/*-
 * Copyright (c) 2015 Tycho Nightingale <tycho.nightingale@pluribusnetworks.com>
 * Copyright (c) 2015 Nahanni Systems Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
#include <pthread.h>

#include "types.h"
#include "atkbdc.h"
#include "console.h"
#include "log.h"

/* keyboard device commands */
#define	PS2KC_RESET_DEV		0xff
#define	PS2KC_DISABLE		0xf5
#define	PS2KC_ENABLE		0xf4
#define	PS2KC_SET_TYPEMATIC	0xf3
#define	PS2KC_SEND_DEV_ID	0xf2
#define	PS2KC_SET_SCANCODE_SET	0xf0
#define	PS2KC_ECHO		0xee
#define	PS2KC_SET_LEDS		0xed

#define	PS2KC_BAT_SUCCESS	0xaa
#define	PS2KC_ACK		0xfa

#define	PS2KBD_FIFOSZ		16

struct fifo {
	uint8_t	buf[PS2KBD_FIFOSZ];
	int	rindex;		/* index to read from */
	int	windex;		/* index to write to */
	int	num;		/* number of bytes in the fifo */
	int	size;		/* size of the fifo */
};

struct ps2kbd_info {
	struct atkbdc_base	*base;
	pthread_mutex_t		mtx;

	bool			enabled;
	struct fifo		fifo;

	uint8_t			curcmd;	/* current command for next byte */
};

static void
fifo_init(struct ps2kbd_info *kbd)
{
	struct fifo *fifo;

	fifo = &kbd->fifo;
	fifo->size = sizeof(((struct fifo *)0)->buf);
}

static void
fifo_reset(struct ps2kbd_info *kbd)
{
	struct fifo *fifo;

	fifo = &kbd->fifo;
	bzero(fifo, sizeof(struct fifo));
	fifo->size = sizeof(((struct fifo *)0)->buf);
}

static void
fifo_put(struct ps2kbd_info *kbd, uint8_t val)
{
	struct fifo *fifo;

	fifo = &kbd->fifo;
	if (fifo->num < fifo->size) {
		fifo->buf[fifo->windex] = val;
		fifo->windex = (fifo->windex + 1) % fifo->size;
		fifo->num++;
	}
}

static int
fifo_get(struct ps2kbd_info *kbd, uint8_t *val)
{
	struct fifo *fifo;

	fifo = &kbd->fifo;
	if (fifo->num > 0) {
		*val = fifo->buf[fifo->rindex];
		fifo->rindex = (fifo->rindex + 1) % fifo->size;
		fifo->num--;
		return 0;
	}

	return -1;
}

int
ps2kbd_read(struct ps2kbd_info *kbd, uint8_t *val)
{
	int retval;

	pthread_mutex_lock(&kbd->mtx);
	retval = fifo_get(kbd, val);
	pthread_mutex_unlock(&kbd->mtx);

	return retval;
}

void
ps2kbd_write(struct ps2kbd_info *kbd, uint8_t val)
{
	pthread_mutex_lock(&kbd->mtx);
	if (kbd->curcmd) {
		switch (kbd->curcmd) {
		case PS2KC_SET_TYPEMATIC:
			fifo_put(kbd, PS2KC_ACK);
			break;
		case PS2KC_SET_SCANCODE_SET:
			fifo_put(kbd, PS2KC_ACK);
			break;
		case PS2KC_SET_LEDS:
			fifo_put(kbd, PS2KC_ACK);
			break;
		default:
			pr_err("Unhandled ps2 keyboard current "
			    "command byte 0x%02x\n", val);
			break;
		}
		kbd->curcmd = 0;
	} else {
		switch (val) {
		case 0x00:
			fifo_put(kbd, PS2KC_ACK);
			break;
		case PS2KC_RESET_DEV:
			fifo_reset(kbd);
			fifo_put(kbd, PS2KC_ACK);
			fifo_put(kbd, PS2KC_BAT_SUCCESS);
			break;
		case PS2KC_DISABLE:
			kbd->enabled = false;
			fifo_put(kbd, PS2KC_ACK);
			break;
		case PS2KC_ENABLE:
			kbd->enabled = true;
			fifo_reset(kbd);
			fifo_put(kbd, PS2KC_ACK);
			break;
		case PS2KC_SET_TYPEMATIC:
			kbd->curcmd = val;
			fifo_put(kbd, PS2KC_ACK);
			break;
		case PS2KC_SEND_DEV_ID:
			fifo_put(kbd, PS2KC_ACK);
			fifo_put(kbd, 0xab);
			fifo_put(kbd, 0x83);
			break;
		case PS2KC_SET_SCANCODE_SET:
			kbd->curcmd = val;
			fifo_put(kbd, PS2KC_ACK);
			break;
		case PS2KC_ECHO:
			fifo_put(kbd, PS2KC_ECHO);
			break;
		case PS2KC_SET_LEDS:
			kbd->curcmd = val;
			fifo_put(kbd, PS2KC_ACK);
			break;
		default:
			pr_err("Unhandled ps2 keyboard command "
			    "0x%02x\n", val);
			break;
		}
	}
	pthread_mutex_unlock(&kbd->mtx);
}

/*
 * Translate keysym to type 2 scancode and insert into keyboard buffer.
 */
static void
ps2kbd_keysym_queue(struct ps2kbd_info *kbd,
		    int down, uint32_t keysym)
{
	/* ASCII to type 2 scancode lookup table */
	const uint8_t translation[128] = {
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x29, 0x16, 0x52, 0x26, 0x25, 0x2e, 0x3d, 0x52,
		0x46, 0x45, 0x3e, 0x55, 0x41, 0x4e, 0x49, 0x4a,
		0x45, 0x16, 0x1e, 0x26, 0x25, 0x2e, 0x36, 0x3d,
		0x3e, 0x46, 0x4c, 0x4c, 0x41, 0x55, 0x49, 0x4a,
		0x1e, 0x1c, 0x32, 0x21, 0x23, 0x24, 0x2b, 0x34,
		0x33, 0x43, 0x3b, 0x42, 0x4b, 0x3a, 0x31, 0x44,
		0x4d, 0x15, 0x2d, 0x1b, 0x2c, 0x3c, 0x2a, 0x1d,
		0x22, 0x35, 0x1a, 0x54, 0x5d, 0x5b, 0x36, 0x4e,
		0x0e, 0x1c, 0x32, 0x21, 0x23, 0x24, 0x2b, 0x34,
		0x33, 0x43, 0x3b, 0x42, 0x4b, 0x3a, 0x31, 0x44,
		0x4d, 0x15, 0x2d, 0x1b, 0x2c, 0x3c, 0x2a, 0x1d,
		0x22, 0x35, 0x1a, 0x54, 0x5d, 0x5b, 0x0e, 0x00,
	};

	switch (keysym) {
	case 0x0 ... 0x7f:
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, translation[keysym]);
		break;
	case 0xff08:	/* Back space */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x66);
		break;
	case 0xff09:	/* Tab */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x0d);
		break;
	case 0xff0d:	/* Return  */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x5a);
		break;
	case 0xff1b:	/* Escape */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x76);
		break;
	case 0xff50:	/* Home */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x6c);
		break;
	case 0xff51:	/* Left arrow */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x6b);
		break;
	case 0xff52:	/* Up arrow */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x75);
		break;
	case 0xff53:	/* Right arrow */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x74);
		break;
	case 0xff54:	/* Down arrow */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x72);
		break;
	case 0xff55:	/* PgUp */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x7d);
		break;
	case 0xff56:	/* PgDwn */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x7a);
		break;
	case 0xff57:	/* End */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x69);
		break;
	case 0xff63:	/* Ins */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x70);
		break;
	case 0xff8d:	/* Keypad Enter */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x5a);
		break;
	case 0xffe1:	/* Left shift */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x12);
		break;
	case 0xffe2:	/* Right shift */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x59);
		break;
	case 0xffe3:	/* Left control */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x14);
		break;
	case 0xffe4:	/* Right control */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x14);
		break;
	case 0xffe7:	/* Left meta */
		/* XXX */
		break;
	case 0xffe8:	/* Right meta */
		/* XXX */
		break;
	case 0xffe9:	/* Left alt */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x11);
		break;
	case 0xfe03:	/* AltGr */
	case 0xffea:	/* Right alt */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x11);
		break;
	case 0xffeb:	/* Left Windows */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x1f);
		break;
	case 0xffec:	/* Right Windows */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x27);
		break;
	case 0xffbe:    /* F1 */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x05);
		break;
	case 0xffbf:    /* F2 */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x06);
		break;
	case 0xffc0:    /* F3 */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x04);
		break;
	case 0xffc1:    /* F4 */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x0C);
		break;
	case 0xffc2:    /* F5 */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x03);
		break;
	case 0xffc3:    /* F6 */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x0B);
		break;
	case 0xffc4:    /* F7 */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x83);
		break;
	case 0xffc5:    /* F8 */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x0A);
		break;
	case 0xffc6:    /* F9 */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x01);
		break;
	case 0xffc7:    /* F10 */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x09);
		break;
	case 0xffc8:    /* F11 */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x78);
		break;
	case 0xffc9:    /* F12 */
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x07);
		break;
	case 0xffff:    /* Del */
		fifo_put(kbd, 0xe0);
		if (!down)
			fifo_put(kbd, 0xf0);
		fifo_put(kbd, 0x71);
		break;
	default:
		pr_err("Unhandled ps2 keyboard keysym 0x%x\n",
		     keysym);
		break;
	}
}

static void
ps2kbd_event(int down, uint32_t keysym, void *arg)
{
	struct ps2kbd_info *kbd = arg;
	int fifo_full;

	pthread_mutex_lock(&kbd->mtx);
	if (!kbd->enabled) {
		pthread_mutex_unlock(&kbd->mtx);
		return;
	}
	fifo_full = kbd->fifo.num == PS2KBD_FIFOSZ;
	ps2kbd_keysym_queue(kbd, down, keysym);
	pthread_mutex_unlock(&kbd->mtx);

	if (!fifo_full)
		atkbdc_event(kbd->base, 1);
}

struct ps2kbd_info *
ps2kbd_init(struct atkbdc_base *base)
{
	struct ps2kbd_info *kbd;

	kbd = calloc(1, sizeof(struct ps2kbd_info));
	if (!kbd) {
		pr_err("%s: alloc memory fail!\n", __func__);
		return NULL;
	}

	pthread_mutex_init(&kbd->mtx, NULL);
	fifo_init(kbd);
	kbd->base = base;

	console_kbd_register(ps2kbd_event, kbd, 1);

	return kbd;
}

void
ps2kbd_deinit(struct atkbdc_base *base)
{
	console_kbd_unregister();
	free(base->ps2kbd);
	base->ps2kbd = NULL;
}