Added flow control to serial configuration to support xon/xoff for link-mso19

[libsigrok.git] / hardware / common / serial.c

diff --git a/hardware/common/serial.c b/hardware/common/serial.c
index a18ad0b494073962f1bc7fb182b4e1c95db3b2e3..e114f2d0400d175a30283f5b979403b033974c61 100644 (file)
--- a/hardware/common/serial.c
+++ b/hardware/common/serial.c
@@ -278,14 +278,6 @@ SR_PRIV int serial_read(struct sr_serial_dev_inst *serial, void *buf,
 #else
        /* Returns the number of bytes read, or -1 upon failure. */
        ret = read(serial->fd, buf, count);
-       if (ret < 0)
-               /*
-                * Should be sr_err(), but that would yield lots of
-                * "Resource temporarily unavailable" messages.
-                */
-               sr_spew("Read error: %s (fd %d).", strerror(errno), serial->fd);
-       else
-               sr_spew("Read %d/%d bytes (fd %d).", ret, count, serial->fd);
 #endif
 
        return ret;
@@ -639,8 +631,8 @@ SR_PRIV int serial_set_params(struct sr_serial_dev_inst *serial, int baudrate,
  *
  * @param serial Previously initialized serial port structure.
  * @param paramstr A serial communication parameters string, in the form
- * of <speed>/<data bits><parity><stopbits>, for example "9600/8n1" or
- * "600/7o2".
+ * of <speed>/<data bits><parity><stopbits><flow>, for example "9600/8n1" or
+ * "600/7o2" or "460800/8n1/flow=2" where flow is 0 for none, 1 for rts/cts and 2 for xon/xoff.
  *
  * @return SR_OK upon success, SR_ERR upon failure.
  */
@@ -650,11 +642,12 @@ SR_PRIV int serial_set_paramstr(struct sr_serial_dev_inst *serial,
 {
        GRegex *reg;
        GMatchInfo *match;
-       int speed, databits, parity, stopbits, rts, dtr, i;
+       int speed, databits, parity, stopbits, flow, rts, dtr, i;
        char *mstr, **opts, **kv;
 
-       speed = databits = parity = stopbits = 0;
+       speed = databits = parity = stopbits = flow = 0;
        rts = dtr = -1;
+       sr_spew("Parsing parameters from \"%s\".", paramstr);
        reg = g_regex_new(SERIAL_COMM_SPEC, 0, 0, NULL);
        if (g_regex_match(reg, paramstr, 0, &match)) {
                if ((mstr = g_match_info_fetch(match, 1)))
@@ -707,6 +700,17 @@ SR_PRIV int serial_set_paramstr(struct sr_serial_dev_inst *serial,
                                                        sr_dbg("invalid value for dtr: %c", kv[1][0]);
                                                        speed = 0;
                                                }
+                                       } else if (!strncmp(kv[0], "flow", 4)) {
+                                               if (kv[1][0] == '0')
+                                                       flow = 0;
+                                               else if (kv[1][0] == '1')
+                                                       flow = 1;
+                                               else if (kv[1][0] == '2')
+                                                       flow = 2;
+                                               else {
+                                                       sr_dbg("invalid value for flow: %c", kv[1][0]);
+                                                       speed = 0;
+                                               }
                                        }
                                        g_strfreev(kv);
                                }
@@ -718,11 +722,13 @@ SR_PRIV int serial_set_paramstr(struct sr_serial_dev_inst *serial,
        g_match_info_unref(match);
        g_regex_unref(reg);
 
-       if (speed)
-               return serial_set_params(serial, speed, databits, parity, stopbits,
-                               0, rts, dtr);
-       else
+       if (speed) {
+               return serial_set_params(serial, speed, databits, parity,
+                                        stopbits, flow, rts, dtr);
+       } else {
+               sr_dbg("Could not infer speed from parameter string.");
                return SR_ERR_ARG;
+       }
 }
 
 /**
@@ -831,7 +837,7 @@ SR_PRIV int serial_stream_detect(struct sr_serial_dev_inst *serial,
                if (len > 0) {
                        ibuf += len;
                } else if (len == 0) {
-                       sr_spew("Error: Only read 0 bytes.");
+                       /* No logging, already done in serial_read(). */
                } else {
                        /* Error reading byte, but continuing anyway. */
                }