wavecom/sysmocom: use AT@COPS if available, instead of AT+COPS

In certain sysmocom proprietary versions of the wavecom modem,
we have a non-blocking operator scan command called AT@COPS=?,
which we can use instead of AT+COPS=?.

The wavecom vendor plugin checks at start time if the command is
available.  If yes, iti s used in case a libgsm client is asking for an
operator scan, instead of the standard AT+COPS=? variant.

2 files changed, 50 insertions, 2 deletions

diff --git a/src/gsmd/usock.c b/src/gsmd/usock.c
index 41814c8..157a874 100644
--- a/src/gsmd/usock.c
+++ b/src/gsmd/usock.c
@@ -1062,7 +1062,14 @@ static int network_opers_parse(const char *str, struct gsmd_msg_oper **out)
 	return len;
 }
 
-static int network_opers_cb(struct gsmd_atcmd *cmd, void *ctx, char *resp)
+/* should we use AT@COPS=? instead of AT+COPS=? */
+int g_use_ATatCOPS;
+
+/* the last user that requested an AT@COPS=? scan */
+struct gsmd_user *g_last_cops_user;
+int g_last_cops_id;
+
+int network_opers_cb(struct gsmd_atcmd *cmd, void *ctx, char *resp)
 {
 	struct gsmd_user *gu = ctx;
 	struct gsmd_msg_oper *buf = NULL;
@@ -1206,7 +1213,12 @@ static int usock_rcv_network(struct gsmd_user *gu, struct gsmd_msg_hdr *gph,
 		cmd = atcmd_fill("AT+COPS?", 8+1, &network_oper_n_cb, gu, 0, NULL);
 		break;
 	case GSMD_NETWORK_OPER_LIST:
-		cmd = atcmd_fill("AT+COPS=?", 9+1, &network_opers_cb, gu, 0, NULL);
+		if (g_use_ATatCOPS) {
+			g_last_cops_user = gu;
+			g_last_cops_id = cmd->id;
+			cmd = atcmd_fill("AT@COPS=?", 9+1, &network_opers_cb, gu, 0, NULL);
+		} else
+			cmd = atcmd_fill("AT+COPS=?", 9+1, &network_opers_cb, gu, 0, NULL);
 		break;
 	case GSMD_NETWORK_PREF_LIST:
 		/* Set long alphanumeric format */
diff --git a/src/gsmd/vendor_wavecom.c b/src/gsmd/vendor_wavecom.c
index b1b6929..dc309ab 100644
--- a/src/gsmd/vendor_wavecom.c
+++ b/src/gsmd/vendor_wavecom.c
@@ -213,10 +213,34 @@ static int sais_parse(const char *buf, int len, const char *param,
 	return 0;
 };
 
+static int cops_parse(const char *buf, int len, const char *param,
+		     struct gsmd *gsmd)
+{
+	struct gsmd_atcmd fake_atcmd;
+
+	if (!g_use_ATatCOPS)
+		return 0;
+
+	if (!strcmp(buf, "+COPS: ERROR\r\n"))
+		return 0;
+
+	if (!g_use_ATatCOPS || !g_last_cops_user)
+		return 0;
+
+	fake_atcmd.id = g_last_cops_id;
+
+	network_opers_cb(&fake_atcmd, g_last_cops_user, buf);
+
+	return 0;
+};
+
+
 static const struct gsmd_unsolicit wavecom_unsolicit[] = {
 	{ "+CCED",		&cced_parse },	/* Cell Environment Report */
 	{ "+SYSMOCOM_GPS",	&sgps_parse },
 	{ "+SYSMOCOM_AIS",	&sais_parse },
+	/* proprietary non-blocking response to AT@COPS=? */
+	{ "+COPS",		&cops_parse },
 };
 
 static int wavecom_detect(struct gsmd *g)
@@ -225,6 +249,15 @@ static int wavecom_detect(struct gsmd *g)
 	return 1;
 }
 
+static int at_atcops_cb(struct gsmd_atcmd *cmd, void *ctx, char *resp)
+{
+	/* if the result is successful, at@cops is supported */
+	if (cmd->ret == 0)
+		g_use_ATatCOPS = 1;
+
+	return 0;
+}
+
 static int wavecom_initsettings(struct gsmd *g)
 {
 	int rc = 0;
@@ -255,6 +288,9 @@ static int wavecom_initsettings(struct gsmd *g)
 	rc |= gsmd_simplecmd(g, "AT+WREGC=0");
 	rc |= gsmd_simplecmd(g, "AT+CCED=1,3");
 
+	cmd = atcmd_fill("AT@COPS=?", 9+1, &at_atcops_cb, NULL, 0, NULL);
+	rc |= atcmd_submit(g, cmd);
+
 	return rc;
 }