[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 [%zu 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);
	if (ret)
		return ret;

	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. */
	std_session_send_df_frame_begin(sdi);

	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. */
	std_session_send_df_frame_end(sdi);

	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
b8a954c5	33	sr_dbg("%s: %s [%zu bytes]", message, buffer, count);
cb8a0efc UH	34	}
cb8a0efc UH	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);
b41562f6 FR	102	if (ret)
	103	return ret;
	104
9890fb1f	105	sr_dbg("Current limit: %f.", devc->current_limit);
330a32b2	106	if (ebd_current_is0(devc))
9890fb1f SBO	107	return SR_OK;
9890fb1f SBO	108
cb8a0efc	109	ret = send_cfg(serial, devc);
9890fb1f SBO	110	if (ret == SR_OK) {
	111	sr_dbg("Load activated.");
	112	devc->load_activated = TRUE;
	113	}
	114
	115	return ret;
	116	}
	117
	118	/* Stop the load functionality. */
330a32b2	119	SR_PRIV int ebd_loadstop(struct sr_serial_dev_inst serial, struct dev_context devc)
9890fb1f SBO	120	{
	121	int ret;
	122	uint8_t stop[] = { 0xfa, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xF8 };
	123
cb8a0efc	124	ret = send_cmd(serial, stop, 10);
9890fb1f SBO	125	if (ret == SR_OK)
	126	devc->load_activated = FALSE;
	127
	128	return ret;
	129	}
	130
	131	/* Stop the drive. */
330a32b2	132	SR_PRIV int ebd_stop(struct sr_serial_dev_inst serial, struct dev_context devc)
9890fb1f SBO	133	{
	134	uint8_t stop[] = { 0xfa, 0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x06, 0xF8 };
	135	int ret;
	136
	137	(void) devc;
	138
cb8a0efc	139	ret = send_cmd(serial, stop, 10);
9890fb1f SBO	140	if (ret == SR_OK) {
	141	devc->load_activated = FALSE;
	142	devc->running= FALSE;
	143	}
	144
	145	return ret;
	146	}
	147
9890fb1f	148	/** Read count bytes from the serial connection. */
330a32b2	149	SR_PRIV int ebd_read_chars(struct sr_serial_dev_inst serial, int count, uint8_t buf)
9890fb1f SBO	150	{
	151	int ret, received, turns;
	152
	153	received = 0;
	154	turns = 0;
	155
	156	do {
	157	ret = serial_read_blocking(serial, buf + received,
	158	count - received, serial_timeout(serial, count));
	159	if (ret < 0) {
	160	sr_err("Error %d reading %d bytes.", ret, count);
	161	return ret;
	162	}
	163	received += ret;
	164	turns++;
	165	} while ((received < count) && (turns < 100));
	166
cb8a0efc	167	log_buf("Received", buf, received);
9890fb1f SBO	168
	169	return received;
	170	}
	171
330a32b2	172	SR_PRIV int ebd_receive_data(int fd, int revents, void *cb_data)
c527132a	173	{
9890fb1f	174	struct sr_dev_inst *sdi;
c527132a	175	struct dev_context *devc;
9890fb1f SBO	176	struct sr_serial_dev_inst *serial;
	177	struct sr_datafeed_packet packet;
	178	struct sr_datafeed_analog analog;
	179	struct sr_analog_encoding encoding;
	180	struct sr_analog_meaning meaning;
	181	struct sr_analog_spec spec;
	182	float voltage, current, current_limit;
	183	GSList *l;
c527132a	184
9890fb1f	185	(void)revents;
c527132a SBO	186	(void)fd;
	187
	188	if (!(sdi = cb_data))
9890fb1f	189	return FALSE;
c527132a SBO	190
c527132a SBO	191	if (!(devc = sdi->priv))
9890fb1f SBO	192	return FALSE;
	193
	194	serial = sdi->conn;
	195
ec4806dc	196	uint8_t reply[MSG_LEN];
330a32b2	197	int ret = ebd_read_chars(serial, MSG_LEN, reply);
9890fb1f SBO	198
9890fb1f SBO	199	/* Tests for correct message. */
ec4806dc	200	if (ret != MSG_LEN) {
9890fb1f SBO	201	sr_err("Message invalid [Len].");
	202	return (ret < 0) ? ret : SR_ERR;
	203	}
c527132a	204
9890fb1f SBO	205	uint8_t xor = reply[1] ^ reply[2] ^ reply[3] ^ reply[4] ^ \
	206	reply[5] ^ reply[6] ^ reply[7] ^ reply[8] ^ \
	207	reply[9] ^ reply[10] ^ reply[11] ^ reply[12] ^ \
	208	reply[13] ^ reply[14] ^ reply[15] ^ reply[16];
	209
ec4806dc UH	210	if (reply[MSG_FRAME_BEGIN_POS] != MSG_FRAME_BEGIN \|\| \
	211	reply[MSG_FRAME_END_POS] != MSG_FRAME_END \|\| \
	212	xor != reply[MSG_CHECKSUM_POS]) {
9890fb1f SBO	213	sr_err("Message invalid [XOR, BEGIN/END].");
9890fb1f SBO	214	return SR_ERR;
c527132a SBO	215	}
c527132a SBO	216
9890fb1f SBO	217	/* Calculate values. */
	218	sr_dbg("V: %02X %02X A: %02X %02X -- Limit %02X %02X", reply[4],
	219	reply[5], reply[2], reply[3], reply[10], reply[11]);
	220
cb8a0efc UH	221	voltage = decode_value(reply[4], reply[5], 1000.0);
	222	current = decode_value(reply[2], reply[3], 10000.0);
	223	current_limit = decode_value(reply[10], reply[11], 1000.0);
9890fb1f SBO	224
	225	sr_dbg("Voltage %f", voltage);
	226	sr_dbg("Current %f", current);
	227	sr_dbg("Current limit %f", current_limit);
	228
	229	/* Begin frame. */
4c5f7006	230	std_session_send_df_frame_begin(sdi);
9890fb1f SBO	231
	232	sr_analog_init(&analog, &encoding, &meaning, &spec, 4);
	233
	234	packet.type = SR_DF_ANALOG;
	235	packet.payload = &analog;
	236	analog.num_samples = 1;
	237
	238	/* Voltage */
	239	l = g_slist_copy(sdi->channels);
	240	l = g_slist_remove_link(l, g_slist_nth(l, 1));
	241	meaning.channels = l;
	242	meaning.mq = SR_MQ_VOLTAGE;
	243	meaning.mqflags = SR_MQFLAG_DC;
	244	meaning.unit = SR_UNIT_VOLT;
	245	analog.data = &voltage;
	246	sr_session_send(sdi, &packet);
	247	g_slist_free(l);
	248
	249	/* Current */
	250	l = g_slist_copy(sdi->channels);
	251	l = g_slist_remove_link(l, g_slist_nth(l, 0));
	252	meaning.channels = l;
	253	meaning.mq = SR_MQ_CURRENT;
	254	meaning.mqflags = SR_MQFLAG_DC;
	255	meaning.unit = SR_UNIT_AMPERE;
	256	analog.data = &current;
	257	sr_session_send(sdi, &packet);
	258	g_slist_free(l);
	259
	260	/* End frame. */
4c5f7006	261	std_session_send_df_frame_end(sdi);
9890fb1f SBO	262
	263	sr_sw_limits_update_samples_read(&devc->limits, 1);
	264	if (sr_sw_limits_check(&devc->limits))
	265	sr_dev_acquisition_stop(sdi);
	266
c527132a SBO	267	return TRUE;
c527132a SBO	268	}
9890fb1f	269
330a32b2	270	SR_PRIV int ebd_get_current_limit(const struct sr_dev_inst sdi, float current)
9890fb1f SBO	271	{
	272	struct dev_context *devc;
	273
	274	if (!(devc = sdi->priv))
	275	return SR_ERR;
	276
	277	g_mutex_lock(&devc->rw_mutex);
	278	*current = devc->current_limit;
	279	g_mutex_unlock(&devc->rw_mutex);
	280
	281	return SR_OK;
	282	}
	283
330a32b2	284	SR_PRIV int ebd_set_current_limit(const struct sr_dev_inst *sdi, float current)
9890fb1f SBO	285	{
	286	struct dev_context *devc;
	287	int ret;
	288
	289	if (!(devc = sdi->priv))
	290	return SR_ERR;
	291
	292	g_mutex_lock(&devc->rw_mutex);
	293	devc->current_limit = current;
	294
	295	if (!devc->running) {
	296	sr_dbg("Setting current limit later.");
	297	g_mutex_unlock(&devc->rw_mutex);
	298	return SR_OK;
	299	}
	300
	301	sr_dbg("Setting current limit to %fV.", current);
	302
	303	if (devc->load_activated) {
330a32b2	304	if (ebd_current_is0(devc)) {
9890fb1f	305	/* Stop load. */
330a32b2	306	ret = ebd_loadstop(sdi->conn, devc);
9890fb1f SBO	307	} else {
9890fb1f SBO	308	/* Send new current. */
cb8a0efc	309	ret = send_cfg(sdi->conn, devc);
9890fb1f SBO	310	}
9890fb1f SBO	311	} else {
330a32b2	312	if (ebd_current_is0(devc)) {
9890fb1f SBO	313	/* Nothing to do. */
	314	ret = SR_OK;
	315	} else {
	316	/* Start load. */
330a32b2	317	ret = ebd_loadstart(sdi->conn, devc);
9890fb1f SBO	318	}
	319	}
	320
	321	g_mutex_unlock(&devc->rw_mutex);
	322
	323	return ret;
	324	}
	325
330a32b2	326	SR_PRIV gboolean ebd_current_is0(struct dev_context *devc)
9890fb1f SBO	327	{
	328	return devc->current_limit < 0.001;
	329	}