drivers/i2c/ihs_i2c.c - platform/external/u-boot - Gitiles

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * (C) Copyright 2013
  * Dirk Eibach,  Guntermann & Drunck GmbH, dirk.eibach@gdsys.cc
  */

 #include <common.h>
 #include <i2c.h>
 #ifdef CONFIG_DM_I2C
 #include <dm.h>
 #include <regmap.h>
 #else
 #include <gdsys_fpga.h>
 #endif
 #include <log.h>
 #include <asm/unaligned.h>

 #ifdef CONFIG_DM_I2C
 struct ihs_i2c_priv {
 	uint speed;
 	struct regmap *map;
 };

 struct ihs_i2c_regs {
 	u16 interrupt_status;
 	u16 interrupt_enable_control;
 	u16 write_mailbox_ext;
 	u16 write_mailbox;
 	u16 read_mailbox_ext;
 	u16 read_mailbox;
 };

 #define ihs_i2c_set(map, member, val) \
 	regmap_set(map, struct ihs_i2c_regs, member, val)

 #define ihs_i2c_get(map, member, valp) \
 	regmap_get(map, struct ihs_i2c_regs, member, valp)

 #else /* !CONFIG_DM_I2C */
 DECLARE_GLOBAL_DATA_PTR;

 #ifdef CONFIG_SYS_I2C_IHS_DUAL

 #define I2C_SET_REG(fld, val) \
 	do { \
 		if (I2C_ADAP_HWNR & 0x10) \
 			FPGA_SET_REG(I2C_ADAP_HWNR & 0xf, i2c1.fld, val); \
 		else \
 			FPGA_SET_REG(I2C_ADAP_HWNR, i2c0.fld, val); \
 	} while (0)
 #else
 #define I2C_SET_REG(fld, val) \
 		FPGA_SET_REG(I2C_ADAP_HWNR, i2c0.fld, val)
 #endif

 #ifdef CONFIG_SYS_I2C_IHS_DUAL
 #define I2C_GET_REG(fld, val) \
 	do {					\
 		if (I2C_ADAP_HWNR & 0x10) \
 			FPGA_GET_REG(I2C_ADAP_HWNR & 0xf, i2c1.fld, val); \
 		else \
 			FPGA_GET_REG(I2C_ADAP_HWNR, i2c0.fld, val); \
 	} while (0)
 #else
 #define I2C_GET_REG(fld, val) \
 		FPGA_GET_REG(I2C_ADAP_HWNR, i2c0.fld, val)
 #endif
 #endif /* CONFIG_DM_I2C */

 enum {
 	I2CINT_ERROR_EV = BIT(13),
 	I2CINT_TRANSMIT_EV = BIT(14),
 	I2CINT_RECEIVE_EV = BIT(15),
 };

 enum {
 	I2CMB_READ = 0 << 10,
 	I2CMB_WRITE = 1 << 10,
 	I2CMB_1BYTE = 0 << 11,
 	I2CMB_2BYTE = 1 << 11,
 	I2CMB_DONT_HOLD_BUS = 0 << 13,
 	I2CMB_HOLD_BUS = 1 << 13,
 	I2CMB_NATIVE = 2 << 14,
 };

 enum {
 	I2COP_WRITE = 0,
 	I2COP_READ = 1,
 };

 #ifdef CONFIG_DM_I2C
 static int wait_for_int(struct udevice *dev, int read)
 #else
 static int wait_for_int(bool read)
 #endif
 {
 	u16 val;
 	uint ctr = 0;
 #ifdef CONFIG_DM_I2C
 	struct ihs_i2c_priv *priv = dev_get_priv(dev);
 #endif

 #ifdef CONFIG_DM_I2C
 	ihs_i2c_get(priv->map, interrupt_status, &val);
 #else
 	I2C_GET_REG(interrupt_status, &val);
 #endif
 	/* Wait until error or receive/transmit interrupt was raised */
 	while (!(val & (I2CINT_ERROR_EV
 	       | (read ? I2CINT_RECEIVE_EV : I2CINT_TRANSMIT_EV)))) {
 		udelay(10);
 		if (ctr++ > 5000) {
 			debug("%s: timed out\n", __func__);
 			return -ETIMEDOUT;
 		}
 #ifdef CONFIG_DM_I2C
 		ihs_i2c_get(priv->map, interrupt_status, &val);
 #else
 		I2C_GET_REG(interrupt_status, &val);
 #endif
 	}

 	return (val & I2CINT_ERROR_EV) ? -EIO : 0;
 }

 #ifdef CONFIG_DM_I2C
 static int ihs_i2c_transfer(struct udevice *dev, uchar chip,
 			    uchar *buffer, int len, int read, bool is_last)
 #else
 static int ihs_i2c_transfer(uchar chip, uchar *buffer, int len, bool read,
 			    bool is_last)
 #endif
 {
 	u16 val;
 	u16 data;
 	int res;
 #ifdef CONFIG_DM_I2C
 	struct ihs_i2c_priv *priv = dev_get_priv(dev);
 #endif

 	/* Clear interrupt status */
 	data = I2CINT_ERROR_EV | I2CINT_RECEIVE_EV | I2CINT_TRANSMIT_EV;
 #ifdef CONFIG_DM_I2C
 	ihs_i2c_set(priv->map, interrupt_status, data);
 	ihs_i2c_get(priv->map, interrupt_status, &val);
 #else
 	I2C_SET_REG(interrupt_status, data);
 	I2C_GET_REG(interrupt_status, &val);
 #endif

 	/* If we want to write and have data, write the bytes to the mailbox */
 	if (!read && len) {
 		val = buffer[0];

 		if (len > 1)
 			val |= buffer[1] << 8;
 #ifdef CONFIG_DM_I2C
 		ihs_i2c_set(priv->map, write_mailbox_ext, val);
 #else
 		I2C_SET_REG(write_mailbox_ext, val);
 #endif
 	}

 	data = I2CMB_NATIVE
 	       | (read ? 0 : I2CMB_WRITE)
 	       | (chip << 1)
 	       | ((len > 1) ? I2CMB_2BYTE : 0)
 	       | (is_last ? 0 : I2CMB_HOLD_BUS);

 #ifdef CONFIG_DM_I2C
 	ihs_i2c_set(priv->map, write_mailbox, data);
 #else
 	I2C_SET_REG(write_mailbox, data);
 #endif

 #ifdef CONFIG_DM_I2C
 	res = wait_for_int(dev, read);
 #else
 	res = wait_for_int(read);
 #endif
 	if (res) {
 		if (res == -ETIMEDOUT)
 			debug("%s: time out while waiting for event\n", __func__);

 		return res;
 	}

 	/* If we want to read, get the bytes from the mailbox */
 	if (read) {
 #ifdef CONFIG_DM_I2C
 		ihs_i2c_get(priv->map, read_mailbox_ext, &val);
 #else
 		I2C_GET_REG(read_mailbox_ext, &val);
 #endif
 		buffer[0] = val & 0xff;
 		if (len > 1)
 			buffer[1] = val >> 8;
 	}

 	return 0;
 }

 #ifdef CONFIG_DM_I2C
 static int ihs_i2c_send_buffer(struct udevice *dev, uchar chip, u8 *data, int len, bool hold_bus, int read)
 #else
 static int ihs_i2c_send_buffer(uchar chip, u8 *data, int len, bool hold_bus,
 			       int read)
 #endif
 {
 	int res;

 	while (len) {
 		int transfer = min(len, 2);
 		bool is_last = len <= transfer;

 #ifdef CONFIG_DM_I2C
 		res = ihs_i2c_transfer(dev, chip, data, transfer, read,
 				       hold_bus ? false : is_last);
 #else
 		res = ihs_i2c_transfer(chip, data, transfer, read,
 				       hold_bus ? false : is_last);
 #endif
 		if (res)
 			return res;

 		data += transfer;
 		len -= transfer;
 	}

 	return 0;
 }

 #ifdef CONFIG_DM_I2C
 static int ihs_i2c_address(struct udevice *dev, uchar chip, u8 *addr, int alen,
 			   bool hold_bus)
 #else
 static int ihs_i2c_address(uchar chip, u8 *addr, int alen, bool hold_bus)
 #endif
 {
 #ifdef CONFIG_DM_I2C
 	return ihs_i2c_send_buffer(dev, chip, addr, alen, hold_bus, I2COP_WRITE);
 #else
 	return ihs_i2c_send_buffer(chip, addr, alen, hold_bus, I2COP_WRITE);
 #endif
 }

 #ifdef CONFIG_DM_I2C
 static int ihs_i2c_access(struct udevice *dev, uchar chip, u8 *addr,
 			  int alen, uchar *buffer, int len, int read)
 #else
 static int ihs_i2c_access(struct i2c_adapter *adap, uchar chip, u8 *addr,
 			  int alen, uchar *buffer, int len, int read)
 #endif
 {
 	int res;

 	/* Don't hold the bus if length of data to send/receive is zero */
 	if (len <= 0)
 		return -EINVAL;

 #ifdef CONFIG_DM_I2C
 	res = ihs_i2c_address(dev, chip, addr, alen, len);
 #else
 	res = ihs_i2c_address(chip, addr, alen, len);
 #endif
 	if (res)
 		return res;

 #ifdef CONFIG_DM_I2C
 	return ihs_i2c_send_buffer(dev, chip, buffer, len, false, read);
 #else
 	return ihs_i2c_send_buffer(chip, buffer, len, false, read);
 #endif
 }

 #ifdef CONFIG_DM_I2C

 int ihs_i2c_probe(struct udevice *bus)
 {
 	struct ihs_i2c_priv *priv = dev_get_priv(bus);

 	regmap_init_mem(dev_ofnode(bus), &priv->map);

 	return 0;
 }

 static int ihs_i2c_set_bus_speed(struct udevice *bus, uint speed)
 {
 	struct ihs_i2c_priv *priv = dev_get_priv(bus);

 	if (speed != priv->speed && priv->speed != 0)
 		return -EINVAL;

 	priv->speed = speed;

 	return 0;
 }

 static int ihs_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs)
 {
 	struct i2c_msg *dmsg, *omsg, dummy;

 	memset(&dummy, 0, sizeof(struct i2c_msg));

 	/* We expect either two messages (one with an offset and one with the
 	 * actucal data) or one message (just data)
 	 */
 	if (nmsgs > 2 || nmsgs == 0) {
 		debug("%s: Only one or two messages are supported\n", __func__);
 		return -ENOTSUPP;
 	}

 	omsg = nmsgs == 1 ? &dummy : msg;
 	dmsg = nmsgs == 1 ? msg : msg + 1;

 	if (dmsg->flags & I2C_M_RD)
 		return ihs_i2c_access(bus, dmsg->addr, omsg->buf,
 				      omsg->len, dmsg->buf, dmsg->len,
 				      I2COP_READ);
 	else
 		return ihs_i2c_access(bus, dmsg->addr, omsg->buf,
 				      omsg->len, dmsg->buf, dmsg->len,
 				      I2COP_WRITE);
 }

 static int ihs_i2c_probe_chip(struct udevice *bus, u32 chip_addr,
 			      u32 chip_flags)
 {
 	uchar buffer[2];
 	int res;

 	res = ihs_i2c_transfer(bus, chip_addr, buffer, 0, I2COP_READ, true);
 	if (res)
 		return res;

 	return 0;
 }

 static const struct dm_i2c_ops ihs_i2c_ops = {
 	.xfer           = ihs_i2c_xfer,
 	.probe_chip     = ihs_i2c_probe_chip,
 	.set_bus_speed  = ihs_i2c_set_bus_speed,
 };

 static const struct udevice_id ihs_i2c_ids[] = {
 	{ .compatible = "gdsys,ihs_i2cmaster", },
 	{ /* sentinel */ }
 };

 U_BOOT_DRIVER(i2c_ihs) = {
 	.name = "i2c_ihs",
 	.id = UCLASS_I2C,
 	.of_match = ihs_i2c_ids,
 	.probe = ihs_i2c_probe,
 	.priv_auto_alloc_size = sizeof(struct ihs_i2c_priv),
 	.ops = &ihs_i2c_ops,
 };

 #else /* CONFIG_DM_I2C */

 static void ihs_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
 {
 #ifdef CONFIG_SYS_I2C_INIT_BOARD
 	/*
 	 * Call board specific i2c bus reset routine before accessing the
 	 * environment, which might be in a chip on that bus. For details
 	 * about this problem see doc/I2C_Edge_Conditions.
 	 */
 	i2c_init_board();
 #endif
 }

 static int ihs_i2c_probe(struct i2c_adapter *adap, uchar chip)
 {
 	uchar buffer[2];
 	int res;

 	res = ihs_i2c_transfer(chip, buffer, 0, I2COP_READ, true);
 	if (res)
 		return res;

 	return 0;
 }

 static int ihs_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
 			int alen, uchar *buffer, int len)
 {
 	u8 addr_bytes[4];

 	put_unaligned_le32(addr, addr_bytes);

 	return ihs_i2c_access(adap, chip, addr_bytes, alen, buffer, len,
 			      I2COP_READ);
 }

 static int ihs_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
 			 int alen, uchar *buffer, int len)
 {
 	u8 addr_bytes[4];

 	put_unaligned_le32(addr, addr_bytes);

 	return ihs_i2c_access(adap, chip, addr_bytes, alen, buffer, len,
 			      I2COP_WRITE);
 }

 static unsigned int ihs_i2c_set_bus_speed(struct i2c_adapter *adap,
 					  unsigned int speed)
 {
 	if (speed != adap->speed)
 		return -EINVAL;
 	return speed;
 }

 /*
  * Register IHS i2c adapters
  */
 #ifdef CONFIG_SYS_I2C_IHS_CH0
 U_BOOT_I2C_ADAP_COMPLETE(ihs0, ihs_i2c_init, ihs_i2c_probe,
 			 ihs_i2c_read, ihs_i2c_write,
 			 ihs_i2c_set_bus_speed,
 			 CONFIG_SYS_I2C_IHS_SPEED_0,
 			 CONFIG_SYS_I2C_IHS_SLAVE_0, 0)
 #ifdef CONFIG_SYS_I2C_IHS_DUAL
 U_BOOT_I2C_ADAP_COMPLETE(ihs0_1, ihs_i2c_init, ihs_i2c_probe,
 			 ihs_i2c_read, ihs_i2c_write,
 			 ihs_i2c_set_bus_speed,
 			 CONFIG_SYS_I2C_IHS_SPEED_0_1,
 			 CONFIG_SYS_I2C_IHS_SLAVE_0_1, 16)
 #endif
 #endif
 #ifdef CONFIG_SYS_I2C_IHS_CH1
 U_BOOT_I2C_ADAP_COMPLETE(ihs1, ihs_i2c_init, ihs_i2c_probe,
 			 ihs_i2c_read, ihs_i2c_write,
 			 ihs_i2c_set_bus_speed,
 			 CONFIG_SYS_I2C_IHS_SPEED_1,
 			 CONFIG_SYS_I2C_IHS_SLAVE_1, 1)
 #ifdef CONFIG_SYS_I2C_IHS_DUAL
 U_BOOT_I2C_ADAP_COMPLETE(ihs1_1, ihs_i2c_init, ihs_i2c_probe,
 			 ihs_i2c_read, ihs_i2c_write,
 			 ihs_i2c_set_bus_speed,
 			 CONFIG_SYS_I2C_IHS_SPEED_1_1,
 			 CONFIG_SYS_I2C_IHS_SLAVE_1_1, 17)
 #endif
 #endif
 #ifdef CONFIG_SYS_I2C_IHS_CH2
 U_BOOT_I2C_ADAP_COMPLETE(ihs2, ihs_i2c_init, ihs_i2c_probe,
 			 ihs_i2c_read, ihs_i2c_write,
 			 ihs_i2c_set_bus_speed,
 			 CONFIG_SYS_I2C_IHS_SPEED_2,
 			 CONFIG_SYS_I2C_IHS_SLAVE_2, 2)
 #ifdef CONFIG_SYS_I2C_IHS_DUAL
 U_BOOT_I2C_ADAP_COMPLETE(ihs2_1, ihs_i2c_init, ihs_i2c_probe,
 			 ihs_i2c_read, ihs_i2c_write,
 			 ihs_i2c_set_bus_speed,
 			 CONFIG_SYS_I2C_IHS_SPEED_2_1,
 			 CONFIG_SYS_I2C_IHS_SLAVE_2_1, 18)
 #endif
 #endif
 #ifdef CONFIG_SYS_I2C_IHS_CH3
 U_BOOT_I2C_ADAP_COMPLETE(ihs3, ihs_i2c_init, ihs_i2c_probe,
 			 ihs_i2c_read, ihs_i2c_write,
 			 ihs_i2c_set_bus_speed,
 			 CONFIG_SYS_I2C_IHS_SPEED_3,
 			 CONFIG_SYS_I2C_IHS_SLAVE_3, 3)
 #ifdef CONFIG_SYS_I2C_IHS_DUAL
 U_BOOT_I2C_ADAP_COMPLETE(ihs3_1, ihs_i2c_init, ihs_i2c_probe,
 			 ihs_i2c_read, ihs_i2c_write,
 			 ihs_i2c_set_bus_speed,
 			 CONFIG_SYS_I2C_IHS_SPEED_3_1,
 			 CONFIG_SYS_I2C_IHS_SLAVE_3_1, 19)
 #endif
 #endif
 #endif /* CONFIG_DM_I2C */
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* (C) Copyright 2013
	* Dirk Eibach, Guntermann & Drunck GmbH, dirk.eibach@gdsys.cc
	*/

	#include <common.h>
	#include <i2c.h>
	#ifdef CONFIG_DM_I2C
	#include <dm.h>
	#include <regmap.h>
	#else
	#include <gdsys_fpga.h>
	#endif
	#include <log.h>
	#include <asm/unaligned.h>

	#ifdef CONFIG_DM_I2C
	struct ihs_i2c_priv {
	uint speed;
	struct regmap *map;
	};

	struct ihs_i2c_regs {
	u16 interrupt_status;
	u16 interrupt_enable_control;
	u16 write_mailbox_ext;
	u16 write_mailbox;
	u16 read_mailbox_ext;
	u16 read_mailbox;
	};

	#define ihs_i2c_set(map, member, val) \
	regmap_set(map, struct ihs_i2c_regs, member, val)

	#define ihs_i2c_get(map, member, valp) \
	regmap_get(map, struct ihs_i2c_regs, member, valp)

	#else /* !CONFIG_DM_I2C */
	DECLARE_GLOBAL_DATA_PTR;

	#ifdef CONFIG_SYS_I2C_IHS_DUAL

	#define I2C_SET_REG(fld, val) \
	do { \
	if (I2C_ADAP_HWNR & 0x10) \
	FPGA_SET_REG(I2C_ADAP_HWNR & 0xf, i2c1.fld, val); \
	else \
	FPGA_SET_REG(I2C_ADAP_HWNR, i2c0.fld, val); \
	} while (0)
	#else
	#define I2C_SET_REG(fld, val) \
	FPGA_SET_REG(I2C_ADAP_HWNR, i2c0.fld, val)
	#endif

	#ifdef CONFIG_SYS_I2C_IHS_DUAL
	#define I2C_GET_REG(fld, val) \
	do { \
	if (I2C_ADAP_HWNR & 0x10) \
	FPGA_GET_REG(I2C_ADAP_HWNR & 0xf, i2c1.fld, val); \
	else \
	FPGA_GET_REG(I2C_ADAP_HWNR, i2c0.fld, val); \
	} while (0)
	#else
	#define I2C_GET_REG(fld, val) \
	FPGA_GET_REG(I2C_ADAP_HWNR, i2c0.fld, val)
	#endif
	#endif /* CONFIG_DM_I2C */

	enum {
	I2CINT_ERROR_EV = BIT(13),
	I2CINT_TRANSMIT_EV = BIT(14),
	I2CINT_RECEIVE_EV = BIT(15),
	};

	enum {
	I2CMB_READ = 0 << 10,
	I2CMB_WRITE = 1 << 10,
	I2CMB_1BYTE = 0 << 11,
	I2CMB_2BYTE = 1 << 11,
	I2CMB_DONT_HOLD_BUS = 0 << 13,
	I2CMB_HOLD_BUS = 1 << 13,
	I2CMB_NATIVE = 2 << 14,
	};

	enum {
	I2COP_WRITE = 0,
	I2COP_READ = 1,
	};

	#ifdef CONFIG_DM_I2C
	static int wait_for_int(struct udevice *dev, int read)
	#else
	static int wait_for_int(bool read)
	#endif
	{
	u16 val;
	uint ctr = 0;
	#ifdef CONFIG_DM_I2C
	struct ihs_i2c_priv *priv = dev_get_priv(dev);
	#endif

	#ifdef CONFIG_DM_I2C
	ihs_i2c_get(priv->map, interrupt_status, &val);
	#else
	I2C_GET_REG(interrupt_status, &val);
	#endif
	/* Wait until error or receive/transmit interrupt was raised */
	while (!(val & (I2CINT_ERROR_EV
	\| (read ? I2CINT_RECEIVE_EV : I2CINT_TRANSMIT_EV)))) {
	udelay(10);
	if (ctr++ > 5000) {
	debug("%s: timed out\n", __func__);
	return -ETIMEDOUT;
	}
	#ifdef CONFIG_DM_I2C
	ihs_i2c_get(priv->map, interrupt_status, &val);
	#else
	I2C_GET_REG(interrupt_status, &val);
	#endif
	}

	return (val & I2CINT_ERROR_EV) ? -EIO : 0;
	}

	#ifdef CONFIG_DM_I2C
	static int ihs_i2c_transfer(struct udevice *dev, uchar chip,
	uchar *buffer, int len, int read, bool is_last)
	#else
	static int ihs_i2c_transfer(uchar chip, uchar *buffer, int len, bool read,
	bool is_last)
	#endif
	{
	u16 val;
	u16 data;
	int res;
	#ifdef CONFIG_DM_I2C
	struct ihs_i2c_priv *priv = dev_get_priv(dev);
	#endif

	/* Clear interrupt status */
	data = I2CINT_ERROR_EV \| I2CINT_RECEIVE_EV \| I2CINT_TRANSMIT_EV;
	#ifdef CONFIG_DM_I2C
	ihs_i2c_set(priv->map, interrupt_status, data);
	ihs_i2c_get(priv->map, interrupt_status, &val);
	#else
	I2C_SET_REG(interrupt_status, data);
	I2C_GET_REG(interrupt_status, &val);
	#endif

	/* If we want to write and have data, write the bytes to the mailbox */
	if (!read && len) {
	val = buffer[0];

	if (len > 1)
	val \|= buffer[1] << 8;
	#ifdef CONFIG_DM_I2C
	ihs_i2c_set(priv->map, write_mailbox_ext, val);
	#else
	I2C_SET_REG(write_mailbox_ext, val);
	#endif
	}

	data = I2CMB_NATIVE
	\| (read ? 0 : I2CMB_WRITE)
	\| (chip << 1)
	\| ((len > 1) ? I2CMB_2BYTE : 0)
	\| (is_last ? 0 : I2CMB_HOLD_BUS);

	#ifdef CONFIG_DM_I2C
	ihs_i2c_set(priv->map, write_mailbox, data);
	#else
	I2C_SET_REG(write_mailbox, data);
	#endif

	#ifdef CONFIG_DM_I2C
	res = wait_for_int(dev, read);
	#else
	res = wait_for_int(read);
	#endif
	if (res) {
	if (res == -ETIMEDOUT)
	debug("%s: time out while waiting for event\n", __func__);

	return res;
	}

	/* If we want to read, get the bytes from the mailbox */
	if (read) {
	#ifdef CONFIG_DM_I2C
	ihs_i2c_get(priv->map, read_mailbox_ext, &val);
	#else
	I2C_GET_REG(read_mailbox_ext, &val);
	#endif
	buffer[0] = val & 0xff;
	if (len > 1)
	buffer[1] = val >> 8;
	}

	return 0;
	}

	#ifdef CONFIG_DM_I2C
	static int ihs_i2c_send_buffer(struct udevice dev, uchar chip, u8 data, int len, bool hold_bus, int read)
	#else
	static int ihs_i2c_send_buffer(uchar chip, u8 *data, int len, bool hold_bus,
	int read)
	#endif
	{
	int res;

	while (len) {
	int transfer = min(len, 2);
	bool is_last = len <= transfer;

	#ifdef CONFIG_DM_I2C
	res = ihs_i2c_transfer(dev, chip, data, transfer, read,
	hold_bus ? false : is_last);
	#else
	res = ihs_i2c_transfer(chip, data, transfer, read,
	hold_bus ? false : is_last);
	#endif
	if (res)
	return res;

	data += transfer;
	len -= transfer;
	}

	return 0;
	}

	#ifdef CONFIG_DM_I2C
	static int ihs_i2c_address(struct udevice dev, uchar chip, u8 addr, int alen,
	bool hold_bus)
	#else
	static int ihs_i2c_address(uchar chip, u8 *addr, int alen, bool hold_bus)
	#endif
	{
	#ifdef CONFIG_DM_I2C
	return ihs_i2c_send_buffer(dev, chip, addr, alen, hold_bus, I2COP_WRITE);
	#else
	return ihs_i2c_send_buffer(chip, addr, alen, hold_bus, I2COP_WRITE);
	#endif
	}

	#ifdef CONFIG_DM_I2C
	static int ihs_i2c_access(struct udevice dev, uchar chip, u8 addr,
	int alen, uchar *buffer, int len, int read)
	#else
	static int ihs_i2c_access(struct i2c_adapter adap, uchar chip, u8 addr,
	int alen, uchar *buffer, int len, int read)
	#endif
	{
	int res;

	/* Don't hold the bus if length of data to send/receive is zero */
	if (len <= 0)
	return -EINVAL;

	#ifdef CONFIG_DM_I2C
	res = ihs_i2c_address(dev, chip, addr, alen, len);
	#else
	res = ihs_i2c_address(chip, addr, alen, len);
	#endif
	if (res)
	return res;

	#ifdef CONFIG_DM_I2C
	return ihs_i2c_send_buffer(dev, chip, buffer, len, false, read);
	#else
	return ihs_i2c_send_buffer(chip, buffer, len, false, read);
	#endif
	}

	#ifdef CONFIG_DM_I2C

	int ihs_i2c_probe(struct udevice *bus)
	{
	struct ihs_i2c_priv *priv = dev_get_priv(bus);

	regmap_init_mem(dev_ofnode(bus), &priv->map);

	return 0;
	}

	static int ihs_i2c_set_bus_speed(struct udevice *bus, uint speed)
	{
	struct ihs_i2c_priv *priv = dev_get_priv(bus);

	if (speed != priv->speed && priv->speed != 0)
	return -EINVAL;

	priv->speed = speed;

	return 0;
	}

	static int ihs_i2c_xfer(struct udevice bus, struct i2c_msg msg, int nmsgs)
	{
	struct i2c_msg dmsg, omsg, dummy;

	memset(&dummy, 0, sizeof(struct i2c_msg));

	/* We expect either two messages (one with an offset and one with the
	* actucal data) or one message (just data)
	*/
	if (nmsgs > 2 \|\| nmsgs == 0) {
	debug("%s: Only one or two messages are supported\n", __func__);
	return -ENOTSUPP;
	}

	omsg = nmsgs == 1 ? &dummy : msg;
	dmsg = nmsgs == 1 ? msg : msg + 1;

	if (dmsg->flags & I2C_M_RD)
	return ihs_i2c_access(bus, dmsg->addr, omsg->buf,
	omsg->len, dmsg->buf, dmsg->len,
	I2COP_READ);
	else
	return ihs_i2c_access(bus, dmsg->addr, omsg->buf,
	omsg->len, dmsg->buf, dmsg->len,
	I2COP_WRITE);
	}

	static int ihs_i2c_probe_chip(struct udevice *bus, u32 chip_addr,
	u32 chip_flags)
	{
	uchar buffer[2];
	int res;

	res = ihs_i2c_transfer(bus, chip_addr, buffer, 0, I2COP_READ, true);
	if (res)
	return res;

	return 0;
	}

	static const struct dm_i2c_ops ihs_i2c_ops = {
	.xfer = ihs_i2c_xfer,
	.probe_chip = ihs_i2c_probe_chip,
	.set_bus_speed = ihs_i2c_set_bus_speed,
	};

	static const struct udevice_id ihs_i2c_ids[] = {
	{ .compatible = "gdsys,ihs_i2cmaster", },
	{ /* sentinel */ }
	};

	U_BOOT_DRIVER(i2c_ihs) = {
	.name = "i2c_ihs",
	.id = UCLASS_I2C,
	.of_match = ihs_i2c_ids,
	.probe = ihs_i2c_probe,
	.priv_auto_alloc_size = sizeof(struct ihs_i2c_priv),
	.ops = &ihs_i2c_ops,
	};

	#else /* CONFIG_DM_I2C */

	static void ihs_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
	{
	#ifdef CONFIG_SYS_I2C_INIT_BOARD
	/*
	* Call board specific i2c bus reset routine before accessing the
	* environment, which might be in a chip on that bus. For details
	* about this problem see doc/I2C_Edge_Conditions.
	*/
	i2c_init_board();
	#endif
	}

	static int ihs_i2c_probe(struct i2c_adapter *adap, uchar chip)
	{
	uchar buffer[2];
	int res;

	res = ihs_i2c_transfer(chip, buffer, 0, I2COP_READ, true);
	if (res)
	return res;

	return 0;
	}

	static int ihs_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
	int alen, uchar *buffer, int len)
	{
	u8 addr_bytes[4];

	put_unaligned_le32(addr, addr_bytes);

	return ihs_i2c_access(adap, chip, addr_bytes, alen, buffer, len,
	I2COP_READ);
	}

	static int ihs_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
	int alen, uchar *buffer, int len)
	{
	u8 addr_bytes[4];

	put_unaligned_le32(addr, addr_bytes);

	return ihs_i2c_access(adap, chip, addr_bytes, alen, buffer, len,
	I2COP_WRITE);
	}

	static unsigned int ihs_i2c_set_bus_speed(struct i2c_adapter *adap,
	unsigned int speed)
	{
	if (speed != adap->speed)
	return -EINVAL;
	return speed;
	}

	/*
	* Register IHS i2c adapters
	*/
	#ifdef CONFIG_SYS_I2C_IHS_CH0
	U_BOOT_I2C_ADAP_COMPLETE(ihs0, ihs_i2c_init, ihs_i2c_probe,
	ihs_i2c_read, ihs_i2c_write,
	ihs_i2c_set_bus_speed,
	CONFIG_SYS_I2C_IHS_SPEED_0,
	CONFIG_SYS_I2C_IHS_SLAVE_0, 0)
	#ifdef CONFIG_SYS_I2C_IHS_DUAL
	U_BOOT_I2C_ADAP_COMPLETE(ihs0_1, ihs_i2c_init, ihs_i2c_probe,
	ihs_i2c_read, ihs_i2c_write,
	ihs_i2c_set_bus_speed,
	CONFIG_SYS_I2C_IHS_SPEED_0_1,
	CONFIG_SYS_I2C_IHS_SLAVE_0_1, 16)
	#endif
	#endif
	#ifdef CONFIG_SYS_I2C_IHS_CH1
	U_BOOT_I2C_ADAP_COMPLETE(ihs1, ihs_i2c_init, ihs_i2c_probe,
	ihs_i2c_read, ihs_i2c_write,
	ihs_i2c_set_bus_speed,
	CONFIG_SYS_I2C_IHS_SPEED_1,
	CONFIG_SYS_I2C_IHS_SLAVE_1, 1)
	#ifdef CONFIG_SYS_I2C_IHS_DUAL
	U_BOOT_I2C_ADAP_COMPLETE(ihs1_1, ihs_i2c_init, ihs_i2c_probe,
	ihs_i2c_read, ihs_i2c_write,
	ihs_i2c_set_bus_speed,
	CONFIG_SYS_I2C_IHS_SPEED_1_1,
	CONFIG_SYS_I2C_IHS_SLAVE_1_1, 17)
	#endif
	#endif
	#ifdef CONFIG_SYS_I2C_IHS_CH2
	U_BOOT_I2C_ADAP_COMPLETE(ihs2, ihs_i2c_init, ihs_i2c_probe,
	ihs_i2c_read, ihs_i2c_write,
	ihs_i2c_set_bus_speed,
	CONFIG_SYS_I2C_IHS_SPEED_2,
	CONFIG_SYS_I2C_IHS_SLAVE_2, 2)
	#ifdef CONFIG_SYS_I2C_IHS_DUAL
	U_BOOT_I2C_ADAP_COMPLETE(ihs2_1, ihs_i2c_init, ihs_i2c_probe,
	ihs_i2c_read, ihs_i2c_write,
	ihs_i2c_set_bus_speed,
	CONFIG_SYS_I2C_IHS_SPEED_2_1,
	CONFIG_SYS_I2C_IHS_SLAVE_2_1, 18)
	#endif
	#endif
	#ifdef CONFIG_SYS_I2C_IHS_CH3
	U_BOOT_I2C_ADAP_COMPLETE(ihs3, ihs_i2c_init, ihs_i2c_probe,
	ihs_i2c_read, ihs_i2c_write,
	ihs_i2c_set_bus_speed,
	CONFIG_SYS_I2C_IHS_SPEED_3,
	CONFIG_SYS_I2C_IHS_SLAVE_3, 3)
	#ifdef CONFIG_SYS_I2C_IHS_DUAL
	U_BOOT_I2C_ADAP_COMPLETE(ihs3_1, ihs_i2c_init, ihs_i2c_probe,
	ihs_i2c_read, ihs_i2c_write,
	ihs_i2c_set_bus_speed,
	CONFIG_SYS_I2C_IHS_SPEED_3_1,
	CONFIG_SYS_I2C_IHS_SLAVE_3_1, 19)
	#endif
	#endif
	#endif /* CONFIG_DM_I2C */