Merge tag '20191217-for-next' of https://gitlab.denx.de/u-boot/custodians/u-boot-i2c into next

i2c: for next
- misc: i2c_eeprom:
  Add partition support and add ability to query size
  of eeprom device and partitions
- i2c common:
  add support for offset overflow in to address and add
  sandbox tests for it.

arch/sandbox/include/asm/test.h

@@ -72,6 +72,13 @@ void sandbox_i2c_eeprom_set_test_mode(struct udevice *dev,
 
 void sandbox_i2c_eeprom_set_offset_len(struct udevice *dev, int offset_len);
 
+void sandbox_i2c_eeprom_set_chip_addr_offset_mask(struct udevice *dev,
+						  uint mask);
+
+uint sanbox_i2c_eeprom_get_prev_addr(struct udevice *dev);
+
+uint sanbox_i2c_eeprom_get_prev_offset(struct udevice *dev);
+
 /**
  * sandbox_i2c_rtc_set_offset() - set the time offset from system/base time
  *

drivers/i2c/i2c-uclass.c

@@ -52,16 +52,19 @@ void i2c_dump_msgs(struct i2c_msg *msg, int nmsgs)
 static int i2c_setup_offset(struct dm_i2c_chip *chip, uint offset,
 			    uint8_t offset_buf[], struct i2c_msg *msg)
 {
-	int offset_len;
+	int offset_len = chip->offset_len;
 
 	msg->addr = chip->chip_addr;
+	if (chip->chip_addr_offset_mask)
+		msg->addr |= (offset >> (8 * offset_len)) &
+			chip->chip_addr_offset_mask;
 	msg->flags = chip->flags & DM_I2C_CHIP_10BIT ? I2C_M_TEN : 0;
 	msg->len = chip->offset_len;
 	msg->buf = offset_buf;
-	if (!chip->offset_len)
+	if (!offset_len)
 		return -EADDRNOTAVAIL;
-	assert(chip->offset_len <= I2C_MAX_OFFSET_LEN);
-	offset_len = chip->offset_len;
+	assert(offset_len <= I2C_MAX_OFFSET_LEN);
+
 	while (offset_len--)
 		*offset_buf++ = offset >> (8 * offset_len);
 
@@ -83,7 +86,7 @@ static int i2c_read_bytewise(struct udevice *dev, uint offset,
 		if (i2c_setup_offset(chip, offset + i, offset_buf, msg))
 			return -EINVAL;
 		ptr = msg + 1;
-		ptr->addr = chip->chip_addr;
+		ptr->addr = msg->addr;
 		ptr->flags = msg->flags | I2C_M_RD;
 		ptr->len = 1;
 		ptr->buf = &buffer[i];
@@ -139,7 +142,7 @@ int dm_i2c_read(struct udevice *dev, uint offset, uint8_t *buffer, int len)
 		ptr++;
 
 	if (len) {
-		ptr->addr = chip->chip_addr;
+		ptr->addr = msg->addr;
 		ptr->flags = chip->flags & DM_I2C_CHIP_10BIT ? I2C_M_TEN : 0;
 		ptr->flags |= I2C_M_RD;
 		ptr->len = len;
@@ -323,7 +326,8 @@ int i2c_get_chip(struct udevice *bus, uint chip_addr, uint offset_len,
 		struct dm_i2c_chip *chip = dev_get_parent_platdata(dev);
 		int ret;
 
-		if (chip->chip_addr == chip_addr) {
+		if (chip->chip_addr == (chip_addr &
+					~chip->chip_addr_offset_mask)) {
 			ret = device_probe(dev);
 			debug("found, ret=%d\n", ret);
 			if (ret)
@@ -465,6 +469,22 @@ int i2c_get_chip_offset_len(struct udevice *dev)
 	return chip->offset_len;
 }
 
+int i2c_set_chip_addr_offset_mask(struct udevice *dev, uint mask)
+{
+	struct dm_i2c_chip *chip = dev_get_parent_platdata(dev);
+
+	chip->chip_addr_offset_mask = mask;
+
+	return 0;
+}
+
+uint i2c_get_chip_addr_offset_mask(struct udevice *dev)
+{
+	struct dm_i2c_chip *chip = dev_get_parent_platdata(dev);
+
+	return chip->chip_addr_offset_mask;
+}
+
 #ifdef CONFIG_DM_GPIO
 static void i2c_gpio_set_pin(struct gpio_desc *pin, int bit)
 {

drivers/misc/i2c_eeprom.c

@@ -8,9 +8,15 @@
 #include <linux/err.h>
 #include <linux/kernel.h>
 #include <dm.h>
+#include <dm/device-internal.h>
 #include <i2c.h>
 #include <i2c_eeprom.h>
 
+struct i2c_eeprom_drv_data {
+	u32 size; /* size in bytes */
+	u32 pagewidth; /* pagesize = 2^pagewidth */
+};
+
 int i2c_eeprom_read(struct udevice *dev, int offset, uint8_t *buf, int size)
 {
 	const struct i2c_eeprom_ops *ops = device_get_ops(dev);
@@ -31,6 +37,16 @@ int i2c_eeprom_write(struct udevice *dev, int offset, uint8_t *buf, int size)
 	return ops->write(dev, offset, buf, size);
 }
 
+int i2c_eeprom_size(struct udevice *dev)
+{
+	const struct i2c_eeprom_ops *ops = device_get_ops(dev);
+
+	if (!ops->size)
+		return -ENOSYS;
+
+	return ops->size(dev);
+}
+
 static int i2c_eeprom_std_read(struct udevice *dev, int offset, uint8_t *buf,
 			       int size)
 {
@@ -60,25 +76,62 @@ static int i2c_eeprom_std_write(struct udevice *dev, int offset,
 	return 0;
 }
 
+static int i2c_eeprom_std_size(struct udevice *dev)
+{
+	struct i2c_eeprom *priv = dev_get_priv(dev);
+
+	return priv->size;
+}
+
 static const struct i2c_eeprom_ops i2c_eeprom_std_ops = {
 	.read	= i2c_eeprom_std_read,
 	.write	= i2c_eeprom_std_write,
+	.size	= i2c_eeprom_std_size,
 };
 
 static int i2c_eeprom_std_ofdata_to_platdata(struct udevice *dev)
 {
 	struct i2c_eeprom *priv = dev_get_priv(dev);
-	u64 data = dev_get_driver_data(dev);
+	struct i2c_eeprom_drv_data *data =
+		(struct i2c_eeprom_drv_data *)dev_get_driver_data(dev);
 	u32 pagesize;
+	u32 size;
 
 	if (dev_read_u32(dev, "pagesize", &pagesize) == 0) {
 		priv->pagesize = pagesize;
-		return 0;
-	}
-
+	} else {
 		/* 6 bit -> page size of up to 2^63 (should be sufficient) */
-	priv->pagewidth = data & 0x3F;
+		priv->pagewidth = data->pagewidth;
 		priv->pagesize = (1 << priv->pagewidth);
+	}
+
+	if (dev_read_u32(dev, "size", &size) == 0)
+		priv->size = size;
+	else
+		priv->size = data->size;
+
+	return 0;
+}
+
+static int i2c_eeprom_std_bind(struct udevice *dev)
+{
+	ofnode partitions = ofnode_find_subnode(dev_ofnode(dev), "partitions");
+	ofnode partition;
+	const char *name;
+
+	if (!ofnode_valid(partitions))
+		return 0;
+	if (!ofnode_device_is_compatible(partitions, "fixed-partitions"))
+		return -ENOTSUPP;
+
+	ofnode_for_each_subnode(partition, partitions) {
+		name = ofnode_get_name(partition);
+		if (!name)
+			continue;
+
+		device_bind_ofnode(dev, DM_GET_DRIVER(i2c_eeprom_partition),
+				   name, NULL, partition, NULL);
+	}
 
 	return 0;
 }
@@ -96,21 +149,91 @@ static int i2c_eeprom_std_probe(struct udevice *dev)
 	return 0;
 }
 
+static const struct i2c_eeprom_drv_data eeprom_data = {
+	.size = 0,
+	.pagewidth = 0,
+};
+
+static const struct i2c_eeprom_drv_data mc24aa02e48_data = {
+	.size = 256,
+	.pagewidth = 3,
+};
+
+static const struct i2c_eeprom_drv_data atmel24c01a_data = {
+	.size = 128,
+	.pagewidth = 3,
+};
+
+static const struct i2c_eeprom_drv_data atmel24c02_data = {
+	.size = 256,
+	.pagewidth = 3,
+};
+
+static const struct i2c_eeprom_drv_data atmel24c04_data = {
+	.size = 512,
+	.pagewidth = 4,
+};
+
+static const struct i2c_eeprom_drv_data atmel24c08_data = {
+	.size = 1024,
+	.pagewidth = 4,
+};
+
+static const struct i2c_eeprom_drv_data atmel24c08a_data = {
+	.size = 1024,
+	.pagewidth = 4,
+};
+
+static const struct i2c_eeprom_drv_data atmel24c16a_data = {
+	.size = 2048,
+	.pagewidth = 4,
+};
+
+static const struct i2c_eeprom_drv_data atmel24mac402_data = {
+	.size = 256,
+	.pagewidth = 4,
+};
+
+static const struct i2c_eeprom_drv_data atmel24c32_data = {
+	.size = 4096,
+	.pagewidth = 5,
+};
+
+static const struct i2c_eeprom_drv_data atmel24c64_data = {
+	.size = 8192,
+	.pagewidth = 5,
+};
+
+static const struct i2c_eeprom_drv_data atmel24c128_data = {
+	.size = 16384,
+	.pagewidth = 6,
+};
+
+static const struct i2c_eeprom_drv_data atmel24c256_data = {
+	.size = 32768,
+	.pagewidth = 6,
+};
+
+static const struct i2c_eeprom_drv_data atmel24c512_data = {
+	.size = 65536,
+	.pagewidth = 6,
+};
+
 static const struct udevice_id i2c_eeprom_std_ids[] = {
-	{ .compatible = "i2c-eeprom", .data = 0 },
-	{ .compatible = "microchip,24aa02e48", .data = 3 },
-	{ .compatible = "atmel,24c01a", .data = 3 },
-	{ .compatible = "atmel,24c02", .data = 3 },
-	{ .compatible = "atmel,24c04", .data = 4 },
-	{ .compatible = "atmel,24c08", .data = 4 },
-	{ .compatible = "atmel,24c08a", .data = 4 },
-	{ .compatible = "atmel,24c16a", .data = 4 },
-	{ .compatible = "atmel,24mac402", .data = 4 },
-	{ .compatible = "atmel,24c32", .data = 5 },
-	{ .compatible = "atmel,24c64", .data = 5 },
-	{ .compatible = "atmel,24c128", .data = 6 },
-	{ .compatible = "atmel,24c256", .data = 6 },
-	{ .compatible = "atmel,24c512", .data = 6 },
+	{ .compatible = "i2c-eeprom", (ulong)&eeprom_data },
+	{ .compatible = "microchip,24aa02e48", (ulong)&mc24aa02e48_data },
+	{ .compatible = "atmel,24c01a", (ulong)&atmel24c01a_data },
+	{ .compatible = "atmel,24c02", (ulong)&atmel24c02_data },
+	{ .compatible = "atmel,24c04", (ulong)&atmel24c04_data },
+	{ .compatible = "atmel,24c08", (ulong)&atmel24c08_data },
+	{ .compatible = "atmel,24c08a", (ulong)&atmel24c08a_data },
+	{ .compatible = "atmel,24c16a", (ulong)&atmel24c16a_data },
+	{ .compatible = "atmel,24mac402", (ulong)&atmel24mac402_data },
+	{ .compatible = "atmel,24c32", (ulong)&atmel24c32_data },
+	{ .compatible = "atmel,24c64", (ulong)&atmel24c64_data },
+	{ .compatible = "atmel,24c128", (ulong)&atmel24c128_data },
+	{ .compatible = "atmel,24c256", (ulong)&atmel24c256_data },
+	{ .compatible = "atmel,24c512", (ulong)&atmel24c512_data },
 	{ }
 };
 
@@ -118,12 +241,94 @@ U_BOOT_DRIVER(i2c_eeprom_std) = {
 	.name			= "i2c_eeprom",
 	.id			= UCLASS_I2C_EEPROM,
 	.of_match		= i2c_eeprom_std_ids,
+	.bind			= i2c_eeprom_std_bind,
 	.probe			= i2c_eeprom_std_probe,
 	.ofdata_to_platdata	= i2c_eeprom_std_ofdata_to_platdata,
 	.priv_auto_alloc_size	= sizeof(struct i2c_eeprom),
 	.ops			= &i2c_eeprom_std_ops,
 };
 
+struct i2c_eeprom_partition {
+	u32 offset;
+	u32 size;
+};
+
+static int i2c_eeprom_partition_probe(struct udevice *dev)
+{
+	return 0;
+}
+
+static int i2c_eeprom_partition_ofdata_to_platdata(struct udevice *dev)
+{
+	struct i2c_eeprom_partition *priv = dev_get_priv(dev);
+	u32 offset, size;
+	int ret;
+
+	ret = dev_read_u32(dev, "offset", &offset);
+	if (ret)
+		return ret;
+
+	ret = dev_read_u32(dev, "size", &size);
+	if (ret)
+		return ret;
+
+	priv->offset = offset;
+	priv->size = size;
+
+	return 0;
+}
+
+static int i2c_eeprom_partition_read(struct udevice *dev, int offset,
+				     u8 *buf, int size)
+{
+	struct i2c_eeprom_partition *priv = dev_get_priv(dev);
+	struct udevice *parent = dev_get_parent(dev);
+
+	if (!parent)
+		return -ENODEV;
+	if (offset + size > priv->size)
+		return -EINVAL;
+
+	return i2c_eeprom_read(parent, offset + priv->offset, buf, size);
+}
+
+static int i2c_eeprom_partition_write(struct udevice *dev, int offset,
+				      const u8 *buf, int size)
+{
+	struct i2c_eeprom_partition *priv = dev_get_priv(dev);
+	struct udevice *parent = dev_get_parent(dev);
+
+	if (!parent)
+		return -ENODEV;
+	if (offset + size > priv->size)
+		return -EINVAL;
+
+	return i2c_eeprom_write(parent, offset + priv->offset, (uint8_t *)buf,
+				size);
+}
+
+static int i2c_eeprom_partition_size(struct udevice *dev)
+{
+	struct i2c_eeprom_partition *priv = dev_get_priv(dev);
+
+	return priv->size;
+}
+
+static const struct i2c_eeprom_ops i2c_eeprom_partition_ops = {
+	.read	= i2c_eeprom_partition_read,
+	.write	= i2c_eeprom_partition_write,
+	.size	= i2c_eeprom_partition_size,
+};
+
+U_BOOT_DRIVER(i2c_eeprom_partition) = {
+	.name			= "i2c_eeprom_partition",
+	.id			= UCLASS_I2C_EEPROM,
+	.probe			= i2c_eeprom_partition_probe,
+	.ofdata_to_platdata	= i2c_eeprom_partition_ofdata_to_platdata,
+	.priv_auto_alloc_size	= sizeof(struct i2c_eeprom_partition),
+	.ops			= &i2c_eeprom_partition_ops,
+};
+
 UCLASS_DRIVER(i2c_eeprom) = {
 	.id		= UCLASS_I2C_EEPROM,
 	.name		= "i2c_eeprom",

drivers/misc/i2c_eeprom_emul.c

@@ -23,10 +23,13 @@ struct sandbox_i2c_flash_plat_data {
 	const char *filename;
 	int offset_len;		/* Length of an offset in bytes */
 	int size;		/* Size of data buffer */
+	uint chip_addr_offset_mask; /* mask of addr bits used for offset */
 };
 
 struct sandbox_i2c_flash {
 	uint8_t *data;
+	uint prev_addr;		/* slave address of previous access */
+	uint prev_offset;	/* offset of previous access */
 };
 
 void sandbox_i2c_eeprom_set_test_mode(struct udevice *dev,
@@ -44,36 +47,65 @@ void sandbox_i2c_eeprom_set_offset_len(struct udevice *dev, int offset_len)
 	plat->offset_len = offset_len;
 }
 
+void sandbox_i2c_eeprom_set_chip_addr_offset_mask(struct udevice *dev,
+						  uint mask)
+{
+	struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(dev);
+
+	plat->chip_addr_offset_mask = mask;
+}
+
+uint sanbox_i2c_eeprom_get_prev_addr(struct udevice *dev)
+{
+	struct sandbox_i2c_flash *priv = dev_get_priv(dev);
+
+	return priv->prev_addr;
+}
+
+uint sanbox_i2c_eeprom_get_prev_offset(struct udevice *dev)
+{
+	struct sandbox_i2c_flash *priv = dev_get_priv(dev);
+
+	return priv->prev_offset;
+}
+
 static int sandbox_i2c_eeprom_xfer(struct udevice *emul, struct i2c_msg *msg,
 				  int nmsgs)
 {
 	struct sandbox_i2c_flash *priv = dev_get_priv(emul);
-	uint offset = 0;
+	struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(emul);
+	uint offset = msg->addr & plat->chip_addr_offset_mask;
 
 	debug("\n%s\n", __func__);
 	debug_buffer(0, priv->data, 1, 16, 0);
+
+	/* store addr for testing visibity */
+	priv->prev_addr = msg->addr;
+
 	for (; nmsgs > 0; nmsgs--, msg++) {
-		struct sandbox_i2c_flash_plat_data *plat =
-				dev_get_platdata(emul);
 		int len;
 		u8 *ptr;
 
 		if (!plat->size)
 			return -ENODEV;
-		if (msg->addr + msg->len > plat->size) {
-			debug("%s: Address %x, len %x is outside range 0..%x\n",
-			      __func__, msg->addr, msg->len, plat->size);
-			return -EINVAL;
-		}
 		len = msg->len;
-		debug("   %s: msg->len=%d",
+		debug("   %s: msg->addr=%x msg->len=%d",
 		      msg->flags & I2C_M_RD ? "read" : "write",
-		      msg->len);
+		      msg->addr, msg->len);
 		if (msg->flags & I2C_M_RD) {
 			if (plat->test_mode == SIE_TEST_MODE_SINGLE_BYTE)
 				len = 1;
 			debug(", offset %x, len %x: ", offset, len);
+			if (offset + len > plat->size) {
+				int overflow = offset + len - plat->size;
+				int initial = len - overflow;
+
+				memcpy(msg->buf, priv->data + offset, initial);
+				memcpy(msg->buf + initial, priv->data,
+				       overflow);
+			} else {
 				memcpy(msg->buf, priv->data + offset, len);
+			}
 			memset(msg->buf + len, '\xff', msg->len - len);
 			debug_buffer(0, msg->buf, 1, msg->len, 0);
 		} else if (len >= plat->offset_len) {
@@ -87,17 +119,26 @@ static int sandbox_i2c_eeprom_xfer(struct udevice *emul, struct i2c_msg *msg,
 			if (plat->test_mode == SIE_TEST_MODE_SINGLE_BYTE)
 				len = min(len, 1);
 
-			/* For testing, map offsets into our limited buffer */
-			for (i = 24; i > 0; i -= 8) {
-				if (offset > (1 << i)) {
-					offset = (offset >> i) |
-						(offset & ((1 << i) - 1));
-					offset += i;
-				}
-			}
+			/* store offset for testing visibility */
+			priv->prev_offset = offset;
+
+			/* For testing, map offsets into our limited buffer.
+			 * offset wraps every 256 bytes
+			 */
+			offset &= 0xff;
+			debug("mapped offset to %x\n", offset);
+
+			if (offset + len > plat->size) {
+				int overflow = offset + len - plat->size;
+				int initial = len - overflow;
+
+				memcpy(priv->data + offset, ptr, initial);
+				memcpy(priv->data, ptr + initial, overflow);
+			} else {
 				memcpy(priv->data + offset, ptr, len);
 			}
 		}
+	}
 	debug_buffer(0, priv->data, 1, 16, 0);
 
 	return 0;
@@ -120,6 +161,7 @@ static int sandbox_i2c_eeprom_ofdata_to_platdata(struct udevice *dev)
 	}
 	plat->test_mode = SIE_TEST_MODE_NONE;
 	plat->offset_len = 1;
+	plat->chip_addr_offset_mask = 0;
 
 	return 0;
 }

include/i2c.h

@@ -45,12 +45,26 @@ struct udevice;
  *		represent up to 256 bytes. A value larger than 1 may be
  *		needed for larger devices.
  * @flags:	Flags for this chip (dm_i2c_chip_flags)
+ * @chip_addr_offset_mask: Mask of offset bits within chip_addr. Used for
+ *			   devices which steal addresses as part of offset.
+ *			   If offset_len is zero, then the offset is encoded
+ *			   completely within the chip address itself.
+ *			   e.g. a devce with chip address of 0x2c with 512
+ *			   registers might use the bottom bit of the address
+ *			   to indicate which half of the address space is being
+ *			   accessed while still only using 1 byte offset.
+ *			   This means it will respond to  chip address 0x2c and
+ *			   0x2d.
+ *			   A real world example is the Atmel AT24C04. It's
+ *			   datasheet explains it's usage of this addressing
+ *			   mode.
  * @emul: Emulator for this chip address (only used for emulation)
  */
 struct dm_i2c_chip {
 	uint chip_addr;
 	uint offset_len;
 	uint flags;
+	uint chip_addr_offset_mask;
 #ifdef CONFIG_SANDBOX
 	struct udevice *emul;
 	bool test_mode;
@@ -261,6 +275,25 @@ int i2c_set_chip_offset_len(struct udevice *dev, uint offset_len);
  */
 int i2c_get_chip_offset_len(struct udevice *dev);
 
+/**
+ * i2c_set_chip_addr_offset_mask() - set mask of address bits usable by offset
+ *
+ * Some devices listen on multiple chip addresses to achieve larger offsets
+ * than their single or multiple byte offsets would allow for. You can use this
+ * function to set the bits that are valid to be used for offset overflow.
+ *
+ * @mask: The mask to be used for high offset bits within address
+ * @return 0 if OK, other -ve value on error
+ */
+int i2c_set_chip_addr_offset_mask(struct udevice *dev, uint mask);
+
+/*
+ * i2c_get_chip_addr_offset_mask() - get mask of address bits usable by offset
+ *
+ * @return current chip addr offset mask
+ */
+uint i2c_get_chip_addr_offset_mask(struct udevice *dev);
+
 /**
  * i2c_deblock() - recover a bus that is in an unknown state
  *

include/i2c_eeprom.h

@@ -10,6 +10,7 @@ struct i2c_eeprom_ops {
 	int (*read)(struct udevice *dev, int offset, uint8_t *buf, int size);
 	int (*write)(struct udevice *dev, int offset, const uint8_t *buf,
 		     int size);
+	int (*size)(struct udevice *dev);
 };
 
 struct i2c_eeprom {
@@ -17,6 +18,8 @@ struct i2c_eeprom {
 	unsigned long pagesize;
 	/* The EEPROM's page width in bits (pagesize = 2^pagewidth) */
 	unsigned pagewidth;
+	/* The EEPROM's capacity in bytes */
+	unsigned long size;
 };
 
 /*
@@ -43,4 +46,13 @@ int i2c_eeprom_read(struct udevice *dev, int offset, uint8_t *buf, int size);
  */
 int i2c_eeprom_write(struct udevice *dev, int offset, uint8_t *buf, int size);
 
+/*
+ * i2c_eeprom_size() - get size of I2C EEPROM chip
+ *
+ * @dev:	Chip to query
+ *
+ * @return +ve size in bytes on success, -ve on failure
+ */
+int i2c_eeprom_size(struct udevice *dev);
+
 #endif

test/dm/i2c.c

@@ -15,6 +15,7 @@
 #include <dm/test.h>
 #include <dm/uclass-internal.h>
 #include <dm/util.h>
+#include <hexdump.h>
 #include <test/ut.h>
 
 static const int busnum;
@@ -185,39 +186,123 @@ static int dm_test_i2c_offset(struct unit_test_state *uts)
 	ut_assertok(i2c_set_chip_offset_len(dev, 0));
 	ut_assertok(dm_i2c_write(dev, 10 /* ignored */, (uint8_t *)"AB", 2));
 	ut_assertok(dm_i2c_read(dev, 0, buf, 5));
-	ut_assertok(memcmp(buf, "AB\0\0\0\0", sizeof(buf)));
+	ut_asserteq_mem("AB\0\0\0\0", buf, sizeof(buf));
+	ut_asserteq(0, sanbox_i2c_eeprom_get_prev_offset(eeprom));
 
 	/* Offset length 1 */
 	sandbox_i2c_eeprom_set_offset_len(eeprom, 1);
 	ut_assertok(i2c_set_chip_offset_len(dev, 1));
 	ut_assertok(dm_i2c_write(dev, 2, (uint8_t *)"AB", 2));
+	ut_asserteq(2, sanbox_i2c_eeprom_get_prev_offset(eeprom));
 	ut_assertok(dm_i2c_read(dev, 0, buf, 5));
-	ut_assertok(memcmp(buf, "ABAB\0", sizeof(buf)));
+	ut_asserteq_mem("ABAB\0", buf, sizeof(buf));
+	ut_asserteq(0, sanbox_i2c_eeprom_get_prev_offset(eeprom));
 
-	/* Offset length 2 */
+	/* Offset length 2 boundary - check model wrapping */
 	sandbox_i2c_eeprom_set_offset_len(eeprom, 2);
 	ut_assertok(i2c_set_chip_offset_len(dev, 2));
-	ut_assertok(dm_i2c_write(dev, 0x210, (uint8_t *)"AB", 2));
-	ut_assertok(dm_i2c_read(dev, 0x210, buf, 5));
-	ut_assertok(memcmp(buf, "AB\0\0\0", sizeof(buf)));
+	ut_assertok(dm_i2c_write(dev, 0xFF, (uint8_t *)"A", 1));
+	ut_asserteq(0xFF, sanbox_i2c_eeprom_get_prev_offset(eeprom));
+	ut_assertok(dm_i2c_write(dev, 0x100, (uint8_t *)"B", 1));
+	ut_asserteq(0x100, sanbox_i2c_eeprom_get_prev_offset(eeprom));
+	ut_assertok(dm_i2c_write(dev, 0x101, (uint8_t *)"C", 1));
+	ut_asserteq(0x101, sanbox_i2c_eeprom_get_prev_offset(eeprom));
+	ut_assertok(dm_i2c_read(dev, 0xFF, buf, 5));
+	ut_asserteq_mem("ABCAB", buf, sizeof(buf));
+	ut_asserteq(0xFF, sanbox_i2c_eeprom_get_prev_offset(eeprom));
 
-	/* Offset length 3 */
+	/* Offset length 2 */
 	sandbox_i2c_eeprom_set_offset_len(eeprom, 2);
 	ut_assertok(i2c_set_chip_offset_len(dev, 2));
-	ut_assertok(dm_i2c_write(dev, 0x410, (uint8_t *)"AB", 2));
-	ut_assertok(dm_i2c_read(dev, 0x410, buf, 5));
-	ut_assertok(memcmp(buf, "AB\0\0\0", sizeof(buf)));
+	ut_assertok(dm_i2c_write(dev, 0x2020, (uint8_t *)"AB", 2));
+	ut_assertok(dm_i2c_read(dev, 0x2020, buf, 5));
+	ut_asserteq_mem("AB\0\0\0", buf, sizeof(buf));
+	ut_asserteq(0x2020, sanbox_i2c_eeprom_get_prev_offset(eeprom));
+
+	/* Offset length 3 */
+	sandbox_i2c_eeprom_set_offset_len(eeprom, 3);
+	ut_assertok(i2c_set_chip_offset_len(dev, 3));
+	ut_assertok(dm_i2c_write(dev, 0x303030, (uint8_t *)"AB", 2));
+	ut_assertok(dm_i2c_read(dev, 0x303030, buf, 5));
+	ut_asserteq_mem("AB\0\0\0", buf, sizeof(buf));
+	ut_asserteq(0x303030, sanbox_i2c_eeprom_get_prev_offset(eeprom));
 
 	/* Offset length 4 */
+	sandbox_i2c_eeprom_set_offset_len(eeprom, 4);
+	ut_assertok(i2c_set_chip_offset_len(dev, 4));
+	ut_assertok(dm_i2c_write(dev, 0x40404040, (uint8_t *)"AB", 2));
+	ut_assertok(dm_i2c_read(dev, 0x40404040, buf, 5));
+	ut_asserteq_mem("AB\0\0\0", buf, sizeof(buf));
+	ut_asserteq(0x40404040, sanbox_i2c_eeprom_get_prev_offset(eeprom));
+
+	/* Restore defaults */
+	sandbox_i2c_eeprom_set_offset_len(eeprom, 1);
+
+	return 0;
+}
+DM_TEST(dm_test_i2c_offset, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+static int dm_test_i2c_addr_offset(struct unit_test_state *uts)
+{
+	struct udevice *eeprom;
+	struct udevice *dev;
+	u8 buf[5];
+
+	ut_assertok(i2c_get_chip_for_busnum(busnum, chip, 1, &dev));
+
+	/* Do a transfer so we can find the emulator */
+	ut_assertok(dm_i2c_read(dev, 0, buf, 5));
+	ut_assertok(uclass_first_device(UCLASS_I2C_EMUL, &eeprom));
+
+	/* Offset length 0 */
+	sandbox_i2c_eeprom_set_offset_len(eeprom, 0);
+	sandbox_i2c_eeprom_set_chip_addr_offset_mask(eeprom, 0x3);
+	ut_assertok(i2c_set_chip_offset_len(dev, 0));
+	ut_assertok(i2c_set_chip_addr_offset_mask(dev, 0x3));
+	ut_assertok(dm_i2c_write(dev, 0x3, (uint8_t *)"AB", 2));
+	ut_assertok(dm_i2c_read(dev, 0x3, buf, 5));
+	ut_asserteq_mem("AB\0\0\0\0", buf, sizeof(buf));
+	ut_asserteq(0x3, sanbox_i2c_eeprom_get_prev_offset(eeprom));
+	ut_asserteq(chip | 0x3, sanbox_i2c_eeprom_get_prev_addr(eeprom));
+
+	/* Offset length 1 */
+	sandbox_i2c_eeprom_set_offset_len(eeprom, 1);
+	sandbox_i2c_eeprom_set_chip_addr_offset_mask(eeprom, 0x3);
+	ut_assertok(i2c_set_chip_offset_len(dev, 1));
+	ut_assertok(i2c_set_chip_addr_offset_mask(dev, 0x3));
+	ut_assertok(dm_i2c_write(dev, 0x310, (uint8_t *)"AB", 2));
+	ut_assertok(dm_i2c_read(dev, 0x310, buf, 5));
+	ut_asserteq_mem("AB\0\0\0\0", buf, sizeof(buf));
+	ut_asserteq(0x310, sanbox_i2c_eeprom_get_prev_offset(eeprom));
+	ut_asserteq(chip | 0x3, sanbox_i2c_eeprom_get_prev_addr(eeprom));
+
+	/* Offset length 2 */
 	sandbox_i2c_eeprom_set_offset_len(eeprom, 2);
+	sandbox_i2c_eeprom_set_chip_addr_offset_mask(eeprom, 0x3);
 	ut_assertok(i2c_set_chip_offset_len(dev, 2));
-	ut_assertok(dm_i2c_write(dev, 0x420, (uint8_t *)"AB", 2));
-	ut_assertok(dm_i2c_read(dev, 0x420, buf, 5));
-	ut_assertok(memcmp(buf, "AB\0\0\0", sizeof(buf)));
+	ut_assertok(i2c_set_chip_addr_offset_mask(dev, 0x3));
+	ut_assertok(dm_i2c_write(dev, 0x32020, (uint8_t *)"AB", 2));
+	ut_assertok(dm_i2c_read(dev, 0x32020, buf, 5));
+	ut_asserteq_mem("AB\0\0\0\0", buf, sizeof(buf));
+	ut_asserteq(0x32020, sanbox_i2c_eeprom_get_prev_offset(eeprom));
+	ut_asserteq(chip | 0x3, sanbox_i2c_eeprom_get_prev_addr(eeprom));
+
+	/* Offset length 3 */
+	sandbox_i2c_eeprom_set_offset_len(eeprom, 3);
+	sandbox_i2c_eeprom_set_chip_addr_offset_mask(eeprom, 0x3);
+	ut_assertok(i2c_set_chip_offset_len(dev, 3));
+	ut_assertok(i2c_set_chip_addr_offset_mask(dev, 0x3));
+	ut_assertok(dm_i2c_write(dev, 0x3303030, (uint8_t *)"AB", 2));
+	ut_assertok(dm_i2c_read(dev, 0x3303030, buf, 5));
+	ut_asserteq_mem("AB\0\0\0\0", buf, sizeof(buf));
+	ut_asserteq(0x3303030, sanbox_i2c_eeprom_get_prev_offset(eeprom));
+	ut_asserteq(chip | 0x3, sanbox_i2c_eeprom_get_prev_addr(eeprom));
 
 	/* Restore defaults */
 	sandbox_i2c_eeprom_set_offset_len(eeprom, 1);
+	sandbox_i2c_eeprom_set_chip_addr_offset_mask(eeprom, 0);
 
 	return 0;
 }
-DM_TEST(dm_test_i2c_offset, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+DM_TEST(dm_test_i2c_addr_offset, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);