import i2c header from u-boot

This just imports a header. We may wish to modify the i2c interface
and/or unify it with the smbus interface we currently have.

Change-Id: I314f3aef62be936456c6c3e164a3db2c473b8792
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/2079
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

1 files changed, 279 insertions, 0 deletions

diff --git a/src/include/device/i2c.h b/src/include/device/i2c.h
new file mode 100644
index 0000000000..f1275e38af
--- /dev/null
+++ b/src/include/device/i2c.h
@@ -0,0 +1,279 @@
+/*
+ * (C) Copyright 2001
+ * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ * The original I2C interface was
+ *   (C) 2000 by Paolo Scaffardi (arsenio@tin.it)
+ *   AIRVENT SAM s.p.a - RIMINI(ITALY)
+ * but has been changed substantially.
+ */
+
+#ifndef _I2C_H_
+#define _I2C_H_
+
+/*
+ * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
+ *
+ * The implementation MUST NOT use static or global variables if the
+ * I2C routines are used to read SDRAM configuration information
+ * because this is done before the memories are initialized. Limited
+ * use of stack-based variables are OK (the initial stack size is
+ * limited).
+ *
+ * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
+ */
+
+/*
+ * Configuration items.
+ */
+#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
+#endif
+
+#if !defined(CONFIG_SYS_MAX_I2C_BUS)
+#define CONFIG_SYS_MAX_I2C_BUS		MAX_I2C_BUS
+#endif
+
+/* define the I2C bus number for RTC and DTT if not already done */
+#if !defined(CONFIG_SYS_RTC_BUS_NUM)
+#define CONFIG_SYS_RTC_BUS_NUM		0
+#endif
+#if !defined(CONFIG_SYS_DTT_BUS_NUM)
+#define CONFIG_SYS_DTT_BUS_NUM		0
+#endif
+#if !defined(CONFIG_SYS_SPD_BUS_NUM)
+#define CONFIG_SYS_SPD_BUS_NUM		0
+#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);
+# elif defined(CONFIG_8xx)
+#  define I2C_SOFT_DECLARATIONS	volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
+
+# elif (defined(CONFIG_AT91RM9200) || \
+	defined(CONFIG_AT91SAM9260) ||  defined(CONFIG_AT91SAM9261) || \
+	defined(CONFIG_AT91SAM9263)) && !defined(CONFIG_AT91_LEGACY)
+#  define I2C_SOFT_DECLARATIONS	at91_pio_t *pio	= (at91_pio_t *) ATMEL_BASE_PIOA;
+# else
+#  define I2C_SOFT_DECLARATIONS
+# endif
+#endif
+
+#ifdef CONFIG_8xx
+/* Set default value for the I2C bus speed on 8xx. In the
+ * future, we'll define these in all 8xx board config files.
+ */
+#ifndef	CONFIG_SYS_I2C_SPEED
+#define	CONFIG_SYS_I2C_SPEED	50000
+#endif
+#endif
+
+/*
+ * Many boards/controllers/drivers don't support an I2C slave interface so
+ * provide a default slave address for them for use in common code.  A real
+ * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does
+ * support a slave interface.
+ */
+#ifndef	CONFIG_SYS_I2C_SLAVE
+#define	CONFIG_SYS_I2C_SLAVE	0xfe
+#endif
+
+/*
+ * Initialization, must be called once on start up, may be called
+ * repeatedly to change the speed and slave addresses.
+ */
+void i2c_init(int speed, int slaveaddr);
+void i2c_init_board(void);
+#ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT
+void i2c_board_late_init(void);
+#endif
+
+#if defined(CONFIG_I2C_MUX)
+
+typedef struct _mux {
+	uchar	chip;
+	uchar	channel;
+	char	*name;
+	struct _mux	*next;
+} I2C_MUX;
+
+typedef struct _mux_device {
+	int	busid;
+	I2C_MUX	*mux;	/* List of muxes, to reach the device */
+	struct _mux_device	*next;
+} I2C_MUX_DEVICE;
+
+I2C_MUX_DEVICE	*i2c_mux_search_device(int id);
+I2C_MUX_DEVICE *i2c_mux_ident_muxstring (uchar *buf);
+int i2x_mux_select_mux(int bus);
+int i2c_mux_ident_muxstring_f (uchar *buf);
+#endif
+
+/*
+ * Probe the given I2C chip address.  Returns 0 if a chip responded,
+ * not 0 on failure.
+ */
+int i2c_probe(uchar 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(uchar chip, uint addr, int alen, uchar *buffer, int len);
+int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
+
+/*
+ * Utility routines to read/write registers.
+ */
+static inline u8 i2c_reg_read(u8 addr, u8 reg)
+{
+	u8 buf;
+
+#ifdef CONFIG_8xx
+	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
+	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
+#endif
+
+#ifdef DEBUG
+	printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg);
+#endif
+
+	i2c_read(addr, reg, 1, &buf, 1);
+
+	return buf;
+}
+
+static inline void i2c_reg_write(u8 addr, u8 reg, u8 val)
+{
+#ifdef CONFIG_8xx
+	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
+	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
+#endif
+
+#ifdef DEBUG
+	printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n",
+	       __func__, addr, reg, val);
+#endif
+
+	i2c_write(addr, reg, 1, &val, 1);
+}
+
+/*
+ * Functions for setting the current I2C bus and its speed
+ */
+
+/*
+ * 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_get_bus_num:
+ *
+ *  Returns index of currently active I2C bus.  Zero-based.
+ */
+
+unsigned int i2c_get_bus_num(void);
+
+/*
+ * i2c_set_bus_speed:
+ *
+ *  Change the speed of the active I2C bus
+ *
+ *	speed - bus speed in Hz
+ *
+ *	Returns: 0 on success, not 0 on failure
+ *
+ */
+int i2c_set_bus_speed(unsigned int);
+
+/*
+ * i2c_get_bus_speed:
+ *
+ *  Returns speed of currently active I2C bus in Hz
+ */
+
+unsigned int i2c_get_bus_speed(void);
+
+/* NOTE: These two functions MUST be always_inline to avoid code growth! */
+static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline));
+static inline unsigned int I2C_GET_BUS(void)
+{
+	return I2C_MULTI_BUS ? i2c_get_bus_num() : 0;
+}
+
+static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline));
+static inline void I2C_SET_BUS(unsigned int bus)
+{
+	if (I2C_MULTI_BUS)
+		i2c_set_bus_num(bus);
+}
+
+/*
+ * Set an early register base for a given i2c peripheral.
+ * This is used to access a single i2c bus early on in the boot sequence.
+ *
+ * @param base:	The base address of the i2c peripheral's register map
+ */
+void i2c_set_early_reg(unsigned int base);
+
+/**
+ * Find the I2C bus number by given a FDT I2C node.
+ *
+ * @param blob	Device tree blbo
+ * @param node	FDT I2C node to find
+ * @return the number of I2C bus (zero based), or -1 on error
+ */
+int i2c_get_bus_num_fdt(const void *blob, int node);
+
+/**
+ * Reset the I2C bus represented by the given a FDT I2C node.
+ *
+ * @param blob	Device tree blbo
+ * @param node	FDT I2C node to find
+ * @return 0 if port was reset, -1 if not found
+ */
+int i2c_reset_port_fdt(const void *blob, int node);
+
+#endif	/* _I2C_H_ */