path: root/firmware/drivers/button.c

/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Copyright (C) 2002 by Daniel Stenberg
 *
 * iPod driver based on code from the ipodlinux project - http://ipodlinux.org
 * Adapted for Rockbox in December 2005
 * Original file: linux/arch/armnommu/mach-ipod/keyboard.c
 * Copyright (c) 2003-2005 Bernard Leach (leachbj@bouncycastle.org)
 *
 *
 * All files in this archive are subject to the GNU General Public License.
 * See the file COPYING in the source tree root for full license agreement.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ****************************************************************************/

/*
 * Rockbox button functions
 */

#include <stdlib.h>
#include "config.h"
#include "cpu.h"
#include "system.h"
#include "button.h"
#include "kernel.h"
#include "backlight.h"
#include "adc.h"
#include "serial.h"
#include "power.h"
#include "system.h"
#include "powermgmt.h"

struct event_queue button_queue;

static long lastbtn;   /* Last valid button status */
static long last_read; /* Last button status, for debouncing/filtering */
#ifdef HAVE_LCD_BITMAP
static bool flipped;  /* buttons can be flipped to match the LCD flip */
#endif

/* how often we check to see if a button is pressed */
#define POLL_FREQUENCY    HZ/100

/* how long until repeat kicks in */
#define REPEAT_START      30

/* the speed repeat starts at */
#define REPEAT_INTERVAL_START   16

/* speed repeat finishes at */
#define REPEAT_INTERVAL_FINISH  5

/* the power-off button and number of repeated keys before shutting off */
#if (CONFIG_KEYPAD == IPOD_3G_PAD) || (CONFIG_KEYPAD == IPOD_4G_PAD) ||\
    (CONFIG_KEYPAD == IRIVER_IFP7XX_PAD)
#define POWEROFF_BUTTON BUTTON_PLAY
#define POWEROFF_COUNT 40
#else
#define POWEROFF_BUTTON BUTTON_OFF
#define POWEROFF_COUNT 10
#endif

static int button_read(void);

#if (CONFIG_KEYPAD == IRIVER_H100_PAD) || (CONFIG_KEYPAD == IRIVER_H300_PAD)
static bool remote_button_hold_only(void);
#endif

#if CONFIG_KEYPAD == IPOD_4G_PAD
/* Variable to use for setting button status in interrupt handler */
int int_btn = BUTTON_NONE;

static void opto_i2c_init(void)
{
    int i, curr_value;

    /* wait for value to settle */
    i = 1000;
    curr_value = (inl(0x7000c104) << 16) >> 24;
    while (i > 0)
    {
        int new_value = (inl(0x7000c104) << 16) >> 24;

        if (new_value != curr_value) {
            i = 10000;
            curr_value = new_value;
        }
        else {
            i--;
        }
    }

    GPIOB_OUTPUT_VAL |= 0x10;
    DEV_EN |= 0x10000;
    DEV_RS |= 0x10000;
    udelay(5);
    DEV_RS &= ~0x10000; /* finish reset */

    outl(0xffffffff, 0x7000c120);
    outl(0xffffffff, 0x7000c124);
    outl(0xc00a1f00, 0x7000c100);
    outl(0x1000000, 0x7000c104);
}

static int ipod_4g_button_read(void)
{
    unsigned reg, status;
    static int clickwheel_down = 0;
    static int old_wheel_value = -1;
    int wheel_keycode = BUTTON_NONE;
    int wheel_delta, wheel_delta_abs;
    int new_wheel_value;
    int btn = BUTTON_NONE;
    
    /* The ipodlinux source had a udelay(250) here, but testing has shown that
       it is not needed - tested on Nano, Color/Photo and Video. */
    /* udelay(250);*/

    reg = 0x7000c104;
    if ((inl(0x7000c104) & 0x4000000) != 0) {
        reg = reg + 0x3C;   /* 0x7000c140 */

        status = inl(0x7000c140);
        outl(0x0, 0x7000c140);  /* clear interrupt status? */

        if ((status & 0x800000ff) == 0x8000001a) {
            /* NB: highest wheel = 0x5F, clockwise increases */
            new_wheel_value = ((status << 9) >> 25) & 0xff;

            if (status & 0x100)
                btn |= BUTTON_SELECT;
            if (status & 0x200)
                btn |= BUTTON_RIGHT;
            if (status & 0x400)
                btn |= BUTTON_LEFT;
            if (status & 0x800)
                btn |= BUTTON_PLAY;
            if (status & 0x1000)
                btn |= BUTTON_MENU;
            if (status & 0x40000000) {
                /* scroll wheel down */
                clickwheel_down = 1;
                backlight_on();
                if (old_wheel_value != -1) {
                    wheel_delta = new_wheel_value - old_wheel_value;
                    wheel_delta_abs = wheel_delta < 0 ? -wheel_delta 
                                                      : wheel_delta;
                    
                    if (wheel_delta_abs > 48) {
                        if (old_wheel_value > new_wheel_value)
                            /* wrapped around the top going clockwise */
                            wheel_delta += 96;
                        else if (old_wheel_value < new_wheel_value)
                            /* wrapped around the top going counterclockwise */                             wheel_delta -= 96;
                    }
                    /* TODO: these thresholds should most definitely be
                       settings, and we're probably going to want a more
                       advanced scheme than this anyway. */
                    if (wheel_delta > 4) {
                        wheel_keycode = BUTTON_SCROLL_FWD;
                        old_wheel_value = new_wheel_value;
                    } else if (wheel_delta < -4) {
                        wheel_keycode = BUTTON_SCROLL_BACK;
                        old_wheel_value = new_wheel_value;
                    }

                    if (wheel_keycode != BUTTON_NONE) {
                        /* When you use the clickwheel, the queue should
                           usually have no other events in it, so we check if
                           it's empty to see whether pending clickwheel events
                           have been handled. This way, Rockbox will stop
                           responding to the clickwheel if it doesn't have time
                           to handle the events immediately.
                           Can also implement queue_peek() to do this in a
                           cleaner way.
                         */
                        if (queue_empty(&button_queue))
                            queue_post(&button_queue, wheel_keycode, NULL);
                    }
                }
                else {
                    old_wheel_value = new_wheel_value;
                }
            }
            else if (clickwheel_down) {
                /* scroll wheel up */
                old_wheel_value = -1;
                clickwheel_down = 0;
            }
        }
        /* 
       Don't know why this should be needed, let me know if you do. 
       else if ((status & 0x800000FF) == 0x8000003A) {
            wheel_value = status & 0x800000FF;
        }
        */
        else if (status == 0xffffffff) {
            opto_i2c_init();
        }
    }

    if ((inl(reg) & 0x8000000) != 0) {
        outl(0xffffffff, 0x7000c120);
        outl(0xffffffff, 0x7000c124);
    }
    return btn;
}

void ipod_4g_button_int(void)
{
    CPU_HI_INT_CLR = I2C_MASK;
    /* The following delay was 250 in the ipodlinux source, but 50 seems to 
       work fine - tested on Nano, Color/Photo and Video. */
    udelay(50); 
    outl(0x0, 0x7000c140); 
    int_btn = ipod_4g_button_read();
    outl(inl(0x7000c104) | 0xC000000, 0x7000c104);
    outl(0x400a1f00, 0x7000c100);

    GPIOB_OUTPUT_VAL |= 0x10;
    CPU_INT_EN = 0x40000000;
    CPU_HI_INT_EN = I2C_MASK;
}
#endif 
#if CONFIG_KEYPAD == IPOD_3G_PAD
/* Variable to use for setting button status in interrupt handler */
int int_btn = BUTTON_NONE;

/**
 * 
 * 
 */
void handle_scroll_wheel(int new_scroll, int was_hold, int reverse)
{
    int wheel_keycode = BUTTON_NONE;
    static int prev_scroll = -1;
    static int scroll_state[4][4] = {
        {0, 1, -1, 0},
        {-1, 0, 0, 1},
        {1, 0, 0, -1},
        {0, -1, 1, 0}
    };

    if ( prev_scroll == -1 ) {
        prev_scroll = new_scroll;
    }
    else if (!was_hold) {
        switch (scroll_state[prev_scroll][new_scroll]) {
        case 1:
            if (reverse) {
                /* 'r' keypress */
                wheel_keycode = BUTTON_SCROLL_FWD;
            }
            else {
                /* 'l' keypress */
                wheel_keycode = BUTTON_SCROLL_BACK;
            }
            break;
        case -1:
            if (reverse) {
                /* 'l' keypress */
                wheel_keycode = BUTTON_SCROLL_BACK;
            }
            else {
                /* 'r' keypress */
                wheel_keycode = BUTTON_SCROLL_FWD;
            break;
        default:
            /* only happens if we get out of sync */
            break;
        }
    }
    }
    if (wheel_keycode != BUTTON_NONE)
              queue_post(&button_queue, wheel_keycode, NULL);
    prev_scroll = new_scroll;
}

static int ipod_3g_button_read(void)
{
     unsigned char source, state;
    static int was_hold = 0;
int btn = BUTTON_NONE;
    /*
     * we need some delay for g3, cause hold generates several interrupts,
     * some of them delayed
     */
        udelay(250);

    /* get source of interupts */
    source = inb(0xcf000040);
    if (source) {
        
        /* get current keypad status */
        state = inb(0xcf000030);
        outb(~state, 0xcf000060);
    
            if (was_hold && source == 0x40 && state == 0xbf) {
                /* ack any active interrupts */
                outb(source, 0xcf000070);
                return BUTTON_NONE;
            }
            was_hold = 0;
    
    
        if ( source & 0x20 ) {
                /* 3g hold switch is active low */
                    btn |= BUTTON_HOLD;
                    was_hold = 1;
                /* hold switch on 3g causes all outputs to go low */
                /* we shouldn't interpret these as key presses */
                goto done;
        }
        if (source & 0x1) {
             btn |= BUTTON_RIGHT;
        }
        if (source & 0x2) {
            btn |= BUTTON_SELECT;
        }
        if (source & 0x4) {
            btn |= BUTTON_PLAY;
        }
        if (source & 0x8) {
            btn |= BUTTON_LEFT;
        }
        if (source & 0x10) {
            btn |= BUTTON_MENU;
        }
    
        if (source & 0xc0) {
            handle_scroll_wheel((state & 0xc0) >> 6, was_hold, 0);
        }
    done:
    
        /* ack any active interrupts */
        outb(source, 0xcf000070);
    }
    return btn;
}

void ipod_3g_button_int(void)
{
    /**
     *  Theire is other things to do but for now ...
     * TODO: implement this function in a better way 
     **/
   int_btn = ipod_3g_button_read();
   
}
#endif 
static void button_tick(void)
{
    static int tick = 0;
    static int count = 0;
    static int repeat_speed = REPEAT_INTERVAL_START;
    static int repeat_count = 0;
    static bool repeat = false;
    static bool post = false;
    int diff;
    int btn;

#if (CONFIG_KEYPAD == PLAYER_PAD) || (CONFIG_KEYPAD == RECORDER_PAD)

    /* Post events for the remote control */
    btn = remote_control_rx();
    if(btn)
    {
        queue_post(&button_queue, btn, NULL);
    }
#endif

    /* only poll every X ticks */
    if ( ++tick >= POLL_FREQUENCY )
    {
        btn = button_read();

        /* Find out if a key has been released */
        diff = btn ^ lastbtn;
        if(diff && (btn & diff) == 0)
        {
            queue_post(&button_queue, BUTTON_REL | diff, NULL);
        }
        else
        {
            if ( btn )
            {
                /* normal keypress */
                if ( btn != lastbtn )
                {
                    post = true;
                    repeat = false;
                    repeat_speed = REPEAT_INTERVAL_START;

                }
                else /* repeat? */
                {
                    if ( repeat )
                    {
                        if (!post)
                            count--;
                        if (count == 0) {
                            post = true;
                            /* yes we have repeat */
                            repeat_speed--;
                            if (repeat_speed < REPEAT_INTERVAL_FINISH)
                                repeat_speed = REPEAT_INTERVAL_FINISH;
                            count = repeat_speed;

                            repeat_count++;

                            /* Send a SYS_POWEROFF event if we have a device
                               which doesn't shut down easily with the OFF
                               key */
#ifdef HAVE_SW_POWEROFF
#ifdef BUTTON_RC_STOP
                            if ((btn == POWEROFF_BUTTON || btn == BUTTON_RC_STOP) &&
#else
                            if (btn == POWEROFF_BUTTON &&
#endif
#if defined(HAVE_CHARGING) && !defined(HAVE_POWEROFF_WHILE_CHARGING)
                                !charger_inserted() &&
#endif
                                repeat_count > POWEROFF_COUNT)
                            {
                                /* Tell the main thread that it's time to
                                   power off */
                                sys_poweroff();

                                /* Safety net for players without hardware
                                   poweroff */
                                if(repeat_count > POWEROFF_COUNT * 10)
                                    power_off();
                            }
#endif
                        }
                    }
                    else
                    {
                        if (count++ > REPEAT_START)
                        {
                            post = true;
                            repeat = true;
                            repeat_count = 0;
                            /* initial repeat */
                            count = REPEAT_INTERVAL_START;
                        }
                    }
                }
                if ( post )
                {
                    if (repeat)
                    {
                        if (queue_empty(&button_queue))
                        {
                            queue_post(&button_queue, BUTTON_REPEAT | btn, NULL);
                            post = false;
                        }
                    }
                    else
                    {
                        queue_post(&button_queue, btn, NULL);
                        post = false;
                    }
#ifdef HAVE_REMOTE_LCD
                    if(btn & BUTTON_REMOTE)
                        remote_backlight_on();
                    else
#endif
                        backlight_on();

                    reset_poweroff_timer();
                }
            }
            else
            {
                repeat = false;
                count = 0;
            }
        }
        lastbtn = btn & ~(BUTTON_REL | BUTTON_REPEAT);
        tick = 0;
    }
}

long button_get(bool block)
{
    struct event ev;

    if ( block || !queue_empty(&button_queue) )
    {
        queue_wait(&button_queue, &ev);
        return ev.id;
    }
    return BUTTON_NONE;
}

long button_get_w_tmo(int ticks)
{
    struct event ev;
    queue_wait_w_tmo(&button_queue, &ev, ticks);
    return (ev.id != SYS_TIMEOUT)? ev.id: BUTTON_NONE;
}

void button_init(void)
{
    /* hardware inits */
#if CONFIG_KEYPAD == IRIVER_H100_PAD
    /* Set GPIO33, GPIO37, GPIO38  and GPIO52 as general purpose inputs */
    GPIO1_FUNCTION |= 0x00100062;
    GPIO1_ENABLE &= ~0x00100060;
#elif CONFIG_KEYPAD == IRIVER_H300_PAD
    /* Set GPIO9 and GPIO15 as general purpose inputs */
    GPIO_ENABLE &= ~0x00008200;
    GPIO_FUNCTION |= 0x00008200;
    /* Set GPIO33, GPIO37, GPIO38  and GPIO52 as general purpose inputs */
    GPIO1_ENABLE &= ~0x00100060;
    GPIO1_FUNCTION |= 0x00100062;
#elif CONFIG_KEYPAD == RECORDER_PAD
    /* Set PB4 and PB8 as input pins */
    PBCR1 &= 0xfffc;  /* PB8MD = 00 */
    PBCR2 &= 0xfcff;  /* PB4MD = 00 */
    PBIOR &= ~0x0110; /* Inputs */
#elif CONFIG_KEYPAD == PLAYER_PAD
    /* set PA5 and PA11 as input pins */
    PACR1 &= 0xff3f;  /* PA11MD = 00 */
    PACR2 &= 0xfbff;  /* PA5MD = 0 */
    PAIOR &= ~0x0820; /* Inputs */
#elif CONFIG_KEYPAD == ONDIO_PAD
    /* nothing to initialize here */
#elif CONFIG_KEYPAD == GMINI100_PAD
    /* nothing to initialize here */
#elif CONFIG_KEYPAD == IPOD_4G_PAD
    opto_i2c_init();
    /* hold button - enable as input */
    GPIOA_ENABLE |= 0x20;
    GPIOA_OUTPUT_EN &= ~0x20; 
    /* hold button - set interrupt levels */
    GPIOA_INT_LEV = ~(GPIOA_INPUT_VAL & 0x20);
    GPIOA_INT_CLR = GPIOA_INT_STAT & 0x20;
    /* enable interrupts */
    GPIOA_INT_EN = 0x20;
    CPU_INT_EN = 0x40000000;
    CPU_HI_INT_EN = I2C_MASK;

#elif CONFIG_KEYPAD == IPOD_3G_PAD
    outb(~inb(GPIOA_INPUT_VAL), GPIOA_INT_LEV);
    outb(inb(GPIOA_INT_STAT), GPIOA_INT_CLR);
    outb(0xff, GPIOA_INT_EN);

#endif /* CONFIG_KEYPAD */
    queue_init(&button_queue);
    button_read();
    lastbtn = button_read();
    tick_add_task(button_tick);
    reset_poweroff_timer();

#ifdef HAVE_LCD_BITMAP
    flipped = false;
#endif
}

#ifdef HAVE_LCD_BITMAP /* only bitmap displays can be flipped */
#if (CONFIG_KEYPAD != IPOD_3G_PAD) && (CONFIG_KEYPAD != IPOD_4G_PAD)
/*
 * helper function to swap UP/DOWN, LEFT/RIGHT (and F1/F3 for Recorder)
 */
static int button_flip(int button)
{
    int newbutton;

    newbutton = button &
        ~(BUTTON_UP | BUTTON_DOWN
        | BUTTON_LEFT | BUTTON_RIGHT
#if CONFIG_KEYPAD == RECORDER_PAD
        | BUTTON_F1 | BUTTON_F3
#endif
        );

    if (button & BUTTON_UP)
        newbutton |= BUTTON_DOWN;
    if (button & BUTTON_DOWN)
        newbutton |= BUTTON_UP;
    if (button & BUTTON_LEFT)
        newbutton |= BUTTON_RIGHT;
    if (button & BUTTON_RIGHT)
        newbutton |= BUTTON_LEFT;
#if CONFIG_KEYPAD == RECORDER_PAD
    if (button & BUTTON_F1)
        newbutton |= BUTTON_F3;
    if (button & BUTTON_F3)
        newbutton |= BUTTON_F1;
#endif

    return newbutton;
}
#else
/* We don't flip the iPod's keypad yet*/
#define button_flip(x) (x)
#endif

/*
 * set the flip attribute
 * better only call this when the queue is empty
 */
void button_set_flip(bool flip)
{
    if (flip != flipped) /* not the current setting */
    {
        /* avoid race condition with the button_tick() */
        int oldlevel = set_irq_level(HIGHEST_IRQ_LEVEL);
        lastbtn = button_flip(lastbtn);
        flipped = flip;
        set_irq_level(oldlevel);
    }
}
#endif /* HAVE_LCD_BITMAP */

/*
 Archos hardware button hookup
 =============================

 Recorder / Recorder FM/V2
 -------------------------
 F1, F2, F3, UP:           connected to AN4 through a resistor network
 DOWN, PLAY, LEFT, RIGHT:  likewise connected to AN5

 The voltage on AN4/ AN5 depends on which keys (or key combo) is pressed
 FM/V2 has PLAY and RIGHT switched compared to plain recorder

 ON:     PB8, low active (plain recorder) / AN3, low active (fm/v2)
 OFF:    PB4, low active (plain recorder) / AN2, high active (fm/v2)

 Player
 ------
 LEFT:   AN0
 MENU:   AN1
 RIGHT:  AN2
 PLAY:   AN3

 STOP:   PA11
 ON:     PA5

 All buttons are low active

 Ondio
 -----
 LEFT, RIGHT, UP, DOWN:    connected to AN4 through a resistor network

 The voltage on AN4 depends on which keys (or key combo) is pressed

 OPTION: AN2, high active (assigned as MENU)
 ON/OFF: AN3, low active (assigned as OFF)

*/

#if CONFIG_KEYPAD == RECORDER_PAD

#ifdef HAVE_FMADC
/* FM Recorder super-special levels */
#define LEVEL1        150
#define LEVEL2        385
#define LEVEL3        545
#define LEVEL4        700
#define ROW2_BUTTON1  BUTTON_PLAY
#define ROW2_BUTTON3  BUTTON_RIGHT

#else
/* plain bog standard Recorder levels */
#define LEVEL1        250
#define LEVEL2        500
#define LEVEL3        700
#define LEVEL4        900
#define ROW2_BUTTON1  BUTTON_RIGHT
#define ROW2_BUTTON3  BUTTON_PLAY
#endif /* HAVE_FMADC */

#elif CONFIG_KEYPAD == ONDIO_PAD
/* Ondio levels */
#define LEVEL1        165
#define LEVEL2        415
#define LEVEL3        585
#define LEVEL4        755

#endif /* CONFIG_KEYPAD */

/*
 * Get button pressed from hardware
 */
static int button_read(void)
{
    int btn = BUTTON_NONE;
    int retval;

    int data;

#if CONFIG_KEYPAD == IRIVER_H100_PAD

    static bool hold_button = false;
    static bool remote_hold_button = false;

    /* light handling */
    if (hold_button && !button_hold())
    {
        backlight_on();
    }
    if (remote_hold_button && !remote_button_hold_only())
    {
        remote_backlight_on();
    }

    hold_button = button_hold();
    remote_hold_button = remote_button_hold_only();

    /* normal buttons */
    if (!hold_button)
    {
        data = adc_scan(ADC_BUTTONS);
        
        if (data < 0x80)
            if (data < 0x30)
                if (data < 0x18)
                    btn = BUTTON_SELECT;
                else
                    btn = BUTTON_UP;
            else
                if (data < 0x50)
                    btn = BUTTON_LEFT;
                else
                    btn = BUTTON_DOWN;
        else
            if (data < 0xb0)
                if (data < 0xa0)
                    btn = BUTTON_RIGHT;
                else
                    btn = BUTTON_OFF;
            else
                if (data < 0xd0)
                    btn = BUTTON_MODE;
                else
                    if (data < 0xf0)
                        btn = BUTTON_REC;
    }
    
    /* remote buttons */
    if (!remote_hold_button)
    {
        data = adc_scan(ADC_REMOTE);

        if (data < 0x74)
            if (data < 0x40)
                if (data < 0x20)
                    if(data < 0x10)
                        btn = BUTTON_RC_STOP;
                    else
                        btn = BUTTON_RC_VOL_DOWN;
                else
                    btn = BUTTON_RC_MODE;
            else
                if (data < 0x58)
                    btn = BUTTON_RC_VOL_UP;
                else
                    btn = BUTTON_RC_BITRATE;
        else
            if (data < 0xb0)
                if (data < 0x88)
                    btn = BUTTON_RC_REC;
                else
                    btn = BUTTON_RC_SOURCE;
            else
                if (data < 0xd8)
                    if(data < 0xc0)
                        btn = BUTTON_RC_FF;
                    else
                        btn = BUTTON_RC_MENU;
                else
                    if (data < 0xf0)
                        btn = BUTTON_RC_REW;
    }
    
    /* special buttons */
    data = GPIO1_READ;
    if (!hold_button && ((data & 0x20) == 0))
        btn |= BUTTON_ON;
    if (!remote_hold_button && ((data & 0x40) == 0))
        btn |= BUTTON_RC_ON;
    
#elif CONFIG_KEYPAD == IRIVER_H300_PAD

    static bool hold_button = false;
    static bool remote_hold_button = false;

    /* light handling */
    if (hold_button && !button_hold())
    {
        backlight_on();
    }
    if (remote_hold_button && !remote_button_hold_only())
    {
        remote_backlight_on();
    }

    hold_button = button_hold();
    remote_hold_button = remote_button_hold_only();

    /* normal buttons */
    if (!hold_button)
    {
        data = adc_scan(ADC_BUTTONS);
        
        if (data < 0x54)
            if (data < 0x30)
                if (data < 0x10)
                    btn = BUTTON_SELECT;
                else
                    btn = BUTTON_UP;
            else
                btn = BUTTON_LEFT;
        else
            if (data < 0x98)
                if (data < 0x76)
                    btn = BUTTON_DOWN;
                else
                    btn = BUTTON_RIGHT;
            else
                if(data < 0xba)
                    btn = BUTTON_OFF;
    }
        
    /* remote buttons */
    if (!remote_hold_button)
    {
        data = adc_scan(ADC_REMOTE);

        if (data < 0x74)
            if (data < 0x40)
                if (data < 0x20)
                    if(data < 0x10)
                        btn = BUTTON_RC_STOP;
                    else
                        btn = BUTTON_RC_VOL_DOWN;
                else
                    btn = BUTTON_RC_MODE;
            else
                if (data < 0x58)
                    btn = BUTTON_RC_VOL_UP;
                else
                    btn = BUTTON_RC_BITRATE;
        else
            if (data < 0xb0)
                if (data < 0x88)
                    btn = BUTTON_RC_REC;
                else
                    btn = BUTTON_RC_SOURCE;
            else
                if (data < 0xd8)
                    if(data < 0xc0)
                        btn = BUTTON_RC_FF;
                    else
                        btn = BUTTON_RC_MENU;
                else
                    if (data < 0xf0)
                        btn = BUTTON_RC_REW;
    }

    /* special buttons */
    if (!hold_button)
    {
        data = GPIO_READ;
        if ((data & 0x0200) == 0)
            btn |= BUTTON_MODE;
        if ((data & 0x8000) == 0)
            btn |= BUTTON_REC;
    }
    
    data = GPIO1_READ;
    if (!hold_button && ((data & 0x20) == 0))
        btn |= BUTTON_ON;
    if (!remote_hold_button && ((data & 0x40) == 0))
        btn |= BUTTON_RC_ON;
    
#elif CONFIG_KEYPAD == IRIVER_IFP7XX_PAD

    static bool hold_button = false;

    /* light handling */
    if (hold_button && !button_hold())
    {
        backlight_on();
    }
    hold_button = button_hold();

    /* normal buttons */
    if (!button_hold())
    {
        data = adc_read(ADC_BUTTONS);
        
        if (data < 0x151)
            if (data < 0xc7)
                if (data < 0x41)
                    btn = BUTTON_LEFT;
                else
                    btn = BUTTON_RIGHT;
            else
                btn = BUTTON_SELECT;
        else
            if (data < 0x268)
                if (data < 0x1d7)
                    btn = BUTTON_UP;
                else
                    btn = BUTTON_DOWN;
            else
                if (data < 0x2f9)
                    btn = BUTTON_EQ;
                else
                    if (data < 0x35c)
                        btn = BUTTON_MODE;
    }
    
    if (!button_hold() && (adc_read(ADC_BUTTON_PLAY) < 0x64))
        btn |= BUTTON_PLAY;

#elif CONFIG_KEYPAD == RECORDER_PAD

#ifdef HAVE_FMADC
    if ( adc_read(ADC_BUTTON_ON) < 512 )
        btn |= BUTTON_ON;
    if ( adc_read(ADC_BUTTON_OFF) > 512 )
        btn |= BUTTON_OFF;
#else
    /* check port B pins for ON and OFF */
    data = PBDR;
    if ((data & 0x0100) == 0)
        btn |= BUTTON_ON;
    if ((data & 0x0010) == 0)
        btn |= BUTTON_OFF;
#endif

    /* check F1..F3 and UP */
    data = adc_read(ADC_BUTTON_ROW1);

    if (data >= LEVEL4)
        btn |= BUTTON_F3;
    else if (data >= LEVEL3)
        btn |= BUTTON_UP;
    else if (data >= LEVEL2)
        btn |= BUTTON_F2;
    else if (data >= LEVEL1)
        btn |= BUTTON_F1;

    /* Some units have mushy keypads, so pressing UP also activates
       the Left/Right buttons. Let's combat that by skipping the AN5
       checks when UP is pressed. */
    if(!(btn & BUTTON_UP))
    {
        /* check DOWN, PLAY, LEFT, RIGHT */
        data = adc_read(ADC_BUTTON_ROW2);

        if (data >= LEVEL4)
            btn |= BUTTON_DOWN;
        else if (data >= LEVEL3)
            btn |= ROW2_BUTTON3;
        else if (data >= LEVEL2)
            btn |= BUTTON_LEFT;
        else if (data >= LEVEL1)
            btn |= ROW2_BUTTON1;
    }

#elif CONFIG_KEYPAD == PLAYER_PAD

    /* buttons are active low */
    if (adc_read(0) < 0x180)
        btn |= BUTTON_LEFT;
    if (adc_read(1) < 0x180)
        btn |= BUTTON_MENU;
    if(adc_read(2) < 0x180)
        btn |= BUTTON_RIGHT;
    if(adc_read(3) < 0x180)
        btn |= BUTTON_PLAY;

    /* check port A pins for ON and STOP */
    data = PADR;
    if ( !(data & 0x0020) )
        btn |= BUTTON_ON;
    if ( !(data & 0x0800) )
        btn |= BUTTON_STOP;

#elif CONFIG_KEYPAD == ONDIO_PAD

    if(adc_read(ADC_BUTTON_OPTION) > 0x200) /* active high */
        btn |= BUTTON_MENU;
    if(adc_read(ADC_BUTTON_ONOFF) < 0x120) /* active low */
        btn |= BUTTON_OFF;

    /* Check the 4 direction keys */
    data = adc_read(ADC_BUTTON_ROW1);

    if (data >= LEVEL4)
        btn |= BUTTON_LEFT;
    else if (data >= LEVEL3)
        btn |= BUTTON_RIGHT;
    else if (data >= LEVEL2)
        btn |= BUTTON_UP;
    else if (data >= LEVEL1)
        btn |= BUTTON_DOWN;

#elif CONFIG_KEYPAD == GMINI100_PAD

    if (adc_read(7) < 0xE3)
        btn |= BUTTON_LEFT;
    else if (adc_read(7) < 0x1c5)
        btn |= BUTTON_DOWN;
    else if (adc_read(7) < 0x2a2)
        btn |= BUTTON_RIGHT;
    else if (adc_read(7) < 0x38a)
        btn |= BUTTON_UP;

    if (adc_read(6) < 0x233)
        btn |= BUTTON_OFF;
    else if (adc_read(6) < 0x288)
        btn |= BUTTON_PLAY;
    else if (adc_read(6) < 0x355)
        btn |= BUTTON_MENU;

    data = P7;
    if (data & 0x01)
        btn |= BUTTON_ON;

#elif (CONFIG_KEYPAD == IPOD_3G_PAD) || (CONFIG_KEYPAD == IPOD_4G_PAD)
    (void)data;
    /* The int_btn variable is set in the button interrupt handler */
    btn = int_btn;
#endif /* CONFIG_KEYPAD */


#ifdef HAVE_LCD_BITMAP
    if (btn && flipped)
        btn = button_flip(btn); /* swap upside down */
#endif

    /* Filter the button status. It is only accepted if we get the same
       status twice in a row. */
    if (btn != last_read)
        retval = lastbtn;
    else
        retval = btn;
    last_read = btn;

    return retval;
}

#if (CONFIG_KEYPAD == IPOD_4G_PAD)
bool button_hold(void)
{
    return (GPIOA_INPUT_VAL & 0x20)?false:true;
}
#endif

#if (CONFIG_KEYPAD == IRIVER_H100_PAD) || (CONFIG_KEYPAD == IRIVER_H300_PAD)
bool button_hold(void)
{
    return (GPIO1_READ & 0x00000002)?true:false;
}

static bool remote_button_hold_only(void)
{
    return (GPIO1_READ & 0x00100000)?true:false;
}

bool remote_button_hold(void)
{
    return ((GPIO_READ & 0x40000000) == 0)?remote_button_hold_only():false;
}
#endif

#if CONFIG_KEYPAD == IRIVER_IFP7XX_PAD
bool button_hold(void)
{
    return (GPIO5_READ & 4) ? false : true;
}
#endif

#if (CONFIG_KEYPAD == IAUDIO_X5_PAD)
bool button_hold(void)
{
    return (GPIO_READ & 0x08000000)?true:false;
}

bool remote_button_hold(void)
{
    return false; /* TODO X5 */
}
#endif

int button_status(void)
{
    return lastbtn;
}

void button_clear_queue(void)
{
    queue_clear(&button_queue);
}