Merge branch 'fix_vmmouse' into 'master'

Fix and re-enable vmmouse support

Closes #39

See merge request redox-os/drivers!125

ps2d/src/state.rs

@@ -49,7 +49,7 @@ impl<F: Fn(u8,bool) -> char> Ps2d<F> {
         let extra_packet = ps2.init().expect("ps2d: failed to initialize");
 
         let vmmouse_relative = true;
-        let vmmouse = false; //vm::enable(vmmouse_relative);
+        let vmmouse = vm::enable(vmmouse_relative);
 
         let mut ps2d = Ps2d {
             ps2,

ps2d/src/vm.rs

@@ -9,6 +9,7 @@ use core::arch::global_asm;
 const MAGIC: u32 = 0x564D5868;
 const PORT: u16 = 0x5658;
 
+pub const GETVERSION: u32 = 10;
 pub const ABSPOINTER_DATA: u32 = 39;
 pub const ABSPOINTER_STATUS: u32 = 40;
 pub const ABSPOINTER_COMMAND: u32 = 41;
@@ -50,6 +51,8 @@ cmd_inner:
     mov DWORD PTR [rdi + 0x0C], edx
     mov DWORD PTR [rdi + 0x10], esi
     mov DWORD PTR [rdi + 0x14], r8d
+
+    ret
 ",
     MAGIC = const MAGIC,
     PORT = const PORT,
@@ -80,6 +83,12 @@ pub fn enable(relative: bool) -> bool {
     eprintln!("ps2d: Enable vmmouse");
 
     unsafe {
+        let (eax, ebx, _, _, _, _) = cmd(GETVERSION, 0);
+        if ebx != MAGIC || eax == 0xFFFFFFFF {
+            eprintln!("ps2d: No vmmouse support");
+            return false;
+        }
+
         let _ = cmd(ABSPOINTER_COMMAND, CMD_ENABLE);
 
         let (status, _, _, _, _, _) = cmd(ABSPOINTER_STATUS, 0);