[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(sr_ctx, di, 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;
	struct sr_usb_dev_inst *usb;
	int ret;

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

	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_dev_driver *di = sdi->driver;
	struct sr_usb_dev_inst *usb;

	if (!di->context) {
		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, 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 sr_dev_driver *di = sdi->driver;
	struct dev_context *devc;
	int ret;

	(void)cg;

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

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

	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;

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

	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)
{
	struct sr_dev_driver *di = sdi->driver;

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

	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(sr_ctx, di, 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;
	96	struct sr_usb_dev_inst *usb;
	97	int ret;
	98
	99	if (!(drvc = di->context)) {
	100	sr_err("Driver was not initialized.");
	101	return SR_ERR;
	102	}
	103
	104	usb = sdi->conn;
	105
	106	if (sr_usb_open(drvc->sr_ctx->libusb_ctx, usb) != SR_OK)
	107	return SR_ERR;
	108
	109	if ((ret = libusb_claim_interface(usb->devhdl, LASCAR_INTERFACE))) {
	110	sr_err("Failed to claim interface: %s.", libusb_error_name(ret));
	111	return SR_ERR;
	112	}
	113	sdi->status = SR_ST_ACTIVE;
	114
	115	return ret;
	116	}
	117
	118	static int dev_close(struct sr_dev_inst *sdi)
	119	{
	120	struct sr_dev_driver *di = sdi->driver;
	121	struct sr_usb_dev_inst *usb;
	122
	123	if (!di->context) {
	124	sr_err("Driver was not initialized.");
	125	return SR_ERR;
	126	}
	127
	128	usb = sdi->conn;
	129
	130	if (!usb->devhdl)
	131	/* Nothing to do. */
	132	return SR_OK;
	133
	134	libusb_release_interface(usb->devhdl, LASCAR_INTERFACE);
	135	libusb_close(usb->devhdl);
	136	usb->devhdl = NULL;
	137	sdi->status = SR_ST_INACTIVE;
	138
	139	return SR_OK;
	140	}
	141
	142	static int config_get(uint32_t key, GVariant *data, const struct sr_dev_inst sdi,
	143	const struct sr_channel_group *cg)
	144	{
	145	struct dev_context *devc;
	146	struct sr_usb_dev_inst *usb;
	147	int ret;
	148	char str[128];
	149
	150	(void)cg;
	151
	152	devc = sdi->priv;
	153	switch (key) {
	154	case SR_CONF_CONN:
	155	if (!sdi \|\| !sdi->conn)
	156	return SR_ERR_ARG;
	157	usb = sdi->conn;
	158	snprintf(str, 128, "%d.%d", usb->bus, usb->address);
	159	*data = g_variant_new_string(str);
	160	break;
	161	case SR_CONF_DATALOG:
	162	if (!sdi)
	163	return SR_ERR_ARG;
	164	if ((ret = lascar_is_logging(sdi)) == -1)
	165	return SR_ERR;
	166	*data = g_variant_new_boolean(ret ? TRUE : FALSE);
	167	break;
	168	case SR_CONF_LIMIT_SAMPLES:
	169	*data = g_variant_new_uint64(devc->limit_samples);
	170	break;
	171	default:
	172	return SR_ERR_NA;
	173	}
	174
	175	return SR_OK;
	176	}
	177
	178	static int config_set(uint32_t key, GVariant data, const struct sr_dev_inst sdi,
	179	const struct sr_channel_group *cg)
	180	{
	181	struct sr_dev_driver *di = sdi->driver;
	182	struct dev_context *devc;
	183	int ret;
	184
	185	(void)cg;
	186
	187	if (sdi->status != SR_ST_ACTIVE)
	188	return SR_ERR_DEV_CLOSED;
	189
	190	if (!di->context) {
	191	sr_err("Driver was not initialized.");
	192	return SR_ERR;
	193	}
	194
	195	devc = sdi->priv;
	196	ret = SR_OK;
	197	switch (key) {
	198	case SR_CONF_DATALOG:
	199	if (g_variant_get_boolean(data))
	200	ret = lascar_start_logging(sdi);
	201	else
	202	ret = lascar_stop_logging(sdi);
	203	break;
	204	case SR_CONF_LIMIT_SAMPLES:
	205	devc->limit_samples = g_variant_get_uint64(data);
	206	break;
	207	default:
	208	ret = SR_ERR_NA;
	209	}
	210
	211	return ret;
	212	}
	213
	214	static int config_list(uint32_t key, GVariant *data, const struct sr_dev_inst sdi,
	215	const struct sr_channel_group *cg)
	216	{
	217	(void)sdi;
	218	(void)cg;
	219
	220	switch (key) {
	221	case SR_CONF_SCAN_OPTIONS:
	222	*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
	223	scanopts, ARRAY_SIZE(scanopts), sizeof(uint32_t));
	224	break;
	225	case SR_CONF_DEVICE_OPTIONS:
	226	*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
	227	devopts, ARRAY_SIZE(devopts), sizeof(uint32_t));
	228	break;
	229	default:
	230	return SR_ERR_NA;
	231	}
	232
	233	return SR_OK;
	234	}
	235
	236	static void LIBUSB_CALL mark_xfer(struct libusb_transfer *xfer)
	237	{
	238
	239	if (xfer->status == LIBUSB_TRANSFER_COMPLETED)
	240	xfer->user_data = GINT_TO_POINTER(1);
	241	else
	242	xfer->user_data = GINT_TO_POINTER(-1);
	243
	244	}
	245
	246	/* The Lascar software, in its infinite ignorance, reads a set of four
	247	* bytes from the device config struct and interprets it as a float.
	248	* That only works because they only use windows, and only on x86. However
	249	* we may be running on any architecture, any operating system. So we have
	250	* to convert these four bytes as the Lascar software would on windows/x86,
	251	* to the local representation of a float.
	252	* The source format is little-endian, with IEEE 754-2008 BINARY32 encoding. */
	253	static float binary32_le_to_float(unsigned char *buf)
	254	{
	255	GFloatIEEE754 f;
	256
	257	f.v_float = 0;
	258	f.mpn.sign = (buf[3] & 0x80) ? 1 : 0;
	259	f.mpn.biased_exponent = (buf[3] << 1) \| (buf[2] >> 7);
	260	f.mpn.mantissa = buf[0] \| (buf[1] << 8) \| ((buf[2] & 0x7f) << 16);
	261
	262	return f.v_float;
	263	}
	264
	265	static int lascar_proc_config(const struct sr_dev_inst *sdi)
	266	{
	267	struct dev_context *devc;
	268	struct sr_usb_dev_inst *usb;
	269	int dummy, ret;
	270
	271	devc = sdi->priv;
	272	usb = sdi->conn;
	273
	274	if (lascar_get_config(usb->devhdl, devc->config, &dummy) != SR_OK)
	275	return SR_ERR;
	276
	277	ret = SR_OK;
	278	switch (devc->profile->logformat) {
	279	case LOG_TEMP_RH:
	280	devc->sample_size = 2;
	281	devc->temp_unit = devc->config[0x2e] \| (devc->config[0x2f] << 8);
	282	if (devc->temp_unit != 0 && devc->temp_unit != 1) {
	283	sr_dbg("invalid temperature unit %d", devc->temp_unit);
	284	/* Default to Celsius, we're all adults here. */
	285	devc->temp_unit = 0;
	286	} else
	287	sr_dbg("temperature unit is %s", devc->temp_unit
	288	? "Fahrenheit" : "Celsius");
	289	break;
	290	case LOG_CO:
	291	devc->sample_size = 2;
	292	devc->co_high = binary32_le_to_float(devc->config + 0x24);
	293	devc->co_low = binary32_le_to_float(devc->config + 0x28);
	294	sr_dbg("EL-USB-CO calibration high %f low %f", devc->co_high,
	295	devc->co_low);
	296	break;
	297	default:
	298	ret = SR_ERR_ARG;
	299	}
	300	devc->logged_samples = devc->config[0x1e] \| (devc->config[0x1f] << 8);
	301	sr_dbg("device log contains %d samples.", devc->logged_samples);
	302
	303	return ret;
	304	}
	305
	306	static int dev_acquisition_start(const struct sr_dev_inst *sdi)
	307	{
	308	struct sr_dev_driver *di = sdi->driver;
	309	struct sr_datafeed_packet packet;
	310	struct sr_datafeed_meta meta;
	311	struct sr_config *src;
	312	struct dev_context *devc;
	313	struct drv_context *drvc;
	314	struct sr_usb_dev_inst *usb;
	315	struct libusb_transfer xfer_in, xfer_out;
	316	struct timeval tv;
	317	uint64_t interval;
	318	int ret;
	319	unsigned char cmd[3], resp[4], *buf;
	320
	321	if (sdi->status != SR_ST_ACTIVE)
	322	return SR_ERR_DEV_CLOSED;
	323
	324	if (!di->context) {
	325	sr_err("Driver was not initialized.");
	326	return SR_ERR;
	327	}
	328
	329	drvc = di->context;
	330	devc = sdi->priv;
	331	usb = sdi->conn;
	332
	333	if (lascar_proc_config(sdi) != SR_OK)
	334	return SR_ERR;
	335
	336	sr_dbg("Starting log retrieval.");
	337
	338	std_session_send_df_header(sdi, LOG_PREFIX);
	339
	340	interval = (devc->config[0x1c] \| (devc->config[0x1d] << 8)) * 1000;
	341	packet.type = SR_DF_META;
	342	packet.payload = &meta;
	343	src = sr_config_new(SR_CONF_SAMPLE_INTERVAL, g_variant_new_uint64(interval));
	344	meta.config = g_slist_append(NULL, src);
	345	sr_session_send(sdi, &packet);
	346	g_free(src);
	347
	348	if (devc->logged_samples == 0) {
	349	/* This ensures the frontend knows the session is done. */
	350	std_session_send_df_end(sdi, LOG_PREFIX);
	351	return SR_OK;
	352	}
	353
	354	if (!(xfer_in = libusb_alloc_transfer(0)) \|\|
	355	!(xfer_out = libusb_alloc_transfer(0)))
	356	return SR_ERR;
	357
	358	libusb_control_transfer(usb->devhdl, LIBUSB_REQUEST_TYPE_VENDOR,
	359	0x00, 0xffff, 0x00, NULL, 0, 50);
	360	libusb_control_transfer(usb->devhdl, LIBUSB_REQUEST_TYPE_VENDOR,
	361	0x02, 0x0002, 0x00, NULL, 0, 50);
	362	libusb_control_transfer(usb->devhdl, LIBUSB_REQUEST_TYPE_VENDOR,
	363	0x02, 0x0001, 0x00, NULL, 0, 50);
	364
	365	/* Flush input. The F321 requires this. */
	366	while (libusb_bulk_transfer(usb->devhdl, LASCAR_EP_IN, resp,
	367	256, &ret, 5) == 0 && ret > 0)
	368	;
	369
	370	libusb_fill_bulk_transfer(xfer_in, usb->devhdl, LASCAR_EP_IN,
	371	resp, sizeof(resp), mark_xfer, 0, BULK_XFER_TIMEOUT);
	372	if (libusb_submit_transfer(xfer_in) != 0) {
	373	libusb_free_transfer(xfer_in);
	374	libusb_free_transfer(xfer_out);
	375	return SR_ERR;
	376	}
	377
	378	cmd[0] = 0x03;
	379	cmd[1] = 0xff;
	380	cmd[2] = 0xff;
	381	libusb_fill_bulk_transfer(xfer_out, usb->devhdl, LASCAR_EP_OUT,
	382	cmd, 3, mark_xfer, 0, 100);
	383	if (libusb_submit_transfer(xfer_out) != 0) {
	384	libusb_free_transfer(xfer_in);
	385	libusb_free_transfer(xfer_out);
	386	return SR_ERR;
	387	}
	388
	389	tv.tv_sec = 0;
	390	tv.tv_usec = 0;
	391	while (!xfer_in->user_data \|\| !xfer_out->user_data) {
	392	g_usleep(SLEEP_US_LONG);
	393	libusb_handle_events_timeout(drvc->sr_ctx->libusb_ctx, &tv);
	394	}
	395	if (xfer_in->user_data != GINT_TO_POINTER(1) \|\|
	396	xfer_out->user_data != GINT_TO_POINTER(1)) {
	397	sr_dbg("no response to log transfer request");
	398	libusb_free_transfer(xfer_in);
	399	libusb_free_transfer(xfer_out);
	400	return SR_ERR;
	401	}
	402	if (xfer_in->actual_length != 3 \|\| xfer_in->buffer[0] != 2) {
	403	sr_dbg("invalid response to log transfer request");
	404	libusb_free_transfer(xfer_in);
	405	libusb_free_transfer(xfer_out);
	406	return SR_ERR;
	407	}
	408	devc->log_size = xfer_in->buffer[1] + (xfer_in->buffer[2] << 8);
	409	libusb_free_transfer(xfer_out);
	410
	411	usb_source_add(sdi->session, drvc->sr_ctx, 100,
	412	lascar_el_usb_handle_events, (void *)sdi);
	413
	414	buf = g_malloc(4096);
	415	libusb_fill_bulk_transfer(xfer_in, usb->devhdl, LASCAR_EP_IN,
	416	buf, 4096, lascar_el_usb_receive_transfer,
	417	(struct sr_dev_inst *)sdi, 100);
	418	if ((ret = libusb_submit_transfer(xfer_in) != 0)) {
	419	sr_err("Unable to submit transfer: %s.", libusb_error_name(ret));
	420	libusb_free_transfer(xfer_in);
	421	g_free(buf);
	422	return SR_ERR;
	423	}
	424
	425	return SR_OK;
	426	}
	427
	428	SR_PRIV int dev_acquisition_stop(struct sr_dev_inst *sdi)
	429	{
	430	struct sr_dev_driver *di = sdi->driver;
	431
	432	if (!di->context) {
	433	sr_err("Driver was not initialized.");
	434	return SR_ERR;
	435	}
	436
	437	if (sdi->status != SR_ST_ACTIVE) {
	438	sr_err("Device inactive, can't stop acquisition.");
	439	return SR_ERR;
	440	}
	441
	442	sdi->status = SR_ST_STOPPING;
	443	/* TODO: free ongoing transfers? */
	444
	445	return SR_OK;
	446	}
	447
	448	SR_PRIV struct sr_dev_driver lascar_el_usb_driver_info = {
	449	.name = "lascar-el-usb",
	450	.longname = "Lascar EL-USB",
	451	.api_version = 1,
	452	.init = init,
	453	.cleanup = std_cleanup,
	454	.scan = scan,
	455	.dev_list = std_dev_list,
	456	.dev_clear = NULL,
	457	.config_get = config_get,
	458	.config_set = config_set,
	459	.config_list = config_list,
	460	.dev_open = dev_open,
	461	.dev_close = dev_close,
	462	.dev_acquisition_start = dev_acquisition_start,
	463	.dev_acquisition_stop = dev_acquisition_stop,
	464	.context = NULL,
	465	};