2 * This file is part of the libsigrok project.
4 * Copyright (C) 2014 Janne Huttunen <jahuttun@gmail.com>
5 * Copyright (C) 2019 Gerhard Sittig <gerhard.sittig@gmx.net>
7 * This program is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 3 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program. If not, see <http://www.gnu.org/licenses/>.
21 #include <libsigrok/libsigrok.h>
22 #include <libsigrok-internal.h>
28 static void send_frame_start(struct sr_dev_inst *sdi)
30 struct dev_context *devc;
31 struct lcr_parse_info *info;
36 info = &devc->parse_info;
38 /* Communicate changes of frequency or model before data values. */
39 freq = info->output_freq;
40 if (freq != devc->output_freq) {
41 devc->output_freq = freq;
42 sr_session_send_meta(sdi, SR_CONF_OUTPUT_FREQUENCY,
43 g_variant_new_double(freq));
45 model = info->circuit_model;
46 if (model && model != devc->circuit_model) {
47 devc->circuit_model = model;
48 sr_session_send_meta(sdi, SR_CONF_EQUIV_CIRCUIT_MODEL,
49 g_variant_new_string(model));
52 /* Data is about to get sent. Start a new frame. */
53 std_session_send_df_frame_begin(sdi);
56 static int handle_packet(struct sr_dev_inst *sdi, const uint8_t *pkt)
58 struct dev_context *devc;
59 struct lcr_parse_info *info;
60 const struct lcr_info *lcr;
64 struct sr_datafeed_packet packet;
65 struct sr_datafeed_analog analog;
66 struct sr_analog_encoding encoding;
67 struct sr_analog_meaning meaning;
68 struct sr_analog_spec spec;
70 struct sr_channel *channel;
73 info = &devc->parse_info;
76 /* Note: digits/spec_digits will be overridden later. */
77 sr_analog_init(&analog, &encoding, &meaning, &spec, 0);
78 analog.num_samples = 1;
82 for (ch_idx = 0; ch_idx < lcr->channel_count; ch_idx++) {
83 channel = g_slist_nth_data(sdi->channels, ch_idx);
84 analog.meaning->channels = g_slist_append(NULL, channel);
85 info->ch_idx = ch_idx;
86 rc = lcr->packet_parse(pkt, &value, &analog, info);
87 if (sdi->session && rc == SR_OK && analog.meaning->mq && channel->enabled) {
89 send_frame_start(sdi);
92 packet.type = SR_DF_ANALOG;
93 packet.payload = &analog;
94 sr_session_send(sdi, &packet);
96 g_slist_free(analog.meaning->channels);
99 std_session_send_df_frame_end(sdi);
100 sr_sw_limits_update_frames_read(&devc->limits, 1);
106 static int handle_new_data(struct sr_dev_inst *sdi)
108 struct dev_context *devc;
109 struct sr_serial_dev_inst *serial;
111 const struct lcr_info *lcr;
118 /* Read another chunk of data into the buffer. */
119 rdsize = sizeof(devc->buf) - devc->buf_rxpos;
120 rdsize = serial_read_nonblocking(serial, &devc->buf[devc->buf_rxpos], rdsize);
123 devc->buf_rxpos += rdsize;
126 * Process as many packets as the buffer might contain. Assume
127 * that the stream is synchronized in the typical case. Re-sync
128 * in case of mismatch (skip individual bytes until data matches
129 * the expected packet layout again).
131 lcr = devc->lcr_info;
132 while (devc->buf_rxpos >= lcr->packet_size) {
134 if (!lcr->packet_valid(pkt)) {
135 copy_len = devc->buf_rxpos - 1;
136 memmove(&devc->buf[0], &devc->buf[1], copy_len);
140 (void)handle_packet(sdi, pkt);
141 copy_len = devc->buf_rxpos - lcr->packet_size;
142 memmove(&devc->buf[0], &devc->buf[lcr->packet_size], copy_len);
143 devc->buf_rxpos -= lcr->packet_size;
149 static int handle_timeout(struct sr_dev_inst *sdi)
151 struct dev_context *devc;
152 const struct lcr_info *lcr;
153 struct sr_serial_dev_inst *serial;
158 lcr = devc->lcr_info;
160 if (!lcr->packet_request)
163 now = g_get_monotonic_time();
164 if (devc->req_next_at && now < devc->req_next_at)
168 ret = lcr->packet_request(serial);
170 sr_err("Failed to request packet: %d.", ret);
174 if (lcr->req_timeout_ms)
175 devc->req_next_at = now + lcr->req_timeout_ms * 1000;
180 SR_PRIV int lcr_receive_data(int fd, int revents, void *cb_data)
182 struct sr_dev_inst *sdi;
183 struct dev_context *devc;
188 if (!(sdi = cb_data))
190 if (!(devc = sdi->priv))
193 if (revents == G_IO_IN)
194 ret = handle_new_data(sdi);
196 ret = handle_timeout(sdi);
197 if (sr_sw_limits_check(&devc->limits))
198 sr_dev_acquisition_stop(sdi);