1 files changed, 53 insertions, 44 deletions

diff --git a/driver/mouse.c b/driver/mouse.c
index c0e71d5..14782f7 100644
--- a/driver/mouse.c
+++ b/driver/mouse.c
@@ -1,3 +1,6 @@
+//https://wiki.osdev.org/PS/2_Mouse
+//TODO: ignore last packet for 4 packets mouse?
+
 #include <stdint.h>
 
 #include "mouse.h"
@@ -12,16 +15,24 @@
 
 static volatile uint8_t mouse_cycle;
 static volatile uint8_t mouse_byte[3];
-static volatile int16_t mouse_x;
-static volatile int16_t mouse_y;
 
+// data stream coming from the mouse will be waiting inside this buffer
 static ringbuffer mouse_in;
 
+// called on each interrupt (keep it small) 
+// just pushes mouse data into the buffer
+uint32_t mouse_interrupt(uint32_t esp)
+{
+    if(!ringbuffer_put(&mouse_in,x86_inb(0x60)))kpanic("full");
+    return esp;
+}
+
+// process data in buffer (return true if anything was processed)
 bool mouse_worker()
 {
     if(ringbuffer_full(&mouse_in))
     {
-        klog("mouse buffer full");
+        kpanic("mouse buffer full"); // heavy debugging
     }
 
     bool wake=false;
@@ -32,7 +43,7 @@ bool mouse_worker()
     return wake;
 }
 
-
+//
 void mouse_wait(uint8_t a_type) //unsigned char
 {
   uint32_t _time_out=100000; //unsigned int
@@ -79,11 +90,6 @@ static void mouse_write(uint8_t  a_write)
   x86_outb(0x60, a_write);
 }
 
-uint32_t mouse_interrupt(uint32_t esp)
-{
-    if(!ringbuffer_put(&mouse_in,x86_inb(0x60)))kpanic("full");
-    return esp;
-}
 
 void mouse_init()
 {
@@ -117,44 +123,45 @@ void mouse_init()
   interrupt_register(INTERRUPT_MOUSE,&mouse_interrupt);
 }
 
-// called as we filled the 3 bytes, everytime.
+// called every time after the 3 bytes have been filled.
 void mouse_action()
 {
-    //klog("mouse %02x / %02x / %02x ",mouse_byte[0], mouse_byte[1],mouse_byte[2]);
-    //TODO: ignore last packet for 4packets mouse and resync if you get out of sync
-    
-    if(mouse_byte[0]&0x80||mouse_byte[0]&0x40)
+    /*     3rd byte bits have this meaning:
+     *
+     * key 0    left button         1
+     * key 1    right button        2
+     * key 2    middle button       4
+     * key 3    always one!         8
+     *
+     * key 4    x-axis sign bit    16 
+     * key 5    y-axis sign bit    32
+     *
+     * key 6    x-axis overflow    64
+     * key 7    y-axis overflow   128
+     */
+
+    int rel_x=0;
+    int rel_y=0;
+
+    /* ignore overflows? or assume max? */
+
+    if(mouse_byte[0]&0x80)
     {
-      //  klog("mouse overflow, skipping packet");
-        return; //skip packet on overflow
+        return;
+ //       klog("x overflow");
     }
 
-    //OOOMG!!//
-    if(mouse_byte[1]>127){
-	mouse_x-=256;
-	mouse_x+=mouse_byte[1];
-    }
-    else
+    if(mouse_byte[0]&0x40)
     {
-	mouse_x+=mouse_byte[1];
+        return;
+  //      klog("y overflow");
     }
 
-    if(mouse_byte[2]>127){
-	mouse_y-=256;
-	mouse_y+=mouse_byte[2];
-    }
-    else
-    {
-        mouse_y+=mouse_byte[2];
-    }
+    rel_x = mouse_byte[1] - ((mouse_byte[0] << 4) & 0x100);
+    rel_y = mouse_byte[2] - ((mouse_byte[0] << 3) & 0x100);
     
-    if(mouse_x<0)mouse_x=0;
-    if(mouse_y<0)mouse_y=0;
-
-    if(mouse_x>=1920)mouse_x=1920-1;
-    if(mouse_y>=1080)mouse_y=1080-1;
-
-    compositor_mouse_handle(mouse_x,1080-mouse_y-1, mouse_byte[0]);
+    // we pass the state through
+    compositor_mouse_handle(rel_x,-rel_y,mouse_byte[0]);
 }
 
 void mouse_handler(uint8_t byte)//struct regs *a_r) //struct regs *a_r (not used but just there)
@@ -166,12 +173,14 @@ void mouse_handler(uint8_t byte)//struct regs *a_r) //struct regs *a_r (not used
     case 0:
       mouse_byte[0]=byte;
       mouse_cycle++;
-        if(!(mouse_byte[0]&0x8))
-        {
-            //klog("mouse out of sync, try resync");
-            mouse_cycle--;
-    //        kpanic("mouse packets out of sync!?"); // this bit is always 1, otherwise panic!
-        }
+
+    // this bit is ALWAYS one, otherwise we are out of sync!
+    if(!(mouse_byte[0]&0x8))
+    {
+//        klog("mouse out of sync (try next packet) ...");
+        mouse_cycle--;
+    }
+
       break;
     case 1:
       mouse_byte[1]=byte;