rdtech-dps: Retry sr_modbus_read_holding_registers() up to 3 times.

[libsigrok.git] / src / hardware / rdtech-dps / protocol.c

diff --git a/src/hardware/rdtech-dps/protocol.c b/src/hardware/rdtech-dps/protocol.c
index f01e5742542ea336033d3b789b48f3f762400f9a..fe34b25700184fef2bb0428838a9c76e83eee235 100644 (file)
--- a/src/hardware/rdtech-dps/protocol.c
+++ b/src/hardware/rdtech-dps/protocol.c
@@ -21,6 +21,21 @@
 #include <config.h>
 #include "protocol.h"
 
+SR_PRIV int rdtech_dps_read_holding_registers(struct sr_modbus_dev_inst *modbus,
+               int address, int nb_registers, uint16_t *registers)
+{
+       int i, ret;
+
+       i = 0;
+       do {
+               ret = sr_modbus_read_holding_registers(modbus,
+                       address, nb_registers, registers);
+               ++i;
+       } while (ret != SR_OK && i < 3);
+
+       return ret;
+}
+
 SR_PRIV int rdtech_dps_get_reg(const struct sr_dev_inst *sdi,
                uint16_t address, uint16_t *value)
 {
@@ -33,7 +48,7 @@ SR_PRIV int rdtech_dps_get_reg(const struct sr_dev_inst *sdi,
        modbus = sdi->conn;
 
        g_mutex_lock(&devc->rw_mutex);
-       ret = sr_modbus_read_holding_registers(modbus, address, 1, registers);
+       ret = rdtech_dps_read_holding_registers(modbus, address, 1, registers);
        g_mutex_unlock(&devc->rw_mutex);
        *value = RB16(registers + 0);
        return ret;
@@ -67,7 +82,7 @@ SR_PRIV int rdtech_dps_get_model_version(struct sr_modbus_dev_inst *modbus,
         * No mutex here, because there is no sr_dev_inst when this function
         * is called.
         */
-       ret = sr_modbus_read_holding_registers(modbus, REG_MODEL, 2, registers);
+       ret = rdtech_dps_read_holding_registers(modbus, REG_MODEL, 2, registers);
        if (ret == SR_OK) {
                *model = RB16(registers + 0);
                *version = RB16(registers + 1);
@@ -77,7 +92,8 @@ SR_PRIV int rdtech_dps_get_model_version(struct sr_modbus_dev_inst *modbus,
 }
 
 static void send_value(const struct sr_dev_inst *sdi, struct sr_channel *ch,
-               float value, enum sr_mq mq, enum sr_unit unit, int digits)
+               float value, enum sr_mq mq, enum sr_mqflag mqflags,
+               enum sr_unit unit, int digits)
 {
        struct sr_datafeed_packet packet;
        struct sr_datafeed_analog analog;
@@ -90,8 +106,8 @@ static void send_value(const struct sr_dev_inst *sdi, struct sr_channel *ch,
        analog.num_samples = 1;
        analog.data = &value;
        analog.meaning->mq = mq;
+       analog.meaning->mqflags = mqflags;
        analog.meaning->unit = unit;
-       analog.meaning->mqflags = SR_MQFLAG_DC;
 
        packet.type = SR_DF_ANALOG;
        packet.payload = &analog;
@@ -118,6 +134,10 @@ SR_PRIV int rdtech_dps_receive_data(int fd, int revents, void *cb_data)
        devc = sdi->priv;
 
        g_mutex_lock(&devc->rw_mutex);
+       /*
+        * Using the libsigrok function here, because it doesn't matter if the
+        * reading fails. It will be done again in the next acquision cycle anyways.
+        */
        ret = sr_modbus_read_holding_registers(modbus, REG_UOUT, 3, registers);
        g_mutex_unlock(&devc->rw_mutex);
 
@@ -127,13 +147,13 @@ SR_PRIV int rdtech_dps_receive_data(int fd, int revents, void *cb_data)
 
                send_value(sdi, sdi->channels->data,
                        RB16(registers + 0) / 100.0f,
-                       SR_MQ_VOLTAGE, SR_UNIT_VOLT, 3);
+                       SR_MQ_VOLTAGE, SR_MQFLAG_DC, SR_UNIT_VOLT, 3);
                send_value(sdi, sdi->channels->next->data,
                        RB16(registers + 1) / 1000.0f,
-                       SR_MQ_CURRENT, SR_UNIT_AMPERE, 4);
+                       SR_MQ_CURRENT, SR_MQFLAG_DC, SR_UNIT_AMPERE, 4);
                send_value(sdi, sdi->channels->next->next->data,
                        RB16(registers + 2) / 100.0f,
-                       SR_MQ_POWER, SR_UNIT_WATT, 3);
+                       SR_MQ_POWER, 0, SR_UNIT_WATT, 3);
 
                packet.type = SR_DF_FRAME_END;
                sr_session_send(sdi, &packet);