1 files changed, 28 insertions, 0 deletions
diff --git a/src/kernel/arch/i386/driver/ps2.c b/src/kernel/arch/i386/driver/ps2.c
new file mode 100644
index 0000000..1af3166
--- /dev/null
+++ b/src/kernel/arch/i386/driver/ps2.c
@@ -0,0 +1,28 @@
+#include <kernel/arch/i386/driver/ps2.h>
+#include <kernel/arch/i386/interrupts/irq.h>
+#include <shared/mem.h>
+
+#define BACKLOG_CAPACITY 16
+
+/* TODO move away from tty/ */
+
+static volatile uint8_t backlog[BACKLOG_CAPACITY] = {};
+static volatile size_t backlog_size = 0;
+
+void ps2_recv(uint8_t s) {
+	if (backlog_size >= BACKLOG_CAPACITY) return;
+	backlog[backlog_size++] = s;
+}
+
+size_t ps2_read(uint8_t *buf, size_t max_len) {
+	irq_interrupt_flag(true);
+	while (backlog_size == 0)
+		asm("hlt" ::: "memory");
+	irq_interrupt_flag(false);
+
+	size_t len = backlog_size;
+	if (len > max_len) len = max_len;
+	backlog_size = 0;
+	memcpy(buf, (void*)backlog, len);
+	return len;
+}