[libsigrok.git] / src / hardware / uni-t-dmm / protocol.c

/*
 * This file is part of the libsigrok project.
 *
 * Copyright (C) 2012-2013 Uwe Hermann <uwe@hermann-uwe.de>
 *
 * 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 2 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, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 */

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

/*
 * Driver for various UNI-T multimeters (and rebranded ones).
 *
 * Most UNI-T DMMs can be used with two (three) different PC interface cables:
 *  - The UT-D04 USB/HID cable, old version with Hoitek HE2325U chip.
 *  - The UT-D04 USB/HID cable, new version with WCH CH9325 chip.
 *  - The UT-D02 RS232 cable.
 *
 * This driver is meant to support all USB/HID cables, and various DMMs that
 * can be attached to a PC via these cables. Currently only the UT-D04 cable
 * (new version) is supported/tested.
 * The UT-D02 RS232 cable is handled by the 'serial-dmm' driver.
 *
 * The data for one DMM packet (e.g. 14 bytes if the respective DMM uses a
 * Fortune Semiconductor FS9922-DMM4 chip) is spread across multiple
 * 8-byte chunks.
 *
 * An 8-byte chunk looks like this:
 *  - Byte 0: 0xfz, where z is the number of actual data bytes in this chunk.
 *  - Bytes 1-7: z data bytes, the rest of the bytes should be ignored.
 *
 * Example:
 *  f0 00 00 00 00 00 00 00 (no data bytes)
 *  f2 55 77 00 00 00 00 00 (2 data bytes, 0x55 and 0x77)
 *  f1 d1 00 00 00 00 00 00 (1 data byte, 0xd1)
 */

static void decode_packet(struct sr_dev_inst *sdi, const uint8_t *buf)
{
	struct dev_context *devc;
	struct dmm_info *dmm;
	struct sr_datafeed_packet packet;
	struct sr_datafeed_analog analog;
	float floatval;
	void *info;
	int ret;

	devc = sdi->priv;
	dmm = (struct dmm_info *)sdi->driver;
	memset(&analog, 0, sizeof(struct sr_datafeed_analog));
	info = g_malloc(dmm->info_size);

	/* Parse the protocol packet. */
	ret = dmm->packet_parse(buf, &floatval, &analog, info);
	if (ret != SR_OK) {
		sr_dbg("Invalid DMM packet, ignoring.");
		g_free(info);
		return;
	}

	/* If this DMM needs additional handling, call the resp. function. */
	if (dmm->dmm_details)
		dmm->dmm_details(&analog, info);

	g_free(info);

	/* Send a sample packet with one analog value. */
	analog.channels = sdi->channels;
	analog.num_samples = 1;
	analog.data = &floatval;
	packet.type = SR_DF_ANALOG;
	packet.payload = &analog;
	sr_session_send(devc->cb_data, &packet);

	/* Increase sample count. */
	devc->num_samples++;
}

static int hid_chip_init(struct sr_dev_inst *sdi, uint16_t baudrate)
{
	int ret;
	uint8_t buf[5];
	struct sr_usb_dev_inst *usb;

	usb = sdi->conn;
	
	/* Detach kernel drivers which grabbed this device (if any). */
	if (libusb_kernel_driver_active(usb->devhdl, 0) == 1) {
		ret = libusb_detach_kernel_driver(usb->devhdl, 0);
		if (ret < 0) {
			sr_err("Failed to detach kernel driver: %s.",
			       libusb_error_name(ret));
			return SR_ERR;
		}
		sr_dbg("Successfully detached kernel driver.");
	} else {
		sr_dbg("No need to detach a kernel driver.");
	}

	/* Claim interface 0. */
	if ((ret = libusb_claim_interface(usb->devhdl, 0)) < 0) {
		sr_err("Failed to claim interface 0: %s.",
		       libusb_error_name(ret));
		return SR_ERR;
	}
	sr_dbg("Successfully claimed interface 0.");

	/* Set data for the HID feature report (e.g. baudrate). */
	buf[0] = baudrate & 0xff;        /* Baudrate, LSB */
	buf[1] = (baudrate >> 8) & 0xff; /* Baudrate, MSB */
	buf[2] = 0x00;                   /* Unknown/unused (?) */
	buf[3] = 0x00;                   /* Unknown/unused (?) */
	buf[4] = 0x03;                   /* Unknown, always 0x03. */

	/* Send HID feature report to setup the baudrate/chip. */
	sr_dbg("Sending initial HID feature report.");
	sr_spew("HID init = 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x (%d baud)",
		buf[0], buf[1], buf[2], buf[3], buf[4], baudrate);
	ret = libusb_control_transfer(
		usb->devhdl, /* libusb device handle */
		LIBUSB_REQUEST_TYPE_CLASS |
		LIBUSB_RECIPIENT_INTERFACE |
		LIBUSB_ENDPOINT_OUT,
		9, /* bRequest: HID set_report */
		0x300, /* wValue: HID feature, report number 0 */
		0, /* wIndex: interface 0 */
		(unsigned char *)&buf, /* payload buffer */
		5, /* wLength: 5 bytes payload */
		1000 /* timeout (ms) */);

	if (ret < 0) {
		sr_err("HID feature report error: %s.", libusb_error_name(ret));
		return SR_ERR;
	}

	if (ret != 5) {
		/* TODO: Handle better by also sending the remaining bytes. */
		sr_err("Short packet: sent %d/5 bytes.", ret);
		return SR_ERR;
	}

	sr_dbg("Successfully sent initial HID feature report.");

	return SR_OK;
}

static void log_8byte_chunk(const uint8_t *buf)
{
	sr_spew("8-byte chunk: %02x %02x %02x %02x %02x %02x %02x %02x "
		"(%d data bytes)", buf[0], buf[1], buf[2], buf[3],
		buf[4], buf[5], buf[6], buf[7], (buf[0] & 0x0f));
}

static void log_dmm_packet(const uint8_t *buf)
{
	sr_dbg("DMM packet:   %02x %02x %02x %02x %02x %02x %02x"
	       " %02x %02x %02x %02x %02x %02x %02x",
	       buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6],
	       buf[7], buf[8], buf[9], buf[10], buf[11], buf[12], buf[13]);
}

static int get_and_handle_data(struct sr_dev_inst *sdi)
{
	struct dev_context *devc;
	struct dmm_info *dmm;
	uint8_t buf[CHUNK_SIZE], *pbuf;
	int i, ret, len, num_databytes_in_chunk;
	struct sr_usb_dev_inst *usb;

	devc = sdi->priv;
	dmm = (struct dmm_info *)sdi->driver;
	usb = sdi->conn;
	pbuf = devc->protocol_buf;

	/* On the first run, we need to init the HID chip. */
	if (devc->first_run) {
		if ((ret = hid_chip_init(sdi, dmm->baudrate)) != SR_OK) {
			sr_err("HID chip init failed: %d.", ret);
			return SR_ERR;
		}
		memset(pbuf, 0x00, DMM_BUFSIZE);
		devc->first_run = FALSE;
	}

	memset(&buf, 0x00, CHUNK_SIZE);

	/* Get data from EP2 using an interrupt transfer. */
	ret = libusb_interrupt_transfer(
		usb->devhdl, /* libusb device handle */
		LIBUSB_ENDPOINT_IN | 2, /* EP2, IN */
		(unsigned char *)&buf, /* receive buffer */
		CHUNK_SIZE, /* wLength */
		&len, /* actually received byte count */
		1000 /* timeout (ms) */);

	if (ret < 0) {
		sr_err("USB receive error: %s.", libusb_error_name(ret));
		return SR_ERR;
	}

	if (len != CHUNK_SIZE) {
		sr_err("Short packet: received %d/%d bytes.", len, CHUNK_SIZE);
		/* TODO: Print the bytes? */
		return SR_ERR;
	}

	log_8byte_chunk((const uint8_t *)&buf);

	/* If there are no data bytes just return (without error). */
	if (buf[0] == 0xf0)
		return SR_OK;

	devc->bufoffset = 0;

	/*
	 * Append the 1-7 data bytes of this chunk to pbuf.
	 *
	 * Special case:
	 * DMMs with Cyrustek ES51922 chip and UT71x DMMs need serial settings
	 * of 7o1. The WCH CH9325 UART to USB/HID chip used in (some
	 * versions of) the UNI-T UT-D04 cable however, will also send
	 * the parity bit to the host in the 8-byte data chunks. This bit
	 * is encoded in bit 7 of each of the 1-7 data bytes and must thus
	 * be removed in order for the actual protocol parser to work properly.
	 */
	num_databytes_in_chunk = buf[0] & 0x0f;
	for (i = 0; i < num_databytes_in_chunk; i++, devc->buflen++) {
		pbuf[devc->buflen] = buf[1 + i];
		if ((dmm->packet_parse == sr_es519xx_19200_14b_parse) ||
		    (dmm->packet_parse == sr_ut71x_parse)) {
			/* Mask off the parity bit. */
			pbuf[devc->buflen] &= ~(1 << 7);
		}
	}

	/* Now look for packets in that data. */
	while ((devc->buflen - devc->bufoffset) >= dmm->packet_size) {
		if (dmm->packet_valid(pbuf + devc->bufoffset)) {
			log_dmm_packet(pbuf + devc->bufoffset);
			decode_packet(sdi, pbuf + devc->bufoffset);
			devc->bufoffset += dmm->packet_size;
		} else {
			devc->bufoffset++;
		}
	}

	/* Move remaining bytes to beginning of buffer. */
	for (i = 0; i < devc->buflen - devc->bufoffset; i++)
		pbuf[i] = pbuf[devc->bufoffset + i];
	devc->buflen -= devc->bufoffset;

	return SR_OK;
}

SR_PRIV int uni_t_dmm_receive_data(int fd, int revents, void *cb_data)
{
	int ret;
	struct sr_dev_inst *sdi;
	struct dev_context *devc;
	int64_t time_ms;

	(void)fd;
	(void)revents;

	sdi = cb_data;
	devc = sdi->priv;

	if ((ret = get_and_handle_data(sdi)) != SR_OK)
		return FALSE;

	/* Abort acquisition if we acquired enough samples. */
	if (devc->limit_samples && devc->num_samples >= devc->limit_samples) {
		sr_info("Requested number of samples reached.");
		sdi->driver->dev_acquisition_stop(sdi, cb_data);
	}

	if (devc->limit_msec) {
		time_ms = (g_get_monotonic_time() - devc->starttime) / 1000;
		if (time_ms > (int64_t)devc->limit_msec) {
			sr_info("Requested time limit reached.");
			sdi->driver->dev_acquisition_stop(sdi, cb_data);
			return TRUE;
		}
	}

	return TRUE;
}
Commit	Line	Data
79081ec8	1	/*
50985c20	2	* This file is part of the libsigrok project.
79081ec8	3	*
bc653a56	4	* Copyright (C) 2012-2013 Uwe Hermann <uwe@hermann-uwe.de>
79081ec8 UH	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 2 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, write to the Free Software
	18	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	19	*/
	20
	21	#include <string.h>
	22	#include <glib.h>
c1aae900	23	#include <libsigrok/libsigrok.h>
79081ec8 UH	24	#include "libsigrok-internal.h"
	25	#include "protocol.h"
	26
	27	/*
	28	* Driver for various UNI-T multimeters (and rebranded ones).
	29	*
	30	* Most UNI-T DMMs can be used with two (three) different PC interface cables:
	31	* - The UT-D04 USB/HID cable, old version with Hoitek HE2325U chip.
	32	* - The UT-D04 USB/HID cable, new version with WCH CH9325 chip.
c8852687	33	* - The UT-D02 RS232 cable.
79081ec8	34	*
c8852687	35	* This driver is meant to support all USB/HID cables, and various DMMs that
79081ec8	36	* can be attached to a PC via these cables. Currently only the UT-D04 cable
c8852687 UH	37	* (new version) is supported/tested.
c8852687 UH	38	* The UT-D02 RS232 cable is handled by the 'serial-dmm' driver.
79081ec8 UH	39	*
	40	* The data for one DMM packet (e.g. 14 bytes if the respective DMM uses a
	41	* Fortune Semiconductor FS9922-DMM4 chip) is spread across multiple
	42	* 8-byte chunks.
	43	*
	44	* An 8-byte chunk looks like this:
	45	* - Byte 0: 0xfz, where z is the number of actual data bytes in this chunk.
	46	* - Bytes 1-7: z data bytes, the rest of the bytes should be ignored.
	47	*
	48	* Example:
	49	* f0 00 00 00 00 00 00 00 (no data bytes)
	50	* f2 55 77 00 00 00 00 00 (2 data bytes, 0x55 and 0x77)
	51	* f1 d1 00 00 00 00 00 00 (1 data byte, 0xd1)
79081ec8 UH	52	*/
79081ec8 UH	53
f0540611	54	static void decode_packet(struct sr_dev_inst sdi, const uint8_t buf)
79081ec8	55	{
bc653a56	56	struct dev_context *devc;
f0540611	57	struct dmm_info *dmm;
79081ec8 UH	58	struct sr_datafeed_packet packet;
	59	struct sr_datafeed_analog analog;
	60	float floatval;
f0540611	61	void *info;
79081ec8 UH	62	int ret;
79081ec8 UH	63
69e19dd7	64	devc = sdi->priv;
f0540611	65	dmm = (struct dmm_info *)sdi->driver;
79081ec8	66	memset(&analog, 0, sizeof(struct sr_datafeed_analog));
f0540611	67	info = g_malloc(dmm->info_size);
79081ec8 UH	68
79081ec8 UH	69	/* Parse the protocol packet. */
f0540611	70	ret = dmm->packet_parse(buf, &floatval, &analog, info);
fdbcb86d	71	if (ret != SR_OK) {
bc653a56	72	sr_dbg("Invalid DMM packet, ignoring.");
f0540611	73	g_free(info);
79081ec8 UH	74	return;
	75	}
	76
c8852687	77	/* If this DMM needs additional handling, call the resp. function. */
f0540611 ML	78	if (dmm->dmm_details)
	79	dmm->dmm_details(&analog, info);
	80
	81	g_free(info);
c8852687	82
79081ec8	83	/* Send a sample packet with one analog value. */
ba7dd8bb	84	analog.channels = sdi->channels;
79081ec8 UH	85	analog.num_samples = 1;
	86	analog.data = &floatval;
	87	packet.type = SR_DF_ANALOG;
	88	packet.payload = &analog;
	89	sr_session_send(devc->cb_data, &packet);
	90
	91	/* Increase sample count. */
	92	devc->num_samples++;
	93	}
	94
3ece1dff	95	static int hid_chip_init(struct sr_dev_inst *sdi, uint16_t baudrate)
79081ec8 UH	96	{
	97	int ret;
	98	uint8_t buf[5];
3ece1dff	99	struct sr_usb_dev_inst *usb;
79081ec8	100
3ece1dff UH	101	usb = sdi->conn;
3ece1dff UH	102
79081ec8	103	/* Detach kernel drivers which grabbed this device (if any). */
3ece1dff UH	104	if (libusb_kernel_driver_active(usb->devhdl, 0) == 1) {
3ece1dff UH	105	ret = libusb_detach_kernel_driver(usb->devhdl, 0);
79081ec8	106	if (ret < 0) {
d4928d71 PS	107	sr_err("Failed to detach kernel driver: %s.",
d4928d71 PS	108	libusb_error_name(ret));
79081ec8 UH	109	return SR_ERR;
	110	}
	111	sr_dbg("Successfully detached kernel driver.");
	112	} else {
	113	sr_dbg("No need to detach a kernel driver.");
	114	}
	115
	116	/* Claim interface 0. */
3ece1dff	117	if ((ret = libusb_claim_interface(usb->devhdl, 0)) < 0) {
d4928d71 PS	118	sr_err("Failed to claim interface 0: %s.",
d4928d71 PS	119	libusb_error_name(ret));
79081ec8 UH	120	return SR_ERR;
	121	}
	122	sr_dbg("Successfully claimed interface 0.");
	123
bc653a56	124	/* Set data for the HID feature report (e.g. baudrate). */
79081ec8 UH	125	buf[0] = baudrate & 0xff; /* Baudrate, LSB */
	126	buf[1] = (baudrate >> 8) & 0xff; /* Baudrate, MSB */
	127	buf[2] = 0x00; /* Unknown/unused (?) */
	128	buf[3] = 0x00; /* Unknown/unused (?) */
	129	buf[4] = 0x03; /* Unknown, always 0x03. */
	130
	131	/* Send HID feature report to setup the baudrate/chip. */
	132	sr_dbg("Sending initial HID feature report.");
	133	sr_spew("HID init = 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x (%d baud)",
	134	buf[0], buf[1], buf[2], buf[3], buf[4], baudrate);
	135	ret = libusb_control_transfer(
3ece1dff	136	usb->devhdl, /* libusb device handle */
79081ec8 UH	137	LIBUSB_REQUEST_TYPE_CLASS \|
	138	LIBUSB_RECIPIENT_INTERFACE \|
	139	LIBUSB_ENDPOINT_OUT,
	140	9, /* bRequest: HID set_report */
	141	0x300, /* wValue: HID feature, report number 0 */
	142	0, /* wIndex: interface 0 */
	143	(unsigned char )&buf, / payload buffer */
	144	5, /* wLength: 5 bytes payload */
	145	1000 /* timeout (ms) */);
	146
	147	if (ret < 0) {
d4928d71	148	sr_err("HID feature report error: %s.", libusb_error_name(ret));
79081ec8 UH	149	return SR_ERR;
	150	}
	151
	152	if (ret != 5) {
	153	/* TODO: Handle better by also sending the remaining bytes. */
	154	sr_err("Short packet: sent %d/5 bytes.", ret);
	155	return SR_ERR;
	156	}
	157
	158	sr_dbg("Successfully sent initial HID feature report.");
	159
	160	return SR_OK;
	161	}
	162
	163	static void log_8byte_chunk(const uint8_t *buf)
	164	{
	165	sr_spew("8-byte chunk: %02x %02x %02x %02x %02x %02x %02x %02x "
	166	"(%d data bytes)", buf[0], buf[1], buf[2], buf[3],
	167	buf[4], buf[5], buf[6], buf[7], (buf[0] & 0x0f));
	168	}
	169
	170	static void log_dmm_packet(const uint8_t *buf)
	171	{
	172	sr_dbg("DMM packet: %02x %02x %02x %02x %02x %02x %02x"
	173	" %02x %02x %02x %02x %02x %02x %02x",
	174	buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6],
	175	buf[7], buf[8], buf[9], buf[10], buf[11], buf[12], buf[13]);
	176	}
	177
f0540611	178	static int get_and_handle_data(struct sr_dev_inst *sdi)
79081ec8	179	{
79081ec8	180	struct dev_context *devc;
f0540611	181	struct dmm_info *dmm;
bc653a56	182	uint8_t buf[CHUNK_SIZE], *pbuf;
79081ec8	183	int i, ret, len, num_databytes_in_chunk;
3ece1dff	184	struct sr_usb_dev_inst *usb;
79081ec8	185
79081ec8	186	devc = sdi->priv;
f0540611	187	dmm = (struct dmm_info *)sdi->driver;
3ece1dff	188	usb = sdi->conn;
79081ec8 UH	189	pbuf = devc->protocol_buf;
	190
	191	/* On the first run, we need to init the HID chip. */
bc653a56	192	if (devc->first_run) {
f0540611	193	if ((ret = hid_chip_init(sdi, dmm->baudrate)) != SR_OK) {
79081ec8	194	sr_err("HID chip init failed: %d.", ret);
bc653a56	195	return SR_ERR;
79081ec8	196	}
bc653a56 UH	197	memset(pbuf, 0x00, DMM_BUFSIZE);
bc653a56 UH	198	devc->first_run = FALSE;
79081ec8 UH	199	}
	200
	201	memset(&buf, 0x00, CHUNK_SIZE);
	202
	203	/* Get data from EP2 using an interrupt transfer. */
	204	ret = libusb_interrupt_transfer(
3ece1dff	205	usb->devhdl, /* libusb device handle */
79081ec8 UH	206	LIBUSB_ENDPOINT_IN \| 2, /* EP2, IN */
	207	(unsigned char )&buf, / receive buffer */
	208	CHUNK_SIZE, /* wLength */
	209	&len, /* actually received byte count */
	210	1000 /* timeout (ms) */);
	211
	212	if (ret < 0) {
d4928d71	213	sr_err("USB receive error: %s.", libusb_error_name(ret));
bc653a56	214	return SR_ERR;
79081ec8 UH	215	}
	216
	217	if (len != CHUNK_SIZE) {
	218	sr_err("Short packet: received %d/%d bytes.", len, CHUNK_SIZE);
	219	/* TODO: Print the bytes? */
bc653a56	220	return SR_ERR;
79081ec8 UH	221	}
	222
	223	log_8byte_chunk((const uint8_t *)&buf);
	224
bc653a56 UH	225	/* If there are no data bytes just return (without error). */
	226	if (buf[0] == 0xf0)
	227	return SR_OK;
	228
	229	devc->bufoffset = 0;
	230
4d7ddff7 UH	231	/*
	232	* Append the 1-7 data bytes of this chunk to pbuf.
	233	*
	234	* Special case:
8769478c UH	235	* DMMs with Cyrustek ES51922 chip and UT71x DMMs need serial settings
8769478c UH	236	* of 7o1. The WCH CH9325 UART to USB/HID chip used in (some
4d7ddff7 UH	237	* versions of) the UNI-T UT-D04 cable however, will also send
	238	* the parity bit to the host in the 8-byte data chunks. This bit
	239	* is encoded in bit 7 of each of the 1-7 data bytes and must thus
8769478c	240	* be removed in order for the actual protocol parser to work properly.
4d7ddff7	241	*/
bc653a56	242	num_databytes_in_chunk = buf[0] & 0x0f;
4d7ddff7 UH	243	for (i = 0; i < num_databytes_in_chunk; i++, devc->buflen++) {
4d7ddff7 UH	244	pbuf[devc->buflen] = buf[1 + i];
f0540611 ML	245	if ((dmm->packet_parse == sr_es519xx_19200_14b_parse) \|\|
f0540611 ML	246	(dmm->packet_parse == sr_ut71x_parse)) {
8769478c	247	/* Mask off the parity bit. */
4d7ddff7	248	pbuf[devc->buflen] &= ~(1 << 7);
8769478c	249	}
4d7ddff7	250	}
bc653a56 UH	251
bc653a56 UH	252	/* Now look for packets in that data. */
f0540611 ML	253	while ((devc->buflen - devc->bufoffset) >= dmm->packet_size) {
f0540611 ML	254	if (dmm->packet_valid(pbuf + devc->bufoffset)) {
bc653a56	255	log_dmm_packet(pbuf + devc->bufoffset);
f0540611 ML	256	decode_packet(sdi, pbuf + devc->bufoffset);
f0540611 ML	257	devc->bufoffset += dmm->packet_size;
bc653a56 UH	258	} else {
bc653a56 UH	259	devc->bufoffset++;
79081ec8	260	}
bc653a56	261	}
79081ec8	262
bc653a56 UH	263	/* Move remaining bytes to beginning of buffer. */
	264	for (i = 0; i < devc->buflen - devc->bufoffset; i++)
	265	pbuf[i] = pbuf[devc->bufoffset + i];
	266	devc->buflen -= devc->bufoffset;
79081ec8	267
bc653a56 UH	268	return SR_OK;
	269	}
	270
f0540611	271	SR_PRIV int uni_t_dmm_receive_data(int fd, int revents, void *cb_data)
bc653a56 UH	272	{
	273	int ret;
	274	struct sr_dev_inst *sdi;
	275	struct dev_context *devc;
c5ffac41	276	int64_t time_ms;
c8852687	277
bc653a56 UH	278	(void)fd;
bc653a56 UH	279	(void)revents;
c8852687	280
bc653a56 UH	281	sdi = cb_data;
bc653a56 UH	282	devc = sdi->priv;
c8852687	283
f0540611	284	if ((ret = get_and_handle_data(sdi)) != SR_OK)
bc653a56	285	return FALSE;
79081ec8 UH	286
79081ec8 UH	287	/* Abort acquisition if we acquired enough samples. */
35e199da	288	if (devc->limit_samples && devc->num_samples >= devc->limit_samples) {
79081ec8 UH	289	sr_info("Requested number of samples reached.");
	290	sdi->driver->dev_acquisition_stop(sdi, cb_data);
	291	}
	292
c5ffac41 UH	293	if (devc->limit_msec) {
	294	time_ms = (g_get_monotonic_time() - devc->starttime) / 1000;
	295	if (time_ms > (int64_t)devc->limit_msec) {
	296	sr_info("Requested time limit reached.");
	297	sdi->driver->dev_acquisition_stop(sdi, cb_data);
	298	return TRUE;
	299	}
	300	}
	301
79081ec8 UH	302	return TRUE;
79081ec8 UH	303	}