counter: 104-quad-8: Add Generic Counter interface support

This patch adds support for the Generic Counter interface to the
104-QUAD-8 driver. The existing 104-QUAD-8 device interface should not
be affected by this patch; all changes are intended as supplemental
additions as perceived by the user.

Generic Counter Counts are created for the eight quadrature channel
counts, as well as their respective quadrature A and B Signals (which
are associated via respective Synapse structures) and respective index
Signals.

The new Generic Counter interface sysfs attributes are intended to
expose the same functionality and data available via the existing
104-QUAD-8 IIO device interface; the Generic Counter interface serves
to provide the respective functionality and data in a standard way
expected of counter devices.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

3 files changed, 0 insertions, 641 deletions

diff --git a/drivers/iio/counter/104-quad-8.c b/drivers/iio/counter/104-quad-8.c
deleted file mode 100644
index 72b6352e09f0..000000000000
--- a/drivers/iio/counter/104-quad-8.c
+++ /dev/null
@@ -1,623 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * IIO driver for the ACCES 104-QUAD-8
- * Copyright (C) 2016 William Breathitt Gray
- *
- * This driver supports the ACCES 104-QUAD-8 and ACCES 104-QUAD-4.
- */
-#include <linux/bitops.h>
-#include <linux/device.h>
-#include <linux/errno.h>
-#include <linux/iio/iio.h>
-#include <linux/iio/types.h>
-#include <linux/io.h>
-#include <linux/ioport.h>
-#include <linux/isa.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/moduleparam.h>
-#include <linux/types.h>
-
-#define QUAD8_EXTENT 32
-
-static unsigned int base[max_num_isa_dev(QUAD8_EXTENT)];
-static unsigned int num_quad8;
-module_param_array(base, uint, &num_quad8, 0);
-MODULE_PARM_DESC(base, "ACCES 104-QUAD-8 base addresses");
-
-#define QUAD8_NUM_COUNTERS 8
-
-/**
- * struct quad8_iio - IIO device private data structure
- * @preset:		array of preset values
- * @count_mode:		array of count mode configurations
- * @quadrature_mode:	array of quadrature mode configurations
- * @quadrature_scale:	array of quadrature mode scale configurations
- * @ab_enable:		array of A and B inputs enable configurations
- * @preset_enable:	array of set_to_preset_on_index attribute configurations
- * @synchronous_mode:	array of index function synchronous mode configurations
- * @index_polarity:	array of index function polarity configurations
- * @base:		base port address of the IIO device
- */
-struct quad8_iio {
-	unsigned int preset[QUAD8_NUM_COUNTERS];
-	unsigned int count_mode[QUAD8_NUM_COUNTERS];
-	unsigned int quadrature_mode[QUAD8_NUM_COUNTERS];
-	unsigned int quadrature_scale[QUAD8_NUM_COUNTERS];
-	unsigned int ab_enable[QUAD8_NUM_COUNTERS];
-	unsigned int preset_enable[QUAD8_NUM_COUNTERS];
-	unsigned int synchronous_mode[QUAD8_NUM_COUNTERS];
-	unsigned int index_polarity[QUAD8_NUM_COUNTERS];
-	unsigned int base;
-};
-
-#define QUAD8_REG_CHAN_OP 0x11
-#define QUAD8_REG_INDEX_INPUT_LEVELS 0x16
-/* Borrow Toggle flip-flop */
-#define QUAD8_FLAG_BT BIT(0)
-/* Carry Toggle flip-flop */
-#define QUAD8_FLAG_CT BIT(1)
-/* Error flag */
-#define QUAD8_FLAG_E BIT(4)
-/* Up/Down flag */
-#define QUAD8_FLAG_UD BIT(5)
-/* Reset and Load Signal Decoders */
-#define QUAD8_CTR_RLD 0x00
-/* Counter Mode Register */
-#define QUAD8_CTR_CMR 0x20
-/* Input / Output Control Register */
-#define QUAD8_CTR_IOR 0x40
-/* Index Control Register */
-#define QUAD8_CTR_IDR 0x60
-/* Reset Byte Pointer (three byte data pointer) */
-#define QUAD8_RLD_RESET_BP 0x01
-/* Reset Counter */
-#define QUAD8_RLD_RESET_CNTR 0x02
-/* Reset Borrow Toggle, Carry Toggle, Compare Toggle, and Sign flags */
-#define QUAD8_RLD_RESET_FLAGS 0x04
-/* Reset Error flag */
-#define QUAD8_RLD_RESET_E 0x06
-/* Preset Register to Counter */
-#define QUAD8_RLD_PRESET_CNTR 0x08
-/* Transfer Counter to Output Latch */
-#define QUAD8_RLD_CNTR_OUT 0x10
-#define QUAD8_CHAN_OP_ENABLE_COUNTERS 0x00
-#define QUAD8_CHAN_OP_RESET_COUNTERS 0x01
-
-static int quad8_read_raw(struct iio_dev *indio_dev,
-	struct iio_chan_spec const *chan, int *val, int *val2, long mask)
-{
-	struct quad8_iio *const priv = iio_priv(indio_dev);
-	const int base_offset = priv->base + 2 * chan->channel;
-	unsigned int flags;
-	unsigned int borrow;
-	unsigned int carry;
-	int i;
-
-	switch (mask) {
-	case IIO_CHAN_INFO_RAW:
-		if (chan->type == IIO_INDEX) {
-			*val = !!(inb(priv->base + QUAD8_REG_INDEX_INPUT_LEVELS)
-				& BIT(chan->channel));
-			return IIO_VAL_INT;
-		}
-
-		flags = inb(base_offset + 1);
-		borrow = flags & QUAD8_FLAG_BT;
-		carry = !!(flags & QUAD8_FLAG_CT);
-
-		/* Borrow XOR Carry effectively doubles count range */
-		*val = (borrow ^ carry) << 24;
-
-		/* Reset Byte Pointer; transfer Counter to Output Latch */
-		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP | QUAD8_RLD_CNTR_OUT,
-		     base_offset + 1);
-
-		for (i = 0; i < 3; i++)
-			*val |= (unsigned int)inb(base_offset) << (8 * i);
-
-		return IIO_VAL_INT;
-	case IIO_CHAN_INFO_ENABLE:
-		*val = priv->ab_enable[chan->channel];
-		return IIO_VAL_INT;
-	case IIO_CHAN_INFO_SCALE:
-		*val = 1;
-		*val2 = priv->quadrature_scale[chan->channel];
-		return IIO_VAL_FRACTIONAL_LOG2;
-	}
-
-	return -EINVAL;
-}
-
-static int quad8_write_raw(struct iio_dev *indio_dev,
-	struct iio_chan_spec const *chan, int val, int val2, long mask)
-{
-	struct quad8_iio *const priv = iio_priv(indio_dev);
-	const int base_offset = priv->base + 2 * chan->channel;
-	int i;
-	unsigned int ior_cfg;
-
-	switch (mask) {
-	case IIO_CHAN_INFO_RAW:
-		if (chan->type == IIO_INDEX)
-			return -EINVAL;
-
-		/* Only 24-bit values are supported */
-		if ((unsigned int)val > 0xFFFFFF)
-			return -EINVAL;
-
-		/* Reset Byte Pointer */
-		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
-
-		/* Counter can only be set via Preset Register */
-		for (i = 0; i < 3; i++)
-			outb(val >> (8 * i), base_offset);
-
-		/* Transfer Preset Register to Counter */
-		outb(QUAD8_CTR_RLD | QUAD8_RLD_PRESET_CNTR, base_offset + 1);
-
-		/* Reset Byte Pointer */
-		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
-
-		/* Set Preset Register back to original value */
-		val = priv->preset[chan->channel];
-		for (i = 0; i < 3; i++)
-			outb(val >> (8 * i), base_offset);
-
-		/* Reset Borrow, Carry, Compare, and Sign flags */
-		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_FLAGS, base_offset + 1);
-		/* Reset Error flag */
-		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_E, base_offset + 1);
-
-		return 0;
-	case IIO_CHAN_INFO_ENABLE:
-		/* only boolean values accepted */
-		if (val < 0 || val > 1)
-			return -EINVAL;
-
-		priv->ab_enable[chan->channel] = val;
-
-		ior_cfg = val | priv->preset_enable[chan->channel] << 1;
-
-		/* Load I/O control configuration */
-		outb(QUAD8_CTR_IOR | ior_cfg, base_offset + 1);
-
-		return 0;
-	case IIO_CHAN_INFO_SCALE:
-		/* Quadrature scaling only available in quadrature mode */
-		if (!priv->quadrature_mode[chan->channel] && (val2 || val != 1))
-			return -EINVAL;
-
-		/* Only three gain states (1, 0.5, 0.25) */
-		if (val == 1 && !val2)
-			priv->quadrature_scale[chan->channel] = 0;
-		else if (!val)
-			switch (val2) {
-			case 500000:
-				priv->quadrature_scale[chan->channel] = 1;
-				break;
-			case 250000:
-				priv->quadrature_scale[chan->channel] = 2;
-				break;
-			default:
-				return -EINVAL;
-			}
-		else
-			return -EINVAL;
-
-		return 0;
-	}
-
-	return -EINVAL;
-}
-
-static const struct iio_info quad8_info = {
-	.read_raw = quad8_read_raw,
-	.write_raw = quad8_write_raw
-};
-
-static ssize_t quad8_read_preset(struct iio_dev *indio_dev, uintptr_t private,
-	const struct iio_chan_spec *chan, char *buf)
-{
-	const struct quad8_iio *const priv = iio_priv(indio_dev);
-
-	return snprintf(buf, PAGE_SIZE, "%u\n", priv->preset[chan->channel]);
-}
-
-static ssize_t quad8_write_preset(struct iio_dev *indio_dev, uintptr_t private,
-	const struct iio_chan_spec *chan, const char *buf, size_t len)
-{
-	struct quad8_iio *const priv = iio_priv(indio_dev);
-	const int base_offset = priv->base + 2 * chan->channel;
-	unsigned int preset;
-	int ret;
-	int i;
-
-	ret = kstrtouint(buf, 0, &preset);
-	if (ret)
-		return ret;
-
-	/* Only 24-bit values are supported */
-	if (preset > 0xFFFFFF)
-		return -EINVAL;
-
-	priv->preset[chan->channel] = preset;
-
-	/* Reset Byte Pointer */
-	outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
-
-	/* Set Preset Register */
-	for (i = 0; i < 3; i++)
-		outb(preset >> (8 * i), base_offset);
-
-	return len;
-}
-
-static ssize_t quad8_read_set_to_preset_on_index(struct iio_dev *indio_dev,
-	uintptr_t private, const struct iio_chan_spec *chan, char *buf)
-{
-	const struct quad8_iio *const priv = iio_priv(indio_dev);
-
-	return snprintf(buf, PAGE_SIZE, "%u\n",
-		!priv->preset_enable[chan->channel]);
-}
-
-static ssize_t quad8_write_set_to_preset_on_index(struct iio_dev *indio_dev,
-	uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
-	size_t len)
-{
-	struct quad8_iio *const priv = iio_priv(indio_dev);
-	const int base_offset = priv->base + 2 * chan->channel + 1;
-	bool preset_enable;
-	int ret;
-	unsigned int ior_cfg;
-
-	ret = kstrtobool(buf, &preset_enable);
-	if (ret)
-		return ret;
-
-	/* Preset enable is active low in Input/Output Control register */
-	preset_enable = !preset_enable;
-
-	priv->preset_enable[chan->channel] = preset_enable;
-
-	ior_cfg = priv->ab_enable[chan->channel] |
-		(unsigned int)preset_enable << 1;
-
-	/* Load I/O control configuration to Input / Output Control Register */
-	outb(QUAD8_CTR_IOR | ior_cfg, base_offset);
-
-	return len;
-}
-
-static const char *const quad8_noise_error_states[] = {
-	"No excessive noise is present at the count inputs",
-	"Excessive noise is present at the count inputs"
-};
-
-static int quad8_get_noise_error(struct iio_dev *indio_dev,
-	const struct iio_chan_spec *chan)
-{
-	struct quad8_iio *const priv = iio_priv(indio_dev);
-	const int base_offset = priv->base + 2 * chan->channel + 1;
-
-	return !!(inb(base_offset) & QUAD8_FLAG_E);
-}
-
-static const struct iio_enum quad8_noise_error_enum = {
-	.items = quad8_noise_error_states,
-	.num_items = ARRAY_SIZE(quad8_noise_error_states),
-	.get = quad8_get_noise_error
-};
-
-static const char *const quad8_count_direction_states[] = {
-	"down",
-	"up"
-};
-
-static int quad8_get_count_direction(struct iio_dev *indio_dev,
-	const struct iio_chan_spec *chan)
-{
-	struct quad8_iio *const priv = iio_priv(indio_dev);
-	const int base_offset = priv->base + 2 * chan->channel + 1;
-
-	return !!(inb(base_offset) & QUAD8_FLAG_UD);
-}
-
-static const struct iio_enum quad8_count_direction_enum = {
-	.items = quad8_count_direction_states,
-	.num_items = ARRAY_SIZE(quad8_count_direction_states),
-	.get = quad8_get_count_direction
-};
-
-static const char *const quad8_count_modes[] = {
-	"normal",
-	"range limit",
-	"non-recycle",
-	"modulo-n"
-};
-
-static int quad8_set_count_mode(struct iio_dev *indio_dev,
-	const struct iio_chan_spec *chan, unsigned int count_mode)
-{
-	struct quad8_iio *const priv = iio_priv(indio_dev);
-	unsigned int mode_cfg = count_mode << 1;
-	const int base_offset = priv->base + 2 * chan->channel + 1;
-
-	priv->count_mode[chan->channel] = count_mode;
-
-	/* Add quadrature mode configuration */
-	if (priv->quadrature_mode[chan->channel])
-		mode_cfg |= (priv->quadrature_scale[chan->channel] + 1) << 3;
-
-	/* Load mode configuration to Counter Mode Register */
-	outb(QUAD8_CTR_CMR | mode_cfg, base_offset);
-
-	return 0;
-}
-
-static int quad8_get_count_mode(struct iio_dev *indio_dev,
-	const struct iio_chan_spec *chan)
-{
-	const struct quad8_iio *const priv = iio_priv(indio_dev);
-
-	return priv->count_mode[chan->channel];
-}
-
-static const struct iio_enum quad8_count_mode_enum = {
-	.items = quad8_count_modes,
-	.num_items = ARRAY_SIZE(quad8_count_modes),
-	.set = quad8_set_count_mode,
-	.get = quad8_get_count_mode
-};
-
-static const char *const quad8_synchronous_modes[] = {
-	"non-synchronous",
-	"synchronous"
-};
-
-static int quad8_set_synchronous_mode(struct iio_dev *indio_dev,
-	const struct iio_chan_spec *chan, unsigned int synchronous_mode)
-{
-	struct quad8_iio *const priv = iio_priv(indio_dev);
-	const unsigned int idr_cfg = synchronous_mode |
-		priv->index_polarity[chan->channel] << 1;
-	const int base_offset = priv->base + 2 * chan->channel + 1;
-
-	/* Index function must be non-synchronous in non-quadrature mode */
-	if (synchronous_mode && !priv->quadrature_mode[chan->channel])
-		return -EINVAL;
-
-	priv->synchronous_mode[chan->channel] = synchronous_mode;
-
-	/* Load Index Control configuration to Index Control Register */
-	outb(QUAD8_CTR_IDR | idr_cfg, base_offset);
-
-	return 0;
-}
-
-static int quad8_get_synchronous_mode(struct iio_dev *indio_dev,
-	const struct iio_chan_spec *chan)
-{
-	const struct quad8_iio *const priv = iio_priv(indio_dev);
-
-	return priv->synchronous_mode[chan->channel];
-}
-
-static const struct iio_enum quad8_synchronous_mode_enum = {
-	.items = quad8_synchronous_modes,
-	.num_items = ARRAY_SIZE(quad8_synchronous_modes),
-	.set = quad8_set_synchronous_mode,
-	.get = quad8_get_synchronous_mode
-};
-
-static const char *const quad8_quadrature_modes[] = {
-	"non-quadrature",
-	"quadrature"
-};
-
-static int quad8_set_quadrature_mode(struct iio_dev *indio_dev,
-	const struct iio_chan_spec *chan, unsigned int quadrature_mode)
-{
-	struct quad8_iio *const priv = iio_priv(indio_dev);
-	unsigned int mode_cfg = priv->count_mode[chan->channel] << 1;
-	const int base_offset = priv->base + 2 * chan->channel + 1;
-
-	if (quadrature_mode)
-		mode_cfg |= (priv->quadrature_scale[chan->channel] + 1) << 3;
-	else {
-		/* Quadrature scaling only available in quadrature mode */
-		priv->quadrature_scale[chan->channel] = 0;
-
-		/* Synchronous function not supported in non-quadrature mode */
-		if (priv->synchronous_mode[chan->channel])
-			quad8_set_synchronous_mode(indio_dev, chan, 0);
-	}
-
-	priv->quadrature_mode[chan->channel] = quadrature_mode;
-
-	/* Load mode configuration to Counter Mode Register */
-	outb(QUAD8_CTR_CMR | mode_cfg, base_offset);
-
-	return 0;
-}
-
-static int quad8_get_quadrature_mode(struct iio_dev *indio_dev,
-	const struct iio_chan_spec *chan)
-{
-	const struct quad8_iio *const priv = iio_priv(indio_dev);
-
-	return priv->quadrature_mode[chan->channel];
-}
-
-static const struct iio_enum quad8_quadrature_mode_enum = {
-	.items = quad8_quadrature_modes,
-	.num_items = ARRAY_SIZE(quad8_quadrature_modes),
-	.set = quad8_set_quadrature_mode,
-	.get = quad8_get_quadrature_mode
-};
-
-static const char *const quad8_index_polarity_modes[] = {
-	"negative",
-	"positive"
-};
-
-static int quad8_set_index_polarity(struct iio_dev *indio_dev,
-	const struct iio_chan_spec *chan, unsigned int index_polarity)
-{
-	struct quad8_iio *const priv = iio_priv(indio_dev);
-	const unsigned int idr_cfg = priv->synchronous_mode[chan->channel] |
-		index_polarity << 1;
-	const int base_offset = priv->base + 2 * chan->channel + 1;
-
-	priv->index_polarity[chan->channel] = index_polarity;
-
-	/* Load Index Control configuration to Index Control Register */
-	outb(QUAD8_CTR_IDR | idr_cfg, base_offset);
-
-	return 0;
-}
-
-static int quad8_get_index_polarity(struct iio_dev *indio_dev,
-	const struct iio_chan_spec *chan)
-{
-	const struct quad8_iio *const priv = iio_priv(indio_dev);
-
-	return priv->index_polarity[chan->channel];
-}
-
-static const struct iio_enum quad8_index_polarity_enum = {
-	.items = quad8_index_polarity_modes,
-	.num_items = ARRAY_SIZE(quad8_index_polarity_modes),
-	.set = quad8_set_index_polarity,
-	.get = quad8_get_index_polarity
-};
-
-static const struct iio_chan_spec_ext_info quad8_count_ext_info[] = {
-	{
-		.name = "preset",
-		.shared = IIO_SEPARATE,
-		.read = quad8_read_preset,
-		.write = quad8_write_preset
-	},
-	{
-		.name = "set_to_preset_on_index",
-		.shared = IIO_SEPARATE,
-		.read = quad8_read_set_to_preset_on_index,
-		.write = quad8_write_set_to_preset_on_index
-	},
-	IIO_ENUM("noise_error", IIO_SEPARATE, &quad8_noise_error_enum),
-	IIO_ENUM_AVAILABLE("noise_error", &quad8_noise_error_enum),
-	IIO_ENUM("count_direction", IIO_SEPARATE, &quad8_count_direction_enum),
-	IIO_ENUM_AVAILABLE("count_direction", &quad8_count_direction_enum),
-	IIO_ENUM("count_mode", IIO_SEPARATE, &quad8_count_mode_enum),
-	IIO_ENUM_AVAILABLE("count_mode", &quad8_count_mode_enum),
-	IIO_ENUM("quadrature_mode", IIO_SEPARATE, &quad8_quadrature_mode_enum),
-	IIO_ENUM_AVAILABLE("quadrature_mode", &quad8_quadrature_mode_enum),
-	{}
-};
-
-static const struct iio_chan_spec_ext_info quad8_index_ext_info[] = {
-	IIO_ENUM("synchronous_mode", IIO_SEPARATE,
-		&quad8_synchronous_mode_enum),
-	IIO_ENUM_AVAILABLE("synchronous_mode", &quad8_synchronous_mode_enum),
-	IIO_ENUM("index_polarity", IIO_SEPARATE, &quad8_index_polarity_enum),
-	IIO_ENUM_AVAILABLE("index_polarity", &quad8_index_polarity_enum),
-	{}
-};
-
-#define QUAD8_COUNT_CHAN(_chan) {					\
-	.type = IIO_COUNT,						\
-	.channel = (_chan),						\
-	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
-		BIT(IIO_CHAN_INFO_ENABLE) | BIT(IIO_CHAN_INFO_SCALE),	\
-	.ext_info = quad8_count_ext_info,				\
-	.indexed = 1							\
-}
-
-#define QUAD8_INDEX_CHAN(_chan) {			\
-	.type = IIO_INDEX,				\
-	.channel = (_chan),				\
-	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
-	.ext_info = quad8_index_ext_info,		\
-	.indexed = 1					\
-}
-
-static const struct iio_chan_spec quad8_channels[] = {
-	QUAD8_COUNT_CHAN(0), QUAD8_INDEX_CHAN(0),
-	QUAD8_COUNT_CHAN(1), QUAD8_INDEX_CHAN(1),
-	QUAD8_COUNT_CHAN(2), QUAD8_INDEX_CHAN(2),
-	QUAD8_COUNT_CHAN(3), QUAD8_INDEX_CHAN(3),
-	QUAD8_COUNT_CHAN(4), QUAD8_INDEX_CHAN(4),
-	QUAD8_COUNT_CHAN(5), QUAD8_INDEX_CHAN(5),
-	QUAD8_COUNT_CHAN(6), QUAD8_INDEX_CHAN(6),
-	QUAD8_COUNT_CHAN(7), QUAD8_INDEX_CHAN(7)
-};
-
-static int quad8_probe(struct device *dev, unsigned int id)
-{
-	struct iio_dev *indio_dev;
-	struct quad8_iio *priv;
-	int i, j;
-	unsigned int base_offset;
-
-	indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
-	if (!indio_dev)
-		return -ENOMEM;
-
-	if (!devm_request_region(dev, base[id], QUAD8_EXTENT,
-		dev_name(dev))) {
-		dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
-			base[id], base[id] + QUAD8_EXTENT);
-		return -EBUSY;
-	}
-
-	indio_dev->info = &quad8_info;
-	indio_dev->modes = INDIO_DIRECT_MODE;
-	indio_dev->num_channels = ARRAY_SIZE(quad8_channels);
-	indio_dev->channels = quad8_channels;
-	indio_dev->name = dev_name(dev);
-	indio_dev->dev.parent = dev;
-
-	priv = iio_priv(indio_dev);
-	priv->base = base[id];
-
-	/* Reset all counters and disable interrupt function */
-	outb(QUAD8_CHAN_OP_RESET_COUNTERS, base[id] + QUAD8_REG_CHAN_OP);
-	/* Set initial configuration for all counters */
-	for (i = 0; i < QUAD8_NUM_COUNTERS; i++) {
-		base_offset = base[id] + 2 * i;
-		/* Reset Byte Pointer */
-		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
-		/* Reset Preset Register */
-		for (j = 0; j < 3; j++)
-			outb(0x00, base_offset);
-		/* Reset Borrow, Carry, Compare, and Sign flags */
-		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_FLAGS, base_offset + 1);
-		/* Reset Error flag */
-		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_E, base_offset + 1);
-		/* Binary encoding; Normal count; non-quadrature mode */
-		outb(QUAD8_CTR_CMR, base_offset + 1);
-		/* Disable A and B inputs; preset on index; FLG1 as Carry */
-		outb(QUAD8_CTR_IOR, base_offset + 1);
-		/* Disable index function; negative index polarity */
-		outb(QUAD8_CTR_IDR, base_offset + 1);
-	}
-	/* Enable all counters */
-	outb(QUAD8_CHAN_OP_ENABLE_COUNTERS, base[id] + QUAD8_REG_CHAN_OP);
-
-	return devm_iio_device_register(dev, indio_dev);
-}
-
-static struct isa_driver quad8_driver = {
-	.probe = quad8_probe,
-	.driver = {
-		.name = "104-quad-8"
-	}
-};
-
-module_isa_driver(quad8_driver, num_quad8);
-
-MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
-MODULE_DESCRIPTION("ACCES 104-QUAD-8 IIO driver");
-MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/counter/Kconfig b/drivers/iio/counter/Kconfig
index bf1e559ad7cd..eeb358122cbe 100644
--- a/drivers/iio/counter/Kconfig
+++ b/drivers/iio/counter/Kconfig
@@ -5,23 +5,6 @@
 
 menu "Counters"
 
-config 104_QUAD_8
-	tristate "ACCES 104-QUAD-8 driver"
-	depends on PC104 && X86
-	select ISA_BUS_API
-	help
-	  Say yes here to build support for the ACCES 104-QUAD-8 quadrature
-	  encoder counter/interface device family (104-QUAD-8, 104-QUAD-4).
-
-	  Performing a write to a counter's IIO_CHAN_INFO_RAW sets the counter and
-	  also clears the counter's respective error flag. Although the counters
-	  have a 25-bit range, only the lower 24 bits may be set, either directly
-	  or via a counter's preset attribute. Interrupts are not supported by
-	  this driver.
-
-	  The base port addresses for the devices may be configured via the base
-	  array module parameter.
-
 config STM32_LPTIMER_CNT
 	tristate "STM32 LP Timer encoder counter driver"
 	depends on MFD_STM32_LPTIMER || COMPILE_TEST
diff --git a/drivers/iio/counter/Makefile b/drivers/iio/counter/Makefile
index 1b9a896eb488..93933ba49280 100644
--- a/drivers/iio/counter/Makefile
+++ b/drivers/iio/counter/Makefile
@@ -4,5 +4,4 @@
 
 # When adding new entries keep the list in alphabetical order
 
-obj-$(CONFIG_104_QUAD_8)	+= 104-quad-8.o
 obj-$(CONFIG_STM32_LPTIMER_CNT)	+= stm32-lptimer-cnt.o