add ps2_keyboard driver

5 files changed, 48 insertions, 3 deletions

diff --git a/devices/Makefile b/devices/Makefile
index 41edaaa..0e07a83 100644
--- a/devices/Makefile
+++ b/devices/Makefile
@@ -1,10 +1,10 @@
 include ../${ARCH}/toolchain.mk
 
-CCFLAGS += -I. -I../${ARCH}
+CCFLAGS += -I. -I../${ARCH} -I../lib
 
 all: devs.a
 
-devs,SRCS = pic_8259.c uart_16550.c vga.c
+devs,SRCS = pic_8259.c uart_16550.c vga.c ps2_keyboard.c
 
 include ../rules.mk
 
diff --git a/devices/pic_8259.c b/devices/pic_8259.c
index 43b090f..74c576a 100644
--- a/devices/pic_8259.c
+++ b/devices/pic_8259.c
@@ -28,7 +28,7 @@ pic_init()
   outb(ICW4_8086, PIC2 + DATA);
 
   // PIC masks
-  outb(0xff, PIC1 + DATA);
+  outb(0xfc, PIC1 + DATA);
   outb(0xff, PIC2 + DATA);
 }
 
diff --git a/devices/ps2_keyboard.c b/devices/ps2_keyboard.c
new file mode 100644
index 0000000..6171d18
--- /dev/null
+++ b/devices/ps2_keyboard.c
@@ -0,0 +1,40 @@
+#include "ps2_keyboard.h"
+#include <stdint.h>
+#include <stdio.h>
+#include <sys/io.h>
+
+const uint8_t comm_port = 0x64; // r  status register
+                                //  w command register
+const uint8_t comm_enable_first_ps2 = 0xae;
+const uint8_t comm_read_ctrl_config = 0x20;
+const uint8_t comm_write_ctrl_config = 0x60;
+const uint8_t data_port = 0x60; // rw
+const uint8_t data_enable_scanning = 0xf4;
+
+const char scancodes[] = {'E', '1', '2', '3',  '4', '5', '6',  '7', '8', '9',  '0', '-', '=', '\b', 'T', 'q', 'w', 'e',
+                          'r', 't', 'y', 'u',  'i', 'o', 'p',  '[', ']', '\n', 'C', 'a', 's', 'd',  'f', 'g', 'h', 'j',
+                          'k', 'l', ';', '\'', '`', 'L', '\\', 'z', 'x', 'c',  'v', 'b', 'n', 'm',  ',', '.', '/', 'R'};
+
+void
+ps2_keyboard_init()
+{
+  // eat all previous keystrikes
+  while (inb(comm_port) & 0x1) inb(data_port);
+  outb(comm_port, comm_enable_first_ps2);
+  outb(comm_port, comm_read_ctrl_config);
+  const uint8_t conf = (inb(data_port) | 1) & ~0x10;
+  outb(comm_port, comm_write_ctrl_config);
+  outb(data_port, conf);
+  outb(data_port, data_enable_scanning);
+}
+
+void
+ps2_keyboard_irq_handler()
+{
+  const uint8_t key = inb(data_port);
+  if (key >= 0x80) return;
+
+  if (key < 0x37) printf("%c", scancodes[key - 1]);
+  else
+    printf("key pressed: %x\n", key);
+}
diff --git a/devices/ps2_keyboard.h b/devices/ps2_keyboard.h
new file mode 100644
index 0000000..5f4fcc2
--- /dev/null
+++ b/devices/ps2_keyboard.h
@@ -0,0 +1,4 @@
+#pragma once
+
+void ps2_keyboard_init();
+void ps2_keyboard_irq_handler();
diff --git a/devices/uart_16550.h b/devices/uart_16550.h
index d053985..0e181b2 100644
--- a/devices/uart_16550.h
+++ b/devices/uart_16550.h
@@ -53,4 +53,5 @@ enum UART {
 };
 
 int uart_init(enum UART port);
+void uart_write(enum UART port, char a);
 int uart_puts(enum UART port, const char *string, int length);