drivers/iio/adc/adi-axi-adc.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Analog Devices Generic AXI ADC IP core
  * Link: https://wiki.analog.com/resources/fpga/docs/axi_adc_ip
  *
  * Copyright 2012-2020 Analog Devices Inc.
  */

 #include <linux/bitfield.h>
 #include <linux/clk.h>
 #include <linux/io.h>
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/property.h>
 #include <linux/regmap.h>
 #include <linux/slab.h>

 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
 #include <linux/iio/buffer.h>
 #include <linux/iio/buffer-dmaengine.h>

 #include <linux/fpga/adi-axi-common.h>
 #include <linux/iio/adc/adi-axi-adc.h>

 /*
  * Register definitions:
  *   https://wiki.analog.com/resources/fpga/docs/axi_adc_ip#register_map
  */

 /* ADC controls */

 #define ADI_AXI_REG_RSTN			0x0040
 #define   ADI_AXI_REG_RSTN_CE_N			BIT(2)
 #define   ADI_AXI_REG_RSTN_MMCM_RSTN		BIT(1)
 #define   ADI_AXI_REG_RSTN_RSTN			BIT(0)

 /* ADC Channel controls */

 #define ADI_AXI_REG_CHAN_CTRL(c)		(0x0400 + (c) * 0x40)
 #define   ADI_AXI_REG_CHAN_CTRL_LB_OWR		BIT(11)
 #define   ADI_AXI_REG_CHAN_CTRL_PN_SEL_OWR	BIT(10)
 #define   ADI_AXI_REG_CHAN_CTRL_IQCOR_EN	BIT(9)
 #define   ADI_AXI_REG_CHAN_CTRL_DCFILT_EN	BIT(8)
 #define   ADI_AXI_REG_CHAN_CTRL_FMT_SIGNEXT	BIT(6)
 #define   ADI_AXI_REG_CHAN_CTRL_FMT_TYPE	BIT(5)
 #define   ADI_AXI_REG_CHAN_CTRL_FMT_EN		BIT(4)
 #define   ADI_AXI_REG_CHAN_CTRL_PN_TYPE_OWR	BIT(1)
 #define   ADI_AXI_REG_CHAN_CTRL_ENABLE		BIT(0)

 #define ADI_AXI_REG_CHAN_CTRL_DEFAULTS		\
 	(ADI_AXI_REG_CHAN_CTRL_FMT_SIGNEXT |	\
 	 ADI_AXI_REG_CHAN_CTRL_FMT_EN |		\
 	 ADI_AXI_REG_CHAN_CTRL_ENABLE)

 struct adi_axi_adc_core_info {
 	unsigned int				version;
 };

 struct adi_axi_adc_state {
 	struct mutex				lock;

 	struct adi_axi_adc_client		*client;
 	struct regmap				*regmap;
 };

 struct adi_axi_adc_client {
 	struct list_head			entry;
 	struct adi_axi_adc_conv			conv;
 	struct adi_axi_adc_state		*state;
 	struct device				*dev;
 	const struct adi_axi_adc_core_info	*info;
 };

 static LIST_HEAD(registered_clients);
 static DEFINE_MUTEX(registered_clients_lock);

 static struct adi_axi_adc_client *conv_to_client(struct adi_axi_adc_conv *conv)
 {
 	return container_of(conv, struct adi_axi_adc_client, conv);
 }

 void *adi_axi_adc_conv_priv(struct adi_axi_adc_conv *conv)
 {
 	struct adi_axi_adc_client *cl = conv_to_client(conv);

 	return (char *)cl + ALIGN(sizeof(struct adi_axi_adc_client),
 				  IIO_DMA_MINALIGN);
 }
 EXPORT_SYMBOL_NS_GPL(adi_axi_adc_conv_priv, IIO_ADI_AXI);

 static int adi_axi_adc_config_dma_buffer(struct device *dev,
 					 struct iio_dev *indio_dev)
 {
 	const char *dma_name;

 	if (!device_property_present(dev, "dmas"))
 		return 0;

 	if (device_property_read_string(dev, "dma-names", &dma_name))
 		dma_name = "rx";

 	return devm_iio_dmaengine_buffer_setup(indio_dev->dev.parent,
 					       indio_dev, dma_name);
 }

 static int adi_axi_adc_read_raw(struct iio_dev *indio_dev,
 				struct iio_chan_spec const *chan,
 				int *val, int *val2, long mask)
 {
 	struct adi_axi_adc_state *st = iio_priv(indio_dev);
 	struct adi_axi_adc_conv *conv = &st->client->conv;

 	if (!conv->read_raw)
 		return -EOPNOTSUPP;

 	return conv->read_raw(conv, chan, val, val2, mask);
 }

 static int adi_axi_adc_write_raw(struct iio_dev *indio_dev,
 				 struct iio_chan_spec const *chan,
 				 int val, int val2, long mask)
 {
 	struct adi_axi_adc_state *st = iio_priv(indio_dev);
 	struct adi_axi_adc_conv *conv = &st->client->conv;

 	if (!conv->write_raw)
 		return -EOPNOTSUPP;

 	return conv->write_raw(conv, chan, val, val2, mask);
 }

 static int adi_axi_adc_read_avail(struct iio_dev *indio_dev,
 				  struct iio_chan_spec const *chan,
 				  const int **vals, int *type, int *length,
 				  long mask)
 {
 	struct adi_axi_adc_state *st = iio_priv(indio_dev);
 	struct adi_axi_adc_conv *conv = &st->client->conv;

 	if (!conv->read_avail)
 		return -EOPNOTSUPP;

 	return conv->read_avail(conv, chan, vals, type, length, mask);
 }

 static int adi_axi_adc_update_scan_mode(struct iio_dev *indio_dev,
 					const unsigned long *scan_mask)
 {
 	struct adi_axi_adc_state *st = iio_priv(indio_dev);
 	struct adi_axi_adc_conv *conv = &st->client->conv;
 	unsigned int i;
 	int ret;

 	for (i = 0; i < conv->chip_info->num_channels; i++) {
 		if (test_bit(i, scan_mask))
 			ret = regmap_set_bits(st->regmap,
 					      ADI_AXI_REG_CHAN_CTRL(i),
 					      ADI_AXI_REG_CHAN_CTRL_ENABLE);
 		else
 			ret = regmap_clear_bits(st->regmap,
 						ADI_AXI_REG_CHAN_CTRL(i),
 						ADI_AXI_REG_CHAN_CTRL_ENABLE);
 		if (ret)
 			return ret;
 	}

 	return 0;
 }

 static struct adi_axi_adc_conv *adi_axi_adc_conv_register(struct device *dev,
 							  size_t sizeof_priv)
 {
 	struct adi_axi_adc_client *cl;
 	size_t alloc_size;

 	alloc_size = ALIGN(sizeof(struct adi_axi_adc_client), IIO_DMA_MINALIGN);
 	if (sizeof_priv)
 		alloc_size += ALIGN(sizeof_priv, IIO_DMA_MINALIGN);

 	cl = kzalloc(alloc_size, GFP_KERNEL);
 	if (!cl)
 		return ERR_PTR(-ENOMEM);

 	mutex_lock(&registered_clients_lock);

 	cl->dev = get_device(dev);

 	list_add_tail(&cl->entry, &registered_clients);

 	mutex_unlock(&registered_clients_lock);

 	return &cl->conv;
 }

 static void adi_axi_adc_conv_unregister(struct adi_axi_adc_conv *conv)
 {
 	struct adi_axi_adc_client *cl = conv_to_client(conv);

 	mutex_lock(&registered_clients_lock);

 	list_del(&cl->entry);
 	put_device(cl->dev);

 	mutex_unlock(&registered_clients_lock);

 	kfree(cl);
 }

 static void devm_adi_axi_adc_conv_release(void *conv)
 {
 	adi_axi_adc_conv_unregister(conv);
 }

 struct adi_axi_adc_conv *devm_adi_axi_adc_conv_register(struct device *dev,
 							size_t sizeof_priv)
 {
 	struct adi_axi_adc_conv *conv;
 	int ret;

 	conv = adi_axi_adc_conv_register(dev, sizeof_priv);
 	if (IS_ERR(conv))
 		return conv;

 	ret = devm_add_action_or_reset(dev, devm_adi_axi_adc_conv_release,
 				       conv);
 	if (ret)
 		return ERR_PTR(ret);

 	return conv;
 }
 EXPORT_SYMBOL_NS_GPL(devm_adi_axi_adc_conv_register, IIO_ADI_AXI);

 static const struct iio_info adi_axi_adc_info = {
 	.read_raw = &adi_axi_adc_read_raw,
 	.write_raw = &adi_axi_adc_write_raw,
 	.update_scan_mode = &adi_axi_adc_update_scan_mode,
 	.read_avail = &adi_axi_adc_read_avail,
 };

 static const struct adi_axi_adc_core_info adi_axi_adc_10_0_a_info = {
 	.version = ADI_AXI_PCORE_VER(10, 0, 'a'),
 };

 static struct adi_axi_adc_client *adi_axi_adc_attach_client(struct device *dev)
 {
 	const struct adi_axi_adc_core_info *info;
 	struct adi_axi_adc_client *cl;
 	struct device_node *cln;

 	info = of_device_get_match_data(dev);
 	if (!info)
 		return ERR_PTR(-ENODEV);

 	cln = of_parse_phandle(dev->of_node, "adi,adc-dev", 0);
 	if (!cln) {
 		dev_err(dev, "No 'adi,adc-dev' node defined\n");
 		return ERR_PTR(-ENODEV);
 	}

 	mutex_lock(&registered_clients_lock);

 	list_for_each_entry(cl, &registered_clients, entry) {
 		if (!cl->dev)
 			continue;

 		if (cl->dev->of_node != cln)
 			continue;

 		if (!try_module_get(cl->dev->driver->owner)) {
 			mutex_unlock(&registered_clients_lock);
 			of_node_put(cln);
 			return ERR_PTR(-ENODEV);
 		}

 		get_device(cl->dev);
 		cl->info = info;
 		mutex_unlock(&registered_clients_lock);
 		of_node_put(cln);
 		return cl;
 	}

 	mutex_unlock(&registered_clients_lock);
 	of_node_put(cln);

 	return ERR_PTR(-EPROBE_DEFER);
 }

 static int adi_axi_adc_setup_channels(struct device *dev,
 				      struct adi_axi_adc_state *st)
 {
 	struct adi_axi_adc_conv *conv = &st->client->conv;
 	int i, ret;

 	if (conv->preenable_setup) {
 		ret = conv->preenable_setup(conv);
 		if (ret)
 			return ret;
 	}

 	for (i = 0; i < conv->chip_info->num_channels; i++) {
 		ret = regmap_write(st->regmap, ADI_AXI_REG_CHAN_CTRL(i),
 				   ADI_AXI_REG_CHAN_CTRL_DEFAULTS);
 		if (ret)
 			return ret;
 	}

 	return 0;
 }

 static int axi_adc_reset(struct adi_axi_adc_state *st)
 {
 	int ret;

 	ret = regmap_write(st->regmap, ADI_AXI_REG_RSTN, 0);
 	if (ret)
 		return ret;

 	mdelay(10);
 	ret = regmap_write(st->regmap, ADI_AXI_REG_RSTN,
 			   ADI_AXI_REG_RSTN_MMCM_RSTN);
 	if (ret)
 		return ret;

 	mdelay(10);
 	return regmap_write(st->regmap, ADI_AXI_REG_RSTN,
 			    ADI_AXI_REG_RSTN_RSTN | ADI_AXI_REG_RSTN_MMCM_RSTN);
 }

 static void adi_axi_adc_cleanup(void *data)
 {
 	struct adi_axi_adc_client *cl = data;

 	put_device(cl->dev);
 	module_put(cl->dev->driver->owner);
 }

 static const struct regmap_config axi_adc_regmap_config = {
 	.val_bits = 32,
 	.reg_bits = 32,
 	.reg_stride = 4,
 	.max_register = 0x0800,
 };

 static int adi_axi_adc_probe(struct platform_device *pdev)
 {
 	struct adi_axi_adc_conv *conv;
 	struct iio_dev *indio_dev;
 	struct adi_axi_adc_client *cl;
 	struct adi_axi_adc_state *st;
 	void __iomem *base;
 	unsigned int ver;
 	int ret;

 	cl = adi_axi_adc_attach_client(&pdev->dev);
 	if (IS_ERR(cl))
 		return PTR_ERR(cl);

 	ret = devm_add_action_or_reset(&pdev->dev, adi_axi_adc_cleanup, cl);
 	if (ret)
 		return ret;

 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*st));
 	if (indio_dev == NULL)
 		return -ENOMEM;

 	st = iio_priv(indio_dev);
 	st->client = cl;
 	cl->state = st;
 	mutex_init(&st->lock);

 	base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(base))
 		return PTR_ERR(base);

 	st->regmap = devm_regmap_init_mmio(&pdev->dev, base,
 					   &axi_adc_regmap_config);
 	if (IS_ERR(st->regmap))
 		return PTR_ERR(st->regmap);

 	conv = &st->client->conv;

 	ret = axi_adc_reset(st);
 	if (ret)
 		return ret;

 	ret = regmap_read(st->regmap, ADI_AXI_REG_VERSION, &ver);
 	if (ret)
 		return ret;

 	if (cl->info->version > ver) {
 		dev_err(&pdev->dev,
 			"IP core version is too old. Expected %d.%.2d.%c, Reported %d.%.2d.%c\n",
 			ADI_AXI_PCORE_VER_MAJOR(cl->info->version),
 			ADI_AXI_PCORE_VER_MINOR(cl->info->version),
 			ADI_AXI_PCORE_VER_PATCH(cl->info->version),
 			ADI_AXI_PCORE_VER_MAJOR(ver),
 			ADI_AXI_PCORE_VER_MINOR(ver),
 			ADI_AXI_PCORE_VER_PATCH(ver));
 		return -ENODEV;
 	}

 	indio_dev->info = &adi_axi_adc_info;
 	indio_dev->name = "adi-axi-adc";
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->num_channels = conv->chip_info->num_channels;
 	indio_dev->channels = conv->chip_info->channels;

 	ret = adi_axi_adc_config_dma_buffer(&pdev->dev, indio_dev);
 	if (ret)
 		return ret;

 	ret = adi_axi_adc_setup_channels(&pdev->dev, st);
 	if (ret)
 		return ret;

 	ret = devm_iio_device_register(&pdev->dev, indio_dev);
 	if (ret)
 		return ret;

 	dev_info(&pdev->dev, "AXI ADC IP core (%d.%.2d.%c) probed\n",
 		 ADI_AXI_PCORE_VER_MAJOR(ver),
 		 ADI_AXI_PCORE_VER_MINOR(ver),
 		 ADI_AXI_PCORE_VER_PATCH(ver));

 	return 0;
 }

 /* Match table for of_platform binding */
 static const struct of_device_id adi_axi_adc_of_match[] = {
 	{ .compatible = "adi,axi-adc-10.0.a", .data = &adi_axi_adc_10_0_a_info },
 	{ /* end of list */ }
 };
 MODULE_DEVICE_TABLE(of, adi_axi_adc_of_match);

 static struct platform_driver adi_axi_adc_driver = {
 	.driver = {
 		.name = KBUILD_MODNAME,
 		.of_match_table = adi_axi_adc_of_match,
 	},
 	.probe = adi_axi_adc_probe,
 };
 module_platform_driver(adi_axi_adc_driver);

 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
 MODULE_DESCRIPTION("Analog Devices Generic AXI ADC IP core driver");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* Analog Devices Generic AXI ADC IP core
	* Link: https://wiki.analog.com/resources/fpga/docs/axi_adc_ip
	*
	* Copyright 2012-2020 Analog Devices Inc.
	*/

	#include <linux/bitfield.h>
	#include <linux/clk.h>
	#include <linux/io.h>
	#include <linux/delay.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/platform_device.h>
	#include <linux/property.h>
	#include <linux/regmap.h>
	#include <linux/slab.h>

	#include <linux/iio/iio.h>
	#include <linux/iio/sysfs.h>
	#include <linux/iio/buffer.h>
	#include <linux/iio/buffer-dmaengine.h>

	#include <linux/fpga/adi-axi-common.h>
	#include <linux/iio/adc/adi-axi-adc.h>

	/*
	* Register definitions:
	* https://wiki.analog.com/resources/fpga/docs/axi_adc_ip#register_map
	*/

	/* ADC controls */

	#define ADI_AXI_REG_RSTN 0x0040
	#define ADI_AXI_REG_RSTN_CE_N BIT(2)
	#define ADI_AXI_REG_RSTN_MMCM_RSTN BIT(1)
	#define ADI_AXI_REG_RSTN_RSTN BIT(0)

	/* ADC Channel controls */

	#define ADI_AXI_REG_CHAN_CTRL(c) (0x0400 + (c) * 0x40)
	#define ADI_AXI_REG_CHAN_CTRL_LB_OWR BIT(11)
	#define ADI_AXI_REG_CHAN_CTRL_PN_SEL_OWR BIT(10)
	#define ADI_AXI_REG_CHAN_CTRL_IQCOR_EN BIT(9)
	#define ADI_AXI_REG_CHAN_CTRL_DCFILT_EN BIT(8)
	#define ADI_AXI_REG_CHAN_CTRL_FMT_SIGNEXT BIT(6)
	#define ADI_AXI_REG_CHAN_CTRL_FMT_TYPE BIT(5)
	#define ADI_AXI_REG_CHAN_CTRL_FMT_EN BIT(4)
	#define ADI_AXI_REG_CHAN_CTRL_PN_TYPE_OWR BIT(1)
	#define ADI_AXI_REG_CHAN_CTRL_ENABLE BIT(0)

	#define ADI_AXI_REG_CHAN_CTRL_DEFAULTS \
	(ADI_AXI_REG_CHAN_CTRL_FMT_SIGNEXT \| \
	ADI_AXI_REG_CHAN_CTRL_FMT_EN \| \
	ADI_AXI_REG_CHAN_CTRL_ENABLE)

	struct adi_axi_adc_core_info {
	unsigned int version;
	};

	struct adi_axi_adc_state {
	struct mutex lock;

	struct adi_axi_adc_client *client;
	struct regmap *regmap;
	};

	struct adi_axi_adc_client {
	struct list_head entry;
	struct adi_axi_adc_conv conv;
	struct adi_axi_adc_state *state;
	struct device *dev;
	const struct adi_axi_adc_core_info *info;
	};

	static LIST_HEAD(registered_clients);
	static DEFINE_MUTEX(registered_clients_lock);

	static struct adi_axi_adc_client conv_to_client(struct adi_axi_adc_conv conv)
	{
	return container_of(conv, struct adi_axi_adc_client, conv);
	}

	void adi_axi_adc_conv_priv(struct adi_axi_adc_conv conv)
	{
	struct adi_axi_adc_client *cl = conv_to_client(conv);

	return (char *)cl + ALIGN(sizeof(struct adi_axi_adc_client),
	IIO_DMA_MINALIGN);
	}
	EXPORT_SYMBOL_NS_GPL(adi_axi_adc_conv_priv, IIO_ADI_AXI);

	static int adi_axi_adc_config_dma_buffer(struct device *dev,
	struct iio_dev *indio_dev)
	{
	const char *dma_name;

	if (!device_property_present(dev, "dmas"))
	return 0;

	if (device_property_read_string(dev, "dma-names", &dma_name))
	dma_name = "rx";

	return devm_iio_dmaengine_buffer_setup(indio_dev->dev.parent,
	indio_dev, dma_name);
	}

	static int adi_axi_adc_read_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int val, int val2, long mask)
	{
	struct adi_axi_adc_state *st = iio_priv(indio_dev);
	struct adi_axi_adc_conv *conv = &st->client->conv;

	if (!conv->read_raw)
	return -EOPNOTSUPP;

	return conv->read_raw(conv, chan, val, val2, mask);
	}

	static int adi_axi_adc_write_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int val, int val2, long mask)
	{
	struct adi_axi_adc_state *st = iio_priv(indio_dev);
	struct adi_axi_adc_conv *conv = &st->client->conv;

	if (!conv->write_raw)
	return -EOPNOTSUPP;

	return conv->write_raw(conv, chan, val, val2, mask);
	}

	static int adi_axi_adc_read_avail(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	const int *vals, int type, int *length,
	long mask)
	{
	struct adi_axi_adc_state *st = iio_priv(indio_dev);
	struct adi_axi_adc_conv *conv = &st->client->conv;

	if (!conv->read_avail)
	return -EOPNOTSUPP;

	return conv->read_avail(conv, chan, vals, type, length, mask);
	}

	static int adi_axi_adc_update_scan_mode(struct iio_dev *indio_dev,
	const unsigned long *scan_mask)
	{
	struct adi_axi_adc_state *st = iio_priv(indio_dev);
	struct adi_axi_adc_conv *conv = &st->client->conv;
	unsigned int i;
	int ret;

	for (i = 0; i < conv->chip_info->num_channels; i++) {
	if (test_bit(i, scan_mask))
	ret = regmap_set_bits(st->regmap,
	ADI_AXI_REG_CHAN_CTRL(i),
	ADI_AXI_REG_CHAN_CTRL_ENABLE);
	else
	ret = regmap_clear_bits(st->regmap,
	ADI_AXI_REG_CHAN_CTRL(i),
	ADI_AXI_REG_CHAN_CTRL_ENABLE);
	if (ret)
	return ret;
	}

	return 0;
	}

	static struct adi_axi_adc_conv adi_axi_adc_conv_register(struct device dev,
	size_t sizeof_priv)
	{
	struct adi_axi_adc_client *cl;
	size_t alloc_size;

	alloc_size = ALIGN(sizeof(struct adi_axi_adc_client), IIO_DMA_MINALIGN);
	if (sizeof_priv)
	alloc_size += ALIGN(sizeof_priv, IIO_DMA_MINALIGN);

	cl = kzalloc(alloc_size, GFP_KERNEL);
	if (!cl)
	return ERR_PTR(-ENOMEM);

	mutex_lock(&registered_clients_lock);

	cl->dev = get_device(dev);

	list_add_tail(&cl->entry, &registered_clients);

	mutex_unlock(&registered_clients_lock);

	return &cl->conv;
	}

	static void adi_axi_adc_conv_unregister(struct adi_axi_adc_conv *conv)
	{
	struct adi_axi_adc_client *cl = conv_to_client(conv);

	mutex_lock(&registered_clients_lock);

	list_del(&cl->entry);
	put_device(cl->dev);

	mutex_unlock(&registered_clients_lock);

	kfree(cl);
	}

	static void devm_adi_axi_adc_conv_release(void *conv)
	{
	adi_axi_adc_conv_unregister(conv);
	}

	struct adi_axi_adc_conv devm_adi_axi_adc_conv_register(struct device dev,
	size_t sizeof_priv)
	{
	struct adi_axi_adc_conv *conv;
	int ret;

	conv = adi_axi_adc_conv_register(dev, sizeof_priv);
	if (IS_ERR(conv))
	return conv;

	ret = devm_add_action_or_reset(dev, devm_adi_axi_adc_conv_release,
	conv);
	if (ret)
	return ERR_PTR(ret);

	return conv;
	}
	EXPORT_SYMBOL_NS_GPL(devm_adi_axi_adc_conv_register, IIO_ADI_AXI);

	static const struct iio_info adi_axi_adc_info = {
	.read_raw = &adi_axi_adc_read_raw,
	.write_raw = &adi_axi_adc_write_raw,
	.update_scan_mode = &adi_axi_adc_update_scan_mode,
	.read_avail = &adi_axi_adc_read_avail,
	};

	static const struct adi_axi_adc_core_info adi_axi_adc_10_0_a_info = {
	.version = ADI_AXI_PCORE_VER(10, 0, 'a'),
	};

	static struct adi_axi_adc_client adi_axi_adc_attach_client(struct device dev)
	{
	const struct adi_axi_adc_core_info *info;
	struct adi_axi_adc_client *cl;
	struct device_node *cln;

	info = of_device_get_match_data(dev);
	if (!info)
	return ERR_PTR(-ENODEV);

	cln = of_parse_phandle(dev->of_node, "adi,adc-dev", 0);
	if (!cln) {
	dev_err(dev, "No 'adi,adc-dev' node defined\n");
	return ERR_PTR(-ENODEV);
	}

	mutex_lock(&registered_clients_lock);

	list_for_each_entry(cl, &registered_clients, entry) {
	if (!cl->dev)
	continue;

	if (cl->dev->of_node != cln)
	continue;

	if (!try_module_get(cl->dev->driver->owner)) {
	mutex_unlock(&registered_clients_lock);
	of_node_put(cln);
	return ERR_PTR(-ENODEV);
	}

	get_device(cl->dev);
	cl->info = info;
	mutex_unlock(&registered_clients_lock);
	of_node_put(cln);
	return cl;
	}

	mutex_unlock(&registered_clients_lock);
	of_node_put(cln);

	return ERR_PTR(-EPROBE_DEFER);
	}

	static int adi_axi_adc_setup_channels(struct device *dev,
	struct adi_axi_adc_state *st)
	{
	struct adi_axi_adc_conv *conv = &st->client->conv;
	int i, ret;

	if (conv->preenable_setup) {
	ret = conv->preenable_setup(conv);
	if (ret)
	return ret;
	}

	for (i = 0; i < conv->chip_info->num_channels; i++) {
	ret = regmap_write(st->regmap, ADI_AXI_REG_CHAN_CTRL(i),
	ADI_AXI_REG_CHAN_CTRL_DEFAULTS);
	if (ret)
	return ret;
	}

	return 0;
	}

	static int axi_adc_reset(struct adi_axi_adc_state *st)
	{
	int ret;

	ret = regmap_write(st->regmap, ADI_AXI_REG_RSTN, 0);
	if (ret)
	return ret;

	mdelay(10);
	ret = regmap_write(st->regmap, ADI_AXI_REG_RSTN,
	ADI_AXI_REG_RSTN_MMCM_RSTN);
	if (ret)
	return ret;

	mdelay(10);
	return regmap_write(st->regmap, ADI_AXI_REG_RSTN,
	ADI_AXI_REG_RSTN_RSTN \| ADI_AXI_REG_RSTN_MMCM_RSTN);
	}

	static void adi_axi_adc_cleanup(void *data)
	{
	struct adi_axi_adc_client *cl = data;

	put_device(cl->dev);
	module_put(cl->dev->driver->owner);
	}

	static const struct regmap_config axi_adc_regmap_config = {
	.val_bits = 32,
	.reg_bits = 32,
	.reg_stride = 4,
	.max_register = 0x0800,
	};

	static int adi_axi_adc_probe(struct platform_device *pdev)
	{
	struct adi_axi_adc_conv *conv;
	struct iio_dev *indio_dev;
	struct adi_axi_adc_client *cl;
	struct adi_axi_adc_state *st;
	void __iomem *base;
	unsigned int ver;
	int ret;

	cl = adi_axi_adc_attach_client(&pdev->dev);
	if (IS_ERR(cl))
	return PTR_ERR(cl);

	ret = devm_add_action_or_reset(&pdev->dev, adi_axi_adc_cleanup, cl);
	if (ret)
	return ret;

	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*st));
	if (indio_dev == NULL)
	return -ENOMEM;

	st = iio_priv(indio_dev);
	st->client = cl;
	cl->state = st;
	mutex_init(&st->lock);

	base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(base))
	return PTR_ERR(base);

	st->regmap = devm_regmap_init_mmio(&pdev->dev, base,
	&axi_adc_regmap_config);
	if (IS_ERR(st->regmap))
	return PTR_ERR(st->regmap);

	conv = &st->client->conv;

	ret = axi_adc_reset(st);
	if (ret)
	return ret;

	ret = regmap_read(st->regmap, ADI_AXI_REG_VERSION, &ver);
	if (ret)
	return ret;

	if (cl->info->version > ver) {
	dev_err(&pdev->dev,
	"IP core version is too old. Expected %d.%.2d.%c, Reported %d.%.2d.%c\n",
	ADI_AXI_PCORE_VER_MAJOR(cl->info->version),
	ADI_AXI_PCORE_VER_MINOR(cl->info->version),
	ADI_AXI_PCORE_VER_PATCH(cl->info->version),
	ADI_AXI_PCORE_VER_MAJOR(ver),
	ADI_AXI_PCORE_VER_MINOR(ver),
	ADI_AXI_PCORE_VER_PATCH(ver));
	return -ENODEV;
	}

	indio_dev->info = &adi_axi_adc_info;
	indio_dev->name = "adi-axi-adc";
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->num_channels = conv->chip_info->num_channels;
	indio_dev->channels = conv->chip_info->channels;

	ret = adi_axi_adc_config_dma_buffer(&pdev->dev, indio_dev);
	if (ret)
	return ret;

	ret = adi_axi_adc_setup_channels(&pdev->dev, st);
	if (ret)
	return ret;

	ret = devm_iio_device_register(&pdev->dev, indio_dev);
	if (ret)
	return ret;

	dev_info(&pdev->dev, "AXI ADC IP core (%d.%.2d.%c) probed\n",
	ADI_AXI_PCORE_VER_MAJOR(ver),
	ADI_AXI_PCORE_VER_MINOR(ver),
	ADI_AXI_PCORE_VER_PATCH(ver));

	return 0;
	}

	/* Match table for of_platform binding */
	static const struct of_device_id adi_axi_adc_of_match[] = {
	{ .compatible = "adi,axi-adc-10.0.a", .data = &adi_axi_adc_10_0_a_info },
	{ /* end of list */ }
	};
	MODULE_DEVICE_TABLE(of, adi_axi_adc_of_match);

	static struct platform_driver adi_axi_adc_driver = {
	.driver = {
	.name = KBUILD_MODNAME,
	.of_match_table = adi_axi_adc_of_match,
	},
	.probe = adi_axi_adc_probe,
	};
	module_platform_driver(adi_axi_adc_driver);

	MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
	MODULE_DESCRIPTION("Analog Devices Generic AXI ADC IP core driver");
	MODULE_LICENSE("GPL v2");