rockbox/firmware/backlight.c

/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Copyright (C) 2002 by Linus Nielsen Feltzing
 *
 * 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.
 *
 ****************************************************************************/
#include "config.h"
#include <stdlib.h>
#include "cpu.h"
#include "kernel.h"
#include "thread.h"
#include "i2c.h"
#include "debug.h"
#include "rtc.h"
#include "usb.h"
#include "power.h"
#include "system.h"

#ifdef HAVE_REMOTE_LCD
#include "lcd-remote.h"
#endif

#ifdef CONFIG_BACKLIGHT

const char backlight_timeout_value[19] =
{
    -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 45, 60, 90
};

#define BACKLIGHT_ON 1
#define BACKLIGHT_OFF 2
#define REMOTE_BACKLIGHT_ON 3
#define REMOTE_BACKLIGHT_OFF 4

static void backlight_thread(void);
static long backlight_stack[DEFAULT_STACK_SIZE/sizeof(long)];
static const char backlight_thread_name[] = "backlight";
static struct event_queue backlight_queue;

static bool charger_was_inserted = 0;
static bool backlight_on_when_charging = 0;

static int backlight_timer;
static unsigned int backlight_timeout = 5;
#ifdef HAVE_REMOTE_LCD
static int remote_backlight_timer;
static unsigned int remote_backlight_timeout = 5;
#endif

#if CONFIG_BACKLIGHT == BL_IRIVER
#define BL_PWM_COUNT    100
/* Cycle interval in ms */
#define BL_PWM_INTERVAL      5000
#define BL_PWM_INTERVAL_IDLE 500000
#define BL_DIM_SPEED    4
#define __backlight_on __backlight_fade_in
#define __backlight_off __backlight_fade_out

#define DIM_STATE_START  0
#define DIM_STATE_MAIN   1
#define DIM_STATE_REMOTE 2

static bool bl_timer_active = false;
static int bl_dim_current = BL_PWM_COUNT;
static int bl_dim_target  = BL_PWM_COUNT;
static int bl_pwm_counter = 0;
static volatile int bl_cycle_counter = 0;

/* Unfortunately we can't dim H1xx remote lcd :/ */
#ifdef HAVE_REMOTE_LCD_DIMMABLE
#define lcd_remote_backlight_on __backlight_fade_remote_in
#define lcd_remote_backlight_off __backlight_fade_remote_out
static int bl_dim_remote_current = BL_PWM_COUNT;
static int bl_dim_remote_target = BL_PWM_COUNT;
static int bl_pwm_remote_counter = 0;
static bool bl_dim_next_interval;
#endif

static int bl_dim_state = 0;

void backlight_start_timer(void)
{
    unsigned int count;
    
    if (bl_timer_active)
        return ;
        
    count = 1;
    bl_timer_active = true;

    /* We are using timer 1 */
    TRR1 = count; /* The reference count */
    TCN1 = 0; /* reset the timer */
    TMR1 = 0x011d; /* prescaler=2, restart, CLK/16, enabled */

    TER1 = 0xff; /* Clear all events */
    
    /* ICR2 (Timer2) */
    ICR0 = (ICR0 & 0xffff00ff) | 0x00009000; /* Interrupt on level 4.0 */
    IMR &= ~(1<<10);
}

void TIMER1(void) __attribute__ ((interrupt_handler));
void TIMER1(void)
{
    int timer_period;
#ifdef HAVE_REMOTE_LCD_DIMMABLE
    int new_timer_period;
#endif

    timer_period = FREQ/20000 * BL_PWM_INTERVAL / 100 / 32;
    switch (bl_dim_state) {
    /* New cycle */
    case DIM_STATE_START:
        bl_pwm_counter = 0;
        bl_cycle_counter++;
        
        if (bl_dim_current > 0 && bl_dim_current < BL_PWM_COUNT) {
            GPIO1_OUT &= ~0x00020000;
            bl_pwm_counter = bl_dim_current;
            timer_period = timer_period * bl_pwm_counter / BL_PWM_COUNT;
            bl_dim_state = DIM_STATE_MAIN;
        } else {
            if (bl_dim_current)
                GPIO1_OUT &= ~0x00020000;
            else
                GPIO1_OUT |= 0x00020000;
        }
        
#ifdef HAVE_REMOTE_LCD_DIMMABLE
        bl_dim_next_interval = 0;
        bl_pwm_remote_counter = 0;
        if (bl_dim_remote_current > 0 && 
            bl_dim_remote_current < BL_PWM_COUNT) {
            GPIO_OUT &= ~0x00000800;
            bl_pwm_remote_counter = bl_dim_remote_current;
            if (bl_dim_state == DIM_STATE_START) {
                timer_period = timer_period * bl_pwm_remote_counter 
                               / BL_PWM_COUNT;
                bl_dim_state = DIM_STATE_REMOTE;
                break ;
            }
            
            new_timer_period = timer_period * bl_pwm_remote_counter
                                / BL_PWM_COUNT;
            if (new_timer_period < timer_period) {
                bl_dim_next_interval = timer_period - new_timer_period;
                timer_period = new_timer_period;
                bl_dim_state = DIM_STATE_REMOTE;
            } else {
                bl_dim_next_interval = new_timer_period - timer_period;
            }
        } else {
            if (bl_dim_remote_current)
                GPIO_OUT &= ~0x00000800;
            else
                GPIO_OUT |= 0x00000800;
        }
#endif        
        break ;
        
    /* Dim main screen */
    case DIM_STATE_MAIN:
        GPIO1_OUT |= 0x00020000;
#ifdef HAVE_REMOTE_LCD_DIMMABLE
        if (bl_dim_next_interval) {
            timer_period = bl_dim_next_interval;
            bl_dim_next_interval = 0;
            bl_dim_state = DIM_STATE_REMOTE;
            break ;
        }
#endif
        bl_dim_state = DIM_STATE_START;
        timer_period = timer_period * (BL_PWM_COUNT - bl_pwm_counter) / BL_PWM_COUNT;
        break ;

#ifdef HAVE_REMOTE_LCD_DIMMABLE
    /* Dim remote lcd */
    case DIM_STATE_REMOTE:
        GPIO_OUT |= 0x00000800;
        if (bl_dim_next_interval) {
            timer_period = bl_dim_next_interval;
            bl_dim_next_interval = 0;
            bl_dim_state = DIM_STATE_MAIN;
            break ;
        }
    
        bl_dim_state = DIM_STATE_START;
        timer_period = timer_period * (BL_PWM_COUNT - bl_pwm_remote_counter) / BL_PWM_COUNT;
        break ;
#endif
    }
    
    if (bl_cycle_counter >= BL_DIM_SPEED) {
        bool idle = true;
        if (bl_dim_target > bl_dim_current) {
            bl_dim_current++;
            idle = false;
        }
        else if (bl_dim_target < bl_dim_current) {
            bl_dim_current--;
            idle = false;
        }
#ifdef HAVE_REMOTE_LCD_DIMMABLE
        if (bl_dim_remote_target > bl_dim_remote_current) {
            bl_dim_remote_current++;
            idle = false;
        }
        else if (bl_dim_remote_target < bl_dim_remote_current) {
            bl_dim_remote_current--;
            idle = false;
        }
#endif
        bl_cycle_counter = 0;
        
        /* Save CPU & battery when idle, stop timer */
        if (idle) {
            bl_timer_active = false;
            TMR1 = 0;
        }
    }
    
    TRR1 = timer_period;
    TCN1 = 0;
    TER1 = 0xff; /* Clear all events */
}

static void __backlight_dim(int value)
{
    bl_dim_target = value;
    backlight_start_timer();
}

static void __backlight_fade_in(void)
{
    __backlight_dim(BL_PWM_COUNT);
}

static void __backlight_fade_out(void)
{
    __backlight_dim(0);
}

#ifdef HAVE_REMOTE_LCD_DIMMABLE
static void __backlight_dim_remote(int value)
{
    bl_dim_remote_target = value;
}

static void __backlight_fade_remote_in(void)
{
    __backlight_dim_remote(BL_PWM_COUNT);
}

static void __backlight_fade_remote_out(void)
{
    __backlight_dim_remote(0);
}
#endif

#else
static void __backlight_off(void)
{
#if CONFIG_BACKLIGHT == BL_IRIVER
    GPIO1_OUT  |= 0x00020000;
#elif CONFIG_BACKLIGHT == BL_RTC
    /* Disable square wave */
    rtc_write(0x0a, rtc_read(0x0a) & ~0x40);
#elif CONFIG_BACKLIGHT == BL_PA14_LO /* Player */
    and_b(~0x40, &PAIORH); /* let it float (up) */
#elif CONFIG_BACKLIGHT == BL_PA14_HI /* Ondio */
    and_b(~0x40, &PADRH); /* drive it low */
#elif CONFIG_BACKLIGHT == BL_GMINI
    P1 &= ~0x10;
#endif
}

static void __backlight_on(void)
{
#if CONFIG_BACKLIGHT == BL_IRIVER
    GPIO1_OUT  &= ~0x00020000;
#elif CONFIG_BACKLIGHT == BL_RTC
    /* Enable square wave */
    rtc_write(0x0a, rtc_read(0x0a) | 0x40);
#elif CONFIG_BACKLIGHT == BL_PA14_LO /* Player */
    and_b(~0x40, &PADRH); /* drive and set low */
    or_b(0x40, &PAIORH);
#elif CONFIG_BACKLIGHT == BL_PA14_HI /* Ondio */
    or_b(0x40, &PADRH); /* drive it high */
#elif CONFIG_BACKLIGHT == BL_GMINI
    P1 |= 0x10;
#endif
}
#endif

void backlight_thread(void)
{
    struct event ev;
    
    while(1)
    {
        queue_wait(&backlight_queue, &ev);
        switch(ev.id)
        {
#ifdef HAVE_REMOTE_LCD
            case REMOTE_BACKLIGHT_ON:
                remote_backlight_timer =
                    HZ*backlight_timeout_value[remote_backlight_timeout];

                /* Backlight == OFF in the setting? */
                if(remote_backlight_timer < 0)
                {
                    remote_backlight_timer = 0; /* Disable the timeout */
                    lcd_remote_backlight_off();
                }
                else 
                {
                    lcd_remote_backlight_on();
                }
                break;

            case REMOTE_BACKLIGHT_OFF:
                lcd_remote_backlight_off();
                break;
                
#endif
            case BACKLIGHT_ON:
                if( backlight_on_when_charging && charger_inserted() )
                {
                    /* Forcing to zero keeps the lights on */
                    backlight_timer = 0;
                }
                else
                {
                    backlight_timer = HZ*backlight_timeout_value[backlight_timeout];
                }

                if(backlight_timer < 0) /* Backlight == OFF in the setting? */
                {
                    backlight_timer = 0; /* Disable the timeout */
                    __backlight_off();
                }
                else 
                {
                    __backlight_on();
                }
                break;
                
            case BACKLIGHT_OFF:
                __backlight_off();
                break;
                
            case SYS_USB_CONNECTED:
                /* Tell the USB thread that we are safe */
                DEBUGF("backlight_thread got SYS_USB_CONNECTED\n");
                usb_acknowledge(SYS_USB_CONNECTED_ACK);
                break;

            case SYS_USB_DISCONNECTED:
                usb_acknowledge(SYS_USB_DISCONNECTED_ACK);
                break;
        }
    }
}

void backlight_on(void)
{
    queue_post(&backlight_queue, BACKLIGHT_ON, NULL);
}

void backlight_off(void)
{
    queue_post(&backlight_queue, BACKLIGHT_OFF, NULL);
}

#ifdef HAVE_REMOTE_LCD
void remote_backlight_on(void)
{
    queue_post(&backlight_queue, REMOTE_BACKLIGHT_ON, NULL);
}

void remote_backlight_off(void)
{
    queue_post(&backlight_queue, REMOTE_BACKLIGHT_OFF, NULL);
}

void remote_backlight_set_timeout(int index)
{
    if((unsigned)index >= sizeof(backlight_timeout_value))
        /* if given a weird value, use 0 */
        index=0;
    remote_backlight_timeout = index; /* index in the backlight_timeout_value table */
    remote_backlight_on();
}
#endif

int backlight_get_timeout(void)
{
    return backlight_timeout;
}

void backlight_set_timeout(int index)
{
    if((unsigned)index >= sizeof(backlight_timeout_value))
        /* if given a weird value, use 0 */
        index=0;
    backlight_timeout = index; /* index in the backlight_timeout_value table */
    backlight_on();
}

#ifdef HAVE_CHARGE_CTRL
bool backlight_get_on_when_charging(void)
{
    return backlight_on_when_charging;
}
#endif

void backlight_set_on_when_charging(bool yesno)
{
    backlight_on_when_charging = yesno;
    backlight_on();
}

void backlight_tick(void)
{
    bool charger_is_inserted = charger_inserted();
    if( backlight_on_when_charging &&
        (charger_was_inserted != charger_is_inserted) )
    {
        backlight_on();
    }
    charger_was_inserted = charger_is_inserted;
    
    if(backlight_timer)
    {
        backlight_timer--;
        if(backlight_timer == 0)
        {
            backlight_off();
        }
    }
#ifdef HAVE_REMOTE_LCD
    if(remote_backlight_timer)
    {
        remote_backlight_timer--;
        if(remote_backlight_timer == 0)
        {
            remote_backlight_off();
        }
    }
#endif
}

void backlight_init(void)
{
    queue_init(&backlight_queue);
    create_thread(backlight_thread, backlight_stack,
                  sizeof(backlight_stack), backlight_thread_name);
                  
#if CONFIG_BACKLIGHT == BL_IRIVER
    GPIO1_ENABLE  |= 0x00020000;
    GPIO1_FUNCTION |= 0x00020000;
#elif CONFIG_BACKLIGHT == BL_PA14_LO || CONFIG_BACKLIGHT == BL_PA14_HI
    PACR1 &= ~0x3000;    /* Set PA14 (backlight control) to GPIO */
    or_b(0x40, &PAIORH); /* ..and output */
#elif CONFIG_BACKLIGHT == BL_GMINI
    P1CON |= 0x10; /* P1.4 C-MOS output mode */
#endif    
    backlight_on();
#ifdef HAVE_REMOTE_LCD
    remote_backlight_on();
#endif
}

#else /* no backlight, empty dummy functions */

void backlight_init(void) {}
void backlight_on(void) {}
void backlight_off(void) {}
void backlight_tick(void) {}
int  backlight_get_timeout(void) {return 0;}
void backlight_set_timeout(int index) {(void)index;}
void backlight_set_on_when_charging(bool yesno) {(void)yesno;}
#ifdef HAVE_REMOTE_LCD
void remote_backlight_on(void) {}
void remote_backlight_off(void) {}
void remote_backlight_set_timeout(int index) {(void)index;}
#endif
#endif /* #ifdef CONFIG_BACKLIGHT */