[libsigrok.git] / src / hardware / zketech-ebd-usb / protocol.c

/*
 * This file is part of the libsigrok project.
 *
 * Copyright (C) 2018 Sven Bursch-Osewold <sb_git@bursch.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 "protocol.h"

/* Log a byte-array as hex values. */
static void log_buf(const char *message, uint8_t buf[], size_t count)
{
	char buffer[count * 2 + 1];

	for (size_t j = 0; j < count; j++)
		sprintf(&buffer[2 * j], "%02X", buf[j]);

	buffer[count * 2] = 0;

	sr_dbg("%s: %s [%lu bytes]", message, buffer, count);
}

/* Send a command to the device. */
static int send_cmd(struct sr_serial_dev_inst *serial, uint8_t buf[], size_t count)
{
	int ret;

	log_buf("Sending", buf, count);
	ret = serial_write_blocking(serial, buf, count, 0);
	if (ret < 0) {
		sr_err("Error sending command: %d.", ret);
		return ret;
	}

	return (ret == (int)count) ? SR_OK : SR_ERR;
}

/* Decode high byte and low byte into a float. */
static float decode_value(uint8_t hi, uint8_t lo, float divisor)
{
	return ((float)hi * 240.0 + (float)lo) / divisor;
}

/* Encode a float into high byte and low byte. */
static void encode_value(float current, uint8_t *hi, uint8_t *lo, float divisor)
{
	int value;

	value = (int)(current * divisor);
	sr_dbg("Value %d %d %d", value, value / 240, value % 240);
	*hi = value / 240;
	*lo = value % 240;
}

/* Send updated configuration values to the load. */
static int send_cfg(struct sr_serial_dev_inst *serial, struct dev_context *devc)
{
	uint8_t send[] = { 0xfa, 0x07, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf8 };

	encode_value(devc->current_limit, &send[2], &send[3], 1000.0);

	send[8] = send[1] ^ send[2] ^ send[3] ^ send[4] ^ send[5] ^ \
			send[6] ^ send[7];

	return send_cmd(serial, send, 10);
}

/* Send the init/connect sequence; drive starts sending voltage and current. */
SR_PRIV int ebd_init(struct sr_serial_dev_inst *serial, struct dev_context *devc)
{
	uint8_t init[] = { 0xfa, 0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05, 0xf8 };

	(void)devc;

	int ret = send_cmd(serial, init, 10);
	if (ret == SR_OK)
		devc->running = TRUE;

	return ret;
}

/* Start the load functionality. */
SR_PRIV int ebd_loadstart(struct sr_serial_dev_inst *serial, struct dev_context *devc)
{
	uint8_t start[] = { 0xfa, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xf8 };
	int ret;

	ret = send_cmd(serial, start, 10);
	sr_dbg("Current limit: %f.", devc->current_limit);
	if (ebd_current_is0(devc))
		return SR_OK;

	ret = send_cfg(serial, devc);
	if (ret == SR_OK) {
		sr_dbg("Load activated.");
		devc->load_activated = TRUE;
	}

	return ret;
}

/* Stop the load functionality. */
SR_PRIV int ebd_loadstop(struct sr_serial_dev_inst *serial, struct dev_context *devc)
{
	int ret;
	uint8_t stop[] = { 0xfa, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xF8 };

	ret = send_cmd(serial, stop, 10);
	if (ret == SR_OK)
		devc->load_activated = FALSE;

	return ret;
}

/* Stop the drive. */
SR_PRIV int ebd_stop(struct sr_serial_dev_inst *serial, struct dev_context *devc)
{
	uint8_t stop[] = { 0xfa, 0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x06, 0xF8 };
	int ret;

	(void) devc;

	ret = send_cmd(serial, stop, 10);
	if (ret == SR_OK) {
		devc->load_activated = FALSE;
		devc->running= FALSE;
	}

	return ret;
}

/** Read count bytes from the serial connection. */
SR_PRIV int ebd_read_chars(struct sr_serial_dev_inst *serial, int count, uint8_t *buf)
{
	int ret, received, turns;

	received = 0;
	turns = 0;

	do {
		ret = serial_read_blocking(serial, buf + received,
			count - received, serial_timeout(serial, count));
		if (ret < 0) {
			sr_err("Error %d reading %d bytes.", ret, count);
			return ret;
		}
		received += ret;
		turns++;
	} while ((received < count) && (turns < 100));

	log_buf("Received", buf, received);

	return received;
}

SR_PRIV int ebd_receive_data(int fd, int revents, void *cb_data)
{
	struct sr_dev_inst *sdi;
	struct dev_context *devc;
	struct sr_serial_dev_inst *serial;
	struct sr_datafeed_packet packet;
	struct sr_datafeed_analog analog;
	struct sr_analog_encoding encoding;
	struct sr_analog_meaning meaning;
	struct sr_analog_spec spec;
	float voltage, current, current_limit;
	GSList *l;

	(void)revents;
	(void)fd;

	if (!(sdi = cb_data))
		return FALSE;

	if (!(devc = sdi->priv))
		return FALSE;

	serial = sdi->conn;

	uint8_t reply[MSG_LEN];
	int ret = ebd_read_chars(serial, MSG_LEN, reply);

	/* Tests for correct message. */
	if (ret != MSG_LEN) {
		sr_err("Message invalid [Len].");
		return (ret < 0) ? ret : SR_ERR;
	}

	uint8_t xor = reply[1] ^ reply[2] ^ reply[3] ^ reply[4] ^ \
		      reply[5] ^ reply[6] ^ reply[7] ^ reply[8] ^ \
		      reply[9] ^ reply[10] ^ reply[11] ^ reply[12] ^ \
		      reply[13] ^ reply[14] ^ reply[15] ^ reply[16];

	if (reply[MSG_FRAME_BEGIN_POS] != MSG_FRAME_BEGIN || \
			reply[MSG_FRAME_END_POS] != MSG_FRAME_END || \
			xor != reply[MSG_CHECKSUM_POS]) {
		sr_err("Message invalid [XOR, BEGIN/END].");
		return SR_ERR;
	}

	/* Calculate values. */
	sr_dbg("V: %02X %02X A: %02X %02X -- Limit %02X %02X", reply[4],
		reply[5], reply[2], reply[3], reply[10], reply[11]);

	voltage = decode_value(reply[4], reply[5], 1000.0);
	current = decode_value(reply[2], reply[3], 10000.0);
	current_limit = decode_value(reply[10], reply[11], 1000.0);

	sr_dbg("Voltage %f", voltage);
	sr_dbg("Current %f", current);
	sr_dbg("Current limit %f", current_limit);

	/* Begin frame. */
	packet.type = SR_DF_FRAME_BEGIN;
	packet.payload = NULL;
	sr_session_send(sdi, &packet);

	sr_analog_init(&analog, &encoding, &meaning, &spec, 4);

	packet.type = SR_DF_ANALOG;
	packet.payload = &analog;
	analog.num_samples = 1;

	/* Voltage */
	l = g_slist_copy(sdi->channels);
	l = g_slist_remove_link(l, g_slist_nth(l, 1));
	meaning.channels = l;
	meaning.mq = SR_MQ_VOLTAGE;
	meaning.mqflags = SR_MQFLAG_DC;
	meaning.unit = SR_UNIT_VOLT;
	analog.data = &voltage;
	sr_session_send(sdi, &packet);
	g_slist_free(l);

	/* Current */
	l = g_slist_copy(sdi->channels);
	l = g_slist_remove_link(l, g_slist_nth(l, 0));
	meaning.channels = l;
	meaning.mq = SR_MQ_CURRENT;
	meaning.mqflags = SR_MQFLAG_DC;
	meaning.unit = SR_UNIT_AMPERE;
	analog.data = &current;
	sr_session_send(sdi, &packet);
	g_slist_free(l);

	/* End frame. */
	packet.type = SR_DF_FRAME_END;
	packet.payload = NULL;
	sr_session_send(sdi, &packet);

	sr_sw_limits_update_samples_read(&devc->limits, 1);
	if (sr_sw_limits_check(&devc->limits))
		sr_dev_acquisition_stop(sdi);

	return TRUE;
}

SR_PRIV int ebd_get_current_limit(const struct sr_dev_inst *sdi, float *current)
{
	struct dev_context *devc;

	if (!(devc = sdi->priv))
		return SR_ERR;

	g_mutex_lock(&devc->rw_mutex);
	*current = devc->current_limit;
	g_mutex_unlock(&devc->rw_mutex);

	return SR_OK;
}

SR_PRIV int ebd_set_current_limit(const struct sr_dev_inst *sdi, float current)
{
	struct dev_context *devc;
	int ret;

	if (!(devc = sdi->priv))
		return SR_ERR;

	g_mutex_lock(&devc->rw_mutex);
	devc->current_limit = current;

	if (!devc->running) {
		sr_dbg("Setting current limit later.");
		g_mutex_unlock(&devc->rw_mutex);
		return SR_OK;
	}

	sr_dbg("Setting current limit to %fV.", current);

	if (devc->load_activated) {
		if (ebd_current_is0(devc)) {
			/* Stop load. */
			ret = ebd_loadstop(sdi->conn, devc);
		} else {
			/* Send new current. */
			ret = send_cfg(sdi->conn, devc);
		}
	} else {
		if (ebd_current_is0(devc)) {
			/* Nothing to do. */
			ret = SR_OK;
		} else {
			/* Start load. */
			ret = ebd_loadstart(sdi->conn, devc);
		}
	}

	g_mutex_unlock(&devc->rw_mutex);

	return ret;
}

SR_PRIV gboolean ebd_current_is0(struct dev_context *devc)
{
	return devc->current_limit < 0.001;
}
Commit	Line	Data
c527132a SBO	1	/*
	2	* This file is part of the libsigrok project.
	3	*
	4	* Copyright (C) 2018 Sven Bursch-Osewold <sb_git@bursch.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 "protocol.h"
	22
cb8a0efc UH	23	/* Log a byte-array as hex values. */
	24	static void log_buf(const char *message, uint8_t buf[], size_t count)
	25	{
	26	char buffer[count * 2 + 1];
	27
	28	for (size_t j = 0; j < count; j++)
	29	sprintf(&buffer[2 * j], "%02X", buf[j]);
	30
	31	buffer[count * 2] = 0;
	32
	33	sr_dbg("%s: %s [%lu bytes]", message, buffer, count);
	34	}
	35
9890fb1f	36	/* Send a command to the device. */
cb8a0efc	37	static int send_cmd(struct sr_serial_dev_inst *serial, uint8_t buf[], size_t count)
9890fb1f SBO	38	{
	39	int ret;
	40
cb8a0efc	41	log_buf("Sending", buf, count);
9890fb1f SBO	42	ret = serial_write_blocking(serial, buf, count, 0);
	43	if (ret < 0) {
	44	sr_err("Error sending command: %d.", ret);
	45	return ret;
	46	}
9890fb1f SBO	47
	48	return (ret == (int)count) ? SR_OK : SR_ERR;
	49	}
	50
cb8a0efc UH	51	/* Decode high byte and low byte into a float. */
	52	static float decode_value(uint8_t hi, uint8_t lo, float divisor)
	53	{
	54	return ((float)hi * 240.0 + (float)lo) / divisor;
	55	}
	56
	57	/* Encode a float into high byte and low byte. */
	58	static void encode_value(float current, uint8_t hi, uint8_t lo, float divisor)
	59	{
	60	int value;
	61
	62	value = (int)(current * divisor);
	63	sr_dbg("Value %d %d %d", value, value / 240, value % 240);
	64	*hi = value / 240;
	65	*lo = value % 240;
	66	}
	67
	68	/* Send updated configuration values to the load. */
	69	static int send_cfg(struct sr_serial_dev_inst serial, struct dev_context devc)
	70	{
	71	uint8_t send[] = { 0xfa, 0x07, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf8 };
	72
	73	encode_value(devc->current_limit, &send[2], &send[3], 1000.0);
	74
	75	send[8] = send[1] ^ send[2] ^ send[3] ^ send[4] ^ send[5] ^ \
	76	send[6] ^ send[7];
	77
	78	return send_cmd(serial, send, 10);
	79	}
	80
9890fb1f	81	/* Send the init/connect sequence; drive starts sending voltage and current. */
330a32b2	82	SR_PRIV int ebd_init(struct sr_serial_dev_inst serial, struct dev_context devc)
9890fb1f SBO	83	{
	84	uint8_t init[] = { 0xfa, 0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05, 0xf8 };
	85
	86	(void)devc;
	87
cb8a0efc	88	int ret = send_cmd(serial, init, 10);
9890fb1f SBO	89	if (ret == SR_OK)
	90	devc->running = TRUE;
	91
	92	return ret;
	93	}
	94
	95	/* Start the load functionality. */
330a32b2	96	SR_PRIV int ebd_loadstart(struct sr_serial_dev_inst serial, struct dev_context devc)
9890fb1f SBO	97	{
	98	uint8_t start[] = { 0xfa, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xf8 };
	99	int ret;
	100
cb8a0efc	101	ret = send_cmd(serial, start, 10);
9890fb1f	102	sr_dbg("Current limit: %f.", devc->current_limit);
330a32b2	103	if (ebd_current_is0(devc))
9890fb1f SBO	104	return SR_OK;
9890fb1f SBO	105
cb8a0efc	106	ret = send_cfg(serial, devc);
9890fb1f SBO	107	if (ret == SR_OK) {
	108	sr_dbg("Load activated.");
	109	devc->load_activated = TRUE;
	110	}
	111
	112	return ret;
	113	}
	114
	115	/* Stop the load functionality. */
330a32b2	116	SR_PRIV int ebd_loadstop(struct sr_serial_dev_inst serial, struct dev_context devc)
9890fb1f SBO	117	{
	118	int ret;
	119	uint8_t stop[] = { 0xfa, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xF8 };
	120
cb8a0efc	121	ret = send_cmd(serial, stop, 10);
9890fb1f SBO	122	if (ret == SR_OK)
	123	devc->load_activated = FALSE;
	124
	125	return ret;
	126	}
	127
	128	/* Stop the drive. */
330a32b2	129	SR_PRIV int ebd_stop(struct sr_serial_dev_inst serial, struct dev_context devc)
9890fb1f SBO	130	{
	131	uint8_t stop[] = { 0xfa, 0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x06, 0xF8 };
	132	int ret;
	133
	134	(void) devc;
	135
cb8a0efc	136	ret = send_cmd(serial, stop, 10);
9890fb1f SBO	137	if (ret == SR_OK) {
	138	devc->load_activated = FALSE;
	139	devc->running= FALSE;
	140	}
	141
	142	return ret;
	143	}
	144
9890fb1f	145	/** Read count bytes from the serial connection. */
330a32b2	146	SR_PRIV int ebd_read_chars(struct sr_serial_dev_inst serial, int count, uint8_t buf)
9890fb1f SBO	147	{
	148	int ret, received, turns;
	149
	150	received = 0;
	151	turns = 0;
	152
	153	do {
	154	ret = serial_read_blocking(serial, buf + received,
	155	count - received, serial_timeout(serial, count));
	156	if (ret < 0) {
	157	sr_err("Error %d reading %d bytes.", ret, count);
	158	return ret;
	159	}
	160	received += ret;
	161	turns++;
	162	} while ((received < count) && (turns < 100));
	163
cb8a0efc	164	log_buf("Received", buf, received);
9890fb1f SBO	165
	166	return received;
	167	}
	168
330a32b2	169	SR_PRIV int ebd_receive_data(int fd, int revents, void *cb_data)
c527132a	170	{
9890fb1f	171	struct sr_dev_inst *sdi;
c527132a	172	struct dev_context *devc;
9890fb1f SBO	173	struct sr_serial_dev_inst *serial;
	174	struct sr_datafeed_packet packet;
	175	struct sr_datafeed_analog analog;
	176	struct sr_analog_encoding encoding;
	177	struct sr_analog_meaning meaning;
	178	struct sr_analog_spec spec;
	179	float voltage, current, current_limit;
	180	GSList *l;
c527132a	181
9890fb1f	182	(void)revents;
c527132a SBO	183	(void)fd;
	184
	185	if (!(sdi = cb_data))
9890fb1f	186	return FALSE;
c527132a SBO	187
c527132a SBO	188	if (!(devc = sdi->priv))
9890fb1f SBO	189	return FALSE;
	190
	191	serial = sdi->conn;
	192
ec4806dc	193	uint8_t reply[MSG_LEN];
330a32b2	194	int ret = ebd_read_chars(serial, MSG_LEN, reply);
9890fb1f SBO	195
9890fb1f SBO	196	/* Tests for correct message. */
ec4806dc	197	if (ret != MSG_LEN) {
9890fb1f SBO	198	sr_err("Message invalid [Len].");
	199	return (ret < 0) ? ret : SR_ERR;
	200	}
c527132a	201
9890fb1f SBO	202	uint8_t xor = reply[1] ^ reply[2] ^ reply[3] ^ reply[4] ^ \
	203	reply[5] ^ reply[6] ^ reply[7] ^ reply[8] ^ \
	204	reply[9] ^ reply[10] ^ reply[11] ^ reply[12] ^ \
	205	reply[13] ^ reply[14] ^ reply[15] ^ reply[16];
	206
ec4806dc UH	207	if (reply[MSG_FRAME_BEGIN_POS] != MSG_FRAME_BEGIN \|\| \
	208	reply[MSG_FRAME_END_POS] != MSG_FRAME_END \|\| \
	209	xor != reply[MSG_CHECKSUM_POS]) {
9890fb1f SBO	210	sr_err("Message invalid [XOR, BEGIN/END].");
9890fb1f SBO	211	return SR_ERR;
c527132a SBO	212	}
c527132a SBO	213
9890fb1f SBO	214	/* Calculate values. */
	215	sr_dbg("V: %02X %02X A: %02X %02X -- Limit %02X %02X", reply[4],
	216	reply[5], reply[2], reply[3], reply[10], reply[11]);
	217
cb8a0efc UH	218	voltage = decode_value(reply[4], reply[5], 1000.0);
	219	current = decode_value(reply[2], reply[3], 10000.0);
	220	current_limit = decode_value(reply[10], reply[11], 1000.0);
9890fb1f SBO	221
	222	sr_dbg("Voltage %f", voltage);
	223	sr_dbg("Current %f", current);
	224	sr_dbg("Current limit %f", current_limit);
	225
	226	/* Begin frame. */
	227	packet.type = SR_DF_FRAME_BEGIN;
	228	packet.payload = NULL;
	229	sr_session_send(sdi, &packet);
	230
	231	sr_analog_init(&analog, &encoding, &meaning, &spec, 4);
	232
	233	packet.type = SR_DF_ANALOG;
	234	packet.payload = &analog;
	235	analog.num_samples = 1;
	236
	237	/* Voltage */
	238	l = g_slist_copy(sdi->channels);
	239	l = g_slist_remove_link(l, g_slist_nth(l, 1));
	240	meaning.channels = l;
	241	meaning.mq = SR_MQ_VOLTAGE;
	242	meaning.mqflags = SR_MQFLAG_DC;
	243	meaning.unit = SR_UNIT_VOLT;
	244	analog.data = &voltage;
	245	sr_session_send(sdi, &packet);
	246	g_slist_free(l);
	247
	248	/* Current */
	249	l = g_slist_copy(sdi->channels);
	250	l = g_slist_remove_link(l, g_slist_nth(l, 0));
	251	meaning.channels = l;
	252	meaning.mq = SR_MQ_CURRENT;
	253	meaning.mqflags = SR_MQFLAG_DC;
	254	meaning.unit = SR_UNIT_AMPERE;
	255	analog.data = &current;
	256	sr_session_send(sdi, &packet);
	257	g_slist_free(l);
	258
	259	/* End frame. */
	260	packet.type = SR_DF_FRAME_END;
	261	packet.payload = NULL;
	262	sr_session_send(sdi, &packet);
	263
	264	sr_sw_limits_update_samples_read(&devc->limits, 1);
	265	if (sr_sw_limits_check(&devc->limits))
	266	sr_dev_acquisition_stop(sdi);
	267
c527132a SBO	268	return TRUE;
c527132a SBO	269	}
9890fb1f	270
330a32b2	271	SR_PRIV int ebd_get_current_limit(const struct sr_dev_inst sdi, float current)
9890fb1f SBO	272	{
	273	struct dev_context *devc;
	274
	275	if (!(devc = sdi->priv))
	276	return SR_ERR;
	277
	278	g_mutex_lock(&devc->rw_mutex);
	279	*current = devc->current_limit;
	280	g_mutex_unlock(&devc->rw_mutex);
	281
	282	return SR_OK;
	283	}
	284
330a32b2	285	SR_PRIV int ebd_set_current_limit(const struct sr_dev_inst *sdi, float current)
9890fb1f SBO	286	{
	287	struct dev_context *devc;
	288	int ret;
	289
	290	if (!(devc = sdi->priv))
	291	return SR_ERR;
	292
	293	g_mutex_lock(&devc->rw_mutex);
	294	devc->current_limit = current;
	295
	296	if (!devc->running) {
	297	sr_dbg("Setting current limit later.");
	298	g_mutex_unlock(&devc->rw_mutex);
	299	return SR_OK;
	300	}
	301
	302	sr_dbg("Setting current limit to %fV.", current);
	303
	304	if (devc->load_activated) {
330a32b2	305	if (ebd_current_is0(devc)) {
9890fb1f	306	/* Stop load. */
330a32b2	307	ret = ebd_loadstop(sdi->conn, devc);
9890fb1f SBO	308	} else {
9890fb1f SBO	309	/* Send new current. */
cb8a0efc	310	ret = send_cfg(sdi->conn, devc);
9890fb1f SBO	311	}
9890fb1f SBO	312	} else {
330a32b2	313	if (ebd_current_is0(devc)) {
9890fb1f SBO	314	/* Nothing to do. */
	315	ret = SR_OK;
	316	} else {
	317	/* Start load. */
330a32b2	318	ret = ebd_loadstart(sdi->conn, devc);
9890fb1f SBO	319	}
	320	}
	321
	322	g_mutex_unlock(&devc->rw_mutex);
	323
	324	return ret;
	325	}
	326
330a32b2	327	SR_PRIV gboolean ebd_current_is0(struct dev_context *devc)
9890fb1f SBO	328	{
	329	return devc->current_limit < 0.001;
	330	}