rockbox/firmware/target/arm/adc-pp5020.c
Daniel Stenberg 2acc0ac542 Updated our source code header to explicitly mention that we are GPL v2 or
later. We still need to hunt down snippets used that are not. 1324 modified
files...
http://www.rockbox.org/mail/archive/rockbox-dev-archive-2008-06/0060.shtml


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@17847 a1c6a512-1295-4272-9138-f99709370657
2008-06-28 18:10:04 +00:00

145 lines
3.6 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2006 by Barry Wardell
*
* 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 "cpu.h"
#include "system.h"
#include "kernel.h"
#include "thread.h"
#include "adc.h"
static unsigned short adcdata[NUM_ADC_CHANNELS];
/* Scan ADC so that adcdata[channel] gets updated. */
unsigned short adc_scan(int channel)
{
unsigned int adc_data_1;
unsigned int adc_data_2;
/* Start conversion */
ADC_ADDR |= 0x80000000;
/* Wait for conversion to complete */
while((ADC_STATUS & (0x40<<8*channel))==0);
/* Stop conversion */
ADC_ADDR &=~ 0x80000000;
/* ADC_DATA_1 and ADC_DATA_2 are both four bytes, one byte per channel.
For each channel, ADC_DATA_1 stores the 8-bit msb, ADC_DATA_2 stores the
2-bit lsb (in bits 0 and 1). Each channel is 10 bits total. */
adc_data_1 = ((ADC_DATA_1 >> (8*channel)) & 0xff);
adc_data_2 = ((ADC_DATA_2 >> (8*channel+6)) & 0x3);
adcdata[channel] = (adc_data_1<<2 | adc_data_2);
/* ADC values read low if PLL is enabled */
if(PLL_CONTROL & 0x80000000){
adcdata[channel] += 0x14;
if(adcdata[channel] > 0x400)
adcdata[channel] = 0x400;
}
return adcdata[channel];
}
/* Read 10-bit channel data */
unsigned short adc_read(int channel)
{
return adcdata[channel];
}
static int adc_counter;
static void adc_tick(void)
{
if(++adc_counter == HZ)
{
adc_counter = 0;
adc_scan(0);
adc_scan(1);
adc_scan(2);
adc_scan(3);
}
}
/* Figured out from how the OF does things */
void adc_init(void)
{
ADC_INIT |= 1;
ADC_INIT |= 0x40000000;
udelay(100);
/* Reset ADC */
DEV_RS2 |= 0x20;
udelay(100);
DEV_RS2 &=~ 0x20;
udelay(100);
/* Enable ADC */
DEV_EN2 |= 0x20;
udelay(100);
ADC_CLOCK_SRC |= 0x3;
udelay(100);
ADC_ADDR |= 0x40;
ADC_ADDR |= 0x20000000;
udelay(100);
ADC_INIT;
ADC_INIT = 0;
udelay(100);
ADC_STATUS = 0;
/* Enable channel 0 (battery) */
DEV_INIT1 &=~0x3;
ADC_ADDR |= 0x1000000;
ADC_STATUS |= 0x20;
/* Enable channel 1 (unknown) */
DEV_INIT1 &=~30;
ADC_ADDR |= 0x2000000;
ADC_STATUS |= 0x2000;
#if defined (IRIVER_H10) || defined(IRIVER_H10_5GB) || defined(MROBE_100)
/* Enable channel 2 (H10:remote) */
DEV_INIT1 &=~0x300;
DEV_INIT1 |= 0x100;
ADC_ADDR |= 0x4000000;
ADC_STATUS |= 0x200000;
/* Enable channel 3 (H10:scroll pad) */
DEV_INIT1 &=~0x3000;
DEV_INIT1 |= 0x1000;
ADC_ADDR |= 0x8000000;
ADC_STATUS |= 0x20000000;
#endif
/* Force a scan of all channels to get initial values */
adc_scan(0);
adc_scan(1);
adc_scan(2);
adc_scan(3);
tick_add_task(adc_tick);
}