scpi-pps: Add basic cross-vendor PPS functionality.

[libsigrok.git] / src / hardware / scpi-pps / protocol.c

diff --git a/src/hardware/scpi-pps/protocol.c b/src/hardware/scpi-pps/protocol.c
index 1572a3eadd06e9ce3fe9f709c421007c5b7f6334..b6049dc3f75c925e141db3e46c2e1924b3244c6d 100644 (file)
--- a/src/hardware/scpi-pps/protocol.c
+++ b/src/hardware/scpi-pps/protocol.c
@@ -17,14 +17,52 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <string.h>
+#include <stdarg.h>
 #include "protocol.h"
 
+SR_PRIV int scpi_cmd(const struct sr_dev_inst *sdi, int command, ...)
+{
+       va_list args;
+       struct dev_context *devc;
+       struct sr_scpi_dev_inst *scpi;
+       unsigned int i;
+       int ret;
+       char *cmd;
+
+       devc = sdi->priv;
+       cmd = NULL;
+       for (i = 0; i < devc->device->num_commands; i++) {
+               if (devc->device->commands[i].command == command) {
+                       cmd = devc->device->commands[i].string;
+                       break;
+               }
+       }
+       if (!cmd) {
+               /* Device does not implement this command, that's OK. */
+               return SR_OK_CONTINUE;
+       }
+
+       scpi = sdi->conn;
+       va_start(args, command);
+       ret = sr_scpi_send_variadic(scpi, cmd, args);
+       va_end(args);
+
+       return ret;
+}
+
 SR_PRIV int scpi_pps_receive_data(int fd, int revents, void *cb_data)
 {
-       const struct sr_dev_inst *sdi;
        struct dev_context *devc;
+       struct sr_datafeed_packet packet;
+       struct sr_datafeed_analog analog;
+       const struct sr_dev_inst *sdi;
+       struct sr_scpi_dev_inst *scpi;
+       GSList *l;
+       float f;
 
        (void)fd;
+       (void)revents;
 
        if (!(sdi = cb_data))
                return TRUE;
@@ -32,8 +70,50 @@ SR_PRIV int scpi_pps_receive_data(int fd, int revents, void *cb_data)
        if (!(devc = sdi->priv))
                return TRUE;
 
-       if (revents == G_IO_IN) {
-               /* TODO */
+       if (devc->state == STATE_STOP)
+               return TRUE;
+
+       scpi = sdi->conn;
+
+       /* Retrieve requested value for this state. */
+       if (sr_scpi_get_float(scpi, NULL, &f) == SR_OK) {
+               packet.type = SR_DF_ANALOG;
+               packet.payload = &analog;
+               analog.channels = g_slist_append(NULL, devc->cur_channel);
+               analog.num_samples = 1;
+               if (devc->state == STATE_VOLTAGE) {
+                       analog.mq = SR_MQ_VOLTAGE;
+                       analog.unit = SR_UNIT_VOLT;
+               } else {
+                       analog.mq = SR_MQ_CURRENT;
+                       analog.unit = SR_UNIT_AMPERE;
+               }
+               analog.mqflags = SR_MQFLAG_DC;
+               analog.data = &f;
+               sr_session_send(sdi, &packet);
+               g_slist_free(analog.channels);
+       }
+
+       if (devc->state == STATE_VOLTAGE) {
+               /* Just got voltage, request current for this channel. */
+               devc->state = STATE_CURRENT;
+               scpi_cmd(sdi, SCPI_CMD_GET_MEAS_CURRENT, devc->cur_channel->name);
+       } else if (devc->state == STATE_CURRENT) {
+               /*
+                * Done with voltage and current for this channel, switch to
+                * the next enabled channel.
+                */
+               do {
+                       l = g_slist_find(sdi->channels, devc->cur_channel);
+                       if (l->next)
+                               devc->cur_channel = l->next->data;
+                       else
+                               devc->cur_channel = sdi->channels->data;
+               } while (!devc->cur_channel->enabled);
+
+               /* Request voltage. */
+               devc->state = STATE_VOLTAGE;
+               scpi_cmd(sdi, SCPI_CMD_GET_MEAS_VOLTAGE, devc->cur_channel->name);
        }
 
        return TRUE;