1*b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0 21da177e4SLinus Torvalds /* 31da177e4SLinus Torvalds * linux/arch/sh/kernel/adc.c -- SH3 on-chip ADC support 41da177e4SLinus Torvalds * 51da177e4SLinus Torvalds * Copyright (C) 2004 Andriy Skulysh <askulysh@image.kiev.ua> 61da177e4SLinus Torvalds */ 71da177e4SLinus Torvalds 81da177e4SLinus Torvalds #include <linux/module.h> 91da177e4SLinus Torvalds #include <asm/adc.h> 101da177e4SLinus Torvalds #include <asm/io.h> 111da177e4SLinus Torvalds 121da177e4SLinus Torvalds adc_single(unsigned int channel)131da177e4SLinus Torvaldsint adc_single(unsigned int channel) 141da177e4SLinus Torvalds { 151da177e4SLinus Torvalds int off; 161da177e4SLinus Torvalds unsigned char csr; 171da177e4SLinus Torvalds 181da177e4SLinus Torvalds if (channel >= 8) return -1; 191da177e4SLinus Torvalds 201da177e4SLinus Torvalds off = (channel & 0x03) << 2; 211da177e4SLinus Torvalds 229d56dd3bSPaul Mundt csr = __raw_readb(ADCSR); 231da177e4SLinus Torvalds csr = channel | ADCSR_ADST | ADCSR_CKS; 249d56dd3bSPaul Mundt __raw_writeb(csr, ADCSR); 251da177e4SLinus Torvalds 261da177e4SLinus Torvalds do { 279d56dd3bSPaul Mundt csr = __raw_readb(ADCSR); 281da177e4SLinus Torvalds } while ((csr & ADCSR_ADF) == 0); 291da177e4SLinus Torvalds 301da177e4SLinus Torvalds csr &= ~(ADCSR_ADF | ADCSR_ADST); 319d56dd3bSPaul Mundt __raw_writeb(csr, ADCSR); 321da177e4SLinus Torvalds 339d56dd3bSPaul Mundt return (((__raw_readb(ADDRAH + off) << 8) | 349d56dd3bSPaul Mundt __raw_readb(ADDRAL + off)) >> 6); 351da177e4SLinus Torvalds } 361da177e4SLinus Torvalds 371da177e4SLinus Torvalds EXPORT_SYMBOL(adc_single); 38