3 * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
5 * See file CREDITS for list of people who contributed to this
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of
11 * the License, or (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
23 * The original I2C interface was
24 * (C) 2000 by Paolo Scaffardi (arsenio@tin.it)
25 * AIRVENT SAM s.p.a - RIMINI(ITALY)
26 * but has been changed substantially.
33 * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
35 * The implementation MUST NOT use static or global variables if the
36 * I2C routines are used to read SDRAM configuration information
37 * because this is done before the memories are initialized. Limited
38 * use of stack-based variables are OK (the initial stack size is
41 * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
45 * Configuration items.
47 #define I2C_RXTX_LEN 128 /* maximum tx/rx buffer length */
49 #if defined(CONFIG_I2C_MULTI_BUS)
50 #define CONFIG_SYS_MAX_I2C_BUS 2
51 #define I2C_GET_BUS() i2c_get_bus_num()
52 #define I2C_SET_BUS(a) i2c_set_bus_num(a)
54 #define CONFIG_SYS_MAX_I2C_BUS 1
55 #define I2C_GET_BUS() 0
56 #define I2C_SET_BUS(a)
59 /* define the I2C bus number for RTC and DTT if not already done */
60 #if !defined(CONFIG_SYS_RTC_BUS_NUM)
61 #define CONFIG_SYS_RTC_BUS_NUM 0
63 #if !defined(CONFIG_SYS_DTT_BUS_NUM)
64 #define CONFIG_SYS_DTT_BUS_NUM 0
66 #if !defined(CONFIG_SYS_SPD_BUS_NUM)
67 #define CONFIG_SYS_SPD_BUS_NUM 0
70 #ifndef I2C_SOFT_DECLARATIONS
71 # if defined(CONFIG_MPC8260)
72 # define I2C_SOFT_DECLARATIONS volatile ioport_t *iop = ioport_addr((immap_t *)CONFIG_SYS_IMMR, I2C_PORT);
73 # elif defined(CONFIG_8xx)
74 # define I2C_SOFT_DECLARATIONS volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
76 # define I2C_SOFT_DECLARATIONS
81 /* Set default value for the I2C bus speed on 8xx. In the
82 * future, we'll define these in all 8xx board config files.
84 #ifndef CONFIG_SYS_I2C_SPEED
85 #define CONFIG_SYS_I2C_SPEED 50000
90 * Many boards/controllers/drivers don't support an I2C slave interface so
91 * provide a default slave address for them for use in common code. A real
92 * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does
93 * support a slave interface.
95 #ifndef CONFIG_SYS_I2C_SLAVE
96 #define CONFIG_SYS_I2C_SLAVE 0xfe
100 * Initialization, must be called once on start up, may be called
101 * repeatedly to change the speed and slave addresses.
103 void i2c_init(int speed, int slaveaddr);
104 #ifdef CONFIG_SYS_I2C_INIT_BOARD
105 void i2c_init_board(void);
108 #if defined(CONFIG_I2C_MUX)
110 typedef struct _mux {
117 typedef struct _mux_device {
119 I2C_MUX *mux; /* List of muxes, to reach the device */
120 struct _mux_device *next;
123 int i2c_mux_add_device(I2C_MUX_DEVICE *dev);
125 I2C_MUX_DEVICE *i2c_mux_search_device(int id);
126 I2C_MUX_DEVICE *i2c_mux_ident_muxstring (uchar *buf);
127 int i2x_mux_select_mux(int bus);
128 int i2c_mux_ident_muxstring_f (uchar *buf);
132 * Probe the given I2C chip address. Returns 0 if a chip responded,
135 int i2c_probe(uchar chip);
138 * Read/Write interface:
139 * chip: I2C chip address, range 0..127
140 * addr: Memory (register) address within the chip
141 * alen: Number of bytes to use for addr (typically 1, 2 for larger
142 * memories, 0 for register type devices with only one
144 * buffer: Where to read/write the data
145 * len: How many bytes to read/write
147 * Returns: 0 on success, not 0 on failure
149 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len);
150 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
153 * Utility routines to read/write registers.
155 static inline u8 i2c_reg_read(u8 addr, u8 reg)
160 /* MPC8xx needs this. Maybe one day we can get rid of it. */
161 i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
165 printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg);
168 i2c_read(addr, reg, 1, &buf, 1);
173 static inline void i2c_reg_write(u8 addr, u8 reg, u8 val)
176 /* MPC8xx needs this. Maybe one day we can get rid of it. */
177 i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
181 printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n",
182 __func__, addr, reg, val);
185 i2c_write(addr, reg, 1, &val, 1);
189 * Functions for setting the current I2C bus and its speed
195 * Change the active I2C bus. Subsequent read/write calls will
198 * bus - bus index, zero based
200 * Returns: 0 on success, not 0 on failure
203 int i2c_set_bus_num(unsigned int bus);
208 * Returns index of currently active I2C bus. Zero-based.
211 unsigned int i2c_get_bus_num(void);
216 * Change the speed of the active I2C bus
218 * speed - bus speed in Hz
220 * Returns: 0 on success, not 0 on failure
223 int i2c_set_bus_speed(unsigned int);
228 * Returns speed of currently active I2C bus in Hz
231 unsigned int i2c_get_bus_speed(void);