broadband-bearer: once connected, set flow control settings

During modem initialization we detected the flow control settings
supported by the modem, and selected the best one to use from them,
notifying it to the device via AT+IFC. The device was therefore
instructed to use that flow control setting for data transmission in
the TTY (i.e. not during AT control commands).

The missing thing was to also configure ourselves our end of the
serial port with the same flow control settings when getting into data
mode. By doing it ourselves, we avoid requiring any explicit setting
in pppd for flow control; pppd can assume the flow control settings
are already the expected ones.

Worth noting that all this setup is completely ignored for TTYs
exposed directly via USB.

https://bugs.freedesktop.org/show_bug.cgi?id=100394

7 files changed, 196 insertions, 16 deletions

diff --git a/.gitignore b/.gitignore
index 03c7d52e..9e79d258 100644
--- a/.gitignore
+++ b/.gitignore
@@ -48,6 +48,8 @@ Makefile.in
 /src/mm-daemon-enums-types.h
 /src/mm-port-enums-types.c
 /src/mm-port-enums-types.h
+/src/mm-helper-enums-types.c
+/src/mm-helper-enums-types.h
 /src/mm-marshal.[ch]
 /src/tests/test-modem-helpers
 /src/tests/test-modem-helpers-qmi
diff --git a/src/Makefile.am b/src/Makefile.am
index 91b4e17a..13481e96 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -67,6 +67,28 @@ EXTRA_DIST += $(udevrules_DATA)
 
 noinst_LTLIBRARIES += libhelpers.la
 
+HELPER_ENUMS_INPUTS = \
+	$(srcdir)/mm-modem-helpers.h \
+	$(NULL)
+
+HELPER_ENUMS_GENERATED = \
+	mm-helper-enums-types.h \
+	mm-helper-enums-types.c \
+	$(NULL)
+
+mm-helper-enums-types.h: Makefile.am $(HELPER_ENUMS_INPUTS) $(top_srcdir)/build-aux/mm-enums-template.h
+	$(AM_V_GEN) $(GLIB_MKENUMS) \
+		--fhead "#include \"mm-modem-helpers.h\"\n#ifndef __MM_HELPER_ENUMS_TYPES_H__\n#define __MM_HELPER_ENUMS_TYPES_H__\n" \
+		--template $(top_srcdir)/build-aux/mm-enums-template.h \
+		--ftail "#endif /* __MM_HELPER_ENUMS_TYPES_H__ */\n" \
+		$(HELPER_ENUMS_INPUTS) > $@
+
+mm-helper-enums-types.c: Makefile.am $(top_srcdir)/build-aux/mm-enums-template.c mm-helper-enums-types.h
+	$(AM_V_GEN) $(GLIB_MKENUMS) \
+		--fhead "#include \"mm-helper-enums-types.h\"" \
+		--template $(top_srcdir)/build-aux/mm-enums-template.c \
+		$(HELPER_ENUMS_INPUTS) > $@
+
 libhelpers_la_SOURCES = \
 	mm-error-helpers.c \
 	mm-error-helpers.h \
@@ -82,6 +104,8 @@ libhelpers_la_SOURCES = \
 	mm-sms-part-cdma.c \
 	$(NULL)
 
+nodist_libhelpers_la_SOURCES = $(HELPER_ENUMS_GENERATED)
+
 if WITH_QMI
 libhelpers_la_SOURCES += \
 	mm-modem-helpers-qmi.c \
@@ -96,6 +120,10 @@ libhelpers_la_SOURCES += \
 	$(NULL)
 endif
 
+# Request to build enum types before anything else
+BUILT_SOURCES += $(HELPER_ENUMS_GENERATED)
+CLEANFILES    += $(HELPER_ENUMS_GENERATED)
+
 ################################################################################
 # kerneldevice library
 ################################################################################
diff --git a/src/mm-broadband-bearer.c b/src/mm-broadband-bearer.c
index 0565eee3..ac701733 100644
--- a/src/mm-broadband-bearer.c
+++ b/src/mm-broadband-bearer.c
@@ -35,6 +35,7 @@
 #include "mm-log.h"
 #include "mm-modem-helpers.h"
 #include "mm-port-enums-types.h"
+#include "mm-helper-enums-types.h"
 
 static void async_initable_iface_init (GAsyncInitableIface *iface);
 
@@ -48,6 +49,14 @@ typedef enum {
     CONNECTION_TYPE_CDMA,
 } ConnectionType;
 
+enum {
+    PROP_0,
+    PROP_FLOW_CONTROL,
+    PROP_LAST
+};
+
+static GParamSpec *properties[PROP_LAST];
+
 struct _MMBroadbandBearerPrivate {
     /*-- Common stuff --*/
     /* Data port used when modem is connected */
@@ -55,6 +64,9 @@ struct _MMBroadbandBearerPrivate {
     /* Current connection type */
     ConnectionType connection_type;
 
+    /* PPP specific */
+    MMFlowControl flow_control;
+
     /*-- 3GPP specific --*/
     /* CID of the PDP context */
     guint cid;
@@ -254,6 +266,20 @@ dial_cdma_ready (MMBaseModem *modem,
         return;
     }
 
+    /* Configure flow control to use while connected */
+    if (ctx->self->priv->flow_control != MM_FLOW_CONTROL_NONE) {
+        gchar *flow_control_str;
+
+        flow_control_str = mm_flow_control_build_string_from_mask (ctx->self->priv->flow_control);
+        mm_dbg ("[%s] Setting flow control: %s", mm_port_get_device (ctx->data), flow_control_str);
+        g_free (flow_control_str);
+
+        if (!mm_port_serial_set_flow_control (MM_PORT_SERIAL (ctx->data), ctx->self->priv->flow_control, &error)) {
+            mm_warn ("Couldn't set flow control settings: %s", error->message);
+            g_clear_error (&error);
+        }
+    }
+
     /* The ATD command has succeeded, and therefore the TTY is in data mode now.
      * Instead of waiting for setting the port as connected later in
      * connect_succeeded(), we do it right away so that we stop our polling. */
@@ -557,6 +583,8 @@ atd_ready (MMBaseModem *modem,
            GAsyncResult *res,
            Dial3gppContext *ctx)
 {
+    GError *error = NULL;
+
     /* DO NOT check for cancellable here. If we got here without errors, the
      * bearer is really connected and therefore we need to reflect that in
      * the state machine. */
@@ -576,6 +604,20 @@ atd_ready (MMBaseModem *modem,
         return;
     }
 
+    /* Configure flow control to use while connected */
+    if (ctx->self->priv->flow_control != MM_FLOW_CONTROL_NONE) {
+        gchar *flow_control_str;
+
+        flow_control_str = mm_flow_control_build_string_from_mask (ctx->self->priv->flow_control);
+        mm_dbg ("[%s] Setting flow control: %s", mm_port_get_device (MM_PORT (ctx->dial_port)), flow_control_str);
+        g_free (flow_control_str);
+
+        if (!mm_port_serial_set_flow_control (MM_PORT_SERIAL (ctx->dial_port), ctx->self->priv->flow_control, &error)) {
+            mm_warn ("Couldn't set flow control settings: %s", error->message);
+            g_clear_error (&error);
+        }
+    }
+
     /* The ATD command has succeeded, and therefore the TTY is in data mode now.
      * Instead of waiting for setting the port as connected later in
      * connect_succeeded(), we do it right away so that we stop our polling. */
@@ -1455,6 +1497,16 @@ data_flash_cdma_ready (MMPortSerial *data,
 
     mm_port_serial_flash_finish (data, res, &error);
 
+    /* Cleanup flow control */
+    if (ctx->self->priv->flow_control != MM_FLOW_CONTROL_NONE) {
+        GError *flow_control_error = NULL;
+
+        if (!mm_port_serial_set_flow_control (MM_PORT_SERIAL (data), MM_FLOW_CONTROL_NONE, &flow_control_error)) {
+            mm_dbg ("Couldn't reset flow control settings: %s", flow_control_error->message);
+            g_clear_error (&flow_control_error);
+        }
+    }
+
     /* We kept the serial port open during connection, now we close that open
      * count */
     mm_port_serial_close (data);
@@ -1572,6 +1624,16 @@ data_flash_3gpp_ready (MMPortSerial *data,
 
     mm_port_serial_flash_finish (data, res, &error);
 
+    /* Cleanup flow control */
+    if (ctx->self->priv->flow_control != MM_FLOW_CONTROL_NONE) {
+        GError *flow_control_error = NULL;
+
+        if (!mm_port_serial_set_flow_control (MM_PORT_SERIAL (data), MM_FLOW_CONTROL_NONE, &flow_control_error)) {
+            mm_dbg ("Couldn't reset flow control settings: %s", flow_control_error->message);
+            g_clear_error (&flow_control_error);
+        }
+    }
+
     /* We kept the serial port open during connection, now we close that open
      * count */
     mm_port_serial_close (data);
@@ -2252,18 +2314,62 @@ mm_broadband_bearer_new (MMBroadbandModem *modem,
                          GAsyncReadyCallback callback,
                          gpointer user_data)
 {
+    MMFlowControl flow_control;
+
+    /* Inherit flow control from modem object directly */
+    g_object_get (modem,
+                  MM_BROADBAND_MODEM_FLOW_CONTROL, &flow_control,
+                  NULL);
+
     g_async_initable_new_async (
         MM_TYPE_BROADBAND_BEARER,
         G_PRIORITY_DEFAULT,
         cancellable,
         callback,
         user_data,
-        MM_BASE_BEARER_MODEM,  modem,
-        MM_BASE_BEARER_CONFIG, properties,
+        MM_BASE_BEARER_MODEM,             modem,
+        MM_BASE_BEARER_CONFIG,            properties,
+        MM_BROADBAND_BEARER_FLOW_CONTROL, flow_control,
         NULL);
 }
 
 static void
+set_property (GObject      *object,
+              guint         prop_id,
+              const GValue *value,
+              GParamSpec   *pspec)
+{
+    MMBroadbandBearer *self = MM_BROADBAND_BEARER (object);
+
+    switch (prop_id) {
+    case PROP_FLOW_CONTROL:
+        self->priv->flow_control = g_value_get_flags (value);
+        break;
+    default:
+        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+        break;
+    }
+}
+
+static void
+get_property (GObject    *object,
+              guint       prop_id,
+              GValue     *value,
+              GParamSpec *pspec)
+{
+    MMBroadbandBearer *self = MM_BROADBAND_BEARER (object);
+
+    switch (prop_id) {
+    case PROP_FLOW_CONTROL:
+        g_value_set_flags (value, self->priv->flow_control);
+        break;
+    default:
+        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+        break;
+    }
+}
+
+static void
 mm_broadband_bearer_init (MMBroadbandBearer *self)
 {
     /* Initialize private data */
@@ -2273,6 +2379,7 @@ mm_broadband_bearer_init (MMBroadbandBearer *self)
 
     /* Set defaults */
     self->priv->connection_type = CONNECTION_TYPE_NONE;
+    self->priv->flow_control    = MM_FLOW_CONTROL_NONE;
 }
 
 static void
@@ -2300,8 +2407,9 @@ mm_broadband_bearer_class_init (MMBroadbandBearerClass *klass)
 
     g_type_class_add_private (object_class, sizeof (MMBroadbandBearerPrivate));
 
-    /* Virtual methods */
-    object_class->dispose = dispose;
+    object_class->get_property = get_property;
+    object_class->set_property = set_property;
+    object_class->dispose      = dispose;
 
     base_bearer_class->connect = connect;
     base_bearer_class->connect_finish = connect_finish;
@@ -2325,4 +2433,13 @@ mm_broadband_bearer_class_init (MMBroadbandBearerClass *klass)
     klass->disconnect_3gpp_finish = detailed_disconnect_finish;
     klass->disconnect_cdma = disconnect_cdma;
     klass->disconnect_cdma_finish = detailed_disconnect_finish;
+
+    properties[PROP_FLOW_CONTROL] =
+        g_param_spec_flags (MM_BROADBAND_BEARER_FLOW_CONTROL,
+                            "Flow control",
+                            "Flow control settings to use during connection",
+                            MM_TYPE_FLOW_CONTROL,
+                            MM_FLOW_CONTROL_NONE,
+                            G_PARAM_READWRITE);
+    g_object_class_install_property (object_class, PROP_FLOW_CONTROL, properties[PROP_FLOW_CONTROL]);
 }
diff --git a/src/mm-broadband-bearer.h b/src/mm-broadband-bearer.h
index bee2c521..c317bb5f 100644
--- a/src/mm-broadband-bearer.h
+++ b/src/mm-broadband-bearer.h
@@ -25,6 +25,7 @@
 #define _LIBMM_INSIDE_MM
 #include <libmm-glib.h>
 
+#include "mm-modem-helpers.h"
 #include "mm-base-bearer.h"
 #include "mm-broadband-modem.h"
 
@@ -39,6 +40,8 @@ typedef struct _MMBroadbandBearer MMBroadbandBearer;
 typedef struct _MMBroadbandBearerClass MMBroadbandBearerClass;
 typedef struct _MMBroadbandBearerPrivate MMBroadbandBearerPrivate;
 
+#define MM_BROADBAND_BEARER_FLOW_CONTROL "broadband-bearer-flow-control"
+
 struct _MMBroadbandBearer {
     MMBaseBearer parent;
     MMBroadbandBearerPrivate *priv;
diff --git a/src/mm-broadband-modem.c b/src/mm-broadband-modem.c
index bb5c6d1a..4a14d33d 100644
--- a/src/mm-broadband-modem.c
+++ b/src/mm-broadband-modem.c
@@ -55,6 +55,7 @@
 #include "libqcdm/src/commands.h"
 #include "libqcdm/src/logs.h"
 #include "libqcdm/src/log-items.h"
+#include "mm-helper-enums-types.h"
 
 static void iface_modem_init (MMIfaceModem *iface);
 static void iface_modem_3gpp_init (MMIfaceModem3gpp *iface);
@@ -115,9 +116,12 @@ enum {
     PROP_MODEM_VOICE_CALL_LIST,
     PROP_MODEM_SIMPLE_STATUS,
     PROP_MODEM_SIM_HOT_SWAP_SUPPORTED,
+    PROP_FLOW_CONTROL,
     PROP_LAST
 };
 
+static GParamSpec *properties[PROP_LAST];
+
 /* When CIND is supported, invalid indicators are marked with this value */
 #define CIND_INDICATOR_INVALID 255
 #define CIND_INDICATOR_IS_VALID(u) (u != CIND_INDICATOR_INVALID)
@@ -146,6 +150,7 @@ struct _MMBroadbandModemPrivate {
     guint modem_cind_max_signal_quality;
     guint modem_cind_indicator_roaming;
     guint modem_cind_indicator_service;
+    MMFlowControl flow_control;
 
     /*<--- Modem 3GPP interface --->*/
     /* Properties */
@@ -3124,17 +3129,20 @@ modem_setup_flow_control_finish (MMIfaceModem  *self,
 }
 
 static void
-ifc_test_ready (MMBaseModem  *self,
+ifc_test_ready (MMBaseModem  *_self,
                 GAsyncResult *res,
                 GTask        *task)
 {
-    GError        *error = NULL;
-    const gchar   *response;
-    MMFlowControl  mask;
-    const gchar   *cmd;
+    MMBroadbandModem *self;
+    GError           *error = NULL;
+    const gchar      *response;
+    MMFlowControl     mask;
+    const gchar      *cmd;
+
+    self = MM_BROADBAND_MODEM (_self);
 
     /* Completely ignore errors in AT+IFC=? */
-    response = mm_base_modem_at_command_finish (self, res, &error);
+    response = mm_base_modem_at_command_finish (_self, res, &error);
     if (!response)
         goto out;
 
@@ -3148,17 +3156,23 @@ ifc_test_ready (MMBaseModem  *self,
      *  XON/XOFF
      *  None.
      */
-    if (mask & MM_FLOW_CONTROL_RTS_CTS)
+    if (mask & MM_FLOW_CONTROL_RTS_CTS) {
+        self->priv->flow_control = MM_FLOW_CONTROL_RTS_CTS;
         cmd = "+IFC=2,2";
-    else if (mask & MM_FLOW_CONTROL_XON_XOFF)
+    } else if (mask & MM_FLOW_CONTROL_XON_XOFF) {
+        self->priv->flow_control = MM_FLOW_CONTROL_XON_XOFF;
         cmd = "+IFC=1,1";
-    else if (mask & MM_FLOW_CONTROL_NONE)
+    } else if (mask & MM_FLOW_CONTROL_NONE) {
+        self->priv->flow_control = MM_FLOW_CONTROL_NONE;
         cmd = "+IFC=0,0";
-    else
+    } else
         g_assert_not_reached ();
 
+    /* Notify the flow control property update */
+    g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_FLOW_CONTROL]);
+
     /* Set flow control settings and ignore result */
-    mm_base_modem_at_command (self, cmd, 3, FALSE, NULL, NULL);
+    mm_base_modem_at_command (_self, cmd, 3, FALSE, NULL, NULL);
 
 out:
     /* Ignore errors */
@@ -10647,6 +10661,9 @@ get_property (GObject *object,
     case PROP_MODEM_SIM_HOT_SWAP_SUPPORTED:
         g_value_set_boolean (value, self->priv->sim_hot_swap_supported);
         break;
+    case PROP_FLOW_CONTROL:
+        g_value_set_flags (value, self->priv->flow_control);
+        break;
     default:
         G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
         break;
@@ -10676,6 +10693,7 @@ mm_broadband_modem_init (MMBroadbandModem *self)
     self->priv->current_sms_mem1_storage = MM_SMS_STORAGE_UNKNOWN;
     self->priv->current_sms_mem2_storage = MM_SMS_STORAGE_UNKNOWN;
     self->priv->sim_hot_swap_supported = FALSE;
+    self->priv->flow_control = MM_FLOW_CONTROL_NONE;
 }
 
 static void
@@ -11138,4 +11156,13 @@ mm_broadband_modem_class_init (MMBroadbandModemClass *klass)
     g_object_class_override_property (object_class,
                                       PROP_MODEM_SIM_HOT_SWAP_SUPPORTED,
                                       MM_IFACE_MODEM_SIM_HOT_SWAP_SUPPORTED);
+
+    properties[PROP_FLOW_CONTROL] =
+        g_param_spec_flags (MM_BROADBAND_MODEM_FLOW_CONTROL,
+                            "Flow control",
+                            "Flow control settings to use in the connected TTY",
+                            MM_TYPE_FLOW_CONTROL,
+                            MM_FLOW_CONTROL_NONE,
+                            G_PARAM_READABLE);
+    g_object_class_install_property (object_class, PROP_FLOW_CONTROL, properties[PROP_FLOW_CONTROL]);
 }
diff --git a/src/mm-broadband-modem.h b/src/mm-broadband-modem.h
index d6b55d9d..4625b22a 100644
--- a/src/mm-broadband-modem.h
+++ b/src/mm-broadband-modem.h
@@ -24,6 +24,7 @@
 
 #include <ModemManager.h>
 
+#include "mm-modem-helpers.h"
 #include "mm-charsets.h"
 #include "mm-base-modem.h"
 
@@ -38,6 +39,8 @@ typedef struct _MMBroadbandModem MMBroadbandModem;
 typedef struct _MMBroadbandModemClass MMBroadbandModemClass;
 typedef struct _MMBroadbandModemPrivate MMBroadbandModemPrivate;
 
+#define MM_BROADBAND_MODEM_FLOW_CONTROL "broadband-modem-flow-control"
+
 struct _MMBroadbandModem {
     MMBaseModem parent;
     MMBroadbandModemPrivate *priv;
diff --git a/src/mm-modem-helpers.h b/src/mm-modem-helpers.h
index bd10b940..297e15df 100644
--- a/src/mm-modem-helpers.h
+++ b/src/mm-modem-helpers.h
@@ -101,7 +101,7 @@ GRegex *mm_voice_clip_regex_get (void);
  * For simplicity, we'll only consider flow control methods available in both
  * TE and TA. */
 
-typedef enum {
+typedef enum { /*< underscore_name=mm_flow_control >*/
     MM_FLOW_CONTROL_UNKNOWN   = 0,
     MM_FLOW_CONTROL_NONE      = 1 << 0,  /* IFC=0,0 */
     MM_FLOW_CONTROL_XON_XOFF  = 1 << 1,  /* IFC=1,1 */