genesys: Improve set_head_pos_unknown() to set status per head

backend/genesys/device.cpp

@@ -124,10 +124,14 @@ unsigned Genesys_Device::head_pos(ScanHeadId scan_head) const
     }
 }
 
-void Genesys_Device::set_head_pos_unknown()
+void Genesys_Device::set_head_pos_unknown(ScanHeadId scan_head)
 {
-    is_head_pos_primary_known_ = false;
-    is_head_pos_secondary_known_ = false;
+    if ((scan_head & ScanHeadId::PRIMARY) != ScanHeadId::NONE) {
+        is_head_pos_primary_known_ = false;
+    }
+    if ((scan_head & ScanHeadId::SECONDARY) != ScanHeadId::NONE) {
+        is_head_pos_secondary_known_ = false;
+    }
 }
 
 void Genesys_Device::set_head_pos_zero(ScanHeadId scan_head)

backend/genesys/device.h

@@ -360,7 +360,7 @@ struct Genesys_Device
 
     bool is_head_pos_known(ScanHeadId scan_head) const;
     unsigned head_pos(ScanHeadId scan_head) const;
-    void set_head_pos_unknown();
+    void set_head_pos_unknown(ScanHeadId scan_head);
     void set_head_pos_zero(ScanHeadId scan_head);
     void advance_head_pos_by_session(ScanHeadId scan_head);
     void advance_head_pos_by_steps(ScanHeadId scan_head, Direction direction, unsigned steps);

backend/genesys/genesys.cpp

@@ -1169,7 +1169,7 @@ void scanner_move_back_home(Genesys_Device& dev, bool wait_until_home)
         // when we come here then the scanner needed too much time for this, so we better stop
         // the motor
         catch_all_exceptions(__func__, [&](){ scanner_stop_action(dev); });
-        dev.set_head_pos_unknown();
+        dev.set_head_pos_unknown(ScanHeadId::PRIMARY | ScanHeadId::SECONDARY);
         throw SaneException(SANE_STATUS_IO_ERROR, "timeout while waiting for scanhead to go home");
     }
     dbg.log(DBG_info, "scanhead is still moving");

backend/genesys/gl646.cpp

@@ -1473,7 +1473,7 @@ void CommandSetGl646::move_back_home(Genesys_Device* dev, bool wait_until_home)
 
   if (!i)			/* the loop counted down to 0, scanner still is busy */
     {
-        dev->set_head_pos_unknown();
+        dev->set_head_pos_unknown(ScanHeadId::PRIMARY | ScanHeadId::SECONDARY);
         throw SaneException(SANE_STATUS_DEVICE_BUSY, "motor is still on: device busy");
     }
 
@@ -1567,7 +1567,7 @@ void CommandSetGl646::move_back_home(Genesys_Device* dev, bool wait_until_home)
         // stop the motor
         catch_all_exceptions(__func__, [&](){ gl646_stop_motor (dev); });
         catch_all_exceptions(__func__, [&](){ end_scan_impl(dev, &dev->reg, true, false); });
-        dev->set_head_pos_unknown();
+        dev->set_head_pos_unknown(ScanHeadId::PRIMARY | ScanHeadId::SECONDARY);
         throw SaneException(SANE_STATUS_IO_ERROR, "timeout while waiting for scanhead to go home");
     }
 

backend/genesys/gl841.cpp

@@ -2183,7 +2183,7 @@ static void gl841_feed(Genesys_Device* dev, int steps)
   /* when we come here then the scanner needed too much time for this, so we better stop the motor */
   gl841_stop_action (dev);
 
-    dev->set_head_pos_unknown();
+    dev->set_head_pos_unknown(ScanHeadId::PRIMARY);
 
     throw SaneException(SANE_STATUS_IO_ERROR, "timeout while waiting for scanhead to go home");
 }
@@ -2279,7 +2279,7 @@ void CommandSetGl841::move_back_home(Genesys_Device* dev, bool wait_until_home)
         // when we come here then the scanner needed too much time for this, so we better stop
         // the motor
         catch_all_exceptions(__func__, [&](){ gl841_stop_action(dev); });
-        dev->set_head_pos_unknown();
+        dev->set_head_pos_unknown(ScanHeadId::PRIMARY);
         throw SaneException(SANE_STATUS_IO_ERROR, "timeout while waiting for scanhead to go home");
     }