diff --git a/plugins/modem-manager/fu-mm-device.c b/plugins/modem-manager/fu-mm-device.c
index 1d42c17da..f5865c1ba 100644
--- a/plugins/modem-manager/fu-mm-device.c
+++ b/plugins/modem-manager/fu-mm-device.c
@@ -144,6 +144,7 @@ fu_mm_device_probe_default (FuDevice *device, GError **error)
 	guint n_ports = 0;
 	g_autoptr(MMFirmwareUpdateSettings) update_settings = NULL;
 	g_autofree gchar *device_sysfs_path = NULL;
+	g_autofree gchar *device_bus = NULL;
 
 	/* inhibition uid is the modem interface 'Device' property, which may
 	 * be the device sysfs path or a different user-provided id */
@@ -251,11 +252,12 @@ fu_mm_device_probe_default (FuDevice *device, GError **error)
 	}
 
 	if (self->port_at != NULL) {
-		fu_mm_utils_get_port_info (self->port_at, &device_sysfs_path, &self->port_at_ifnum, NULL);
+		fu_mm_utils_get_port_info (self->port_at, &device_bus, &device_sysfs_path, &self->port_at_ifnum, NULL);
 	}
 	if (self->port_qmi != NULL) {
 		g_autofree gchar *qmi_device_sysfs_path = NULL;
-		fu_mm_utils_get_port_info (self->port_qmi, &qmi_device_sysfs_path, &self->port_qmi_ifnum, NULL);
+		g_autofree gchar *qmi_device_bus = NULL;
+		fu_mm_utils_get_port_info (self->port_qmi, &qmi_device_bus, &qmi_device_sysfs_path, &self->port_qmi_ifnum, NULL);
 		if (device_sysfs_path == NULL && qmi_device_sysfs_path != NULL) {
 			device_sysfs_path = g_steal_pointer (&qmi_device_sysfs_path);
 		} else if (g_strcmp0 (device_sysfs_path, qmi_device_sysfs_path) != 0) {
@@ -264,14 +266,24 @@ fu_mm_device_probe_default (FuDevice *device, GError **error)
 				     device_sysfs_path, qmi_device_sysfs_path);
 			return FALSE;
 		}
+		if (device_bus == NULL && qmi_device_bus != NULL) {
+			device_bus = g_steal_pointer (&qmi_device_bus);
+		} else if (g_strcmp0 (device_bus, qmi_device_bus) != 0) {
+			g_set_error (error,
+				     G_IO_ERROR,
+				     G_IO_ERROR_FAILED,
+				     "mismatched device bus: %s != %s",
+				     device_bus, qmi_device_bus);
+			return FALSE;
+		}
 	}
 
 	/* if no device sysfs file, error out */
-	if (device_sysfs_path == NULL) {
+	if (device_sysfs_path == NULL || device_bus == NULL) {
 		g_set_error_literal (error,
 				     FWUPD_ERROR,
 				     FWUPD_ERROR_NOT_SUPPORTED,
-				     "failed to find device sysfs path");
+				     "failed to find device details");
 		return FALSE;
 	}
 
@@ -285,15 +297,32 @@ fu_mm_device_probe_default (FuDevice *device, GError **error)
 	for (guint i = 0; device_ids[i] != NULL; i++)
 		fu_device_add_instance_id (device, device_ids[i]);
 	if (fu_device_get_vendor_ids (device) == NULL) {
-		g_autofree gchar *path = g_build_filename (device_sysfs_path, "idVendor", NULL);
-		g_autofree gchar *value = NULL;
+		g_autofree gchar *path = NULL;
+		g_autofree gchar *value_str = NULL;
 		g_autoptr(GError) error_local = NULL;
 
-		if (!g_file_get_contents (path, &value, NULL, &error_local)) {
+		if (g_strcmp0 (device_bus, "USB") == 0)
+			path = g_build_filename (device_sysfs_path, "idVendor", NULL);
+		else if (g_strcmp0 (device_bus, "PCI") == 0)
+			path = g_build_filename (device_sysfs_path, "vendor", NULL);
+
+		if (path == NULL) {
+			g_warning ("failed to set vendor ID: unsupported bus: %s", device_bus);
+		} else if (!g_file_get_contents (path, &value_str, NULL, &error_local)) {
 			g_warning ("failed to set vendor ID: %s", error_local->message);
 		} else {
-			g_autofree gchar *vendor_id = g_strdup_printf ("USB:0x%s", g_strchomp (value));
-			fu_device_add_vendor_id (device, vendor_id);
+			guint64 value_int;
+
+			/* note: the string value may be prefixed with '0x' (e.g. when reading
+			 * the PCI 'vendor' attribute, or not prefixed with anything, as in the
+			 * USB 'idVendor' attribute. */
+			value_int = g_ascii_strtoull (value_str, NULL, 16);
+			if (value_int > G_MAXUINT16) {
+				g_warning ("failed to set vendor ID: invalid value: %s", value_str);
+			} else {
+				g_autofree gchar *vendor_id = g_strdup_printf ("%s:0x%04X", device_bus, (guint) value_int);
+				fu_device_add_vendor_id (device, vendor_id);
+			}
 		}
 	}
 
diff --git a/plugins/modem-manager/fu-mm-utils.c b/plugins/modem-manager/fu-mm-utils.c
index d39f03315..86164e835 100644
--- a/plugins/modem-manager/fu-mm-utils.c
+++ b/plugins/modem-manager/fu-mm-utils.c
@@ -12,59 +12,129 @@
 
 #include "fu-mm-utils.h"
 
-gboolean
-fu_mm_utils_get_udev_port_info (GUdevDevice	 *device,
-				gchar		**out_device_sysfs_path,
-				gint		 *out_port_ifnum,
-				GError		**error)
+static gchar *
+find_device_bus_subsystem (GUdevDevice *device)
 {
-	gint port_ifnum = -1;
-	const gchar *aux;
-	g_autoptr(GUdevDevice) parent = NULL;
-	g_autofree gchar *device_sysfs_path = NULL;
+	g_autoptr(GUdevDevice) iter = NULL;
 
-	/* ID_USB_INTERFACE_NUM is set on the port device itself */
-	aux = g_udev_device_get_property (device, "ID_USB_INTERFACE_NUM");
-	if (aux != NULL)
-		port_ifnum = (guint16) g_ascii_strtoull (aux, NULL, 16);
-
-	/* we need to traverse all parents of the give udev device until we find
-	 * the first 'usb_device' reported, which is the GUdevDevice associated with
-	 * the full USB device (i.e. all ports of the same device).
-	 */
-	parent = g_udev_device_get_parent (device);
-	while (parent != NULL) {
+	iter = g_object_ref (device);
+	while (iter != NULL) {
 		g_autoptr(GUdevDevice) next = NULL;
+		const gchar *subsys;
 
-		if (g_strcmp0 (g_udev_device_get_devtype (parent), "usb_device") == 0) {
-			device_sysfs_path = g_strdup (g_udev_device_get_sysfs_path (parent));
-			break;
+		/* stop search as soon as we find a parent object
+		 * of one of the bus subsystems supported in
+		 * ModemManager */
+		subsys = g_udev_device_get_subsystem (iter);
+		if ((g_strcmp0 (subsys, "usb") == 0)      ||
+		    (g_strcmp0 (subsys, "pcmcia") == 0)   ||
+		    (g_strcmp0 (subsys, "pci") == 0)      ||
+		    (g_strcmp0 (subsys, "platform") == 0) ||
+		    (g_strcmp0 (subsys, "pnp") == 0)      ||
+		    (g_strcmp0 (subsys, "sdio") == 0)) {
+			return g_ascii_strup (subsys, -1);
 		}
 
-		/* check next parent */
-		next = g_udev_device_get_parent (parent);
-		g_set_object (&parent, next);
+		next = g_udev_device_get_parent (iter);
+		g_set_object (&iter, next);
 	}
 
-	if (parent == NULL) {
+	/* no more parents to check */
+	return NULL;
+}
+
+gboolean
+fu_mm_utils_get_udev_port_info (GUdevDevice	 *device,
+				gchar		**out_device_bus,
+				gchar		**out_device_sysfs_path,
+				gint		 *out_port_usb_ifnum,
+				GError		**error)
+{
+	gint port_usb_ifnum = -1;
+	g_autoptr(GUdevDevice) parent = NULL;
+	g_autofree gchar *device_sysfs_path = NULL;
+	g_autofree gchar *device_bus = NULL;
+
+	/* lookup the main bus the device is in; for supported devices it will
+	 * usually be either 'PCI' or 'USB' */
+	device_bus = find_device_bus_subsystem (device);
+	if (device_bus == NULL) {
 		g_set_error (error,
 			     G_IO_ERROR,
 			     G_IO_ERROR_NOT_FOUND,
-			     "failed to lookup device info: parent usb_device not found");
+			     "failed to lookup device info: bus not found");
 		return FALSE;
 	}
 
-	if (out_port_ifnum != NULL)
-		*out_port_ifnum = port_ifnum;
+	if (g_strcmp0 (device_bus, "USB") == 0) {
+		/* ID_USB_INTERFACE_NUM is set on the port device itself */
+		const gchar *aux = g_udev_device_get_property (device, "ID_USB_INTERFACE_NUM");
+		if (aux != NULL)
+			port_usb_ifnum = (guint16) g_ascii_strtoull (aux, NULL, 16);
+
+		/* we need to traverse all parents of the give udev device until we find
+		 * the first 'usb_device' reported, which is the GUdevDevice associated with
+		 * the full USB device (i.e. all ports of the same device).
+		 */
+		parent = g_udev_device_get_parent (device);
+		while (parent != NULL) {
+			g_autoptr(GUdevDevice) next = NULL;
+
+			if (g_strcmp0 (g_udev_device_get_devtype (parent), "usb_device") == 0) {
+				device_sysfs_path = g_strdup (g_udev_device_get_sysfs_path (parent));
+				break;
+			}
+
+			/* check next parent */
+			next = g_udev_device_get_parent (parent);
+			g_set_object (&parent, next);
+		}
+	} else if (g_strcmp0 (device_bus, "PCI") == 0) {
+		/* the first parent in the 'pci' subsystem is our physical device */
+		parent = g_udev_device_get_parent (device);
+		while (parent != NULL) {
+			g_autoptr(GUdevDevice) next = NULL;
+
+			if (g_strcmp0 (g_udev_device_get_subsystem (parent), "pci") == 0) {
+				device_sysfs_path = g_strdup (g_udev_device_get_sysfs_path (parent));
+				break;
+			}
+
+			/* check next parent */
+			next = g_udev_device_get_parent (parent);
+			g_set_object (&parent, next);
+		}
+	} else {
+		/* other subsystems, we don't support firmware upgrade for those */
+		g_set_error (error,
+			     G_IO_ERROR,
+			     G_IO_ERROR_NOT_SUPPORTED,
+			     "device bus unsupported: %s", device_bus);
+		return FALSE;
+	}
+
+	if (device_sysfs_path == NULL) {
+		g_set_error (error,
+			     G_IO_ERROR,
+			     G_IO_ERROR_NOT_FOUND,
+			     "failed to lookup device info: physical device not found");
+		return FALSE;
+	}
+
+	if (out_port_usb_ifnum != NULL)
+		*out_port_usb_ifnum = port_usb_ifnum;
 	if (out_device_sysfs_path != NULL)
 		*out_device_sysfs_path = g_steal_pointer (&device_sysfs_path);
+	if (out_device_bus != NULL)
+		*out_device_bus = g_steal_pointer (&device_bus);
 	return TRUE;
 }
 
 gboolean
 fu_mm_utils_get_port_info (const gchar	 *path,
+			   gchar	**out_device_bus,
 			   gchar	**out_device_sysfs_path,
-			   gint		 *out_port_ifnum,
+			   gint		 *out_port_usb_ifnum,
 			   GError	**error)
 {
 	g_autoptr(GUdevClient) client = NULL;
@@ -80,5 +150,5 @@ fu_mm_utils_get_port_info (const gchar	 *path,
 		return FALSE;
 	}
 
-	return fu_mm_utils_get_udev_port_info (dev, out_device_sysfs_path, out_port_ifnum, error);
+	return fu_mm_utils_get_udev_port_info (dev, out_device_bus, out_device_sysfs_path, out_port_usb_ifnum, error);
 }
diff --git a/plugins/modem-manager/fu-mm-utils.h b/plugins/modem-manager/fu-mm-utils.h
index e0126337e..a4ddd12ab 100644
--- a/plugins/modem-manager/fu-mm-utils.h
+++ b/plugins/modem-manager/fu-mm-utils.h
@@ -11,12 +11,14 @@
 #include <gudev/gudev.h>
 
 gboolean	fu_mm_utils_get_udev_port_info	(GUdevDevice	 *dev,
+						 gchar		**device_bus,
 						 gchar		**device_sysfs_path,
-						 gint		 *port_ifnum,
+						 gint		 *port_usb_ifnum,
 						 GError		**error);
 gboolean	fu_mm_utils_get_port_info	(const gchar	 *path,
+						 gchar		**device_bus,
 						 gchar		**device_sysfs_path,
-						 gint		 *port_ifnum,
+						 gint		 *port_usb_ifnum,
 						 GError		**error);
 
 #endif /* __FU_MM_UTILS_H */
diff --git a/plugins/modem-manager/fu-plugin-modem-manager.c b/plugins/modem-manager/fu-plugin-modem-manager.c
index 514f1b0bf..4b8c43547 100644
--- a/plugins/modem-manager/fu-plugin-modem-manager.c
+++ b/plugins/modem-manager/fu-plugin-modem-manager.c
@@ -149,23 +149,24 @@ fu_plugin_mm_udev_uevent_cb (GUdevClient	*udev,
 	const gchar *name = g_udev_device_get_name (device);
 	g_autofree gchar *path = NULL;
 	g_autofree gchar *device_sysfs_path = NULL;
+	g_autofree gchar *device_bus = NULL;
 	gint ifnum = -1;
 
 	if (action == NULL || subsystem == NULL || priv->inhibited == NULL || name == NULL)
 		return TRUE;
 
 	/* ignore if loading port info fails */
-	if (!fu_mm_utils_get_udev_port_info (device, &device_sysfs_path, &ifnum, NULL))
+	if (!fu_mm_utils_get_udev_port_info (device, &device_bus, &device_sysfs_path, &ifnum, NULL))
+		return TRUE;
+
+	/* ignore non-USB and non-PCI events */
+	if (g_strcmp0 (device_bus, "USB") != 0 && g_strcmp0 (device_bus, "PCI") != 0)
 		return TRUE;
 
 	/* ignore all events for ports not owned by our device */
 	if (g_strcmp0 (device_sysfs_path, priv->inhibited->physical_id) != 0)
 		return TRUE;
 
-	/* ignore non-cdc-wdm usbmisc ports */
-	if (g_str_equal (subsystem, "usbmisc") && !g_str_has_prefix (name, "cdc-wdm"))
-		return TRUE;
-
 	path = g_strdup_printf ("/dev/%s", name);
 
 	if ((g_str_equal (action, "add")) || (g_str_equal (action, "change"))) {