drivers/spi/spi-uclass.c - platform/external/u-boot - Gitiles

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright (c) 2014 Google, Inc
  */

 #define LOG_CATEGORY UCLASS_SPI

 #include <common.h>
 #include <dm.h>
 #include <errno.h>
 #include <log.h>
 #include <malloc.h>
 #include <spi.h>
 #include <dm/device_compat.h>
 #include <asm/global_data.h>
 #include <dm/device-internal.h>
 #include <dm/uclass-internal.h>
 #include <dm/lists.h>
 #include <dm/util.h>

 DECLARE_GLOBAL_DATA_PTR;

 #define SPI_DEFAULT_SPEED_HZ 100000

 static int spi_set_speed_mode(struct udevice *bus, int speed, int mode)
 {
 	struct dm_spi_ops *ops;
 	int ret;

 	ops = spi_get_ops(bus);
 	if (ops->set_speed)
 		ret = ops->set_speed(bus, speed);
 	else
 		ret = -EINVAL;
 	if (ret) {
 		dev_err(bus, "Cannot set speed (err=%d)\n", ret);
 		return ret;
 	}

 	if (ops->set_mode)
 		ret = ops->set_mode(bus, mode);
 	else
 		ret = -EINVAL;
 	if (ret) {
 		dev_err(bus, "Cannot set mode (err=%d)\n", ret);
 		return ret;
 	}

 	return 0;
 }

 int dm_spi_claim_bus(struct udevice *dev)
 {
 	struct udevice *bus = dev->parent;
 	struct dm_spi_ops *ops = spi_get_ops(bus);
 	struct dm_spi_bus *spi = dev_get_uclass_priv(bus);
 	struct spi_slave *slave = dev_get_parent_priv(dev);
 	uint speed, mode;

 	speed = slave->max_hz;
 	mode = slave->mode;

 	if (spi->max_hz) {
 		if (speed)
 			speed = min(speed, spi->max_hz);
 		else
 			speed = spi->max_hz;
 	}
 	if (!speed)
 		speed = SPI_DEFAULT_SPEED_HZ;

 	if (speed != spi->speed || mode != spi->mode) {
 		int ret = spi_set_speed_mode(bus, speed, slave->mode);

 		if (ret)
 			return log_ret(ret);

 		spi->speed = speed;
 		spi->mode = mode;
 	}

 	return log_ret(ops->claim_bus ? ops->claim_bus(dev) : 0);
 }

 void dm_spi_release_bus(struct udevice *dev)
 {
 	struct udevice *bus = dev->parent;
 	struct dm_spi_ops *ops = spi_get_ops(bus);

 	if (ops->release_bus)
 		ops->release_bus(dev);
 }

 int dm_spi_xfer(struct udevice *dev, unsigned int bitlen,
 		const void *dout, void *din, unsigned long flags)
 {
 	struct udevice *bus = dev->parent;
 	struct dm_spi_ops *ops = spi_get_ops(bus);

 	if (bus->uclass->uc_drv->id != UCLASS_SPI)
 		return -EOPNOTSUPP;
 	if (!ops->xfer)
 		return -ENOSYS;

 	return ops->xfer(dev, bitlen, dout, din, flags);
 }

 int dm_spi_get_mmap(struct udevice *dev, ulong *map_basep, uint *map_sizep,
 		    uint *offsetp)
 {
 	struct udevice *bus = dev->parent;
 	struct dm_spi_ops *ops = spi_get_ops(bus);

 	if (bus->uclass->uc_drv->id != UCLASS_SPI)
 		return -EOPNOTSUPP;
 	if (!ops->get_mmap)
 		return -ENOSYS;

 	return ops->get_mmap(dev, map_basep, map_sizep, offsetp);
 }

 int spi_claim_bus(struct spi_slave *slave)
 {
 	return log_ret(dm_spi_claim_bus(slave->dev));
 }

 void spi_release_bus(struct spi_slave *slave)
 {
 	dm_spi_release_bus(slave->dev);
 }

 int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
 	     const void *dout, void *din, unsigned long flags)
 {
 	return dm_spi_xfer(slave->dev, bitlen, dout, din, flags);
 }

 int spi_write_then_read(struct spi_slave *slave, const u8 *opcode,
 			size_t n_opcode, const u8 *txbuf, u8 *rxbuf,
 			size_t n_buf)
 {
 	unsigned long flags = SPI_XFER_BEGIN;
 	int ret;

 	if (n_buf == 0)
 		flags |= SPI_XFER_END;

 	ret = spi_xfer(slave, n_opcode * 8, opcode, NULL, flags);
 	if (ret) {
 		dev_dbg(slave->dev,
 			"spi: failed to send command (%zu bytes): %d\n",
 			n_opcode, ret);
 	} else if (n_buf != 0) {
 		ret = spi_xfer(slave, n_buf * 8, txbuf, rxbuf, SPI_XFER_END);
 		if (ret)
 			dev_dbg(slave->dev,
 				"spi: failed to transfer %zu bytes of data: %d\n",
 				n_buf, ret);
 	}

 	return ret;
 }

 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
 static int spi_child_post_bind(struct udevice *dev)
 {
 	struct dm_spi_slave_plat *plat = dev_get_parent_plat(dev);

 	if (!dev_has_ofnode(dev))
 		return 0;

 	return spi_slave_of_to_plat(dev, plat);
 }
 #endif

 static int spi_post_probe(struct udevice *bus)
 {
 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
 	struct dm_spi_bus *spi = dev_get_uclass_priv(bus);

 	spi->max_hz = dev_read_u32_default(bus, "spi-max-frequency", 0);
 #endif
 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
 	struct dm_spi_ops *ops = spi_get_ops(bus);
 	static int reloc_done;

 	if (!reloc_done) {
 		if (ops->claim_bus)
 			ops->claim_bus += gd->reloc_off;
 		if (ops->release_bus)
 			ops->release_bus += gd->reloc_off;
 		if (ops->set_wordlen)
 			ops->set_wordlen += gd->reloc_off;
 		if (ops->xfer)
 			ops->xfer += gd->reloc_off;
 		if (ops->set_speed)
 			ops->set_speed += gd->reloc_off;
 		if (ops->set_mode)
 			ops->set_mode += gd->reloc_off;
 		if (ops->cs_info)
 			ops->cs_info += gd->reloc_off;
 		reloc_done++;
 	}
 #endif

 	return 0;
 }

 static int spi_child_pre_probe(struct udevice *dev)
 {
 	struct dm_spi_slave_plat *plat = dev_get_parent_plat(dev);
 	struct spi_slave *slave = dev_get_parent_priv(dev);

 	/*
 	 * This is needed because we pass struct spi_slave around the place
 	 * instead slave->dev (a struct udevice). So we have to have some
 	 * way to access the slave udevice given struct spi_slave. Once we
 	 * change the SPI API to use udevice instead of spi_slave, we can
 	 * drop this.
 	 */
 	slave->dev = dev;

 	slave->max_hz = plat->max_hz;
 	slave->mode = plat->mode;
 	slave->wordlen = SPI_DEFAULT_WORDLEN;

 	return 0;
 }

 int spi_chip_select(struct udevice *dev)
 {
 	struct dm_spi_slave_plat *plat = dev_get_parent_plat(dev);

 	return plat ? plat->cs : -ENOENT;
 }

 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp)
 {
 	struct dm_spi_ops *ops;
 	struct spi_cs_info info;
 	struct udevice *dev;
 	int ret;

 	/*
 	 * Ask the driver. For the moment we don't have CS info.
 	 * When we do we could provide the driver with a helper function
 	 * to figure out what chip selects are valid, or just handle the
 	 * request.
 	 */
 	ops = spi_get_ops(bus);
 	if (ops->cs_info) {
 		ret = ops->cs_info(bus, cs, &info);
 	} else {
 		/*
 		 * We could assume there is at least one valid chip select.
 		 * The driver didn't care enough to tell us.
 		 */
 		ret = 0;
 	}

 	if (ret) {
 		dev_err(bus, "Invalid cs %d (err=%d)\n", cs, ret);
 		return ret;
 	}

 	for (device_find_first_child(bus, &dev); dev;
 	     device_find_next_child(&dev)) {
 		struct dm_spi_slave_plat *plat;

 		plat = dev_get_parent_plat(dev);
 		dev_dbg(bus, "%s: plat=%p, cs=%d\n", __func__, plat, plat->cs);
 		if (plat->cs == cs) {
 			*devp = dev;
 			return 0;
 		}
 	}

 	return -ENODEV;
 }

 int spi_cs_is_valid(unsigned int busnum, unsigned int cs)
 {
 	struct spi_cs_info info;
 	struct udevice *bus;
 	int ret;

 	ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, &bus);
 	if (ret) {
 		log_debug("%s: No bus %d\n", __func__, busnum);
 		return ret;
 	}

 	return spi_cs_info(bus, cs, &info);
 }

 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info)
 {
 	struct spi_cs_info local_info;
 	int ret;

 	if (!info)
 		info = &local_info;

 	/* If there is a device attached, return it */
 	info->dev = NULL;
 	ret = spi_find_chip_select(bus, cs, &info->dev);
 	return ret == -ENODEV ? 0 : ret;
 }

 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,
 			struct udevice **devp)
 {
 	struct udevice *bus, *dev;
 	int ret;

 	ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, &bus);
 	if (ret) {
 		log_debug("%s: No bus %d\n", __func__, busnum);
 		return ret;
 	}
 	ret = spi_find_chip_select(bus, cs, &dev);
 	if (ret) {
 		dev_dbg(bus, "%s: No cs %d\n", __func__, cs);
 		return ret;
 	}
 	*busp = bus;
 	*devp = dev;

 	return ret;
 }

 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
 		       const char *drv_name, const char *dev_name,
 		       struct udevice **busp, struct spi_slave **devp)
 {
 	struct udevice *bus, *dev;
 	struct dm_spi_slave_plat *plat;
 	struct dm_spi_bus *bus_data;
 	struct spi_slave *slave;
 	bool created = false;
 	int ret;

 #if CONFIG_IS_ENABLED(OF_PLATDATA)
 	ret = uclass_first_device_err(UCLASS_SPI, &bus);
 #else
 	ret = uclass_get_device_by_seq(UCLASS_SPI, busnum, &bus);
 #endif
 	if (ret) {
 		log_err("Invalid bus %d (err=%d)\n", busnum, ret);
 		return ret;
 	}
 	ret = spi_find_chip_select(bus, cs, &dev);

 	/*
 	 * If there is no such device, create one automatically. This means
 	 * that we don't need a device tree node or platform data for the
 	 * SPI flash chip - we will bind to the correct driver.
 	 */
 	if (ret == -ENODEV && drv_name) {
 		dev_dbg(bus, "%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n",
 			__func__, dev_name, busnum, cs, drv_name);
 		ret = device_bind_driver(bus, drv_name, dev_name, &dev);
 		if (ret) {
 			dev_dbg(bus, "%s: Unable to bind driver (ret=%d)\n",
 				__func__, ret);
 			return ret;
 		}
 		plat = dev_get_parent_plat(dev);
 		plat->cs = cs;
 		if (speed) {
 			plat->max_hz = speed;
 		} else {
 			dev_warn(bus,
 				 "Warning: SPI speed fallback to %u kHz\n",
 				 SPI_DEFAULT_SPEED_HZ / 1000);
 			plat->max_hz = SPI_DEFAULT_SPEED_HZ;
 		}
 		plat->mode = mode;
 		created = true;
 	} else if (ret) {
 		dev_err(bus, "Invalid chip select %d:%d (err=%d)\n", busnum, cs, ret);
 		return ret;
 	}

 	if (!device_active(dev)) {
 		struct spi_slave *slave;

 		ret = device_probe(dev);
 		if (ret)
 			goto err;
 		slave = dev_get_parent_priv(dev);
 		slave->dev = dev;
 	}

 	slave = dev_get_parent_priv(dev);
 	bus_data = dev_get_uclass_priv(bus);

 	/*
 	 * In case the operation speed is not yet established by
 	 * dm_spi_claim_bus() ensure the bus is configured properly.
 	 */
 	if (!bus_data->speed) {
 		ret = spi_claim_bus(slave);
 		if (ret)
 			goto err;
 	}

 	*busp = bus;
 	*devp = slave;
 	log_debug("%s: bus=%p, slave=%p\n", __func__, bus, *devp);

 	return 0;

 err:
 	log_debug("%s: Error path, created=%d, device '%s'\n", __func__,
 		  created, dev->name);
 	if (created) {
 		device_remove(dev, DM_REMOVE_NORMAL);
 		device_unbind(dev);
 	}

 	return ret;
 }

 /* Compatibility function - to be removed */
 struct spi_slave *spi_setup_slave(unsigned int busnum, unsigned int cs,
 				  unsigned int speed, unsigned int mode)
 {
 	struct spi_slave *slave;
 	struct udevice *dev;
 	int ret;

 	ret = spi_get_bus_and_cs(busnum, cs, speed, mode, NULL, 0, &dev,
 				 &slave);
 	if (ret)
 		return NULL;

 	return slave;
 }

 void spi_free_slave(struct spi_slave *slave)
 {
 	device_remove(slave->dev, DM_REMOVE_NORMAL);
 }

 int spi_slave_of_to_plat(struct udevice *dev, struct dm_spi_slave_plat *plat)
 {
 	int mode = 0;
 	int value;

 	plat->cs = dev_read_u32_default(dev, "reg", -1);
 	plat->max_hz = dev_read_u32_default(dev, "spi-max-frequency",
 					    SPI_DEFAULT_SPEED_HZ);
 	if (dev_read_bool(dev, "spi-cpol"))
 		mode |= SPI_CPOL;
 	if (dev_read_bool(dev, "spi-cpha"))
 		mode |= SPI_CPHA;
 	if (dev_read_bool(dev, "spi-cs-high"))
 		mode |= SPI_CS_HIGH;
 	if (dev_read_bool(dev, "spi-3wire"))
 		mode |= SPI_3WIRE;
 	if (dev_read_bool(dev, "spi-half-duplex"))
 		mode |= SPI_PREAMBLE;

 	/* Device DUAL/QUAD mode */
 	value = dev_read_u32_default(dev, "spi-tx-bus-width", 1);
 	switch (value) {
 	case 1:
 		break;
 	case 2:
 		mode |= SPI_TX_DUAL;
 		break;
 	case 4:
 		mode |= SPI_TX_QUAD;
 		break;
 	case 8:
 		mode |= SPI_TX_OCTAL;
 		break;
 	default:
 		warn_non_spl("spi-tx-bus-width %d not supported\n", value);
 		break;
 	}

 	value = dev_read_u32_default(dev, "spi-rx-bus-width", 1);
 	switch (value) {
 	case 1:
 		break;
 	case 2:
 		mode |= SPI_RX_DUAL;
 		break;
 	case 4:
 		mode |= SPI_RX_QUAD;
 		break;
 	case 8:
 		mode |= SPI_RX_OCTAL;
 		break;
 	default:
 		warn_non_spl("spi-rx-bus-width %d not supported\n", value);
 		break;
 	}

 	plat->mode = mode;

 	return 0;
 }

 UCLASS_DRIVER(spi) = {
 	.id		= UCLASS_SPI,
 	.name		= "spi",
 	.flags		= DM_UC_FLAG_SEQ_ALIAS,
 #if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
 	.post_bind	= dm_scan_fdt_dev,
 #endif
 	.post_probe	= spi_post_probe,
 	.child_pre_probe = spi_child_pre_probe,
 	.per_device_auto	= sizeof(struct dm_spi_bus),
 	.per_child_auto	= sizeof(struct spi_slave),
 	.per_child_plat_auto	= sizeof(struct dm_spi_slave_plat),
 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
 	.child_post_bind = spi_child_post_bind,
 #endif
 };

 UCLASS_DRIVER(spi_generic) = {
 	.id		= UCLASS_SPI_GENERIC,
 	.name		= "spi_generic",
 };

 U_BOOT_DRIVER(spi_generic_drv) = {
 	.name		= "spi_generic_drv",
 	.id		= UCLASS_SPI_GENERIC,
 };
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Copyright (c) 2014 Google, Inc
	*/

	#define LOG_CATEGORY UCLASS_SPI

	#include <common.h>
	#include <dm.h>
	#include <errno.h>
	#include <log.h>
	#include <malloc.h>
	#include <spi.h>
	#include <dm/device_compat.h>
	#include <asm/global_data.h>
	#include <dm/device-internal.h>
	#include <dm/uclass-internal.h>
	#include <dm/lists.h>
	#include <dm/util.h>

	DECLARE_GLOBAL_DATA_PTR;

	#define SPI_DEFAULT_SPEED_HZ 100000

	static int spi_set_speed_mode(struct udevice *bus, int speed, int mode)
	{
	struct dm_spi_ops *ops;
	int ret;

	ops = spi_get_ops(bus);
	if (ops->set_speed)
	ret = ops->set_speed(bus, speed);
	else
	ret = -EINVAL;
	if (ret) {
	dev_err(bus, "Cannot set speed (err=%d)\n", ret);
	return ret;
	}

	if (ops->set_mode)
	ret = ops->set_mode(bus, mode);
	else
	ret = -EINVAL;
	if (ret) {
	dev_err(bus, "Cannot set mode (err=%d)\n", ret);
	return ret;
	}

	return 0;
	}

	int dm_spi_claim_bus(struct udevice *dev)
	{
	struct udevice *bus = dev->parent;
	struct dm_spi_ops *ops = spi_get_ops(bus);
	struct dm_spi_bus *spi = dev_get_uclass_priv(bus);
	struct spi_slave *slave = dev_get_parent_priv(dev);
	uint speed, mode;

	speed = slave->max_hz;
	mode = slave->mode;

	if (spi->max_hz) {
	if (speed)
	speed = min(speed, spi->max_hz);
	else
	speed = spi->max_hz;
	}
	if (!speed)
	speed = SPI_DEFAULT_SPEED_HZ;

	if (speed != spi->speed \|\| mode != spi->mode) {
	int ret = spi_set_speed_mode(bus, speed, slave->mode);

	if (ret)
	return log_ret(ret);

	spi->speed = speed;
	spi->mode = mode;
	}

	return log_ret(ops->claim_bus ? ops->claim_bus(dev) : 0);
	}

	void dm_spi_release_bus(struct udevice *dev)
	{
	struct udevice *bus = dev->parent;
	struct dm_spi_ops *ops = spi_get_ops(bus);

	if (ops->release_bus)
	ops->release_bus(dev);
	}

	int dm_spi_xfer(struct udevice *dev, unsigned int bitlen,
	const void dout, void din, unsigned long flags)
	{
	struct udevice *bus = dev->parent;
	struct dm_spi_ops *ops = spi_get_ops(bus);

	if (bus->uclass->uc_drv->id != UCLASS_SPI)
	return -EOPNOTSUPP;
	if (!ops->xfer)
	return -ENOSYS;

	return ops->xfer(dev, bitlen, dout, din, flags);
	}

	int dm_spi_get_mmap(struct udevice dev, ulong map_basep, uint *map_sizep,
	uint *offsetp)
	{
	struct udevice *bus = dev->parent;
	struct dm_spi_ops *ops = spi_get_ops(bus);

	if (bus->uclass->uc_drv->id != UCLASS_SPI)
	return -EOPNOTSUPP;
	if (!ops->get_mmap)
	return -ENOSYS;

	return ops->get_mmap(dev, map_basep, map_sizep, offsetp);
	}

	int spi_claim_bus(struct spi_slave *slave)
	{
	return log_ret(dm_spi_claim_bus(slave->dev));
	}

	void spi_release_bus(struct spi_slave *slave)
	{
	dm_spi_release_bus(slave->dev);
	}

	int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
	const void dout, void din, unsigned long flags)
	{
	return dm_spi_xfer(slave->dev, bitlen, dout, din, flags);
	}

	int spi_write_then_read(struct spi_slave slave, const u8 opcode,
	size_t n_opcode, const u8 txbuf, u8 rxbuf,
	size_t n_buf)
	{
	unsigned long flags = SPI_XFER_BEGIN;
	int ret;

	if (n_buf == 0)
	flags \|= SPI_XFER_END;

	ret = spi_xfer(slave, n_opcode * 8, opcode, NULL, flags);
	if (ret) {
	dev_dbg(slave->dev,
	"spi: failed to send command (%zu bytes): %d\n",
	n_opcode, ret);
	} else if (n_buf != 0) {
	ret = spi_xfer(slave, n_buf * 8, txbuf, rxbuf, SPI_XFER_END);
	if (ret)
	dev_dbg(slave->dev,
	"spi: failed to transfer %zu bytes of data: %d\n",
	n_buf, ret);
	}

	return ret;
	}

	#if !CONFIG_IS_ENABLED(OF_PLATDATA)
	static int spi_child_post_bind(struct udevice *dev)
	{
	struct dm_spi_slave_plat *plat = dev_get_parent_plat(dev);

	if (!dev_has_ofnode(dev))
	return 0;

	return spi_slave_of_to_plat(dev, plat);
	}
	#endif

	static int spi_post_probe(struct udevice *bus)
	{
	#if !CONFIG_IS_ENABLED(OF_PLATDATA)
	struct dm_spi_bus *spi = dev_get_uclass_priv(bus);

	spi->max_hz = dev_read_u32_default(bus, "spi-max-frequency", 0);
	#endif
	#if defined(CONFIG_NEEDS_MANUAL_RELOC)
	struct dm_spi_ops *ops = spi_get_ops(bus);
	static int reloc_done;

	if (!reloc_done) {
	if (ops->claim_bus)
	ops->claim_bus += gd->reloc_off;
	if (ops->release_bus)
	ops->release_bus += gd->reloc_off;
	if (ops->set_wordlen)
	ops->set_wordlen += gd->reloc_off;
	if (ops->xfer)
	ops->xfer += gd->reloc_off;
	if (ops->set_speed)
	ops->set_speed += gd->reloc_off;
	if (ops->set_mode)
	ops->set_mode += gd->reloc_off;
	if (ops->cs_info)
	ops->cs_info += gd->reloc_off;
	reloc_done++;
	}
	#endif

	return 0;
	}

	static int spi_child_pre_probe(struct udevice *dev)
	{
	struct dm_spi_slave_plat *plat = dev_get_parent_plat(dev);
	struct spi_slave *slave = dev_get_parent_priv(dev);

	/*
	* This is needed because we pass struct spi_slave around the place
	* instead slave->dev (a struct udevice). So we have to have some
	* way to access the slave udevice given struct spi_slave. Once we
	* change the SPI API to use udevice instead of spi_slave, we can
	* drop this.
	*/
	slave->dev = dev;

	slave->max_hz = plat->max_hz;
	slave->mode = plat->mode;
	slave->wordlen = SPI_DEFAULT_WORDLEN;

	return 0;
	}

	int spi_chip_select(struct udevice *dev)
	{
	struct dm_spi_slave_plat *plat = dev_get_parent_plat(dev);

	return plat ? plat->cs : -ENOENT;
	}

	int spi_find_chip_select(struct udevice bus, int cs, struct udevice *devp)
	{
	struct dm_spi_ops *ops;
	struct spi_cs_info info;
	struct udevice *dev;
	int ret;

	/*
	* Ask the driver. For the moment we don't have CS info.
	* When we do we could provide the driver with a helper function
	* to figure out what chip selects are valid, or just handle the
	* request.
	*/
	ops = spi_get_ops(bus);
	if (ops->cs_info) {
	ret = ops->cs_info(bus, cs, &info);
	} else {
	/*
	* We could assume there is at least one valid chip select.
	* The driver didn't care enough to tell us.
	*/
	ret = 0;
	}

	if (ret) {
	dev_err(bus, "Invalid cs %d (err=%d)\n", cs, ret);
	return ret;
	}

	for (device_find_first_child(bus, &dev); dev;
	device_find_next_child(&dev)) {
	struct dm_spi_slave_plat *plat;

	plat = dev_get_parent_plat(dev);
	dev_dbg(bus, "%s: plat=%p, cs=%d\n", __func__, plat, plat->cs);
	if (plat->cs == cs) {
	*devp = dev;
	return 0;
	}
	}

	return -ENODEV;
	}

	int spi_cs_is_valid(unsigned int busnum, unsigned int cs)
	{
	struct spi_cs_info info;
	struct udevice *bus;
	int ret;

	ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, &bus);
	if (ret) {
	log_debug("%s: No bus %d\n", __func__, busnum);
	return ret;
	}

	return spi_cs_info(bus, cs, &info);
	}

	int spi_cs_info(struct udevice bus, uint cs, struct spi_cs_info info)
	{
	struct spi_cs_info local_info;
	int ret;

	if (!info)
	info = &local_info;

	/* If there is a device attached, return it */
	info->dev = NULL;
	ret = spi_find_chip_select(bus, cs, &info->dev);
	return ret == -ENODEV ? 0 : ret;
	}

	int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,
	struct udevice **devp)
	{
	struct udevice bus, dev;
	int ret;

	ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, &bus);
	if (ret) {
	log_debug("%s: No bus %d\n", __func__, busnum);
	return ret;
	}
	ret = spi_find_chip_select(bus, cs, &dev);
	if (ret) {
	dev_dbg(bus, "%s: No cs %d\n", __func__, cs);
	return ret;
	}
	*busp = bus;
	*devp = dev;

	return ret;
	}

	int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
	const char drv_name, const char dev_name,
	struct udevice busp, struct spi_slave devp)
	{
	struct udevice bus, dev;
	struct dm_spi_slave_plat *plat;
	struct dm_spi_bus *bus_data;
	struct spi_slave *slave;
	bool created = false;
	int ret;

	#if CONFIG_IS_ENABLED(OF_PLATDATA)
	ret = uclass_first_device_err(UCLASS_SPI, &bus);
	#else
	ret = uclass_get_device_by_seq(UCLASS_SPI, busnum, &bus);
	#endif
	if (ret) {
	log_err("Invalid bus %d (err=%d)\n", busnum, ret);
	return ret;
	}
	ret = spi_find_chip_select(bus, cs, &dev);

	/*
	* If there is no such device, create one automatically. This means
	* that we don't need a device tree node or platform data for the
	* SPI flash chip - we will bind to the correct driver.
	*/
	if (ret == -ENODEV && drv_name) {
	dev_dbg(bus, "%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n",
	__func__, dev_name, busnum, cs, drv_name);
	ret = device_bind_driver(bus, drv_name, dev_name, &dev);
	if (ret) {
	dev_dbg(bus, "%s: Unable to bind driver (ret=%d)\n",
	__func__, ret);
	return ret;
	}
	plat = dev_get_parent_plat(dev);
	plat->cs = cs;
	if (speed) {
	plat->max_hz = speed;
	} else {
	dev_warn(bus,
	"Warning: SPI speed fallback to %u kHz\n",
	SPI_DEFAULT_SPEED_HZ / 1000);
	plat->max_hz = SPI_DEFAULT_SPEED_HZ;
	}
	plat->mode = mode;
	created = true;
	} else if (ret) {
	dev_err(bus, "Invalid chip select %d:%d (err=%d)\n", busnum, cs, ret);
	return ret;
	}

	if (!device_active(dev)) {
	struct spi_slave *slave;

	ret = device_probe(dev);
	if (ret)
	goto err;
	slave = dev_get_parent_priv(dev);
	slave->dev = dev;
	}

	slave = dev_get_parent_priv(dev);
	bus_data = dev_get_uclass_priv(bus);

	/*
	* In case the operation speed is not yet established by
	* dm_spi_claim_bus() ensure the bus is configured properly.
	*/
	if (!bus_data->speed) {
	ret = spi_claim_bus(slave);
	if (ret)
	goto err;
	}

	*busp = bus;
	*devp = slave;
	log_debug("%s: bus=%p, slave=%p\n", __func__, bus, *devp);

	return 0;

	err:
	log_debug("%s: Error path, created=%d, device '%s'\n", __func__,
	created, dev->name);
	if (created) {
	device_remove(dev, DM_REMOVE_NORMAL);
	device_unbind(dev);
	}

	return ret;
	}

	/* Compatibility function - to be removed */
	struct spi_slave *spi_setup_slave(unsigned int busnum, unsigned int cs,
	unsigned int speed, unsigned int mode)
	{
	struct spi_slave *slave;
	struct udevice *dev;
	int ret;

	ret = spi_get_bus_and_cs(busnum, cs, speed, mode, NULL, 0, &dev,
	&slave);
	if (ret)
	return NULL;

	return slave;
	}

	void spi_free_slave(struct spi_slave *slave)
	{
	device_remove(slave->dev, DM_REMOVE_NORMAL);
	}

	int spi_slave_of_to_plat(struct udevice dev, struct dm_spi_slave_plat plat)
	{
	int mode = 0;
	int value;

	plat->cs = dev_read_u32_default(dev, "reg", -1);
	plat->max_hz = dev_read_u32_default(dev, "spi-max-frequency",
	SPI_DEFAULT_SPEED_HZ);
	if (dev_read_bool(dev, "spi-cpol"))
	mode \|= SPI_CPOL;
	if (dev_read_bool(dev, "spi-cpha"))
	mode \|= SPI_CPHA;
	if (dev_read_bool(dev, "spi-cs-high"))
	mode \|= SPI_CS_HIGH;
	if (dev_read_bool(dev, "spi-3wire"))
	mode \|= SPI_3WIRE;
	if (dev_read_bool(dev, "spi-half-duplex"))
	mode \|= SPI_PREAMBLE;

	/* Device DUAL/QUAD mode */
	value = dev_read_u32_default(dev, "spi-tx-bus-width", 1);
	switch (value) {
	case 1:
	break;
	case 2:
	mode \|= SPI_TX_DUAL;
	break;
	case 4:
	mode \|= SPI_TX_QUAD;
	break;
	case 8:
	mode \|= SPI_TX_OCTAL;
	break;
	default:
	warn_non_spl("spi-tx-bus-width %d not supported\n", value);
	break;
	}

	value = dev_read_u32_default(dev, "spi-rx-bus-width", 1);
	switch (value) {
	case 1:
	break;
	case 2:
	mode \|= SPI_RX_DUAL;
	break;
	case 4:
	mode \|= SPI_RX_QUAD;
	break;
	case 8:
	mode \|= SPI_RX_OCTAL;
	break;
	default:
	warn_non_spl("spi-rx-bus-width %d not supported\n", value);
	break;
	}

	plat->mode = mode;

	return 0;
	}

	UCLASS_DRIVER(spi) = {
	.id = UCLASS_SPI,
	.name = "spi",
	.flags = DM_UC_FLAG_SEQ_ALIAS,
	#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
	.post_bind = dm_scan_fdt_dev,
	#endif
	.post_probe = spi_post_probe,
	.child_pre_probe = spi_child_pre_probe,
	.per_device_auto = sizeof(struct dm_spi_bus),
	.per_child_auto = sizeof(struct spi_slave),
	.per_child_plat_auto = sizeof(struct dm_spi_slave_plat),
	#if !CONFIG_IS_ENABLED(OF_PLATDATA)
	.child_post_bind = spi_child_post_bind,
	#endif
	};

	UCLASS_DRIVER(spi_generic) = {
	.id = UCLASS_SPI_GENERIC,
	.name = "spi_generic",
	};

	U_BOOT_DRIVER(spi_generic_drv) = {
	.name = "spi_generic_drv",
	.id = UCLASS_SPI_GENERIC,
	};