/* | |
* linux/arch/sh/kernel/adc.c -- SH3 on-chip ADC support | |
* | |
* Copyright (C) 2004 Andriy Skulysh <askulysh@image.kiev.ua> | |
*/ | |
#include <linux/module.h> | |
#include <asm/adc.h> | |
#include <asm/io.h> | |
int adc_single(unsigned int channel) | |
{ | |
int off; | |
unsigned char csr; | |
if (channel >= 8) return -1; | |
off = (channel & 0x03) << 2; | |
csr = ctrl_inb(ADCSR); | |
csr = channel | ADCSR_ADST | ADCSR_CKS; | |
ctrl_outb(csr, ADCSR); | |
do { | |
csr = ctrl_inb(ADCSR); | |
} while ((csr & ADCSR_ADF) == 0); | |
csr &= ~(ADCSR_ADF | ADCSR_ADST); | |
ctrl_outb(csr, ADCSR); | |
return (((ctrl_inb(ADDRAH + off) << 8) | | |
ctrl_inb(ADDRAL + off)) >> 6); | |
} | |
EXPORT_SYMBOL(adc_single); |