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9e2c85e076
This is part of the preparation to add support for iPod Nano 3G and Nano 4G. There are some optimisations left, like merging similar blocks of registers that share the same layout, but the base address have changed between SoC generations. Change-Id: I4f06727b4061977141b65d39ae19591bd5b29680
94 lines
2.7 KiB
C
94 lines
2.7 KiB
C
/***************************************************************************
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* __________ __ ___.
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* Open \______ \ ____ ____ | | _\_ |__ _______ ___
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* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
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* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
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* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
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* \/ \/ \/ \/ \/
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* $Id$
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*
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* Copyright (C) 2009 by Bertrik Sikken
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
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* KIND, either express or implied.
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*
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****************************************************************************/
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#include "config.h"
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#include "inttypes.h"
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#include "s5l87xx.h"
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#include "adc.h"
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#include "adc-target.h"
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#include "kernel.h"
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/* Driver for the built-in ADC of the s5l8700
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The ADC is put into standby mode after each conversion.
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*/
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#define ADC_PRESCALER 100 /* 1MHz ADC clock, assuming 100 MHz PCLK */
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#define ADC_DEFAULT (1<<14) | /* prescale enable */ \
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((ADC_PRESCALER-1)<<6) | /* prescaler */ \
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(0<<3) | /* sel_mux */ \
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(0<<2) | /* stdbm */ \
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(0<<1) | /* read_start */ \
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(0<<0) /* enable start */ \
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static struct mutex adc_mtx;
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static struct semaphore adc_wakeup;
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void INT_ADC(void)
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{
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semaphore_release(&adc_wakeup);
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}
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unsigned short adc_read(int channel)
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{
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unsigned short data;
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mutex_lock(&adc_mtx);
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/* set channel and start conversion */
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ADCCON = ADC_DEFAULT |
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(channel << 3) |
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(1 << 0); /* enable start */
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/* wait for conversion */
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semaphore_wait(&adc_wakeup, TIMEOUT_BLOCK);
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/* get the converted data */
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data = ADCDAT0 & 0x3FF;
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/* put ADC back into standby */
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ADCCON |= (1 << 2);
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mutex_unlock(&adc_mtx);
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return data;
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}
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void adc_init(void)
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{
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mutex_init(&adc_mtx);
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semaphore_init(&adc_wakeup, 1, 0);
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/* enable clock to ADC */
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PWRCON &= ~(1 << 10);
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/* configure ADC and put in standby */
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ADCCON = ADC_DEFAULT | (1 << 2);
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/* configure conversion delay (use default) */
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ADCDLY = 0xFF;
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/* enable interrupt */
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INTMSK |= (1 << 31);
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}
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