drivers/spi/spi-cs42l43.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 //
 // CS42L43 SPI Controller Driver
 //
 // Copyright (C) 2022-2023 Cirrus Logic, Inc. and
 //                         Cirrus Logic International Semiconductor Ltd.

 #include <linux/acpi.h>
 #include <linux/array_size.h>
 #include <linux/bits.h>
 #include <linux/bitfield.h>
 #include <linux/cleanup.h>
 #include <linux/device.h>
 #include <linux/errno.h>
 #include <linux/gpio/machine.h>
 #include <linux/gpio/property.h>
 #include <linux/mfd/cs42l43.h>
 #include <linux/mfd/cs42l43-regs.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/property.h>
 #include <linux/regmap.h>
 #include <linux/spi/spi.h>
 #include <linux/units.h>

 #define CS42L43_FIFO_SIZE		16
 #define CS42L43_SPI_ROOT_HZ		49152000
 #define CS42L43_SPI_MAX_LENGTH		65532

 enum cs42l43_spi_cmd {
 	CS42L43_WRITE,
 	CS42L43_READ
 };

 struct cs42l43_spi {
 	struct device *dev;
 	struct regmap *regmap;
 	struct spi_controller *ctlr;
 };

 static const unsigned int cs42l43_clock_divs[] = {
 	2, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30
 };

 static struct spi_board_info amp_info_template = {
 	.modalias		= "cs35l56",
 	.max_speed_hz		= 11 * HZ_PER_MHZ,
 	.mode			= SPI_MODE_0,
 };

 static const struct software_node cs42l43_gpiochip_swnode = {
 	.name			= "cs42l43-pinctrl",
 };

 static const struct software_node_ref_args cs42l43_cs_refs[] = {
 	SOFTWARE_NODE_REFERENCE(&cs42l43_gpiochip_swnode, 0, GPIO_ACTIVE_LOW),
 	SOFTWARE_NODE_REFERENCE(&swnode_gpio_undefined),
 };

 static const struct property_entry cs42l43_cs_props[] = {
 	PROPERTY_ENTRY_REF_ARRAY("cs-gpios", cs42l43_cs_refs),
 	{}
 };

 static int cs42l43_spi_tx(struct regmap *regmap, const u8 *buf, unsigned int len)
 {
 	const u8 *end = buf + len;
 	u32 val = 0;
 	int ret;

 	while (buf < end) {
 		const u8 *block = min(buf + CS42L43_FIFO_SIZE, end);

 		while (buf < block) {
 			const u8 *word = min(buf + sizeof(u32), block);
 			int pad = (buf + sizeof(u32)) - word;

 			while (buf < word) {
 				val >>= BITS_PER_BYTE;
 				val |= FIELD_PREP(GENMASK(31, 24), *buf);

 				buf++;
 			}

 			val >>= pad * BITS_PER_BYTE;

 			regmap_write(regmap, CS42L43_TX_DATA, val);
 		}

 		regmap_write(regmap, CS42L43_TRAN_CONFIG8, CS42L43_SPI_TX_DONE_MASK);

 		ret = regmap_read_poll_timeout(regmap, CS42L43_TRAN_STATUS1,
 					       val, (val & CS42L43_SPI_TX_REQUEST_MASK),
 					       1000, 5000);
 		if (ret)
 			return ret;
 	}

 	return 0;
 }

 static int cs42l43_spi_rx(struct regmap *regmap, u8 *buf, unsigned int len)
 {
 	u8 *end = buf + len;
 	u32 val;
 	int ret;

 	while (buf < end) {
 		u8 *block = min(buf + CS42L43_FIFO_SIZE, end);

 		ret = regmap_read_poll_timeout(regmap, CS42L43_TRAN_STATUS1,
 					       val, (val & CS42L43_SPI_RX_REQUEST_MASK),
 					       1000, 5000);
 		if (ret)
 			return ret;

 		while (buf < block) {
 			u8 *word = min(buf + sizeof(u32), block);

 			ret = regmap_read(regmap, CS42L43_RX_DATA, &val);
 			if (ret)
 				return ret;

 			while (buf < word) {
 				*buf = FIELD_GET(GENMASK(7, 0), val);

 				val >>= BITS_PER_BYTE;
 				buf++;
 			}
 		}

 		regmap_write(regmap, CS42L43_TRAN_CONFIG8, CS42L43_SPI_RX_DONE_MASK);
 	}

 	return 0;
 }

 static int cs42l43_transfer_one(struct spi_controller *ctlr, struct spi_device *spi,
 				struct spi_transfer *tfr)
 {
 	struct cs42l43_spi *priv = spi_controller_get_devdata(spi->controller);
 	int i, ret = -EINVAL;

 	for (i = 0; i < ARRAY_SIZE(cs42l43_clock_divs); i++) {
 		if (CS42L43_SPI_ROOT_HZ / cs42l43_clock_divs[i] <= tfr->speed_hz)
 			break;
 	}

 	if (i == ARRAY_SIZE(cs42l43_clock_divs))
 		return -EINVAL;

 	regmap_write(priv->regmap, CS42L43_SPI_CLK_CONFIG1, i);

 	if (tfr->tx_buf) {
 		regmap_write(priv->regmap, CS42L43_TRAN_CONFIG3, CS42L43_WRITE);
 		regmap_write(priv->regmap, CS42L43_TRAN_CONFIG4, tfr->len - 1);
 	} else if (tfr->rx_buf) {
 		regmap_write(priv->regmap, CS42L43_TRAN_CONFIG3, CS42L43_READ);
 		regmap_write(priv->regmap, CS42L43_TRAN_CONFIG5, tfr->len - 1);
 	}

 	regmap_write(priv->regmap, CS42L43_TRAN_CONFIG1, CS42L43_SPI_START_MASK);

 	if (tfr->tx_buf)
 		ret = cs42l43_spi_tx(priv->regmap, (const u8 *)tfr->tx_buf, tfr->len);
 	else if (tfr->rx_buf)
 		ret = cs42l43_spi_rx(priv->regmap, (u8 *)tfr->rx_buf, tfr->len);

 	return ret;
 }

 static void cs42l43_set_cs(struct spi_device *spi, bool is_high)
 {
 	struct cs42l43_spi *priv = spi_controller_get_devdata(spi->controller);

 	regmap_write(priv->regmap, CS42L43_SPI_CONFIG2, !is_high);
 }

 static int cs42l43_prepare_message(struct spi_controller *ctlr, struct spi_message *msg)
 {
 	struct cs42l43_spi *priv = spi_controller_get_devdata(ctlr);
 	struct spi_device *spi = msg->spi;
 	unsigned int spi_config1 = 0;

 	/* select another internal CS, which doesn't exist, so CS 0 is not used */
 	if (spi_get_csgpiod(spi, 0))
 		spi_config1 |= 1 << CS42L43_SPI_SS_SEL_SHIFT;
 	if (spi->mode & SPI_CPOL)
 		spi_config1 |= CS42L43_SPI_CPOL_MASK;
 	if (spi->mode & SPI_CPHA)
 		spi_config1 |= CS42L43_SPI_CPHA_MASK;
 	if (spi->mode & SPI_3WIRE)
 		spi_config1 |= CS42L43_SPI_THREE_WIRE_MASK;

 	regmap_write(priv->regmap, CS42L43_SPI_CONFIG1, spi_config1);

 	return 0;
 }

 static int cs42l43_prepare_transfer_hardware(struct spi_controller *ctlr)
 {
 	struct cs42l43_spi *priv = spi_controller_get_devdata(ctlr);
 	int ret;

 	ret = regmap_write(priv->regmap, CS42L43_BLOCK_EN2, CS42L43_SPI_MSTR_EN_MASK);
 	if (ret)
 		dev_err(priv->dev, "Failed to enable SPI controller: %d\n", ret);

 	return ret;
 }

 static int cs42l43_unprepare_transfer_hardware(struct spi_controller *ctlr)
 {
 	struct cs42l43_spi *priv = spi_controller_get_devdata(ctlr);
 	int ret;

 	ret = regmap_write(priv->regmap, CS42L43_BLOCK_EN2, 0);
 	if (ret)
 		dev_err(priv->dev, "Failed to disable SPI controller: %d\n", ret);

 	return ret;
 }

 static size_t cs42l43_spi_max_length(struct spi_device *spi)
 {
 	return CS42L43_SPI_MAX_LENGTH;
 }

 static struct fwnode_handle *cs42l43_find_xu_node(struct fwnode_handle *fwnode)
 {
 	static const u32 func_smart_amp = 0x1;
 	struct fwnode_handle *child_fwnode, *ext_fwnode;
 	u32 function;
 	int ret;

 	fwnode_for_each_child_node(fwnode, child_fwnode) {
 		acpi_handle handle = ACPI_HANDLE_FWNODE(child_fwnode);

 		ret = acpi_get_local_address(handle, &function);
 		if (ret || function != func_smart_amp)
 			continue;

 		ext_fwnode = fwnode_get_named_child_node(child_fwnode,
 				"mipi-sdca-function-expansion-subproperties");
 		if (!ext_fwnode)
 			continue;

 		fwnode_handle_put(child_fwnode);

 		return ext_fwnode;
 	}

 	return NULL;
 }

 static struct spi_board_info *cs42l43_create_bridge_amp(struct cs42l43_spi *priv,
 							const char * const name,
 							int cs, int spkid)
 {
 	struct property_entry *props = NULL;
 	struct software_node *swnode;
 	struct spi_board_info *info;

 	if (spkid >= 0) {
 		props = devm_kmalloc(priv->dev, sizeof(*props), GFP_KERNEL);
 		if (!props)
 			return NULL;

 		*props = PROPERTY_ENTRY_U32("cirrus,speaker-id", spkid);
 	}

 	swnode = devm_kmalloc(priv->dev, sizeof(*swnode), GFP_KERNEL);
 	if (!swnode)
 		return NULL;

 	*swnode = SOFTWARE_NODE(name, props, NULL);

 	info = devm_kmemdup(priv->dev, &amp_info_template,
 			    sizeof(amp_info_template), GFP_KERNEL);
 	if (!info)
 		return NULL;

 	info->chip_select = cs;
 	info->swnode = swnode;

 	return info;
 }

 static void cs42l43_release_of_node(void *data)
 {
 	fwnode_handle_put(data);
 }

 static void cs42l43_release_sw_node(void *data)
 {
 	software_node_unregister(&cs42l43_gpiochip_swnode);
 }

 static int cs42l43_spi_probe(struct platform_device *pdev)
 {
 	struct cs42l43 *cs42l43 = dev_get_drvdata(pdev->dev.parent);
 	struct cs42l43_spi *priv;
 	struct fwnode_handle *fwnode = dev_fwnode(cs42l43->dev);
 	struct fwnode_handle *xu_fwnode __free(fwnode_handle) = cs42l43_find_xu_node(fwnode);
 	int nsidecars = 0;
 	int ret;

 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;

 	priv->ctlr = devm_spi_alloc_host(&pdev->dev, sizeof(*priv->ctlr));
 	if (!priv->ctlr)
 		return -ENOMEM;

 	spi_controller_set_devdata(priv->ctlr, priv);

 	priv->dev = &pdev->dev;
 	priv->regmap = cs42l43->regmap;

 	priv->ctlr->prepare_message = cs42l43_prepare_message;
 	priv->ctlr->prepare_transfer_hardware = cs42l43_prepare_transfer_hardware;
 	priv->ctlr->unprepare_transfer_hardware = cs42l43_unprepare_transfer_hardware;
 	priv->ctlr->transfer_one = cs42l43_transfer_one;
 	priv->ctlr->set_cs = cs42l43_set_cs;
 	priv->ctlr->max_transfer_size = cs42l43_spi_max_length;
 	priv->ctlr->mode_bits = SPI_3WIRE | SPI_MODE_X_MASK;
 	priv->ctlr->flags = SPI_CONTROLLER_HALF_DUPLEX;
 	priv->ctlr->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16) |
 					 SPI_BPW_MASK(32);
 	priv->ctlr->min_speed_hz = CS42L43_SPI_ROOT_HZ /
 				   cs42l43_clock_divs[ARRAY_SIZE(cs42l43_clock_divs) - 1];
 	priv->ctlr->max_speed_hz = CS42L43_SPI_ROOT_HZ / cs42l43_clock_divs[0];
 	priv->ctlr->use_gpio_descriptors = true;
 	priv->ctlr->auto_runtime_pm = true;

 	ret = devm_pm_runtime_enable(priv->dev);
 	if (ret)
 		return ret;

 	pm_runtime_idle(priv->dev);

 	regmap_write(priv->regmap, CS42L43_TRAN_CONFIG6, CS42L43_FIFO_SIZE - 1);
 	regmap_write(priv->regmap, CS42L43_TRAN_CONFIG7, CS42L43_FIFO_SIZE - 1);

 	// Disable Watchdog timer and enable stall
 	regmap_write(priv->regmap, CS42L43_SPI_CONFIG3, 0);
 	regmap_write(priv->regmap, CS42L43_SPI_CONFIG4, CS42L43_SPI_STALL_ENA_MASK);

 	if (is_of_node(fwnode)) {
 		fwnode = fwnode_get_named_child_node(fwnode, "spi");
 		ret = devm_add_action_or_reset(priv->dev, cs42l43_release_of_node, fwnode);
 		if (ret)
 			return ret;
 	}

 	fwnode_property_read_u32(xu_fwnode, "01fa-sidecar-instances", &nsidecars);

 	if (nsidecars) {
 		ret = software_node_register(&cs42l43_gpiochip_swnode);
 		if (ret)
 			return dev_err_probe(priv->dev, ret,
 					     "Failed to register gpio swnode\n");

 		ret = devm_add_action_or_reset(priv->dev, cs42l43_release_sw_node, NULL);
 		if (ret)
 			return ret;

 		ret = device_create_managed_software_node(&priv->ctlr->dev,
 							  cs42l43_cs_props, NULL);
 		if (ret)
 			return dev_err_probe(priv->dev, ret, "Failed to add swnode\n");
 	} else {
 		device_set_node(&priv->ctlr->dev, fwnode);
 	}

 	ret = devm_spi_register_controller(priv->dev, priv->ctlr);
 	if (ret)
 		return dev_err_probe(priv->dev, ret,
 				     "Failed to register SPI controller\n");

 	if (nsidecars) {
 		struct spi_board_info *ampl_info;
 		struct spi_board_info *ampr_info;
 		int spkid = -EINVAL;

 		fwnode_property_read_u32(xu_fwnode, "01fa-spk-id-val", &spkid);

 		dev_dbg(priv->dev, "Found speaker ID %d\n", spkid);

 		ampl_info = cs42l43_create_bridge_amp(priv, "cs35l56-left", 0, spkid);
 		if (!ampl_info)
 			return -ENOMEM;

 		ampr_info = cs42l43_create_bridge_amp(priv, "cs35l56-right", 1, spkid);
 		if (!ampr_info)
 			return -ENOMEM;

 		if (!spi_new_device(priv->ctlr, ampl_info))
 			return dev_err_probe(priv->dev, -ENODEV,
 					     "Failed to create left amp slave\n");

 		if (!spi_new_device(priv->ctlr, ampr_info))
 			return dev_err_probe(priv->dev, -ENODEV,
 					     "Failed to create right amp slave\n");
 	}

 	return 0;
 }

 static const struct platform_device_id cs42l43_spi_id_table[] = {
 	{ "cs42l43-spi", },
 	{}
 };
 MODULE_DEVICE_TABLE(platform, cs42l43_spi_id_table);

 static struct platform_driver cs42l43_spi_driver = {
 	.driver = {
 		.name	= "cs42l43-spi",
 	},
 	.probe		= cs42l43_spi_probe,
 	.id_table	= cs42l43_spi_id_table,
 };
 module_platform_driver(cs42l43_spi_driver);

 MODULE_IMPORT_NS(GPIO_SWNODE);
 MODULE_DESCRIPTION("CS42L43 SPI Driver");
 MODULE_AUTHOR("Lucas Tanure <tanureal@opensource.cirrus.com>");
 MODULE_AUTHOR("Maciej Strozek <mstrozek@opensource.cirrus.com>");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0
	//
	// CS42L43 SPI Controller Driver
	//
	// Copyright (C) 2022-2023 Cirrus Logic, Inc. and
	// Cirrus Logic International Semiconductor Ltd.

	#include <linux/acpi.h>
	#include <linux/array_size.h>
	#include <linux/bits.h>
	#include <linux/bitfield.h>
	#include <linux/cleanup.h>
	#include <linux/device.h>
	#include <linux/errno.h>
	#include <linux/gpio/machine.h>
	#include <linux/gpio/property.h>
	#include <linux/mfd/cs42l43.h>
	#include <linux/mfd/cs42l43-regs.h>
	#include <linux/mod_devicetable.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/platform_device.h>
	#include <linux/pm_runtime.h>
	#include <linux/property.h>
	#include <linux/regmap.h>
	#include <linux/spi/spi.h>
	#include <linux/units.h>

	#define CS42L43_FIFO_SIZE 16
	#define CS42L43_SPI_ROOT_HZ 49152000
	#define CS42L43_SPI_MAX_LENGTH 65532

	enum cs42l43_spi_cmd {
	CS42L43_WRITE,
	CS42L43_READ
	};

	struct cs42l43_spi {
	struct device *dev;
	struct regmap *regmap;
	struct spi_controller *ctlr;
	};

	static const unsigned int cs42l43_clock_divs[] = {
	2, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30
	};

	static struct spi_board_info amp_info_template = {
	.modalias = "cs35l56",
	.max_speed_hz = 11 * HZ_PER_MHZ,
	.mode = SPI_MODE_0,
	};

	static const struct software_node cs42l43_gpiochip_swnode = {
	.name = "cs42l43-pinctrl",
	};

	static const struct software_node_ref_args cs42l43_cs_refs[] = {
	SOFTWARE_NODE_REFERENCE(&cs42l43_gpiochip_swnode, 0, GPIO_ACTIVE_LOW),
	SOFTWARE_NODE_REFERENCE(&swnode_gpio_undefined),
	};

	static const struct property_entry cs42l43_cs_props[] = {
	PROPERTY_ENTRY_REF_ARRAY("cs-gpios", cs42l43_cs_refs),
	{}
	};

	static int cs42l43_spi_tx(struct regmap regmap, const u8 buf, unsigned int len)
	{
	const u8 *end = buf + len;
	u32 val = 0;
	int ret;

	while (buf < end) {
	const u8 *block = min(buf + CS42L43_FIFO_SIZE, end);

	while (buf < block) {
	const u8 *word = min(buf + sizeof(u32), block);
	int pad = (buf + sizeof(u32)) - word;

	while (buf < word) {
	val >>= BITS_PER_BYTE;
	val \|= FIELD_PREP(GENMASK(31, 24), *buf);

	buf++;
	}

	val >>= pad * BITS_PER_BYTE;

	regmap_write(regmap, CS42L43_TX_DATA, val);
	}

	regmap_write(regmap, CS42L43_TRAN_CONFIG8, CS42L43_SPI_TX_DONE_MASK);

	ret = regmap_read_poll_timeout(regmap, CS42L43_TRAN_STATUS1,
	val, (val & CS42L43_SPI_TX_REQUEST_MASK),
	1000, 5000);
	if (ret)
	return ret;
	}

	return 0;
	}

	static int cs42l43_spi_rx(struct regmap regmap, u8 buf, unsigned int len)
	{
	u8 *end = buf + len;
	u32 val;
	int ret;

	while (buf < end) {
	u8 *block = min(buf + CS42L43_FIFO_SIZE, end);

	ret = regmap_read_poll_timeout(regmap, CS42L43_TRAN_STATUS1,
	val, (val & CS42L43_SPI_RX_REQUEST_MASK),
	1000, 5000);
	if (ret)
	return ret;

	while (buf < block) {
	u8 *word = min(buf + sizeof(u32), block);

	ret = regmap_read(regmap, CS42L43_RX_DATA, &val);
	if (ret)
	return ret;

	while (buf < word) {
	*buf = FIELD_GET(GENMASK(7, 0), val);

	val >>= BITS_PER_BYTE;
	buf++;
	}
	}

	regmap_write(regmap, CS42L43_TRAN_CONFIG8, CS42L43_SPI_RX_DONE_MASK);
	}

	return 0;
	}

	static int cs42l43_transfer_one(struct spi_controller ctlr, struct spi_device spi,
	struct spi_transfer *tfr)
	{
	struct cs42l43_spi *priv = spi_controller_get_devdata(spi->controller);
	int i, ret = -EINVAL;

	for (i = 0; i < ARRAY_SIZE(cs42l43_clock_divs); i++) {
	if (CS42L43_SPI_ROOT_HZ / cs42l43_clock_divs[i] <= tfr->speed_hz)
	break;
	}

	if (i == ARRAY_SIZE(cs42l43_clock_divs))
	return -EINVAL;

	regmap_write(priv->regmap, CS42L43_SPI_CLK_CONFIG1, i);

	if (tfr->tx_buf) {
	regmap_write(priv->regmap, CS42L43_TRAN_CONFIG3, CS42L43_WRITE);
	regmap_write(priv->regmap, CS42L43_TRAN_CONFIG4, tfr->len - 1);
	} else if (tfr->rx_buf) {
	regmap_write(priv->regmap, CS42L43_TRAN_CONFIG3, CS42L43_READ);
	regmap_write(priv->regmap, CS42L43_TRAN_CONFIG5, tfr->len - 1);
	}

	regmap_write(priv->regmap, CS42L43_TRAN_CONFIG1, CS42L43_SPI_START_MASK);

	if (tfr->tx_buf)
	ret = cs42l43_spi_tx(priv->regmap, (const u8 *)tfr->tx_buf, tfr->len);
	else if (tfr->rx_buf)
	ret = cs42l43_spi_rx(priv->regmap, (u8 *)tfr->rx_buf, tfr->len);

	return ret;
	}

	static void cs42l43_set_cs(struct spi_device *spi, bool is_high)
	{
	struct cs42l43_spi *priv = spi_controller_get_devdata(spi->controller);

	regmap_write(priv->regmap, CS42L43_SPI_CONFIG2, !is_high);
	}

	static int cs42l43_prepare_message(struct spi_controller ctlr, struct spi_message msg)
	{
	struct cs42l43_spi *priv = spi_controller_get_devdata(ctlr);
	struct spi_device *spi = msg->spi;
	unsigned int spi_config1 = 0;

	/* select another internal CS, which doesn't exist, so CS 0 is not used */
	if (spi_get_csgpiod(spi, 0))
	spi_config1 \|= 1 << CS42L43_SPI_SS_SEL_SHIFT;
	if (spi->mode & SPI_CPOL)
	spi_config1 \|= CS42L43_SPI_CPOL_MASK;
	if (spi->mode & SPI_CPHA)
	spi_config1 \|= CS42L43_SPI_CPHA_MASK;
	if (spi->mode & SPI_3WIRE)
	spi_config1 \|= CS42L43_SPI_THREE_WIRE_MASK;

	regmap_write(priv->regmap, CS42L43_SPI_CONFIG1, spi_config1);

	return 0;
	}

	static int cs42l43_prepare_transfer_hardware(struct spi_controller *ctlr)
	{
	struct cs42l43_spi *priv = spi_controller_get_devdata(ctlr);
	int ret;

	ret = regmap_write(priv->regmap, CS42L43_BLOCK_EN2, CS42L43_SPI_MSTR_EN_MASK);
	if (ret)
	dev_err(priv->dev, "Failed to enable SPI controller: %d\n", ret);

	return ret;
	}

	static int cs42l43_unprepare_transfer_hardware(struct spi_controller *ctlr)
	{
	struct cs42l43_spi *priv = spi_controller_get_devdata(ctlr);
	int ret;

	ret = regmap_write(priv->regmap, CS42L43_BLOCK_EN2, 0);
	if (ret)
	dev_err(priv->dev, "Failed to disable SPI controller: %d\n", ret);

	return ret;
	}

	static size_t cs42l43_spi_max_length(struct spi_device *spi)
	{
	return CS42L43_SPI_MAX_LENGTH;
	}

	static struct fwnode_handle cs42l43_find_xu_node(struct fwnode_handle fwnode)
	{
	static const u32 func_smart_amp = 0x1;
	struct fwnode_handle child_fwnode, ext_fwnode;
	u32 function;
	int ret;

	fwnode_for_each_child_node(fwnode, child_fwnode) {
	acpi_handle handle = ACPI_HANDLE_FWNODE(child_fwnode);

	ret = acpi_get_local_address(handle, &function);
	if (ret \|\| function != func_smart_amp)
	continue;

	ext_fwnode = fwnode_get_named_child_node(child_fwnode,
	"mipi-sdca-function-expansion-subproperties");
	if (!ext_fwnode)
	continue;

	fwnode_handle_put(child_fwnode);

	return ext_fwnode;
	}

	return NULL;
	}

	static struct spi_board_info cs42l43_create_bridge_amp(struct cs42l43_spi priv,
	const char * const name,
	int cs, int spkid)
	{
	struct property_entry *props = NULL;
	struct software_node *swnode;
	struct spi_board_info *info;

	if (spkid >= 0) {
	props = devm_kmalloc(priv->dev, sizeof(*props), GFP_KERNEL);
	if (!props)
	return NULL;

	*props = PROPERTY_ENTRY_U32("cirrus,speaker-id", spkid);
	}

	swnode = devm_kmalloc(priv->dev, sizeof(*swnode), GFP_KERNEL);
	if (!swnode)
	return NULL;

	*swnode = SOFTWARE_NODE(name, props, NULL);

	info = devm_kmemdup(priv->dev, &amp_info_template,
	sizeof(amp_info_template), GFP_KERNEL);
	if (!info)
	return NULL;

	info->chip_select = cs;
	info->swnode = swnode;

	return info;
	}

	static void cs42l43_release_of_node(void *data)
	{
	fwnode_handle_put(data);
	}

	static void cs42l43_release_sw_node(void *data)
	{
	software_node_unregister(&cs42l43_gpiochip_swnode);
	}

	static int cs42l43_spi_probe(struct platform_device *pdev)
	{
	struct cs42l43 *cs42l43 = dev_get_drvdata(pdev->dev.parent);
	struct cs42l43_spi *priv;
	struct fwnode_handle *fwnode = dev_fwnode(cs42l43->dev);
	struct fwnode_handle *xu_fwnode __free(fwnode_handle) = cs42l43_find_xu_node(fwnode);
	int nsidecars = 0;
	int ret;

	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
	return -ENOMEM;

	priv->ctlr = devm_spi_alloc_host(&pdev->dev, sizeof(*priv->ctlr));
	if (!priv->ctlr)
	return -ENOMEM;

	spi_controller_set_devdata(priv->ctlr, priv);

	priv->dev = &pdev->dev;
	priv->regmap = cs42l43->regmap;

	priv->ctlr->prepare_message = cs42l43_prepare_message;
	priv->ctlr->prepare_transfer_hardware = cs42l43_prepare_transfer_hardware;
	priv->ctlr->unprepare_transfer_hardware = cs42l43_unprepare_transfer_hardware;
	priv->ctlr->transfer_one = cs42l43_transfer_one;
	priv->ctlr->set_cs = cs42l43_set_cs;
	priv->ctlr->max_transfer_size = cs42l43_spi_max_length;
	priv->ctlr->mode_bits = SPI_3WIRE \| SPI_MODE_X_MASK;
	priv->ctlr->flags = SPI_CONTROLLER_HALF_DUPLEX;
	priv->ctlr->bits_per_word_mask = SPI_BPW_MASK(8) \| SPI_BPW_MASK(16) \|
	SPI_BPW_MASK(32);
	priv->ctlr->min_speed_hz = CS42L43_SPI_ROOT_HZ /
	cs42l43_clock_divs[ARRAY_SIZE(cs42l43_clock_divs) - 1];
	priv->ctlr->max_speed_hz = CS42L43_SPI_ROOT_HZ / cs42l43_clock_divs[0];
	priv->ctlr->use_gpio_descriptors = true;
	priv->ctlr->auto_runtime_pm = true;

	ret = devm_pm_runtime_enable(priv->dev);
	if (ret)
	return ret;

	pm_runtime_idle(priv->dev);

	regmap_write(priv->regmap, CS42L43_TRAN_CONFIG6, CS42L43_FIFO_SIZE - 1);
	regmap_write(priv->regmap, CS42L43_TRAN_CONFIG7, CS42L43_FIFO_SIZE - 1);

	// Disable Watchdog timer and enable stall
	regmap_write(priv->regmap, CS42L43_SPI_CONFIG3, 0);
	regmap_write(priv->regmap, CS42L43_SPI_CONFIG4, CS42L43_SPI_STALL_ENA_MASK);

	if (is_of_node(fwnode)) {
	fwnode = fwnode_get_named_child_node(fwnode, "spi");
	ret = devm_add_action_or_reset(priv->dev, cs42l43_release_of_node, fwnode);
	if (ret)
	return ret;
	}

	fwnode_property_read_u32(xu_fwnode, "01fa-sidecar-instances", &nsidecars);

	if (nsidecars) {
	ret = software_node_register(&cs42l43_gpiochip_swnode);
	if (ret)
	return dev_err_probe(priv->dev, ret,
	"Failed to register gpio swnode\n");

	ret = devm_add_action_or_reset(priv->dev, cs42l43_release_sw_node, NULL);
	if (ret)
	return ret;

	ret = device_create_managed_software_node(&priv->ctlr->dev,
	cs42l43_cs_props, NULL);
	if (ret)
	return dev_err_probe(priv->dev, ret, "Failed to add swnode\n");
	} else {
	device_set_node(&priv->ctlr->dev, fwnode);
	}

	ret = devm_spi_register_controller(priv->dev, priv->ctlr);
	if (ret)
	return dev_err_probe(priv->dev, ret,
	"Failed to register SPI controller\n");

	if (nsidecars) {
	struct spi_board_info *ampl_info;
	struct spi_board_info *ampr_info;
	int spkid = -EINVAL;

	fwnode_property_read_u32(xu_fwnode, "01fa-spk-id-val", &spkid);

	dev_dbg(priv->dev, "Found speaker ID %d\n", spkid);

	ampl_info = cs42l43_create_bridge_amp(priv, "cs35l56-left", 0, spkid);
	if (!ampl_info)
	return -ENOMEM;

	ampr_info = cs42l43_create_bridge_amp(priv, "cs35l56-right", 1, spkid);
	if (!ampr_info)
	return -ENOMEM;

	if (!spi_new_device(priv->ctlr, ampl_info))
	return dev_err_probe(priv->dev, -ENODEV,
	"Failed to create left amp slave\n");

	if (!spi_new_device(priv->ctlr, ampr_info))
	return dev_err_probe(priv->dev, -ENODEV,
	"Failed to create right amp slave\n");
	}

	return 0;
	}

	static const struct platform_device_id cs42l43_spi_id_table[] = {
	{ "cs42l43-spi", },
	{}
	};
	MODULE_DEVICE_TABLE(platform, cs42l43_spi_id_table);

	static struct platform_driver cs42l43_spi_driver = {
	.driver = {
	.name = "cs42l43-spi",
	},
	.probe = cs42l43_spi_probe,
	.id_table = cs42l43_spi_id_table,
	};
	module_platform_driver(cs42l43_spi_driver);

	MODULE_IMPORT_NS(GPIO_SWNODE);
	MODULE_DESCRIPTION("CS42L43 SPI Driver");
	MODULE_AUTHOR("Lucas Tanure <tanureal@opensource.cirrus.com>");
	MODULE_AUTHOR("Maciej Strozek <mstrozek@opensource.cirrus.com>");
	MODULE_LICENSE("GPL");