rockbox/firmware/target/arm/as3525/sansa-clipzip/button-clipzip.c
Bertrik Sikken eb7cf73dcb Sansa clip zip: use a state machine for scanning buttons to avoid busy-waits
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30871 a1c6a512-1295-4272-9138-f99709370657
2011-10-30 20:15:08 +00:00

117 lines
2.9 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2008 François Dinel
* Copyright © 2008-2009 Rafaël Carré
*
* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "config.h"
#include "button-target.h"
#include "as3525v2.h"
#include "kernel.h"
#include "system-target.h"
static int keyscan(void)
{
static int buttons = 0;
static int row = 1;
switch (row) {
case 1:
/* read row 1 */
buttons &= ~(BUTTON_RIGHT | BUTTON_SELECT | BUTTON_UP);
if (GPIOC_PIN(3)) {
buttons |= BUTTON_RIGHT;
}
if (GPIOC_PIN(4)) {
buttons |= BUTTON_SELECT;
}
if (GPIOC_PIN(5)) {
buttons |= BUTTON_UP;
}
/* prepare row 2 */
GPIOC_PIN(1) = 0;
GPIOC_PIN(2) = (1 << 2);
row = 2;
break;
case 2:
/* read row 2 */
buttons &= ~(BUTTON_HOME | BUTTON_DOWN | BUTTON_LEFT);
if (GPIOC_PIN(3)) {
buttons |= BUTTON_HOME;
}
if (GPIOC_PIN(4)) {
buttons |= BUTTON_DOWN;
}
if (GPIOC_PIN(5)) {
buttons |= BUTTON_LEFT;
}
/* prepare row 1 */
GPIOC_PIN(1) = (1 << 1);
GPIOC_PIN(2) = 0;
row = 1;
break;
default:
row = 1;
break;
}
return buttons;
}
void button_init_device(void)
{
/* GPIO A6, A7 and D6 are direct button inputs */
GPIOA_DIR &= ~(1 << 6);
GPIOA_DIR &= ~(1 << 7);
GPIOD_DIR &= ~(1 << 6);
/* GPIO C1, C2, C3, C4, C5 are used in a column/row key scan matrix */
GPIOC_DIR |= ((1 << 1) | (1 << 2));
GPIOC_DIR &= ~((1 << 3) | (1 << 4) | (1 << 5));
}
int button_read_device(void)
{
int buttons = 0;
/* power */
if (GPIOD_PIN(6)) {
buttons |= BUTTON_POWER;
}
/* volume */
if (GPIOA_PIN(6)) {
buttons |= BUTTON_VOL_DOWN;
}
if (GPIOA_PIN(7)) {
buttons |= BUTTON_VOL_UP;
}
/* keyscan buttons */
buttons |= keyscan();
return buttons;
}