]> sigrok.org Git - libsigrok.git/blobdiff - hardware/demo/demo.c
Centralise duplicated logging helper defines.
[libsigrok.git] / hardware / demo / demo.c
index e435482e32ac1c91e67aba58c1cfd452255765c9..f5ba2596d06503c012ac62fff7877f5caff4d5bd 100644 (file)
@@ -1,8 +1,9 @@
 /*
- * This file is part of the sigrok project.
+ * This file is part of the libsigrok project.
  *
  * Copyright (C) 2010 Uwe Hermann <uwe@hermann-uwe.de>
  * Copyright (C) 2011 Olivier Fauchon <olivier@aixmarseille.com>
+ * Copyright (C) 2012 Alexandru Gagniuc <mr.nuke.me@gmail.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
 #include "libsigrok.h"
 #include "libsigrok-internal.h"
 
-/* TODO: Number of probes should be configurable. */
-#define NUM_PROBES             8
+#define LOG_PREFIX "demo"
 
-#define DEMONAME               "Demo device"
+/* TODO: Number of probes should be configurable. */
+#define NUM_PROBES           8
 
 /* The size of chunks to send through the session bus. */
 /* TODO: Should be configurable. */
-#define BUFSIZE                4096
+#define LOGIC_BUFSIZE        4096
 
-/* Supported patterns which we can generate */
+/* Patterns we can generate */
 enum {
        /**
-        * Pattern which spells "sigrok" using '0's (with '1's as "background")
-        * when displayed using the 'bits' output format.
+        * Spells "sigrok" across 8 probes using '0's (with '1's as
+        * "background") when displayed using the 'bits' output format.
         */
        PATTERN_SIGROK,
 
-       /** Pattern which consists of (pseudo-)random values on all probes. */
+       /** Pseudo-)random values on all probes. */
        PATTERN_RANDOM,
 
        /**
-        * Pattern which consists of incrementing numbers.
-        * TODO: Better description.
+        * Incrementing number across all probes.
         */
        PATTERN_INC,
 
-       /** Pattern where all probes have a low logic state. */
+       /** All probes have a low logic state. */
        PATTERN_ALL_LOW,
 
-       /** Pattern where all probes have a high logic state. */
+       /** All probes have a high logic state. */
        PATTERN_ALL_HIGH,
 };
 
+static const char *pattern_strings[] = {
+       "sigrok",
+       "random",
+       "incremental",
+       "all-low",
+       "all-high",
+};
+
 /* Private, per-device-instance driver context. */
 struct dev_context {
        int pipe_fds[2];
-       GIOChannel *channels[2];
+       GIOChannel *channel;
+       uint64_t cur_samplerate;
+       uint64_t limit_samples;
+       uint64_t limit_msec;
        uint8_t sample_generator;
-       uint8_t thread_running;
        uint64_t samples_counter;
-       void *session_dev_id;
-       GTimer *timer;
+       void *cb_data;
+       int64_t starttime;
+       unsigned char logic_data[LOGIC_BUFSIZE];
+       uint64_t step;
 };
 
 static const int hwcaps[] = {
-       SR_HWCAP_LOGIC_ANALYZER,
-       SR_HWCAP_DEMO_DEV,
-       SR_HWCAP_SAMPLERATE,
-       SR_HWCAP_PATTERN_MODE,
-       SR_HWCAP_LIMIT_SAMPLES,
-       SR_HWCAP_LIMIT_MSEC,
-       SR_HWCAP_CONTINUOUS,
+       SR_CONF_LOGIC_ANALYZER,
+       SR_CONF_DEMO_DEV,
+       SR_CONF_SAMPLERATE,
+       SR_CONF_PATTERN_MODE,
+       SR_CONF_LIMIT_SAMPLES,
+       SR_CONF_LIMIT_MSEC,
+       SR_CONF_CONTINUOUS,
 };
 
-static const struct sr_samplerates samplerates = {
+static const uint64_t samplerates[] = {
        SR_HZ(1),
        SR_GHZ(1),
        SR_HZ(1),
-       NULL,
-};
-
-static const char *pattern_strings[] = {
-       "sigrok",
-       "random",
-       "incremental",
-       "all-low",
-       "all-high",
-       NULL,
-};
-
-/* We name the probes 0-7 on our demo driver. */
-static const char *probe_names[NUM_PROBES + 1] = {
-       "0",
-       "1",
-       "2",
-       "3",
-       "4",
-       "5",
-       "6",
-       "7",
-       NULL,
 };
 
 static uint8_t pattern_sigrok[] = {
@@ -129,52 +118,46 @@ static uint8_t pattern_sigrok[] = {
 
 /* List of struct sr_dev_inst, maintained by dev_open()/dev_close(). */
 SR_PRIV struct sr_dev_driver demo_driver_info;
-static struct sr_dev_driver *ddi = &demo_driver_info;
-static uint64_t cur_samplerate = SR_KHZ(200);
-static uint64_t limit_samples = 0;
-static uint64_t limit_msec = 0;
-static int default_pattern = PATTERN_SIGROK;
-static GThread *my_thread;
-static int thread_running;
-
-static int hw_dev_acquisition_stop(const struct sr_dev_inst *sdi,
-               void *cb_data);
-
-static int hw_init(void)
-{
-       struct drv_context *drvc;
+static struct sr_dev_driver *di = &demo_driver_info;
 
-       if (!(drvc = g_try_malloc0(sizeof(struct drv_context)))) {
-               sr_err("fx2lafw: driver context malloc failed.");
-               return SR_ERR;
-       }
-       ddi->priv = drvc;
+static int dev_acquisition_stop(struct sr_dev_inst *sdi, void *cb_data);
 
-       return SR_OK;
+static int dev_clear(void)
+{
+       return std_dev_clear(di, NULL);
+}
+
+static int init(struct sr_context *sr_ctx)
+{
+       return std_init(sr_ctx, di, LOG_PREFIX);
 }
 
-static GSList *hw_scan(GSList *options)
+static GSList *scan(GSList *options)
 {
        struct sr_dev_inst *sdi;
        struct sr_probe *probe;
        struct drv_context *drvc;
+       struct dev_context *devc;
        GSList *devices;
        int i;
+       char probe_name[16];
 
        (void)options;
-       drvc = ddi->priv;
+
+       drvc = di->priv;
+
        devices = NULL;
 
-       sdi = sr_dev_inst_new(0, SR_ST_ACTIVE, DEMONAME, NULL, NULL);
+       sdi = sr_dev_inst_new(0, SR_ST_ACTIVE, "Demo device", NULL, NULL);
        if (!sdi) {
-               sr_err("demo: %s: sr_dev_inst_new failed", __func__);
-               return 0;
+               sr_err("Device instance creation failed.");
+               return NULL;
        }
-       sdi->driver = ddi;
+       sdi->driver = di;
 
-       for (i = 0; probe_names[i]; i++) {
-               if (!(probe = sr_probe_new(i, SR_PROBE_ANALOG, TRUE,
-                               probe_names[i])))
+       for (i = 0; i < NUM_PROBES; i++) {
+               sprintf(probe_name, "D%d", i);
+               if (!(probe = sr_probe_new(i, SR_PROBE_LOGIC, TRUE, probe_name)))
                        return NULL;
                sdi->probes = g_slist_append(sdi->probes, probe);
        }
@@ -182,352 +165,300 @@ static GSList *hw_scan(GSList *options)
        devices = g_slist_append(devices, sdi);
        drvc->instances = g_slist_append(drvc->instances, sdi);
 
-       return devices;
-}
+       if (!(devc = g_try_malloc(sizeof(struct dev_context)))) {
+               sr_err("Device context malloc failed.");
+               return NULL;
+       }
 
-static GSList *hw_dev_list(void)
-{
-       struct drv_context *drvc;
+       devc->cur_samplerate = SR_KHZ(200);
+       devc->limit_samples = 0;
+       devc->limit_msec = 0;
+       devc->sample_generator = PATTERN_SIGROK;
+       devc->step =0;
 
-       drvc = ddi->priv;
+       sdi->priv = devc;
 
-       return drvc->instances;
+       return devices;
 }
 
-static int hw_dev_open(struct sr_dev_inst *sdi)
+static GSList *dev_list(void)
 {
-       /* Avoid compiler warnings. */
-       (void)sdi;
+       return ((struct drv_context *)(di->priv))->instances;
+}
 
-       /* Nothing needed so far. */
+static int dev_open(struct sr_dev_inst *sdi)
+{
+       sdi->status = SR_ST_ACTIVE;
 
        return SR_OK;
 }
 
-static int hw_dev_close(struct sr_dev_inst *sdi)
+static int dev_close(struct sr_dev_inst *sdi)
 {
-       /* Avoid compiler warnings. */
-       (void)sdi;
-
-       /* Nothing needed so far. */
+       sdi->status = SR_ST_INACTIVE;
 
        return SR_OK;
 }
 
-static int hw_cleanup(void)
+static int cleanup(void)
 {
-       /* Nothing needed so far. */
-       return SR_OK;
+       return dev_clear();
 }
 
-static int hw_info_get(int info_id, const void **data,
-       const struct sr_dev_inst *sdi)
+static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
+               const struct sr_probe_group *probe_group)
 {
+       struct dev_context *const devc = sdi->priv;
 
-       (void)sdi;
+       (void)probe_group;
 
-       switch (info_id) {
-       case SR_DI_HWCAPS:
-               *data = hwcaps;
-               break;
-       case SR_DI_NUM_PROBES:
-               *data = GINT_TO_POINTER(NUM_PROBES);
-               break;
-       case SR_DI_PROBE_NAMES:
-               *data = probe_names;
+       switch (id) {
+       case SR_CONF_SAMPLERATE:
+               *data = g_variant_new_uint64(devc->cur_samplerate);
                break;
-       case SR_DI_SAMPLERATES:
-               *data = &samplerates;
+       case SR_CONF_LIMIT_SAMPLES:
+               *data = g_variant_new_uint64(devc->limit_samples);
                break;
-       case SR_DI_CUR_SAMPLERATE:
-               *data = &cur_samplerate;
+       case SR_CONF_LIMIT_MSEC:
+               *data = g_variant_new_uint64(devc->limit_msec);
                break;
-       case SR_DI_PATTERNS:
-               *data = &pattern_strings;
+       case SR_CONF_PATTERN_MODE:
+               *data = g_variant_new_string(pattern_strings[devc->sample_generator]);
                break;
        default:
-               return SR_ERR_ARG;
+               return SR_ERR_NA;
        }
 
        return SR_OK;
 }
 
-static int hw_dev_config_set(const struct sr_dev_inst *sdi, int hwcap,
-               const void *value)
+static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+               const struct sr_probe_group *probe_group)
 {
+       unsigned int i;
        int ret;
        const char *stropt;
 
-       (void)sdi;
+       (void)probe_group;
+       struct dev_context *const devc = sdi->priv;
 
-       if (hwcap == SR_HWCAP_SAMPLERATE) {
-               cur_samplerate = *(const uint64_t *)value;
-               sr_dbg("demo: %s: setting samplerate to %" PRIu64, __func__,
-                      cur_samplerate);
-               ret = SR_OK;
-       } else if (hwcap == SR_HWCAP_LIMIT_SAMPLES) {
-               limit_msec = 0;
-               limit_samples = *(const uint64_t *)value;
-               sr_dbg("demo: %s: setting limit_samples to %" PRIu64, __func__,
-                      limit_samples);
+       if (sdi->status != SR_ST_ACTIVE)
+               return SR_ERR_DEV_CLOSED;
+
+       if (id == SR_CONF_SAMPLERATE) {
+               devc->cur_samplerate = g_variant_get_uint64(data);
+               sr_dbg("Setting samplerate to %" PRIu64, devc->cur_samplerate);
                ret = SR_OK;
-       } else if (hwcap == SR_HWCAP_LIMIT_MSEC) {
-               limit_msec = *(const uint64_t *)value;
-               limit_samples = 0;
-               sr_dbg("demo: %s: setting limit_msec to %" PRIu64, __func__,
-                      limit_msec);
+       } else if (id == SR_CONF_LIMIT_SAMPLES) {
+               devc->limit_msec = 0;
+               devc->limit_samples = g_variant_get_uint64(data);
+               sr_dbg("Setting limit_samples to %" PRIu64, devc->limit_samples);
                ret = SR_OK;
-       } else if (hwcap == SR_HWCAP_PATTERN_MODE) {
-               stropt = value;
+       } else if (id == SR_CONF_LIMIT_MSEC) {
+               devc->limit_msec = g_variant_get_uint64(data);
+               devc->limit_samples = 0;
+               sr_dbg("Setting limit_msec to %" PRIu64, devc->limit_msec);
                ret = SR_OK;
-               if (!strcmp(stropt, "sigrok")) {
-                       default_pattern = PATTERN_SIGROK;
-               } else if (!strcmp(stropt, "random")) {
-                       default_pattern = PATTERN_RANDOM;
-               } else if (!strcmp(stropt, "incremental")) {
-                       default_pattern = PATTERN_INC;
-               } else if (!strcmp(stropt, "all-low")) {
-                       default_pattern = PATTERN_ALL_LOW;
-               } else if (!strcmp(stropt, "all-high")) {
-                       default_pattern = PATTERN_ALL_HIGH;
-               } else {
-                       ret = SR_ERR;
+       } else if (id == SR_CONF_PATTERN_MODE) {
+               stropt = g_variant_get_string(data, NULL);
+               ret = SR_ERR;
+               for (i = 0; i < ARRAY_SIZE(pattern_strings); i++) {
+                       if (!strcmp(stropt, pattern_strings[i])) {
+                               devc->sample_generator = i;
+                               ret = SR_OK;
+                               break;
+                       }
                }
-               sr_dbg("demo: %s: setting pattern to %d", __func__,
-                      default_pattern);
+               /* Might as well do this now. */
+               if (i == PATTERN_ALL_LOW)
+                       memset(devc->logic_data, 0x00, LOGIC_BUFSIZE);
+               else if (i == PATTERN_ALL_HIGH)
+                       memset(devc->logic_data, 0xff, LOGIC_BUFSIZE);
+               sr_dbg("Setting pattern to %s", pattern_strings[i]);
        } else {
-               ret = SR_ERR;
+               ret = SR_ERR_NA;
        }
 
        return ret;
 }
 
-static void samples_generator(uint8_t *buf, uint64_t size, void *data)
+static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+               const struct sr_probe_group *probe_group)
 {
-       static uint64_t p = 0;
-       struct dev_context *devc = data;
+       GVariant *gvar;
+       GVariantBuilder gvb;
+
+       (void)sdi;
+       (void)probe_group;
+
+       switch (key) {
+       case SR_CONF_DEVICE_OPTIONS:
+               *data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
+                               hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+               break;
+       case SR_CONF_SAMPLERATE:
+               g_variant_builder_init(&gvb, G_VARIANT_TYPE("a{sv}"));
+               gvar = g_variant_new_fixed_array(G_VARIANT_TYPE("t"), samplerates,
+                               ARRAY_SIZE(samplerates), sizeof(uint64_t));
+               g_variant_builder_add(&gvb, "{sv}", "samplerate-steps", gvar);
+               *data = g_variant_builder_end(&gvb);
+               break;
+       case SR_CONF_PATTERN_MODE:
+               *data = g_variant_new_strv(pattern_strings, ARRAY_SIZE(pattern_strings));
+               break;
+       default:
+               return SR_ERR_NA;
+       }
+
+       return SR_OK;
+}
+
+static void sample_generator(struct sr_dev_inst *sdi, uint64_t size)
+{
+       struct dev_context *devc;
        uint64_t i;
 
-       /* TODO: Needed? */
-       memset(buf, 0, size);
+       devc = sdi->priv;
 
        switch (devc->sample_generator) {
-       case PATTERN_SIGROK: /* sigrok pattern */
+       case PATTERN_SIGROK:
                for (i = 0; i < size; i++) {
-                       *(buf + i) = ~(pattern_sigrok[p] >> 1);
-                       if (++p == 64)
-                               p = 0;
+                       devc->logic_data[i] = ~(pattern_sigrok[
+                               devc->step++ % sizeof(pattern_sigrok)] >> 1);
                }
                break;
-       case PATTERN_RANDOM: /* Random */
+       case PATTERN_RANDOM:
                for (i = 0; i < size; i++)
-                       *(buf + i) = (uint8_t)(rand() & 0xff);
+                       devc->logic_data[i] = (uint8_t)(rand() & 0xff);
                break;
-       case PATTERN_INC: /* Simple increment */
+       case PATTERN_INC:
                for (i = 0; i < size; i++)
-                       *(buf + i) = i;
+                       devc->logic_data[i] = devc->step++;
                break;
-       case PATTERN_ALL_LOW: /* All probes are low */
-               memset(buf, 0x00, size);
-               break;
-       case PATTERN_ALL_HIGH: /* All probes are high */
-               memset(buf, 0xff, size);
+       case PATTERN_ALL_LOW:
+       case PATTERN_ALL_HIGH:
+               /* These were set when the pattern mode was selected. */
                break;
        default:
-               sr_err("demo: %s: unknown pattern %d", __func__,
-                      devc->sample_generator);
+               sr_err("Unknown pattern: %d.", devc->sample_generator);
                break;
        }
 }
 
-/* Thread function */
-static void thread_func(void *data)
-{
-       struct dev_context *devc = data;
-       uint8_t buf[BUFSIZE];
-       uint64_t nb_to_send = 0;
-       int bytes_written;
-       double time_cur, time_last, time_diff;
-
-       time_last = g_timer_elapsed(devc->timer, NULL);
-
-       while (thread_running) {
-               /* Rate control */
-               time_cur = g_timer_elapsed(devc->timer, NULL);
-
-               time_diff = time_cur - time_last;
-               time_last = time_cur;
-
-               nb_to_send = cur_samplerate * time_diff;
-
-               if (limit_samples) {
-                       nb_to_send = MIN(nb_to_send,
-                                     limit_samples - devc->samples_counter);
-               }
-
-               /* Make sure we don't overflow. */
-               nb_to_send = MIN(nb_to_send, BUFSIZE);
-
-               if (nb_to_send) {
-                       samples_generator(buf, nb_to_send, data);
-                       devc->samples_counter += nb_to_send;
-
-                       g_io_channel_write_chars(devc->channels[1], (gchar *)&buf,
-                               nb_to_send, (gsize *)&bytes_written, NULL);
-               }
-
-               /* Check if we're done. */
-               if ((limit_msec && time_cur * 1000 > limit_msec) ||
-                   (limit_samples && devc->samples_counter >= limit_samples))
-               {
-                       close(devc->pipe_fds[1]);
-                       thread_running = 0;
-               }
-
-               g_usleep(10);
-       }
-}
-
 /* Callback handling data */
-static int receive_data(int fd, int revents, void *cb_data)
+static int prepare_data(int fd, int revents, void *cb_data)
 {
-       struct dev_context *devc = cb_data;
+       struct sr_dev_inst *sdi;
+       struct dev_context *devc;
        struct sr_datafeed_packet packet;
        struct sr_datafeed_logic logic;
-       static uint64_t samples_received = 0;
-       unsigned char c[BUFSIZE];
-       gsize z;
+       static uint64_t samples_to_send, expected_samplenum, sending_now;
+       int64_t time, elapsed;
 
-       /* Avoid compiler warnings. */
        (void)fd;
        (void)revents;
 
-       do {
-               g_io_channel_read_chars(devc->channels[0],
-                                       (gchar *)&c, BUFSIZE, &z, NULL);
-
-               if (z > 0) {
-                       packet.type = SR_DF_LOGIC;
-                       packet.payload = &logic;
-                       logic.length = z;
-                       logic.unitsize = 1;
-                       logic.data = c;
-                       sr_session_send(devc->session_dev_id, &packet);
-                       samples_received += z;
-               }
-       } while (z > 0);
+       sdi = cb_data;
+       devc = sdi->priv;
+
+       /* How many "virtual" samples should we have collected by now? */
+       time = g_get_monotonic_time();
+       elapsed = time - devc->starttime;
+       expected_samplenum = elapsed * devc->cur_samplerate / 1000000;
+       /* Of those, how many do we still have to send? */
+       samples_to_send = expected_samplenum - devc->samples_counter;
 
-       if (!thread_running && z <= 0) {
-               /* Make sure we don't receive more packets. */
-               g_io_channel_shutdown(devc->channels[0], FALSE, NULL);
+       if (devc->limit_samples) {
+               samples_to_send = MIN(samples_to_send,
+                                devc->limit_samples - devc->samples_counter);
+       }
 
-               /* Send last packet. */
-               packet.type = SR_DF_END;
-               sr_session_send(devc->session_dev_id, &packet);
+       while (samples_to_send > 0) {
+               sending_now = MIN(samples_to_send, LOGIC_BUFSIZE);
+               samples_to_send -= sending_now;
+               sample_generator(sdi, sending_now);
+
+               packet.type = SR_DF_LOGIC;
+               packet.payload = &logic;
+               logic.length = sending_now;
+               logic.unitsize = 1;
+               logic.data = devc->logic_data;
+               sr_session_send(devc->cb_data, &packet);
+               devc->samples_counter += sending_now;
+       }
 
-               return FALSE;
+       if (devc->limit_samples &&
+               devc->samples_counter >= devc->limit_samples) {
+               sr_info("Requested number of samples reached.");
+               dev_acquisition_stop(sdi, cb_data);
+               return TRUE;
        }
 
        return TRUE;
 }
 
-static int hw_dev_acquisition_start(const struct sr_dev_inst *sdi,
-               void *cb_data)
+static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 {
-       struct sr_datafeed_packet *packet;
-       struct sr_datafeed_header *header;
-       struct sr_datafeed_meta_logic meta;
        struct dev_context *devc;
 
-       (void)sdi;
-
-       /* TODO: 'devc' is never g_free()'d? */
-       if (!(devc = g_try_malloc(sizeof(struct dev_context)))) {
-               sr_err("demo: %s: devc malloc failed", __func__);
-               return SR_ERR_MALLOC;
-       }
+       if (sdi->status != SR_ST_ACTIVE)
+               return SR_ERR_DEV_CLOSED;
 
-       devc->sample_generator = default_pattern;
-       devc->session_dev_id = cb_data;
+       devc = sdi->priv;
+       devc->cb_data = cb_data;
        devc->samples_counter = 0;
 
+       /*
+        * Setting two channels connected by a pipe is a remnant from when the
+        * demo driver generated data in a thread, and collected and sent the
+        * data in the main program loop.
+        * They are kept here because it provides a convenient way of setting
+        * up a timeout-based polling mechanism.
+        */
        if (pipe(devc->pipe_fds)) {
-               /* TODO: Better error message. */
-               sr_err("demo: %s: pipe() failed", __func__);
+               sr_err("%s: pipe() failed", __func__);
                return SR_ERR;
        }
 
-       devc->channels[0] = g_io_channel_unix_new(devc->pipe_fds[0]);
-       devc->channels[1] = g_io_channel_unix_new(devc->pipe_fds[1]);
+       devc->channel = g_io_channel_unix_new(devc->pipe_fds[0]);
 
-       g_io_channel_set_flags(devc->channels[0], G_IO_FLAG_NONBLOCK, NULL);
+       g_io_channel_set_flags(devc->channel, G_IO_FLAG_NONBLOCK, NULL);
 
        /* Set channel encoding to binary (default is UTF-8). */
-       g_io_channel_set_encoding(devc->channels[0], NULL, NULL);
-       g_io_channel_set_encoding(devc->channels[1], NULL, NULL);
+       g_io_channel_set_encoding(devc->channel, NULL, NULL);
 
        /* Make channels to unbuffered. */
-       g_io_channel_set_buffered(devc->channels[0], FALSE);
-       g_io_channel_set_buffered(devc->channels[1], FALSE);
-
-       sr_session_source_add_channel(devc->channels[0], G_IO_IN | G_IO_ERR,
-                   40, receive_data, devc);
-
-       /* Run the demo thread. */
-       g_thread_init(NULL);
-       /* This must to be done between g_thread_init() & g_thread_create(). */
-       devc->timer = g_timer_new();
-       thread_running = 1;
-       my_thread =
-           g_thread_create((GThreadFunc)thread_func, devc, TRUE, NULL);
-       if (!my_thread) {
-               sr_err("demo: %s: g_thread_create failed", __func__);
-               return SR_ERR; /* TODO */
-       }
+       g_io_channel_set_buffered(devc->channel, FALSE);
 
-       if (!(packet = g_try_malloc(sizeof(struct sr_datafeed_packet)))) {
-               sr_err("demo: %s: packet malloc failed", __func__);
-               return SR_ERR_MALLOC;
-       }
+       sr_session_source_add_channel(devc->channel, G_IO_IN | G_IO_ERR,
+                       40, prepare_data, (void *)sdi);
 
-       if (!(header = g_try_malloc(sizeof(struct sr_datafeed_header)))) {
-               sr_err("demo: %s: header malloc failed", __func__);
-               return SR_ERR_MALLOC;
-       }
-
-       packet->type = SR_DF_HEADER;
-       packet->payload = header;
-       header->feed_version = 1;
-       gettimeofday(&header->starttime, NULL);
-       sr_session_send(devc->session_dev_id, packet);
-
-       /* Send metadata about the SR_DF_LOGIC packets to come. */
-       packet->type = SR_DF_META_LOGIC;
-       packet->payload = &meta;
-       meta.samplerate = cur_samplerate;
-       meta.num_probes = NUM_PROBES;
-       sr_session_send(devc->session_dev_id, packet);
+       /* Send header packet to the session bus. */
+       std_session_send_df_header(cb_data, LOG_PREFIX);
 
-       g_free(header);
-       g_free(packet);
+       /* We use this timestamp to decide how many more samples to send. */
+       devc->starttime = g_get_monotonic_time();
 
        return SR_OK;
 }
 
-static int hw_dev_acquisition_stop(const struct sr_dev_inst *sdi,
-               void *cb_data)
+static int dev_acquisition_stop(struct sr_dev_inst *sdi, void *cb_data)
 {
-       struct dev_context *devc;
+       struct dev_context *const devc = sdi->priv;
+       struct sr_datafeed_packet packet;
 
-       /* Avoid compiler warnings. */
        (void)cb_data;
 
-       devc = sdi->priv;
+       sr_dbg("Stopping aquisition.");
 
-       /* Stop generate thread. */
-       thread_running = 0;
+       sr_session_source_remove_channel(devc->channel);
+       g_io_channel_shutdown(devc->channel, FALSE, NULL);
+       g_io_channel_unref(devc->channel);
+       devc->channel = NULL;
 
-       sr_session_source_remove_channel(devc->channels[0]);
+       /* Send last packet. */
+       packet.type = SR_DF_END;
+       sr_session_send(devc->cb_data, &packet);
 
        return SR_OK;
 }
@@ -536,15 +467,17 @@ SR_PRIV struct sr_dev_driver demo_driver_info = {
        .name = "demo",
        .longname = "Demo driver and pattern generator",
        .api_version = 1,
-       .init = hw_init,
-       .cleanup = hw_cleanup,
-       .scan = hw_scan,
-       .dev_list = hw_dev_list,
-       .dev_open = hw_dev_open,
-       .dev_close = hw_dev_close,
-       .info_get = hw_info_get,
-       .dev_config_set = hw_dev_config_set,
-       .dev_acquisition_start = hw_dev_acquisition_start,
-       .dev_acquisition_stop = hw_dev_acquisition_stop,
+       .init = init,
+       .cleanup = cleanup,
+       .scan = scan,
+       .dev_list = dev_list,
+       .dev_clear = dev_clear,
+       .config_get = config_get,
+       .config_set = config_set,
+       .config_list = config_list,
+       .dev_open = dev_open,
+       .dev_close = dev_close,
+       .dev_acquisition_start = dev_acquisition_start,
+       .dev_acquisition_stop = dev_acquisition_stop,
        .priv = NULL,
 };