]> sigrok.org Git - libsigrok.git/blobdiff - hardware/tekpower-dmm/api.c
serial: Use OS-independent flags for serial port opening.
[libsigrok.git] / hardware / tekpower-dmm / api.c
index f6a649c1032341fcc6e8103f4a2945b2c1331703..dd53f4dd3d64b017fc4ac823f66c1799521ea0eb 100644 (file)
@@ -28,6 +28,8 @@
 #include "libsigrok-internal.h"
 #include "protocol.h"
 
+#define SERIALCOMM "2400/8n1"
+
 static const int hwopts[] = {
        SR_HWOPT_CONN,
        SR_HWOPT_SERIALCOMM,
@@ -95,90 +97,73 @@ static GSList *lcd14_scan(const char *conn, const char *serialcomm)
        struct drv_context *drvc;
        struct dev_context *devc;
        struct sr_probe *probe;
+       struct sr_serial_dev_inst *serial;
        GSList *devices;
-       int i, len, fd, retry, good_packets = 0, dropped, ret;
-       uint8_t buf[128], *b;
+       int dropped, ret;
+       size_t len;
+       uint8_t buf[128];
 
-       if ((fd = serial_open(conn, O_RDONLY | O_NONBLOCK)) == -1) {
-               sr_err("Unable to open %s: %s.", conn, strerror(errno));
+       if (!(serial = sr_serial_dev_inst_new(conn, serialcomm)))
                return NULL;
-       }
-       if ((ret = serial_set_paramstr(fd, serialcomm)) != SR_OK) {
-               sr_err("Unable to set serial parameters: %d", ret);
+
+       if (serial_open(serial, SERIAL_RDONLY | SERIAL_NONBLOCK) != SR_OK)
                return NULL;
-       }
 
        sr_info("Probing port %s readonly.", conn);
 
        drvc = di->priv;
-       b = buf;
-       retry = 0;
        devices = NULL;
-       serial_flush(fd);
+       serial_flush(serial);
 
        /*
         * There's no way to get an ID from the multimeter. It just sends data
         * periodically, so the best we can do is check if the packets match
         * the expected format.
         */
-       while (!devices && retry < 3) {
-               retry++;
-
-               /* Let's get a bit of data and see if we can find a packet. */
-               len = sizeof(buf);
-               serial_readline(fd, (char **)&b, &len, 500);
-               if ((len == 0) || (len < FS9721_PACKET_SIZE)) {
-                       /* Not enough data received, is the DMM connected? */
-                       continue;
-               }
 
-               /* Let's treat our buffer like a stream, and find any
-                * valid packets */
-               for (i = 0; i < len - FS9721_PACKET_SIZE + 1;) {
-                       if (!sr_fs9721_packet_valid(&buf[i])) {
-                               i++;
-                               continue;
-                       }
-                       good_packets++;
-                       i += FS9721_PACKET_SIZE;
-               }
+       /* Let's get a bit of data and see if we can find a packet. */
+       len = sizeof(buf);
 
-               /*
-                * If we dropped more than two packets worth of data,
-                * something is wrong.
-                */
-               dropped = len - (good_packets * FS9721_PACKET_SIZE);
-               if (dropped > 2 * FS9721_PACKET_SIZE)
-                       continue;
-
-               /* Let's see if we have anything good. */
-               if (good_packets == 0)
-                       continue;
+       ret = serial_stream_detect(serial, buf, &len, FS9721_PACKET_SIZE,
+                                  sr_fs9721_packet_valid, 1000, 2400);
+       if (ret != SR_OK)
+               goto scan_cleanup;
 
-               sr_info("Found device on port %s.", conn);
+       /*
+        * If we dropped more than two packets worth of data, something is
+        * wrong. We shouldn't quit however, since the dropped bytes might be
+        * just zeroes at the beginning of the stream. Those can occur as a
+        * combination of the nonstandard cable that ships with this device and
+        * the serial port or USB to serial adapter.
+        */
+       dropped = len - FS9721_PACKET_SIZE;
+       if (dropped > 2 * FS9721_PACKET_SIZE)
+               sr_warn("Had to drop too much data.");
 
-               if (!(sdi = sr_dev_inst_new(0, SR_ST_INACTIVE, "TekPower",
-                                           "TP4000ZC", "")))
-                       return NULL;
-               if (!(devc = g_try_malloc0(sizeof(struct dev_context)))) {
-                       sr_err("Device context malloc failed.");
-                       return NULL;
-               }
+       sr_info("Found device on port %s.", conn);
 
-               devc->serial = sr_serial_dev_inst_new(conn, -1);
-               devc->serialcomm = g_strdup(serialcomm);
+       if (!(sdi = sr_dev_inst_new(0, SR_ST_INACTIVE, "TekPower",
+                                   "TP4000ZC", "")))
+               goto scan_cleanup;
 
-               sdi->priv = devc;
-               sdi->driver = di;
-               if (!(probe = sr_probe_new(0, SR_PROBE_ANALOG, TRUE, "P1")))
-                       return NULL;
-               sdi->probes = g_slist_append(sdi->probes, probe);
-               drvc->instances = g_slist_append(drvc->instances, sdi);
-               devices = g_slist_append(devices, sdi);
-               break;
+       if (!(devc = g_try_malloc0(sizeof(struct dev_context)))) {
+               sr_err("Device context malloc failed.");
+               goto scan_cleanup;
        }
 
-       serial_close(fd);
+       devc->serial = serial;
+
+       sdi->priv = devc;
+       sdi->driver = di;
+       if (!(probe = sr_probe_new(0, SR_PROBE_ANALOG, TRUE, "P1")))
+               goto scan_cleanup;
+       sdi->probes = g_slist_append(sdi->probes, probe);
+       drvc->instances = g_slist_append(drvc->instances, sdi);
+       devices = g_slist_append(devices, sdi);
+
+scan_cleanup:
+       serial_close(serial);
+
        return devices;
 }
 
@@ -207,8 +192,8 @@ static GSList *hw_scan(GSList *options)
                /* Use the provided comm specs. */
                devices = lcd14_scan(conn, serialcomm);
        } else {
-               /* Try the default 2400/8n1. */
-               devices = lcd14_scan(conn, "2400/8n1");
+               /* Try the default. */
+               devices = lcd14_scan(conn, SERIALCOMM);
        }
 
        return devices;
@@ -225,7 +210,6 @@ static GSList *hw_dev_list(void)
 
 static int hw_dev_open(struct sr_dev_inst *sdi)
 {
-       int ret;
        struct dev_context *devc;
 
        if (!(devc = sdi->priv)) {
@@ -233,17 +217,9 @@ static int hw_dev_open(struct sr_dev_inst *sdi)
                return SR_ERR_BUG;
        }
 
-       devc->serial->fd = serial_open(devc->serial->port, O_RDONLY);
-       if (devc->serial->fd == -1) {
-               sr_err("Couldn't open serial port '%s'.", devc->serial->port);
+       if (serial_open(devc->serial, SERIAL_RDONLY) != SR_OK)
                return SR_ERR;
-       }
 
-       ret = serial_set_paramstr(devc->serial->fd, devc->serialcomm);
-       if (ret != SR_OK) {
-               sr_err("Unable to set serial parameters: %d.", ret);
-               return SR_ERR;
-       }
        sdi->status = SR_ST_ACTIVE;
 
        return SR_OK;
@@ -259,8 +235,7 @@ static int hw_dev_close(struct sr_dev_inst *sdi)
        }
 
        if (devc->serial && devc->serial->fd != -1) {
-               serial_close(devc->serial->fd);
-               devc->serial->fd = -1;
+               serial_close(devc->serial);
                sdi->status = SR_ST_INACTIVE;
        }