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1// SPDX-License-Identifier: GPL-2.02/*3 * AD7606 Parallel Interface ADC driver4 *5 * Copyright 2011 Analog Devices Inc.6 */7 8#include <linux/mod_devicetable.h>9#include <linux/module.h>10#include <linux/gpio/consumer.h>11#include <linux/platform_device.h>12#include <linux/types.h>13#include <linux/err.h>14#include <linux/io.h>15 16#include <linux/iio/iio.h>17#include "ad7606.h"18 19static int ad7606_par16_read_block(struct device *dev,20 int count, void *buf)21{22 struct iio_dev *indio_dev = dev_get_drvdata(dev);23 struct ad7606_state *st = iio_priv(indio_dev);24 25 26 /*27 * On the parallel interface, the frstdata signal is set to high while28 * and after reading the sample of the first channel and low for all29 * other channels. This can be used to check that the incoming data is30 * correctly aligned. During normal operation the data should never31 * become unaligned, but some glitch or electrostatic discharge might32 * cause an extra read or clock cycle. Monitoring the frstdata signal33 * allows to recover from such failure situations.34 */35 int num = count;36 u16 *_buf = buf;37 38 if (st->gpio_frstdata) {39 insw((unsigned long)st->base_address, _buf, 1);40 if (!gpiod_get_value(st->gpio_frstdata)) {41 ad7606_reset(st);42 return -EIO;43 }44 _buf++;45 num--;46 }47 insw((unsigned long)st->base_address, _buf, num);48 return 0;49}50 51static const struct ad7606_bus_ops ad7606_par16_bops = {52 .read_block = ad7606_par16_read_block,53};54 55static int ad7606_par8_read_block(struct device *dev,56 int count, void *buf)57{58 struct iio_dev *indio_dev = dev_get_drvdata(dev);59 struct ad7606_state *st = iio_priv(indio_dev);60 /*61 * On the parallel interface, the frstdata signal is set to high while62 * and after reading the sample of the first channel and low for all63 * other channels. This can be used to check that the incoming data is64 * correctly aligned. During normal operation the data should never65 * become unaligned, but some glitch or electrostatic discharge might66 * cause an extra read or clock cycle. Monitoring the frstdata signal67 * allows to recover from such failure situations.68 */69 int num = count;70 u16 *_buf = buf;71 72 if (st->gpio_frstdata) {73 insb((unsigned long)st->base_address, _buf, 2);74 if (!gpiod_get_value(st->gpio_frstdata)) {75 ad7606_reset(st);76 return -EIO;77 }78 _buf++;79 num--;80 }81 insb((unsigned long)st->base_address, _buf, num * 2);82 83 return 0;84}85 86static const struct ad7606_bus_ops ad7606_par8_bops = {87 .read_block = ad7606_par8_read_block,88};89 90static int ad7606_par_probe(struct platform_device *pdev)91{92 const struct platform_device_id *id = platform_get_device_id(pdev);93 struct resource *res;94 void __iomem *addr;95 resource_size_t remap_size;96 int irq;97 98 irq = platform_get_irq(pdev, 0);99 if (irq < 0)100 return irq;101 102 addr = devm_platform_get_and_ioremap_resource(pdev, 0, &res);103 if (IS_ERR(addr))104 return PTR_ERR(addr);105 106 remap_size = resource_size(res);107 108 return ad7606_probe(&pdev->dev, irq, addr,109 id->name, id->driver_data,110 remap_size > 1 ? &ad7606_par16_bops :111 &ad7606_par8_bops);112}113 114static const struct platform_device_id ad7606_driver_ids[] = {115 { .name = "ad7605-4", .driver_data = ID_AD7605_4, },116 { .name = "ad7606-4", .driver_data = ID_AD7606_4, },117 { .name = "ad7606-6", .driver_data = ID_AD7606_6, },118 { .name = "ad7606-8", .driver_data = ID_AD7606_8, },119 { }120};121MODULE_DEVICE_TABLE(platform, ad7606_driver_ids);122 123static const struct of_device_id ad7606_of_match[] = {124 { .compatible = "adi,ad7605-4" },125 { .compatible = "adi,ad7606-4" },126 { .compatible = "adi,ad7606-6" },127 { .compatible = "adi,ad7606-8" },128 { }129};130MODULE_DEVICE_TABLE(of, ad7606_of_match);131 132static struct platform_driver ad7606_driver = {133 .probe = ad7606_par_probe,134 .id_table = ad7606_driver_ids,135 .driver = {136 .name = "ad7606",137 .pm = AD7606_PM_OPS,138 .of_match_table = ad7606_of_match,139 },140};141module_platform_driver(ad7606_driver);142 143MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");144MODULE_DESCRIPTION("Analog Devices AD7606 ADC");145MODULE_LICENSE("GPL v2");146MODULE_IMPORT_NS(IIO_AD7606);147