New upstream version 1.0.29upstream/1.0.29

1 files changed, 2269 insertions, 0 deletions

diff --git a/backend/genesys/gl124.cpp b/backend/genesys/gl124.cpp
new file mode 100644
index 0000000..054f1ef
--- /dev/null
+++ b/backend/genesys/gl124.cpp
@@ -0,0 +1,2269 @@
+/* sane - Scanner Access Now Easy.
+
+   Copyright (C) 2010-2016 Stéphane Voltz <stef.dev@free.fr>
+
+
+   This file is part of the SANE package.
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+   MA 02111-1307, USA.
+
+   As a special exception, the authors of SANE give permission for
+   additional uses of the libraries contained in this release of SANE.
+
+   The exception is that, if you link a SANE library with other files
+   to produce an executable, this does not by itself cause the
+   resulting executable to be covered by the GNU General Public
+   License.  Your use of that executable is in no way restricted on
+   account of linking the SANE library code into it.
+
+   This exception does not, however, invalidate any other reasons why
+   the executable file might be covered by the GNU General Public
+   License.
+
+   If you submit changes to SANE to the maintainers to be included in
+   a subsequent release, you agree by submitting the changes that
+   those changes may be distributed with this exception intact.
+
+   If you write modifications of your own for SANE, it is your choice
+   whether to permit this exception to apply to your modifications.
+   If you do not wish that, delete this exception notice.
+*/
+
+#define DEBUG_DECLARE_ONLY
+
+#include "gl124.h"
+#include "gl124_registers.h"
+#include "test_settings.h"
+
+#include <vector>
+
+namespace genesys {
+namespace gl124 {
+
+/** @brief set all registers to default values .
+ * This function is called only once at the beginning and
+ * fills register startup values for registers reused across scans.
+ * Those that are rarely modified or not modified are written
+ * individually.
+ * @param dev device structure holding register set to initialize
+ */
+static void
+gl124_init_registers (Genesys_Device * dev)
+{
+    DBG_HELPER(dbg);
+
+    dev->reg.clear();
+
+    // default to LiDE 110
+    dev->reg.init_reg(0x01, 0xa2); // + REG_0x01_SHDAREA
+    dev->reg.init_reg(0x02, 0x90);
+    dev->reg.init_reg(0x03, 0x50);
+    dev->reg.init_reg(0x04, 0x03);
+    dev->reg.init_reg(0x05, 0x00);
+
+    if(dev->model->sensor_id == SensorId::CIS_CANON_LIDE_120) {
+    dev->reg.init_reg(0x06, 0x50);
+    dev->reg.init_reg(0x07, 0x00);
+    } else {
+        dev->reg.init_reg(0x03, 0x50 & ~REG_0x03_AVEENB);
+        dev->reg.init_reg(0x06, 0x50 | REG_0x06_GAIN4);
+    }
+    dev->reg.init_reg(0x09, 0x00);
+    dev->reg.init_reg(0x0a, 0xc0);
+    dev->reg.init_reg(0x0b, 0x2a);
+    dev->reg.init_reg(0x0c, 0x12);
+    dev->reg.init_reg(0x11, 0x00);
+    dev->reg.init_reg(0x12, 0x00);
+    dev->reg.init_reg(0x13, 0x0f);
+    dev->reg.init_reg(0x14, 0x00);
+    dev->reg.init_reg(0x15, 0x80);
+    dev->reg.init_reg(0x16, 0x10); // SENSOR_DEF
+    dev->reg.init_reg(0x17, 0x04); // SENSOR_DEF
+    dev->reg.init_reg(0x18, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x19, 0x01); // SENSOR_DEF
+    dev->reg.init_reg(0x1a, 0x30); // SENSOR_DEF
+    dev->reg.init_reg(0x1b, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x1c, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x1d, 0x01); // SENSOR_DEF
+    dev->reg.init_reg(0x1e, 0x10);
+    dev->reg.init_reg(0x1f, 0x00);
+    dev->reg.init_reg(0x20, 0x15); // SENSOR_DEF
+    dev->reg.init_reg(0x21, 0x00);
+    if(dev->model->sensor_id != SensorId::CIS_CANON_LIDE_120) {
+        dev->reg.init_reg(0x22, 0x02);
+    } else {
+        dev->reg.init_reg(0x22, 0x14);
+    }
+    dev->reg.init_reg(0x23, 0x00);
+    dev->reg.init_reg(0x24, 0x00);
+    dev->reg.init_reg(0x25, 0x00);
+    dev->reg.init_reg(0x26, 0x0d);
+    dev->reg.init_reg(0x27, 0x48);
+    dev->reg.init_reg(0x28, 0x00);
+    dev->reg.init_reg(0x29, 0x56);
+    dev->reg.init_reg(0x2a, 0x5e);
+    dev->reg.init_reg(0x2b, 0x02);
+    dev->reg.init_reg(0x2c, 0x02);
+    dev->reg.init_reg(0x2d, 0x58);
+    dev->reg.init_reg(0x3b, 0x00);
+    dev->reg.init_reg(0x3c, 0x00);
+    dev->reg.init_reg(0x3d, 0x00);
+    dev->reg.init_reg(0x3e, 0x00);
+    dev->reg.init_reg(0x3f, 0x02);
+    dev->reg.init_reg(0x40, 0x00);
+    dev->reg.init_reg(0x41, 0x00);
+    dev->reg.init_reg(0x42, 0x00);
+    dev->reg.init_reg(0x43, 0x00);
+    dev->reg.init_reg(0x44, 0x00);
+    dev->reg.init_reg(0x45, 0x00);
+    dev->reg.init_reg(0x46, 0x00);
+    dev->reg.init_reg(0x47, 0x00);
+    dev->reg.init_reg(0x48, 0x00);
+    dev->reg.init_reg(0x49, 0x00);
+    dev->reg.init_reg(0x4f, 0x00);
+    dev->reg.init_reg(0x52, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x53, 0x02); // SENSOR_DEF
+    dev->reg.init_reg(0x54, 0x04); // SENSOR_DEF
+    dev->reg.init_reg(0x55, 0x06); // SENSOR_DEF
+    dev->reg.init_reg(0x56, 0x04); // SENSOR_DEF
+    dev->reg.init_reg(0x57, 0x04); // SENSOR_DEF
+    dev->reg.init_reg(0x58, 0x04); // SENSOR_DEF
+    dev->reg.init_reg(0x59, 0x04); // SENSOR_DEF
+    dev->reg.init_reg(0x5a, 0x1a); // SENSOR_DEF
+    dev->reg.init_reg(0x5b, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x5c, 0xc0); // SENSOR_DEF
+    dev->reg.init_reg(0x5f, 0x00);
+    dev->reg.init_reg(0x60, 0x02);
+    dev->reg.init_reg(0x61, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x62, 0x00);
+    dev->reg.init_reg(0x63, 0x00);
+    dev->reg.init_reg(0x64, 0x00);
+    dev->reg.init_reg(0x65, 0x00);
+    dev->reg.init_reg(0x66, 0x00);
+    dev->reg.init_reg(0x67, 0x00);
+    dev->reg.init_reg(0x68, 0x00);
+    dev->reg.init_reg(0x69, 0x00);
+    dev->reg.init_reg(0x6a, 0x00);
+    dev->reg.init_reg(0x6b, 0x00);
+    dev->reg.init_reg(0x6c, 0x00);
+    dev->reg.init_reg(0x6e, 0x00);
+    dev->reg.init_reg(0x6f, 0x00);
+
+    if (dev->model->sensor_id != SensorId::CIS_CANON_LIDE_120) {
+        dev->reg.init_reg(0x6d, 0xd0);
+        dev->reg.init_reg(0x71, 0x08);
+    } else {
+        dev->reg.init_reg(0x6d, 0x00);
+        dev->reg.init_reg(0x71, 0x1f);
+    }
+    dev->reg.init_reg(0x70, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x71, 0x08); // SENSOR_DEF
+    dev->reg.init_reg(0x72, 0x08); // SENSOR_DEF
+    dev->reg.init_reg(0x73, 0x0a); // SENSOR_DEF
+
+    // CKxMAP
+    dev->reg.init_reg(0x74, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x75, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x76, 0x3c); // SENSOR_DEF
+    dev->reg.init_reg(0x77, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x78, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x79, 0x9f); // SENSOR_DEF
+    dev->reg.init_reg(0x7a, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x7b, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x7c, 0x55); // SENSOR_DEF
+
+    dev->reg.init_reg(0x7d, 0x00);
+    dev->reg.init_reg(0x7e, 0x08);
+    dev->reg.init_reg(0x7f, 0x58);
+
+    if (dev->model->sensor_id != SensorId::CIS_CANON_LIDE_120) {
+        dev->reg.init_reg(0x80, 0x00);
+        dev->reg.init_reg(0x81, 0x14);
+    } else {
+        dev->reg.init_reg(0x80, 0x00);
+        dev->reg.init_reg(0x81, 0x10);
+    }
+
+    // STRPIXEL
+    dev->reg.init_reg(0x82, 0x00);
+    dev->reg.init_reg(0x83, 0x00);
+    dev->reg.init_reg(0x84, 0x00);
+
+    // ENDPIXEL
+    dev->reg.init_reg(0x85, 0x00);
+    dev->reg.init_reg(0x86, 0x00);
+    dev->reg.init_reg(0x87, 0x00);
+
+    dev->reg.init_reg(0x88, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x89, 0x65); // SENSOR_DEF
+    dev->reg.init_reg(0x8a, 0x00);
+    dev->reg.init_reg(0x8b, 0x00);
+    dev->reg.init_reg(0x8c, 0x00);
+    dev->reg.init_reg(0x8d, 0x00);
+    dev->reg.init_reg(0x8e, 0x00);
+    dev->reg.init_reg(0x8f, 0x00);
+    dev->reg.init_reg(0x90, 0x00);
+    dev->reg.init_reg(0x91, 0x00);
+    dev->reg.init_reg(0x92, 0x00);
+    dev->reg.init_reg(0x93, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x94, 0x14); // SENSOR_DEF
+    dev->reg.init_reg(0x95, 0x30); // SENSOR_DEF
+    dev->reg.init_reg(0x96, 0x00); // SENSOR_DEF
+    dev->reg.init_reg(0x97, 0x90); // SENSOR_DEF
+    dev->reg.init_reg(0x98, 0x01); // SENSOR_DEF
+    dev->reg.init_reg(0x99, 0x1f);
+    dev->reg.init_reg(0x9a, 0x00);
+    dev->reg.init_reg(0x9b, 0x80);
+    dev->reg.init_reg(0x9c, 0x80);
+    dev->reg.init_reg(0x9d, 0x3f);
+    dev->reg.init_reg(0x9e, 0x00);
+    dev->reg.init_reg(0x9f, 0x00);
+    dev->reg.init_reg(0xa0, 0x20);
+    dev->reg.init_reg(0xa1, 0x30);
+    dev->reg.init_reg(0xa2, 0x00);
+    dev->reg.init_reg(0xa3, 0x20);
+    dev->reg.init_reg(0xa4, 0x01);
+    dev->reg.init_reg(0xa5, 0x00);
+    dev->reg.init_reg(0xa6, 0x00);
+    dev->reg.init_reg(0xa7, 0x08);
+    dev->reg.init_reg(0xa8, 0x00);
+    dev->reg.init_reg(0xa9, 0x08);
+    dev->reg.init_reg(0xaa, 0x01);
+    dev->reg.init_reg(0xab, 0x00);
+    dev->reg.init_reg(0xac, 0x00);
+    dev->reg.init_reg(0xad, 0x40);
+    dev->reg.init_reg(0xae, 0x01);
+    dev->reg.init_reg(0xaf, 0x00);
+    dev->reg.init_reg(0xb0, 0x00);
+    dev->reg.init_reg(0xb1, 0x40);
+    dev->reg.init_reg(0xb2, 0x00);
+    dev->reg.init_reg(0xb3, 0x09);
+    dev->reg.init_reg(0xb4, 0x5b);
+    dev->reg.init_reg(0xb5, 0x00);
+    dev->reg.init_reg(0xb6, 0x10);
+    dev->reg.init_reg(0xb7, 0x3f);
+    dev->reg.init_reg(0xb8, 0x00);
+    dev->reg.init_reg(0xbb, 0x00);
+    dev->reg.init_reg(0xbc, 0xff);
+    dev->reg.init_reg(0xbd, 0x00);
+    dev->reg.init_reg(0xbe, 0x07);
+    dev->reg.init_reg(0xc3, 0x00);
+    dev->reg.init_reg(0xc4, 0x00);
+
+    /* gamma
+    dev->reg.init_reg(0xc5, 0x00);
+    dev->reg.init_reg(0xc6, 0x00);
+    dev->reg.init_reg(0xc7, 0x00);
+    dev->reg.init_reg(0xc8, 0x00);
+    dev->reg.init_reg(0xc9, 0x00);
+    dev->reg.init_reg(0xca, 0x00);
+    dev->reg.init_reg(0xcb, 0x00);
+    dev->reg.init_reg(0xcc, 0x00);
+    dev->reg.init_reg(0xcd, 0x00);
+    dev->reg.init_reg(0xce, 0x00);
+     */
+
+    if (dev->model->sensor_id == SensorId::CIS_CANON_LIDE_120) {
+        dev->reg.init_reg(0xc5, 0x20);
+        dev->reg.init_reg(0xc6, 0xeb);
+        dev->reg.init_reg(0xc7, 0x20);
+        dev->reg.init_reg(0xc8, 0xeb);
+        dev->reg.init_reg(0xc9, 0x20);
+        dev->reg.init_reg(0xca, 0xeb);
+    }
+
+    // memory layout
+    /*
+    dev->reg.init_reg(0xd0, 0x0a);
+    dev->reg.init_reg(0xd1, 0x1f);
+    dev->reg.init_reg(0xd2, 0x34);
+    */
+    dev->reg.init_reg(0xd3, 0x00);
+    dev->reg.init_reg(0xd4, 0x00);
+    dev->reg.init_reg(0xd5, 0x00);
+    dev->reg.init_reg(0xd6, 0x00);
+    dev->reg.init_reg(0xd7, 0x00);
+    dev->reg.init_reg(0xd8, 0x00);
+    dev->reg.init_reg(0xd9, 0x00);
+
+    // memory layout
+    /*
+    dev->reg.init_reg(0xe0, 0x00);
+    dev->reg.init_reg(0xe1, 0x48);
+    dev->reg.init_reg(0xe2, 0x15);
+    dev->reg.init_reg(0xe3, 0x90);
+    dev->reg.init_reg(0xe4, 0x15);
+    dev->reg.init_reg(0xe5, 0x91);
+    dev->reg.init_reg(0xe6, 0x2a);
+    dev->reg.init_reg(0xe7, 0xd9);
+    dev->reg.init_reg(0xe8, 0x2a);
+    dev->reg.init_reg(0xe9, 0xad);
+    dev->reg.init_reg(0xea, 0x40);
+    dev->reg.init_reg(0xeb, 0x22);
+    dev->reg.init_reg(0xec, 0x40);
+    dev->reg.init_reg(0xed, 0x23);
+    dev->reg.init_reg(0xee, 0x55);
+    dev->reg.init_reg(0xef, 0x6b);
+    dev->reg.init_reg(0xf0, 0x55);
+    dev->reg.init_reg(0xf1, 0x6c);
+    dev->reg.init_reg(0xf2, 0x6a);
+    dev->reg.init_reg(0xf3, 0xb4);
+    dev->reg.init_reg(0xf4, 0x6a);
+    dev->reg.init_reg(0xf5, 0xb5);
+    dev->reg.init_reg(0xf6, 0x7f);
+    dev->reg.init_reg(0xf7, 0xfd);
+    */
+
+    dev->reg.init_reg(0xf8, 0x01);   // other value is 0x05
+    dev->reg.init_reg(0xf9, 0x00);
+    dev->reg.init_reg(0xfa, 0x00);
+    dev->reg.init_reg(0xfb, 0x00);
+    dev->reg.init_reg(0xfc, 0x00);
+    dev->reg.init_reg(0xff, 0x00);
+
+    // fine tune upon device description
+    const auto& sensor = sanei_genesys_find_sensor_any(dev);
+    sanei_genesys_set_dpihw(dev->reg, sensor, sensor.optical_res);
+
+  dev->calib_reg = dev->reg;
+}
+
+/**@brief send slope table for motor movement
+ * Send slope_table in machine byte order
+ * @param dev device to send slope table
+ * @param table_nr index of the slope table in ASIC memory
+ * Must be in the [0-4] range.
+ * @param slope_table pointer to 16 bit values array of the slope table
+ * @param steps number of elemnts in the slope table
+ */
+static void gl124_send_slope_table(Genesys_Device* dev, int table_nr,
+                                   const std::vector<uint16_t>& slope_table,
+                                   int steps)
+{
+    DBG_HELPER_ARGS(dbg, "table_nr = %d, steps = %d", table_nr, steps);
+  int i;
+  char msg[10000];
+
+  /* sanity check */
+  if(table_nr<0 || table_nr>4)
+    {
+        throw SaneException("invalid table number");
+    }
+
+  std::vector<uint8_t> table(steps * 2);
+  for (i = 0; i < steps; i++)
+    {
+      table[i * 2] = slope_table[i] & 0xff;
+      table[i * 2 + 1] = slope_table[i] >> 8;
+    }
+
+  if (DBG_LEVEL >= DBG_io)
+    {
+        std::sprintf(msg, "write slope %d (%d)=", table_nr, steps);
+        for (i = 0; i < steps; i++) {
+            std::sprintf(msg + std::strlen(msg), ",%d", slope_table[i]);
+        }
+      DBG (DBG_io, "%s: %s\n", __func__, msg);
+    }
+
+    if (dev->interface->is_mock()) {
+        dev->interface->record_slope_table(table_nr, slope_table);
+    }
+    // slope table addresses are fixed
+    dev->interface->write_ahb(0x10000000 + 0x4000 * table_nr, steps * 2, table.data());
+}
+
+/** @brief * Set register values of 'special' ti type frontend
+ * Registers value are taken from the frontend register data
+ * set.
+ * @param dev device owning the AFE
+ * @param set flag AFE_INIT to specify the AFE must be reset before writing data
+ * */
+static void gl124_set_ti_fe(Genesys_Device* dev, uint8_t set)
+{
+    DBG_HELPER(dbg);
+  int i;
+
+  if (set == AFE_INIT)
+    {
+        DBG(DBG_proc, "%s: setting DAC %u\n", __func__,
+            static_cast<unsigned>(dev->model->adc_id));
+
+      dev->frontend = dev->frontend_initial;
+    }
+
+    // start writing to DAC
+    dev->interface->write_fe_register(0x00, 0x80);
+
+  /* write values to analog frontend */
+  for (uint16_t addr = 0x01; addr < 0x04; addr++)
+    {
+        dev->interface->write_fe_register(addr, dev->frontend.regs.get_value(addr));
+    }
+
+    dev->interface->write_fe_register(0x04, 0x00);
+
+  /* these are not really sign for this AFE */
+  for (i = 0; i < 3; i++)
+    {
+        dev->interface->write_fe_register(0x05 + i, dev->frontend.regs.get_value(0x24 + i));
+    }
+
+    if (dev->model->adc_id == AdcId::CANON_LIDE_120) {
+        dev->interface->write_fe_register(0x00, 0x01);
+    }
+  else
+    {
+        dev->interface->write_fe_register(0x00, 0x11);
+    }
+}
+
+
+// Set values of analog frontend
+void CommandSetGl124::set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, uint8_t set) const
+{
+    DBG_HELPER_ARGS(dbg, "%s", set == AFE_INIT ? "init" :
+                               set == AFE_SET ? "set" :
+                               set == AFE_POWER_SAVE ? "powersave" : "huh?");
+    (void) sensor;
+  uint8_t val;
+
+  if (set == AFE_INIT)
+    {
+        DBG(DBG_proc, "%s(): setting DAC %u\n", __func__,
+            static_cast<unsigned>(dev->model->adc_id));
+      dev->frontend = dev->frontend_initial;
+    }
+
+    val = dev->interface->read_register(REG_0x0A);
+
+  /* route to correct analog FE */
+    switch ((val & REG_0x0A_SIFSEL) >> REG_0x0AS_SIFSEL) {
+    case 3:
+            gl124_set_ti_fe(dev, set);
+      break;
+    case 0:
+    case 1:
+    case 2:
+    default:
+            throw SaneException("unsupported analog FE 0x%02x", val);
+    }
+}
+
+static void gl124_init_motor_regs_scan(Genesys_Device* dev,
+                                       const Genesys_Sensor& sensor,
+                                       Genesys_Register_Set* reg,
+                                       const Motor_Profile& motor_profile,
+                                       unsigned int scan_exposure_time,
+                                       unsigned scan_yres,
+                                       unsigned int scan_lines,
+                                       unsigned int scan_dummy,
+                                       unsigned int feed_steps,
+                                       ScanColorMode scan_mode,
+                                       MotorFlag flags)
+{
+    DBG_HELPER(dbg);
+  int use_fast_fed;
+  unsigned int lincnt, fast_dpi;
+  unsigned int feedl,dist;
+  uint32_t z1, z2;
+    unsigned yres;
+    unsigned min_speed;
+  unsigned int linesel;
+
+    DBG(DBG_info, "%s : scan_exposure_time=%d, scan_yres=%d, step_type=%d, scan_lines=%d, "
+      "scan_dummy=%d, feed_steps=%d, scan_mode=%d, flags=%x\n", __func__, scan_exposure_time,
+        scan_yres, static_cast<unsigned>(motor_profile.step_type), scan_lines, scan_dummy,
+        feed_steps, static_cast<unsigned>(scan_mode),
+        static_cast<unsigned>(flags));
+
+  /* we never use fast fed since we do manual feed for the scans */
+  use_fast_fed=0;
+
+  /* enforce motor minimal scan speed
+   * @TODO extend motor struct for this value */
+  if (scan_mode == ScanColorMode::COLOR_SINGLE_PASS)
+    {
+      min_speed = 900;
+    }
+  else
+    {
+      switch(dev->model->motor_id)
+        {
+          case MotorId::CANON_LIDE_110:
+	    min_speed = 600;
+            break;
+          case MotorId::CANON_LIDE_120:
+            min_speed = 900;
+            break;
+          default:
+            min_speed = 900;
+            break;
+        }
+    }
+
+  /* compute min_speed and linesel */
+  if(scan_yres<min_speed)
+    {
+      yres=min_speed;
+        linesel = yres / scan_yres - 1;
+      /* limit case, we need a linesel > 0 */
+      if(linesel==0)
+        {
+          linesel=1;
+          yres=scan_yres*2;
+        }
+    }
+  else
+    {
+      yres=scan_yres;
+      linesel=0;
+    }
+
+    DBG(DBG_io2, "%s: final yres=%d, linesel=%d\n", __func__, yres, linesel);
+
+  lincnt=scan_lines*(linesel+1);
+    reg->set24(REG_LINCNT, lincnt);
+  DBG (DBG_io, "%s: lincnt=%d\n", __func__, lincnt);
+
+  /* compute register 02 value */
+    uint8_t r02 = REG_0x02_NOTHOME;
+
+    if (use_fast_fed) {
+        r02 |= REG_0x02_FASTFED;
+    } else {
+        r02 &= ~REG_0x02_FASTFED;
+    }
+
+    if (has_flag(flags, MotorFlag::AUTO_GO_HOME)) {
+        r02 |= REG_0x02_AGOHOME;
+    }
+
+    if (has_flag(flags, MotorFlag::DISABLE_BUFFER_FULL_MOVE) || (yres >= sensor.optical_res))
+    {
+        r02 |= REG_0x02_ACDCDIS;
+    }
+    if (has_flag(flags, MotorFlag::REVERSE)) {
+        r02 |= REG_0x02_MTRREV;
+    }
+
+    reg->set8(REG_0x02, r02);
+    sanei_genesys_set_motor_power(*reg, true);
+
+    reg->set16(REG_SCANFED, 4);
+
+  /* scan and backtracking slope table */
+    auto scan_table = sanei_genesys_slope_table(dev->model->asic_type, yres, scan_exposure_time,
+                                                dev->motor.base_ydpi, 1,
+                                                motor_profile);
+    gl124_send_slope_table(dev, SCAN_TABLE, scan_table.table, scan_table.steps_count);
+    gl124_send_slope_table(dev, BACKTRACK_TABLE, scan_table.table, scan_table.steps_count);
+
+    reg->set16(REG_STEPNO, scan_table.steps_count);
+
+  /* fast table */
+  fast_dpi=yres;
+
+  /*
+  if (scan_mode != ScanColorMode::COLOR_SINGLE_PASS)
+    {
+      fast_dpi*=3;
+    }
+    */
+    auto fast_table = sanei_genesys_slope_table(dev->model->asic_type, fast_dpi,
+                                                scan_exposure_time, dev->motor.base_ydpi,
+                                                1, motor_profile);
+    gl124_send_slope_table(dev, STOP_TABLE, fast_table.table, fast_table.steps_count);
+    gl124_send_slope_table(dev, FAST_TABLE, fast_table.table, fast_table.steps_count);
+
+    reg->set16(REG_FASTNO, fast_table.steps_count);
+    reg->set16(REG_FSHDEC, fast_table.steps_count);
+    reg->set16(REG_FMOVNO, fast_table.steps_count);
+
+  /* substract acceleration distance from feedl */
+  feedl=feed_steps;
+    feedl <<= static_cast<unsigned>(motor_profile.step_type);
+
+    dist = scan_table.steps_count;
+    if (has_flag(flags, MotorFlag::FEED)) {
+        dist *= 2;
+    }
+    if (use_fast_fed) {
+        dist += fast_table.steps_count * 2;
+    }
+  DBG (DBG_io2, "%s: acceleration distance=%d\n", __func__, dist);
+
+  /* get sure we don't use insane value */
+    if (dist < feedl) {
+        feedl -= dist;
+    } else {
+        feedl = 0;
+    }
+
+    reg->set24(REG_FEEDL, feedl);
+  DBG (DBG_io, "%s: feedl=%d\n", __func__, feedl);
+
+  /* doesn't seem to matter that much */
+    sanei_genesys_calculate_zmod(use_fast_fed,
+				  scan_exposure_time,
+                                 scan_table.table,
+                                 scan_table.steps_count,
+				  feedl,
+                                 scan_table.steps_count,
+                                  &z1,
+                                  &z2);
+
+    reg->set24(REG_Z1MOD, z1);
+  DBG(DBG_info, "%s: z1 = %d\n", __func__, z1);
+
+    reg->set24(REG_Z2MOD, z2);
+  DBG(DBG_info, "%s: z2 = %d\n", __func__, z2);
+
+  /* LINESEL */
+    reg->set8_mask(REG_0x1D, linesel, REG_0x1D_LINESEL);
+    reg->set8(REG_0xA0, (static_cast<unsigned>(motor_profile.step_type) << REG_0xA0S_STEPSEL) |
+                        (static_cast<unsigned>(motor_profile.step_type) << REG_0xA0S_FSTPSEL));
+
+    reg->set16(REG_FMOVDEC, fast_table.steps_count);
+}
+
+
+/** @brief copy sensor specific settings
+ * Set up register set for the given sensor resolution. Values are from the device table
+ * in genesys_devices.c for registers:
+ *       [0x16 ... 0x1d]
+ *       [0x52 ... 0x5e]
+ * Other come from the specific device sensor table in genesys_gl124.h:
+ *      0x18, 0x20, 0x61, 0x98 and
+ * @param dev device to set up
+ * @param regs register set to modify
+ * @param dpi resolution of the sensor during scan
+ * @param ccd_size_divisor flag for half ccd mode
+ * */
+static void gl124_setup_sensor(Genesys_Device* dev, const Genesys_Sensor& sensor,
+                               Genesys_Register_Set* regs)
+{
+    DBG_HELPER(dbg);
+
+    for (const auto& reg : sensor.custom_regs) {
+        regs->set8(reg.address, reg.value);
+    }
+
+    regs->set24(REG_EXPR, sensor.exposure.red);
+    regs->set24(REG_EXPG, sensor.exposure.green);
+    regs->set24(REG_EXPB, sensor.exposure.blue);
+
+    dev->segment_order = sensor.segment_order;
+}
+
+/** @brief setup optical related registers
+ * start and pixels are expressed in optical sensor resolution coordinate
+ * space.
+ * @param dev scanner device to use
+ * @param reg registers to set up
+ * @param exposure_time exposure time to use
+ * @param used_res scanning resolution used, may differ from
+ *        scan's one
+ * @param start logical start pixel coordinate
+ * @param pixels logical number of pixels to use
+ * @param channels number of color channels (currently 1 or 3)
+ * @param depth bit depth of the scan (1, 8 or 16)
+ * @param ccd_size_divisor whether sensor's timings are such that x coordinates must be halved
+ * @param color_filter color channel to use as gray data
+ * @param flags optical flags (@see )
+ */
+static void gl124_init_optical_regs_scan(Genesys_Device* dev, const Genesys_Sensor& sensor,
+                                         Genesys_Register_Set* reg, unsigned int exposure_time,
+                                         const ScanSession& session)
+{
+    DBG_HELPER_ARGS(dbg, "exposure_time=%d", exposure_time);
+    unsigned int dpihw;
+  GenesysRegister *r;
+  uint32_t expmax;
+
+    // resolution is divided according to ccd_pixels_per_system_pixel
+    unsigned ccd_pixels_per_system_pixel = sensor.ccd_pixels_per_system_pixel();
+    DBG(DBG_io2, "%s: ccd_pixels_per_system_pixel=%d\n", __func__, ccd_pixels_per_system_pixel);
+
+    // to manage high resolution device while keeping good low resolution scanning speed, we
+    // make hardware dpi vary
+    dpihw = sensor.get_register_hwdpi(session.output_resolution * ccd_pixels_per_system_pixel);
+    DBG(DBG_io2, "%s: dpihw=%d\n", __func__, dpihw);
+
+    gl124_setup_sensor(dev, sensor, reg);
+
+    dev->cmd_set->set_fe(dev, sensor, AFE_SET);
+
+  /* enable shading */
+    regs_set_optical_off(dev->model->asic_type, *reg);
+    r = sanei_genesys_get_address (reg, REG_0x01);
+    if (has_flag(session.params.flags, ScanFlag::DISABLE_SHADING) ||
+        (dev->model->flags & GENESYS_FLAG_NO_CALIBRATION))
+    {
+        r->value &= ~REG_0x01_DVDSET;
+    } else {
+        r->value |= REG_0x01_DVDSET;
+    }
+
+    r = sanei_genesys_get_address(reg, REG_0x03);
+    if ((dev->model->sensor_id != SensorId::CIS_CANON_LIDE_120) && (session.params.xres>=600)) {
+        r->value &= ~REG_0x03_AVEENB;
+      DBG (DBG_io, "%s: disabling AVEENB\n", __func__);
+    }
+  else
+    {
+        r->value |= ~REG_0x03_AVEENB;
+      DBG (DBG_io, "%s: enabling AVEENB\n", __func__);
+    }
+
+    sanei_genesys_set_lamp_power(dev, sensor, *reg,
+                                 !has_flag(session.params.flags, ScanFlag::DISABLE_LAMP));
+
+    // BW threshold
+    dev->interface->write_register(REG_0x114, dev->settings.threshold);
+    dev->interface->write_register(REG_0x115, dev->settings.threshold);
+
+  /* monochrome / color scan */
+    r = sanei_genesys_get_address (reg, REG_0x04);
+    switch (session.params.depth) {
+    case 8:
+            r->value &= ~(REG_0x04_LINEART | REG_0x04_BITSET);
+            break;
+    case 16:
+            r->value &= ~REG_0x04_LINEART;
+            r->value |= REG_0x04_BITSET;
+            break;
+    }
+
+    r->value &= ~REG_0x04_FILTER;
+  if (session.params.channels == 1)
+    {
+      switch (session.params.color_filter)
+	{
+            case ColorFilter::RED:
+                r->value |= 0x10;
+                break;
+            case ColorFilter::BLUE:
+                r->value |= 0x30;
+                break;
+            case ColorFilter::GREEN:
+                r->value |= 0x20;
+                break;
+            default:
+                break; // should not happen
+	}
+    }
+
+    sanei_genesys_set_dpihw(*reg, sensor, dpihw);
+
+    if (should_enable_gamma(session, sensor)) {
+        reg->find_reg(REG_0x05).value |= REG_0x05_GMMENB;
+    } else {
+        reg->find_reg(REG_0x05).value &= ~REG_0x05_GMMENB;
+    }
+
+    unsigned dpiset_reg = session.output_resolution * ccd_pixels_per_system_pixel *
+            session.ccd_size_divisor;
+    if (sensor.dpiset_override != 0) {
+        dpiset_reg = sensor.dpiset_override;
+    }
+
+    reg->set16(REG_DPISET, dpiset_reg);
+    DBG (DBG_io2, "%s: dpiset used=%d\n", __func__, dpiset_reg);
+
+    r = sanei_genesys_get_address(reg, REG_0x06);
+    r->value |= REG_0x06_GAIN4;
+
+  /* CIS scanners can do true gray by setting LEDADD */
+  /* we set up LEDADD only when asked */
+    if (dev->model->is_cis) {
+        r = sanei_genesys_get_address (reg, REG_0x60);
+        r->value &= ~REG_0x60_LEDADD;
+        if (session.enable_ledadd) {
+            r->value |= REG_0x60_LEDADD;
+            expmax = reg->get24(REG_EXPR);
+            expmax = std::max(expmax, reg->get24(REG_EXPG));
+            expmax = std::max(expmax, reg->get24(REG_EXPB));
+
+            dev->reg.set24(REG_EXPR, expmax);
+            dev->reg.set24(REG_EXPG, expmax);
+            dev->reg.set24(REG_EXPB, expmax);
+        }
+      /* RGB weighting, REG_TRUER,G and B are to be set  */
+        r = sanei_genesys_get_address (reg, 0x01);
+        r->value &= ~REG_0x01_TRUEGRAY;
+        if (session.enable_ledadd) {
+            r->value |= REG_0x01_TRUEGRAY;
+            dev->interface->write_register(REG_TRUER, 0x80);
+            dev->interface->write_register(REG_TRUEG, 0x80);
+            dev->interface->write_register(REG_TRUEB, 0x80);
+        }
+    }
+
+    reg->set24(REG_STRPIXEL, session.pixel_startx);
+    reg->set24(REG_ENDPIXEL, session.pixel_endx);
+
+  dev->line_count = 0;
+
+    build_image_pipeline(dev, session);
+
+    // MAXWD is expressed in 2 words unit
+
+    // BUG: we shouldn't multiply by channels here
+    reg->set24(REG_MAXWD, session.output_line_bytes_raw / session.ccd_size_divisor * session.params.channels);
+
+    reg->set24(REG_LPERIOD, exposure_time);
+  DBG (DBG_io2, "%s: exposure_time used=%d\n", __func__, exposure_time);
+
+    reg->set16(REG_DUMMY, sensor.dummy_pixel);
+}
+
+void CommandSetGl124::init_regs_for_scan_session(Genesys_Device* dev, const Genesys_Sensor& sensor,
+                                                 Genesys_Register_Set* reg,
+                                                 const ScanSession& session) const
+{
+    DBG_HELPER(dbg);
+    session.assert_computed();
+
+  int move;
+  int exposure_time;
+
+  int dummy = 0;
+  int slope_dpi = 0;
+
+    /* cis color scan is effectively a gray scan with 3 gray lines per color line and a FILTER of 0 */
+    if (dev->model->is_cis) {
+        slope_dpi = session.params.yres * session.params.channels;
+    } else {
+        slope_dpi = session.params.yres;
+    }
+
+    if (has_flag(session.params.flags, ScanFlag::FEEDING)) {
+        exposure_time = 2304;
+    } else {
+        exposure_time = sensor.exposure_lperiod;
+    }
+    const auto& motor_profile = sanei_genesys_get_motor_profile(*gl124_motor_profiles,
+                                                                dev->model->motor_id,
+                                                                exposure_time);
+
+  DBG(DBG_info, "%s : exposure_time=%d pixels\n", __func__, exposure_time);
+  DBG(DBG_info, "%s : scan_step_type=%d\n", __func__, static_cast<unsigned>(motor_profile.step_type));
+
+  /* we enable true gray for cis scanners only, and just when doing
+   * scan since color calibration is OK for this mode
+   */
+
+    // now _LOGICAL_ optical values used are known, setup registers
+    gl124_init_optical_regs_scan(dev, sensor, reg, exposure_time, session);
+
+  /* add tl_y to base movement */
+    move = session.params.starty;
+  DBG(DBG_info, "%s: move=%d steps\n", __func__, move);
+
+    MotorFlag mflags = MotorFlag::NONE;
+    if (has_flag(session.params.flags, ScanFlag::DISABLE_BUFFER_FULL_MOVE)) {
+        mflags |= MotorFlag::DISABLE_BUFFER_FULL_MOVE;
+    }
+    if (has_flag(session.params.flags, ScanFlag::FEEDING)) {
+        mflags |= MotorFlag::FEED;
+    }
+    if (has_flag(session.params.flags, ScanFlag::REVERSE)) {
+        mflags |= MotorFlag::REVERSE;
+    }
+    gl124_init_motor_regs_scan(dev, sensor, reg, motor_profile, exposure_time, slope_dpi,
+                               dev->model->is_cis ? session.output_line_count * session.params.channels :
+                                                    session.output_line_count,
+                               dummy, move, session.params.scan_mode, mflags);
+
+  /*** prepares data reordering ***/
+
+    dev->read_buffer.clear();
+    dev->read_buffer.alloc(session.buffer_size_read);
+
+    dev->read_active = true;
+
+    dev->session = session;
+
+    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 = %zu\n", __func__,
+        dev->total_bytes_to_read);
+}
+
+ScanSession CommandSetGl124::calculate_scan_session(const Genesys_Device* dev,
+                                                    const Genesys_Sensor& sensor,
+                                                    const Genesys_Settings& settings) const
+{
+  int start;
+
+    DBG(DBG_info, "%s ", __func__);
+    debug_dump(DBG_info, settings);
+
+  /* start */
+    start = static_cast<int>(dev->model->x_offset);
+    start += static_cast<int>(settings.tl_x);
+    start = static_cast<int>((start * sensor.optical_res) / MM_PER_INCH);
+
+    ScanSession session;
+    session.params.xres = settings.xres;
+    session.params.yres = settings.yres;
+    session.params.startx = start;
+    session.params.starty = 0; // not used
+    session.params.pixels = settings.pixels;
+    session.params.requested_pixels = settings.requested_pixels;
+    session.params.lines = settings.lines;
+    session.params.depth = settings.depth;
+    session.params.channels = settings.get_channels();
+    session.params.scan_method = settings.scan_method;
+    session.params.scan_mode = settings.scan_mode;
+    session.params.color_filter = settings.color_filter;
+    session.params.flags = ScanFlag::NONE;
+
+    compute_session(dev, session, sensor);
+
+    return session;
+}
+
+/**
+ * for fast power saving methods only, like disabling certain amplifiers
+ * @param dev device to use
+ * @param enable true to set inot powersaving
+ * */
+void CommandSetGl124::save_power(Genesys_Device* dev, bool enable) const
+{
+    (void) dev;
+    DBG_HELPER_ARGS(dbg, "enable = %d", enable);
+}
+
+void CommandSetGl124::set_powersaving(Genesys_Device* dev, int delay /* in minutes */) const
+{
+    DBG_HELPER_ARGS(dbg,  "delay = %d",  delay);
+  GenesysRegister *r;
+
+    r = sanei_genesys_get_address(&dev->reg, REG_0x03);
+  r->value &= ~0xf0;
+  if(delay<15)
+    {
+      r->value |= delay;
+    }
+  else
+    {
+      r->value |= 0x0f;
+    }
+}
+
+/** @brief setup GPIOs for scan
+ * Setup GPIO values to drive motor (or light) needed for the
+ * target resolution
+ * @param *dev device to set up
+ * @param resolution dpi of the target scan
+ */
+void gl124_setup_scan_gpio(Genesys_Device* dev, int resolution)
+{
+    DBG_HELPER(dbg);
+
+    uint8_t val = dev->interface->read_register(REG_0x32);
+
+  /* LiDE 110, 210 and 220 cases */
+    if(dev->model->gpio_id != GpioId::CANON_LIDE_120) {
+      if(resolution>=dev->motor.base_ydpi/2)
+	{
+	  val &= 0xf7;
+	}
+      else if(resolution>=dev->motor.base_ydpi/4)
+	{
+	  val &= 0xef;
+	}
+      else
+	{
+	  val |= 0x10;
+	}
+    }
+  /* 120 : <=300 => 0x53 */
+  else
+    { /* base_ydpi is 4800 */
+      if(resolution<=300)
+	{
+	  val &= 0xf7;
+	}
+      else if(resolution<=600)
+	{
+	  val |= 0x08;
+	}
+      else if(resolution<=1200)
+	{
+	  val &= 0xef;
+	  val |= 0x08;
+	}
+      else
+	{
+	  val &= 0xf7;
+	}
+    }
+  val |= 0x02;
+    dev->interface->write_register(REG_0x32, val);
+}
+
+// Send the low-level scan command
+// todo: is this that useful ?
+void CommandSetGl124::begin_scan(Genesys_Device* dev, const Genesys_Sensor& sensor,
+                                 Genesys_Register_Set* reg, bool start_motor) const
+{
+    DBG_HELPER(dbg);
+    (void) sensor;
+    (void) reg;
+
+    // set up GPIO for scan
+    gl124_setup_scan_gpio(dev,dev->settings.yres);
+
+    // clear scan and feed count
+    dev->interface->write_register(REG_0x0D, REG_0x0D_CLRLNCNT | REG_0x0D_CLRMCNT);
+
+    // enable scan and motor
+    uint8_t val = dev->interface->read_register(REG_0x01);
+    val |= REG_0x01_SCAN;
+    dev->interface->write_register(REG_0x01, val);
+
+    scanner_start_action(*dev, start_motor);
+
+    dev->advance_head_pos_by_session(ScanHeadId::PRIMARY);
+}
+
+
+// Send the stop scan command
+void CommandSetGl124::end_scan(Genesys_Device* dev, Genesys_Register_Set* reg,
+                               bool check_stop) const
+{
+    (void) reg;
+    DBG_HELPER_ARGS(dbg, "check_stop = %d", check_stop);
+
+    if (!dev->model->is_sheetfed) {
+        scanner_stop_action(*dev);
+    }
+}
+
+
+/** Park head
+ * Moves the slider to the home (top) position slowly
+ * @param dev device to park
+ * @param wait_until_home true to make the function waiting for head
+ * to be home before returning, if fals returne immediately
+ */
+void CommandSetGl124::move_back_home(Genesys_Device* dev, bool wait_until_home) const
+{
+    scanner_move_back_home(*dev, wait_until_home);
+}
+
+// Automatically set top-left edge of the scan area by scanning a 200x200 pixels area at 600 dpi
+// from very top of scanner
+void CommandSetGl124::search_start_position(Genesys_Device* dev) const
+{
+    DBG_HELPER(dbg);
+  int size;
+  Genesys_Register_Set local_reg = dev->reg;
+
+  int pixels = 600;
+  int dpi = 300;
+
+  /* sets for a 200 lines * 600 pixels */
+  /* normal scan with no shading */
+
+    // FIXME: the current approach of doing search only for one resolution does not work on scanners
+    // whith employ different sensors with potentially different settings.
+    const auto& sensor = sanei_genesys_find_sensor(dev, dpi, 1, ScanMethod::FLATBED);
+
+    ScanSession session;
+    session.params.xres = dpi;
+    session.params.yres = dpi;
+    session.params.startx = 0;
+    session.params.starty = 0;        /*we should give a small offset here~60 steps */
+    session.params.pixels = 600;
+    session.params.lines = dev->model->search_lines;
+    session.params.depth = 8;
+    session.params.channels = 1;
+    session.params.scan_method = dev->settings.scan_method;
+    session.params.scan_mode = ScanColorMode::GRAY;
+    session.params.color_filter = ColorFilter::GREEN;
+    session.params.flags = ScanFlag::DISABLE_SHADING |
+                           ScanFlag::DISABLE_GAMMA |
+                           ScanFlag::IGNORE_LINE_DISTANCE |
+                           ScanFlag::DISABLE_BUFFER_FULL_MOVE;
+    compute_session(dev, session, sensor);
+
+    init_regs_for_scan_session(dev, sensor, &local_reg, session);
+
+    // send to scanner
+    dev->interface->write_registers(local_reg);
+
+  size = pixels * dev->model->search_lines;
+
+  std::vector<uint8_t> data(size);
+
+    begin_scan(dev, sensor, &local_reg, true);
+
+    if (is_testing_mode()) {
+        dev->interface->test_checkpoint("search_start_position");
+        end_scan(dev, &local_reg, true);
+        dev->reg = local_reg;
+        return;
+    }
+
+    wait_until_buffer_non_empty(dev);
+
+    // now we're on target, we can read data
+    sanei_genesys_read_data_from_scanner(dev, data.data(), size);
+
+    if (DBG_LEVEL >= DBG_data) {
+        sanei_genesys_write_pnm_file("gl124_search_position.pnm", data.data(), 8, 1, pixels,
+                                     dev->model->search_lines);
+    }
+
+    end_scan(dev, &local_reg, true);
+
+  /* update regs to copy ASIC internal state */
+  dev->reg = local_reg;
+
+    for (auto& sensor_update :
+             sanei_genesys_find_sensors_all_for_write(dev, dev->model->default_method))
+    {
+        sanei_genesys_search_reference_point(dev, sensor_update, data.data(), 0, dpi, pixels,
+                                             dev->model->search_lines);
+    }
+}
+
+// sets up register for coarse gain calibration
+// todo: check it for scanners using it
+void CommandSetGl124::init_regs_for_coarse_calibration(Genesys_Device* dev,
+                                                       const Genesys_Sensor& sensor,
+                                                       Genesys_Register_Set& regs) const
+{
+    DBG_HELPER(dbg);
+
+    ScanSession session;
+    session.params.xres = dev->settings.xres;
+    session.params.yres = dev->settings.yres;
+    session.params.startx = 0;
+    session.params.starty = 0;
+    session.params.pixels = sensor.optical_res / sensor.ccd_pixels_per_system_pixel();
+    session.params.lines = 20;
+    session.params.depth = 16;
+    session.params.channels = dev->settings.get_channels();
+    session.params.scan_method = dev->settings.scan_method;
+    session.params.scan_mode = dev->settings.scan_mode;
+    session.params.color_filter = dev->settings.color_filter;
+    session.params.flags = ScanFlag::DISABLE_SHADING |
+                           ScanFlag::DISABLE_GAMMA |
+                           ScanFlag::SINGLE_LINE |
+                           ScanFlag::FEEDING |
+                           ScanFlag::IGNORE_LINE_DISTANCE;
+    compute_session(dev, session, sensor);
+
+    init_regs_for_scan_session(dev, sensor, &regs, session);
+
+  sanei_genesys_set_motor_power(regs, false);
+
+  DBG(DBG_info, "%s: optical sensor res: %d dpi, actual res: %d\n", __func__,
+      sensor.optical_res / sensor.ccd_pixels_per_system_pixel(), dev->settings.xres);
+
+    dev->interface->write_registers(regs);
+}
+
+
+// init registers for shading calibration shading calibration is done at dpihw
+void CommandSetGl124::init_regs_for_shading(Genesys_Device* dev, const Genesys_Sensor& sensor,
+                                            Genesys_Register_Set& regs) const
+{
+    DBG_HELPER(dbg);
+  int move, resolution, dpihw, factor;
+
+  /* initial calibration reg values */
+  regs = dev->reg;
+
+  dev->calib_channels = 3;
+  dev->calib_lines = dev->model->shading_lines;
+    dpihw = sensor.get_register_hwdpi(dev->settings.xres);
+  if(dpihw>=2400)
+    {
+      dev->calib_lines *= 2;
+    }
+  resolution=dpihw;
+
+    unsigned ccd_size_divisor = sensor.get_ccd_size_divisor_for_dpi(dev->settings.xres);
+
+    resolution /= ccd_size_divisor;
+    dev->calib_lines /= ccd_size_divisor; // reducing just because we reduced the resolution
+
+    const auto& calib_sensor = sanei_genesys_find_sensor(dev, resolution,
+                                                         dev->calib_channels,
+                                                         dev->settings.scan_method);
+  dev->calib_resolution = resolution;
+  dev->calib_total_bytes_to_read = 0;
+    factor = calib_sensor.optical_res / resolution;
+    dev->calib_pixels = calib_sensor.sensor_pixels / factor;
+
+  /* distance to move to reach white target at high resolution */
+  move=0;
+    if (dev->settings.yres >= 1200) {
+        move = static_cast<int>(dev->model->y_offset_calib_white);
+        move = static_cast<int>((move * (dev->motor.base_ydpi/4)) / MM_PER_INCH);
+    }
+  DBG (DBG_io, "%s: move=%d steps\n", __func__, move);
+
+    ScanSession session;
+    session.params.xres = resolution;
+    session.params.yres = resolution;
+    session.params.startx = 0;
+    session.params.starty = move;
+    session.params.pixels = dev->calib_pixels;
+    session.params.lines = dev->calib_lines;
+    session.params.depth = 16;
+    session.params.channels = dev->calib_channels;
+    session.params.scan_method = dev->settings.scan_method;
+    session.params.scan_mode = ScanColorMode::COLOR_SINGLE_PASS;
+    session.params.color_filter = ColorFilter::RED;
+    session.params.flags = ScanFlag::DISABLE_SHADING |
+                           ScanFlag::DISABLE_GAMMA |
+                           ScanFlag::DISABLE_BUFFER_FULL_MOVE |
+                           ScanFlag::IGNORE_LINE_DISTANCE;
+    compute_session(dev, session, calib_sensor);
+
+    try {
+        init_regs_for_scan_session(dev, calib_sensor, &regs, session);
+    } catch (...) {
+        catch_all_exceptions(__func__, [&](){ sanei_genesys_set_motor_power(regs, false); });
+        throw;
+    }
+    sanei_genesys_set_motor_power(regs, false);
+
+    dev->interface->write_registers(regs);
+}
+
+void CommandSetGl124::wait_for_motor_stop(Genesys_Device* dev) const
+{
+    DBG_HELPER(dbg);
+
+    auto status = scanner_read_status(*dev);
+    uint8_t val40 = dev->interface->read_register(REG_0x100);
+
+    if (!status.is_motor_enabled && (val40 & REG_0x100_MOTMFLG) == 0) {
+        return;
+    }
+
+    do {
+        dev->interface->sleep_ms(10);
+        status = scanner_read_status(*dev);
+        val40 = dev->interface->read_register(REG_0x100);
+    } while (status.is_motor_enabled ||(val40 & REG_0x100_MOTMFLG));
+    dev->interface->sleep_ms(50);
+}
+
+/** @brief set up registers for the actual scan
+ */
+void CommandSetGl124::init_regs_for_scan(Genesys_Device* dev, const Genesys_Sensor& sensor) const
+{
+    DBG_HELPER(dbg);
+  float move;
+  int move_dpi;
+  float start;
+
+    debug_dump(DBG_info, dev->settings);
+
+  /* y (motor) distance to move to reach scanned area */
+  move_dpi = dev->motor.base_ydpi/4;
+    move = static_cast<float>(dev->model->y_offset);
+    move += static_cast<float>(dev->settings.tl_y);
+    move = static_cast<float>((move * move_dpi) / MM_PER_INCH);
+  DBG (DBG_info, "%s: move=%f steps\n", __func__, move);
+
+    if (dev->settings.get_channels() * dev->settings.yres >= 600 && move > 700) {
+        scanner_move(*dev, dev->model->default_method, static_cast<unsigned>(move - 500),
+                     Direction::FORWARD);
+      move=500;
+    }
+  DBG(DBG_info, "%s: move=%f steps\n", __func__, move);
+
+  /* start */
+    start = static_cast<float>(dev->model->x_offset);
+    start += static_cast<float>(dev->settings.tl_x);
+    start /= sensor.get_ccd_size_divisor_for_dpi(dev->settings.xres);
+    start = static_cast<float>((start * sensor.optical_res) / MM_PER_INCH);
+
+    ScanSession session;
+    session.params.xres = dev->settings.xres;
+    session.params.yres = dev->settings.yres;
+    session.params.startx = static_cast<unsigned>(start);
+    session.params.starty = static_cast<unsigned>(move);
+    session.params.pixels = dev->settings.pixels;
+    session.params.requested_pixels = dev->settings.requested_pixels;
+    session.params.lines = dev->settings.lines;
+    session.params.depth = dev->settings.depth;
+    session.params.channels = dev->settings.get_channels();
+    session.params.scan_method = dev->settings.scan_method;
+    session.params.scan_mode = dev->settings.scan_mode;
+    session.params.color_filter = dev->settings.color_filter;
+    session.params.flags = ScanFlag::NONE;
+    compute_session(dev, session, sensor);
+
+    init_regs_for_scan_session(dev, sensor, &dev->reg, session);
+}
+
+/**
+ * Send shading calibration data. The buffer is considered to always hold values
+ * for all the channels.
+ */
+void CommandSetGl124::send_shading_data(Genesys_Device* dev, const Genesys_Sensor& sensor,
+                                        std::uint8_t* data, int size) const
+{
+    DBG_HELPER_ARGS(dbg, "writing %d bytes of shading data", size);
+    uint32_t addr, length, x, factor, segcnt, pixels, i;
+  uint16_t dpiset,dpihw;
+    uint8_t *ptr, *src;
+
+  /* logical size of a color as seen by generic code of the frontend */
+    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);
+  if(endpixel==0)
+    {
+      endpixel=segcnt;
+    }
+
+  /* compute deletion factor */
+    dpiset = dev->reg.get16(REG_DPISET);
+    dpihw = sensor.get_register_hwdpi(dpiset);
+  factor=dpihw/dpiset;
+  DBG( DBG_io2, "%s: factor=%d\n",__func__,factor);
+
+  /* turn pixel value into bytes 2x16 bits words */
+  strpixel*=2*2; /* 2 words of 2 bytes */
+  endpixel*=2*2;
+  segcnt*=2*2;
+  pixels=endpixel-strpixel;
+
+    dev->interface->record_key_value("shading_start_pixel", std::to_string(strpixel));
+    dev->interface->record_key_value("shading_pixels", std::to_string(pixels));
+    dev->interface->record_key_value("shading_length", std::to_string(length));
+    dev->interface->record_key_value("shading_factor", std::to_string(factor));
+    dev->interface->record_key_value("shading_segcnt", std::to_string(segcnt));
+    dev->interface->record_key_value("shading_segment_count",
+                                     std::to_string(dev->session.segment_count));
+
+  DBG( DBG_io2, "%s: using chunks of %d bytes (%d shading data pixels)\n",__func__,length, length/4);
+    std::vector<uint8_t> buffer(pixels * dev->session.segment_count, 0);
+
+  /* write actual red data */
+  for(i=0;i<3;i++)
+    {
+      /* copy data to work buffer and process it */
+          /* coefficent destination */
+      ptr = buffer.data();
+
+      /* iterate on both sensor segment */
+      for(x=0;x<pixels;x+=4*factor)
+        {
+          /* coefficient source */
+          src=data+x+strpixel+i*length;
+
+          /* iterate over all the segments */
+            switch (dev->session.segment_count) {
+            case 1:
+              ptr[0+pixels*0]=src[0+segcnt*0];
+              ptr[1+pixels*0]=src[1+segcnt*0];
+              ptr[2+pixels*0]=src[2+segcnt*0];
+              ptr[3+pixels*0]=src[3+segcnt*0];
+              break;
+            case 2:
+              ptr[0+pixels*0]=src[0+segcnt*0];
+              ptr[1+pixels*0]=src[1+segcnt*0];
+              ptr[2+pixels*0]=src[2+segcnt*0];
+              ptr[3+pixels*0]=src[3+segcnt*0];
+              ptr[0+pixels*1]=src[0+segcnt*1];
+              ptr[1+pixels*1]=src[1+segcnt*1];
+              ptr[2+pixels*1]=src[2+segcnt*1];
+              ptr[3+pixels*1]=src[3+segcnt*1];
+              break;
+            case 4:
+              ptr[0+pixels*0]=src[0+segcnt*0];
+              ptr[1+pixels*0]=src[1+segcnt*0];
+              ptr[2+pixels*0]=src[2+segcnt*0];
+              ptr[3+pixels*0]=src[3+segcnt*0];
+              ptr[0+pixels*1]=src[0+segcnt*2];
+              ptr[1+pixels*1]=src[1+segcnt*2];
+              ptr[2+pixels*1]=src[2+segcnt*2];
+              ptr[3+pixels*1]=src[3+segcnt*2];
+              ptr[0+pixels*2]=src[0+segcnt*1];
+              ptr[1+pixels*2]=src[1+segcnt*1];
+              ptr[2+pixels*2]=src[2+segcnt*1];
+              ptr[3+pixels*2]=src[3+segcnt*1];
+              ptr[0+pixels*3]=src[0+segcnt*3];
+              ptr[1+pixels*3]=src[1+segcnt*3];
+              ptr[2+pixels*3]=src[2+segcnt*3];
+              ptr[3+pixels*3]=src[3+segcnt*3];
+              break;
+            }
+
+          /* next shading coefficient */
+          ptr+=4;
+        }
+        uint8_t val = dev->interface->read_register(0xd0+i);
+      addr = val * 8192 + 0x10000000;
+        dev->interface->write_ahb(addr, pixels * dev->session.segment_count, buffer.data());
+    }
+}
+
+
+/** @brief move to calibration area
+ * This functions moves scanning head to calibration area
+ * by doing a 600 dpi scan
+ * @param dev scanner device
+ */
+static void move_to_calibration_area(Genesys_Device* dev, const Genesys_Sensor& sensor,
+                                     Genesys_Register_Set& regs)
+{
+    (void) sensor;
+
+    DBG_HELPER(dbg);
+  int pixels;
+  int size;
+
+    unsigned resolution = 600;
+    unsigned channels = 3;
+    const auto& move_sensor = sanei_genesys_find_sensor(dev, resolution, channels,
+                                                         dev->settings.scan_method);
+    pixels = (move_sensor.sensor_pixels * 600) / move_sensor.optical_res;
+
+  /* initial calibration reg values */
+  regs = dev->reg;
+
+    ScanSession session;
+    session.params.xres = resolution;
+    session.params.yres = resolution;
+    session.params.startx = 0;
+    session.params.starty = 0;
+    session.params.pixels = pixels;
+    session.params.lines = 1;
+    session.params.depth = 8;
+    session.params.channels = channels;
+    session.params.scan_method = dev->settings.scan_method;
+    session.params.scan_mode = ScanColorMode::COLOR_SINGLE_PASS;
+    session.params.color_filter = dev->settings.color_filter;
+    session.params.flags = ScanFlag::DISABLE_SHADING |
+                           ScanFlag::DISABLE_GAMMA |
+                           ScanFlag::SINGLE_LINE |
+                           ScanFlag::IGNORE_LINE_DISTANCE;
+    compute_session(dev, session, move_sensor);
+
+    dev->cmd_set->init_regs_for_scan_session(dev, move_sensor, &regs, session);
+
+  size = pixels * 3;
+  std::vector<uint8_t> line(size);
+
+    // write registers and scan data
+    dev->interface->write_registers(regs);
+
+  DBG (DBG_info, "%s: starting line reading\n", __func__);
+    dev->cmd_set->begin_scan(dev, move_sensor, &regs, true);
+
+    if (is_testing_mode()) {
+        dev->interface->test_checkpoint("move_to_calibration_area");
+        scanner_stop_action(*dev);
+        return;
+    }
+
+    sanei_genesys_read_data_from_scanner(dev, line.data(), size);
+
+    // stop scanning
+    scanner_stop_action(*dev);
+
+  if (DBG_LEVEL >= DBG_data)
+    {
+      sanei_genesys_write_pnm_file("gl124_movetocalarea.pnm", line.data(), 8, 3, pixels, 1);
+    }
+}
+
+/* this function does the led calibration by scanning one line of the calibration
+   area below scanner's top on white strip.
+
+-needs working coarse/gain
+*/
+SensorExposure CommandSetGl124::led_calibration(Genesys_Device* dev, const Genesys_Sensor& sensor,
+                                                Genesys_Register_Set& regs) const
+{
+    DBG_HELPER(dbg);
+  int num_pixels;
+  int total_size;
+  int resolution;
+  int dpihw;
+  int i, j;
+  int val;
+  int channels;
+  int avg[3];
+  int turn;
+  uint16_t exp[3],target;
+
+  /* move to calibration area */
+  move_to_calibration_area(dev, sensor, regs);
+
+  /* offset calibration is always done in 16 bit depth color mode */
+  channels = 3;
+    dpihw = sensor.get_register_hwdpi(dev->settings.xres);
+    resolution = dpihw;
+    unsigned ccd_size_divisor = sensor.get_ccd_size_divisor_for_dpi(dev->settings.xres);
+    resolution /= ccd_size_divisor;
+
+    const auto& calib_sensor = sanei_genesys_find_sensor(dev, resolution, channels,
+                                                         dev->settings.scan_method);
+    num_pixels = (calib_sensor.sensor_pixels * resolution) / calib_sensor.optical_res;
+
+  /* initial calibration reg values */
+  regs = dev->reg;
+
+    ScanSession session;
+    session.params.xres = resolution;
+    session.params.yres = resolution;
+    session.params.startx = 0;
+    session.params.starty = 0;
+    session.params.pixels = num_pixels;
+    session.params.lines = 1;
+    session.params.depth = 16;
+    session.params.channels = channels;
+    session.params.scan_method = dev->settings.scan_method;
+    session.params.scan_mode = ScanColorMode::COLOR_SINGLE_PASS;
+    session.params.color_filter = dev->settings.color_filter;
+    session.params.flags = ScanFlag::DISABLE_SHADING |
+                           ScanFlag::DISABLE_GAMMA |
+                           ScanFlag::SINGLE_LINE |
+                           ScanFlag::IGNORE_LINE_DISTANCE;
+    compute_session(dev, session, calib_sensor);
+
+    init_regs_for_scan_session(dev, calib_sensor, &regs, session);
+
+    total_size = num_pixels * channels * (session.params.depth / 8) * 1;
+  std::vector<uint8_t> line(total_size);
+
+    // initial loop values and boundaries
+    exp[0] = calib_sensor.exposure.red;
+    exp[1] = calib_sensor.exposure.green;
+    exp[2] = calib_sensor.exposure.blue;
+  target=sensor.gain_white_ref*256;
+
+  turn = 0;
+
+  /* no move during led calibration */
+  sanei_genesys_set_motor_power(regs, false);
+    bool acceptable = false;
+  do
+    {
+        // set up exposure
+        regs.set24(REG_EXPR, exp[0]);
+        regs.set24(REG_EXPG, exp[1]);
+        regs.set24(REG_EXPB, exp[2]);
+
+        // write registers and scan data
+        dev->interface->write_registers(regs);
+
+      DBG(DBG_info, "%s: starting line reading\n", __func__);
+        begin_scan(dev, calib_sensor, &regs, true);
+
+        if (is_testing_mode()) {
+            dev->interface->test_checkpoint("led_calibration");
+            scanner_stop_action(*dev);
+            return calib_sensor.exposure;
+        }
+
+        sanei_genesys_read_data_from_scanner(dev, line.data(), total_size);
+
+        // stop scanning
+        scanner_stop_action(*dev);
+
+      if (DBG_LEVEL >= DBG_data)
+	{
+          char fn[30];
+          std::snprintf(fn, 30, "gl124_led_%02d.pnm", turn);
+          sanei_genesys_write_pnm_file(fn, line.data(), session.params.depth, channels, num_pixels,
+                                       1);
+	}
+
+      /* compute average */
+      for (j = 0; j < channels; j++)
+	{
+	  avg[j] = 0;
+	  for (i = 0; i < num_pixels; i++)
+	    {
+	      if (dev->model->is_cis)
+		val =
+		  line[i * 2 + j * 2 * num_pixels + 1] * 256 +
+		  line[i * 2 + j * 2 * num_pixels];
+	      else
+		val =
+		  line[i * 2 * channels + 2 * j + 1] * 256 +
+		  line[i * 2 * channels + 2 * j];
+	      avg[j] += val;
+	    }
+
+	  avg[j] /= num_pixels;
+	}
+
+      DBG(DBG_info, "%s: average: %d,%d,%d\n", __func__, avg[0], avg[1], avg[2]);
+
+      /* check if exposure gives average within the boundaries */
+        acceptable = true;
+      for(i=0;i<3;i++)
+        {
+          /* we accept +- 2% delta from target */
+          if(abs(avg[i]-target)>target/50)
+            {
+                float prev_weight = 0.5;
+                exp[i] = exp[i] * prev_weight + ((exp[i] * target) / avg[i]) * (1 - prev_weight);
+                acceptable = false;
+            }
+        }
+
+      turn++;
+    }
+  while (!acceptable && turn < 100);
+
+  DBG(DBG_info, "%s: acceptable exposure: %d,%d,%d\n", __func__, exp[0], exp[1], exp[2]);
+
+    // set these values as final ones for scan
+    dev->reg.set24(REG_EXPR, exp[0]);
+    dev->reg.set24(REG_EXPG, exp[1]);
+    dev->reg.set24(REG_EXPB, exp[2]);
+
+    return { exp[0], exp[1], exp[2] };
+}
+
+/**
+ * average dark pixels of a 8 bits scan
+ */
+static int
+dark_average (uint8_t * data, unsigned int pixels, unsigned int lines,
+	      unsigned int channels, unsigned int black)
+{
+  unsigned int i, j, k, average, count;
+  unsigned int avg[3];
+  uint8_t val;
+
+  /* computes average value on black margin */
+  for (k = 0; k < channels; k++)
+    {
+      avg[k] = 0;
+      count = 0;
+      for (i = 0; i < lines; i++)
+	{
+	  for (j = 0; j < black; j++)
+	    {
+	      val = data[i * channels * pixels + j + k];
+	      avg[k] += val;
+	      count++;
+	    }
+	}
+      if (count)
+	avg[k] /= count;
+      DBG(DBG_info, "%s: avg[%d] = %d\n", __func__, k, avg[k]);
+    }
+  average = 0;
+  for (i = 0; i < channels; i++)
+    average += avg[i];
+  average /= channels;
+  DBG(DBG_info, "%s: average = %d\n", __func__, average);
+  return average;
+}
+
+
+void CommandSetGl124::offset_calibration(Genesys_Device* dev, const Genesys_Sensor& sensor,
+                                         Genesys_Register_Set& regs) const
+{
+    DBG_HELPER(dbg);
+    unsigned channels;
+  int pass = 0, avg, total_size;
+    int topavg, bottomavg, lines;
+  int top, bottom, black_pixels, pixels;
+
+    // no gain nor offset for TI AFE
+    uint8_t reg0a = dev->interface->read_register(REG_0x0A);
+    if (((reg0a & REG_0x0A_SIFSEL) >> REG_0x0AS_SIFSEL) == 3) {
+      return;
+    }
+
+  /* offset calibration is always done in color mode */
+  channels = 3;
+  dev->calib_pixels = sensor.sensor_pixels;
+  lines=1;
+    pixels = (sensor.sensor_pixels * sensor.optical_res) / sensor.optical_res;
+    black_pixels = (sensor.black_pixels * sensor.optical_res) / sensor.optical_res;
+  DBG(DBG_io2, "%s: black_pixels=%d\n", __func__, black_pixels);
+
+    ScanSession session;
+    session.params.xres = sensor.optical_res;
+    session.params.yres = sensor.optical_res;
+    session.params.startx = 0;
+    session.params.starty = 0;
+    session.params.pixels = pixels;
+    session.params.lines = lines;
+    session.params.depth = 8;
+    session.params.channels = channels;
+    session.params.scan_method = dev->settings.scan_method;
+    session.params.scan_mode = ScanColorMode::COLOR_SINGLE_PASS;
+    session.params.color_filter = dev->settings.color_filter;
+    session.params.flags = ScanFlag::DISABLE_SHADING |
+                           ScanFlag::DISABLE_GAMMA |
+                           ScanFlag::SINGLE_LINE |
+                           ScanFlag::IGNORE_LINE_DISTANCE;
+    compute_session(dev, session, sensor);
+
+    init_regs_for_scan_session(dev, sensor, &regs, session);
+
+  sanei_genesys_set_motor_power(regs, false);
+
+  /* allocate memory for scans */
+    total_size = pixels * channels * lines * (session.params.depth / 8);
+
+  std::vector<uint8_t> first_line(total_size);
+  std::vector<uint8_t> second_line(total_size);
+
+  /* init gain */
+  dev->frontend.set_gain(0, 0);
+  dev->frontend.set_gain(1, 0);
+  dev->frontend.set_gain(2, 0);
+
+  /* scan with no move */
+  bottom = 10;
+  dev->frontend.set_offset(0, bottom);
+  dev->frontend.set_offset(1, bottom);
+  dev->frontend.set_offset(2, bottom);
+
+    set_fe(dev, sensor, AFE_SET);
+    dev->interface->write_registers(regs);
+  DBG(DBG_info, "%s: starting first line reading\n", __func__);
+    begin_scan(dev, sensor, &regs, true);
+
+    if (is_testing_mode()) {
+        dev->interface->test_checkpoint("offset_calibration");
+        return;
+    }
+
+    sanei_genesys_read_data_from_scanner(dev, first_line.data(), total_size);
+  if (DBG_LEVEL >= DBG_data)
+   {
+      char title[30];
+        std::snprintf(title, 30, "gl124_offset%03d.pnm", bottom);
+        sanei_genesys_write_pnm_file(title, first_line.data(), session.params.depth,
+                                     channels, pixels, lines);
+   }
+
+  bottomavg = dark_average(first_line.data(), pixels, lines, channels, black_pixels);
+  DBG(DBG_io2, "%s: bottom avg=%d\n", __func__, bottomavg);
+
+  /* now top value */
+  top = 255;
+  dev->frontend.set_offset(0, top);
+  dev->frontend.set_offset(1, top);
+  dev->frontend.set_offset(2, top);
+    set_fe(dev, sensor, AFE_SET);
+    dev->interface->write_registers(regs);
+  DBG(DBG_info, "%s: starting second line reading\n", __func__);
+    begin_scan(dev, sensor, &regs, true);
+    sanei_genesys_read_data_from_scanner(dev, second_line.data(), total_size);
+
+  topavg = dark_average(second_line.data(), pixels, lines, channels, black_pixels);
+  DBG(DBG_io2, "%s: top avg=%d\n", __func__, topavg);
+
+  /* loop until acceptable level */
+  while ((pass < 32) && (top - bottom > 1))
+    {
+      pass++;
+
+      /* settings for new scan */
+      dev->frontend.set_offset(0, (top + bottom) / 2);
+      dev->frontend.set_offset(1, (top + bottom) / 2);
+      dev->frontend.set_offset(2, (top + bottom) / 2);
+
+        // scan with no move
+        set_fe(dev, sensor, AFE_SET);
+        dev->interface->write_registers(regs);
+      DBG(DBG_info, "%s: starting second line reading\n", __func__);
+        begin_scan(dev, sensor, &regs, true);
+        sanei_genesys_read_data_from_scanner(dev, second_line.data(), total_size);
+
+      if (DBG_LEVEL >= DBG_data)
+	{
+          char title[30];
+          std::snprintf(title, 30, "gl124_offset%03d.pnm", dev->frontend.get_offset(1));
+          sanei_genesys_write_pnm_file(title, second_line.data(), session.params.depth,
+                                       channels, pixels, lines);
+	}
+
+      avg = dark_average(second_line.data(), pixels, lines, channels, black_pixels);
+      DBG(DBG_info, "%s: avg=%d offset=%d\n", __func__, avg, dev->frontend.get_offset(1));
+
+      /* compute new boundaries */
+      if (topavg == avg)
+	{
+	  topavg = avg;
+          top = dev->frontend.get_offset(1);
+	}
+      else
+	{
+	  bottomavg = avg;
+          bottom = dev->frontend.get_offset(1);
+	}
+    }
+  DBG(DBG_info, "%s: offset=(%d,%d,%d)\n", __func__,
+      dev->frontend.get_offset(0),
+      dev->frontend.get_offset(1),
+      dev->frontend.get_offset(2));
+}
+
+
+/* alternative coarse gain calibration
+   this on uses the settings from offset_calibration and
+   uses only one scanline
+ */
+/*
+  with offset and coarse calibration we only want to get our input range into
+  a reasonable shape. the fine calibration of the upper and lower bounds will
+  be done with shading.
+ */
+void CommandSetGl124::coarse_gain_calibration(Genesys_Device* dev, const Genesys_Sensor& sensor,
+                                              Genesys_Register_Set& regs, int dpi) const
+{
+    DBG_HELPER_ARGS(dbg, "dpi = %d", dpi);
+  int pixels;
+  int total_size;
+  int i, j, channels;
+  int max[3];
+  float gain[3],coeff;
+  int val, code, lines;
+
+    // no gain nor offset for TI AFE
+    uint8_t reg0a = dev->interface->read_register(REG_0x0A);
+    if (((reg0a & REG_0x0A_SIFSEL) >> REG_0x0AS_SIFSEL) == 3) {
+      return;
+    }
+
+  /* coarse gain calibration is always done in color mode */
+  channels = 3;
+
+  if(dev->settings.xres<sensor.optical_res)
+    {
+        coeff = 0.9f;
+    } else {
+        coeff = 1.0f;
+    }
+  lines=10;
+     pixels = (sensor.sensor_pixels * sensor.optical_res) / sensor.optical_res;
+
+    ScanSession session;
+    session.params.xres = sensor.optical_res;
+    session.params.yres = sensor.optical_res;
+    session.params.startx = 0;
+    session.params.starty = 0;
+    session.params.pixels = pixels;
+    session.params.lines = lines;
+    session.params.depth = 8;
+    session.params.channels = channels;
+    session.params.scan_method = dev->settings.scan_method;
+    session.params.scan_mode = ScanColorMode::COLOR_SINGLE_PASS;
+    session.params.color_filter = dev->settings.color_filter;
+    session.params.flags = ScanFlag::DISABLE_SHADING |
+                           ScanFlag::DISABLE_GAMMA |
+                           ScanFlag::SINGLE_LINE |
+                           ScanFlag::IGNORE_LINE_DISTANCE;
+    compute_session(dev, session, sensor);
+
+    try {
+        init_regs_for_scan_session(dev, sensor, &regs, session);
+    } catch (...) {
+        catch_all_exceptions(__func__, [&](){ sanei_genesys_set_motor_power(regs, false); });
+        throw;
+    }
+
+    sanei_genesys_set_motor_power(regs, false);
+
+    dev->interface->write_registers(regs);
+
+    total_size = pixels * channels * (16 / session.params.depth) * lines;
+
+  std::vector<uint8_t> line(total_size);
+
+    set_fe(dev, sensor, AFE_SET);
+    begin_scan(dev, sensor, &regs, true);
+
+    if (is_testing_mode()) {
+        dev->interface->test_checkpoint("coarse_gain_calibration");
+        scanner_stop_action(*dev);
+        move_back_home(dev, true);
+        return;
+    }
+
+    sanei_genesys_read_data_from_scanner(dev, line.data(), total_size);
+
+    if (DBG_LEVEL >= DBG_data) {
+        sanei_genesys_write_pnm_file("gl124_gain.pnm", line.data(), session.params.depth,
+                                     channels, pixels, lines);
+    }
+
+  /* average value on each channel */
+  for (j = 0; j < channels; j++)
+    {
+      max[j] = 0;
+      for (i = pixels/4; i < (pixels*3/4); i++)
+	{
+            if (dev->model->is_cis) {
+                val = line[i + j * pixels];
+            } else {
+                val = line[i * channels + j];
+            }
+
+	    max[j] += val;
+	}
+      max[j] = max[j] / (pixels/2);
+
+      gain[j] = (static_cast<float>(sensor.gain_white_ref) * coeff) / max[j];
+
+      /* turn logical gain value into gain code, checking for overflow */
+        code = static_cast<int>(283 - 208 / gain[j]);
+      if (code > 255)
+	code = 255;
+      else if (code < 0)
+	code = 0;
+      dev->frontend.set_gain(j, code);
+
+      DBG(DBG_proc, "%s: channel %d, max=%d, gain = %f, setting:%d\n", __func__, j, max[j],
+          gain[j], dev->frontend.get_gain(j));
+    }
+
+    if (dev->model->is_cis) {
+        uint8_t gain0 = dev->frontend.get_gain(0);
+        if (gain0 > dev->frontend.get_gain(1)) {
+            gain0 = dev->frontend.get_gain(1);
+        }
+        if (gain0 > dev->frontend.get_gain(2)) {
+            gain0 = dev->frontend.get_gain(2);
+        }
+        dev->frontend.set_gain(0, gain0);
+        dev->frontend.set_gain(1, gain0);
+        dev->frontend.set_gain(2, gain0);
+    }
+
+    if (channels == 1) {
+        dev->frontend.set_gain(0, dev->frontend.get_gain(1));
+        dev->frontend.set_gain(2, dev->frontend.get_gain(1));
+    }
+
+    scanner_stop_action(*dev);
+
+    move_back_home(dev, true);
+}
+
+// wait for lamp warmup by scanning the same line until difference
+// between 2 scans is below a threshold
+void CommandSetGl124::init_regs_for_warmup(Genesys_Device* dev, const Genesys_Sensor& sensor,
+                                           Genesys_Register_Set* reg, int* channels,
+                                           int* total_size) const
+{
+    DBG_HELPER(dbg);
+  int num_pixels;
+
+  *channels=3;
+
+  *reg = dev->reg;
+
+    ScanSession session;
+    session.params.xres = sensor.optical_res;
+    session.params.yres = dev->motor.base_ydpi;
+    session.params.startx = sensor.sensor_pixels / 4;
+    session.params.starty = 0;
+    session.params.pixels = sensor.sensor_pixels / 2;
+    session.params.lines = 1;
+    session.params.depth = 8;
+    session.params.channels = *channels;
+    session.params.scan_method = dev->settings.scan_method;
+    session.params.scan_mode = ScanColorMode::COLOR_SINGLE_PASS;
+    session.params.color_filter = dev->settings.color_filter;
+    session.params.flags = ScanFlag::DISABLE_SHADING |
+                           ScanFlag::DISABLE_GAMMA |
+                           ScanFlag::SINGLE_LINE |
+                           ScanFlag::IGNORE_LINE_DISTANCE;
+    compute_session(dev, session, sensor);
+
+    init_regs_for_scan_session(dev, sensor, reg, session);
+
+    num_pixels = session.output_pixels;
+
+  *total_size = num_pixels * 3 * 1;        /* colors * bytes_per_color * scan lines */
+
+  sanei_genesys_set_motor_power(*reg, false);
+    dev->interface->write_registers(*reg);
+}
+
+/** @brief default GPIO values
+ * set up GPIO/GPOE for idle state
+ * @param dev device to set up
+ */
+static void gl124_init_gpio(Genesys_Device* dev)
+{
+    DBG_HELPER(dbg);
+  int idx;
+
+  /* per model GPIO layout */
+    if (dev->model->model_id == ModelId::CANON_LIDE_110) {
+      idx = 0;
+    } else if (dev->model->model_id == ModelId::CANON_LIDE_120) {
+      idx = 2;
+    }
+  else
+    {                                /* canon LiDE 210 and 220 case */
+      idx = 1;
+    }
+
+    dev->interface->write_register(REG_0x31, gpios[idx].r31);
+    dev->interface->write_register(REG_0x32, gpios[idx].r32);
+    dev->interface->write_register(REG_0x33, gpios[idx].r33);
+    dev->interface->write_register(REG_0x34, gpios[idx].r34);
+    dev->interface->write_register(REG_0x35, gpios[idx].r35);
+    dev->interface->write_register(REG_0x36, gpios[idx].r36);
+    dev->interface->write_register(REG_0x38, gpios[idx].r38);
+}
+
+/**
+ * set memory layout by filling values in dedicated registers
+ */
+static void gl124_init_memory_layout(Genesys_Device* dev)
+{
+    DBG_HELPER(dbg);
+  int idx = 0;
+
+  /* point to per model memory layout */
+    if (dev->model->model_id == ModelId::CANON_LIDE_110 ||
+        dev->model->model_id == ModelId::CANON_LIDE_120)
+    {
+      idx = 0;
+    }
+  else
+    {                                /* canon LiDE 210 and 220 case */
+      idx = 1;
+    }
+
+  /* setup base address for shading data. */
+  /* values must be multiplied by 8192=0x4000 to give address on AHB */
+  /* R-Channel shading bank0 address setting for CIS */
+    dev->interface->write_register(0xd0, layouts[idx].rd0);
+  /* G-Channel shading bank0 address setting for CIS */
+    dev->interface->write_register(0xd1, layouts[idx].rd1);
+  /* B-Channel shading bank0 address setting for CIS */
+    dev->interface->write_register(0xd2, layouts[idx].rd2);
+
+  /* setup base address for scanned data. */
+  /* values must be multiplied by 1024*2=0x0800 to give address on AHB */
+  /* R-Channel ODD image buffer 0x0124->0x92000 */
+  /* size for each buffer is 0x16d*1k word */
+    dev->interface->write_register(0xe0, layouts[idx].re0);
+    dev->interface->write_register(0xe1, layouts[idx].re1);
+  /* R-Channel ODD image buffer end-address 0x0291->0x148800 => size=0xB6800*/
+    dev->interface->write_register(0xe2, layouts[idx].re2);
+    dev->interface->write_register(0xe3, layouts[idx].re3);
+
+  /* R-Channel EVEN image buffer 0x0292 */
+    dev->interface->write_register(0xe4, layouts[idx].re4);
+    dev->interface->write_register(0xe5, layouts[idx].re5);
+  /* R-Channel EVEN image buffer end-address 0x03ff*/
+    dev->interface->write_register(0xe6, layouts[idx].re6);
+    dev->interface->write_register(0xe7, layouts[idx].re7);
+
+  /* same for green, since CIS, same addresses */
+    dev->interface->write_register(0xe8, layouts[idx].re0);
+    dev->interface->write_register(0xe9, layouts[idx].re1);
+    dev->interface->write_register(0xea, layouts[idx].re2);
+    dev->interface->write_register(0xeb, layouts[idx].re3);
+    dev->interface->write_register(0xec, layouts[idx].re4);
+    dev->interface->write_register(0xed, layouts[idx].re5);
+    dev->interface->write_register(0xee, layouts[idx].re6);
+    dev->interface->write_register(0xef, layouts[idx].re7);
+
+/* same for blue, since CIS, same addresses */
+    dev->interface->write_register(0xf0, layouts[idx].re0);
+    dev->interface->write_register(0xf1, layouts[idx].re1);
+    dev->interface->write_register(0xf2, layouts[idx].re2);
+    dev->interface->write_register(0xf3, layouts[idx].re3);
+    dev->interface->write_register(0xf4, layouts[idx].re4);
+    dev->interface->write_register(0xf5, layouts[idx].re5);
+    dev->interface->write_register(0xf6, layouts[idx].re6);
+    dev->interface->write_register(0xf7, layouts[idx].re7);
+}
+
+/**
+ * initialize backend and ASIC : registers, motor tables, and gamma tables
+ * then ensure scanner's head is at home
+ */
+void CommandSetGl124::init(Genesys_Device* dev) const
+{
+  DBG_INIT ();
+    DBG_HELPER(dbg);
+
+    sanei_genesys_asic_init(dev, 0);
+}
+
+
+/* *
+ * initialize ASIC from power on condition
+ */
+void CommandSetGl124::asic_boot(Genesys_Device* dev, bool cold) const
+{
+    DBG_HELPER(dbg);
+
+    // reset ASIC in case of cold boot
+    if (cold) {
+        dev->interface->write_register(0x0e, 0x01);
+        dev->interface->write_register(0x0e, 0x00);
+    }
+
+    // enable GPOE 17
+    dev->interface->write_register(0x36, 0x01);
+
+    // set GPIO 17
+    uint8_t val = dev->interface->read_register(0x33);
+    val |= 0x01;
+    dev->interface->write_register(0x33, val);
+
+    // test CHKVER
+    val = dev->interface->read_register(REG_0x100);
+    if (val & REG_0x100_CHKVER) {
+        val = dev->interface->read_register(0x00);
+        DBG(DBG_info, "%s: reported version for genesys chip is 0x%02x\n", __func__, val);
+    }
+
+  /* Set default values for registers */
+  gl124_init_registers (dev);
+
+    // Write initial registers
+    dev->interface->write_registers(dev->reg);
+
+    // tune reg 0B
+    dev->interface->write_register(REG_0x0B, REG_0x0B_30MHZ | REG_0x0B_ENBDRAM | REG_0x0B_64M);
+  dev->reg.remove_reg(0x0b);
+
+    //set up end access
+    dev->interface->write_0x8c(0x10, 0x0b);
+    dev->interface->write_0x8c(0x13, 0x0e);
+
+  /* CIS_LINE */
+    dev->reg.init_reg(0x08, REG_0x08_CIS_LINE);
+    dev->interface->write_register(0x08, dev->reg.find_reg(0x08).value);
+
+    // setup gpio
+    gl124_init_gpio(dev);
+
+    // setup internal memory layout
+    gl124_init_memory_layout(dev);
+}
+
+
+void CommandSetGl124::update_hardware_sensors(Genesys_Scanner* s) const
+{
+  /* do what is needed to get a new set of events, but try to not loose
+     any of them.
+   */
+    DBG_HELPER(dbg);
+    uint8_t val = s->dev->interface->read_register(REG_0x31);
+
+  /* TODO : for the next scanner special case,
+   * add another per scanner button profile struct to avoid growing
+   * hard-coded button mapping here.
+   */
+    if ((s->dev->model->gpio_id == GpioId::CANON_LIDE_110) ||
+        (s->dev->model->gpio_id == GpioId::CANON_LIDE_120))
+    {
+        s->buttons[BUTTON_SCAN_SW].write((val & 0x01) == 0);
+        s->buttons[BUTTON_FILE_SW].write((val & 0x08) == 0);
+        s->buttons[BUTTON_EMAIL_SW].write((val & 0x04) == 0);
+        s->buttons[BUTTON_COPY_SW].write((val & 0x02) == 0);
+    }
+  else
+    { /* LiDE 210 case */
+        s->buttons[BUTTON_EXTRA_SW].write((val & 0x01) == 0);
+        s->buttons[BUTTON_SCAN_SW].write((val & 0x02) == 0);
+        s->buttons[BUTTON_COPY_SW].write((val & 0x04) == 0);
+        s->buttons[BUTTON_EMAIL_SW].write((val & 0x08) == 0);
+        s->buttons[BUTTON_FILE_SW].write((val & 0x10) == 0);
+    }
+}
+
+void CommandSetGl124::update_home_sensor_gpio(Genesys_Device& dev) const
+{
+    DBG_HELPER(dbg);
+
+    std::uint8_t val = dev.interface->read_register(REG_0x32);
+    val &= ~REG_0x32_GPIO10;
+    dev.interface->write_register(REG_0x32, val);
+}
+
+bool CommandSetGl124::needs_home_before_init_regs_for_scan(Genesys_Device* dev) const
+{
+    (void) dev;
+    return true;
+}
+
+void CommandSetGl124::send_gamma_table(Genesys_Device* dev, const Genesys_Sensor& sensor) const
+{
+    sanei_genesys_send_gamma_table(dev, sensor);
+}
+
+void CommandSetGl124::load_document(Genesys_Device* dev) const
+{
+    (void) dev;
+    throw SaneException("not implemented");
+}
+
+void CommandSetGl124::detect_document_end(Genesys_Device* dev) const
+{
+    (void) dev;
+    throw SaneException("not implemented");
+}
+
+void CommandSetGl124::eject_document(Genesys_Device* dev) const
+{
+    (void) dev;
+    throw SaneException("not implemented");
+}
+
+void CommandSetGl124::search_strip(Genesys_Device* dev, const Genesys_Sensor& sensor,
+                                   bool forward, bool black) const
+{
+    (void) dev;
+    (void) sensor;
+    (void) forward;
+    (void) black;
+    throw SaneException("not implemented");
+}
+
+void CommandSetGl124::move_to_ta(Genesys_Device* dev) const
+{
+    (void) dev;
+    throw SaneException("not implemented");
+}
+
+std::unique_ptr<CommandSet> create_gl124_cmd_set()
+{
+    return std::unique_ptr<CommandSet>(new CommandSetGl124{});
+}
+
+} // namespace gl124
+} // namespace genesys