usb->devhdl, LASCAR_EP_OUT,
	360	cmd, 3, mark_xfer, 0, 100);
	361	if (libusb_submit_transfer(xfer_out) != 0) {
	362	libusb_free_transfer(xfer_in);
	363	libusb_free_transfer(xfer_out);
	364	return SR_ERR;
	365	}
	366
	367	tv.tv_sec = 0;
	368	tv.tv_usec = 0;
	369	while (!xfer_in->user_data \|\| !xfer_out->user_data) {
	370	g_usleep(SLEEP_US_LONG);
	371	libusb_handle_events_timeout(drvc->sr_ctx->libusb_ctx, &tv);
	372	}
	373	if (xfer_in->user_data != GINT_TO_POINTER(1) \|\|
	374	xfer_out->user_data != GINT_TO_POINTER(1)) {
	375	sr_dbg("no response to log transfer request");
	376	libusb_free_transfer(xfer_in);
	377	libusb_free_transfer(xfer_out);
	378	return SR_ERR;
	379	}
	380	if (xfer_in->actual_length != 3 \|\| xfer_in->buffer[0] != 2) {
	381	sr_dbg("invalid response to log transfer request");
	382	libusb_free_transfer(xfer_in);
	383	libusb_free_transfer(xfer_out);
	384	return SR_ERR;
	385	}
	386	devc->log_size = xfer_in->buffer[1] + (xfer_in->buffer[2] << 8);
	387	libusb_free_transfer(xfer_out);
	388
	389	usb_source_add(sdi->session, drvc->sr_ctx, 100,
	390	lascar_el_usb_handle_events, (void *)sdi);
	391
	392	buf = g_malloc(4096);
	393	libusb_fill_bulk_transfer(xfer_in, usb->devhdl, LASCAR_EP_IN,
	394	buf, 4096, lascar_el_usb_receive_transfer,
	395	(struct sr_dev_inst *)sdi, 100);
	396	if ((ret = libusb_submit_transfer(xfer_in) != 0)) {
	397	sr_err("Unable to submit transfer: %s.", libusb_error_name(ret));
	398	libusb_free_transfer(xfer_in);
	399	g_free(buf);
	400	return SR_ERR;
	401	}
	402
	403	return SR_OK;
	404	}
	405
	406	SR_PRIV int dev_acquisition_stop(struct sr_dev_inst *sdi)
	407	{
	408	if (sdi->status != SR_ST_ACTIVE) {
	409	sr_err("Device inactive, can't stop acquisition.");
	410	return SR_ERR;
	411	}
	412
	413	sdi->status = SR_ST_STOPPING;
	414	/* TODO: free ongoing transfers? */
	415
	416	return SR_OK;
	417	}
	418
	419	SR_PRIV struct sr_dev_driver lascar_el_usb_driver_info = {
	420	.name = "lascar-el-usb",
	421	.longname = "Lascar EL-USB",
	422	.api_version = 1,
	423	.init = init,
	424	.cleanup = std_cleanup,
	425	.scan = scan,
	426	.dev_list = std_dev_list,
	427	.dev_clear = NULL,
	428	.config_get = config_get,
	429	.config_set = config_set,
	430	.config_list = config_list,
	431	.dev_open = dev_open,
	432	.dev_close = dev_close,
	433	.dev_acquisition_start = dev_acquisition_start,
	434	.dev_acquisition_stop = dev_acquisition_stop,
	435	.context = NULL,
	436	};