diff --git a/backend/genesys/command_set.h b/backend/genesys/command_set.h
index eed6fce8e..0de798171 100644
--- a/backend/genesys/command_set.h
+++ b/backend/genesys/command_set.h
@@ -76,8 +76,6 @@ 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_gain4_bit(Genesys_Register_Set * reg) const = 0;
-
     virtual bool test_buffer_empty_bit(std::uint8_t val) const = 0;
 
     virtual void set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, std::uint8_t set) const = 0;
diff --git a/backend/genesys/genesys.cpp b/backend/genesys/genesys.cpp
index 3634ca033..e4f73b46c 100644
--- a/backend/genesys/genesys.cpp
+++ b/backend/genesys/genesys.cpp
@@ -2094,7 +2094,7 @@ static void genesys_send_shading_coefficient(Genesys_Device* dev, const Genesys_
      Wn = white average for column n
      Dn = dark average for column n
    */
-    if (dev->cmd_set->get_gain4_bit(&dev->calib_reg)) {
+    if (get_registers_gain4_bit(dev->model->asic_type, dev->calib_reg)) {
         coeff = 0x4000;
     } else {
         coeff = 0x2000;
diff --git a/backend/genesys/gl124.cpp b/backend/genesys/gl124.cpp
index 44b10c118..69376ebb6 100644
--- a/backend/genesys/gl124.cpp
+++ b/backend/genesys/gl124.cpp
@@ -53,11 +53,6 @@
 namespace genesys {
 namespace gl124 {
 
-bool CommandSetGl124::get_gain4_bit(Genesys_Register_Set* regs) const
-{
-    return static_cast<bool>(regs->get8(REG_0x06) & REG_0x06_GAIN4);
-}
-
 bool CommandSetGl124::test_buffer_empty_bit(SANE_Byte val) const
 {
     return (val & BUFEMPTY);
diff --git a/backend/genesys/gl124.h b/backend/genesys/gl124.h
index e8a8caf03..5dbeb27c6 100644
--- a/backend/genesys/gl124.h
+++ b/backend/genesys/gl124.h
@@ -137,8 +137,6 @@ public:
 
     void init_regs_for_scan(Genesys_Device* dev, const Genesys_Sensor& sensor) const override;
 
-    bool get_gain4_bit(Genesys_Register_Set * reg) const override;
-
     bool test_buffer_empty_bit(std::uint8_t val) const override;
 
     void set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, uint8_t set) const override;
diff --git a/backend/genesys/gl646.cpp b/backend/genesys/gl646.cpp
index 042fc3f89..0706d8a72 100644
--- a/backend/genesys/gl646.cpp
+++ b/backend/genesys/gl646.cpp
@@ -90,12 +90,6 @@ static void gl646_gpio_output_enable(IUsbDevice& usb_dev, uint8_t value)
     usb_dev.control_msg(REQUEST_TYPE_OUT, REQUEST_REGISTER, GPIO_OUTPUT_ENABLE, INDEX, 1, &value);
 }
 
-bool CommandSetGl646::get_gain4_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, 0x06);
-    return (r && (r->value & REG_0x06_GAIN4));
-}
-
 bool CommandSetGl646::test_buffer_empty_bit(SANE_Byte val) const
 {
     return (val & REG_0x41_BUFEMPTY);
diff --git a/backend/genesys/gl646.h b/backend/genesys/gl646.h
index 910f0e49b..21c8ce31e 100644
--- a/backend/genesys/gl646.h
+++ b/backend/genesys/gl646.h
@@ -254,8 +254,6 @@ public:
 
     void init_regs_for_scan(Genesys_Device* dev, const Genesys_Sensor& sensor) const override;
 
-    bool get_gain4_bit(Genesys_Register_Set * reg) const override;
-
     bool test_buffer_empty_bit(std::uint8_t val) const override;
 
     void set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, uint8_t set) const override;
diff --git a/backend/genesys/gl646_registers.h b/backend/genesys/gl646_registers.h
index 76ed24dc6..06dafae29 100644
--- a/backend/genesys/gl646_registers.h
+++ b/backend/genesys/gl646_registers.h
@@ -98,6 +98,7 @@ static constexpr RegMask REG_0x05_GMMENB = 0x08;
 static constexpr RegMask REG_0x05_LEDADD = 0x04;
 static constexpr RegMask REG_0x05_BASESEL = 0x03;
 
+static constexpr RegAddr REG_0x06 = 0x06;
 static constexpr RegMask REG_0x06_PWRBIT = 0x10;
 static constexpr RegMask REG_0x06_GAIN4 = 0x08;
 static constexpr RegMask REG_0x06_OPTEST = 0x07;
diff --git a/backend/genesys/gl841.cpp b/backend/genesys/gl841.cpp
index e5e94bf7e..cdce82b8c 100644
--- a/backend/genesys/gl841.cpp
+++ b/backend/genesys/gl841.cpp
@@ -68,12 +68,6 @@ static int gl841_exposure_time(Genesys_Device *dev, const Genesys_Sensor& sensor
                                int start,
                                int used_pixels);
 
-bool CommandSetGl841::get_gain4_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, 0x06);
-    return (r && (r->value & REG_0x06_GAIN4));
-}
-
 bool CommandSetGl841::test_buffer_empty_bit(SANE_Byte val) const
 {
     return (val & REG_0x41_BUFEMPTY);
diff --git a/backend/genesys/gl841.h b/backend/genesys/gl841.h
index 2b91c05fd..292be20c9 100644
--- a/backend/genesys/gl841.h
+++ b/backend/genesys/gl841.h
@@ -71,8 +71,6 @@ public:
 
     void init_regs_for_scan(Genesys_Device* dev, const Genesys_Sensor& sensor) const override;
 
-    bool get_gain4_bit(Genesys_Register_Set* reg) const override;
-
     bool test_buffer_empty_bit(std::uint8_t val) const override;
 
     void set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, uint8_t set) const override;
diff --git a/backend/genesys/gl841_registers.h b/backend/genesys/gl841_registers.h
index 0e45db644..e8f8a14fa 100644
--- a/backend/genesys/gl841_registers.h
+++ b/backend/genesys/gl841_registers.h
@@ -95,6 +95,7 @@ static constexpr RegMask REG_0x05_MTLLAMP = 0x30;
 static constexpr RegMask REG_0x05_GMMENB = 0x08;
 static constexpr RegMask REG_0x05_MTLBASE = 0x03;
 
+static constexpr RegAddr REG_0x06 = 0x06;
 static constexpr RegMask REG_0x06_SCANMOD = 0xe0;
 static constexpr RegShift REG_0x06S_SCANMOD = 5;
 static constexpr RegMask REG_0x06_PWRBIT = 0x10;
diff --git a/backend/genesys/gl843.cpp b/backend/genesys/gl843.cpp
index df4263258..080252345 100644
--- a/backend/genesys/gl843.cpp
+++ b/backend/genesys/gl843.cpp
@@ -63,12 +63,6 @@ static void gl843_set_buffer_address(Genesys_Device* dev, uint32_t addr)
     dev->interface->write_register(0x5c, (addr & 0xff));
 }
 
-bool CommandSetGl843::get_gain4_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, REG_0x06);
-    return (r && (r->value & REG_0x06_GAIN4));
-}
-
 /**
  * compute the step multiplier used
  */
diff --git a/backend/genesys/gl843.h b/backend/genesys/gl843.h
index 9cb4648f8..b3b87eec8 100644
--- a/backend/genesys/gl843.h
+++ b/backend/genesys/gl843.h
@@ -71,8 +71,6 @@ public:
 
     void init_regs_for_scan(Genesys_Device* dev, const Genesys_Sensor& sensor) const override;
 
-    bool get_gain4_bit(Genesys_Register_Set * reg) const override;
-
     bool test_buffer_empty_bit(std::uint8_t val) const override;
 
     void set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, uint8_t set) const override;
diff --git a/backend/genesys/gl846.cpp b/backend/genesys/gl846.cpp
index 586de6237..1ca81e3a4 100644
--- a/backend/genesys/gl846.cpp
+++ b/backend/genesys/gl846.cpp
@@ -58,12 +58,6 @@
 namespace genesys {
 namespace gl846 {
 
-bool CommandSetGl846::get_gain4_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, 0x06);
-    return (r && (r->value & REG_0x06_GAIN4));
-}
-
 bool CommandSetGl846::test_buffer_empty_bit(SANE_Byte val) const
 {
     return (val & REG_0x41_BUFEMPTY);
diff --git a/backend/genesys/gl846.h b/backend/genesys/gl846.h
index d5d67c193..66ac5f2d8 100644
--- a/backend/genesys/gl846.h
+++ b/backend/genesys/gl846.h
@@ -156,8 +156,6 @@ public:
 
     void init_regs_for_scan(Genesys_Device* dev, const Genesys_Sensor& sensor) const override;
 
-    bool get_gain4_bit(Genesys_Register_Set * reg) const override;
-
     bool test_buffer_empty_bit(std::uint8_t val) const override;
 
     void set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, uint8_t set) const override;
diff --git a/backend/genesys/gl846_registers.h b/backend/genesys/gl846_registers.h
index fc796c731..39b302921 100644
--- a/backend/genesys/gl846_registers.h
+++ b/backend/genesys/gl846_registers.h
@@ -99,6 +99,7 @@ static constexpr RegMask REG_0x05_MTLLAMP = 0x30;
 static constexpr RegMask REG_0x05_GMMENB = 0x08;
 static constexpr RegMask REG_0x05_MTLBASE = 0x03;
 
+static constexpr RegAddr REG_0x06 = 0x06;
 static constexpr RegMask REG_0x06_SCANMOD = 0xe0;
 static constexpr RegShift REG_0x06S_SCANMOD = 5;
 static constexpr RegMask REG_0x06_PWRBIT = 0x10;
diff --git a/backend/genesys/gl847.cpp b/backend/genesys/gl847.cpp
index 2b060d7f6..bed5c8303 100644
--- a/backend/genesys/gl847.cpp
+++ b/backend/genesys/gl847.cpp
@@ -53,12 +53,6 @@
 namespace genesys {
 namespace gl847 {
 
-bool CommandSetGl847::get_gain4_bit(Genesys_Register_Set* regs) const
-{
-    GenesysRegister *r = sanei_genesys_get_address(regs, 0x06);
-    return (r && (r->value & REG_0x06_GAIN4));
-}
-
 bool CommandSetGl847::test_buffer_empty_bit(SANE_Byte val) const
 {
     return (val & REG_0x41_BUFEMPTY);
diff --git a/backend/genesys/gl847.h b/backend/genesys/gl847.h
index 4b79384a5..fce01ade1 100644
--- a/backend/genesys/gl847.h
+++ b/backend/genesys/gl847.h
@@ -140,8 +140,6 @@ public:
 
     void init_regs_for_scan(Genesys_Device* dev, const Genesys_Sensor& sensor) const override;
 
-    bool get_gain4_bit(Genesys_Register_Set * reg) const override;
-
     bool test_buffer_empty_bit(std::uint8_t val) const override;
 
     void set_fe(Genesys_Device* dev, const Genesys_Sensor& sensor, uint8_t set) const override;
diff --git a/backend/genesys/gl847_registers.h b/backend/genesys/gl847_registers.h
index 47f399323..0603a6a65 100644
--- a/backend/genesys/gl847_registers.h
+++ b/backend/genesys/gl847_registers.h
@@ -98,6 +98,7 @@ static constexpr RegMask REG_0x05_MTLLAMP = 0x30;
 static constexpr RegMask REG_0x05_GMMENB = 0x08;
 static constexpr RegMask REG_0x05_MTLBASE = 0x03;
 
+static constexpr RegAddr REG_0x06 = 0x06;
 static constexpr RegMask REG_0x06_SCANMOD = 0xe0;
 static constexpr RegMask REG_0x06S_SCANMOD = 5;
 static constexpr RegMask REG_0x06_PWRBIT = 0x10;
diff --git a/backend/genesys/low.cpp b/backend/genesys/low.cpp
index 53ef44cd6..cda1b7051 100644
--- a/backend/genesys/low.cpp
+++ b/backend/genesys/low.cpp
@@ -48,6 +48,13 @@
 #include "assert.h"
 #include "test_settings.h"
 
+#include "gl124_registers.h"
+#include "gl841_registers.h"
+#include "gl843_registers.h"
+#include "gl846_registers.h"
+#include "gl847_registers.h"
+#include "gl646_registers.h"
+
 #include <cstdio>
 #include <cmath>
 #include <vector>
@@ -1600,6 +1607,27 @@ void sanei_genesys_set_dpihw(Genesys_Register_Set& regs, const Genesys_Sensor& s
     regs.set8_mask(0x05, dpihw_setting, REG_0x05_DPIHW_MASK);
 }
 
+bool get_registers_gain4_bit(AsicType asic_type, const Genesys_Register_Set& regs)
+{
+    switch (asic_type) {
+        case AsicType::GL646:
+            return static_cast<bool>(regs.get8(gl646::REG_0x06) & gl646::REG_0x06_GAIN4);
+        case AsicType::GL841:
+            return static_cast<bool>(regs.get8(gl841::REG_0x06) & gl841::REG_0x06_GAIN4);
+        case AsicType::GL843:
+            return static_cast<bool>(regs.get8(gl843::REG_0x06) & gl843::REG_0x06_GAIN4);
+        case AsicType::GL845:
+        case AsicType::GL846:
+            return static_cast<bool>(regs.get8(gl846::REG_0x06) & gl846::REG_0x06_GAIN4);
+        case AsicType::GL847:
+            return static_cast<bool>(regs.get8(gl847::REG_0x06) & gl847::REG_0x06_GAIN4);
+        case AsicType::GL124:
+            return static_cast<bool>(regs.get8(gl124::REG_0x06) & gl124::REG_0x06_GAIN4);
+        default:
+            throw SaneException("Unsupported chipset");
+    }
+}
+
 /**
  * Wait for the scanning head to park
  */
diff --git a/backend/genesys/low.h b/backend/genesys/low.h
index b8247c6e2..49f720127 100644
--- a/backend/genesys/low.h
+++ b/backend/genesys/low.h
@@ -402,6 +402,8 @@ inline SensorExposure sanei_genesys_fixup_exposure(SensorExposure exposure)
     return exposure;
 }
 
+bool get_registers_gain4_bit(AsicType asic_type, const Genesys_Register_Set& regs);
+
 extern void sanei_genesys_wait_for_home(Genesys_Device* dev);
 
 extern void sanei_genesys_asic_init(Genesys_Device* dev, bool cold);