rockbox/firmware/target/arm/sandisk/sansa-e200/adc-e200.c
2007-07-12 04:19:21 +00:00

56 lines
1.6 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2006 by Barry Wardell
*
* All files in this archive are subject to the GNU General Public License.
* See the file COPYING in the source tree root for full license agreement.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "adc.h"
#include "kernel.h"
#include "i2c-pp.h"
#include "as3514.h"
static struct mutex adc_mutex NOCACHEBSS_ATTR;
/* Read 10-bit channel data */
unsigned short adc_read(int channel)
{
unsigned short data = 0;
if ((unsigned)channel < NUM_ADC_CHANNELS)
{
spinlock_lock(&adc_mutex);
/* Select channel */
if (pp_i2c_send( AS3514_I2C_ADDR, ADC_0, (channel << 4)) >= 0)
{
unsigned char buf[2];
/* Read data */
if (i2c_readbytes( AS3514_I2C_ADDR, ADC_0, 2, buf) >= 0)
{
data = (((buf[0] & 0x3) << 8) | buf[1]);
}
}
spinlock_unlock(&adc_mutex);
}
return data;
}
void adc_init(void)
{
spinlock_init(&adc_mutex);
}