diff --git a/introspection/org.freedesktop.ModemManager1.Call.xml b/introspection/org.freedesktop.ModemManager1.Call.xml
index 739d8385..659601b4 100644
--- a/introspection/org.freedesktop.ModemManager1.Call.xml
+++ b/introspection/org.freedesktop.ModemManager1.Call.xml
@@ -40,13 +40,13 @@
 
     <!--
         Deflect:
-	@number: new number where the call will be deflected.
+        @number: new number where the call will be deflected.
 
         Deflect an incoming or waiting call to a new number. This call will be
-	considered terminated once the deflection is performed.
+        considered terminated once the deflection is performed.
 
         Applicable only if state is <link linkend="MM-CALL-STATE-RINGING-IN:CAPS"><constant>MM_CALL_STATE_RINGING_IN</constant></link> or
-	<link linkend="MM-CALL-STATE-WAITING:CAPS"><constant>MM_CALL_STATE_WAITING</constant></link> and direction is
+        <link linkend="MM-CALL-STATE-WAITING:CAPS"><constant>MM_CALL_STATE_WAITING</constant></link> and direction is
         <link linkend="MM-CALL-DIRECTION-INCOMING:CAPS"><constant>MM_CALL_DIRECTION_INCOMING</constant></link>.
     -->
     <method name="Deflect">
@@ -57,7 +57,7 @@
         JoinMultiparty:
 
         Join the currently held call into a single multiparty call with another
-	already active call.
+        already active call.
 
         The calls will be flagged with the
         '<link linkend="gdbus-property-org-freedesktop-ModemManager1-Call.Multiparty">Multiparty</link>'
diff --git a/introspection/org.freedesktop.ModemManager1.Modem.Voice.xml b/introspection/org.freedesktop.ModemManager1.Modem.Voice.xml
index d39081c0..59f11e9d 100644
--- a/introspection/org.freedesktop.ModemManager1.Modem.Voice.xml
+++ b/introspection/org.freedesktop.ModemManager1.Modem.Voice.xml
@@ -127,10 +127,10 @@
         CallWaitingSetup:
 
         Activates or deactivates the call waiting network service, as per
-	3GPP TS 22.083.
+        3GPP TS 22.083.
 
-	This operation requires communication with the network in order to
-	complete, so the modem must be successfully registered.
+        This operation requires communication with the network in order to
+        complete, so the modem must be successfully registered.
     -->
     <method name="CallWaitingSetup">
       <arg name="enable" type="b" direction="in" />
@@ -140,10 +140,10 @@
         CallWaitingQuery:
 
         Queries the status of the call waiting network service, as per
-	3GPP TS 22.083.
+        3GPP TS 22.083.
 
-	This operation requires communication with the network in order to
-	complete, so the modem must be successfully registered.
+        This operation requires communication with the network in order to
+        complete, so the modem must be successfully registered.
     -->
     <method name="CallWaitingQuery">
       <arg name="status" type="b" direction="out" />
diff --git a/introspection/org.freedesktop.ModemManager1.Modem.xml b/introspection/org.freedesktop.ModemManager1.Modem.xml
index 0fc5741d..eb4debd8 100644
--- a/introspection/org.freedesktop.ModemManager1.Modem.xml
+++ b/introspection/org.freedesktop.ModemManager1.Modem.xml
@@ -132,11 +132,11 @@
 
     <!--
         SetPowerState:
-	@state: A <link linkend="MMModemPowerState">MMModemPowerState</link> value, to specify the desired power state.
+        @state: A <link linkend="MMModemPowerState">MMModemPowerState</link> value, to specify the desired power state.
 
         Set the power state of the modem. This action can only be run when the
-	modem is in <link linkend="MM-MODEM-STATE-DISABLED:CAPS"><constant>MM_MODEM_STATE_DISABLED</constant></link>
-	state.
+        modem is in <link linkend="MM-MODEM-STATE-DISABLED:CAPS"><constant>MM_MODEM_STATE_DISABLED</constant></link>
+        state.
     -->
     <method name="SetPowerState">
       <arg name="state" type="u" direction="in" />
@@ -424,9 +424,9 @@
         StateFailedReason:
 
         Error specifying why the modem is in
-	<link linkend="MM-MODEM-STATE-FAILED:CAPS"><constant>MM_MODEM_STATE_FAILED</constant></link>
-	state, given as a
-	<link linkend="MMModemStateFailedReason">MMModemStateFailedReason</link> value.
+        <link linkend="MM-MODEM-STATE-FAILED:CAPS"><constant>MM_MODEM_STATE_FAILED</constant></link>
+        state, given as a
+        <link linkend="MMModemStateFailedReason">MMModemStateFailedReason</link> value.
     -->
     <property name="StateFailedReason" type="u" access="read" />
 
@@ -466,8 +466,8 @@
     <!--
         PowerState:
 
-	A <link linkend="MMModemPowerState">MMModemPowerState</link> value
-	specifying the current power state of the modem.
+        A <link linkend="MMModemPowerState">MMModemPowerState</link> value
+        specifying the current power state of the modem.
     -->
     <property name="PowerState" type="u" access="read" />
 
diff --git a/introspection/org.freedesktop.ModemManager1.Sms.xml b/introspection/org.freedesktop.ModemManager1.Sms.xml
index 1bd2150e..91df019d 100644
--- a/introspection/org.freedesktop.ModemManager1.Sms.xml
+++ b/introspection/org.freedesktop.ModemManager1.Sms.xml
@@ -109,8 +109,8 @@
          <varlistentry><term><link linkend="MM-SMS-VALIDITY-TYPE-RELATIVE:CAPS">MM_SMS_VALIDITY_TYPE_RELATIVE</link></term>
           <listitem>
            <para>
-	        The value is the length of the validity period in minutes, given
-	        as an unsigned integer (D-Bus signature <literal>'u'</literal>).
+             The value is the length of the validity period in minutes, given
+             as an unsigned integer (D-Bus signature <literal>'u'</literal>).
             </para>
           </listitem>
          </varlistentry>