/*
 *   Wi-Fi Detector opensource firmware
 *   LCD support
 *
 *   Copyright (C) 2007 Michael Buesch <mb@bu3sch.de>
 *
 *   This program is free software; you can redistribute it and/or
 *   modify it under the terms of the GNU General Public License
 *   as published by the Free Software Foundation; either version 2
 *   of the License, or (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 */

#include "lcd.h"
#include "main.h"
#include "util.h"
#include "font.h"

#include <stdint.h>
#include <string.h>
#include <avr/io.h>


/* LCD hardware definitions */
#define LCD_PORT	PORTC
#define LCD_DDR		DDRC
#define LCD_CLK		(1 << 0)	/* clock */
#define LCD_DTA		(1 << 1)	/* data */
#define LCD_RS		(1 << 2)	/* register select */
#define LCD_CS		(1 << 3)	/* chip select */
#define LCD_RST		(1 << 4)	/* reset */
#define LCD_BACKL_PORT	PORTD	/* Backlight */
#define LCD_BACKL_DDR	DDRD
#define LCD_BACKLIGHT	(1 << 4)

/* LCD commands */
#define LCD_CMD_LINE(nr)	(0xB0 + (nr))

/* The LCD data buffer */
uint8_t lcd_buffer[LCD_BUFFER_SIZE];
uint16_t lcd_cursor;


static void lcd_write(uint8_t data)
{
	uint8_t i = 8;

	LCD_PORT |= LCD_DTA;
	LCD_PORT |= LCD_CLK;
	LCD_PORT &= ~LCD_CS;
	do {
		if (data & 0x80)
			LCD_PORT |= LCD_DTA;
		else
			LCD_PORT &= ~LCD_DTA;
		LCD_PORT &= ~LCD_CLK;
		LCD_PORT |= LCD_CLK;
		udelay(1);
		LCD_PORT &= ~LCD_CLK;
		data <<= 1;
	} while (--i);
	LCD_PORT |= LCD_CS;
}

static void lcd_command(uint8_t command)
{
	LCD_PORT &= ~LCD_RS;
	lcd_write(command);
}

static void lcd_data(uint8_t data)
{
	LCD_PORT |= LCD_RS;
	lcd_write(data);
}

void lcd_clear_buffer(void)
{
	memset(lcd_buffer, 0, LCD_BUFFER_SIZE);
	lcd_cursor = 0;
}

void lcd_commit(void)
{
	uint8_t i, j;
	uint8_t *d;

	for (i = 0; i < 4; i++) {
		lcd_command(LCD_CMD_LINE(i));
		d = &lcd_buffer[i * LCD_NR_COLUMNS];
		lcd_command(0x12);
		lcd_command(0x04);
		for (j = 0; j < LCD_NR_COLUMNS; j++)
			lcd_data(d[j]);
	}
}

void lcd_char_out(uint8_t c)
{
	uint8_t pixel_col;
	uint8_t i;
	uint16_t cursor;

	for (i = 0; i < LCD_PIXCOLS_PER_CHAR; i++) {
		pixel_col = pgm_read_byte(&font_table[c][i]);
		cursor = lcd_cursor;
		lcd_buffer[cursor] = pixel_col;
		if (cursor == LCD_BUFFER_SIZE - 1)
			lcd_cursor = 0;
		else
			lcd_cursor++;
	}
}

void printmem(const char *string, uint8_t length)
{
	uint8_t c, i;

	for (i = 0; i < length; i++) {
		c = string[i];
		lcd_char_out(c);
	}
}

void printee(const eeprom_char *eeprom_string)
{
	uint8_t c;
	const eeprom_uint8_t *p = (const eeprom_uint8_t *)eeprom_string;

	for ( ; ; p++) {
		c = eeprom_read8(p);
		if (c == '\0')
			break;
		lcd_char_out(c);
	}
}

void print(const prog_char *flash_string)
{
	uint8_t c;

	for ( ; ; flash_string++) {
		c = pgm_read_byte(flash_string);
		if (c == '\0')
			break;
		lcd_char_out(c);
	}
}

void printhex(uint8_t number)
{
	lcd_char_out(hexdigit_to_ascii((number & 0xF0) >> 4));
	lcd_char_out(hexdigit_to_ascii(number & 0x0F));
}

void printdec(uint16_t number)
{
	uint8_t num[NUM16_NR_DIGITS + 1];
	uint8_t i, c;

	num16_to_ascii(num, number);
	for (i = 0; i < ARRAY_SIZE(num); i++) {
		c = num[i];
		if (c == '\0')
			break;
		lcd_char_out(c);
	}
}

void lcd_backlight_on(void)
{
	/* This is called from IRQ and non-IRQ context,
	 * so we must make sure this is atomic. */
	LCD_BACKL_PORT |= LCD_BACKLIGHT;
}

void lcd_backlight_off(void)
{
	/* This is called from IRQ and non-IRQ context,
	 * so we must make sure this is atomic. */
	LCD_BACKL_PORT &= ~LCD_BACKLIGHT;
}

void lcd_init(void)
{
	LCD_BACKL_DDR |= LCD_BACKLIGHT;
	lcd_backlight_off();
	LCD_DDR |= LCD_CLK | LCD_DTA | LCD_RS |
		    LCD_CS | LCD_RST;
	LCD_PORT |= (LCD_CS | LCD_CLK |
		     LCD_DTA | LCD_RS);
	/* Reset the LCD module */
	LCD_PORT &= ~LCD_RST;
	mdelay(100);
	LCD_PORT |= LCD_RST;
	mdelay(50);
	/* Initialize it */
	lcd_command(0xE2);
	lcd_command(0xAB);
	lcd_command(0xC8);
	lcd_command(0x40);
	lcd_command(LCD_CMD_LINE(0));
	lcd_command(0x10);
	lcd_command(0x00);
	lcd_command(0xA1);
	lcd_command(0xA6);
	lcd_command(0xA2);
	lcd_command(0x2F);
	lcd_command(0x24);
	lcd_command(0x81);
	lcd_command(0x00);
	lcd_clear_buffer();
	lcd_commit();
	lcd_command(0xAF);
}