Patchwork [U-Boot,1/3] i2c: add i2c_core and prepare for new multibus support

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Submitter Heiko Schocher
Date Oct. 22, 2012, 5:40 p.m.
Message ID <1350927621-12481-2-git-send-email-hs@denx.de>
Download mbox | patch
Permalink /patch/193249/
State Superseded
Delegated to: Heiko Schocher
Headers show

Comments

Heiko Schocher - Oct. 22, 2012, 5:40 p.m.
This Patch introduce the new i2c_core file, which holds
the I2C core functions, for the rework of the multibus/
multiadapter support.
Also adds changes in i2c.h for the new I2C multibus/multiadapter
support. This new support can be activated with the
CONFIG_SYS_I2C define.

Signed-off-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Simon Glass <sjg@chromium.org>
Cc: Mike Frysinger <vapier@gentoo.org>

---
- changes against Simons patches:
  - gd->cur_i2c_adap now used as "struct i2c_bus_hose *"
  - get rid of "i2c_cur_bus"
  add comments from Mike Frysinger:
  - renamed cur_adap to cur_i2c_adap
  - use uintx_t types
---
 arch/arm/include/asm/global_data.h        |    3 +
 arch/avr32/include/asm/global_data.h      |    3 +
 arch/blackfin/include/asm/global_data.h   |    4 +-
 arch/m68k/include/asm/global_data.h       |    3 +
 arch/microblaze/include/asm/global_data.h |    3 +
 arch/mips/include/asm/global_data.h       |    3 +
 arch/nds32/include/asm/global_data.h      |    3 +
 arch/nios2/include/asm/global_data.h      |    3 +
 arch/powerpc/include/asm/global_data.h    |    3 +
 arch/sh/include/asm/global_data.h         |    3 +
 arch/sparc/include/asm/global_data.h      |    3 +
 arch/x86/include/asm/global_data.h        |    3 +
 drivers/i2c/Makefile                      |    1 +
 drivers/i2c/i2c_core.c                    |  363 +++++++++++++++++++++++++++++
 include/i2c.h                             |  196 +++++++++++++++-
 15 files changed, 588 insertions(+), 9 deletions(-)
 create mode 100644 drivers/i2c/i2c_core.c

Patch

diff --git a/arch/arm/include/asm/global_data.h b/arch/arm/include/asm/global_data.h
index f8088fe..bc97520 100644
--- a/arch/arm/include/asm/global_data.h
+++ b/arch/arm/include/asm/global_data.h
@@ -82,6 +82,9 @@  typedef	struct	global_data {
 	unsigned long	post_log_res; /* success of POST test */
 	unsigned long	post_init_f_time; /* When post_init_f started */
 #endif
+#if defined(CONFIG_SYS_I2C)
+	void		*cur_i2c_bus;	/* current used i2c bus */
+#endif
 } gd_t;
 
 #include <asm-generic/global_data_flags.h>
diff --git a/arch/avr32/include/asm/global_data.h b/arch/avr32/include/asm/global_data.h
index 7878bb1..e7da6e4 100644
--- a/arch/avr32/include/asm/global_data.h
+++ b/arch/avr32/include/asm/global_data.h
@@ -48,6 +48,9 @@  typedef	struct	global_data {
 #endif
 	void		**jt;		/* jump table */
 	char		env_buf[32];	/* buffer for getenv() before reloc. */
+#if defined(CONFIG_SYS_I2C)
+	void		*cur_i2c_bus;	/* current used i2c bus */
+#endif
 } gd_t;
 
 #include <asm-generic/global_data_flags.h>
diff --git a/arch/blackfin/include/asm/global_data.h b/arch/blackfin/include/asm/global_data.h
index 290a9e7..f08f493 100644
--- a/arch/blackfin/include/asm/global_data.h
+++ b/arch/blackfin/include/asm/global_data.h
@@ -54,9 +54,11 @@  typedef struct global_data {
 	unsigned long post_log_res; 	/* success of POST test */
 	unsigned long post_init_f_time;	/* When post_init_f started */
 #endif
-
 	void	**jt;			/* jump table */
 	char	env_buf[32];		/* buffer for getenv() before reloc. */
+#if defined(CONFIG_SYS_I2C)
+	void		*cur_i2c_bus;	/* current used i2c bus */
+#endif
 } gd_t;
 
 #include <asm-generic/global_data_flags.h>
diff --git a/arch/m68k/include/asm/global_data.h b/arch/m68k/include/asm/global_data.h
index cd55b83..e976bbf 100644
--- a/arch/m68k/include/asm/global_data.h
+++ b/arch/m68k/include/asm/global_data.h
@@ -66,6 +66,9 @@  typedef	struct	global_data {
 #endif
 	void		**jt;		/* Standalone app jump table */
 	char		env_buf[32];	/* buffer for getenv() before reloc. */
+#if defined(CONFIG_SYS_I2C)
+	void		*cur_i2c_bus;	/* current used i2c bus */
+#endif
 } gd_t;
 
 #include <asm-generic/global_data_flags.h>
diff --git a/arch/microblaze/include/asm/global_data.h b/arch/microblaze/include/asm/global_data.h
index de3b8db..eb5ded5 100644
--- a/arch/microblaze/include/asm/global_data.h
+++ b/arch/microblaze/include/asm/global_data.h
@@ -46,6 +46,9 @@  typedef	struct	global_data {
 	unsigned long	fb_base;	/* base address of frame buffer */
 	void		**jt;		/* jump table */
 	char		env_buf[32];	/* buffer for getenv() before reloc. */
+#if defined(CONFIG_SYS_I2C)
+	void		*cur_i2c_bus;	/* current used i2c bus */
+#endif
 } gd_t;
 
 #include <asm-generic/global_data_flags.h>
diff --git a/arch/mips/include/asm/global_data.h b/arch/mips/include/asm/global_data.h
index 6e2cdc7..ad23587 100644
--- a/arch/mips/include/asm/global_data.h
+++ b/arch/mips/include/asm/global_data.h
@@ -59,6 +59,9 @@  typedef	struct	global_data {
 	unsigned long	env_valid;	/* Checksum of Environment valid? */
 	void		**jt;		/* jump table */
 	char		env_buf[32];	/* buffer for getenv() before reloc. */
+#if defined(CONFIG_SYS_I2C)
+	void		*cur_i2c_bus;	/* current used i2c bus */
+#endif
 } gd_t;
 
 #include <asm-generic/global_data_flags.h>
diff --git a/arch/nds32/include/asm/global_data.h b/arch/nds32/include/asm/global_data.h
index 94bd4c2..bac218e 100644
--- a/arch/nds32/include/asm/global_data.h
+++ b/arch/nds32/include/asm/global_data.h
@@ -63,6 +63,9 @@  typedef	struct global_data {
 
 	void		**jt;		/* jump table */
 	char		env_buf[32];	/* buffer for getenv() before reloc. */
+#if defined(CONFIG_SYS_I2C)
+	void		*cur_i2c_bus;	/* current used i2c bus */
+#endif
 } gd_t;
 
 #include <asm-generic/global_data_flags.h>
diff --git a/arch/nios2/include/asm/global_data.h b/arch/nios2/include/asm/global_data.h
index 3b0d9e6..e4c36dc 100644
--- a/arch/nios2/include/asm/global_data.h
+++ b/arch/nios2/include/asm/global_data.h
@@ -42,6 +42,9 @@  typedef	struct	global_data {
 #endif
 	void		**jt;		/* Standalone app jump table */
 	char		env_buf[32];	/* buffer for getenv() before reloc. */
+#if defined(CONFIG_SYS_I2C)
+	void		*cur_i2c_bus;	/* current used i2c bus */
+#endif
 } gd_t;
 
 #include <asm-generic/global_data_flags.h>
diff --git a/arch/powerpc/include/asm/global_data.h b/arch/powerpc/include/asm/global_data.h
index 5a5877f..f063be9 100644
--- a/arch/powerpc/include/asm/global_data.h
+++ b/arch/powerpc/include/asm/global_data.h
@@ -182,6 +182,9 @@  typedef	struct	global_data {
 #endif
 	void		**jt;		/* jump table */
 	char		env_buf[32];	/* buffer for getenv() before reloc. */
+#if defined(CONFIG_SYS_I2C)
+	void		*cur_i2c_bus;	/* current used i2c bus */
+#endif
 } gd_t;
 
 #include <asm-generic/global_data_flags.h>
diff --git a/arch/sh/include/asm/global_data.h b/arch/sh/include/asm/global_data.h
index 6e534ad..1929352 100644
--- a/arch/sh/include/asm/global_data.h
+++ b/arch/sh/include/asm/global_data.h
@@ -42,6 +42,9 @@  typedef	struct global_data
 	unsigned long	env_valid;	/* Checksum of Environment valid */
 	void		**jt;		/* Standalone app jump table */
 	char		env_buf[32];	/* buffer for getenv() before reloc. */
+#if defined(CONFIG_SYS_I2C)
+	void		*cur_i2c_bus;	/* current used i2c bus */
+#endif
 } gd_t;
 
 #include <asm-generic/global_data_flags.h>
diff --git a/arch/sparc/include/asm/global_data.h b/arch/sparc/include/asm/global_data.h
index 93d3cc0..71432aa 100644
--- a/arch/sparc/include/asm/global_data.h
+++ b/arch/sparc/include/asm/global_data.h
@@ -74,6 +74,9 @@  typedef struct global_data {
 #endif
 	void	**jt;			/* jump table */
 	char	env_buf[32];		/* buffer for getenv() before reloc. */
+#if defined(CONFIG_SYS_I2C)
+	void		*cur_i2c_bus;	/* current used i2c bus */
+#endif
 } gd_t;
 
 #include <asm-generic/global_data_flags.h>
diff --git a/arch/x86/include/asm/global_data.h b/arch/x86/include/asm/global_data.h
index 6d29c0b..88e9d6c 100644
--- a/arch/x86/include/asm/global_data.h
+++ b/arch/x86/include/asm/global_data.h
@@ -57,6 +57,9 @@  typedef	struct global_data {
 	unsigned long	reset_status;	/* reset status register at boot */
 	void		**jt;		/* jump table */
 	char		env_buf[32];	/* buffer for getenv() before reloc. */
+#if defined(CONFIG_SYS_I2C)
+	void		*cur_i2c_bus;	/* current used i2c bus */
+#endif
 } gd_t;
 
 static inline gd_t *get_fs_gd_ptr(void)
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index 5dbdbe3..6373306 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -46,6 +46,7 @@  COBJS-$(CONFIG_TSI108_I2C) += tsi108_i2c.o
 COBJS-$(CONFIG_U8500_I2C) += u8500_i2c.o
 COBJS-$(CONFIG_SH_I2C) += sh_i2c.o
 COBJS-$(CONFIG_SH_SH7734_I2C) += sh_sh7734_i2c.o
+COBJS-$(CONFIG_SYS_I2C) += i2c_core.o
 
 COBJS	:= $(COBJS-y)
 SRCS	:= $(COBJS:.o=.c)
diff --git a/drivers/i2c/i2c_core.c b/drivers/i2c/i2c_core.c
new file mode 100644
index 0000000..cdb6a06
--- /dev/null
+++ b/drivers/i2c/i2c_core.c
@@ -0,0 +1,363 @@ 
+/*
+ * Copyright (C) 2009 Sergey Kubushyn <ksi@koi8.net>
+ *
+ * Multibus/multiadapter I2C core functions (wrappers)
+ */
+#include <common.h>
+#include <i2c.h>
+
+struct i2c_adapter *i2c_adap[CONFIG_SYS_NUM_I2C_ADAPTERS] =
+			CONFIG_SYS_I2C_ADAPTERS;
+
+struct i2c_bus_hose i2c_bus[CONFIG_SYS_NUM_I2C_BUSSES] =
+			CONFIG_SYS_I2C_BUSSES;
+
+DECLARE_GLOBAL_DATA_PTR;
+
+void i2c_reloc_fixup(void)
+{
+#if defined(CONFIG_NEEDS_MANUAL_RELOC)
+	int		i;
+	unsigned long	addr;
+
+	for (i = 0; i < CONFIG_SYS_NUM_I2C_ADAPTERS; i++) {
+		/* Adapter itself */
+		addr = (unsigned long)i2c_adap[i];
+		if (addr != 0)
+			addr += gd->reloc_off;
+
+		i2c_adap[i] = (struct i2c_adapter *)addr;
+		/* i2c_init() */
+		addr = (unsigned long)i2c_adap[i]->init;
+		if (addr != 0)
+			addr += gd->reloc_off;
+
+		i2c_adap[i]->init = (void (*)(int, int))addr;
+		/* i2c_probe() */
+		addr = (unsigned long)i2c_adap[i]->probe;
+		if (addr != 0)
+			addr += gd->reloc_off;
+
+		i2c_adap[i]->probe = (int (*)(uint8_t))addr;
+		/* i2c_read() */
+		addr = (unsigned long)i2c_adap[i]->read;
+		if (addr != 0)
+			addr += gd->reloc_off;
+
+		i2c_adap[i]->read = (int (*)(uint8_t, uint, int, uint8_t *,
+					int))addr;
+		/* i2c_write() */
+		addr = (unsigned long)i2c_adap[i]->write;
+		if (addr != 0)
+			addr += gd->reloc_off;
+
+		i2c_adap[i]->write = (int (*)(uint8_t, uint, int, uint8_t *,
+					int))addr;
+		/* i2c_set_bus_speed() */
+		addr = (unsigned long)i2c_adap[i]->set_bus_speed;
+		if (addr != 0)
+			addr += gd->reloc_off;
+
+		i2c_adap[i]->set_bus_speed = (uint (*)(uint))addr;
+		/* name */
+		addr = (unsigned long)i2c_adap[i]->name;
+		if (addr != 0)
+			addr += gd->reloc_off;
+
+		i2c_adap[i]->name = (char *)addr;
+	}
+	gd->cur_i2c_bus += gd->reloc_off;
+#else
+	/*
+	 * we need this here to set after relocation gd->cur_i2c_bus
+	 * to the new relocated value.
+	 */
+	gd->cur_i2c_bus = NULL;
+	i2c_set_bus_num(CONFIG_SYS_SPD_BUS_NUM);
+#endif
+}
+
+#ifndef CONFIG_SYS_I2C_DIRECT_BUS
+/*
+ * i2c_mux_set()
+ * -------------
+ *
+ * This turns on the given channel on I2C multiplexer chip connected to
+ * a given I2C adapter directly or via other multiplexers. In the latter
+ * case the entire multiplexer chain must be initialized first starting
+ * with the one connected directly to the adapter. When disabling a chain
+ * muxes must be programmed in reverse order, starting with the one
+ * farthest from the adapter.
+ *
+ * mux_id is the multiplexer chip type from defined in i2c.h. So far only
+ * NXP (Philips) PCA954x multiplexers are supported. Switches are NOT
+ * supported (anybody uses them?)
+ */
+
+static int i2c_mux_set(struct i2c_adapter *adap, int mux_id, int chip,
+			int channel)
+{
+	uint8_t	buf;
+
+	/* channel < 0 - turn off the mux */
+	if (channel < 0) {
+		buf = 0;
+		return adap->write(chip, 0, 0, &buf, 1);
+	}
+
+	switch (mux_id) {
+	case I2C_MUX_PCA9540_ID:
+	case I2C_MUX_PCA9542_ID:
+		if (channel > 1)
+			return -1;
+		buf = (uint8_t)((channel & 0x01) | (1 << 2));
+		break;
+	case I2C_MUX_PCA9544_ID:
+		if (channel > 3)
+			return -1;
+		buf = (uint8_t)((channel & 0x03) | (1 << 2));
+		break;
+	case I2C_MUX_PCA9547_ID:
+		if (channel > 7)
+			return -1;
+		buf = (uint8_t)((channel & 0x07) | (1 << 3));
+		break;
+	default:
+		return -1;
+	}
+
+	return adap->write(chip, 0, 0, &buf, 1);
+}
+#endif
+
+/*
+ * i2c_init_bus():
+ * ---------------
+ *
+ * Initializes one bus. Will initialize the parent adapter. No current bus
+ * changes, no mux (if any) setup.
+ */
+static void i2c_init_bus(unsigned int bus_no, int speed, int slaveaddr)
+{
+	if (bus_no >= CONFIG_SYS_NUM_I2C_BUSSES)
+		return;
+
+	I2C_ADAP->init(speed, slaveaddr);
+
+	if (gd->flags & GD_FLG_RELOC) {
+		I2C_ADAP->init_done = 1;
+		I2C_ADAP->speed = speed;
+		I2C_ADAP->slaveaddr = slaveaddr;
+	}
+}
+
+/*
+ * i2c_init_all():
+ *
+ * not longer needed, will deleted. Actual init the SPD_BUS
+ * for compatibility.
+ * i2c_adap[] must be initialized beforehead with function pointers and
+ * data, including speed and slaveaddr.
+ */
+void i2c_init_all(void)
+{
+	i2c_set_bus_num(CONFIG_SYS_SPD_BUS_NUM);
+	return;
+}
+
+/*
+ * i2c_get_bus_num():
+ * ------------------
+ *
+ *  Returns index of currently active I2C bus.  Zero-based.
+ */
+unsigned int i2c_get_bus_num(void)
+{
+	int i = 0;
+
+	if (gd->cur_i2c_bus == NULL)
+		return CONFIG_SYS_SPD_BUS_NUM;
+
+	while (i < CONFIG_SYS_NUM_I2C_BUSSES) {
+		if (I2C_BUS == &i2c_bus[i])
+			return i;
+		i++;
+	}
+
+	return CONFIG_SYS_SPD_BUS_NUM;
+}
+
+/*
+ * i2c_set_bus_num():
+ * ------------------
+ *
+ *  Change the active I2C bus. Subsequent read/write calls will
+ *  go to this one. Sets all of the muxes in a proper condition
+ *  if that bus is behind muxes.
+ *  If previously selected bus is behind the muxes turns off all the
+ *  muxes along the path to that bus.
+ *
+ *	bus - bus index, zero based
+ *
+ *	Returns: 0 on success, not 0 on failure
+ */
+int i2c_set_bus_num(unsigned int bus)
+{
+#ifndef CONFIG_SYS_I2C_DIRECT_BUS
+	int		i;
+	uint8_t	buf;
+#endif
+
+	if (bus >= CONFIG_SYS_NUM_I2C_BUSSES)
+		return -1;
+
+	if (gd->cur_i2c_bus == NULL)
+		gd->cur_i2c_bus = &i2c_bus[bus];
+	else if ((&i2c_bus[bus] == I2C_BUS) &&
+		(I2C_ADAP->init_done > 0))
+		return 0;
+#ifndef CONFIG_SYS_I2C_DIRECT_BUS
+	else {
+		/* Disconnect current bus (turn off muxes if any) */
+		if ((I2C_BUS->next_hop[0].chip != 0) &&
+		    (I2C_ADAP->init_done != 0)) {
+			i = CONFIG_SYS_I2C_MAX_HOPS;
+			do {
+				uint8_t	chip;
+
+				chip = I2C_BUS->next_hop[--i].chip;
+				if (chip == 0)
+					continue;
+
+				I2C_ADAP->write(chip, 0, 0, &buf, 1);
+			} while (i > 0);
+		}
+	}
+#endif
+
+	gd->cur_i2c_bus = &i2c_bus[bus];
+	if (I2C_ADAP->init_done == 0)
+		i2c_init_bus(bus, I2C_ADAP->speed, I2C_ADAP->slaveaddr);
+
+#ifndef CONFIG_SYS_I2C_DIRECT_BUS
+	/* Connect requested bus if behind muxes */
+	if (I2C_BUS->next_hop[0].chip != 0) {
+
+		/* Set all muxes along the path to that bus */
+		for (i = 0; i < CONFIG_SYS_I2C_MAX_HOPS; i++) {
+			int	ret;
+
+			if (I2C_BUS->next_hop[i].chip == 0)
+				break;
+
+			ret = i2c_mux_set(I2C_ADAP,
+					I2C_BUS->next_hop[i].mux.id,
+					I2C_BUS->next_hop[i].chip,
+					I2C_BUS->next_hop[i].channel);
+			if (ret != 0) {
+				printf("%s: could not set mux: id: %d "\
+					"chip: %x channel: %d\n", __func__,
+					I2C_BUS->next_hop[i].mux.id,
+					I2C_BUS->next_hop[i].chip,
+					I2C_BUS->next_hop[i].channel);
+			}
+		}
+	}
+#endif
+
+	return 0;
+}
+
+/*
+ * Probe the given I2C chip address.  Returns 0 if a chip responded,
+ * not 0 on failure.
+ */
+int i2c_probe(uint8_t chip)
+{
+	return I2C_ADAP->probe(chip);
+}
+
+/*
+ * Read/Write interface:
+ *   chip:    I2C chip address, range 0..127
+ *   addr:    Memory (register) address within the chip
+ *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
+ *              memories, 0 for register type devices with only one
+ *              register)
+ *   buffer:  Where to read/write the data
+ *   len:     How many bytes to read/write
+ *
+ *   Returns: 0 on success, not 0 on failure
+ */
+int i2c_read(uint8_t chip, unsigned int addr, int alen,
+				uint8_t *buffer, int len)
+{
+	return I2C_ADAP->read(chip, addr, alen, buffer, len);
+}
+
+int i2c_write(uint8_t chip, unsigned int addr, int alen,
+				uint8_t *buffer, int len)
+{
+	return I2C_ADAP->write(chip, addr, alen, buffer, len);
+}
+
+unsigned int i2c_set_bus_speed(unsigned int speed)
+{
+	unsigned int ret;
+
+	if (I2C_ADAP->set_bus_speed == NULL)
+		return 0;
+	ret = I2C_ADAP->set_bus_speed(speed);
+	if (gd->flags & GD_FLG_RELOC)
+		I2C_ADAP->speed = ret;
+
+	return ret;
+}
+
+unsigned int i2c_get_bus_speed(void)
+{
+	struct i2c_adapter *cur = I2C_ADAP;
+	return cur->speed;
+}
+
+uint8_t i2c_reg_read(uint8_t addr, uint8_t reg)
+{
+	uint8_t buf;
+
+#ifdef CONFIG_8xx
+	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
+	/* maybe it is now the time for it ... */
+	i2c_set_bus_num(i2c_get_bus_num());
+#endif
+	i2c_read(addr, reg, 1, &buf, 1);
+
+#ifdef DEBUG
+	printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x\n",
+		 __func__, i2c_get_bus_num(), addr, reg, buf);
+#endif
+
+	return buf;
+}
+
+void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val)
+{
+#ifdef CONFIG_8xx
+	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
+	/* maybe it is now the time for it ... */
+	i2c_set_bus_num(i2c_get_bus_num());
+#endif
+
+#ifdef DEBUG
+	printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x\n",
+	       __func__, i2c_get_bus_num(), addr, reg, val);
+#endif
+
+	i2c_write(addr, reg, 1, &val, 1);
+}
+
+void __i2c_init(int speed, int slaveaddr)
+{
+	i2c_init_bus(i2c_get_bus_num(), speed, slaveaddr);
+}
+void i2c_init(int speed, int slaveaddr)
+	__attribute__((weak, alias("__i2c_init")));
diff --git a/include/i2c.h b/include/i2c.h
index 16f099d..44a05cd 100644
--- a/include/i2c.h
+++ b/include/i2c.h
@@ -1,4 +1,8 @@ 
 /*
+ * Copyright (C) 2009 Sergey Kubushyn <ksi@koi8.net>
+ * Copyright (C) 2009 Heiko Schocher <hs@denx.de>
+ * Changes for multibus/multiadapter I2C support.
+ *
  * (C) Copyright 2001
  * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
  *
@@ -46,16 +50,25 @@ 
  */
 #define I2C_RXTX_LEN	128	/* maximum tx/rx buffer length */
 
-#ifdef	CONFIG_I2C_MULTI_BUS
-#define	MAX_I2C_BUS			2
-#define	I2C_MULTI_BUS			1
-#else
-#define	MAX_I2C_BUS			1
-#define	I2C_MULTI_BUS			0
+#ifndef CONFIG_SYS_NUM_I2C_ADAPTERS
+#define CONFIG_SYS_NUM_I2C_ADAPTERS	1
 #endif
 
-#if !defined(CONFIG_SYS_MAX_I2C_BUS)
-#define CONFIG_SYS_MAX_I2C_BUS		MAX_I2C_BUS
+#if !defined(CONFIG_SYS_I2C_MAX_HOPS)
+#define CONFIG_SYS_I2C_DIRECT_BUS	1
+#define CONFIG_SYS_I2C_MAX_HOPS		1
+#if !defined(CONFIG_SYS_NUM_I2C_BUSSES)
+#define CONFIG_SYS_NUM_I2C_BUSSES	CONFIG_SYS_NUM_I2C_ADAPTERS
+#define CONFIG_SYS_I2C_BUSSES { {0, {I2C_NULL_HOP} } }
+#endif
+#else
+#undef CONFIG_SYS_I2C_DIRECT_BUS
+#ifndef CONFIG_SYS_NUM_I2C_BUSSES
+#define CONFIG_SYS_NUM_I2C_BUSSES	1
+#endif
+#ifndef CONFIG_SYS_I2C_BUSSES
+#define CONFIG_SYS_I2C_BUSSES { {0, {I2C_NULL_HOP} } }
+#endif
 #endif
 
 /* define the I2C bus number for RTC and DTT if not already done */
@@ -69,6 +82,59 @@ 
 #define CONFIG_SYS_SPD_BUS_NUM		0
 #endif
 
+struct i2c_adapter {
+	void		(*init)(int speed, int slaveaddr);
+	int		(*probe)(uint8_t chip);
+	int		(*read)(uint8_t chip, uint addr, int alen,
+				uint8_t *buffer, int len);
+	int		(*write)(uint8_t chip, uint addr, int alen,
+				uint8_t *buffer, int len);
+	uint		(*set_bus_speed)(uint speed);
+
+	int		speed;
+	int		slaveaddr;
+	int		init_done;
+	int		hwadapnr;
+	char		*name;
+};
+
+struct i2c_mux {
+	int	id;
+	char	name[16];
+};
+
+struct i2c_next_hop {
+	struct i2c_mux		mux;
+	uint8_t		chip;
+	uint8_t		channel;
+};
+
+struct i2c_bus_hose {
+	int	adapter;
+	struct i2c_next_hop	next_hop[CONFIG_SYS_I2C_MAX_HOPS];
+};
+
+#define I2C_NULL_HOP	{{-1, ""}, 0, 0}
+
+extern struct i2c_bus_hose	i2c_bus[];
+extern struct i2c_adapter	*i2c_adap[];
+
+#define	I2C_ADAP_NR(bus)	i2c_adap[i2c_bus[bus].adapter]
+#define	I2C_BUS			((struct i2c_bus_hose *)gd->cur_i2c_bus)
+#define	I2C_ADAP		i2c_adap[I2C_BUS->adapter]
+#define I2C_ADAP_HWNR		(I2C_ADAP->hwadapnr)
+
+#ifndef CONFIG_SYS_I2C_DIRECT_BUS
+#define I2C_MUX_PCA9540_ID	1
+#define I2C_MUX_PCA9540		{I2C_MUX_PCA9540_ID, "PCA9540B"}
+#define I2C_MUX_PCA9542_ID	2
+#define I2C_MUX_PCA9542		{I2C_MUX_PCA9542_ID, "PCA9542A"}
+#define I2C_MUX_PCA9544_ID	3
+#define I2C_MUX_PCA9544		{I2C_MUX_PCA9544_ID, "PCA9544A"}
+#define I2C_MUX_PCA9547_ID	4
+#define I2C_MUX_PCA9547		{I2C_MUX_PCA9547_ID, "PCA9547A"}
+#endif
+
 #ifndef I2C_SOFT_DECLARATIONS
 # if defined(CONFIG_MPC8260)
 #  define I2C_SOFT_DECLARATIONS volatile ioport_t *iop = ioport_addr((immap_t *)CONFIG_SYS_IMMR, I2C_PORT);
@@ -134,6 +200,104 @@  int i2x_mux_select_mux(int bus);
 int i2c_mux_ident_muxstring_f (uchar *buf);
 #endif
 
+#ifdef CONFIG_SYS_I2C
+/*
+ * Initialization, must be called once on start up, may be called
+ * repeatedly to change the speed and slave addresses.
+ */
+void i2c_init(unsigned int speed, int slaveaddr);
+#ifdef CONFIG_SYS_I2C_INIT_BOARD
+void i2c_init_board(void);
+#endif
+
+/*
+ * i2c_get_bus_num:
+ *
+ *  Returns index of currently active I2C bus.  Zero-based.
+ */
+unsigned int i2c_get_bus_num(void);
+
+/*
+ * i2c_set_bus_num:
+ *
+ *  Change the active I2C bus.  Subsequent read/write calls will
+ *  go to this one.
+ *
+ *	bus - bus index, zero based
+ *
+ *	Returns: 0 on success, not 0 on failure
+ *
+ */
+int i2c_set_bus_num(unsigned int bus);
+
+/*
+ * i2c_init_all():
+ *
+ * Initializes all I2C adapters in the system. All i2c_adap structures must
+ * be initialized beforehead with function pointers and data, including
+ * speed and slaveaddr. Returns 0 on success, non-0 on failure.
+ */
+void i2c_init_all(void);
+
+/*
+ * Probe the given I2C chip address.  Returns 0 if a chip responded,
+ * not 0 on failure.
+ */
+int i2c_probe(uint8_t chip);
+
+/*
+ * Read/Write interface:
+ *   chip:    I2C chip address, range 0..127
+ *   addr:    Memory (register) address within the chip
+ *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
+ *              memories, 0 for register type devices with only one
+ *              register)
+ *   buffer:  Where to read/write the data
+ *   len:     How many bytes to read/write
+ *
+ *   Returns: 0 on success, not 0 on failure
+ */
+int i2c_read(uint8_t chip, unsigned int addr, int alen,
+				uint8_t *buffer, int len);
+
+int i2c_write(uint8_t chip, unsigned int addr, int alen,
+				uint8_t *buffer, int len);
+
+/*
+ * Utility routines to read/write registers.
+ */
+uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
+
+void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
+
+/*
+ * i2c_set_bus_speed:
+ *
+ *  Change the speed of the active I2C bus
+ *
+ *	speed - bus speed in Hz
+ *
+ *	Returns: new bus speed
+ *
+ */
+unsigned int i2c_set_bus_speed(unsigned int speed);
+
+/*
+ * i2c_get_bus_speed:
+ *
+ *  Returns speed of currently active I2C bus in Hz
+ */
+
+unsigned int i2c_get_bus_speed(void);
+
+/*
+ * i2c_reloc_fixup:
+ *
+ * Adjusts I2C pointers after U-Boot is relocated to DRAM
+ */
+void i2c_reloc_fixup(void);
+#else
+
 /*
  * Probe the given I2C chip address.  Returns 0 if a chip responded,
  * not 0 on failure.
@@ -235,6 +399,22 @@  int i2c_set_bus_speed(unsigned int);
  */
 
 unsigned int i2c_get_bus_speed(void);
+#endif /* CONFIG_SYS_I2C */
+
+/*
+ * only for backwardcompatibility, should go away if we switched
+ * completely to new multibus support.
+ */
+#if (CONFIG_SYS_NUM_I2C_BUSSES > 1) || defined(CONFIG_I2C_MULTI_BUS)
+# if !defined(CONFIG_SYS_MAX_I2C_BUS)
+#  define CONFIG_SYS_MAX_I2C_BUS		2
+# endif
+# define I2C_MULTI_BUS				0
+#else
+# define CONFIG_SYS_MAX_I2C_BUS		1
+# define I2C_MULTI_BUS				0
+#endif
+
 
 /* NOTE: These two functions MUST be always_inline to avoid code growth! */
 static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline));