controllers: support doubles in write_general and write_channel.

Since these functions are proxies for the RegisterDecoder ones, they
should have had the same type for their value arguments.

This required some fixes to decode-reg where implicit conversion to the
variant wasn't available.

Fixes: d859702

app/decode-reg.cc

@@ -285,17 +285,17 @@ int main(int argc, char *argv[])
         auto channel = args.get<unsigned>("-c");
 
         ctl.write_channel("AMP_EN", channel, args.is_used("-e"));
-        ctl.write_channel("MODE", channel, get_index(args.get<std::string>("-m"), lamp::mode_list));
-        ctl.write_channel("PI_KP", channel, args.get<unsigned>("-k"));
-        ctl.write_channel("PI_TI", channel, args.get<unsigned>("-t"));
+        ctl.write_channel("MODE", channel, (int32_t)get_index(args.get<std::string>("-m"), lamp::mode_list));
+        ctl.write_channel("PI_KP", channel, (int32_t)args.get<unsigned>("-k"));
+        ctl.write_channel("PI_TI", channel, (int32_t)args.get<unsigned>("-t"));
         ctl.write_channel("PI_SP", channel, args.get<int>("-s"));
 
         ctl.write_channel("DAC", channel, args.get<int>("-d"));
         ctl.write_channel("LIMIT_A", channel, args.get<int>("-l"));
         ctl.write_channel("LIMIT_B", channel, args.get<int>("-L"));
         ctl.write_channel("CNT", channel, args.get<int>("-C"));
 
-        ctl.write_channel("TRIG_EN", channel, args.get<unsigned>("-T"));
+        ctl.write_channel("TRIG_EN", channel, (int32_t)args.get<unsigned>("-T"));
 
         ctl.write_params();
     }

util/controllers.h

@@ -51,11 +51,11 @@ class RegisterDecoderController: public RegisterController {
 
     virtual void encode_params() override { }
 
-    void write_general(const char *name, int32_t value)
+    void write_general(const char *name, decoders::data_type value)
     {
         pdec->write_general(name, value, read_dest);
     }
-    void write_channel(const char *name, unsigned pos, int32_t value)
+    void write_channel(const char *name, unsigned pos, decoders::data_type value)
     {
         pdec->write_channel(name, pos, value, read_dest);
     }

util/tests/controllers-test.cc

@@ -44,7 +44,7 @@ TEST_CASE("RegisterDecoderController write_general", "[controllers-test]")
     CHECK(dec.get_general_data<int32_t>("RF_INT") == -0x11);
 }
 
-TEST_CASE("RegisterDecoderController write_general fixed-point", "[controllers-test][!shouldfail]")
+TEST_CASE("RegisterDecoderController write_general fixed-point", "[controllers-test]")
 {
     TestRegisterDecoderController ctl{};
     TestRegisterDecoder dec{};