diff --git a/MAINTAINERS b/MAINTAINERS
index 7a01aa63fb33..f11bf7885aeb 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -266,12 +266,12 @@ L:	linux-gpio@vger.kernel.org
 S:	Maintained
 F:	drivers/gpio/gpio-104-idio-16.c
 
-ACCES 104-QUAD-8 IIO DRIVER
+ACCES 104-QUAD-8 DRIVER
 M:	William Breathitt Gray <vilhelm.gray@gmail.com>
 L:	linux-iio@vger.kernel.org
 S:	Maintained
 F:	Documentation/ABI/testing/sysfs-bus-iio-counter-104-quad-8
-F:	drivers/iio/counter/104-quad-8.c
+F:	drivers/counter/104-quad-8.c
 
 ACCES PCI-IDIO-16 GPIO DRIVER
 M:	William Breathitt Gray <vilhelm.gray@gmail.com>
diff --git a/drivers/counter/104-quad-8.c b/drivers/counter/104-quad-8.c
new file mode 100644
index 000000000000..7c72fb72d660
--- /dev/null
+++ b/drivers/counter/104-quad-8.c
@@ -0,0 +1,1335 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * IIO driver for the ACCES 104-QUAD-8
+ * Copyright (C) 2016 William Breathitt Gray
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * This driver supports the ACCES 104-QUAD-8 and ACCES 104-QUAD-4.
+ */
+#include <linux/bitops.h>
+#include <linux/counter.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
+ * @counter:		instance of the counter_device
+ * @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 {
+	struct counter_device counter;
+	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;
+};
+
+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 + 0x16) & BIT(chan->channel));
+			return IIO_VAL_INT;
+		}
+
+		flags = inb(base_offset + 1);
+		borrow = flags & BIT(0);
+		carry = !!(flags & BIT(1));
+
+		/* Borrow XOR Carry effectively doubles count range */
+		*val = (borrow ^ carry) << 24;
+
+		/* Reset Byte Pointer; transfer Counter to Output Latch */
+		outb(0x11, 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(0x01, 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(0x08, base_offset + 1);
+
+		/* Reset Byte Pointer */
+		outb(0x01, 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(0x02, base_offset + 1);
+		/* Reset Error flag */
+		outb(0x06, 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(0x40 | 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(0x01, 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(0x40 | 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) & BIT(4));
+}
+
+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) & BIT(5));
+}
+
+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 cnt_mode)
+{
+	struct quad8_iio *const priv = iio_priv(indio_dev);
+	unsigned int mode_cfg = cnt_mode << 1;
+	const int base_offset = priv->base + 2 * chan->channel + 1;
+
+	priv->count_mode[chan->channel] = cnt_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(0x20 | 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(0x60 | 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(0x20 | 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(0x60 | 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_signal_read(struct counter_device *counter,
+	struct counter_signal *signal, struct signal_read_value *val)
+{
+	const struct quad8_iio *const priv = counter->priv;
+	unsigned int state;
+	enum signal_level level;
+
+	/* Only Index signal levels can be read */
+	if (signal->id < 16)
+		return -EINVAL;
+
+	state = inb(priv->base + 0x16) & BIT(signal->id - 16);
+
+	level = (state) ? SIGNAL_LEVEL_HIGH : SIGNAL_LEVEL_LOW;
+
+	set_signal_read_value(val, SIGNAL_LEVEL, &level);
+
+	return 0;
+}
+
+static int quad8_count_read(struct counter_device *counter,
+	struct counter_count *count, struct count_read_value *val)
+{
+	const struct quad8_iio *const priv = counter->priv;
+	const int base_offset = priv->base + 2 * count->id;
+	unsigned int flags;
+	unsigned int borrow;
+	unsigned int carry;
+	unsigned long position;
+	int i;
+
+	flags = inb(base_offset + 1);
+	borrow = flags & BIT(0);
+	carry = !!(flags & BIT(1));
+
+	/* Borrow XOR Carry effectively doubles count range */
+	position = (unsigned long)(borrow ^ carry) << 24;
+
+	/* Reset Byte Pointer; transfer Counter to Output Latch */
+	outb(0x11, base_offset + 1);
+
+	for (i = 0; i < 3; i++)
+		position |= (unsigned long)inb(base_offset) << (8 * i);
+
+	set_count_read_value(val, COUNT_POSITION_UNSIGNED, &position);
+
+	return 0;
+}
+
+static int quad8_count_write(struct counter_device *counter,
+	struct counter_count *count, struct count_write_value *val)
+{
+	const struct quad8_iio *const priv = counter->priv;
+	const int base_offset = priv->base + 2 * count->id;
+	int err;
+	unsigned long position;
+	int i;
+
+	err = get_count_write_value(&position, COUNT_POSITION_UNSIGNED, val);
+	if (err)
+		return err;
+
+	/* Only 24-bit values are supported */
+	if (position > 0xFFFFFF)
+		return -EINVAL;
+
+	/* Reset Byte Pointer */
+	outb(0x01, base_offset + 1);
+
+	/* Counter can only be set via Preset Register */
+	for (i = 0; i < 3; i++)
+		outb(position >> (8 * i), base_offset);
+
+	/* Transfer Preset Register to Counter */
+	outb(0x08, base_offset + 1);
+
+	/* Reset Byte Pointer */
+	outb(0x01, base_offset + 1);
+
+	/* Set Preset Register back to original value */
+	position = priv->preset[count->id];
+	for (i = 0; i < 3; i++)
+		outb(position >> (8 * i), base_offset);
+
+	/* Reset Borrow, Carry, Compare, and Sign flags */
+	outb(0x02, base_offset + 1);
+	/* Reset Error flag */
+	outb(0x06, base_offset + 1);
+
+	return 0;
+}
+
+enum quad8_count_function {
+	QUAD8_COUNT_FUNCTION_PULSE_DIRECTION = 0,
+	QUAD8_COUNT_FUNCTION_QUADRATURE_X1,
+	QUAD8_COUNT_FUNCTION_QUADRATURE_X2,
+	QUAD8_COUNT_FUNCTION_QUADRATURE_X4
+};
+
+static enum count_function quad8_count_functions_list[] = {
+	[QUAD8_COUNT_FUNCTION_PULSE_DIRECTION] = COUNT_FUNCTION_PULSE_DIRECTION,
+	[QUAD8_COUNT_FUNCTION_QUADRATURE_X1] = COUNT_FUNCTION_QUADRATURE_X1_A,
+	[QUAD8_COUNT_FUNCTION_QUADRATURE_X2] = COUNT_FUNCTION_QUADRATURE_X2_A,
+	[QUAD8_COUNT_FUNCTION_QUADRATURE_X4] = COUNT_FUNCTION_QUADRATURE_X4
+};
+
+static int quad8_function_get(struct counter_device *counter,
+	struct counter_count *count, size_t *function)
+{
+	const struct quad8_iio *const priv = counter->priv;
+	const int id = count->id;
+	const unsigned int quadrature_mode = priv->quadrature_mode[id];
+	const unsigned int scale = priv->quadrature_scale[id];
+
+	if (quadrature_mode)
+		switch (scale) {
+		case 0:
+			*function = QUAD8_COUNT_FUNCTION_QUADRATURE_X1;
+			break;
+		case 1:
+			*function = QUAD8_COUNT_FUNCTION_QUADRATURE_X2;
+			break;
+		case 2:
+			*function = QUAD8_COUNT_FUNCTION_QUADRATURE_X4;
+			break;
+		}
+	else
+		*function = QUAD8_COUNT_FUNCTION_PULSE_DIRECTION;
+
+	return 0;
+}
+
+static int quad8_function_set(struct counter_device *counter,
+	struct counter_count *count, size_t function)
+{
+	struct quad8_iio *const priv = counter->priv;
+	const int id = count->id;
+	unsigned int *const quadrature_mode = priv->quadrature_mode + id;
+	unsigned int *const scale = priv->quadrature_scale + id;
+	unsigned int mode_cfg = priv->count_mode[id] << 1;
+	unsigned int *const synchronous_mode = priv->synchronous_mode + id;
+	const unsigned int idr_cfg = priv->index_polarity[id] << 1;
+	const int base_offset = priv->base + 2 * id + 1;
+
+	if (function == QUAD8_COUNT_FUNCTION_PULSE_DIRECTION) {
+		*quadrature_mode = 0;
+
+		/* Quadrature scaling only available in quadrature mode */
+		*scale = 0;
+
+		/* Synchronous function not supported in non-quadrature mode */
+		if (*synchronous_mode) {
+			*synchronous_mode = 0;
+			/* Disable synchronous function mode */
+			outb(0x60 | idr_cfg, base_offset);
+		}
+	} else {
+		*quadrature_mode = 1;
+
+		switch (function) {
+		case QUAD8_COUNT_FUNCTION_QUADRATURE_X1:
+			*scale = 0;
+			mode_cfg |= 0x8;
+			break;
+		case QUAD8_COUNT_FUNCTION_QUADRATURE_X2:
+			*scale = 1;
+			mode_cfg |= 0x10;
+			break;
+		case QUAD8_COUNT_FUNCTION_QUADRATURE_X4:
+			*scale = 2;
+			mode_cfg |= 0x18;
+			break;
+		}
+	}
+
+	/* Load mode configuration to Counter Mode Register */
+	outb(0x20 | mode_cfg, base_offset);
+
+	return 0;
+}
+
+static void quad8_direction_get(struct counter_device *counter,
+	struct counter_count *count, enum count_direction *direction)
+{
+	const struct quad8_iio *const priv = counter->priv;
+	unsigned int ud_flag;
+	const unsigned int flag_addr = priv->base + 2 * count->id + 1;
+
+	/* U/D flag: nonzero = up, zero = down */
+	ud_flag = inb(flag_addr) & BIT(5);
+
+	*direction = (ud_flag) ? COUNT_DIRECTION_FORWARD :
+		COUNT_DIRECTION_BACKWARD;
+}
+
+enum quad8_synapse_action {
+	QUAD8_SYNAPSE_ACTION_NONE = 0,
+	QUAD8_SYNAPSE_ACTION_RISING_EDGE,
+	QUAD8_SYNAPSE_ACTION_FALLING_EDGE,
+	QUAD8_SYNAPSE_ACTION_BOTH_EDGES
+};
+
+static enum synapse_action quad8_index_actions_list[] = {
+	[QUAD8_SYNAPSE_ACTION_NONE] = SYNAPSE_ACTION_NONE,
+	[QUAD8_SYNAPSE_ACTION_RISING_EDGE] = SYNAPSE_ACTION_RISING_EDGE
+};
+
+static enum synapse_action quad8_synapse_actions_list[] = {
+	[QUAD8_SYNAPSE_ACTION_NONE] = SYNAPSE_ACTION_NONE,
+	[QUAD8_SYNAPSE_ACTION_RISING_EDGE] = SYNAPSE_ACTION_RISING_EDGE,
+	[QUAD8_SYNAPSE_ACTION_FALLING_EDGE] = SYNAPSE_ACTION_FALLING_EDGE,
+	[QUAD8_SYNAPSE_ACTION_BOTH_EDGES] = SYNAPSE_ACTION_BOTH_EDGES
+};
+
+static int quad8_action_get(struct counter_device *counter,
+	struct counter_count *count, struct counter_synapse *synapse,
+	size_t *action)
+{
+	struct quad8_iio *const priv = counter->priv;
+	int err;
+	size_t function = 0;
+	const size_t signal_a_id = count->synapses[0].signal->id;
+	enum count_direction direction;
+
+	/* Handle Index signals */
+	if (synapse->signal->id >= 16) {
+		if (priv->preset_enable[count->id])
+			*action = QUAD8_SYNAPSE_ACTION_RISING_EDGE;
+		else
+			*action = QUAD8_SYNAPSE_ACTION_NONE;
+
+		return 0;
+	}
+
+	err = quad8_function_get(counter, count, &function);
+	if (err)
+		return err;
+
+	/* Default action mode */
+	*action = QUAD8_SYNAPSE_ACTION_NONE;
+
+	/* Determine action mode based on current count function mode */
+	switch (function) {
+	case QUAD8_COUNT_FUNCTION_PULSE_DIRECTION:
+		if (synapse->signal->id == signal_a_id)
+			*action = QUAD8_SYNAPSE_ACTION_RISING_EDGE;
+		break;
+	case QUAD8_COUNT_FUNCTION_QUADRATURE_X1:
+		if (synapse->signal->id == signal_a_id) {
+			quad8_direction_get(counter, count, &direction);
+
+			if (direction == COUNT_DIRECTION_FORWARD)
+				*action = QUAD8_SYNAPSE_ACTION_RISING_EDGE;
+			else
+				*action = QUAD8_SYNAPSE_ACTION_FALLING_EDGE;
+		}
+		break;
+	case QUAD8_COUNT_FUNCTION_QUADRATURE_X2:
+		if (synapse->signal->id == signal_a_id)
+			*action = QUAD8_SYNAPSE_ACTION_BOTH_EDGES;
+		break;
+	case QUAD8_COUNT_FUNCTION_QUADRATURE_X4:
+		*action = QUAD8_SYNAPSE_ACTION_BOTH_EDGES;
+		break;
+	}
+
+	return 0;
+}
+
+const struct counter_ops quad8_ops = {
+	.signal_read = quad8_signal_read,
+	.count_read = quad8_count_read,
+	.count_write = quad8_count_write,
+	.function_get = quad8_function_get,
+	.function_set = quad8_function_set,
+	.action_get = quad8_action_get
+};
+
+static int quad8_index_polarity_get(struct counter_device *counter,
+	struct counter_signal *signal, size_t *index_polarity)
+{
+	const struct quad8_iio *const priv = counter->priv;
+	const size_t channel_id = signal->id - 16;
+
+	*index_polarity = priv->index_polarity[channel_id];
+
+	return 0;
+}
+
+static int quad8_index_polarity_set(struct counter_device *counter,
+	struct counter_signal *signal, size_t index_polarity)
+{
+	struct quad8_iio *const priv = counter->priv;
+	const size_t channel_id = signal->id - 16;
+	const unsigned int idr_cfg = priv->synchronous_mode[channel_id] |
+		index_polarity << 1;
+	const int base_offset = priv->base + 2 * channel_id + 1;
+
+	priv->index_polarity[channel_id] = index_polarity;
+
+	/* Load Index Control configuration to Index Control Register */
+	outb(0x60 | idr_cfg, base_offset);
+
+	return 0;
+}
+
+static struct counter_signal_enum_ext quad8_index_pol_enum = {
+	.items = quad8_index_polarity_modes,
+	.num_items = ARRAY_SIZE(quad8_index_polarity_modes),
+	.get = quad8_index_polarity_get,
+	.set = quad8_index_polarity_set
+};
+
+static int quad8_synchronous_mode_get(struct counter_device *counter,
+	struct counter_signal *signal, size_t *synchronous_mode)
+{
+	const struct quad8_iio *const priv = counter->priv;
+	const size_t channel_id = signal->id - 16;
+
+	*synchronous_mode = priv->synchronous_mode[channel_id];
+
+	return 0;
+}
+
+static int quad8_synchronous_mode_set(struct counter_device *counter,
+	struct counter_signal *signal, size_t synchronous_mode)
+{
+	struct quad8_iio *const priv = counter->priv;
+	const size_t channel_id = signal->id - 16;
+	const unsigned int idr_cfg = synchronous_mode |
+		priv->index_polarity[channel_id] << 1;
+	const int base_offset = priv->base + 2 * channel_id + 1;
+
+	/* Index function must be non-synchronous in non-quadrature mode */
+	if (synchronous_mode && !priv->quadrature_mode[channel_id])
+		return -EINVAL;
+
+	priv->synchronous_mode[channel_id] = synchronous_mode;
+
+	/* Load Index Control configuration to Index Control Register */
+	outb(0x60 | idr_cfg, base_offset);
+
+	return 0;
+}
+
+static struct counter_signal_enum_ext quad8_syn_mode_enum = {
+	.items = quad8_synchronous_modes,
+	.num_items = ARRAY_SIZE(quad8_synchronous_modes),
+	.get = quad8_synchronous_mode_get,
+	.set = quad8_synchronous_mode_set
+};
+
+static ssize_t quad8_count_floor_read(struct counter_device *counter,
+	struct counter_count *count, void *private, char *buf)
+{
+	/* Only a floor of 0 is supported */
+	return snprintf(buf, PAGE_SIZE, "0\n");
+}
+
+static int quad8_count_mode_get(struct counter_device *counter,
+	struct counter_count *count, size_t *cnt_mode)
+{
+	const struct quad8_iio *const priv = counter->priv;
+
+	/* Map 104-QUAD-8 count mode to Generic Counter count mode */
+	switch (priv->count_mode[count->id]) {
+	case 0:
+		*cnt_mode = COUNT_MODE_NORMAL;
+		break;
+	case 1:
+		*cnt_mode = COUNT_MODE_RANGE_LIMIT;
+		break;
+	case 2:
+		*cnt_mode = COUNT_MODE_NON_RECYCLE;
+		break;
+	case 3:
+		*cnt_mode = COUNT_MODE_MODULO_N;
+		break;
+	}
+
+	return 0;
+}
+
+static int quad8_count_mode_set(struct counter_device *counter,
+	struct counter_count *count, size_t cnt_mode)
+{
+	struct quad8_iio *const priv = counter->priv;
+	unsigned int mode_cfg;
+	const int base_offset = priv->base + 2 * count->id + 1;
+
+	/* Map Generic Counter count mode to 104-QUAD-8 count mode */
+	switch (cnt_mode) {
+	case COUNT_MODE_NORMAL:
+		cnt_mode = 0;
+		break;
+	case COUNT_MODE_RANGE_LIMIT:
+		cnt_mode = 1;
+		break;
+	case COUNT_MODE_NON_RECYCLE:
+		cnt_mode = 2;
+		break;
+	case COUNT_MODE_MODULO_N:
+		cnt_mode = 3;
+		break;
+	}
+
+	priv->count_mode[count->id] = cnt_mode;
+
+	/* Set count mode configuration value */
+	mode_cfg = cnt_mode << 1;
+
+	/* Add quadrature mode configuration */
+	if (priv->quadrature_mode[count->id])
+		mode_cfg |= (priv->quadrature_scale[count->id] + 1) << 3;
+
+	/* Load mode configuration to Counter Mode Register */
+	outb(0x20 | mode_cfg, base_offset);
+
+	return 0;
+}
+
+static struct counter_count_enum_ext quad8_cnt_mode_enum = {
+	.items = count_mode_str,
+	.num_items = ARRAY_SIZE(count_mode_str),
+	.get = quad8_count_mode_get,
+	.set = quad8_count_mode_set
+};
+
+static ssize_t quad8_count_direction_read(struct counter_device *counter,
+	struct counter_count *count, void *priv, char *buf)
+{
+	enum count_direction dir;
+
+	quad8_direction_get(counter, count, &dir);
+
+	return scnprintf(buf, PAGE_SIZE, "%s\n", count_direction_str[dir]);
+}
+
+static ssize_t quad8_count_enable_read(struct counter_device *counter,
+	struct counter_count *count, void *private, char *buf)
+{
+	const struct quad8_iio *const priv = counter->priv;
+
+	return scnprintf(buf, PAGE_SIZE, "%u\n", priv->ab_enable[count->id]);
+}
+
+static ssize_t quad8_count_enable_write(struct counter_device *counter,
+	struct counter_count *count, void *private, const char *buf, size_t len)
+{
+	struct quad8_iio *const priv = counter->priv;
+	const int base_offset = priv->base + 2 * count->id;
+	int err;
+	bool ab_enable;
+	unsigned int ior_cfg;
+
+	err = kstrtobool(buf, &ab_enable);
+	if (err)
+		return err;
+
+	priv->ab_enable[count->id] = ab_enable;
+
+	ior_cfg = ab_enable | priv->preset_enable[count->id] << 1;
+
+	/* Load I/O control configuration */
+	outb(0x40 | ior_cfg, base_offset + 1);
+
+	return len;
+}
+
+static int quad8_error_noise_get(struct counter_device *counter,
+	struct counter_count *count, size_t *noise_error)
+{
+	const struct quad8_iio *const priv = counter->priv;
+	const int base_offset = priv->base + 2 * count->id + 1;
+
+	*noise_error = !!(inb(base_offset) & BIT(4));
+
+	return 0;
+}
+
+static struct counter_count_enum_ext quad8_error_noise_enum = {
+	.items = quad8_noise_error_states,
+	.num_items = ARRAY_SIZE(quad8_noise_error_states),
+	.get = quad8_error_noise_get
+};
+
+static ssize_t quad8_count_preset_read(struct counter_device *counter,
+	struct counter_count *count, void *private, char *buf)
+{
+	const struct quad8_iio *const priv = counter->priv;
+
+	return snprintf(buf, PAGE_SIZE, "%u\n", priv->preset[count->id]);
+}
+
+static ssize_t quad8_count_preset_write(struct counter_device *counter,
+	struct counter_count *count, void *private, const char *buf, size_t len)
+{
+	struct quad8_iio *const priv = counter->priv;
+	const int base_offset = priv->base + 2 * count->id;
+	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[count->id] = preset;
+
+	/* Reset Byte Pointer */
+	outb(0x01, base_offset + 1);
+
+	/* Set Preset Register */
+	for (i = 0; i < 3; i++)
+		outb(preset >> (8 * i), base_offset);
+
+	return len;
+}
+
+static ssize_t quad8_count_ceiling_read(struct counter_device *counter,
+	struct counter_count *count, void *private, char *buf)
+{
+	const struct quad8_iio *const priv = counter->priv;
+
+	/* Range Limit and Modulo-N count modes use preset value as ceiling */
+	switch (priv->count_mode[count->id]) {
+	case 1:
+	case 3:
+		return quad8_count_preset_read(counter, count, private, buf);
+	}
+
+	/* By default 0x1FFFFFF (25 bits unsigned) is maximum count */
+	return snprintf(buf, PAGE_SIZE, "33554431\n");
+}
+
+static ssize_t quad8_count_ceiling_write(struct counter_device *counter,
+	struct counter_count *count, void *private, const char *buf, size_t len)
+{
+	struct quad8_iio *const priv = counter->priv;
+
+	/* Range Limit and Modulo-N count modes use preset value as ceiling */
+	switch (priv->count_mode[count->id]) {
+	case 1:
+	case 3:
+		return quad8_count_preset_write(counter, count, private, buf,
+						len);
+	}
+
+	return len;
+}
+
+static ssize_t quad8_count_preset_enable_read(struct counter_device *counter,
+	struct counter_count *count, void *private, char *buf)
+{
+	const struct quad8_iio *const priv = counter->priv;
+
+	return snprintf(buf, PAGE_SIZE, "%u\n",
+		!priv->preset_enable[count->id]);
+}
+
+static ssize_t quad8_count_preset_enable_write(struct counter_device *counter,
+	struct counter_count *count, void *private, const char *buf, size_t len)
+{
+	struct quad8_iio *const priv = counter->priv;
+	const int base_offset = priv->base + 2 * count->id + 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[count->id] = preset_enable;
+
+	ior_cfg = priv->ab_enable[count->id] | (unsigned int)preset_enable << 1;
+
+	/* Load I/O control configuration to Input / Output Control Register */
+	outb(0x40 | ior_cfg, base_offset);
+
+	return len;
+}
+
+static const struct counter_signal_ext quad8_index_ext[] = {
+	COUNTER_SIGNAL_ENUM("index_polarity", &quad8_index_pol_enum),
+	COUNTER_SIGNAL_ENUM_AVAILABLE("index_polarity",	&quad8_index_pol_enum),
+	COUNTER_SIGNAL_ENUM("synchronous_mode", &quad8_syn_mode_enum),
+	COUNTER_SIGNAL_ENUM_AVAILABLE("synchronous_mode", &quad8_syn_mode_enum)
+};
+
+#define	QUAD8_QUAD_SIGNAL(_id, _name) {	\
+	.id = (_id),			\
+	.name = (_name)			\
+}
+
+#define	QUAD8_INDEX_SIGNAL(_id, _name) {	\
+	.id = (_id),				\
+	.name = (_name),			\
+	.ext = quad8_index_ext,			\
+	.num_ext = ARRAY_SIZE(quad8_index_ext)	\
+}
+
+static struct counter_signal quad8_signals[] = {
+	QUAD8_QUAD_SIGNAL(0, "Channel 1 Quadrature A"),
+	QUAD8_QUAD_SIGNAL(1, "Channel 1 Quadrature B"),
+	QUAD8_QUAD_SIGNAL(2, "Channel 2 Quadrature A"),
+	QUAD8_QUAD_SIGNAL(3, "Channel 2 Quadrature B"),
+	QUAD8_QUAD_SIGNAL(4, "Channel 3 Quadrature A"),
+	QUAD8_QUAD_SIGNAL(5, "Channel 3 Quadrature B"),
+	QUAD8_QUAD_SIGNAL(6, "Channel 4 Quadrature A"),
+	QUAD8_QUAD_SIGNAL(7, "Channel 4 Quadrature B"),
+	QUAD8_QUAD_SIGNAL(8, "Channel 5 Quadrature A"),
+	QUAD8_QUAD_SIGNAL(9, "Channel 5 Quadrature B"),
+	QUAD8_QUAD_SIGNAL(10, "Channel 6 Quadrature A"),
+	QUAD8_QUAD_SIGNAL(11, "Channel 6 Quadrature B"),
+	QUAD8_QUAD_SIGNAL(12, "Channel 7 Quadrature A"),
+	QUAD8_QUAD_SIGNAL(13, "Channel 7 Quadrature B"),
+	QUAD8_QUAD_SIGNAL(14, "Channel 8 Quadrature A"),
+	QUAD8_QUAD_SIGNAL(15, "Channel 8 Quadrature B"),
+	QUAD8_INDEX_SIGNAL(16, "Channel 1 Index"),
+	QUAD8_INDEX_SIGNAL(17, "Channel 2 Index"),
+	QUAD8_INDEX_SIGNAL(18, "Channel 3 Index"),
+	QUAD8_INDEX_SIGNAL(19, "Channel 4 Index"),
+	QUAD8_INDEX_SIGNAL(20, "Channel 5 Index"),
+	QUAD8_INDEX_SIGNAL(21, "Channel 6 Index"),
+	QUAD8_INDEX_SIGNAL(22, "Channel 7 Index"),
+	QUAD8_INDEX_SIGNAL(23, "Channel 8 Index")
+};
+
+#define QUAD8_COUNT_SYNAPSES(_id) {					\
+	{								\
+		.actions_list = quad8_synapse_actions_list,		\
+		.num_actions = ARRAY_SIZE(quad8_synapse_actions_list),	\
+		.signal = quad8_signals + 2 * (_id)			\
+	},								\
+	{								\
+		.actions_list = quad8_synapse_actions_list,		\
+		.num_actions = ARRAY_SIZE(quad8_synapse_actions_list),	\
+		.signal = quad8_signals + 2 * (_id) + 1			\
+	},								\
+	{								\
+		.actions_list = quad8_index_actions_list,		\
+		.num_actions = ARRAY_SIZE(quad8_index_actions_list),	\
+		.signal = quad8_signals + 2 * (_id) + 16		\
+	}								\
+}
+
+static struct counter_synapse quad8_count_synapses[][3] = {
+	QUAD8_COUNT_SYNAPSES(0), QUAD8_COUNT_SYNAPSES(1),
+	QUAD8_COUNT_SYNAPSES(2), QUAD8_COUNT_SYNAPSES(3),
+	QUAD8_COUNT_SYNAPSES(4), QUAD8_COUNT_SYNAPSES(5),
+	QUAD8_COUNT_SYNAPSES(6), QUAD8_COUNT_SYNAPSES(7)
+};
+
+static const struct counter_count_ext quad8_count_ext[] = {
+	{
+		.name = "ceiling",
+		.read = quad8_count_ceiling_read,
+		.write = quad8_count_ceiling_write
+	},
+	{
+		.name = "floor",
+		.read = quad8_count_floor_read
+	},
+	COUNTER_COUNT_ENUM("count_mode", &quad8_cnt_mode_enum),
+	COUNTER_COUNT_ENUM_AVAILABLE("count_mode", &quad8_cnt_mode_enum),
+	{
+		.name = "direction",
+		.read = quad8_count_direction_read
+	},
+	{
+		.name = "enable",
+		.read = quad8_count_enable_read,
+		.write = quad8_count_enable_write
+	},
+	COUNTER_COUNT_ENUM("error_noise", &quad8_error_noise_enum),
+	COUNTER_COUNT_ENUM_AVAILABLE("error_noise", &quad8_error_noise_enum),
+	{
+		.name = "preset",
+		.read = quad8_count_preset_read,
+		.write = quad8_count_preset_write
+	},
+	{
+		.name = "preset_enable",
+		.read = quad8_count_preset_enable_read,
+		.write = quad8_count_preset_enable_write
+	}
+};
+
+#define QUAD8_COUNT(_id, _cntname) {					\
+	.id = (_id),							\
+	.name = (_cntname),						\
+	.functions_list = quad8_count_functions_list,			\
+	.num_functions = ARRAY_SIZE(quad8_count_functions_list),	\
+	.synapses = quad8_count_synapses[(_id)],			\
+	.num_synapses =	2,						\
+	.ext = quad8_count_ext,						\
+	.num_ext = ARRAY_SIZE(quad8_count_ext)				\
+}
+
+static struct counter_count quad8_counts[] = {
+	QUAD8_COUNT(0, "Channel 1 Count"),
+	QUAD8_COUNT(1, "Channel 2 Count"),
+	QUAD8_COUNT(2, "Channel 3 Count"),
+	QUAD8_COUNT(3, "Channel 4 Count"),
+	QUAD8_COUNT(4, "Channel 5 Count"),
+	QUAD8_COUNT(5, "Channel 6 Count"),
+	QUAD8_COUNT(6, "Channel 7 Count"),
+	QUAD8_COUNT(7, "Channel 8 Count")
+};
+
+static int quad8_probe(struct device *dev, unsigned int id)
+{
+	struct iio_dev *indio_dev;
+	struct quad8_iio *quad8iio;
+	int i, j;
+	unsigned int base_offset;
+	int err;
+
+	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;
+	}
+
+	/* Allocate IIO device; this also allocates driver data structure */
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*quad8iio));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	/* Initialize IIO device */
+	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;
+
+	/* Initialize Counter device and driver data */
+	quad8iio = iio_priv(indio_dev);
+	quad8iio->counter.name = dev_name(dev);
+	quad8iio->counter.parent = dev;
+	quad8iio->counter.ops = &quad8_ops;
+	quad8iio->counter.counts = quad8_counts;
+	quad8iio->counter.num_counts = ARRAY_SIZE(quad8_counts);
+	quad8iio->counter.signals = quad8_signals;
+	quad8iio->counter.num_signals = ARRAY_SIZE(quad8_signals);
+	quad8iio->counter.priv = quad8iio;
+	quad8iio->base = base[id];
+
+	/* Reset all counters and disable interrupt function */
+	outb(0x01, base[id] + 0x11);
+	/* Set initial configuration for all counters */
+	for (i = 0; i < QUAD8_NUM_COUNTERS; i++) {
+		base_offset = base[id] + 2 * i;
+		/* Reset Byte Pointer */
+		outb(0x01, base_offset + 1);
+		/* Reset Preset Register */
+		for (j = 0; j < 3; j++)
+			outb(0x00, base_offset);
+		/* Reset Borrow, Carry, Compare, and Sign flags */
+		outb(0x04, base_offset + 1);
+		/* Reset Error flag */
+		outb(0x06, base_offset + 1);
+		/* Binary encoding; Normal count; non-quadrature mode */
+		outb(0x20, base_offset + 1);
+		/* Disable A and B inputs; preset on index; FLG1 as Carry */
+		outb(0x40, base_offset + 1);
+		/* Disable index function; negative index polarity */
+		outb(0x60, base_offset + 1);
+	}
+	/* Enable all counters */
+	outb(0x00, base[id] + 0x11);
+
+	/* Register IIO device */
+	err = devm_iio_device_register(dev, indio_dev);
+	if (err)
+		return err;
+
+	/* Register Counter device */
+	return devm_counter_register(dev, &quad8iio->counter);
+}
+
+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/counter/Kconfig b/drivers/counter/Kconfig
index 65fa92abd5a4..73f03372484f 100644
--- a/drivers/counter/Kconfig
+++ b/drivers/counter/Kconfig
@@ -16,3 +16,24 @@ menuconfig COUNTER
 	  consumption. The Generic Counter interface enables drivers to support
 	  and expose a common set of components and functionality present in
 	  counter devices.
+
+if COUNTER
+
+config 104_QUAD_8
+	tristate "ACCES 104-QUAD-8 driver"
+	depends on PC104 && X86 && IIO
+	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.
+
+endif # COUNTER
diff --git a/drivers/counter/Makefile b/drivers/counter/Makefile
index ad1ba7109cdc..23a4f6263e45 100644
--- a/drivers/counter/Makefile
+++ b/drivers/counter/Makefile
@@ -6,3 +6,5 @@
 
 obj-$(CONFIG_COUNTER) += counter.o
 counter-y := generic-counter.o
+
+obj-$(CONFIG_104_QUAD_8)	+= 104-quad-8.o
diff --git a/drivers/iio/counter/104-quad-8.c b/drivers/iio/counter/104-quad-8.c
deleted file mode 100644
index b56985078d8c..000000000000
--- a/drivers/iio/counter/104-quad-8.c
+++ /dev/null
@@ -1,596 +0,0 @@
-/*
- * IIO driver for the ACCES 104-QUAD-8
- * Copyright (C) 2016 William Breathitt Gray
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License, version 2, as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * 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;
-};
-
-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 + 0x16) & BIT(chan->channel));
-			return IIO_VAL_INT;
-		}
-
-		flags = inb(base_offset + 1);
-		borrow = flags & BIT(0);
-		carry = !!(flags & BIT(1));
-
-		/* Borrow XOR Carry effectively doubles count range */
-		*val = (borrow ^ carry) << 24;
-
-		/* Reset Byte Pointer; transfer Counter to Output Latch */
-		outb(0x11, 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(0x01, 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(0x08, base_offset + 1);
-
-		/* Reset Byte Pointer */
-		outb(0x01, 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(0x02, base_offset + 1);
-		/* Reset Error flag */
-		outb(0x06, 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(0x40 | 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(0x01, 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(0x40 | 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) & BIT(4));
-}
-
-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) & BIT(5));
-}
-
-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(0x20 | 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(0x60 | 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(0x20 | 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(0x60 | 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(0x01, base[id] + 0x11);
-	/* Set initial configuration for all counters */
-	for (i = 0; i < QUAD8_NUM_COUNTERS; i++) {
-		base_offset = base[id] + 2 * i;
-		/* Reset Byte Pointer */
-		outb(0x01, base_offset + 1);
-		/* Reset Preset Register */
-		for (j = 0; j < 3; j++)
-			outb(0x00, base_offset);
-		/* Reset Borrow, Carry, Compare, and Sign flags */
-		outb(0x04, base_offset + 1);
-		/* Reset Error flag */
-		outb(0x06, base_offset + 1);
-		/* Binary encoding; Normal count; non-quadrature mode */
-		outb(0x20, base_offset + 1);
-		/* Disable A and B inputs; preset on index; FLG1 as Carry */
-		outb(0x40, base_offset + 1);
-		/* Disable index function; negative index polarity */
-		outb(0x60, base_offset + 1);
-	}
-	/* Enable all counters */
-	outb(0x00, base[id] + 0x11);
-
-	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
