Update upstream source from tag 'upstream/1.0.31'

Update to upstream version '1.0.31'
with Debian dir aa7a39fe56343f5e164eec83783f4c923a394865

1 files changed, 607 insertions, 627 deletions

diff --git a/backend/genesys/low.cpp b/backend/genesys/low.cpp
index 7937fcc..05ef46b 100644
--- a/backend/genesys/low.cpp
+++ b/backend/genesys/low.cpp
@@ -51,12 +51,23 @@
 #include "gl124_registers.h"
 #include "gl646_registers.h"
 #include "gl841_registers.h"
+#include "gl842_registers.h"
 #include "gl843_registers.h"
 #include "gl846_registers.h"
 #include "gl847_registers.h"
 #include "gl646_registers.h"
 
+#include "gl124.h"
+#include "gl646.h"
+#include "gl841.h"
+#include "gl842.h"
+#include "gl843.h"
+#include "gl846.h"
+#include "gl847.h"
+#include "gl646.h"
+
 #include <cstdio>
+#include <chrono>
 #include <cmath>
 #include <vector>
 
@@ -66,29 +77,17 @@
 
 namespace genesys {
 
-/**
- * setup the hardware dependent functions
- */
-
-namespace gl124 { std::unique_ptr<CommandSet> create_gl124_cmd_set(); }
-namespace gl646 { std::unique_ptr<CommandSet> create_gl646_cmd_set(); }
-namespace gl841 { std::unique_ptr<CommandSet> create_gl841_cmd_set(); }
-namespace gl843 { std::unique_ptr<CommandSet> create_gl843_cmd_set(); }
-namespace gl846 { std::unique_ptr<CommandSet> create_gl846_cmd_set(); }
-namespace gl847 { std::unique_ptr<CommandSet> create_gl847_cmd_set(); }
-
-void sanei_genesys_init_cmd_set(Genesys_Device* dev)
+std::unique_ptr<CommandSet> create_cmd_set(AsicType asic_type)
 {
-  DBG_INIT ();
-    DBG_HELPER(dbg);
-    switch (dev->model->asic_type) {
-        case AsicType::GL646: dev->cmd_set = gl646::create_gl646_cmd_set(); break;
-        case AsicType::GL841: dev->cmd_set = gl841::create_gl841_cmd_set(); break;
-        case AsicType::GL843: dev->cmd_set = gl843::create_gl843_cmd_set(); break;
+    switch (asic_type) {
+        case AsicType::GL646: return std::unique_ptr<CommandSet>(new gl646::CommandSetGl646{});
+        case AsicType::GL841: return std::unique_ptr<CommandSet>(new gl841::CommandSetGl841{});
+        case AsicType::GL842: return std::unique_ptr<CommandSet>(new gl842::CommandSetGl842{});
+        case AsicType::GL843: return std::unique_ptr<CommandSet>(new gl843::CommandSetGl843{});
         case AsicType::GL845: // since only a few reg bits differs we handle both together
-        case AsicType::GL846: dev->cmd_set = gl846::create_gl846_cmd_set(); break;
-        case AsicType::GL847: dev->cmd_set = gl847::create_gl847_cmd_set(); break;
-        case AsicType::GL124: dev->cmd_set = gl124::create_gl124_cmd_set(); break;
+        case AsicType::GL846: return std::unique_ptr<CommandSet>(new gl846::CommandSetGl846{});
+        case AsicType::GL847: return std::unique_ptr<CommandSet>(new gl847::CommandSetGl847{});
+        case AsicType::GL124: return std::unique_ptr<CommandSet>(new gl124::CommandSetGl124{});
         default: throw SaneException(SANE_STATUS_INVAL, "unknown ASIC type");
     }
 }
@@ -108,116 +107,6 @@ void sanei_genesys_write_file(const char* filename, const std::uint8_t* data, st
     std::fclose(out);
 }
 
-// Write data to a pnm file (e.g. calibration). For debugging only
-// data is RGB or grey, with little endian byte order
-void sanei_genesys_write_pnm_file(const char* filename, const std::uint8_t* data, int depth,
-                                  int channels, int pixels_per_line, int lines)
-{
-    DBG_HELPER_ARGS(dbg, "depth=%d, channels=%d, ppl=%d, lines=%d", depth, channels,
-                    pixels_per_line, lines);
-  int count;
-
-    std::FILE* out = std::fopen(filename, "w");
-  if (!out)
-    {
-        throw SaneException("could not open %s for writing: %s\n", filename, strerror(errno));
-    }
-  if(depth==1)
-    {
-      fprintf (out, "P4\n%d\n%d\n", pixels_per_line, lines);
-    }
-  else
-    {
-        std::fprintf(out, "P%c\n%d\n%d\n%d\n", channels == 1 ? '5' : '6', pixels_per_line, lines,
-                     static_cast<int>(std::pow(static_cast<double>(2),
-                                               static_cast<double>(depth - 1))));
-    }
-  if (channels == 3)
-    {
-      for (count = 0; count < (pixels_per_line * lines * 3); count++)
-	{
-	  if (depth == 16)
-	    fputc (*(data + 1), out);
-	  fputc (*(data++), out);
-	  if (depth == 16)
-	    data++;
-	}
-    }
-  else
-    {
-      if (depth==1)
-        {
-          pixels_per_line/=8;
-        }
-      for (count = 0; count < (pixels_per_line * lines); count++)
-	{
-          switch (depth)
-            {
-              case 8:
-	        fputc (*(data + count), out);
-                break;
-              case 16:
-	        fputc (*(data + 1), out);
-	        fputc (*(data), out);
-	        data += 2;
-                break;
-              default:
-                fputc(data[count], out);
-                break;
-            }
-	}
-    }
-    std::fclose(out);
-}
-
-void sanei_genesys_write_pnm_file16(const char* filename, const uint16_t* data, unsigned channels,
-                                    unsigned pixels_per_line, unsigned lines)
-{
-    DBG_HELPER_ARGS(dbg, "channels=%d, ppl=%d, lines=%d", channels,
-                    pixels_per_line, lines);
-
-    std::FILE* out = std::fopen(filename, "w");
-    if (!out) {
-        throw SaneException("could not open %s for writing: %s\n", filename, strerror(errno));
-    }
-    std::fprintf(out, "P%c\n%d\n%d\n%d\n", channels == 1 ? '5' : '6',
-                 pixels_per_line, lines, 256 * 256 - 1);
-
-    for (unsigned count = 0; count < (pixels_per_line * lines * channels); count++) {
-        fputc(*data >> 8, out);
-        fputc(*data & 0xff, out);
-        data++;
-    }
-    std::fclose(out);
-}
-
-bool is_supported_write_pnm_file_image_format(PixelFormat format)
-{
-    switch (format) {
-        case PixelFormat::I1:
-        case PixelFormat::RGB111:
-        case PixelFormat::I8:
-        case PixelFormat::RGB888:
-        case PixelFormat::I16:
-        case PixelFormat::RGB161616:
-            return true;
-        default:
-            return false;
-    }
-}
-
-void sanei_genesys_write_pnm_file(const char* filename, const Image& image)
-{
-    if (!is_supported_write_pnm_file_image_format(image.get_format())) {
-        throw SaneException("Unsupported format %d", static_cast<unsigned>(image.get_format()));
-    }
-
-    sanei_genesys_write_pnm_file(filename, image.get_row_ptr(0),
-                                 get_pixel_format_depth(image.get_format()),
-                                 get_pixel_channels(image.get_format()),
-                                 image.get_width(), image.get_height());
-}
-
 /* ------------------------------------------------------------------------ */
 /*                  Read and write RAM, registers and AFE                   */
 /* ------------------------------------------------------------------------ */
@@ -276,6 +165,7 @@ Status scanner_read_status(Genesys_Device& dev)
         case AsicType::GL124: address = 0x101; break;
         case AsicType::GL646:
         case AsicType::GL841:
+        case AsicType::GL842:
         case AsicType::GL843:
         case AsicType::GL845:
         case AsicType::GL846:
@@ -336,28 +226,23 @@ void debug_print_status(DebugMessageHelper& dbg, Status val)
     dbg.vlog(DBG_info, "status=%s\n", str.str().c_str());
 }
 
-#if 0
-/* returns pixels per line from register set */
-/*candidate for moving into chip specific files?*/
-static int
-genesys_pixels_per_line (Genesys_Register_Set * reg)
+void scanner_register_rw_clear_bits(Genesys_Device& dev, std::uint16_t address, std::uint8_t mask)
 {
-    int pixels_per_line;
-
-    pixels_per_line = reg->get8(0x32) * 256 + reg->get8(0x33);
-    pixels_per_line -= (reg->get8(0x30) * 256 + reg->get8(0x31));
+    scanner_register_rw_bits(dev, address, 0x00, mask);
+}
 
-    return pixels_per_line;
+void scanner_register_rw_set_bits(Genesys_Device& dev, std::uint16_t address, std::uint8_t mask)
+{
+    scanner_register_rw_bits(dev, address, mask, mask);
 }
 
-/* returns dpiset from register set */
-/*candidate for moving into chip specific files?*/
-static int
-genesys_dpiset (Genesys_Register_Set * reg)
+void scanner_register_rw_bits(Genesys_Device& dev, std::uint16_t address,
+                              std::uint8_t value, std::uint8_t mask)
 {
-    return reg->get8(0x2c) * 256 + reg->get8(0x2d);
+    auto reg_value = dev.interface->read_register(address);
+    reg_value = (reg_value & ~mask) | (value & mask);
+    dev.interface->write_register(address, reg_value);
 }
-#endif
 
 /** read the number of valid words in scanner's RAM
  * ie registers 42-43-44
@@ -481,7 +366,7 @@ void wait_until_has_valid_words(Genesys_Device* dev)
     unsigned words = 0;
     unsigned sleep_time_ms = 10;
 
-    for (unsigned wait_ms = 0; wait_ms < 50000; wait_ms += sleep_time_ms) {
+    for (unsigned wait_ms = 0; wait_ms < 70000; wait_ms += sleep_time_ms) {
         sanei_genesys_read_valid_words(dev, &words);
         if (words != 0)
             break;
@@ -516,7 +401,7 @@ Image read_unshuffled_image_from_scanner(Genesys_Device* dev, const ScanSession&
                                       dev->model->line_mode_color_order);
 
     auto width = get_pixels_from_row_bytes(format, session.output_line_bytes_raw);
-    auto height = session.output_line_count * (dev->model->is_cis ? session.params.channels : 1);
+    auto height = session.optical_line_count;
 
     Image image(width, height, format);
 
@@ -525,7 +410,7 @@ Image read_unshuffled_image_from_scanner(Genesys_Device* dev, const ScanSession&
         throw SaneException("Trying to read too much data %zu (max %zu)", total_bytes, max_bytes);
     }
     if (total_bytes != max_bytes) {
-        DBG(DBG_info, "WARNING %s: trying to read not enough data (%zu, full fill %zu\n", __func__,
+        DBG(DBG_info, "WARNING %s: trying to read not enough data (%zu, full fill %zu)\n", __func__,
             total_bytes, max_bytes);
     }
 
@@ -534,26 +419,138 @@ Image read_unshuffled_image_from_scanner(Genesys_Device* dev, const ScanSession&
     ImagePipelineStack pipeline;
     pipeline.push_first_node<ImagePipelineNodeImageSource>(image);
 
-    if ((dev->model->flags & GENESYS_FLAG_16BIT_DATA_INVERTED) && session.params.depth == 16) {
-        dev->pipeline.push_node<ImagePipelineNodeSwap16BitEndian>();
+    if (session.segment_count > 1) {
+        auto output_width = session.output_segment_pixel_group_count * session.segment_count;
+        pipeline.push_node<ImagePipelineNodeDesegment>(output_width, dev->segment_order,
+                                                       session.conseq_pixel_dist,
+                                                       1, 1);
     }
 
+    if (session.params.depth == 16) {
+        unsigned num_swaps = 0;
+        if (has_flag(dev->model->flags, ModelFlag::SWAP_16BIT_DATA)) {
+            num_swaps++;
+        }
 #ifdef WORDS_BIGENDIAN
-    if (depth == 16) {
-        dev->pipeline.push_node<ImagePipelineNodeSwap16BitEndian>();
+        num_swaps++;
+#endif
+        if (num_swaps % 2 != 0) {
+            dev->pipeline.push_node<ImagePipelineNodeSwap16BitEndian>();
+        }
     }
+
+    if (has_flag(dev->model->flags, ModelFlag::INVERT_PIXEL_DATA)) {
+        pipeline.push_node<ImagePipelineNodeInvert>();
+    }
+
+    if (dev->model->is_cis && session.params.channels == 3) {
+        pipeline.push_node<ImagePipelineNodeMergeMonoLines>(dev->model->line_mode_color_order);
+    }
+
+    if (pipeline.get_output_format() == PixelFormat::BGR888) {
+        pipeline.push_node<ImagePipelineNodeFormatConvert>(PixelFormat::RGB888);
+    }
+
+    if (pipeline.get_output_format() == PixelFormat::BGR161616) {
+        pipeline.push_node<ImagePipelineNodeFormatConvert>(PixelFormat::RGB161616);
+    }
+
+    return pipeline.get_image();
+}
+
+
+Image read_shuffled_image_from_scanner(Genesys_Device* dev, const ScanSession& session)
+{
+    DBG_HELPER(dbg);
+
+    std::size_t total_bytes = 0;
+    std::size_t pixels_per_line = 0;
+
+    if (dev->model->asic_type == AsicType::GL842 ||
+        dev->model->asic_type == AsicType::GL843 ||
+        dev->model->model_id == ModelId::CANON_5600F)
+    {
+        pixels_per_line = session.output_pixels;
+    } else {
+        // BUG: this selects incorrect pixel number
+        pixels_per_line = session.params.pixels;
+    }
+
+    // FIXME: the current calculation is likely incorrect on non-GL843 implementations,
+    // but this needs checking. Note the extra line when computing size.
+    if (dev->model->asic_type == AsicType::GL842 ||
+        dev->model->asic_type == AsicType::GL843 ||
+        dev->model->model_id == ModelId::CANON_5600F)
+    {
+        total_bytes = session.output_total_bytes_raw;
+    } else {
+        total_bytes = session.params.channels * 2 * pixels_per_line * (session.params.lines + 1);
+    }
+
+    auto format = create_pixel_format(session.params.depth,
+                                      dev->model->is_cis ? 1 : session.params.channels,
+                                      dev->model->line_mode_color_order);
+
+    // auto width = get_pixels_from_row_bytes(format, session.output_line_bytes_raw);
+    auto width = pixels_per_line;
+    auto height = session.params.lines + 1; // BUG: incorrect
+    if (dev->model->asic_type == AsicType::GL842 ||
+        dev->model->asic_type == AsicType::GL843 ||
+        dev->model->model_id == ModelId::CANON_5600F)
+    {
+        height = session.optical_line_count;
+    }
+
+    Image image(width, height, format);
+
+    auto max_bytes = image.get_row_bytes() * height;
+    if (total_bytes > max_bytes) {
+        throw SaneException("Trying to read too much data %zu (max %zu)", total_bytes, max_bytes);
+    }
+    if (total_bytes != max_bytes) {
+        DBG(DBG_info, "WARNING %s: trying to read not enough data (%zu, full fill %zu)\n", __func__,
+            total_bytes, max_bytes);
+    }
+
+    sanei_genesys_read_data_from_scanner(dev, image.get_row_ptr(0), total_bytes);
+
+    ImagePipelineStack pipeline;
+    pipeline.push_first_node<ImagePipelineNodeImageSource>(image);
+
+    if (session.segment_count > 1) {
+        auto output_width = session.output_segment_pixel_group_count * session.segment_count;
+        pipeline.push_node<ImagePipelineNodeDesegment>(output_width, dev->segment_order,
+                                                       session.conseq_pixel_dist,
+                                                       1, 1);
+    }
+
+    if (session.params.depth == 16) {
+        unsigned num_swaps = 0;
+        if (has_flag(dev->model->flags, ModelFlag::SWAP_16BIT_DATA)) {
+            num_swaps++;
+        }
+#ifdef WORDS_BIGENDIAN
+        num_swaps++;
 #endif
+        if (num_swaps % 2 != 0) {
+            dev->pipeline.push_node<ImagePipelineNodeSwap16BitEndian>();
+        }
+    }
+
+    if (has_flag(dev->model->flags, ModelFlag::INVERT_PIXEL_DATA)) {
+        pipeline.push_node<ImagePipelineNodeInvert>();
+    }
 
     if (dev->model->is_cis && session.params.channels == 3) {
-        dev->pipeline.push_node<ImagePipelineNodeMergeMonoLines>(dev->model->line_mode_color_order);
+        pipeline.push_node<ImagePipelineNodeMergeMonoLines>(dev->model->line_mode_color_order);
     }
 
-    if (dev->pipeline.get_output_format() == PixelFormat::BGR888) {
-        dev->pipeline.push_node<ImagePipelineNodeFormatConvert>(PixelFormat::RGB888);
+    if (pipeline.get_output_format() == PixelFormat::BGR888) {
+        pipeline.push_node<ImagePipelineNodeFormatConvert>(PixelFormat::RGB888);
     }
 
-    if (dev->pipeline.get_output_format() == PixelFormat::BGR161616) {
-        dev->pipeline.push_node<ImagePipelineNodeFormatConvert>(PixelFormat::RGB161616);
+    if (pipeline.get_output_format() == PixelFormat::BGR161616) {
+        pipeline.push_node<ImagePipelineNodeFormatConvert>(PixelFormat::RGB161616);
     }
 
     return pipeline.get_image();
@@ -600,34 +597,27 @@ void sanei_genesys_set_lamp_power(Genesys_Device* dev, const Genesys_Sensor& sen
 
         if (dev->model->asic_type == AsicType::GL843) {
             regs_set_exposure(dev->model->asic_type, regs, sensor.exposure);
+        }
 
-            // we don't actually turn on lamp on infrared scan
-            if ((dev->model->model_id == ModelId::CANON_8400F ||
-                 dev->model->model_id == ModelId::CANON_8600F ||
-                 dev->model->model_id == ModelId::PLUSTEK_OPTICFILM_7200I ||
-                 dev->model->model_id == ModelId::PLUSTEK_OPTICFILM_7500I) &&
-                dev->settings.scan_method == ScanMethod::TRANSPARENCY_INFRARED)
-            {
-                regs.find_reg(0x03).value &= ~REG_0x03_LAMPPWR;
-            }
+        // we don't actually turn on lamp on infrared scan
+        if ((dev->model->model_id == ModelId::CANON_8400F ||
+             dev->model->model_id == ModelId::CANON_8600F ||
+             dev->model->model_id == ModelId::PLUSTEK_OPTICFILM_7200I ||
+             dev->model->model_id == ModelId::PLUSTEK_OPTICFILM_7500I ||
+             dev->model->model_id == ModelId::PLUSTEK_OPTICFILM_8200I) &&
+            dev->settings.scan_method == ScanMethod::TRANSPARENCY_INFRARED)
+        {
+            regs.find_reg(0x03).value &= ~REG_0x03_LAMPPWR;
         }
     } else {
         regs.find_reg(0x03).value &= ~REG_0x03_LAMPPWR;
 
         if (dev->model->asic_type == AsicType::GL841) {
-            regs_set_exposure(dev->model->asic_type, regs, {0x0101, 0x0101, 0x0101});
+            regs_set_exposure(dev->model->asic_type, regs, sanei_genesys_fixup_exposure({0, 0, 0}));
             regs.set8(0x19, 0xff);
         }
-
-        if (dev->model->asic_type == AsicType::GL843) {
-            if (dev->model->model_id == ModelId::PANASONIC_KV_SS080 ||
-                dev->model->model_id == ModelId::HP_SCANJET_4850C ||
-                dev->model->model_id == ModelId::HP_SCANJET_G4010 ||
-                dev->model->model_id == ModelId::HP_SCANJET_G4050)
-            {
-                // BUG: datasheet says we shouldn't set exposure to zero
-                regs_set_exposure(dev->model->asic_type, regs, {0, 0, 0});
-            }
+        if (dev->model->model_id == ModelId::CANON_5600F) {
+            regs_set_exposure(dev->model->asic_type, regs, sanei_genesys_fixup_exposure({0, 0, 0}));
         }
     }
     regs.state.is_lamp_on = set;
@@ -786,218 +776,144 @@ void sanei_genesys_send_gamma_table(Genesys_Device* dev, const Genesys_Sensor& s
     }
 }
 
-static unsigned align_int_up(unsigned num, unsigned alignment)
-{
-    unsigned mask = alignment - 1;
-    if (num & mask)
-        num = (num & ~mask) + alignment;
-    return num;
-}
-
-void compute_session_buffer_sizes(AsicType asic, ScanSession& s)
+void compute_session_pixel_offsets(const Genesys_Device* dev, ScanSession& s,
+                                   const Genesys_Sensor& sensor)
 {
-    size_t line_bytes = s.output_line_bytes;
-    size_t line_bytes_stagger = s.output_line_bytes;
-
-    if (asic != AsicType::GL646) {
-        // BUG: this is historical artifact and should be removed. Note that buffer sizes affect
-        // how often we request the scanner for data and thus change the USB traffic.
-        line_bytes_stagger =
-                multiply_by_depth_ceil(s.optical_pixels, s.params.depth) * s.params.channels;
-    }
-
-    struct BufferConfig {
-        size_t* result_size = nullptr;
-        size_t lines = 0;
-        size_t lines_mult = 0;
-        size_t max_size = 0; // does not apply if 0
-        size_t stagger_lines = 0;
-
-        BufferConfig() = default;
-        BufferConfig(std::size_t* rs, std::size_t l, std::size_t lm, std::size_t ms,
-                     std::size_t sl) :
-            result_size{rs},
-            lines{l},
-            lines_mult{lm},
-            max_size{ms},
-            stagger_lines{sl}
-        {}
-    };
+    if (dev->model->asic_type == AsicType::GL646) {
+        s.pixel_startx += s.output_startx * sensor.full_resolution / s.params.xres;
+        s.pixel_endx = s.pixel_startx + s.optical_pixels * s.full_resolution / s.optical_resolution;
 
-    std::array<BufferConfig, 4> configs;
-    if (asic == AsicType::GL124 || asic == AsicType::GL843) {
-        configs = { {
-            { &s.buffer_size_read, 32, 1, 0, s.max_color_shift_lines + s.num_staggered_lines },
-            { &s.buffer_size_lines, 32, 1, 0, s.max_color_shift_lines + s.num_staggered_lines },
-            { &s.buffer_size_shrink, 16, 1, 0, 0 },
-            { &s.buffer_size_out, 8, 1, 0, 0 },
-        } };
-    } else if (asic == AsicType::GL841) {
-        size_t max_buf = sanei_genesys_get_bulk_max_size(asic);
-        configs = { {
-            { &s.buffer_size_read, 8, 2, max_buf, s.max_color_shift_lines + s.num_staggered_lines },
-            { &s.buffer_size_lines, 8, 2, max_buf, s.max_color_shift_lines + s.num_staggered_lines },
-            { &s.buffer_size_shrink, 8, 1, max_buf, 0 },
-            { &s.buffer_size_out, 8, 1, 0, 0 },
-        } };
-    } else {
-        configs = { {
-            { &s.buffer_size_read, 16, 1, 0, s.max_color_shift_lines + s.num_staggered_lines },
-            { &s.buffer_size_lines, 16, 1, 0, s.max_color_shift_lines + s.num_staggered_lines },
-            { &s.buffer_size_shrink, 8, 1, 0, 0 },
-            { &s.buffer_size_out, 8, 1, 0, 0 },
-        } };
-    }
-
-    for (BufferConfig& config : configs) {
-        size_t buf_size = line_bytes * config.lines;
-        if (config.max_size > 0 && buf_size > config.max_size) {
-            buf_size = (config.max_size / line_bytes) * line_bytes;
+    } else if (dev->model->asic_type == AsicType::GL841 ||
+               dev->model->asic_type == AsicType::GL842 ||
+               dev->model->asic_type == AsicType::GL843 ||
+               dev->model->asic_type == AsicType::GL845 ||
+               dev->model->asic_type == AsicType::GL846 ||
+               dev->model->asic_type == AsicType::GL847)
+    {
+        unsigned startx_xres = s.optical_resolution;
+        if (dev->model->model_id == ModelId::CANON_5600F ||
+            dev->model->model_id == ModelId::CANON_LIDE_90)
+        {
+            if (s.output_resolution == 1200) {
+                startx_xres /= 2;
+            }
+            if (s.output_resolution >= 2400) {
+                startx_xres /= 4;
+            }
         }
-        buf_size *= config.lines_mult;
-        buf_size += line_bytes_stagger * config.stagger_lines;
-        *config.result_size = buf_size;
-    }
-}
-
-void compute_session_pipeline(const Genesys_Device* dev, ScanSession& s)
-{
-    auto channels = s.params.channels;
-    auto depth = s.params.depth;
+        s.pixel_startx = (s.output_startx * startx_xres) / s.params.xres;
+        s.pixel_endx = s.pixel_startx + s.optical_pixels_raw;
 
-    s.pipeline_needs_reorder = true;
-    if (channels != 3 && depth != 16) {
-        s.pipeline_needs_reorder = false;
-    }
-#ifndef WORDS_BIGENDIAN
-    if (channels != 3 && depth == 16) {
-        s.pipeline_needs_reorder = false;
-    }
-    if (channels == 3 && depth == 16 && !dev->model->is_cis &&
-        dev->model->line_mode_color_order == ColorOrder::RGB)
+    } else if (dev->model->asic_type == AsicType::GL124)
     {
-        s.pipeline_needs_reorder = false;
+        s.pixel_startx = s.output_startx * sensor.full_resolution / s.params.xres;
+        s.pixel_endx = s.pixel_startx + s.optical_pixels_raw;
     }
-#endif
-    if (channels == 3 && depth == 8 && !dev->model->is_cis &&
-        dev->model->line_mode_color_order == ColorOrder::RGB)
+
+    // align pixels to correct boundary for unstaggering
+    unsigned needed_x_alignment = std::max(s.stagger_x.size(), s.stagger_y.size());
+    unsigned aligned_pixel_startx = align_multiple_floor(s.pixel_startx, needed_x_alignment);
+    s.pixel_endx -= s.pixel_startx - aligned_pixel_startx;
+    s.pixel_startx = aligned_pixel_startx;
+
+    s.pixel_startx = sensor.pixel_count_ratio.apply(s.pixel_startx);
+    s.pixel_endx = sensor.pixel_count_ratio.apply(s.pixel_endx);
+
+    if (dev->model->model_id == ModelId::PLUSTEK_OPTICFILM_7200 ||
+        dev->model->model_id == ModelId::PLUSTEK_OPTICFILM_7200I ||
+        dev->model->model_id == ModelId::PLUSTEK_OPTICFILM_7300 ||
+        dev->model->model_id == ModelId::PLUSTEK_OPTICFILM_7500I)
     {
-        s.pipeline_needs_reorder = false;
+        s.pixel_startx = align_multiple_floor(s.pixel_startx, sensor.pixel_count_ratio.divisor());
+        s.pixel_endx = align_multiple_floor(s.pixel_endx, sensor.pixel_count_ratio.divisor());
     }
-    s.pipeline_needs_ccd = s.max_color_shift_lines + s.num_staggered_lines > 0;
-    s.pipeline_needs_shrink = dev->settings.requested_pixels != s.output_pixels;
 }
 
-void compute_session_pixel_offsets(const Genesys_Device* dev, ScanSession& s,
-                                   const Genesys_Sensor& sensor)
+unsigned session_adjust_output_pixels(unsigned output_pixels,
+                                      const Genesys_Device& dev, const Genesys_Sensor& sensor,
+                                      unsigned output_xresolution, unsigned output_yresolution,
+                                      bool adjust_output_pixels)
 {
-    unsigned ccd_pixels_per_system_pixel = sensor.ccd_pixels_per_system_pixel();
-
-    if (dev->model->asic_type == AsicType::GL646) {
-
-        // startx cannot be below dummy pixel value
-        s.pixel_startx = sensor.dummy_pixel;
-        if (has_flag(s.params.flags, ScanFlag::USE_XCORRECTION) && sensor.ccd_start_xoffset > 0) {
-            s.pixel_startx = sensor.ccd_start_xoffset;
-        }
-        s.pixel_startx += s.params.startx;
-
-        if (sensor.stagger_config.stagger_at_resolution(s.params.xres, s.params.yres) > 0) {
-            s.pixel_startx |= 1;
-        }
-
-        s.pixel_endx = s.pixel_startx + s.optical_pixels;
-
-        s.pixel_startx /= sensor.ccd_pixels_per_system_pixel() * s.ccd_size_divisor;
-        s.pixel_endx /= sensor.ccd_pixels_per_system_pixel() * s.ccd_size_divisor;
-
-    } else if (dev->model->asic_type == AsicType::GL841) {
-        s.pixel_startx = ((sensor.ccd_start_xoffset + s.params.startx) * s.optical_resolution)
-                                / sensor.optical_res;
+    bool adjust_optical_pixels = !adjust_output_pixels;
+    if (dev.model->model_id == ModelId::CANON_5600F) {
+        adjust_optical_pixels = true;
+        adjust_output_pixels = true;
+    }
+    if (adjust_optical_pixels) {
+        auto optical_resolution = sensor.get_optical_resolution();
 
-        s.pixel_startx += sensor.dummy_pixel + 1;
+        // FIXME: better way would be to compute and return the required multiplier
+        unsigned optical_pixels = (output_pixels * optical_resolution) / output_xresolution;
 
-        if (s.num_staggered_lines > 0 && (s.pixel_startx & 1) == 0) {
-            s.pixel_startx++;
+        if (dev.model->asic_type == AsicType::GL841 ||
+            dev.model->asic_type == AsicType::GL842)
+        {
+            optical_pixels = align_multiple_ceil(optical_pixels, 2);
         }
 
-        /*  In case of SHDAREA, we need to align start on pixel average factor, startx is
-            different than 0 only when calling for function to setup for scan, where shading data
-            needs to be align.
-
-            NOTE: we can check the value of the register here, because we don't set this bit
-            anywhere except in initialization.
-        */
-        const uint8_t REG_0x01_SHDAREA = 0x02;
-        if ((dev->reg.find_reg(0x01).value & REG_0x01_SHDAREA) != 0) {
-            unsigned average_factor = s.optical_resolution / s.params.xres;
-            s.pixel_startx = align_multiple_floor(s.pixel_startx, average_factor);
+        if (dev.model->asic_type == AsicType::GL646 && output_xresolution == 400) {
+            optical_pixels = align_multiple_floor(optical_pixels, 6);
         }
 
-        s.pixel_endx = s.pixel_startx + s.optical_pixels;
-
-    } else if (dev->model->asic_type == AsicType::GL843) {
-
-        s.pixel_startx = (s.params.startx + sensor.dummy_pixel) / ccd_pixels_per_system_pixel;
-        s.pixel_endx = s.pixel_startx + s.optical_pixels / ccd_pixels_per_system_pixel;
-
-        s.pixel_startx /= s.hwdpi_divisor;
-        s.pixel_endx /= s.hwdpi_divisor;
-
-        // in case of stagger we have to start at an odd coordinate
-        bool stagger_starts_even = dev->model->model_id == ModelId::CANON_8400F;
-        if (s.num_staggered_lines > 0) {
-            if (!stagger_starts_even && (s.pixel_startx & 1) == 0) {
-                s.pixel_startx++;
-                s.pixel_endx++;
-            } else if (stagger_starts_even && (s.pixel_startx & 1) != 0) {
-                s.pixel_startx++;
-                s.pixel_endx++;
+        if (dev.model->asic_type == AsicType::GL843) {
+            // ensure the number of optical pixels is divisible by 2.
+            // In quarter-CCD mode optical_pixels is 4x larger than the actual physical number
+            optical_pixels = align_multiple_ceil(optical_pixels,
+                                                 2 * sensor.full_resolution / optical_resolution);
+            if (dev.model->model_id == ModelId::PLUSTEK_OPTICFILM_7200 ||
+                dev.model->model_id == ModelId::PLUSTEK_OPTICFILM_7200I ||
+                dev.model->model_id == ModelId::PLUSTEK_OPTICFILM_7300 ||
+                dev.model->model_id == ModelId::PLUSTEK_OPTICFILM_7400 ||
+                dev.model->model_id == ModelId::PLUSTEK_OPTICFILM_7500I ||
+                dev.model->model_id == ModelId::PLUSTEK_OPTICFILM_8200I)
+            {
+                optical_pixels = align_multiple_ceil(optical_pixels, 16);
             }
         }
+        output_pixels = (optical_pixels * output_xresolution) / optical_resolution;
+    }
 
-    } else if (dev->model->asic_type == AsicType::GL845 ||
-               dev->model->asic_type == AsicType::GL846 ||
-               dev->model->asic_type == AsicType::GL847)
-    {
-        s.pixel_startx = s.params.startx;
-
-        if (s.num_staggered_lines > 0) {
-            s.pixel_startx |= 1;
-        }
-
-        s.pixel_startx += sensor.ccd_start_xoffset * ccd_pixels_per_system_pixel;
-        s.pixel_endx = s.pixel_startx + s.optical_pixels_raw;
-
-        s.pixel_startx /= s.hwdpi_divisor * s.segment_count * ccd_pixels_per_system_pixel;
-        s.pixel_endx /= s.hwdpi_divisor * s.segment_count * ccd_pixels_per_system_pixel;
-
-    } else if (dev->model->asic_type == AsicType::GL124) {
-        s.pixel_startx = s.params.startx;
+    if (adjust_output_pixels) {
+        // TODO: the following may no longer be needed but were applied historically.
 
-        if (s.num_staggered_lines > 0) {
-            s.pixel_startx |= 1;
+        // we need an even pixels number
+        // TODO invert test logic or generalize behaviour across all ASICs
+        if (has_flag(dev.model->flags, ModelFlag::SIS_SENSOR) ||
+            dev.model->asic_type == AsicType::GL847 ||
+            dev.model->asic_type == AsicType::GL124 ||
+            dev.model->asic_type == AsicType::GL845 ||
+            dev.model->asic_type == AsicType::GL846 ||
+            dev.model->asic_type == AsicType::GL843)
+        {
+            if (output_xresolution <= 1200) {
+                output_pixels = align_multiple_floor(output_pixels, 4);
+            } else if (output_xresolution < output_yresolution) {
+                // BUG: this is an artifact of the fact that the resolution was twice as large than
+                // the actual resolution when scanning above the supported scanner X resolution
+                output_pixels = align_multiple_floor(output_pixels, 8);
+            } else {
+                output_pixels = align_multiple_floor(output_pixels, 16);
+            }
         }
 
-        s.pixel_startx /= ccd_pixels_per_system_pixel;
-        // FIXME: should we add sensor.dummy_pxel to pixel_startx at this point?
-        s.pixel_endx = s.pixel_startx + s.optical_pixels / ccd_pixels_per_system_pixel;
-
-        s.pixel_startx /= s.hwdpi_divisor * s.segment_count;
-        s.pixel_endx /= s.hwdpi_divisor * s.segment_count;
-
-        std::uint32_t segcnt = (sensor.custom_regs.get_value(gl124::REG_SEGCNT) << 16) +
-                               (sensor.custom_regs.get_value(gl124::REG_SEGCNT + 1) << 8) +
-                                sensor.custom_regs.get_value(gl124::REG_SEGCNT + 2);
-        if (s.pixel_endx == segcnt) {
-            s.pixel_endx = 0;
+        // corner case for true lineart for sensor with several segments or when xres is doubled
+        // to match yres */
+        if (output_xresolution >= 1200 && (
+                    dev.model->asic_type == AsicType::GL124 ||
+                    dev.model->asic_type == AsicType::GL847 ||
+                    dev.session.params.xres < dev.session.params.yres))
+        {
+            if (output_xresolution < output_yresolution) {
+                // FIXME: this is an artifact of the fact that the resolution was twice as large than
+                // the actual resolution when scanning above the supported scanner X resolution
+                output_pixels = align_multiple_floor(output_pixels, 8);
+            } else {
+                output_pixels = align_multiple_floor(output_pixels, 16);
+            }
         }
     }
 
-    s.pixel_count_multiplier = sensor.pixel_count_multiplier;
-
-    s.pixel_startx *= sensor.pixel_count_multiplier;
-    s.pixel_endx *= sensor.pixel_count_multiplier;
+    return output_pixels;
 }
 
 void compute_session(const Genesys_Device* dev, ScanSession& s, const Genesys_Sensor& sensor)
@@ -1011,68 +927,36 @@ void compute_session(const Genesys_Device* dev, ScanSession& s, const Genesys_Se
         throw SaneException("Unsupported depth setting %d", s.params.depth);
     }
 
-    unsigned ccd_pixels_per_system_pixel = sensor.ccd_pixels_per_system_pixel();
-
     // compute optical and output resolutions
-
-    if (dev->model->asic_type == AsicType::GL843) {
-        // FIXME: this may be incorrect, but need more scanners to test
-        s.hwdpi_divisor = sensor.get_hwdpi_divisor_for_dpi(s.params.xres);
-    } else {
-        s.hwdpi_divisor = sensor.get_hwdpi_divisor_for_dpi(s.params.xres * ccd_pixels_per_system_pixel);
-    }
-
-    s.ccd_size_divisor = sensor.get_ccd_size_divisor_for_dpi(s.params.xres);
-
-    if (dev->model->asic_type == AsicType::GL646) {
-        s.optical_resolution = sensor.optical_res;
-    } else {
-        s.optical_resolution = sensor.optical_res / s.ccd_size_divisor;
-    }
+    s.full_resolution = sensor.full_resolution;
+    s.optical_resolution = sensor.get_optical_resolution();
     s.output_resolution = s.params.xres;
 
+    s.pixel_count_ratio = sensor.pixel_count_ratio;
+
     if (s.output_resolution > s.optical_resolution) {
         throw std::runtime_error("output resolution higher than optical resolution");
     }
 
-    // compute the number of optical pixels that will be acquired by the chip
-    s.optical_pixels = (s.params.pixels * s.optical_resolution) / s.output_resolution;
-    if (s.optical_pixels * s.output_resolution < s.params.pixels * s.optical_resolution) {
-        s.optical_pixels++;
-    }
-
-    if (dev->model->asic_type == AsicType::GL841) {
-        if (s.optical_pixels & 1)
-            s.optical_pixels++;
-    }
-
-    if (dev->model->asic_type == AsicType::GL646 && s.params.xres == 400) {
-        s.optical_pixels = (s.optical_pixels / 6) * 6;
-    }
+    s.output_pixels = session_adjust_output_pixels(s.params.pixels, *dev, sensor,
+                                                   s.params.xres, s.params.yres, false);
 
-    if (dev->model->asic_type == AsicType::GL843) {
-        // ensure the number of optical pixels is divisible by 2.
-        // In quarter-CCD mode optical_pixels is 4x larger than the actual physical number
-        s.optical_pixels = align_int_up(s.optical_pixels, 2 * s.ccd_size_divisor);
+    // Compute the number of optical pixels that will be acquired by the chip.
+    // The necessary alignment requirements have already been computed by
+    // get_session_output_pixels_multiplier
+    s.optical_pixels = (s.output_pixels * s.optical_resolution) / s.output_resolution;
 
-        if (dev->model->model_id == ModelId::PLUSTEK_OPTICFILM_7200I ||
-            dev->model->model_id == ModelId::PLUSTEK_OPTICFILM_7300 ||
-            dev->model->model_id == ModelId::PLUSTEK_OPTICFILM_7500I)
-        {
-            s.optical_pixels = align_int_up(s.optical_pixels, 16);
-        }
-    }
+    if (static_cast<int>(s.params.startx) + sensor.output_pixel_offset < 0)
+        throw SaneException("Invalid sensor.output_pixel_offset");
+    s.output_startx = static_cast<unsigned>(
+                static_cast<int>(s.params.startx) + sensor.output_pixel_offset);
 
-    // after all adjustments on the optical pixels have been made, compute the number of pixels
-    // to retrieve from the chip
-    s.output_pixels = (s.optical_pixels * s.output_resolution) / s.optical_resolution;
+    s.stagger_x = sensor.stagger_x;
+    s.stagger_y = sensor.stagger_y;
 
-    // Note: staggering is not applied for calibration. Staggering starts at 2400 dpi
     s.num_staggered_lines = 0;
-    if (!has_flag(s.params.flags, ScanFlag::IGNORE_LINE_DISTANCE))
-    {
-        s.num_staggered_lines = sensor.stagger_config.stagger_at_resolution(s.params.xres,
-                                                                            s.params.yres);
+    if (!has_flag(s.params.flags, ScanFlag::IGNORE_STAGGER_OFFSET)) {
+        s.num_staggered_lines = s.stagger_y.max_shift() * s.params.yres / s.params.xres;
     }
 
     s.color_shift_lines_r = dev->model->ld_shift_r;
@@ -1091,12 +975,14 @@ void compute_session(const Genesys_Device* dev, ScanSession& s, const Genesys_Se
     s.color_shift_lines_b = (s.color_shift_lines_b * s.params.yres) / dev->motor.base_ydpi;
 
     s.max_color_shift_lines = 0;
-    if (s.params.channels > 1 && !has_flag(s.params.flags, ScanFlag::IGNORE_LINE_DISTANCE)) {
+    if (s.params.channels > 1 && !has_flag(s.params.flags, ScanFlag::IGNORE_COLOR_OFFSET)) {
         s.max_color_shift_lines = std::max(s.color_shift_lines_r, std::max(s.color_shift_lines_g,
                                                                            s.color_shift_lines_b));
     }
 
     s.output_line_count = s.params.lines + s.max_color_shift_lines + s.num_staggered_lines;
+    s.optical_line_count = dev->model->is_cis ? s.output_line_count * s.params.channels
+                                              : s.output_line_count;
 
     s.output_channel_bytes = multiply_by_depth_ceil(s.output_pixels, s.params.depth);
     s.output_line_bytes = s.output_channel_bytes * s.params.channels;
@@ -1107,29 +993,62 @@ void compute_session(const Genesys_Device* dev, ScanSession& s, const Genesys_Se
     s.output_line_bytes_raw = s.output_line_bytes;
     s.conseq_pixel_dist = 0;
 
-    if (dev->model->asic_type == AsicType::GL845 ||
-        dev->model->asic_type == AsicType::GL846 ||
-        dev->model->asic_type == AsicType::GL847)
+    // FIXME: Use ModelFlag::SIS_SENSOR
+    if ((dev->model->asic_type == AsicType::GL845 ||
+         dev->model->asic_type == AsicType::GL846 ||
+         dev->model->asic_type == AsicType::GL847) &&
+        dev->model->model_id != ModelId::PLUSTEK_OPTICFILM_7400 &&
+        dev->model->model_id != ModelId::PLUSTEK_OPTICFILM_8200I)
     {
         if (s.segment_count > 1) {
             s.conseq_pixel_dist = sensor.segment_size;
 
-            // in case of multi-segments sensor, we have to add the width of the sensor crossed by
-            // the scan area
-            unsigned extra_segment_scan_area = align_multiple_ceil(s.conseq_pixel_dist, 2);
-            extra_segment_scan_area *= s.segment_count - 1;
-            extra_segment_scan_area *= s.hwdpi_divisor * s.segment_count;
-            extra_segment_scan_area *= ccd_pixels_per_system_pixel;
+            // in case of multi-segments sensor, we have expand the scan area to sensor boundary
+            if (dev->model->model_id == ModelId::CANON_5600F) {
+                unsigned startx_xres = s.optical_resolution;
+                if (dev->model->model_id == ModelId::CANON_5600F) {
+                    if (s.output_resolution == 1200) {
+                        startx_xres /= 2;
+                    }
+                    if (s.output_resolution >= 2400) {
+                        startx_xres /= 4;
+                    }
+                }
+                unsigned optical_startx = s.output_startx * startx_xres / s.params.xres;
+                unsigned optical_endx = optical_startx + s.optical_pixels;
 
-            s.optical_pixels_raw += extra_segment_scan_area;
+                unsigned multi_segment_size_output = s.segment_count * s.conseq_pixel_dist;
+                unsigned multi_segment_size_optical =
+                        (multi_segment_size_output * s.optical_resolution) / s.output_resolution;
+
+                optical_endx = align_multiple_ceil(optical_endx, multi_segment_size_optical);
+                s.optical_pixels_raw = optical_endx - optical_startx;
+                s.optical_pixels_raw = align_multiple_floor(s.optical_pixels_raw,
+                                                            4 * s.optical_resolution / s.output_resolution);
+            } else {
+                // BUG: the following code will likely scan too much. Use the CANON_5600F approach
+                unsigned extra_segment_scan_area = align_multiple_ceil(s.conseq_pixel_dist, 2);
+                extra_segment_scan_area *= s.segment_count - 1;
+                extra_segment_scan_area = s.pixel_count_ratio.apply_inverse(extra_segment_scan_area);
+
+                s.optical_pixels_raw += extra_segment_scan_area;
+            }
         }
 
-        s.output_line_bytes_raw = multiply_by_depth_ceil(
-                    (s.optical_pixels_raw * s.output_resolution) / sensor.optical_res / s.segment_count,
-                    s.params.depth);
+        if (dev->model->model_id == ModelId::CANON_5600F) {
+            auto output_pixels_raw = (s.optical_pixels_raw * s.output_resolution) / s.optical_resolution;
+            auto output_channel_bytes_raw = multiply_by_depth_ceil(output_pixels_raw, s.params.depth);
+            s.output_line_bytes_raw = output_channel_bytes_raw * s.params.channels;
+        } else {
+            s.output_line_bytes_raw = multiply_by_depth_ceil(
+                        (s.optical_pixels_raw * s.output_resolution) / sensor.full_resolution / s.segment_count,
+                        s.params.depth);
+        }
     }
 
-    if (dev->model->asic_type == AsicType::GL841) {
+    if (dev->model->asic_type == AsicType::GL841 ||
+        dev->model->asic_type == AsicType::GL842)
+    {
         if (dev->model->is_cis) {
             s.output_line_bytes_raw = s.output_channel_bytes;
         }
@@ -1139,27 +1058,43 @@ void compute_session(const Genesys_Device* dev, ScanSession& s, const Genesys_Se
         if (dev->model->is_cis) {
             s.output_line_bytes_raw = s.output_channel_bytes;
         }
-        s.conseq_pixel_dist = s.output_pixels / s.ccd_size_divisor / s.segment_count;
+        s.conseq_pixel_dist = s.output_pixels / (s.full_resolution / s.optical_resolution) / s.segment_count;
     }
 
-    if (dev->model->asic_type == AsicType::GL843) {
-        s.conseq_pixel_dist = s.output_pixels / s.segment_count;
+    if (dev->model->asic_type == AsicType::GL842 ||
+        dev->model->asic_type == AsicType::GL843)
+    {
+        if (dev->model->is_cis) {
+            if (s.segment_count > 1) {
+                s.conseq_pixel_dist = sensor.segment_size;
+            }
+        } else {
+            s.conseq_pixel_dist = s.output_pixels / s.segment_count;
+        }
     }
 
     s.output_segment_pixel_group_count = 0;
     if (dev->model->asic_type == AsicType::GL124 ||
+        dev->model->asic_type == AsicType::GL842 ||
         dev->model->asic_type == AsicType::GL843)
     {
-        s.output_segment_pixel_group_count = multiply_by_depth_ceil(
-            s.output_pixels / s.ccd_size_divisor / s.segment_count, s.params.depth);
+        s.output_segment_pixel_group_count = s.output_pixels /
+                (s.full_resolution / s.optical_resolution * s.segment_count);
     }
+
+    if (dev->model->model_id == ModelId::CANON_LIDE_90) {
+        s.output_segment_pixel_group_count = s.output_pixels / s.segment_count;
+    }
+
     if (dev->model->asic_type == AsicType::GL845 ||
         dev->model->asic_type == AsicType::GL846 ||
         dev->model->asic_type == AsicType::GL847)
     {
-        s.output_segment_pixel_group_count = multiply_by_depth_ceil(
-            s.optical_pixels / (s.hwdpi_divisor * s.segment_count * ccd_pixels_per_system_pixel),
-            s.params.depth);
+        if (dev->model->model_id == ModelId::CANON_5600F) {
+            s.output_segment_pixel_group_count = s.output_pixels / s.segment_count;
+        } else {
+            s.output_segment_pixel_group_count = s.pixel_count_ratio.apply(s.optical_pixels);
+        }
     }
 
     s.output_line_bytes_requested = multiply_by_depth_ceil(
@@ -1167,11 +1102,16 @@ void compute_session(const Genesys_Device* dev, ScanSession& s, const Genesys_Se
 
     s.output_total_bytes_raw = s.output_line_bytes_raw * s.output_line_count;
     s.output_total_bytes = s.output_line_bytes * s.output_line_count;
+    if (dev->model->model_id == ModelId::CANON_LIDE_90) {
+        s.output_total_bytes_raw *= s.params.channels;
+        s.output_total_bytes *= s.params.channels;
+    }
 
-    compute_session_buffer_sizes(dev->model->asic_type, s);
-    compute_session_pipeline(dev, s);
+    s.buffer_size_read = s.output_line_bytes_raw * 64;
     compute_session_pixel_offsets(dev, s, sensor);
 
+    s.shading_pixel_offset = sensor.shading_pixel_offset;
+
     if (dev->model->asic_type == AsicType::GL124 ||
         dev->model->asic_type == AsicType::GL845 ||
         dev->model->asic_type == AsicType::GL846)
@@ -1179,7 +1119,10 @@ void compute_session(const Genesys_Device* dev, ScanSession& s, const Genesys_Se
         s.enable_ledadd = (s.params.channels == 1 && dev->model->is_cis && dev->settings.true_gray);
     }
 
+    s.use_host_side_calib = sensor.use_host_side_calib;
+
     if (dev->model->asic_type == AsicType::GL841 ||
+        dev->model->asic_type == AsicType::GL842 ||
         dev->model->asic_type == AsicType::GL843)
     {
         // no 16 bit gamma for this ASIC
@@ -1194,177 +1137,166 @@ void compute_session(const Genesys_Device* dev, ScanSession& s, const Genesys_Se
     debug_dump(DBG_info, s);
 }
 
-static std::size_t get_usb_buffer_read_size(AsicType asic, const ScanSession& session)
+ImagePipelineStack build_image_pipeline(const Genesys_Device& dev, const ScanSession& session,
+                                        unsigned pipeline_index, bool log_image_data)
 {
-    switch (asic) {
-        case AsicType::GL646:
-            // buffer not used on this chip set
-            return 1;
-
-        case AsicType::GL124:
-            // BUG: we shouldn't multiply by channels here nor divide by ccd_size_divisor
-            return session.output_line_bytes_raw / session.ccd_size_divisor * session.params.channels;
-
-        case AsicType::GL845:
-        case AsicType::GL846:
-        case AsicType::GL847:
-            // BUG: we shouldn't multiply by channels here
-            return session.output_line_bytes_raw * session.params.channels;
-
-        case AsicType::GL843:
-            return session.output_line_bytes_raw * 2;
-
-        default:
-            throw SaneException("Unknown asic type");
-    }
-}
-
-static FakeBufferModel get_fake_usb_buffer_model(const ScanSession& session)
-{
-    FakeBufferModel model;
-    model.push_step(session.buffer_size_read, 1);
-
-    if (session.pipeline_needs_reorder) {
-        model.push_step(session.buffer_size_lines, session.output_line_bytes);
-    }
-    if (session.pipeline_needs_ccd) {
-        model.push_step(session.buffer_size_shrink, session.output_line_bytes);
-    }
-    if (session.pipeline_needs_shrink) {
-        model.push_step(session.buffer_size_out, session.output_line_bytes);
-    }
-
-    return model;
-}
-
-void build_image_pipeline(Genesys_Device* dev, const ScanSession& session)
-{
-    static unsigned s_pipeline_index = 0;
-
-    s_pipeline_index++;
-
     auto format = create_pixel_format(session.params.depth,
-                                      dev->model->is_cis ? 1 : session.params.channels,
-                                      dev->model->line_mode_color_order);
+                                      dev.model->is_cis ? 1 : session.params.channels,
+                                      dev.model->line_mode_color_order);
     auto depth = get_pixel_format_depth(format);
     auto width = get_pixels_from_row_bytes(format, session.output_line_bytes_raw);
 
-    auto read_data_from_usb = [dev](std::size_t size, std::uint8_t* data)
+    auto read_data_from_usb = [&dev](std::size_t size, std::uint8_t* data)
     {
-        dev->interface->bulk_read_data(0x45, data, size);
+        DBG(DBG_info, "read_data_from_usb: reading %zu bytes\n", size);
+        auto begin = std::chrono::high_resolution_clock::now();
+        dev.interface->bulk_read_data(0x45, data, size);
+        auto end = std::chrono::high_resolution_clock::now();
+        float us = std::chrono::duration_cast<std::chrono::microseconds>(end - begin).count();
+        float speed = size / us; // bytes/us == MB/s
+        DBG(DBG_info, "read_data_from_usb: reading %zu bytes finished %f MB/s\n", size, speed);
         return true;
     };
 
-    auto lines = session.output_line_count * (dev->model->is_cis ? session.params.channels : 1);
+    auto debug_prefix = "gl_pipeline_" + std::to_string(pipeline_index);
 
-    dev->pipeline.clear();
+    ImagePipelineStack pipeline;
 
-    // FIXME: here we are complicating things for the time being to preserve the existing behaviour
-    // This allows to be sure that the changes to the image pipeline have not introduced
-    // regressions.
+    auto lines = session.optical_line_count;
+    auto buffer_size = session.buffer_size_read;
 
-    if (session.segment_count > 1) {
-        // BUG: we're reading one line too much
-        dev->pipeline.push_first_node<ImagePipelineNodeBufferedCallableSource>(
-                width, lines + 1, format,
-                get_usb_buffer_read_size(dev->model->asic_type, session), read_data_from_usb);
+    // At least GL841 requires reads to be aligned to 2 bytes and will fail on some devices on
+    // certain circumstances.
+    buffer_size = align_multiple_ceil(buffer_size, 2);
+
+    auto& src_node = pipeline.push_first_node<ImagePipelineNodeBufferedCallableSource>(
+                          width, lines, format, buffer_size, read_data_from_usb);
+    src_node.set_last_read_multiple(2);
 
+    if (log_image_data) {
+        pipeline.push_node<ImagePipelineNodeDebug>(debug_prefix + "_0_from_usb.tiff");
+    }
+
+    if (session.segment_count > 1) {
         auto output_width = session.output_segment_pixel_group_count * session.segment_count;
-        dev->pipeline.push_node<ImagePipelineNodeDesegment>(output_width, dev->segment_order,
+        pipeline.push_node<ImagePipelineNodeDesegment>(output_width, dev.segment_order,
                                                             session.conseq_pixel_dist,
                                                             1, 1);
-    } else {
-        auto read_bytes_left_after_deseg = session.output_line_bytes * session.output_line_count;
-        if (dev->model->asic_type == AsicType::GL646) {
-            read_bytes_left_after_deseg *= dev->model->is_cis ? session.params.channels : 1;
-        }
 
-        dev->pipeline.push_first_node<ImagePipelineNodeBufferedGenesysUsb>(
-                width, lines, format, read_bytes_left_after_deseg,
-                get_fake_usb_buffer_model(session), read_data_from_usb);
+        if (log_image_data) {
+            pipeline.push_node<ImagePipelineNodeDebug>(debug_prefix + "_1_after_desegment.tiff");
+        }
     }
 
-    if (DBG_LEVEL >= DBG_io2) {
-        dev->pipeline.push_node<ImagePipelineNodeDebug>("gl_pipeline_" +
-                                                        std::to_string(s_pipeline_index) +
-                                                        "_0_before_swap.pnm");
-    }
+    if (depth == 16) {
+        unsigned num_swaps = 0;
+        if (has_flag(dev.model->flags, ModelFlag::SWAP_16BIT_DATA)) {
+            num_swaps++;
+        }
+#ifdef WORDS_BIGENDIAN
+        num_swaps++;
+#endif
+        if (num_swaps % 2 != 0) {
+            pipeline.push_node<ImagePipelineNodeSwap16BitEndian>();
 
-    if ((dev->model->flags & GENESYS_FLAG_16BIT_DATA_INVERTED) && depth == 16) {
-        dev->pipeline.push_node<ImagePipelineNodeSwap16BitEndian>();
+            if (log_image_data) {
+                pipeline.push_node<ImagePipelineNodeDebug>(debug_prefix + "_2_after_swap.tiff");
+            }
+        }
     }
 
-#ifdef WORDS_BIGENDIAN
-    if (depth == 16) {
-        dev->pipeline.push_node<ImagePipelineNodeSwap16BitEndian>();
+    if (has_flag(dev.model->flags, ModelFlag::INVERT_PIXEL_DATA)) {
+        pipeline.push_node<ImagePipelineNodeInvert>();
+
+        if (log_image_data) {
+            pipeline.push_node<ImagePipelineNodeDebug>(debug_prefix + "_3_after_invert.tiff");
+        }
     }
-#endif
 
-    if (DBG_LEVEL >= DBG_io2) {
-        dev->pipeline.push_node<ImagePipelineNodeDebug>("gl_pipeline_" +
-                                                        std::to_string(s_pipeline_index) +
-                                                        "_1_after_swap.pnm");
+    if (dev.model->is_cis && session.params.channels == 3) {
+        pipeline.push_node<ImagePipelineNodeMergeMonoLines>(dev.model->line_mode_color_order);
+
+        if (log_image_data) {
+            pipeline.push_node<ImagePipelineNodeDebug>(debug_prefix + "_4_after_merge_mono.tiff");
+        }
     }
 
-    if (dev->model->is_cis && session.params.channels == 3) {
-        dev->pipeline.push_node<ImagePipelineNodeMergeMonoLines>(dev->model->line_mode_color_order);
+    if (pipeline.get_output_format() == PixelFormat::BGR888) {
+        pipeline.push_node<ImagePipelineNodeFormatConvert>(PixelFormat::RGB888);
     }
 
-    if (dev->pipeline.get_output_format() == PixelFormat::BGR888) {
-        dev->pipeline.push_node<ImagePipelineNodeFormatConvert>(PixelFormat::RGB888);
+    if (pipeline.get_output_format() == PixelFormat::BGR161616) {
+        pipeline.push_node<ImagePipelineNodeFormatConvert>(PixelFormat::RGB161616);
     }
 
-    if (dev->pipeline.get_output_format() == PixelFormat::BGR161616) {
-        dev->pipeline.push_node<ImagePipelineNodeFormatConvert>(PixelFormat::RGB161616);
+    if (log_image_data) {
+        pipeline.push_node<ImagePipelineNodeDebug>(debug_prefix + "_5_after_format.tiff");
     }
 
     if (session.max_color_shift_lines > 0 && session.params.channels == 3) {
-        dev->pipeline.push_node<ImagePipelineNodeComponentShiftLines>(
+        pipeline.push_node<ImagePipelineNodeComponentShiftLines>(
                     session.color_shift_lines_r,
                     session.color_shift_lines_g,
                     session.color_shift_lines_b);
+
+        if (log_image_data) {
+            pipeline.push_node<ImagePipelineNodeDebug>(debug_prefix + "_6_after_color_unshift.tiff");
+        }
     }
 
-    if (DBG_LEVEL >= DBG_io2) {
-        dev->pipeline.push_node<ImagePipelineNodeDebug>("gl_pipeline_" +
-                                                        std::to_string(s_pipeline_index) +
-                                                        "_2_after_shift.pnm");
+    if (!session.stagger_x.empty()) {
+        // FIXME: the image will be scaled to requested pixel count without regard to the reduction
+        // of image size in this step.
+        pipeline.push_node<ImagePipelineNodePixelShiftColumns>(session.stagger_x.shifts());
+
+        if (log_image_data) {
+            pipeline.push_node<ImagePipelineNodeDebug>(debug_prefix + "_7_after_x_unstagger.tiff");
+        }
     }
 
     if (session.num_staggered_lines > 0) {
-        std::vector<std::size_t> shifts{0, session.num_staggered_lines};
-        dev->pipeline.push_node<ImagePipelineNodePixelShiftLines>(shifts);
-    }
+        pipeline.push_node<ImagePipelineNodePixelShiftLines>(session.stagger_y.shifts());
 
-    if (DBG_LEVEL >= DBG_io2) {
-        dev->pipeline.push_node<ImagePipelineNodeDebug>("gl_pipeline_" +
-                                                        std::to_string(s_pipeline_index) +
-                                                        "_3_after_stagger.pnm");
+        if (log_image_data) {
+            pipeline.push_node<ImagePipelineNodeDebug>(debug_prefix + "_8_after_y_unstagger.tiff");
+        }
     }
 
-    if ((dev->model->flags & GENESYS_FLAG_CALIBRATION_HOST_SIDE) &&
-        !(dev->model->flags & GENESYS_FLAG_NO_CALIBRATION))
+    if (session.use_host_side_calib &&
+        !has_flag(dev.model->flags, ModelFlag::DISABLE_SHADING_CALIBRATION) &&
+        !has_flag(session.params.flags, ScanFlag::DISABLE_SHADING))
     {
-        dev->pipeline.push_node<ImagePipelineNodeCalibrate>(dev->dark_average_data,
-                                                            dev->white_average_data);
+        unsigned offset_pixels = session.params.startx + dev.calib_session.shading_pixel_offset;
+        unsigned offset_bytes = offset_pixels * dev.calib_session.params.channels;
+        pipeline.push_node<ImagePipelineNodeCalibrate>(dev.dark_average_data,
+                                                       dev.white_average_data, offset_bytes);
 
-        if (DBG_LEVEL >= DBG_io2) {
-            dev->pipeline.push_node<ImagePipelineNodeDebug>("gl_pipeline_" +
-                                                            std::to_string(s_pipeline_index) +
-                                                            "_4_after_calibrate.pnm");
+        if (log_image_data) {
+            pipeline.push_node<ImagePipelineNodeDebug>(debug_prefix + "_9_after_calibrate.tiff");
         }
     }
 
-    if (session.output_pixels != session.params.get_requested_pixels()) {
-        dev->pipeline.push_node<ImagePipelineNodeScaleRows>(session.params.get_requested_pixels());
+    if (pipeline.get_output_width() != session.params.get_requested_pixels()) {
+        pipeline.push_node<ImagePipelineNodeScaleRows>(session.params.get_requested_pixels());
     }
 
-    auto read_from_pipeline = [dev](std::size_t size, std::uint8_t* out_data)
+    return pipeline;
+}
+
+void setup_image_pipeline(Genesys_Device& dev, const ScanSession& session)
+{
+    static unsigned s_pipeline_index = 0;
+
+    s_pipeline_index++;
+
+    dev.pipeline = build_image_pipeline(dev, session, s_pipeline_index, dbg_log_image_data());
+
+    auto read_from_pipeline = [&dev](std::size_t size, std::uint8_t* out_data)
     {
-        (void) size; // will be always equal to dev->pipeline.get_output_row_bytes()
-        return dev->pipeline.get_next_row_data(out_data);
+        (void) size; // will be always equal to dev.pipeline.get_output_row_bytes()
+        return dev.pipeline.get_next_row_data(out_data);
     };
-    dev->pipeline_buffer = ImageBuffer{dev->pipeline.get_output_row_bytes(),
+    dev.pipeline_buffer = ImageBuffer{dev.pipeline.get_output_row_bytes(),
                                        read_from_pipeline};
 }
 
@@ -1394,6 +1326,32 @@ std::uint8_t compute_frontend_gain_wolfson(float value, float target_value)
     return clamp(code, 0, 255);
 }
 
+std::uint8_t compute_frontend_gain_lide_80(float value, float target_value)
+{
+    int code = static_cast<int>((target_value / value) * 12);
+    return clamp(code, 0, 255);
+}
+
+std::uint8_t compute_frontend_gain_wolfson_gl841(float value, float target_value)
+{
+    // this code path is similar to what generic wolfson code path uses and uses similar constants,
+    // but is likely incorrect.
+    float inv_gain = target_value / value;
+    inv_gain *= 0.69f;
+    int code = static_cast<int>(283 - 208 / inv_gain);
+    return clamp(code, 0, 255);
+}
+
+std::uint8_t compute_frontend_gain_wolfson_gl846_gl847_gl124(float value, float target_value)
+{
+    // this code path is similar to what generic wolfson code path uses and uses similar constants,
+    // but is likely incorrect.
+    float inv_gain = target_value / value;
+    int code = static_cast<int>(283 - 208 / inv_gain);
+    return clamp(code, 0, 255);
+}
+
+
 std::uint8_t compute_frontend_gain_analog_devices(float value, float target_value)
 {
     /*  The flow of data through the frontend ADC is as follows (see e.g. AD9826 datasheet)
@@ -1418,13 +1376,22 @@ std::uint8_t compute_frontend_gain_analog_devices(float value, float target_valu
 std::uint8_t compute_frontend_gain(float value, float target_value,
                                    FrontendType frontend_type)
 {
-    if (frontend_type == FrontendType::WOLFSON) {
-        return compute_frontend_gain_wolfson(value, target_value);
-    }
-    if (frontend_type == FrontendType::ANALOG_DEVICES) {
-        return compute_frontend_gain_analog_devices(value, target_value);
+    switch (frontend_type) {
+        case FrontendType::WOLFSON:
+            return compute_frontend_gain_wolfson(value, target_value);
+        case FrontendType::ANALOG_DEVICES:
+            return compute_frontend_gain_analog_devices(value, target_value);
+        case FrontendType::CANON_LIDE_80:
+            return compute_frontend_gain_lide_80(value, target_value);
+        case FrontendType::WOLFSON_GL841:
+            return compute_frontend_gain_wolfson_gl841(value, target_value);
+        case FrontendType::WOLFSON_GL846:
+        case FrontendType::ANALOG_DEVICES_GL847:
+        case FrontendType::WOLFSON_GL124:
+            return compute_frontend_gain_wolfson_gl846_gl847_gl124(value, target_value);
+        default:
+            throw SaneException("Unknown frontend to compute gain for");
     }
-    throw SaneException("Unknown frontend to compute gain for");
 }
 
 /** @brief initialize device
@@ -1436,7 +1403,7 @@ std::uint8_t compute_frontend_gain(float value, float target_value,
  * @param dev device to initialize
  * @param max_regs umber of maximum used registers
  */
-void sanei_genesys_asic_init(Genesys_Device* dev, bool /*max_regs*/)
+void sanei_genesys_asic_init(Genesys_Device* dev)
 {
     DBG_HELPER(dbg);
 
@@ -1486,8 +1453,7 @@ void sanei_genesys_asic_init(Genesys_Device* dev, bool /*max_regs*/)
 
   dev->settings.color_filter = ColorFilter::RED;
 
-  /* duplicate initial values into calibration registers */
-  dev->calib_reg = dev->reg;
+    dev->initial_regs = dev->reg;
 
   const auto& sensor = sanei_genesys_find_sensor_any(dev);
 
@@ -1497,8 +1463,15 @@ void sanei_genesys_asic_init(Genesys_Device* dev, bool /*max_regs*/)
     dev->already_initialized = true;
 
     // Move to home if needed
+    if (dev->model->model_id == ModelId::CANON_8600F) {
+        if (!dev->cmd_set->is_head_home(*dev, ScanHeadId::SECONDARY)) {
+            dev->set_head_pos_unknown(ScanHeadId::SECONDARY);
+        }
+        if (!dev->cmd_set->is_head_home(*dev, ScanHeadId::PRIMARY)) {
+            dev->set_head_pos_unknown(ScanHeadId::SECONDARY);
+        }
+    }
     dev->cmd_set->move_back_home(dev, true);
-    dev->set_head_pos_zero(ScanHeadId::PRIMARY);
 
     // Set powersaving (default = 15 minutes)
     dev->cmd_set->set_powersaving(dev, 15);
@@ -1510,6 +1483,7 @@ void scanner_start_action(Genesys_Device& dev, bool start_motor)
     switch (dev.model->asic_type) {
         case AsicType::GL646:
         case AsicType::GL841:
+        case AsicType::GL842:
         case AsicType::GL843:
         case AsicType::GL845:
         case AsicType::GL846:
@@ -1527,8 +1501,7 @@ void scanner_start_action(Genesys_Device& dev, bool start_motor)
     }
 }
 
-void sanei_genesys_set_dpihw(Genesys_Register_Set& regs, const Genesys_Sensor& sensor,
-                             unsigned dpihw)
+void sanei_genesys_set_dpihw(Genesys_Register_Set& regs, unsigned dpihw)
 {
     // same across GL646, GL841, GL843, GL846, GL847, GL124
     const uint8_t REG_0x05_DPIHW_MASK = 0xc0;
@@ -1537,10 +1510,6 @@ void sanei_genesys_set_dpihw(Genesys_Register_Set& regs, const Genesys_Sensor& s
     const uint8_t REG_0x05_DPIHW_2400 = 0x80;
     const uint8_t REG_0x05_DPIHW_4800 = 0xc0;
 
-    if (sensor.register_dpihw_override != 0) {
-        dpihw = sensor.register_dpihw_override;
-    }
-
     uint8_t dpihw_setting;
     switch (dpihw) {
         case 600:
@@ -1583,6 +1552,12 @@ void regs_set_exposure(AsicType asic_type, Genesys_Register_Set& regs,
             regs.set16(gl841::REG_EXPB, exposure.blue);
             break;
         }
+        case AsicType::GL842: {
+            regs.set16(gl842::REG_EXPR, exposure.red);
+            regs.set16(gl842::REG_EXPG, exposure.green);
+            regs.set16(gl842::REG_EXPB, exposure.blue);
+            break;
+        }
         case AsicType::GL843: {
             regs.set16(gl843::REG_EXPR, exposure.red);
             regs.set16(gl843::REG_EXPG, exposure.green);
@@ -1619,6 +1594,10 @@ void regs_set_optical_off(AsicType asic_type, Genesys_Register_Set& regs)
             regs.find_reg(gl841::REG_0x01).value &= ~gl841::REG_0x01_SCAN;
             break;
         }
+        case AsicType::GL842: {
+            regs.find_reg(gl842::REG_0x01).value &= ~gl842::REG_0x01_SCAN;
+            break;
+        }
         case AsicType::GL843: {
             regs.find_reg(gl843::REG_0x01).value &= ~gl843::REG_0x01_SCAN;
             break;
@@ -1648,6 +1627,8 @@ bool get_registers_gain4_bit(AsicType asic_type, const Genesys_Register_Set& reg
             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::GL842:
+            return static_cast<bool>(regs.get8(gl842::REG_0x06) & gl842::REG_0x06_GAIN4);
         case AsicType::GL843:
             return static_cast<bool>(regs.get8(gl843::REG_0x06) & gl843::REG_0x06_GAIN4);
         case AsicType::GL845:
@@ -1706,79 +1687,78 @@ void sanei_genesys_wait_for_home(Genesys_Device* dev)
     }
 }
 
-/** @brief motor profile
- * search for the database of motor profiles and get the best one. Each
- * profile is at full step and at a reference exposure. Use first entry
- * by default.
- * @param motors motor profile database
- * @param motor_type motor id
- * @param exposure exposure time
- * @return a pointer to a Motor_Profile struct
- */
-const Motor_Profile& sanei_genesys_get_motor_profile(const std::vector<Motor_Profile>& motors,
-                                                     MotorId motor_id, int exposure)
+const MotorProfile* get_motor_profile_ptr(const std::vector<MotorProfile>& profiles,
+                                          unsigned exposure,
+                                          const ScanSession& session)
 {
-  int idx;
+    int best_i = -1;
+
+    for (unsigned i = 0; i < profiles.size(); ++i) {
+        const auto& profile = profiles[i];
 
-  idx=-1;
-    for (std::size_t i = 0; i < motors.size(); ++i) {
-        // exact match
-        if (motors[i].motor_id == motor_id && motors[i].exposure==exposure) {
-            return motors[i];
+        if (!profile.resolutions.matches(session.params.yres)) {
+            continue;
+        }
+        if (!profile.scan_methods.matches(session.params.scan_method)) {
+            continue;
         }
 
-        // closest match
-        if (motors[i].motor_id == motor_id) {
-          /* if profile exposure is higher than the required one,
-           * the entry is a candidate for the closest match */
-            if (motors[i].exposure == 0 || motors[i].exposure >= exposure)
-            {
-              if(idx<0)
-                {
-                  /* no match found yet */
-                  idx=i;
-                }
-              else
-                {
-                  /* test for better match */
-                  if(motors[i].exposure<motors[idx].exposure)
-                    {
-                      idx=i;
-                    }
+        if (profile.max_exposure == exposure) {
+            return &profile;
+        }
+
+        if (profile.max_exposure == 0 || profile.max_exposure >= exposure) {
+            if (best_i < 0) {
+                // no match found yet
+                best_i = i;
+            } else {
+                // test for better match
+                if (profiles[i].max_exposure < profiles[best_i].max_exposure) {
+                    best_i = i;
                 }
             }
         }
     }
 
-  /* default fallback */
-  if(idx<0)
-    {
-      DBG (DBG_warn,"%s: using default motor profile\n",__func__);
-      idx=0;
+    if (best_i < 0) {
+        return nullptr;
+    }
+
+    return &profiles[best_i];
+}
+
+const MotorProfile& get_motor_profile(const std::vector<MotorProfile>& profiles,
+                                      unsigned exposure,
+                                      const ScanSession& session)
+{
+    const auto* profile = get_motor_profile_ptr(profiles, exposure, session);
+    if (profile == nullptr) {
+        throw SaneException("Motor slope is not configured");
     }
 
-    return motors[idx];
+    return *profile;
 }
 
-MotorSlopeTable sanei_genesys_slope_table(AsicType asic_type, int dpi, int exposure, int base_dpi,
-                                          unsigned step_multiplier,
-                                          const Motor_Profile& motor_profile)
+MotorSlopeTable create_slope_table(AsicType asic_type, const Genesys_Motor& motor, unsigned ydpi,
+                                   unsigned exposure, unsigned step_multiplier,
+                                   const MotorProfile& motor_profile)
 {
-    unsigned target_speed_w = ((exposure * dpi) / base_dpi);
+    unsigned target_speed_w = ((exposure * ydpi) / motor.base_ydpi);
 
-    auto table = create_slope_table(motor_profile.slope, target_speed_w, motor_profile.step_type,
-                                    step_multiplier, 2 * step_multiplier,
-                                    get_slope_table_max_size(asic_type));
+    auto table = create_slope_table_for_speed(motor_profile.slope, target_speed_w,
+                                              motor_profile.step_type,
+                                              step_multiplier, 2 * step_multiplier,
+                                              get_slope_table_max_size(asic_type));
     return table;
 }
 
 MotorSlopeTable create_slope_table_fastest(AsicType asic_type, unsigned step_multiplier,
-                                           const Motor_Profile& motor_profile)
+                                           const MotorProfile& motor_profile)
 {
-    return create_slope_table(motor_profile.slope, motor_profile.slope.max_speed_w,
-                              motor_profile.step_type,
-                              step_multiplier, 2 * step_multiplier,
-                              get_slope_table_max_size(asic_type));
+    return create_slope_table_for_speed(motor_profile.slope, motor_profile.slope.max_speed_w,
+                                        motor_profile.step_type,
+                                        step_multiplier, 2 * step_multiplier,
+                                        get_slope_table_max_size(asic_type));
 }
 
 /** @brief returns the lowest possible ydpi for the device