broadband-modem/libqcdm: add signal strength from QCDM EVDO Pilot Sets log messages

When a CDMA-only modem is registered with the EVDO network, its not possible to
read signal strength in the following cases:

1) while a data connection is active on single-AT-port modems, because the AT
port is used for PPP and not available for AT+CSQ, AT+CIND or vendor-specific
signal strength commands

2) when the modem reports only CDMA 1x signal strength with AT+CSQ

Now that we have a reasonable interpretation of RSSI from the QCDM
EVDO Pilot Sets V2 log messgae, use that when other means of getting
signal strength aren't available.

1 files changed, 156 insertions, 4 deletions

diff --git a/src/mm-port-serial-qcdm.c b/src/mm-port-serial-qcdm.c
index 7732851f..e997bb06 100644
--- a/src/mm-port-serial-qcdm.c
+++ b/src/mm-port-serial-qcdm.c
@@ -26,10 +26,15 @@
 #include "libqcdm/src/com.h"
 #include "libqcdm/src/utils.h"
 #include "libqcdm/src/errors.h"
+#include "libqcdm/src/dm-commands.h"
 #include "mm-log.h"
 
 G_DEFINE_TYPE (MMPortSerialQcdm, mm_port_serial_qcdm, MM_TYPE_PORT_SERIAL)
 
+struct _MMPortSerialQcdmPrivate {
+    GSList *unsolicited_msg_handlers;
+};
+
 /*****************************************************************************/
 
 static gboolean
@@ -60,10 +65,10 @@ find_qcdm_start (GByteArray *response, gsize *start)
 }
 
 static MMPortSerialResponseType
-parse_response (MMPortSerial *port,
-                GByteArray *response,
-                GByteArray **parsed_response,
-                GError **error)
+parse_qcdm (GByteArray *response,
+            gboolean want_log,
+            GByteArray **parsed_response,
+            GError **error)
 {
     gsize start = 0;
     gsize used = 0;
@@ -111,6 +116,14 @@ parse_response (MMPortSerial *port,
         return MM_PORT_SERIAL_RESPONSE_NONE;
     }
 
+    if (want_log && unescaped_buffer[0] != DIAG_CMD_LOG) {
+        /* If we only want log items and this isn't one, don't remove this
+         * DM packet from the buffer.
+         */
+        g_free (unescaped_buffer);
+        return MM_PORT_SERIAL_RESPONSE_NONE;
+    }
+
     /* Successfully decapsulated the DM command. We'll build a new byte array
      * with the response, and leave the input buffer cleaned up. */
     g_assert (unescaped_len <= 1024);
@@ -124,6 +137,15 @@ parse_response (MMPortSerial *port,
     return MM_PORT_SERIAL_RESPONSE_BUFFER;
 }
 
+static MMPortSerialResponseType
+parse_response (MMPortSerial *port,
+                GByteArray *response,
+                GByteArray **parsed_response,
+                GError **error)
+{
+    return parse_qcdm (response, FALSE, parsed_response, error);
+}
+
 /*****************************************************************************/
 
 GByteArray *
@@ -202,6 +224,111 @@ debug_log (MMPortSerial *port, const char *prefix, const char *buf, gsize len)
 
 /*****************************************************************************/
 
+typedef struct {
+    guint log_code;
+    MMPortSerialQcdmUnsolicitedMsgFn callback;
+    gboolean enable;
+    gpointer user_data;
+    GDestroyNotify notify;
+} MMQcdmUnsolicitedMsgHandler;
+
+static gint
+unsolicited_msg_handler_cmp (MMQcdmUnsolicitedMsgHandler *handler,
+                             gpointer log_code)
+{
+    return handler->log_code - GPOINTER_TO_UINT (log_code);
+}
+
+void
+mm_port_serial_qcdm_add_unsolicited_msg_handler (MMPortSerialQcdm *self,
+                                                 guint log_code,
+                                                 MMPortSerialQcdmUnsolicitedMsgFn callback,
+                                                 gpointer user_data,
+                                                 GDestroyNotify notify)
+{
+    GSList *existing;
+    MMQcdmUnsolicitedMsgHandler *handler;
+
+    g_return_if_fail (MM_IS_PORT_SERIAL_QCDM (self));
+    g_return_if_fail (log_code > 0 && log_code <= G_MAXUINT16);
+
+    existing = g_slist_find_custom (self->priv->unsolicited_msg_handlers,
+                                    GUINT_TO_POINTER (log_code),
+                                    (GCompareFunc)unsolicited_msg_handler_cmp);
+    if (existing) {
+        handler = existing->data;
+        /* We OVERWRITE any existing one, so if any context data existing, free it */
+        if (handler->notify)
+            handler->notify (handler->user_data);
+    } else {
+        handler = g_slice_new (MMQcdmUnsolicitedMsgHandler);
+        self->priv->unsolicited_msg_handlers = g_slist_append (self->priv->unsolicited_msg_handlers, handler);
+        handler->log_code = log_code;
+    }
+
+    handler->callback = callback;
+    handler->enable = TRUE;
+    handler->user_data = user_data;
+    handler->notify = notify;
+}
+
+void
+mm_port_serial_qcdm_enable_unsolicited_msg_handler (MMPortSerialQcdm *self,
+                                                    guint log_code,
+                                                    gboolean enable)
+{
+    GSList *existing;
+    MMQcdmUnsolicitedMsgHandler *handler;
+
+    g_return_if_fail (MM_IS_PORT_SERIAL_QCDM (self));
+    g_return_if_fail (log_code > 0 && log_code <= G_MAXUINT16);
+
+    existing = g_slist_find_custom (self->priv->unsolicited_msg_handlers,
+                                    GUINT_TO_POINTER (log_code),
+                                    (GCompareFunc)unsolicited_msg_handler_cmp);
+    if (existing) {
+        handler = existing->data;
+        handler->enable = enable;
+    }
+}
+
+static void
+parse_unsolicited (MMPortSerial *port, GByteArray *response)
+{
+    MMPortSerialQcdm *self = MM_PORT_SERIAL_QCDM (port);
+    GByteArray *log_buffer = NULL;
+    GSList *iter;
+
+    if (parse_qcdm (response,
+                    TRUE,
+                    &log_buffer,
+                    NULL) != MM_PORT_SERIAL_RESPONSE_BUFFER) {
+        return;
+    }
+
+    /* These should be guaranteed by parse_qcdm() */
+    g_return_if_fail (log_buffer);
+    g_return_if_fail (log_buffer->len > 0);
+    g_return_if_fail (log_buffer->data[0] == DIAG_CMD_LOG);
+
+    if (log_buffer->len < sizeof (DMCmdLog))
+        return;
+
+    for (iter = self->priv->unsolicited_msg_handlers; iter; iter = iter->next) {
+        MMQcdmUnsolicitedMsgHandler *handler = (MMQcdmUnsolicitedMsgHandler *) iter->data;
+        DMCmdLog *log_cmd = (DMCmdLog *) log_buffer->data;
+
+        if (!handler->enable)
+            continue;
+        if (handler->log_code != le16toh (log_cmd->log_code))
+            continue;
+        if (handler->callback)
+            handler->callback (self, log_buffer, handler->user_data);
+    }
+}
+
+/*****************************************************************************/
+
 static gboolean
 config_fd (MMPortSerial *port, int fd, GError **error)
 {
@@ -250,14 +377,39 @@ mm_port_serial_qcdm_new_fd (int fd)
 static void
 mm_port_serial_qcdm_init (MMPortSerialQcdm *self)
 {
+    self->priv = G_TYPE_INSTANCE_GET_PRIVATE (self, MM_TYPE_PORT_SERIAL_QCDM, MMPortSerialQcdmPrivate);
+}
+
+static void
+finalize (GObject *object)
+{
+    MMPortSerialQcdm *self = MM_PORT_SERIAL_QCDM (object);
+
+    while (self->priv->unsolicited_msg_handlers) {
+        MMQcdmUnsolicitedMsgHandler *handler = (MMQcdmUnsolicitedMsgHandler *) self->priv->unsolicited_msg_handlers->data;
+
+        if (handler->notify)
+            handler->notify (handler->user_data);
+
+        g_slice_free (MMQcdmUnsolicitedMsgHandler, handler);
+        self->priv->unsolicited_msg_handlers = g_slist_delete_link (self->priv->unsolicited_msg_handlers,
+                                                                    self->priv->unsolicited_msg_handlers);
+    }
+
+    G_OBJECT_CLASS (mm_port_serial_qcdm_parent_class)->finalize (object);
 }
 
 static void
 mm_port_serial_qcdm_class_init (MMPortSerialQcdmClass *klass)
 {
+    GObjectClass *object_class = G_OBJECT_CLASS (klass);
     MMPortSerialClass *port_class = MM_PORT_SERIAL_CLASS (klass);
 
+    g_type_class_add_private (object_class, sizeof (MMPortSerialQcdmPrivate));
+
     /* Virtual methods */
+    object_class->finalize = finalize;
+    port_class->parse_unsolicited = parse_unsolicited;
     port_class->parse_response = parse_response;
     port_class->config_fd = config_fd;
     port_class->debug_log = debug_log;