Move PS/2 driver to userspace

drivers/ps2d/src/mouse.rs

@@ -0,0 +1,73 @@
+use std::fs::File;
+use std::io::{Read, Write};
+use std::mem;
+use std::thread;
+
+bitflags! {
+    flags MousePacketFlags: u8 {
+        const LEFT_BUTTON = 1,
+        const RIGHT_BUTTON = 1 << 1,
+        const MIDDLE_BUTTON = 1 << 2,
+        const ALWAYS_ON = 1 << 3,
+        const X_SIGN = 1 << 4,
+        const Y_SIGN = 1 << 5,
+        const X_OVERFLOW = 1 << 6,
+        const Y_OVERFLOW = 1 << 7
+    }
+}
+
+pub fn mouse(extra_packet: bool) {
+    let mut file = File::open("irq:12").expect("ps2d: failed to open irq:12");
+
+    let mut packets = [0; 4];
+    let mut packet_i = 0;
+    loop {
+        let mut irqs = [0; 8];
+        if file.read(&mut irqs).expect("ps2d: failed to read irq:12") >= mem::size_of::<usize>() {
+            let data: u8;
+            unsafe {
+                asm!("in al, dx" : "={al}"(data) : "{dx}"(0x60) : : "intel", "volatile");
+            }
+
+            packets[packet_i] = data;
+            packet_i += 1;
+
+            let flags = MousePacketFlags::from_bits_truncate(packets[0]);
+            if ! flags.contains(ALWAYS_ON) {
+                println!("MOUSE MISALIGN {:X}", packets[0]);
+
+                packets = [0; 4];
+                packet_i = 0;
+            } else if packet_i >= packets.len() || (!extra_packet && packet_i >= 3) {
+                if ! flags.contains(X_OVERFLOW) && ! flags.contains(Y_OVERFLOW) {
+                    let mut dx = packets[1] as isize;
+                    if flags.contains(X_SIGN) {
+                        dx -= 0x100;
+                    }
+
+                    let mut dy = packets[2] as isize;
+                    if flags.contains(Y_SIGN) {
+                        dy -= 0x100;
+                    }
+
+                    let extra = if extra_packet {
+                        packets[3]
+                    } else {
+                        0
+                    };
+
+                    print!("ps2d: IRQ {:?}, {}, {}, {}\n", flags, dx, dy, extra);
+                } else {
+                    println!("ps2d: overflow {:X} {:X} {:X} {:X}", packets[0], packets[1], packets[2], packets[3]);
+                }
+
+                packets = [0; 4];
+                packet_i = 0;
+            }
+
+            file.write(&irqs).expect("ps2d: failed to write irq:12");
+        } else {
+            thread::yield_now();
+        }
+    }
+}