[U-Boot] [PATCH v3 1/9] i2c: add i2c_core and prepare for new multibus support
Heiko Schocher
hs at denx.de
Sat May 4 14:01:35 CEST 2013
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 at denx.de>
Signed-off-by: Simon Glass <sjg at chromium.org>
Cc: Mike Frysinger <vapier at gentoo.org>
Cc: Stephen Warren <swarren at wwwdotorg.org>
---
- changes against Simons patches
(see: http://www.mail-archive.com/u-boot@lists.denx.de/msg75530.html):
- 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
- changes for v2:
- rebase against current mainline 178d0cc1a4c73c3341afbeb2a93b172de8c96bd1
- pass i2c_adapter struct to i2c_core callbacks
suggested by Stephen Warren and Simon Glass.
- add i2c_init_board() to i2c_init_all() as Simon found
in his tests.
- need CONFIG_SYS_I2C_BUSES only, if i2c muxes used
(Steven Warren suggested to get rid of this completely, now
we need this defines in a first step only in the case, we have
i2c muxes)
- global data is now a int only
- move i2c_init_board() to drivers/i2c/i2c_core.c
- add correct license text to i2c_core.c
- changes for v3:
- introduce U_BOOT_I2C_ADAP_COMPLETE for adding an i2c adapter.
Compiler collects the used i2c adapters in _u_boot_list_i2c,
so no need for defining the used i2c adpaters in the board config file.
-> drop CONFIG_SYS_NUM_I2C_ADAPTERS and CONFIG_SYS_I2C_ADAPTERS
---
drivers/i2c/Makefile | 1 +
drivers/i2c/i2c_core.c | 414 ++++++++++++++++++++++++++++++++++++++
include/asm-generic/global_data.h | 3 +
include/i2c.h | 215 +++++++++++++++++++-
4 Dateien geändert, 624 Zeilen hinzugefügt(+), 9 Zeilen entfernt(-)
create mode 100644 drivers/i2c/i2c_core.c
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..3c01893
--- /dev/null
+++ b/drivers/i2c/i2c_core.c
@@ -0,0 +1,414 @@
+/*
+ * Copyright (C) 2009 Sergey Kubushyn <ksi at koi8.net>
+ *
+ * (C) Copyright 2012
+ * Heiko Schocher, DENX Software Engineering, hs at denx.de.
+ *
+ * Multibus/multiadapter I2C core functions (wrappers)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <common.h>
+#include <i2c.h>
+
+struct i2c_adapter *i2c_get_adapter(int index)
+{
+ struct i2c_adapter *i2c_adap_p = ll_entry_start(struct i2c_adapter,
+ i2c);
+ int max = ll_entry_count(struct i2c_adapter, i2c);
+ int i;
+
+ if (index >= max) {
+ printf("Error, wrong i2c adapter %d max %d possible\n",
+ index, max);
+ return i2c_adap_p;
+ }
+ if (index == 0)
+ return i2c_adap_p;
+
+ for (i = 0; i < index; i++)
+ i2c_adap_p++;
+
+ return i2c_adap_p;
+}
+
+#if !defined(CONFIG_SYS_I2C_DIRECT_BUS)
+struct i2c_bus_hose i2c_bus[CONFIG_SYS_NUM_I2C_BUSES] =
+ CONFIG_SYS_I2C_BUSES;
+#endif
+
+DECLARE_GLOBAL_DATA_PTR;
+
+void i2c_reloc_fixup(void)
+{
+#if defined(CONFIG_NEEDS_MANUAL_RELOC)
+ struct i2c_adapter *i2c_adap_p = ll_entry_start(struct i2c_adapter,
+ i2c);
+ struct i2c_adapter *tmp = i2c_adap_p;
+ int max = ll_entry_count(struct i2c_adapter, i2c);
+ int i;
+ unsigned long addr;
+
+ if (gd->reloc_off == 0)
+ return;
+
+ for (i = 0; i < max; i++) {
+ /* adapter itself */
+ addr = (unsigned long)i2c_adap_p;
+ addr += gd->reloc_off;
+ i2c_adap_p = (struct i2c_adapter *)addr;
+ /* i2c_init() */
+ addr = (unsigned long)i2c_adap_p->init;
+ addr += gd->reloc_off;
+ i2c_adap_p->init = (void (*)(int, int))addr;
+ /* i2c_probe() */
+ addr = (unsigned long)i2c_adap_p->probe;
+ addr += gd->reloc_off;
+ i2c_adap_p->probe = (int (*)(uint8_t))addr;
+ /* i2c_read() */
+ addr = (unsigned long)i2c_adap_p->read;
+ addr += gd->reloc_off;
+ i2c_adap_p->read = (int (*)(uint8_t, uint, int, uint8_t *,
+ int))addr;
+ /* i2c_write() */
+ addr = (unsigned long)i2c_adap_p->write;
+ addr += gd->reloc_off;
+ i2c_adap_p->write = (int (*)(uint8_t, uint, int, uint8_t *,
+ int))addr;
+ /* i2c_set_bus_speed() */
+ addr = (unsigned long)i2c_adap_p->set_bus_speed;
+ addr += gd->reloc_off;
+ i2c_adap_p->set_bus_speed = (uint (*)(uint))addr;
+ /* name */
+ addr = (unsigned long)i2c_adap_p->name;
+ addr += gd->reloc_off;
+ i2c_adap_p->name = (char *)addr;
+ tmp++;
+ i2c_adap_p = tmp;
+ }
+#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;
+ int ret;
+
+ /* channel < 0 - turn off the mux */
+ if (channel < 0) {
+ buf = 0;
+ ret = adap->write(adap, chip, 0, 0, &buf, 1);
+ if (ret)
+ printf("%s: Could not turn off the mux.\n", __func__);
+ return ret;
+ }
+
+ 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:
+ printf("%s: wrong mux id: %d\n", __func__, mux_id);
+ return -1;
+ }
+
+ ret = adap->write(adap, chip, 0, 0, &buf, 1);
+ if (ret)
+ printf("%s: could not set mux: id: %d chip: %x channel: %d\n",
+ __func__, mux_id, chip, channel);
+ return ret;
+}
+
+static int i2c_mux_set_all(void)
+{
+ struct i2c_bus_hose *i2c_bus_tmp = &i2c_bus[I2C_BUS];
+ int i;
+
+ /* Connect requested bus if behind muxes */
+ if (i2c_bus_tmp->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_tmp->next_hop[i].chip == 0)
+ break;
+
+ ret = i2c_mux_set(I2C_ADAP,
+ i2c_bus_tmp->next_hop[i].mux.id,
+ i2c_bus_tmp->next_hop[i].chip,
+ i2c_bus_tmp->next_hop[i].channel);
+ if (ret != 0)
+ return ret;
+ }
+ }
+ return 0;
+}
+
+static int i2c_mux_disconnet_all(void)
+{
+ struct i2c_bus_hose *i2c_bus_tmp = &i2c_bus[I2C_BUS];
+ int i;
+ uint8_t buf;
+
+ if (I2C_ADAP->init_done == 0)
+ return 0;
+
+ /* Disconnect current bus (turn off muxes if any) */
+ if ((i2c_bus_tmp->next_hop[0].chip != 0) &&
+ (I2C_ADAP->init_done != 0)) {
+ i = CONFIG_SYS_I2C_MAX_HOPS;
+ do {
+ uint8_t chip;
+ int ret;
+
+ chip = i2c_bus_tmp->next_hop[--i].chip;
+ if (chip == 0)
+ continue;
+
+ ret = I2C_ADAP->write(I2C_ADAP, chip, 0, 0, &buf, 1);
+ if (ret != 0) {
+ printf("i2c: mux diconnect error\n");
+ return ret;
+ }
+ } while (i > 0);
+ }
+
+ return 0;
+}
+#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_BUSES)
+ return;
+
+ I2C_ADAP->init(I2C_ADAP, speed, slaveaddr);
+
+ if (gd->flags & GD_FLG_RELOC) {
+ I2C_ADAP->init_done = 1;
+ I2C_ADAP->speed = speed;
+ I2C_ADAP->slaveaddr = slaveaddr;
+ }
+}
+
+/* implement possible board specific board init */
+static void __def_i2c_init_board(void)
+{
+}
+void i2c_init_board(void)
+ __attribute__((weak, alias("__def_i2c_init_board")));
+
+/*
+ * 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_init_board();
+ 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)
+{
+ return gd->cur_i2c_bus;
+}
+
+/*
+ * 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)
+{
+ int max = ll_entry_count(struct i2c_adapter, i2c);
+
+ if (I2C_ADAPTER(bus) >= max) {
+ printf("Error, wrong i2c adapter %d max %d possible\n",
+ I2C_ADAPTER(bus), max);
+ return -2;
+ }
+#ifndef CONFIG_SYS_I2C_DIRECT_BUS
+ if (bus >= CONFIG_SYS_NUM_I2C_BUSES)
+ return -1;
+#endif
+
+ if ((bus == I2C_BUS) && (I2C_ADAP->init_done > 0))
+ return 0;
+
+#ifndef CONFIG_SYS_I2C_DIRECT_BUS
+ i2c_mux_disconnet_all();
+#endif
+
+ gd->cur_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
+ i2c_mux_set_all();
+#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(I2C_ADAP, 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(I2C_ADAP, 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(I2C_ADAP, 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(I2C_ADAP, 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/asm-generic/global_data.h b/include/asm-generic/global_data.h
index 5416f46..c3919cc 100644
--- a/include/asm-generic/global_data.h
+++ b/include/asm-generic/global_data.h
@@ -85,6 +85,9 @@ typedef struct global_data {
unsigned long fdt_size; /* Space reserved for relocated FDT */
void **jt; /* jump table */
char env_buf[32]; /* buffer for getenv() before reloc. */
+#if defined(CONFIG_SYS_I2C)
+ int cur_i2c_bus; /* current used i2c bus */
+#endif
struct arch_global_data arch; /* architecture-specific data */
} gd_t;
#endif
diff --git a/include/i2c.h b/include/i2c.h
index c60d075..457fd7d 100644
--- a/include/i2c.h
+++ b/include/i2c.h
@@ -1,4 +1,8 @@
/*
+ * Copyright (C) 2009 Sergey Kubushyn <ksi at koi8.net>
+ * Copyright (C) 2009 - 2013 Heiko Schocher <hs at denx.de>
+ * Changes for multibus/multiadapter I2C support.
+ *
* (C) Copyright 2001
* Gerald Van Baren, Custom IDEAS, vanbaren at cideas.com.
*
@@ -46,16 +50,14 @@
*/
#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
+#if !defined(CONFIG_SYS_I2C_MAX_HOPS)
+/* no muxes used bus = i2c adapters */
+#define CONFIG_SYS_I2C_DIRECT_BUS 1
+#define CONFIG_SYS_I2C_MAX_HOPS 0
+#define CONFIG_SYS_NUM_I2C_BUSES ll_entry_count(struct i2c_adapter, i2c)
#else
-#define MAX_I2C_BUS 1
-#define I2C_MULTI_BUS 0
-#endif
-
-#if !defined(CONFIG_SYS_MAX_I2C_BUS)
-#define CONFIG_SYS_MAX_I2C_BUS MAX_I2C_BUS
+/* we use i2c muxes */
+#undef CONFIG_SYS_I2C_DIRECT_BUS
#endif
/* define the I2C bus number for RTC and DTT if not already done */
@@ -69,6 +71,88 @@
#define CONFIG_SYS_SPD_BUS_NUM 0
#endif
+struct i2c_adapter {
+ void (*init)(struct i2c_adapter *adap, int speed,
+ int slaveaddr);
+ int (*probe)(struct i2c_adapter *adap, uint8_t chip);
+ int (*read)(struct i2c_adapter *adap, uint8_t chip,
+ uint addr, int alen, uint8_t *buffer,
+ int len);
+ int (*write)(struct i2c_adapter *adap, uint8_t chip,
+ uint addr, int alen, uint8_t *buffer,
+ int len);
+ uint (*set_bus_speed)(struct i2c_adapter *adap,
+ uint speed);
+ int speed;
+ int slaveaddr;
+ int init_done;
+ int hwadapnr;
+ char *name;
+};
+
+#define U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
+ _set_speed, _speed, _slaveaddr, _hwadapnr, _name) \
+ { \
+ .init = _init, \
+ .probe = _probe, \
+ .read = _read, \
+ .write = _write, \
+ .set_bus_speed = _set_speed, \
+ .speed = _speed, \
+ .slaveaddr = _slaveaddr, \
+ .init_done = 0, \
+ .hwadapnr = _hwadapnr, \
+ .name = #_name \
+};
+
+#define U_BOOT_I2C_ADAP_COMPLETE(_name, _init, _probe, _read, _write, \
+ _set_speed, _speed, _slaveaddr, _hwadapnr) \
+ ll_entry_declare(struct i2c_adapter, _name, i2c) = \
+ U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
+ _set_speed, _speed, _slaveaddr, _hwadapnr, _name);
+
+struct i2c_adapter *i2c_get_adapter(int index);
+
+#ifndef CONFIG_SYS_I2C_DIRECT_BUS
+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[];
+
+#define I2C_ADAPTER(bus) i2c_bus[bus].adapter
+#else
+#define I2C_ADAPTER(bus) bus
+#endif
+#define I2C_BUS gd->cur_i2c_bus
+
+#define I2C_ADAP_NR(bus) i2c_get_adapter(I2C_ADAPTER(bus))
+#define I2C_ADAP I2C_ADAP_NR(gd->cur_i2c_bus)
+#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 +218,104 @@ 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 +417,21 @@ 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 defined(CONFIG_SYS_I2C) || 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));
--
1.7.11.7
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