demo: Support changing the amplitude of analog channels.

diff --git a/src/hardware/demo/demo.c b/src/hardware/demo/demo.c
index 11e157ec8a89afd35b00082067bf148579e15e07..7925b5b42f6d0fe719b64554cb51d197d8035ac7 100644 (file)
--- a/src/hardware/demo/demo.c
+++ b/src/hardware/demo/demo.c
@@ -42,7 +42,7 @@
 /* Size of the analog pattern space per channel. */
 #define ANALOG_BUFSIZE       4096
 
-#define ANALOG_AMPLITUDE 25
+#define DEFAULT_ANALOG_AMPLITUDE 25
 #define ANALOG_SAMPLES_PER_PERIOD 20
 
 /* Logic patterns we can generate. */
@@ -99,6 +99,7 @@ static const char *analog_pattern_str[] = {
 
 struct analog_gen {
        int pattern;
+       float amplitude;
        float pattern_data[ANALOG_BUFSIZE];
        unsigned int num_samples;
        struct sr_datafeed_analog packet;
@@ -143,6 +144,7 @@ static const int devopts[] = {
 
 static const int devopts_cg[] = {
        SR_CONF_PATTERN_MODE,
+       SR_CONF_AMPLITUDE,
 };
 
 static const uint64_t samplerates[] = {
@@ -189,7 +191,7 @@ static void generate_analog_pattern(const struct sr_channel_group *cg, uint64_t
 
        switch (ag->pattern) {
        case PATTERN_SQUARE:
-               value = ANALOG_AMPLITUDE;
+               value = ag->amplitude;
                last_end = 0;
                for (i = 0; i < num_samples; i++) {
                        if (i % 5 == 0)
@@ -213,7 +215,7 @@ static void generate_analog_pattern(const struct sr_channel_group *cg, uint64_t
 
                for (i = 0; i < num_samples; i++) {
                        t = (double) i / (double) sample_rate;
-                       ag->pattern_data[i] = ANALOG_AMPLITUDE *
+                       ag->pattern_data[i] = ag->amplitude *
                                                sin(2 * M_PI * frequency * t);
                }
 
@@ -228,7 +230,7 @@ static void generate_analog_pattern(const struct sr_channel_group *cg, uint64_t
 
                for (i = 0; i < num_samples; i++) {
                        t = (double) i / (double) sample_rate;
-                       ag->pattern_data[i] = (2 * ANALOG_AMPLITUDE / M_PI) *
+                       ag->pattern_data[i] = (2 * ag->amplitude / M_PI) *
                                                asin(sin(2 * M_PI * frequency * t));
                }
 
@@ -243,7 +245,7 @@ static void generate_analog_pattern(const struct sr_channel_group *cg, uint64_t
 
                for (i = 0; i < num_samples; i++) {
                        t = (double) i / (double) sample_rate;
-                       ag->pattern_data[i] = 2 * ANALOG_AMPLITUDE *
+                       ag->pattern_data[i] = 2 * ag->amplitude *
                                                ((t * frequency) - floor(0.5f + t * frequency));
                }
 
@@ -338,6 +340,7 @@ static GSList *scan(GSList *options)
                /* Every channel group gets a generator struct. */
                if (!(ag = g_try_malloc(sizeof(struct analog_gen))))
                        return NULL;
+               ag->amplitude = DEFAULT_ANALOG_AMPLITUDE;
                ag->packet.channels = cg->channels;
                ag->packet.mq = 0;
                ag->packet.mqflags = 0;
@@ -442,6 +445,15 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
        case SR_CONF_NUM_ANALOG_CHANNELS:
                *data = g_variant_new_int32(devc->num_analog_channels);
                break;
+       case SR_CONF_AMPLITUDE:
+               if (!cg)
+                       return SR_ERR_CHANNEL_GROUP;
+               ch = cg->channels->data;
+               if (ch->type != SR_CHANNEL_ANALOG)
+                       return SR_ERR_ARG;
+               ag = cg->priv;
+               *data = g_variant_new_double(ag->amplitude);
+               break;
        default:
                return SR_ERR_NA;
        }
@@ -520,6 +532,15 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
                } else
                        return SR_ERR_BUG;
                break;
+       case SR_CONF_AMPLITUDE:
+               if (!cg)
+                       return SR_ERR_CHANNEL_GROUP;
+               ch = cg->channels->data;
+               if (ch->type != SR_CHANNEL_ANALOG)
+                       return SR_ERR_ARG;
+               ag = cg->priv;
+               ag->amplitude = g_variant_get_double(data);
+               break;
        default:
                ret = SR_ERR_NA;
        }