firmware/target/arm/as3525/sansa-fuze/button-fuze.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2008 by Thomas Martitz
  11  * Copyright (C) 2008 by Dominik Wenger
  12  *
  13  * This program is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU General Public License
  15  * as published by the Free Software Foundation; either version 2
  16  * of the License, or (at your option) any later version.
  17  *
  18  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  19  * KIND, either express or implied.
  20  *
  21  ****************************************************************************/
  22
  23
  24 /* Basic button driver for the Fuze
  25  *
  26  * TODO: - Get the wheel working with interrupts
  27  *       - find that Home button
  28  */
  29
  30 #include "system.h"
  31 #include "button.h"
  32 #include "button-target.h"
  33 #include "backlight.h"
  34
  35 #define WHEEL_REPEAT_INTERVAL   30
  36 #define WHEELCLICKS_PER_ROTATION    48 /* wheelclicks per full rotation */
  37
  38 #ifndef BOOTLOADER
  39 /* Buttons */
  40 static bool hold_button     = false;
  41 static bool hold_button_old = false;
  42 #else
  43 #define hold_button false
  44 #endif /* !BOOTLOADER */
  45 static int      int_btn         = BUTTON_NONE;
  46 static short    dbop_din        = BUTTON_NONE;
  47
  48 void button_init_device(void)
  49 {
  50     GPIOA_DIR |= (1<<1);
  51     GPIOA_PIN(1) = (1<<1);
  52 }
  53
  54 /* clickwheel */
  55 #if !defined(BOOTLOADER) && defined(HAVE_SCROLLWHEEL)
  56 static void get_wheel(void)
  57 {
  58     static unsigned int  old_wheel_value    = 0;
  59     static unsigned int  wheel_value        = 0;
  60     static unsigned int  wheel_repeat       = BUTTON_NONE;
  61     /* getting BUTTON_REPEAT works like this: We increment repeat by if the
  62      * wheel was turned, and decrement it by 1 each tick,
  63      * that means: if you change the wheel fast enough, repeat will be >1 and
  64      * we send BUTTON_REPEAT
  65      */
  66     static int repeat;
  67     /* we omit 3 of 4 posts to the button_queue, that works better, so count */
  68     static int counter = 0;
  69     /* Read wheel
  70      * Bits 13 and 14 of DBOP_DIN change as follows:
  71      * Clockwise rotation   00 -> 01 -> 11 -> 10 -> 00
  72      * Counter-clockwise    00 -> 10 -> 11 -> 01 -> 00
  73      */
  74     static const unsigned char wheel_tbl[2][4] =
  75     {
  76         { 2, 0, 3, 1 }, /* Clockwise rotation */
  77         { 1, 3, 0, 2 }, /* Counter-clockwise  */
  78     };
  79     wheel_value = dbop_din & (1<<13|1<<14);
  80     wheel_value >>= 13;
  81     /* did the wheel value change? */
  82     if (!hold_button)
  83     {
  84         unsigned int btn = BUTTON_NONE;
  85         if (old_wheel_value == wheel_tbl[0][wheel_value])
  86             btn = BUTTON_SCROLL_FWD;
  87         else if (old_wheel_value == wheel_tbl[1][wheel_value])
  88             btn = BUTTON_SCROLL_BACK;
  89
  90         if (btn != BUTTON_NONE)
  91         {
  92             if (btn != wheel_repeat)
  93             {
  94                 /* direction reversals nullify repeats */
  95                 wheel_repeat      = btn;
  96                 repeat            = 0;
  97             }
  98             if (btn != BUTTON_NONE)
  99             {
 100                 /* generate repeats if quick enough */
 101                 if (repeat > 0)
 102                 {
 103                     btn |= BUTTON_REPEAT;
 104                 }
 105                 repeat += 2;
 106                 /* the wheel is more reliable if we don't send ever change,
 107                  * every 4th is basically one "physical click" is 1 item in
 108                  * the rockbox menus */
 109                 if (queue_empty(&button_queue) && ++counter >= 4)
 110                 {
 111                     buttonlight_on();
 112                     backlight_on();
 113                     /* 1<<24 is rather arbitary, seems to work well */
 114                     queue_post(&button_queue, btn, 1<<24);
 115                     /* message posted - reset count */
 116                     counter = 0;
 117                 }
 118             }
 119         }
 120     }
 121     if (repeat > 0)
 122         repeat--;
 123     else
 124         repeat = 0;
 125     old_wheel_value = wheel_value;
 126 }
 127 #endif /* !defined(BOOTLOADER) && defined(SCROLLWHEEL) */
 128
 129 #if !defined(BOOTLOADER)
 130 /* get hold button state */
 131 static void get_hold(void)
 132 {
 133     hold_button = dbop_din & (1<<12);
 134 }
 135 #endif
 136
 137 bool button_hold(void)
 138 {
 139     return hold_button;
 140 }
 141
 142 static void get_power(void)
 143 {
 144     if (dbop_din & (1<<8))
 145         int_btn |= BUTTON_POWER;
 146 }
 147
 148 static void get_button_from_dbob(void)
 149 {
 150     int_btn &= ~(BUTTON_HOLD|
 151                 BUTTON_POWER);
 152
 153     /* Wait for fifo to empty */
 154     while ((DBOP_STAT & (1<<10)) == 0);
 155
 156     DBOP_CTRL |= (1<<19);
 157     DBOP_CTRL &= ~(1<<16); /* disable output */
 158
 159     DBOP_TIMPOL_01 = 0xe167e167;
 160     DBOP_TIMPOL_23 = 0xe167006e;
 161     int loop = 0;
 162     do
 163     {
 164         asm volatile ("nop\n");
 165         loop++;
 166     } while(loop < 64);
 167
 168     DBOP_CTRL |= (1<<15); /* start read */
 169     int temp;
 170     do
 171     {
 172         temp = DBOP_STAT;
 173     } while ((temp & (1<<16)) == 0); /* wait for valid data */
 174
 175     dbop_din = DBOP_DIN; /* now read */
 176
 177     DBOP_TIMPOL_01 = 0x6e167;
 178     DBOP_TIMPOL_23 = 0xa167e06f;
 179
 180     DBOP_CTRL |= (1<<16);
 181     DBOP_CTRL &= ~(1<<19);
 182
 183 #if !defined(BOOTLOADER)
 184     get_hold();
 185 #if defined(HAVE_SCROLLWHEEL)
 186     get_wheel();
 187 #endif
 188 #endif
 189     get_power();
 190 }
 191
 192 static void get_button_from_gpio(void)
 193 {
 194     /* reset buttons we're going to read */
 195     int_btn &= ~(BUTTON_LEFT|
 196                 BUTTON_RIGHT|
 197                 BUTTON_UP|
 198                 BUTTON_DOWN|
 199                 BUTTON_SELECT);
 200     if(hold_button)
 201         return;
 202     /* set afsel, so that we can read our buttons */
 203     GPIOC_AFSEL &= ~(1<<2|1<<3|1<<4|1<<5|1<<6);
 204     /* set dir so we can read our buttons (but reset the C pins first) */
 205     GPIOB_DIR &= ~(1<<4);
 206     GPIOC_DIR |= (1<<2|1<<3|1<<4|1<<5|1<<6);
 207     GPIOC_PIN(2) |= (1<<2);
 208     GPIOC_PIN(3) |= (1<<3);
 209     GPIOC_PIN(4) |= (1<<4);
 210     GPIOC_PIN(5) |= (1<<5);
 211     GPIOC_PIN(6) |= (1<<6);
 212
 213     GPIOC_DIR &= ~(1<<2|1<<3|1<<4|1<<5|1<<6);
 214
 215     /* small delay needed to read buttons correctly */
 216     int delay = 50;
 217     while(delay >0) delay--;
 218
 219     /* direct GPIO connections */
 220     if (!GPIOC_PIN(3))
 221         int_btn |= BUTTON_LEFT;
 222     if (!GPIOC_PIN(2))
 223         int_btn |= BUTTON_UP;
 224     if (!GPIOC_PIN(6))
 225         int_btn |= BUTTON_DOWN;
 226     if (!GPIOC_PIN(5))
 227         int_btn |= BUTTON_RIGHT;
 228     if (!GPIOC_PIN(4))
 229         int_btn |= BUTTON_SELECT;
 230     /* return to settings needed for lcd */
 231     GPIOC_DIR |= (1<<2|1<<3|1<<4|1<<5|1<<6);
 232     GPIOC_AFSEL |= (1<<2|1<<3|1<<4|1<<5|1<<6);
 233 }
 234
 235 static inline void get_buttons_from_hw(void)
 236 {
 237     get_button_from_dbob();
 238     get_button_from_gpio();
 239 }
 240 /*
 241  * Get button pressed from hardware
 242  */
 243 int button_read_device(void)
 244 {
 245     get_buttons_from_hw();
 246 #ifndef BOOTLOADER
 247     /* light handling */
 248     if (hold_button != hold_button_old)
 249     {
 250         hold_button_old = hold_button;
 251         backlight_hold_changed(hold_button);
 252     }
 253 #endif /* BOOTLOADER */
 254
 255     return int_btn; /* set in button_int */
 256 }