hameg-hmo: Use the host's endianess to read analog channel data via SCPI

Configure the scope to the host's native endianess before downloading
acquisition data from analog channels. This unbreaks operation on those
models which default to a representation which differs from the host.

src/hardware/hameg-hmo/api.c

@@ -568,6 +568,11 @@ SR_PRIV int hmo_request_data(const struct sr_dev_inst *sdi)
 	case SR_CHANNEL_ANALOG:
 		g_snprintf(command, sizeof(command),
 			   (*model->scpi_dialect)[SCPI_CMD_GET_ANALOG_DATA],
+#ifdef WORDS_BIGENDIAN
+			   "MSBF",
+#else
+			   "LSBF",
+#endif
 			   ch->index + 1);
 		break;
 	case SR_CHANNEL_LOGIC:

src/hardware/hameg-hmo/protocol.c

@@ -31,7 +31,8 @@ static const char *hameg_scpi_dialect[] = {
 	[SCPI_CMD_SET_COUPLING]		    = ":CHAN%d:COUP %s",
 	[SCPI_CMD_GET_SAMPLE_RATE]	    = ":ACQ:SRAT?",
 	[SCPI_CMD_GET_SAMPLE_RATE_LIVE]	    = ":%s:DATA:POINTS?",
-	[SCPI_CMD_GET_ANALOG_DATA]	    = ":FORM REAL,32;:CHAN%d:DATA?",
+	[SCPI_CMD_GET_ANALOG_DATA]	    = ":FORM:BORD %s;" \
+					      ":FORM REAL,32;:CHAN%d:DATA?",
 	[SCPI_CMD_GET_VERTICAL_DIV]	    = ":CHAN%d:SCAL?",
 	[SCPI_CMD_SET_VERTICAL_DIV]	    = ":CHAN%d:SCAL %s",
 	[SCPI_CMD_GET_DIG_POD_STATE]	    = ":POD%d:STAT?",
@@ -821,7 +822,11 @@ SR_PRIV int hmo_receive_data(int fd, int revents, void *cb_data)
 		encoding.unitsize = sizeof(float);
 		encoding.is_signed = TRUE;
 		encoding.is_float = TRUE;
+#ifdef WORDS_BIGENDIAN
+		encoding.is_bigendian = TRUE;
+#else
 		encoding.is_bigendian = FALSE;
+#endif
 		/* TODO: Use proper 'digits' value for this device (and its modes). */
 		encoding.digits = 2;
 		encoding.is_digits_decimal = FALSE;

src/hardware/hameg-hmo/protocol.h

@@ -29,7 +29,7 @@
 #define LOG_PREFIX "hameg-hmo"
 
 #define MAX_INSTRUMENT_VERSIONS 10
-#define MAX_COMMAND_SIZE 31
+#define MAX_COMMAND_SIZE 48
 
 struct scope_config {
 	const char *name[MAX_INSTRUMENT_VERSIONS];