From: Daniel Elstner Date: Tue, 22 Sep 2015 04:49:17 +0000 (+0200) Subject: demo: Fix continuous mode and honor time limit X-Git-Tag: libsigrok-0.4.0~254 X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=a49a320deaddbcc8caedb3247a695b97e22b37b3;p=libsigrok.git demo: Fix continuous mode and honor time limit Also deal more gracefully with changes to the samplerate while running. --- diff --git a/src/hardware/demo/demo.c b/src/hardware/demo/demo.c index f1163ef8..ce824918 100644 --- a/src/hardware/demo/demo.c +++ b/src/hardware/demo/demo.c @@ -106,12 +106,11 @@ struct analog_gen { /* Private, per-device-instance driver context. */ struct dev_context { uint64_t cur_samplerate; - gboolean continuous; uint64_t limit_samples; uint64_t limit_msec; - uint64_t logic_counter; - uint64_t analog_counter; - int64_t starttime; + uint64_t sent_samples; + int64_t start_us; + int64_t spent_us; uint64_t step; /* Logic */ int32_t num_logic_channels; @@ -294,18 +293,12 @@ static GSList *scan(struct sr_dev_driver *di, GSList *options) sdi->model = g_strdup("Demo device"); sdi->driver = di; - devc = g_malloc(sizeof(struct dev_context)); + devc = g_malloc0(sizeof(struct dev_context)); devc->cur_samplerate = SR_KHZ(200); - devc->limit_samples = 0; - devc->limit_msec = 0; - devc->step = 0; - devc->continuous = FALSE; devc->num_logic_channels = num_logic_channels; devc->logic_unitsize = (devc->num_logic_channels + 7) / 8; devc->logic_pattern = PATTERN_SIGROK; devc->num_analog_channels = num_analog_channels; - devc->avg = FALSE; - devc->avg_samples = 0; /* Logic channels, all in one channel group. */ cg = g_malloc0(sizeof(struct sr_channel_group)); @@ -684,6 +677,7 @@ static void logic_generator(struct sr_dev_inst *sdi, uint64_t size) static void send_analog_packet(struct analog_gen *ag, struct sr_dev_inst *sdi, uint64_t *analog_sent, + uint64_t analog_pos, uint64_t analog_todo) { struct sr_datafeed_packet packet; @@ -697,7 +691,7 @@ static void send_analog_packet(struct analog_gen *ag, packet.payload = &ag->packet; if (!devc->avg) { - ag_pattern_pos = devc->analog_counter % ag->num_samples; + ag_pattern_pos = analog_pos % ag->num_samples; sending_now = MIN(analog_todo, ag->num_samples-ag_pattern_pos); ag->packet.data = ag->pattern_data + ag_pattern_pos; ag->packet.num_samples = sending_now; @@ -706,7 +700,7 @@ static void send_analog_packet(struct analog_gen *ag, /* Whichever channel group gets there first. */ *analog_sent = MAX(*analog_sent, sending_now); } else { - ag_pattern_pos = devc->analog_counter % ag->num_samples; + ag_pattern_pos = analog_pos % ag->num_samples; to_avg = MIN(analog_todo, ag->num_samples-ag_pattern_pos); for (i = 0; i < to_avg; i++) { @@ -750,35 +744,54 @@ static int prepare_data(int fd, int revents, void *cb_data) struct analog_gen *ag; GHashTableIter iter; void *value; - uint64_t logic_todo, analog_todo, expected_samplenum, analog_sent, sending_now; - int64_t time, elapsed; + uint64_t samples_todo, logic_done, analog_done, analog_sent, sending_now; + int64_t elapsed_us, limit_us, todo_us; (void)fd; (void)revents; sdi = cb_data; devc = sdi->priv; - logic_todo = analog_todo = 0; - /* How many samples should we have sent by now? */ - time = g_get_monotonic_time(); - elapsed = time - devc->starttime; - expected_samplenum = elapsed * devc->cur_samplerate / (1000 * 1000); + /* Just in case. */ + if (devc->cur_samplerate <= 0 || devc->logic_unitsize <= 0 + || (devc->num_logic_channels <= 0 + && devc->num_analog_channels <= 0)) { + dev_acquisition_stop(sdi, sdi); + return G_SOURCE_CONTINUE; + } - /* But never more than the limit, if there is one. */ - if (!devc->continuous) - expected_samplenum = MIN(expected_samplenum, devc->limit_samples); + /* What time span should we send samples for? */ + elapsed_us = g_get_monotonic_time() - devc->start_us; + limit_us = 1000 * devc->limit_msec; + if (limit_us > 0 && limit_us < elapsed_us) + todo_us = MAX(0, limit_us - devc->spent_us); + else + todo_us = MAX(0, elapsed_us - devc->spent_us); + + /* How many samples are outstanding since the last round? */ + samples_todo = (todo_us * devc->cur_samplerate + G_USEC_PER_SEC / 2) + / G_USEC_PER_SEC; + if (devc->limit_samples > 0) { + if (devc->limit_samples < devc->sent_samples) + samples_todo = 0; + else if (devc->limit_samples - devc->sent_samples < samples_todo) + samples_todo = devc->limit_samples - devc->sent_samples; + } + /* Calculate the actual time covered by this run back from the sample + * count, rounded towards zero. This avoids getting stuck on a too-low + * time delta with no samples being sent due to round-off. + */ + todo_us = samples_todo * G_USEC_PER_SEC / devc->cur_samplerate; - /* Of those, how many do we still have to send? */ - if (devc->num_logic_channels && (devc->logic_counter < devc->limit_samples)) - logic_todo = expected_samplenum - devc->logic_counter; - if (devc->num_analog_channels && (devc->analog_counter < devc->limit_samples)) - analog_todo = expected_samplenum - devc->analog_counter; + logic_done = 0; + analog_done = 0; - while (logic_todo || analog_todo) { + while (logic_done < samples_todo || analog_done < samples_todo) { /* Logic */ - if (logic_todo > 0) { - sending_now = MIN(logic_todo, LOGIC_BUFSIZE / devc->logic_unitsize); + if (logic_done < samples_todo) { + sending_now = MIN(samples_todo - logic_done, + LOGIC_BUFSIZE / devc->logic_unitsize); logic_generator(sdi, sending_now * devc->logic_unitsize); packet.type = SR_DF_LOGIC; packet.payload = &logic; @@ -786,27 +799,35 @@ static int prepare_data(int fd, int revents, void *cb_data) logic.unitsize = devc->logic_unitsize; logic.data = devc->logic_data; sr_session_send(sdi, &packet); - logic_todo -= sending_now; - devc->logic_counter += sending_now; + logic_done += sending_now; } /* Analog, one channel at a time */ - if (analog_todo > 0) { + if (analog_done < samples_todo) { analog_sent = 0; g_hash_table_iter_init(&iter, devc->ch_ag); while (g_hash_table_iter_next(&iter, NULL, &value)) { - send_analog_packet(value, sdi, - &analog_sent, analog_todo); + send_analog_packet(value, sdi, &analog_sent, + devc->sent_samples + analog_done, + samples_todo - analog_done); } - analog_todo -= analog_sent; - devc->analog_counter += analog_sent; + analog_done += analog_sent; } } + /* At this point, both logic_done and analog_done should be + * exactly equal to samples_todo, or else. + */ + if (logic_done != samples_todo || analog_done != samples_todo) { + sr_err("BUG: Sample count mismatch."); + return G_SOURCE_REMOVE; + } + devc->sent_samples += samples_todo; + devc->spent_us += todo_us; + + if ((devc->limit_samples > 0 && devc->sent_samples >= devc->limit_samples) + || (limit_us > 0 && devc->spent_us >= limit_us)) { - if (!devc->continuous - && (!devc->num_logic_channels || devc->logic_counter >= devc->limit_samples) - && (!devc->num_analog_channels || devc->analog_counter >= devc->limit_samples)) { /* If we're averaging everything - now is the time to send data */ if (devc->avg_samples == 0) { g_hash_table_iter_init(&iter, devc->ch_ag); @@ -819,13 +840,11 @@ static int prepare_data(int fd, int revents, void *cb_data) sr_session_send(sdi, &packet); } } - sr_dbg("Requested number of samples reached."); - dev_acquisition_stop(sdi, cb_data); - return TRUE; + dev_acquisition_stop(sdi, sdi); } - return TRUE; + return G_SOURCE_CONTINUE; } static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data) @@ -840,8 +859,7 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data) return SR_ERR_DEV_CLOSED; devc = sdi->priv; - devc->continuous = !devc->limit_samples; - devc->logic_counter = devc->analog_counter = 0; + devc->sent_samples = 0; g_hash_table_iter_init(&iter, devc->ch_ag); while (g_hash_table_iter_next(&iter, NULL, &value)) @@ -853,7 +871,8 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data) std_session_send_df_header(sdi, LOG_PREFIX); /* We use this timestamp to decide how many more samples to send. */ - devc->starttime = g_get_monotonic_time(); + devc->start_us = g_get_monotonic_time(); + devc->spent_us = 0; return SR_OK; }