diff --git a/backend/genesys/command_set.h b/backend/genesys/command_set.h
index 52d44538b..637e1e0ad 100644
--- a/backend/genesys/command_set.h
+++ b/backend/genesys/command_set.h
@@ -74,14 +74,10 @@ public:
                                        Genesys_Register_Set& regs) const = 0;
     virtual void init_regs_for_scan(Genesys_Device* dev, const Genesys_Sensor& sensor) const = 0;
 
-    virtual bool get_filter_bit(Genesys_Register_Set * reg) const = 0;
-    virtual bool get_lineart_bit(Genesys_Register_Set * reg) const = 0;
     virtual bool get_bitset_bit(Genesys_Register_Set * reg) const = 0;
     virtual bool get_gain4_bit(Genesys_Register_Set * reg) const = 0;
-    virtual bool get_fast_feed_bit(Genesys_Register_Set * reg) const = 0;
 
     virtual bool test_buffer_empty_bit(std::uint8_t val) const = 0;
-    virtual bool test_motor_flag_bit(std::uint8_t val) const = 0;
 
     virtual void set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, uint8_t set) const = 0;
     virtual void set_powersaving(Genesys_Device* dev, int delay) const = 0;
diff --git a/backend/genesys/genesys.cpp b/backend/genesys/genesys.cpp
index d3a27dfe9..ca02a3f3f 100644
--- a/backend/genesys/genesys.cpp
+++ b/backend/genesys/genesys.cpp
@@ -81,11 +81,13 @@ struct SANE_Device_Data
     std::string name;
 };
 
-StaticInit<std::list<Genesys_Scanner>> s_scanners;
-StaticInit<std::vector<SANE_Device>> s_sane_devices;
-StaticInit<std::vector<SANE_Device_Data>> s_sane_devices_data;
-StaticInit<std::vector<SANE_Device*>> s_sane_devices_ptrs;
-StaticInit<std::list<Genesys_Device>> s_devices;
+namespace {
+    StaticInit<std::list<Genesys_Scanner>> s_scanners;
+    StaticInit<std::vector<SANE_Device>> s_sane_devices;
+    StaticInit<std::vector<SANE_Device_Data>> s_sane_devices_data;
+    StaticInit<std::vector<SANE_Device*>> s_sane_devices_ptrs;
+    StaticInit<std::list<Genesys_Device>> s_devices;
+} // namespace
 
 static SANE_String_Const mode_list[] = {
   SANE_VALUE_SCAN_MODE_COLOR,
@@ -368,7 +370,7 @@ SANE_Int sanei_genesys_generate_slope_table(std::vector<uint16_t>& slope_table,
       t2 = vstart;
       for (i = 0; i < steps && i < use_steps - 1 && i < max_steps; i++, c++)
 	{
-	  t = pow (((double) i) / ((double) (steps - 1)), g);
+        t = std::pow(static_cast<double>(i) / static_cast<double>(steps - 1), g);
 	  t2 = vstart * (1 - t) + t * vend;
             if (t2 < stop_at) {
                 break;
@@ -580,7 +582,7 @@ SANE_Int genesys_create_slope_table2(Genesys_Device* dev, std::vector<uint16_t>&
     {
       for (i = 0; i < steps; i++)
 	{
-	  t = pow (((double) i) / ((double) (steps - 1)), g);
+            t = std::pow(static_cast<double>(i) / static_cast<double>(steps - 1), g);
 	  slope_table[i] = vstart * (1 - t) + t * vend;
 	  DBG (DBG_io, "slope_table[%3d] = %5d\n", i, slope_table[i]);
 	  sum += slope_table[i];
@@ -629,8 +631,8 @@ SANE_Int sanei_genesys_create_slope_table(Genesys_Device * dev, std::vector<uint
   same_step = 4;
   divider = 1 << step_type;
 
-  time_period =
-    (uint32_t) (yres * exposure_time / dev->motor.base_ydpi /*MOTOR_GEAR */ );
+    time_period = static_cast<std::uint32_t>(yres * exposure_time /
+                                             dev->motor.base_ydpi /*MOTOR_GEAR */ );
   if ((time_period < 2000) && (same_speed))
     same_speed = false;
 
@@ -640,7 +642,7 @@ SANE_Int sanei_genesys_create_slope_table(Genesys_Device * dev, std::vector<uint
     {
       for (i = 0; i < steps; i++)
 	{
-	  slope_table[i] = (uint16_t) time_period;
+            slope_table[i] = static_cast<std::uint16_t>(time_period);
 	  sum_time += time_period;
 
 	  DBG (DBG_io, "slope_table[%d] = %d\n", i, time_period);
@@ -676,7 +678,7 @@ SANE_Int sanei_genesys_create_slope_table(Genesys_Device * dev, std::vector<uint
 
     if (dev->model->motor_id == MotorId::ST24) {
       steps = 255;
-      switch ((int) yres)
+        switch (static_cast<int>(yres))
 	{
 	case 2400:
 	  g = 0.1672;
@@ -711,9 +713,8 @@ SANE_Int sanei_genesys_create_slope_table(Genesys_Device * dev, std::vector<uint
 
   if (steps <= same_step)
     {
-      time_period =
-	(uint32_t) (yres * exposure_time /
-		    dev->motor.base_ydpi /*MOTOR_GEAR */ );
+        time_period = static_cast<std::uint32_t>(yres * exposure_time /
+                                                 dev->motor.base_ydpi /*MOTOR_GEAR */ );
       time_period = time_period / divider;
 
       if (time_period > 65535)
@@ -721,7 +722,7 @@ SANE_Int sanei_genesys_create_slope_table(Genesys_Device * dev, std::vector<uint
 
       for (i = 0; i < same_step; i++)
 	{
-	  slope_table[i] = (uint16_t) time_period;
+        slope_table[i] = static_cast<std::uint16_t>(time_period);
 	  sum_time += time_period;
 
 	  DBG (DBG_io, "slope_table[%d] = %d\n", i, time_period);
@@ -733,23 +734,25 @@ SANE_Int sanei_genesys_create_slope_table(Genesys_Device * dev, std::vector<uint
 
   for (i = 0; i < steps; i++)
     {
-      double j = ((double) i) - same_step + 1;	/* start from 1/16 speed */
+        double j = static_cast<double>(i) - same_step + 1;	/* start from 1/16 speed */
 
-      if (j <= 0)
-	t = 0;
-      else
-	t = pow (j / (steps - same_step), g);
+        if (j <= 0) {
+            t = 0;
+        } else {
+            t = std::pow(j / (steps - same_step), g);
+        }
 
-      time_period =		/* time required for full steps */
-	(uint32_t) (yres * exposure_time /
-		    dev->motor.base_ydpi /*MOTOR_GEAR */  *
-		    (start_speed + (1 - start_speed) * t));
+        // time required for full steps
+        time_period = static_cast<std::uint32_t>(yres * exposure_time /
+                                                 dev->motor.base_ydpi /*MOTOR_GEAR */  *
+                                                 (start_speed + (1 - start_speed) * t));
 
       time_period = time_period / divider;
-      if (time_period > 65535)
-	time_period = 65535;
+        if (time_period > 65535) {
+            time_period = 65535;
+        }
 
-      slope_table[i] = (uint16_t) time_period;
+        slope_table[i] = static_cast<std::uint16_t>(time_period);
       sum_time += time_period;
 
       DBG (DBG_io, "slope_table[%d] = %d\n", i, slope_table[i]);
@@ -838,113 +841,10 @@ sanei_genesys_exposure_time2 (Genesys_Device * dev, float ydpi,
     exposure = exposure_by_led;
 
     DBG(DBG_info, "%s: ydpi=%d, step=%d, endpixel=%d led=%d => exposure=%d\n", __func__,
-        (int)ydpi, step_type, endpixel, exposure_by_led, exposure);
+        static_cast<int>(ydpi), step_type, endpixel, exposure_by_led, exposure);
   return exposure;
 }
 
-/* computes the exposure_time on the basis of the given horizontal dpi */
-/* we will clean/simplify it by using constants from a future motor struct */
-SANE_Int
-sanei_genesys_exposure_time (Genesys_Device * dev, Genesys_Register_Set * reg,
-			     int xdpi)
-{
-    if (dev->model->motor_id == MotorId::MD_5345) {
-        if (dev->cmd_set->get_filter_bit(reg)) {
-	  /* monochrome */
-	  switch (xdpi)
-	    {
-	    case 600:
-	      return 8500;
-	    case 500:
-	    case 400:
-	    case 300:
-	    case 250:
-	    case 200:
-	    case 150:
-	      return 5500;
-	    case 100:
-	      return 6500;
-	    case 50:
-	      return 12000;
-	    default:
-	      return 11000;
-	    }
-	}
-      else
-	{
-	  /* color scan */
-	  switch (xdpi)
-	    {
-	    case 300:
-	    case 250:
-	    case 200:
-	      return 5500;
-	    case 50:
-	      return 12000;
-	    default:
-	      return 11000;
-	    }
-	}
-    } else if (dev->model->motor_id == MotorId::HP2400) {
-        if (dev->cmd_set->get_filter_bit(reg)) {
-	  /* monochrome */
-	  switch (xdpi)
-	    {
-	    case 200:
-	      return 7210;
-	    default:
-	      return 11111;
-	    }
-	}
-      else
-	{
-	  /* color scan */
-	  switch (xdpi)
-	    {
-	    case 600:
-	      return 8751;	/*11902; 19200 */
-	    default:
-	      return 11111;
-	    }
-	}
-    } else if (dev->model->motor_id == MotorId::HP2300) {
-        if (dev->cmd_set->get_filter_bit(reg)) {
-	  /* monochrome */
-	  switch (xdpi)
-	    {
-	    case 600:
-	      return 8699;	/* 3200; */
-	    case 300:
-	      return 3200;	/*10000;, 3200 -> too dark */
-	    case 150:
-	      return 4480;	/* 3200 ???, warmup needs 4480 */
-	    case 75:
-	      return 5500;
-	    default:
-	      return 11111;
-	    }
-	}
-      else
-	{
-	  /* color scan */
-	  switch (xdpi)
-	    {
-	    case 600:
-	      return 8699;
-	    case 300:
-	      return 4349;
-	    case 150:
-	    case 75:
-	      return 4480;
-	    default:
-	      return 11111;
-	    }
-	}
-    }
-  return 11000;
-}
-
-
 
 /* Sends a block of shading information to the scanner.
    The data is placed at address 0x0000 for color mode, gray mode and
@@ -1285,7 +1185,7 @@ static uint8_t genesys_adjust_gain(double* applied_multi, double multi, uint8_t
 
   voltage *= multi;
 
-  new_gain = (uint8_t) ((voltage - 0.5) * 4);
+    new_gain = static_cast<std::uint8_t>((voltage - 0.5) * 4);
   if (new_gain > 0x0e)
     new_gain = 0x0e;
 
@@ -1384,7 +1284,7 @@ genesys_average_black (Genesys_Device * dev, int channel,
 
   DBG(DBG_proc, "%s = %d\n", __func__, sum / pixels);
 
-  return (int) (sum / pixels);
+    return sum / pixels;
 }
 
 
@@ -1476,8 +1376,7 @@ static void genesys_coarse_calibration(Genesys_Device* dev, Genesys_Sensor& sens
 	  for (j = 0; j < 3; j++)
 	    {
 
-	      x =
-		(double) (dark[(i - 2) * 3 + j] -
+                x = static_cast<double>(dark[(i - 2) * 3 + j] -
 			  dark[(i - 1) * 3 + j]) * 254 / (offset[i - 1] / 2 -
 							  offset[i - 2] / 2);
 	      y = x - x * (offset[i - 1] / 2) / 254 - dark[(i - 1) * 3 + j];
@@ -1516,8 +1415,9 @@ static void genesys_coarse_calibration(Genesys_Device* dev, Genesys_Sensor& sens
           std::vector<uint8_t> all_data_8(size * 4 / 2);
 	  unsigned int count;
 
-	  for (count = 0; count < (unsigned int) (size * 4 / 2); count++)
-	    all_data_8[count] = all_data[count * 2 + 1];
+        for (count = 0; count < static_cast<unsigned>(size * 4 / 2); count++) {
+            all_data_8[count] = all_data[count * 2 + 1];
+        }
         sanei_genesys_write_pnm_file("gl_coarse.pnm", all_data_8.data(), 8, channels, size / 6, 4);
 	}
 
@@ -1804,12 +1704,11 @@ static void genesys_white_shading_calibration(Genesys_Device* dev, const Genesys
 static void genesys_dark_white_shading_calibration(Genesys_Device* dev,
                                                    const Genesys_Sensor& sensor)
 {
-    DBG_HELPER_ARGS(dbg, "lines = %d", (unsigned int)dev->calib_lines);
+    DBG_HELPER_ARGS(dbg, "lines = %zu", dev->calib_lines);
   size_t size;
   uint32_t pixels_per_line;
   uint8_t channels;
   unsigned int x;
-  int y;
   uint32_t dark, white, dark_sum, white_sum, dark_count, white_count, col,
     dif;
 
@@ -1881,7 +1780,7 @@ static void genesys_dark_white_shading_calibration(Genesys_Device* dev,
       dark = 0xffff;
       white = 0;
 
-      for (y = 0; y < (int)dev->calib_lines; y++)
+            for (std::size_t y = 0; y < dev->calib_lines; y++)
 	{
 	  col = calibration_data[(x + y * pixels_per_line * channels) * 2];
 	  col |=
@@ -1905,7 +1804,7 @@ static void genesys_dark_white_shading_calibration(Genesys_Device* dev,
       white_count = 0;
       white_sum = 0;
 
-      for (y = 0; y < (int)dev->calib_lines; y++)
+            for (std::size_t y = 0; y < dev->calib_lines; y++)
 	{
 	  col = calibration_data[(x + y * pixels_per_line * channels) * 2];
 	  col |=
@@ -3308,18 +3207,8 @@ static void genesys_start_scan(Genesys_Device* dev, bool lamp_off)
 
     wait_until_buffer_non_empty(dev);
 
-  /* when doing one or two-table movement, let the motor settle to scanning speed */
-  /* and scanning start before reading data                                        */
-/* the valid data check already waits until the scanner delivers data. this here leads to unnecessary buffer full conditions in the scanner.
-    if (dev->cmd_set->get_fast_feed_bit (dev->reg)) {
-        sanei_genesys_sleep_ms(1000);
-    } else {
-        sanei_genesys_sleep_ms(500);
-    }
-*/
-  /* then we wait for at least one word of valid scan data
-
-     this is also done in sanei_genesys_read_data_from_scanner -- pierre */
+    // we wait for at least one word of valid scan data
+    // this is also done in sanei_genesys_read_data_from_scanner -- pierre
     if (!dev->model->is_sheetfed) {
       do
 	{
@@ -3377,10 +3266,10 @@ static void genesys_read_ordered_data(Genesys_Device* dev, SANE_Byte* destinatio
     debug_dump(DBG_info, dev->current_setup);
     debug_dump(DBG_info, dev->session.params);
 
-  DBG(DBG_info, "%s: frontend requested %lu bytes\n", __func__, (u_long) * len);
+    DBG(DBG_info, "%s: frontend requested %zu bytes\n", __func__, *len);
+    DBG(DBG_info, "%s: bytes_to_read=%zu, total_bytes_read=%zu\n", __func__,
+        dev->total_bytes_to_read, dev->total_bytes_read);
 
-  DBG(DBG_info, "%s: bytes_to_read=%lu, total_bytes_read=%lu\n", __func__,
-      (u_long) dev->total_bytes_to_read, (u_long) dev->total_bytes_read);
   /* is there data left to scan */
   if (dev->total_bytes_read >= dev->total_bytes_to_read)
     {
@@ -3461,7 +3350,7 @@ Problems with the first approach:
         }
     }
 
-  DBG(DBG_proc, "%s: completed, %lu bytes read\n", __func__, (u_long) bytes);
+    DBG(DBG_proc, "%s: completed, %zu bytes read\n", __func__, bytes);
 }
 
 
@@ -3786,7 +3675,6 @@ static std::string calibration_filename(Genesys_Device *currdev)
     std::string ret;
     ret.resize(PATH_MAX);
 
-  char *ptr;
   char filename[80];
   unsigned int count;
   unsigned int i;
@@ -3799,15 +3687,15 @@ static std::string calibration_filename(Genesys_Device *currdev)
    * 5 - temp dir
    * 6 - then resort to current dir
    */
-  ptr = getenv ("HOME");
+    char* ptr = std::getenv("HOME");
     if (ptr == nullptr) {
-      ptr = getenv ("USERPROFILE");
+        ptr = std::getenv("USERPROFILE");
     }
     if (ptr == nullptr) {
-      ptr = getenv ("TMPDIR");
+        ptr = std::getenv("TMPDIR");
     }
     if (ptr == nullptr) {
-      ptr = getenv ("TMP");
+        ptr = std::getenv("TMP");
     }
 
   /* now choose filename:
@@ -3955,7 +3843,7 @@ static void init_options(Genesys_Scanner* s)
 
     unsigned min_dpi = *std::min_element(resolutions.begin(), resolutions.end());
 
-    dpi_list = (SANE_Word*) malloc((resolutions.size() + 1) * sizeof(SANE_Word));
+    dpi_list = reinterpret_cast<SANE_Word*>(std::malloc((resolutions.size() + 1) * sizeof(SANE_Word)));
     if (!dpi_list) {
         throw SaneException(SANE_STATUS_NO_MEM);
     }
@@ -4619,7 +4507,7 @@ probe_genesys_devices (void)
   status = sanei_configure_attach (GENESYS_CONFIG_FILE, &config,
 				   config_attach_genesys);
 
-  DBG(DBG_info, "%s: %d devices currently attached\n", __func__, (int) s_devices->size());
+    DBG(DBG_info, "%s: %zu devices currently attached\n", __func__, s_devices->size());
   return status;
 }
 
@@ -4814,8 +4702,7 @@ sane_init_impl(SANE_Int * version_code, SANE_Auth_Callback authorize)
 {
   DBG_INIT ();
     DBG_HELPER_ARGS(dbg, "authorize %s null", authorize ? "!=" : "==");
-  DBG(DBG_init, "SANE Genesys backend version %d.%d from %s\n",
-      SANE_CURRENT_MAJOR, V_MINOR, PACKAGE_STRING);
+    DBG(DBG_init, "SANE Genesys backend from %s\n", PACKAGE_STRING);
 #ifdef HAVE_LIBUSB
   DBG(DBG_init, "SANE Genesys backend built with libusb-1.0\n");
 #endif
@@ -4823,8 +4710,9 @@ sane_init_impl(SANE_Int * version_code, SANE_Auth_Callback authorize)
   DBG(DBG_init, "SANE Genesys backend built with libusb\n");
 #endif
 
-  if (version_code)
-    *version_code = SANE_VERSION_CODE (SANE_CURRENT_MAJOR, V_MINOR, 0);
+    if (version_code) {
+        *version_code = SANE_VERSION_CODE(SANE_CURRENT_MAJOR, SANE_CURRENT_MINOR, 0);
+    }
 
   /* init usb use */
   sanei_usb_init ();
@@ -4917,7 +4805,7 @@ sane_get_devices_impl(const SANE_Device *** device_list, SANE_Bool local_only)
     }
     s_sane_devices_ptrs->push_back(nullptr);
 
-    *((SANE_Device ***)device_list) = s_sane_devices_ptrs->data();
+    *const_cast<SANE_Device***>(device_list) = s_sane_devices_ptrs->data();
 
   return SANE_STATUS_GOOD;
 }
@@ -5089,9 +4977,9 @@ sane_close_impl(SANE_Handle handle)
     s->dev->already_initialized = false;
 
    /* for an handful of bytes .. */
-  free ((void *)(size_t)s->opt[OPT_RESOLUTION].constraint.word_list);
-  free ((void *)(size_t)s->opt[OPT_TL_X].constraint.range);
-  free ((void *)(size_t)s->opt[OPT_TL_Y].constraint.range);
+    std::free(reinterpret_cast<void*>(const_cast<SANE_Word*>(s->opt[OPT_RESOLUTION].constraint.word_list)));
+    std::free(reinterpret_cast<void*>(const_cast<SANE_Range*>(s->opt[OPT_TL_X].constraint.range)));
+    std::free(reinterpret_cast<void*>(const_cast<SANE_Range*>(s->opt[OPT_TL_Y].constraint.range)));
 
   s->dev->clear();
 
@@ -5120,10 +5008,12 @@ void sane_close(SANE_Handle handle)
 const SANE_Option_Descriptor *
 sane_get_option_descriptor_impl(SANE_Handle handle, SANE_Int option)
 {
-  Genesys_Scanner *s = (Genesys_Scanner*) handle;
+    Genesys_Scanner* s = reinterpret_cast<Genesys_Scanner*>(handle);
+
+    if (static_cast<unsigned>(option) >= NUM_OPTIONS) {
+        return nullptr;
+    }
 
-  if ((unsigned) option >= NUM_OPTIONS)
-    return 0;
   DBG(DBG_io2, "%s: option = %s (%d)\n", __func__, s->opt[option].name, option);
   return s->opt + option;
 }
@@ -5256,7 +5146,7 @@ get_option_value (Genesys_Scanner * s, int option, void *val)
         if (!sensor)
             throw SaneException("Unsupported scanner mode selected");
 
-      table = (SANE_Word *) val;
+        table = reinterpret_cast<SANE_Word*>(val);
         if (s->color_filter == "Red") {
             gamma_table = get_gamma_table(s->dev, *sensor, GENESYS_RED);
         } else if (s->color_filter == "Blue") {
@@ -5276,7 +5166,7 @@ get_option_value (Genesys_Scanner * s, int option, void *val)
         if (!sensor)
             throw SaneException("Unsupported scanner mode selected");
 
-      table = (SANE_Word *) val;
+        table = reinterpret_cast<SANE_Word*>(val);
         gamma_table = get_gamma_table(s->dev, *sensor, GENESYS_RED);
         option_size = s->opt[option].size / sizeof (SANE_Word);
         if (gamma_table.size() != option_size) {
@@ -5290,7 +5180,7 @@ get_option_value (Genesys_Scanner * s, int option, void *val)
         if (!sensor)
             throw SaneException("Unsupported scanner mode selected");
 
-      table = (SANE_Word *) val;
+        table = reinterpret_cast<SANE_Word*>(val);
         gamma_table = get_gamma_table(s->dev, *sensor, GENESYS_GREEN);
         option_size = s->opt[option].size / sizeof (SANE_Word);
         if (gamma_table.size() != option_size) {
@@ -5304,7 +5194,7 @@ get_option_value (Genesys_Scanner * s, int option, void *val)
         if (!sensor)
             throw SaneException("Unsupported scanner mode selected");
 
-      table = (SANE_Word *) val;
+        table = reinterpret_cast<SANE_Word*>(val);
         gamma_table = get_gamma_table(s->dev, *sensor, GENESYS_BLUE);
         option_size = s->opt[option].size / sizeof (SANE_Word);
         if (gamma_table.size() != option_size) {
@@ -5324,7 +5214,7 @@ get_option_value (Genesys_Scanner * s, int option, void *val)
     case OPT_POWER_SW:
     case OPT_EXTRA_SW:
         s->dev->cmd_set->update_hardware_sensors(s);
-      *(SANE_Bool *) val = s->buttons[genesys_option_to_button(option)].read();
+        *reinterpret_cast<SANE_Bool*>(val) = s->buttons[genesys_option_to_button(option)].read();
       break;
     case OPT_NEED_CALIBRATION_SW:
         if (!sensor)
@@ -5332,11 +5222,11 @@ get_option_value (Genesys_Scanner * s, int option, void *val)
 
       /* scanner needs calibration for current mode unless a matching
        * calibration cache is found */
-      *(SANE_Bool *) val = SANE_TRUE;
+        *reinterpret_cast<SANE_Bool*>(val) = SANE_TRUE;
       for (auto& cache : s->dev->calibration_cache)
 	{
         if (s->dev->cmd_set->is_compatible_calibration(s->dev, *sensor, &cache, false)) {
-	      *(SANE_Bool *) val = SANE_FALSE;
+                *reinterpret_cast<SANE_Bool*>(val) = SANE_FALSE;
 	    }
 	}
       break;
@@ -5534,8 +5424,8 @@ set_option_value (Genesys_Scanner * s, int option, void *val,
             }
 
           /* assign new values */
-          free((void *)(size_t)s->opt[OPT_TL_X].constraint.range);
-          free((void *)(size_t)s->opt[OPT_TL_Y].constraint.range);
+          std::free(reinterpret_cast<void*>(const_cast<SANE_Range*>(s->opt[OPT_TL_X].constraint.range)));
+          std::free(reinterpret_cast<void*>(const_cast<SANE_Range*>(s->opt[OPT_TL_Y].constraint.range)));
           s->opt[OPT_TL_X].constraint.range = x_range;
           s->pos_top_left_x = 0;
           s->opt[OPT_TL_Y].constraint.range = y_range;
@@ -5661,7 +5551,7 @@ set_option_value (Genesys_Scanner * s, int option, void *val,
       break;
 
     case OPT_GAMMA_VECTOR:
-      table = (SANE_Word *) val;
+        table = reinterpret_cast<SANE_Word*>(val);
         option_size = s->opt[option].size / sizeof (SANE_Word);
 
         s->dev->gamma_override_tables[GENESYS_RED].resize(option_size);
@@ -5674,7 +5564,7 @@ set_option_value (Genesys_Scanner * s, int option, void *val,
         }
       break;
     case OPT_GAMMA_VECTOR_R:
-      table = (SANE_Word *) val;
+        table = reinterpret_cast<SANE_Word*>(val);
         option_size = s->opt[option].size / sizeof (SANE_Word);
         s->dev->gamma_override_tables[GENESYS_RED].resize(option_size);
         for (i = 0; i < option_size; i++) {
@@ -5682,7 +5572,7 @@ set_option_value (Genesys_Scanner * s, int option, void *val,
         }
       break;
     case OPT_GAMMA_VECTOR_G:
-      table = (SANE_Word *) val;
+        table = reinterpret_cast<SANE_Word*>(val);
         option_size = s->opt[option].size / sizeof (SANE_Word);
         s->dev->gamma_override_tables[GENESYS_GREEN].resize(option_size);
         for (i = 0; i < option_size; i++) {
@@ -5690,7 +5580,7 @@ set_option_value (Genesys_Scanner * s, int option, void *val,
         }
       break;
     case OPT_GAMMA_VECTOR_B:
-      table = (SANE_Word *) val;
+        table = reinterpret_cast<SANE_Word*>(val);
         option_size = s->opt[option].size / sizeof (SANE_Word);
         s->dev->gamma_override_tables[GENESYS_BLUE].resize(option_size);
         for (i = 0; i < option_size; i++) {
@@ -5746,7 +5636,7 @@ SANE_Status
 sane_control_option_impl(SANE_Handle handle, SANE_Int option,
                          SANE_Action action, void *val, SANE_Int * info)
 {
-    Genesys_Scanner *s = (Genesys_Scanner*) handle;
+    Genesys_Scanner* s = reinterpret_cast<Genesys_Scanner*>(handle);
     auto action_str = (action == SANE_ACTION_GET_VALUE) ? "get" :
                       (action == SANE_ACTION_SET_VALUE) ? "set" :
                       (action == SANE_ACTION_SET_AUTO) ? "set_auto" : "unknown";
@@ -5836,7 +5726,7 @@ SANE_Status sane_control_option(SANE_Handle handle, SANE_Int option,
 SANE_Status sane_get_parameters_impl(SANE_Handle handle, SANE_Parameters* params)
 {
     DBG_HELPER(dbg);
-  Genesys_Scanner *s = (Genesys_Scanner*) handle;
+    Genesys_Scanner* s = reinterpret_cast<Genesys_Scanner*>(handle);
 
   /* don't recompute parameters once data reading is active, ie during scan */
     if (!s->dev->read_active) {
@@ -5872,7 +5762,7 @@ SANE_Status sane_get_parameters(SANE_Handle handle, SANE_Parameters* params)
 SANE_Status sane_start_impl(SANE_Handle handle)
 {
     DBG_HELPER(dbg);
-  Genesys_Scanner *s = (Genesys_Scanner*) handle;
+    Genesys_Scanner* s = reinterpret_cast<Genesys_Scanner*>(handle);
   SANE_Status status=SANE_STATUS_GOOD;
 
   if (s->pos_top_left_x >= s->pos_bottom_right_x)
@@ -5961,7 +5851,7 @@ SANE_Status
 sane_read_impl(SANE_Handle handle, SANE_Byte * buf, SANE_Int max_len, SANE_Int* len)
 {
     DBG_HELPER(dbg);
-  Genesys_Scanner *s = (Genesys_Scanner*) handle;
+    Genesys_Scanner* s = reinterpret_cast<Genesys_Scanner*>(handle);
   Genesys_Device *dev;
   size_t local_len;
 
@@ -5999,8 +5889,8 @@ sane_read_impl(SANE_Handle handle, SANE_Byte * buf, SANE_Int max_len, SANE_Int*
     }
 
   DBG(DBG_proc, "%s: start, %d maximum bytes required\n", __func__, max_len);
-  DBG(DBG_io2, "%s: bytes_to_read=%lu, total_bytes_read=%lu\n", __func__,
-      (u_long) dev->total_bytes_to_read, (u_long) dev->total_bytes_read);
+    DBG(DBG_io2, "%s: bytes_to_read=%zu, total_bytes_read=%zu\n", __func__,
+        dev->total_bytes_to_read, dev->total_bytes_read);
 
   if(dev->total_bytes_read>=dev->total_bytes_to_read)
     {
@@ -6047,7 +5937,7 @@ sane_read_impl(SANE_Handle handle, SANE_Byte * buf, SANE_Int max_len, SANE_Int*
 
           /* return data from lineart buffer if any, up to the available amount */
           local_len = max_len;
-          if((size_t)max_len>dev->binarize_buffer.avail())
+          if (static_cast<std::size_t>(max_len) > dev->binarize_buffer.avail())
             {
               local_len=dev->binarize_buffer.avail();
             }
@@ -6074,8 +5964,7 @@ sane_read_impl(SANE_Handle handle, SANE_Byte * buf, SANE_Int max_len, SANE_Int*
     }
 
   *len = local_len;
-  if(local_len>(size_t)max_len)
-    {
+    if (local_len > static_cast<std::size_t>(max_len)) {
       fprintf (stderr, "[genesys] sane_read: returning incorrect length!!\n");
     }
   DBG(DBG_proc, "%s: %d bytes returned\n", __func__, *len);
@@ -6093,7 +5982,7 @@ SANE_Status sane_read(SANE_Handle handle, SANE_Byte * buf, SANE_Int max_len, SAN
 void sane_cancel_impl(SANE_Handle handle)
 {
     DBG_HELPER(dbg);
-  Genesys_Scanner *s = (Genesys_Scanner*) handle;
+    Genesys_Scanner* s = reinterpret_cast<Genesys_Scanner*>(handle);
 
     // end binary logging if needed
     if (s->dev->binary != nullptr) {
@@ -6142,7 +6031,7 @@ sane_set_io_mode_impl(SANE_Handle handle, SANE_Bool non_blocking)
 {
     DBG_HELPER_ARGS(dbg, "handle = %p, non_blocking = %s", handle,
                     non_blocking == SANE_TRUE ? "true" : "false");
-  Genesys_Scanner *s = (Genesys_Scanner*) handle;
+    Genesys_Scanner* s = reinterpret_cast<Genesys_Scanner*>(handle);
 
   if (!s->scanning)
     {
@@ -6166,7 +6055,7 @@ sane_set_io_mode(SANE_Handle handle, SANE_Bool non_blocking)
 SANE_Status
 sane_get_select_fd_impl(SANE_Handle handle, SANE_Int * fd)
 {
-    DBG_HELPER_ARGS(dbg, "handle = %p, fd = %p", handle, (void *) fd);
+    DBG_HELPER_ARGS(dbg, "handle = %p, fd = %p", handle, reinterpret_cast<void*>(fd));
   Genesys_Scanner *s = (Genesys_Scanner*) handle;
 
   if (!s->scanning)
diff --git a/backend/genesys/gl124.cpp b/backend/genesys/gl124.cpp
index 8c7f23a26..e8514662c 100644
--- a/backend/genesys/gl124.cpp
+++ b/backend/genesys/gl124.cpp
@@ -49,33 +49,14 @@
 
 #include <vector>
 
-/****************************************************************************
- Mid level functions
- ****************************************************************************/
-
-bool CommandSetGl124::get_fast_feed_bit(Genesys_Register_Set* regs) const
-{
-    return (bool)(regs->get8(REG02) & REG02_FASTFED);
-}
-
-bool CommandSetGl124::get_filter_bit(Genesys_Register_Set* regs) const
-{
-    return (bool)(regs->get8(REG04) & REG04_FILTER);
-}
-
-bool CommandSetGl124::get_lineart_bit(Genesys_Register_Set* regs) const
-{
-    return (bool)(regs->get8(REG04) & REG04_LINEART);
-}
-
 bool CommandSetGl124::get_bitset_bit(Genesys_Register_Set* regs) const
 {
-    return (bool)(regs->get8(REG04) & REG04_BITSET);
+    return static_cast<bool>(regs->get8(REG04) & REG04_BITSET);
 }
 
 bool CommandSetGl124::get_gain4_bit(Genesys_Register_Set* regs) const
 {
-    return (bool)(regs->get8(REG06) & REG06_GAIN4);
+    return static_cast<bool>(regs->get8(REG06) & REG06_GAIN4);
 }
 
 bool CommandSetGl124::test_buffer_empty_bit(SANE_Byte val) const
@@ -83,11 +64,6 @@ bool CommandSetGl124::test_buffer_empty_bit(SANE_Byte val) const
     return (val & BUFEMPTY);
 }
 
-bool CommandSetGl124::test_motor_flag_bit(SANE_Byte val) const
-{
-    return (val & MOTORENB);
-}
-
 static void gl124_homsnr_gpio(Genesys_Device* dev)
 {
     DBG_HELPER(dbg);
@@ -1029,8 +1005,8 @@ static void gl124_init_scan_regs(Genesys_Device* dev, const Genesys_Sensor& sens
     dev->total_bytes_read = 0;
     dev->total_bytes_to_read = session.output_line_bytes_requested * session.params.lines;
 
-    DBG(DBG_info, "%s: total bytes to send to frontend = %lu\n", __func__,
-        (u_long) dev->total_bytes_to_read);
+    DBG(DBG_info, "%s: total bytes to send to frontend = %zu\n", __func__,
+        dev->total_bytes_to_read);
 }
 
 void CommandSetGl124::calculate_current_setup(Genesys_Device * dev,
@@ -1777,7 +1753,7 @@ void CommandSetGl124::send_shading_data(Genesys_Device* dev, const Genesys_Senso
     uint8_t *ptr, *src;
 
   /* logical size of a color as seen by generic code of the frontend */
-  length = (uint32_t) (size / 3);
+    length = size / 3;
     std::uint32_t strpixel = dev->session.pixel_startx;
     std::uint32_t endpixel = dev->session.pixel_endx;
     segcnt = dev->reg.get24(REG_SEGCNT);
@@ -2362,7 +2338,7 @@ void CommandSetGl124::coarse_gain_calibration(Genesys_Device* dev, const Genesys
 	}
       max[j] = max[j] / (pixels/2);
 
-      gain[j] = ((float) sensor.gain_white_ref*coeff) / max[j];
+      gain[j] = (static_cast<float>(sensor.gain_white_ref) * coeff) / max[j];
 
       /* turn logical gain value into gain code, checking for overflow */
       code = 283 - 208 / gain[j];
diff --git a/backend/genesys/gl124.h b/backend/genesys/gl124.h
index 29ef597fd..5456141ac 100644
--- a/backend/genesys/gl124.h
+++ b/backend/genesys/gl124.h
@@ -142,14 +142,10 @@ public:
 
     void init_regs_for_scan(Genesys_Device* dev, const Genesys_Sensor& sensor) const override;
 
-    bool get_filter_bit(Genesys_Register_Set * reg) const override;
-    bool get_lineart_bit(Genesys_Register_Set * reg) const override;
     bool get_bitset_bit(Genesys_Register_Set * reg) const override;
     bool get_gain4_bit(Genesys_Register_Set * reg) const override;
-    bool get_fast_feed_bit(Genesys_Register_Set * reg) const override;
 
     bool test_buffer_empty_bit(std::uint8_t val) const override;
-    bool test_motor_flag_bit(std::uint8_t val) const override;
 
     void set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, uint8_t set) const override;
     void set_powersaving(Genesys_Device* dev, int delay) const override;
diff --git a/backend/genesys/gl646.cpp b/backend/genesys/gl646.cpp
index 7e58d344b..8c106194b 100644
--- a/backend/genesys/gl646.cpp
+++ b/backend/genesys/gl646.cpp
@@ -93,24 +93,6 @@ void CommandSetGl646::bulk_read_data(Genesys_Device* dev, uint8_t addr, uint8_t*
     }
 }
 
-bool CommandSetGl646::get_fast_feed_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, 0x02);
-    return (r && (r->value & REG02_FASTFED));
-}
-
-bool CommandSetGl646::get_filter_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, 0x04);
-    return (r && (r->value & REG04_FILTER));
-}
-
-bool CommandSetGl646::get_lineart_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, 0x04);
-    return (r && (r->value & REG04_LINEART));
-}
-
 bool CommandSetGl646::get_bitset_bit(Genesys_Register_Set* regs) const
 {
     GenesysRegister *r = sanei_genesys_get_address(regs, 0x04);
@@ -128,11 +110,6 @@ bool CommandSetGl646::test_buffer_empty_bit(SANE_Byte val) const
     return (val & REG41_BUFEMPTY);
 }
 
-bool CommandSetGl646::test_motor_flag_bit(SANE_Byte val) const
-{
-    return (val & REG41_MOTMFLG);
-}
-
 /**
  * decodes and prints content of status (0x41) register
  * @param val value read from reg41
@@ -1227,10 +1204,9 @@ void CommandSetGl646::set_powersaving(Genesys_Device* dev, int delay /* in minut
     local_reg.find_reg(0x03).value = (local_reg.get8(0x03) & 0xf0) | 0x0f;	/* enable lampdog and set lamptime = 7 */
 
   time = delay * 1000 * 60;	/* -> msec */
-  exposure_time =
-    (uint32_t) (time * 32000.0 /
+    exposure_time = static_cast<std::uint32_t>((time * 32000.0 /
                 (24.0 * 64.0 * (local_reg.get8(0x03) & REG03_LAMPTIM) *
-		 1024.0) + 0.5);
+         1024.0) + 0.5));
   /* 32000 = system clock, 24 = clocks per pixel */
   rate = (exposure_time + 65536) / 65536;
   if (rate > 4)
@@ -1415,8 +1391,8 @@ void CommandSetGl646::detect_document_end(Genesys_Device* dev) const
        * total_bytes_read is the number of bytes sent to frontend
        * read_bytes_left is the number of bytes to read from the scanner
        */
-      DBG(DBG_io, "%s: total_bytes_to_read=%lu\n", __func__, (u_long) dev->total_bytes_to_read);
-      DBG(DBG_io, "%s: total_bytes_read   =%lu\n", __func__, (u_long) dev->total_bytes_read);
+      DBG(DBG_io, "%s: total_bytes_to_read=%zu\n", __func__, dev->total_bytes_to_read);
+      DBG(DBG_io, "%s: total_bytes_read   =%zu\n", __func__, dev->total_bytes_read);
 
         // amount of data available from scanner is what to scan
         sanei_genesys_read_valid_words(dev, &bytes_left);
@@ -1435,8 +1411,8 @@ void CommandSetGl646::detect_document_end(Genesys_Device* dev) const
             dev->get_pipeline_source().set_remaining_bytes(bytes_left);
             dev->total_bytes_to_read = dev->total_bytes_read + bytes_left;
         }
-      DBG(DBG_io, "%s: total_bytes_to_read=%lu\n", __func__, (u_long) dev->total_bytes_to_read);
-      DBG(DBG_io, "%s: total_bytes_read   =%lu\n", __func__, (u_long) dev->total_bytes_read);
+      DBG(DBG_io, "%s: total_bytes_to_read=%zu\n", __func__, dev->total_bytes_to_read);
+      DBG(DBG_io, "%s: total_bytes_read   =%zu\n", __func__, dev->total_bytes_read);
     }
 }
 
@@ -2386,7 +2362,7 @@ static void ad_fe_offset_calibration(Genesys_Device* dev, const Genesys_Sensor&
       if (DBG_LEVEL >= DBG_data)
 	{
           char title[30];
-          snprintf(title, 30, "gl646_offset%03d.pnm", (int)bottom);
+          std::snprintf(title, 30, "gl646_offset%03d.pnm", static_cast<int>(bottom));
           sanei_genesys_write_pnm_file (title, line.data(), 8, channels,
 					settings.pixels, settings.lines);
 	}
@@ -2624,7 +2600,7 @@ static void ad_fe_coarse_gain_calibration(Genesys_Device* dev, const Genesys_Sen
       /* log scanning data */
       if (DBG_LEVEL >= DBG_data)
 	{
-          sprintf (title, "gl646_alternative_gain%02d.pnm", (int)pass);
+          sprintf (title, "gl646_alternative_gain%02d.pnm", pass);
           sanei_genesys_write_pnm_file(title, line.data(), 8, channels, settings.pixels,
                                        settings.lines);
 	}
@@ -2757,7 +2733,7 @@ void CommandSetGl646::coarse_gain_calibration(Genesys_Device* dev, const Genesys
       /* log scanning data */
       if (DBG_LEVEL >= DBG_data)
 	{
-          sprintf (title, "gl646_gain%02d.pnm", (int)pass);
+          std::sprintf(title, "gl646_gain%02d.pnm", pass);
           sanei_genesys_write_pnm_file(title, line.data(), 8, channels, settings.pixels,
                                        settings.lines);
 	}
@@ -3444,8 +3420,8 @@ static void write_control(Genesys_Device* dev, const Genesys_Sensor& sensor, int
     {
         case MotorId::XP200:
       /* we put scan's dpi, not motor one */
-      control[0] = LOBYTE (resolution);
-      control[1] = HIBYTE (resolution);
+            control[0] = resolution & 0xff;
+            control[1] = (resolution >> 8) & 0xff;
       control[2] = dev->control[4];
       control[3] = dev->control[5];
       break;
@@ -3503,7 +3479,8 @@ bool CommandSetGl646::is_compatible_calibration(Genesys_Device* dev, const Genes
    * requested scan. In the case of CIS scanners, dpi isn't a criteria */
     if (!dev->model->is_cis) {
         compatible = (dev->session.params.channels == cache->params.channels) &&
-                      (((int) dev->current_setup.xres) == ((int) cache->used_setup.xres));
+                     (static_cast<int>(dev->current_setup.xres) ==
+                          static_cast<int>(cache->used_setup.xres));
     } else {
         compatible = dev->session.params.channels == cache->params.channels;
     }
@@ -3592,8 +3569,7 @@ void CommandSetGl646::search_strip(Genesys_Device* dev, const Genesys_Sensor& se
 
       if (DBG_LEVEL >= DBG_data)
 	{
-          sprintf (title, "gl646_search_strip_%s%02d.pnm", forward ? "fwd" : "bwd",
-		   (int)pass);
+            std::sprintf(title, "gl646_search_strip_%s%02d.pnm", forward ? "fwd" : "bwd", pass);
           sanei_genesys_write_pnm_file (title, data.data(), settings.depth, 1,
 					settings.pixels, settings.lines);
 	}
diff --git a/backend/genesys/gl646.h b/backend/genesys/gl646.h
index 3ef654ea8..cd6e1a2c7 100644
--- a/backend/genesys/gl646.h
+++ b/backend/genesys/gl646.h
@@ -252,14 +252,10 @@ public:
 
     void init_regs_for_scan(Genesys_Device* dev, const Genesys_Sensor& sensor) const override;
 
-    bool get_filter_bit(Genesys_Register_Set * reg) const override;
-    bool get_lineart_bit(Genesys_Register_Set * reg) const override;
     bool get_bitset_bit(Genesys_Register_Set * reg) const override;
     bool get_gain4_bit(Genesys_Register_Set * reg) const override;
-    bool get_fast_feed_bit(Genesys_Register_Set * reg) const override;
 
     bool test_buffer_empty_bit(std::uint8_t val) const override;
-    bool test_motor_flag_bit(std::uint8_t val) const override;
 
     void set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, uint8_t set) const override;
     void set_powersaving(Genesys_Device* dev, int delay) const override;
diff --git a/backend/genesys/gl841.cpp b/backend/genesys/gl841.cpp
index c510033cb..0d177eb96 100644
--- a/backend/genesys/gl841.cpp
+++ b/backend/genesys/gl841.cpp
@@ -57,14 +57,6 @@
 
 #include <vector>
 
-/****************************************************************************
- Low level function
- ****************************************************************************/
-
-/* ------------------------------------------------------------------------ */
-/*                  Read and write RAM, registers and AFE                   */
-/* ------------------------------------------------------------------------ */
-
 // Set address for writing data
 static void gl841_set_buffer_address_gamma(Genesys_Device* dev, uint32_t addr)
 {
@@ -78,28 +70,6 @@ static void gl841_set_buffer_address_gamma(Genesys_Device* dev, uint32_t addr)
     dev->write_register(0x5b, (addr & 0xff));
 }
 
-/****************************************************************************
- Mid level functions
- ****************************************************************************/
-
-bool CommandSetGl841::get_fast_feed_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, 0x02);
-    return (r && (r->value & REG02_FASTFED));
-}
-
-bool CommandSetGl841::get_filter_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, 0x04);
-    return (r && (r->value & REG04_FILTER));
-}
-
-bool CommandSetGl841::get_lineart_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, 0x04);
-    return (r && (r->value & REG04_LINEART));
-}
-
 bool CommandSetGl841::get_bitset_bit(Genesys_Register_Set* regs) const
 {
     GenesysRegister *r = sanei_genesys_get_address(regs, 0x04);
@@ -117,11 +87,6 @@ bool CommandSetGl841::test_buffer_empty_bit(SANE_Byte val) const
     return (val & REG41_BUFEMPTY);
 }
 
-bool CommandSetGl841::test_motor_flag_bit(SANE_Byte val) const
-{
-    return (val & REG41_MOTORENB);
-}
-
 /** copy sensor specific settings */
 /* *dev  : device infos
    *regs : registers to be set
@@ -1825,7 +1790,7 @@ dummy \ scanned lines
     dev->total_bytes_read = 0;
     dev->total_bytes_to_read = session.output_line_bytes_requested * session.params.lines;
 
-  DBG(DBG_info, "%s: total bytes to send = %lu\n", __func__, (u_long) dev->total_bytes_to_read);
+    DBG(DBG_info, "%s: total bytes to send = %zu\n", __func__, dev->total_bytes_to_read);
 }
 
 void CommandSetGl841::calculate_current_setup(Genesys_Device * dev,
@@ -2045,8 +2010,7 @@ void CommandSetGl841::set_powersaving(Genesys_Device* dev, int delay /* in minut
     }
 
   time = delay * 1000 * 60;	/* -> msec */
-  exposure_time =
-    (uint32_t) (time * 32000.0 /
+  exposure_time = static_cast<std::uint32_t>(time * 32000.0 /
                  (24.0 * 64.0 * (local_reg.find_reg(0x03).value & REG03_LAMPTIM) *
 		  1024.0) + 0.5);
   /* 32000 = system clock, 24 = clocks per pixel */
@@ -2678,7 +2642,7 @@ void CommandSetGl841::init_regs_for_coarse_calibration(Genesys_Device* dev,
 void CommandSetGl841::init_regs_for_shading(Genesys_Device* dev, const Genesys_Sensor& sensor,
                                             Genesys_Register_Set& regs) const
 {
-    DBG_HELPER_ARGS(dbg, "lines = %d", (int)(dev->calib_lines));
+    DBG_HELPER_ARGS(dbg, "lines = %zu", dev->calib_lines);
   SANE_Int ydpi;
   float starty=0;
 
@@ -3725,7 +3689,7 @@ void CommandSetGl841::init_regs_for_warmup(Genesys_Device* dev, const Genesys_Se
                                            int* total_size) const
 {
     DBG_HELPER(dbg);
-  int num_pixels = (int) (4 * 300);
+    int num_pixels = 4 * 300;
   *local_reg = dev->reg;
 
 /* okay.. these should be defaults stored somewhere */
@@ -4210,7 +4174,7 @@ void CommandSetGl841::send_shading_data(Genesys_Device* dev, const Genesys_Senso
     }
 
   /* data is whole line, we extract only the part for the scanned area */
-  length = (uint32_t) (size / 3);
+    length = static_cast<std::uint32_t>(size / 3);
     unsigned strpixel = dev->session.pixel_startx;
     unsigned endpixel = dev->session.pixel_endx;
 
@@ -4225,7 +4189,7 @@ void CommandSetGl841::send_shading_data(Genesys_Device* dev, const Genesys_Senso
   /* binary data logging */
   if(DBG_LEVEL>=DBG_data)
     {
-      dev->binary=fopen("binary.pnm","wb");
+        dev->binary = std::fopen("binary.pnm","wb");
         lines = dev->reg.get24(REG_LINCNT);
         channels = dev->session.params.channels;
         if (dev->binary != nullptr) {
diff --git a/backend/genesys/gl841.h b/backend/genesys/gl841.h
index fa7a414e1..6c20b78f8 100644
--- a/backend/genesys/gl841.h
+++ b/backend/genesys/gl841.h
@@ -81,14 +81,10 @@ public:
 
     void init_regs_for_scan(Genesys_Device* dev, const Genesys_Sensor& sensor) const override;
 
-    bool get_filter_bit(Genesys_Register_Set* reg) const override;
-    bool get_lineart_bit(Genesys_Register_Set* reg) const override;
     bool get_bitset_bit(Genesys_Register_Set* reg) const override;
     bool get_gain4_bit(Genesys_Register_Set* reg) const override;
-    bool get_fast_feed_bit(Genesys_Register_Set* reg) const override;
 
     bool test_buffer_empty_bit(std::uint8_t val) const override;
-    bool test_motor_flag_bit(std::uint8_t val) const override;
 
     void set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, uint8_t set) const override;
     void set_powersaving(Genesys_Device* dev, int delay) const override;
diff --git a/backend/genesys/gl843.cpp b/backend/genesys/gl843.cpp
index 58adb399d..3551a1d41 100644
--- a/backend/genesys/gl843.cpp
+++ b/backend/genesys/gl843.cpp
@@ -50,14 +50,6 @@
 #include <string>
 #include <vector>
 
-/****************************************************************************
- Low level function
- ****************************************************************************/
-
-/* ------------------------------------------------------------------------ */
-/*                  Read and write RAM, registers and AFE                   */
-/* ------------------------------------------------------------------------ */
-
 // Set address for writing data
 static void gl843_set_buffer_address(Genesys_Device* dev, uint32_t addr)
 {
@@ -96,28 +88,6 @@ static void write_data(Genesys_Device* dev, uint32_t addr, uint32_t size, uint8_
     gl843_set_buffer_address(dev, 0);
 }
 
-/****************************************************************************
- Mid level functions
- ****************************************************************************/
-
-bool CommandSetGl843::get_fast_feed_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address (regs, REG02);
-    return (r && (r->value & REG02_FASTFED));
-}
-
-bool CommandSetGl843::get_filter_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address (regs, REG04);
-    return (r && (r->value & REG04_FILTER));
-}
-
-bool CommandSetGl843::get_lineart_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address (regs, REG04);
-    return (r && (r->value & REG04_LINEART));
-}
-
 bool CommandSetGl843::get_bitset_bit(Genesys_Register_Set* regs) const
 {
     GenesysRegister *r = sanei_genesys_get_address (regs, REG04);
@@ -161,11 +131,6 @@ bool CommandSetGl843::test_buffer_empty_bit(SANE_Byte val) const
     return (val & REG41_BUFEMPTY);
 }
 
-bool CommandSetGl843::test_motor_flag_bit(SANE_Byte val) const
-{
-    return (val & REG41_MOTORENB);
-}
-
 /** copy sensor specific settings */
 static void gl843_setup_sensor(Genesys_Device* dev, const Genesys_Sensor& sensor,
                                Genesys_Register_Set* regs)
@@ -1356,7 +1321,7 @@ static void gl843_init_scan_regs(Genesys_Device* dev, const Genesys_Sensor& sens
   dev->total_bytes_read = 0;
     dev->total_bytes_to_read = session.output_line_bytes_requested * session.params.lines;
 
-  DBG(DBG_info, "%s: total bytes to send = %lu\n", __func__, (u_long) dev->total_bytes_to_read);
+    DBG(DBG_info, "%s: total bytes to send = %zu\n", __func__, dev->total_bytes_to_read);
 }
 
 void CommandSetGl843::calculate_current_setup(Genesys_Device * dev,
@@ -2864,7 +2829,8 @@ void CommandSetGl843::offset_calibration(Genesys_Device* dev, const Genesys_Sens
   if (DBG_LEVEL >= DBG_data)
     {
       sanei_genesys_write_file("gl843_offset_all_desc.txt",
-                               (uint8_t*) debug_image_info.data(), debug_image_info.size());
+                               reinterpret_cast<const std::uint8_t*>(debug_image_info.data()),
+                               debug_image_info.size());
       sanei_genesys_write_pnm_file("gl843_offset_all.pnm",
                                    debug_image.data(), bpp, channels, pixels, debug_image_lines);
     }
@@ -2997,7 +2963,7 @@ void CommandSetGl843::coarse_gain_calibration(Genesys_Device* dev, const Genesys
       dev->frontend.set_gain(ch, code);
 
         DBG(DBG_proc, "%s: channel %d, max=%d, target=%d, setting:%d\n", __func__, ch, curr_output,
-            (int) target_value, code);
+            static_cast<int>(target_value), code);
     }
 
     if (dev->model->is_cis) {
@@ -3334,7 +3300,7 @@ void CommandSetGl843::search_strip(Genesys_Device* dev, const Genesys_Sensor& se
     {
       char fn[40];
       snprintf(fn, 40, "gl843_search_strip_%s_%s%02d.pnm",
-               black ? "black" : "white", forward ? "fwd" : "bwd", (int)pass);
+               black ? "black" : "white", forward ? "fwd" : "bwd", pass);
         sanei_genesys_write_pnm_file(fn, data);
     }
 
@@ -3357,8 +3323,8 @@ void CommandSetGl843::search_strip(Genesys_Device* dev, const Genesys_Sensor& se
       if (DBG_LEVEL >= DBG_data)
 	{
           char fn[40];
-          snprintf(fn, 40, "gl843_search_strip_%s_%s%02d.pnm",
-                   black ? "black" : "white", forward ? "fwd" : "bwd", (int)pass);
+            std::snprintf(fn, 40, "gl843_search_strip_%s_%s%02d.pnm",
+                          black ? "black" : "white", forward ? "fwd" : "bwd", pass);
             sanei_genesys_write_pnm_file(fn, data);
 	}
 
diff --git a/backend/genesys/gl843.h b/backend/genesys/gl843.h
index e890ce947..26c388cda 100644
--- a/backend/genesys/gl843.h
+++ b/backend/genesys/gl843.h
@@ -84,14 +84,10 @@ public:
 
     void init_regs_for_scan(Genesys_Device* dev, const Genesys_Sensor& sensor) const override;
 
-    bool get_filter_bit(Genesys_Register_Set * reg) const override;
-    bool get_lineart_bit(Genesys_Register_Set * reg) const override;
     bool get_bitset_bit(Genesys_Register_Set * reg) const override;
     bool get_gain4_bit(Genesys_Register_Set * reg) const override;
-    bool get_fast_feed_bit(Genesys_Register_Set * reg) const override;
 
     bool test_buffer_empty_bit(std::uint8_t val) const override;
-    bool test_motor_flag_bit(std::uint8_t val) const override;
 
     void set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, uint8_t set) const override;
     void set_powersaving(Genesys_Device* dev, int delay) const override;
diff --git a/backend/genesys/gl846.cpp b/backend/genesys/gl846.cpp
index 9056529df..ced5ef76b 100644
--- a/backend/genesys/gl846.cpp
+++ b/backend/genesys/gl846.cpp
@@ -54,28 +54,6 @@
 
 #include <vector>
 
-/****************************************************************************
- Mid level functions
- ****************************************************************************/
-
-bool CommandSetGl846::get_fast_feed_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, REG02);
-    return (r && (r->value & REG02_FASTFED));
-}
-
-bool CommandSetGl846::get_filter_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, REG04);
-    return (r && (r->value & REG04_FILTER));
-}
-
-bool CommandSetGl846::get_lineart_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, REG04);
-    return (r && (r->value & REG04_LINEART));
-}
-
 bool CommandSetGl846::get_bitset_bit(Genesys_Register_Set* regs) const
 {
     GenesysRegister *r = sanei_genesys_get_address(regs, REG04);
@@ -93,11 +71,6 @@ bool CommandSetGl846::test_buffer_empty_bit(SANE_Byte val) const
     return (val & REG41_BUFEMPTY);
 }
 
-bool CommandSetGl846::test_motor_flag_bit(SANE_Byte val) const
-{
-    return (val & REG41_MOTORENB);
-}
-
 /**
  * compute the step multiplier used
  */
@@ -879,7 +852,7 @@ static void gl846_init_scan_regs(Genesys_Device* dev, const Genesys_Sensor& sens
     dev->total_bytes_read = 0;
     dev->total_bytes_to_read = session.output_line_bytes_requested * session.params.lines;
 
-  DBG(DBG_info, "%s: total bytes to send = %lu\n", __func__, (u_long) dev->total_bytes_to_read);
+    DBG(DBG_info, "%s: total bytes to send = %zu\n", __func__, dev->total_bytes_to_read);
 }
 
 void CommandSetGl846::calculate_current_setup(Genesys_Device* dev,
@@ -1391,8 +1364,8 @@ void CommandSetGl846::init_regs_for_shading(Genesys_Device* dev, const Genesys_S
   if(dev->calib_resolution==4800)
     dev->calib_lines *= 2;
   dev->calib_pixels = (sensor.sensor_pixels*dev->calib_resolution)/sensor.optical_res;
-  DBG(DBG_io, "%s: calib_lines  = %d\n", __func__, (unsigned int)dev->calib_lines);
-  DBG(DBG_io, "%s: calib_pixels = %d\n", __func__, (unsigned int)dev->calib_pixels);
+    DBG(DBG_io, "%s: calib_lines  = %zu\n", __func__, dev->calib_lines);
+    DBG(DBG_io, "%s: calib_pixels = %zu\n", __func__, dev->calib_pixels);
 
   /* this is aworkaround insufficent distance for slope
    * motor acceleration TODO special motor slope for shading  */
@@ -1537,7 +1510,7 @@ void CommandSetGl846::send_shading_data(Genesys_Device* dev, const Genesys_Senso
      write(0x1003e000,0x00000dd8)
      write(0x10068000,0x00000dd8)
    */
-  length = (uint32_t) (size / 3);
+    length = static_cast<uint32_t>(size / 3);
     unsigned strpixel = dev->session.pixel_startx;
     unsigned endpixel = dev->session.pixel_endx;
 
@@ -1549,7 +1522,7 @@ void CommandSetGl846::send_shading_data(Genesys_Device* dev, const Genesys_Senso
 
   if(DBG_LEVEL>=DBG_data)
     {
-      dev->binary=fopen("binary.pnm","wb");
+        dev->binary = std::fopen("binary.pnm", "wb");
         lines = dev->reg.get24(REG_LINCNT);
         unsigned channels = dev->session.params.channels;
         if (dev->binary != nullptr) {
@@ -2008,8 +1981,8 @@ void CommandSetGl846::search_strip(Genesys_Device* dev, const Genesys_Sensor& se
   pass = 0;
   if (DBG_LEVEL >= DBG_data)
     {
-      sprintf(title, "gl846_search_strip_%s_%s%02d.pnm",
-              black ? "black" : "white", forward ? "fwd" : "bwd", (int)pass);
+        std::sprintf(title, "gl846_search_strip_%s_%s%02d.pnm",
+                     black ? "black" : "white", forward ? "fwd" : "bwd", pass);
       sanei_genesys_write_pnm_file(title, data.data(), depth, channels, pixels, lines);
     }
 
@@ -2031,8 +2004,8 @@ void CommandSetGl846::search_strip(Genesys_Device* dev, const Genesys_Sensor& se
 
       if (DBG_LEVEL >= DBG_data)
         {
-          sprintf(title, "gl846_search_strip_%s_%s%02d.pnm",
-                  black ? "black" : "white", forward ? "fwd" : "bwd", (int)pass);
+            std::sprintf(title, "gl846_search_strip_%s_%s%02d.pnm",
+                         black ? "black" : "white", forward ? "fwd" : "bwd", pass);
           sanei_genesys_write_pnm_file(title, data.data(), depth, channels, pixels, lines);
         }
 
@@ -2391,7 +2364,7 @@ void CommandSetGl846::coarse_gain_calibration(Genesys_Device* dev, const Genesys
         }
       max[j] = max[j] / (pixels/2);
 
-      gain[j] = ((float) sensor.gain_white_ref*coeff) / max[j];
+        gain[j] = (static_cast<float>(sensor.gain_white_ref) * coeff) / max[j];
 
       /* turn logical gain value into gain code, checking for overflow */
       code = 283 - 208 / gain[j];
diff --git a/backend/genesys/gl846.h b/backend/genesys/gl846.h
index 19c4ef26b..155a9a0d5 100644
--- a/backend/genesys/gl846.h
+++ b/backend/genesys/gl846.h
@@ -153,14 +153,10 @@ public:
 
     void init_regs_for_scan(Genesys_Device* dev, const Genesys_Sensor& sensor) const override;
 
-    bool get_filter_bit(Genesys_Register_Set * reg) const override;
-    bool get_lineart_bit(Genesys_Register_Set * reg) const override;
     bool get_bitset_bit(Genesys_Register_Set * reg) const override;
     bool get_gain4_bit(Genesys_Register_Set * reg) const override;
-    bool get_fast_feed_bit(Genesys_Register_Set * reg) const override;
 
     bool test_buffer_empty_bit(std::uint8_t val) const override;
-    bool test_motor_flag_bit(std::uint8_t val) const override;
 
     void set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, uint8_t set) const override;
     void set_powersaving(Genesys_Device* dev, int delay) const override;
diff --git a/backend/genesys/gl847.cpp b/backend/genesys/gl847.cpp
index b6afc820e..48e303d2e 100644
--- a/backend/genesys/gl847.cpp
+++ b/backend/genesys/gl847.cpp
@@ -49,28 +49,6 @@
 
 #include <vector>
 
-/****************************************************************************
- Mid level functions
- ****************************************************************************/
-
-bool CommandSetGl847::get_fast_feed_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, REG02);
-    return (r && (r->value & REG02_FASTFED));
-}
-
-bool CommandSetGl847::get_filter_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, REG04);
-    return (r && (r->value & REG04_FILTER));
-}
-
-bool CommandSetGl847::get_lineart_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, REG04);
-    return (r && (r->value & REG04_LINEART));
-}
-
 bool CommandSetGl847::get_bitset_bit(Genesys_Register_Set* regs) const
 {
     GenesysRegister *r = sanei_genesys_get_address(regs, REG04);
@@ -88,11 +66,6 @@ bool CommandSetGl847::test_buffer_empty_bit(SANE_Byte val) const
     return (val & REG41_BUFEMPTY);
 }
 
-bool CommandSetGl847::test_motor_flag_bit(SANE_Byte val) const
-{
-    return (val & REG41_MOTORENB);
-}
-
 /**
  * compute the step multiplier used
  */
@@ -881,8 +854,7 @@ static void gl847_init_scan_regs(Genesys_Device* dev, const Genesys_Sensor& sens
     dev->total_bytes_read = 0;
     dev->total_bytes_to_read = session.output_line_bytes_requested * session.params.lines;
 
-  DBG(DBG_info, "%s: total bytes to send = %lu\n", __func__, (u_long) dev->total_bytes_to_read);
-/* END TODO */
+    DBG(DBG_info, "%s: total bytes to send = %zu\n", __func__, dev->total_bytes_to_read);
 }
 
 void CommandSetGl847::calculate_current_setup(Genesys_Device * dev,
@@ -1432,8 +1404,8 @@ void CommandSetGl847::init_regs_for_shading(Genesys_Device* dev, const Genesys_S
   if(dev->calib_resolution==4800)
     dev->calib_lines *= 2;
   dev->calib_pixels = (sensor.sensor_pixels*dev->calib_resolution)/sensor.optical_res;
-  DBG(DBG_io, "%s: calib_lines  = %d\n", __func__, (int)dev->calib_lines);
-  DBG(DBG_io, "%s: calib_pixels = %d\n", __func__, (int)dev->calib_pixels);
+    DBG(DBG_io, "%s: calib_lines  = %zu\n", __func__, dev->calib_lines);
+    DBG(DBG_io, "%s: calib_pixels = %zu\n", __func__, dev->calib_pixels);
 
   /* this is aworkaround insufficent distance for slope
    * motor acceleration TODO special motor slope for shading  */
@@ -1577,7 +1549,7 @@ void CommandSetGl847::send_shading_data(Genesys_Device* dev, const Genesys_Senso
      write(0x1003e000,0x00000dd8)
      write(0x10068000,0x00000dd8)
    */
-  length = (uint32_t) (size / 3);
+    length = static_cast<std::uint32_t>(size / 3);
     std::uint32_t strpixel = dev->session.pixel_startx;
     std::uint32_t endpixel = dev->session.pixel_endx;
 
@@ -1589,7 +1561,7 @@ void CommandSetGl847::send_shading_data(Genesys_Device* dev, const Genesys_Senso
 
   if(DBG_LEVEL>=DBG_data)
     {
-      dev->binary=fopen("binary.pnm","wb");
+        dev->binary = std::fopen("binary.pnm", "wb");
         lines = dev->reg.get24(REG_LINCNT);
         unsigned channels = dev->session.params.channels;
         if (dev->binary != nullptr) {
@@ -2084,8 +2056,8 @@ void CommandSetGl847::search_strip(Genesys_Device* dev, const Genesys_Sensor& se
   pass = 0;
   if (DBG_LEVEL >= DBG_data)
     {
-      sprintf(title, "gl847_search_strip_%s_%s%02d.pnm",
-              black ? "black" : "white", forward ? "fwd" : "bwd", (int)pass);
+        std::sprintf(title, "gl847_search_strip_%s_%s%02d.pnm",
+                     black ? "black" : "white", forward ? "fwd" : "bwd", pass);
       sanei_genesys_write_pnm_file(title, data.data(), depth, channels, pixels, lines);
     }
 
@@ -2479,7 +2451,7 @@ void CommandSetGl847::coarse_gain_calibration(Genesys_Device* dev, const Genesys
 	}
       max[j] = max[j] / (pixels/2);
 
-      gain[j] = ((float) sensor.gain_white_ref*coeff) / max[j];
+      gain[j] = (static_cast<float>(sensor.gain_white_ref) * coeff) / max[j];
 
       /* turn logical gain value into gain code, checking for overflow */
       code = 283 - 208 / gain[j];
diff --git a/backend/genesys/gl847.h b/backend/genesys/gl847.h
index f9a5dd671..d584bbe60 100644
--- a/backend/genesys/gl847.h
+++ b/backend/genesys/gl847.h
@@ -137,14 +137,10 @@ public:
 
     void init_regs_for_scan(Genesys_Device* dev, const Genesys_Sensor& sensor) const override;
 
-    bool get_filter_bit(Genesys_Register_Set * reg) const override;
-    bool get_lineart_bit(Genesys_Register_Set * reg) const override;
     bool get_bitset_bit(Genesys_Register_Set * reg) const override;
     bool get_gain4_bit(Genesys_Register_Set * reg) const override;
-    bool get_fast_feed_bit(Genesys_Register_Set * reg) const override;
 
     bool test_buffer_empty_bit(std::uint8_t val) const override;
-    bool test_motor_flag_bit(std::uint8_t val) const override;
 
     void set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, uint8_t set) const override;
     void set_powersaving(Genesys_Device* dev, int delay) const override;
diff --git a/backend/genesys/image_pipeline.h b/backend/genesys/image_pipeline.h
index cdc081509..44a8aa796 100644
--- a/backend/genesys/image_pipeline.h
+++ b/backend/genesys/image_pipeline.h
@@ -450,7 +450,7 @@ private:
     std::size_t height_ = 0;
 
     std::size_t current_line_ = 0;
-    std::vector<uint8_t> cached_line_;
+    std::vector<std::uint8_t> cached_line_;
 };
 
 // A pipeline node that scales rows to the specified width by using a point filter
@@ -471,7 +471,7 @@ private:
     ImagePipelineNode& source_;
     std::size_t width_ = 0;
 
-    std::vector<uint8_t> cached_line_;
+    std::vector<std::uint8_t> cached_line_;
 };
 
 // A pipeline node that mimics the calibration behavior on Genesys chips
diff --git a/backend/genesys/image_pixel.cpp b/backend/genesys/image_pixel.cpp
index 31673b21f..5787a7e38 100644
--- a/backend/genesys/image_pixel.cpp
+++ b/backend/genesys/image_pixel.cpp
@@ -205,7 +205,7 @@ void set_pixel_to_row(std::uint8_t* data, std::size_t x, Pixel pixel, PixelForma
             float val = (pixel.r >> 8) * 0.3f;
             val += (pixel.g >> 8) * 0.59;
             val += (pixel.b >> 8) * 0.11;
-            data[x] = static_cast<uint16_t>(val);
+            data[x] = static_cast<std::uint16_t>(val);
             return;
         }
         case PixelFormat::I16: {
diff --git a/backend/genesys/low.cpp b/backend/genesys/low.cpp
index 0ea9ae951..3b39ec130 100644
--- a/backend/genesys/low.cpp
+++ b/backend/genesys/low.cpp
@@ -84,7 +84,7 @@ void sanei_genesys_init_cmd_set(Genesys_Device* dev)
 /*                  General IO and debugging functions                      */
 /* ------------------------------------------------------------------------ */
 
-void sanei_genesys_write_file(const char* filename, uint8_t* data, size_t length)
+void sanei_genesys_write_file(const char* filename, const std::uint8_t* data, size_t length)
 {
     DBG_HELPER(dbg);
     FILE *out;
@@ -286,9 +286,9 @@ void sanei_genesys_bulk_read_data(Genesys_Device * dev, uint8_t addr, uint8_t* d
     }
 
     if (is_addr_used) {
-        DBG(DBG_io, "%s: requesting %lu bytes from 0x%02x addr\n", __func__, (u_long) len, addr);
+        DBG(DBG_io, "%s: requesting %zu bytes from 0x%02x addr\n", __func__, len, addr);
     } else {
-        DBG(DBG_io, "%s: requesting %lu bytes\n", __func__, (u_long) len);
+        DBG(DBG_io, "%s: requesting %zu bytes\n", __func__, len);
     }
 
     if (len == 0)
@@ -320,12 +320,11 @@ void sanei_genesys_bulk_read_data(Genesys_Device * dev, uint8_t addr, uint8_t* d
             sanei_genesys_bulk_read_data_send_header(dev, size);
         }
 
-        DBG(DBG_io2, "%s: trying to read %lu bytes of data\n", __func__, (u_long) size);
+        DBG(DBG_io2, "%s: trying to read %zu bytes of data\n", __func__, size);
 
         dev->usb_dev.bulk_read(data, &size);
 
-        DBG(DBG_io2, "%s: read %lu bytes, %lu remaining\n", __func__,
-            (u_long) size, (u_long) (target - size));
+        DBG(DBG_io2, "%s: read %zu bytes, %zu remaining\n", __func__, size, target - size);
 
         target -= size;
         data += size;
@@ -338,7 +337,7 @@ void sanei_genesys_bulk_read_data(Genesys_Device * dev, uint8_t addr, uint8_t* d
 
 void sanei_genesys_bulk_write_data(Genesys_Device* dev, uint8_t addr, uint8_t* data, size_t len)
 {
-    DBG_HELPER_ARGS(dbg, "writing %lu bytes", (u_long) len);
+    DBG_HELPER_ARGS(dbg, "writing %zu bytes", len);
 
     // supported: GL646, GL841, GL843
     size_t size;
@@ -379,8 +378,7 @@ void sanei_genesys_bulk_write_data(Genesys_Device* dev, uint8_t addr, uint8_t* d
 
         dev->usb_dev.bulk_write(data, &size);
 
-        DBG(DBG_io2, "%s: wrote %lu bytes, %lu remaining\n", __func__, (u_long) size,
-            (u_long) (len - size));
+        DBG(DBG_io2, "%s: wrote %zu bytes, %zu remaining\n", __func__, size, len - size);
 
         len -= size;
         data += size;
@@ -550,7 +548,7 @@ void sanei_genesys_read_register(Genesys_Device* dev, uint16_t reg, uint8_t* val
     }
 
   /* 8 bit register address space */
-    reg8=(SANE_Byte)(reg& 0Xff);
+    reg8 = reg & 0Xff;
 
     dev->usb_dev.control_msg(REQUEST_TYPE_OUT, REQUEST_REGISTER, VALUE_SET_REGISTER, INDEX,
                              1, &reg8);
@@ -831,7 +829,7 @@ void wait_until_has_valid_words(Genesys_Device* dev)
 // Read data (e.g scanned image) from scan buffer
 void sanei_genesys_read_data_from_scanner(Genesys_Device* dev, uint8_t* data, size_t size)
 {
-    DBG_HELPER_ARGS(dbg, "size = %lu bytes", (u_long) size);
+    DBG_HELPER_ARGS(dbg, "size = %zu bytes", size);
 
   if (size & 1)
     DBG(DBG_info, "WARNING %s: odd number of bytes\n", __func__);
@@ -1003,8 +1001,7 @@ void sanei_genesys_bulk_write_register(Genesys_Device* dev, const Genesys_Regist
             buffer.push_back(r.value);
         }
 
-        DBG(DBG_io, "%s (elems= %lu, size = %lu)\n", __func__, (u_long) reg.size(),
-            (u_long) buffer.size());
+        DBG(DBG_io, "%s (elems= %zu, size = %zu)\n", __func__, reg.size(), buffer.size());
 
         if (dev->model->asic_type == AsicType::GL646) {
             outdata[0] = BULK_OUT;
@@ -1040,7 +1037,7 @@ void sanei_genesys_bulk_write_register(Genesys_Device* dev, const Genesys_Regist
         }
     }
 
-    DBG (DBG_io, "%s: wrote %lu registers\n", __func__, (u_long) reg.size());
+    DBG (DBG_io, "%s: wrote %zu registers\n", __func__, reg.size());
 }
 
 
@@ -1142,7 +1139,7 @@ void sanei_genesys_generate_gamma_buffer(Genesys_Device* dev,
   if(dev->settings.contrast!=0 || dev->settings.brightness!=0)
     {
       std::vector<uint16_t> lut(65536);
-      sanei_genesys_load_lut((unsigned char *)lut.data(),
+      sanei_genesys_load_lut(reinterpret_cast<unsigned char *>(lut.data()),
                              bits,
                              bits,
                              0,
@@ -1525,7 +1522,7 @@ void compute_session(Genesys_Device* dev, ScanSession& s, const Genesys_Sensor&
             // for HP3670, stagger happens only at >=1200 dpi
             if ((dev->model->motor_id != MotorId::HP3670 &&
                  dev->model->motor_id != MotorId::HP2400) ||
-                s.params.yres >= (unsigned) sensor.optical_res)
+                s.params.yres >= static_cast<unsigned>(sensor.optical_res))
             {
                 s.num_staggered_lines = (4 * s.params.yres) / dev->motor.base_ydpi;
             }
@@ -2287,7 +2284,7 @@ bool sanei_genesys_is_compatible_calibration(Genesys_Device * dev, const Genesys
   /* a calibration cache is compatible if color mode and x dpi match the user
    * requested scan. In the case of CIS scanners, dpi isn't a criteria */
     if (!dev->model->is_cis) {
-        compatible = (dev->settings.xres == ((int) cache->used_setup.xres));
+        compatible = (dev->settings.xres == static_cast<int>(cache->used_setup.xres));
     }
   else
     {
@@ -2417,7 +2414,7 @@ void sanei_genesys_load_lut(unsigned char* lut,
   int max_in_val = (1 << in_bits) - 1;
   int max_out_val = (1 << out_bits) - 1;
   uint8_t *lut_p8 = lut;
-  uint16_t *lut_p16 = (uint16_t *) lut;
+    uint16_t* lut_p16 = reinterpret_cast<std::uint16_t*>(lut);
 
   /* slope is converted to rise per unit run:
    * first [-127,127] to [-.999,.999]
@@ -2425,16 +2422,16 @@ void sanei_genesys_load_lut(unsigned char* lut,
    * then take the tangent (T.O.A)
    * then multiply by the normal linear slope
    * because the table may not be square, i.e. 1024x256*/
-  rise = tan ((double) slope / 128 * M_PI_4 + M_PI_4) * max_out_val / max_in_val;
+    rise = std::tan(static_cast<double>(slope) / 128 * M_PI_4 + M_PI_4) * max_out_val / max_in_val;
 
   /* line must stay vertically centered, so figure
    * out vertical offset at central input value */
-  shift = (double) max_out_val / 2 - (rise * max_in_val / 2);
+    shift = static_cast<double>(max_out_val) / 2 - (rise * max_in_val / 2);
 
   /* convert the user offset setting to scale of output
    * first [-127,127] to [-1,1]
    * then to [-max_out_val/2,max_out_val/2]*/
-  shift += (double) offset / 127 * max_out_val / 2;
+    shift += static_cast<double>(offset) / 127 * max_out_val / 2;
 
   for (i = 0; i <= max_in_val; i++)
     {
diff --git a/backend/genesys/low.h b/backend/genesys/low.h
index d45928165..20a04c859 100644
--- a/backend/genesys/low.h
+++ b/backend/genesys/low.h
@@ -372,10 +372,6 @@ extern void sanei_genesys_fe_write_data(Genesys_Device* dev, uint8_t addr, uint1
 SANE_Int sanei_genesys_exposure_time2(Genesys_Device * dev, float ydpi, int step_type,
                                       int endpixel, int led_exposure);
 
-extern SANE_Int
-sanei_genesys_exposure_time (Genesys_Device * dev, Genesys_Register_Set * reg,
-			     int xdpi);
-
 SANE_Int sanei_genesys_generate_slope_table(std::vector<uint16_t>& slope_table, unsigned int max_steps,
 			      unsigned int use_steps, uint16_t stop_at,
 			      uint16_t vstart, uint16_t vend,
@@ -408,7 +404,7 @@ extern void sanei_genesys_search_reference_point(Genesys_Device* dev, Genesys_Se
                                                  const uint8_t* src_data, int start_pixel, int dpi,
                                                  int width, int height);
 
-extern void sanei_genesys_write_file(const char* filename, uint8_t* data, size_t length);
+extern void sanei_genesys_write_file(const char* filename, const std::uint8_t* data, size_t length);
 
 extern void sanei_genesys_write_pnm_file(const char* filename, const std::uint8_t* data, int depth,
                                          int channels, int pixels_per_line, int lines);