firmware/target/arm/ipod/backlight-nano_video.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2002 by Linus Nielsen Feltzing
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21 #include "config.h"
  22 #include <stdlib.h>
  23 #include "cpu.h"
  24 #include "kernel.h"
  25 #include "thread.h"
  26 #include "i2c.h"
  27 #include "debug.h"
  28 #include "rtc.h"
  29 #include "usb.h"
  30 #include "power.h"
  31 #include "system.h"
  32 #include "button.h"
  33 #include "timer.h"
  34 #include "backlight.h"
  35 #include "backlight-target.h"
  36
  37 static int brightness = 1;   /* 1 to 32 */
  38 static int current_dim = 16; /* default after enabling the backlight dimmer */
  39 static bool enabled = false;
  40
  41 void _backlight_set_brightness(int val)
  42 {
  43     int oldlevel;
  44
  45     if (current_dim < val)
  46     {
  47         do
  48         {
  49             oldlevel = disable_irq_save();
  50             GPIO_CLEAR_BITWISE(GPIOD_OUTPUT_VAL, 0x80);
  51             udelay(10);
  52             GPIO_SET_BITWISE(GPIOD_OUTPUT_VAL, 0x80);
  53             restore_irq(oldlevel);
  54             udelay(10);
  55         }
  56         while (++current_dim < val);
  57     }
  58     else if (current_dim > val)
  59     {
  60         do
  61         {
  62             oldlevel = disable_irq_save();
  63             GPIO_CLEAR_BITWISE(GPIOD_OUTPUT_VAL, 0x80);
  64             udelay(200);
  65             GPIO_SET_BITWISE(GPIOD_OUTPUT_VAL, 0x80);
  66             restore_irq(oldlevel);
  67             udelay(10);
  68         }
  69         while (--current_dim > val);
  70     }
  71     brightness = val;
  72 }
  73
  74 void _backlight_hw_enable(bool on)
  75 {
  76 #ifdef HAVE_LCD_SLEEP
  77     if (on)
  78         /* If the fade-out is interrupted, enabled will be true, but
  79            lcd_awake() needs to be called anyways because the LCD
  80            may be sleeping.
  81          */
  82         lcd_awake();
  83 #endif
  84
  85     if (on == enabled)
  86         return;
  87
  88     if (on)
  89     {
  90         GPIO_SET_BITWISE(GPIOB_OUTPUT_VAL, 0x08);
  91         GPIO_SET_BITWISE(GPIOD_OUTPUT_VAL, 0x80);
  92         sleep(HZ/100);
  93         current_dim = 16;
  94         _backlight_set_brightness(brightness);
  95     }
  96     else
  97     {
  98         GPIO_CLEAR_BITWISE(GPIOD_OUTPUT_VAL, 0x80);
  99         GPIO_CLEAR_BITWISE(GPIOB_OUTPUT_VAL, 0x08);
 100         sleep(HZ/20);
 101     }
 102     enabled = on;
 103 }
 104
 105 /* Switch the backlight on. Works only if the backlight circuit is enabled.
 106  * Called in ISR context for fading, so it must be fast. */
 107 void _backlight_led_on(void)
 108 {
 109     GPIO_SET_BITWISE(GPIOL_OUTPUT_VAL, 0x80);
 110 }
 111
 112 /* Switch the backlight off. Keeps the backlight circuit enabled.
 113  * Called in ISR context for fading, so it must be fast. */
 114 void _backlight_led_off(void)
 115 {
 116     GPIO_CLEAR_BITWISE(GPIOL_OUTPUT_VAL, 0x80);
 117 }
 118
 119 bool _backlight_init(void)
 120 {
 121     GPIO_SET_BITWISE(GPIOB_ENABLE, 0x08);
 122     GPIO_SET_BITWISE(GPIOB_OUTPUT_EN, 0x08);
 123     GPIO_SET_BITWISE(GPIOD_ENABLE, 0x80);
 124     GPIO_SET_BITWISE(GPIOD_OUTPUT_EN, 0x80);
 125     _backlight_hw_enable(true);
 126     GPIO_SET_BITWISE(GPIOL_ENABLE, 0x80);
 127     GPIO_SET_BITWISE(GPIOL_OUTPUT_EN, 0x80);
 128     GPIO_SET_BITWISE(GPIOL_OUTPUT_VAL, 0x80);
 129
 130     return true;
 131 }