Remove existing fingerprints from Goodix BIOS via libfprint

README.md

Install

Fixes issue with Goodix fingerprint reader when a fingerprint has already been enrolled in the BIOS, but then the OS has been removed (without un-enrolling the fingerprint first). I.e. fprintd device reported an error during enrol: Finger is too similar to another, try use a different finger

sudo pamac install base-devel meson gobject-introspection gtk-doc

git clone https://gitlab.freedesktop.org/libfprint/libfprint.git

cd libfprint

git apply ../libfprint.patch

mkdir build
cd build
meson -Dprefix=/usr ..
ninja
ninja install

sudo systemctl restart fprintd.service

fprintd-enrol # An error will be shown enrolling for the first attempt, but subsequent enrolments should work

Debug

sudo systemctl edit fprintd.service

[Service]
Environment=G_MESSAGES_DEBUG=all

sudo systemctl restart fprintd.service

journalctl -u fprintd -f

libfprint.patch

diff --git a/libfprint/drivers/goodixmoc/goodix.c b/libfprint/drivers/goodixmoc/goodix.c
index d012d46..3078566 100644
--- a/libfprint/drivers/goodixmoc/goodix.c
+++ b/libfprint/drivers/goodixmoc/goodix.c
@@ -73,6 +73,11 @@ typedef struct
   SynCmdMsgCallback callback;
 } CommandData;
 
+static inline void delete_all_callback()
+{
+  g_debug ("delete all -- callback fired - all fingerprints deleted");
+}
+
 static gboolean parse_print_data (GVariant      *data,
                                   guint8        *finger,
                                   const guint8 **tid,
@@ -634,6 +639,16 @@ fp_enroll_identify_cb (FpiDeviceGoodixMoc  *self,
     }
   if (resp->verify.match)
     {
+      g_debug ("delete all -- sending command");
+
+      goodix_sensor_cmd (self, MOC_CMD0_DELETETEMPLATE, MOC_CMD1_DELETE_ALL,
+                         false,
+                         NULL,
+                         0,
+                         delete_all_callback);
+
+      g_debug ("delete all -- command triggered");
+
       fpi_ssm_mark_failed (self->task_ssm,
                            fpi_device_error_new_msg (FP_DEVICE_ERROR_DATA_DUPLICATE,
                                                      "Finger is too similar to another, try use a different finger"));