1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2009 Sergey Kubushyn <ksi@koi8.net>
4 *
5 * (C) Copyright 2012
6 * Heiko Schocher, DENX Software Engineering, hs@denx.de.
7 *
8 * Multibus/multiadapter I2C core functions (wrappers)
9 */
10 #include <config.h>
11 #include <i2c.h>
12 #include <linker_lists.h>
13 #include <asm/global_data.h>
14
i2c_get_adapter(int index)15 struct i2c_adapter *i2c_get_adapter(int index)
16 {
17 struct i2c_adapter *i2c_adap_p = ll_entry_start(struct i2c_adapter,
18 i2c);
19 int max = ll_entry_count(struct i2c_adapter, i2c);
20 int i;
21
22 if (index >= max) {
23 printf("Error, wrong i2c adapter %d max %d possible\n",
24 index, max);
25 return i2c_adap_p;
26 }
27 if (index == 0)
28 return i2c_adap_p;
29
30 for (i = 0; i < index; i++)
31 i2c_adap_p++;
32
33 return i2c_adap_p;
34 }
35
36 DECLARE_GLOBAL_DATA_PTR;
37
38 /*
39 * i2c_init_bus():
40 * ---------------
41 *
42 * Initializes one bus. Will initialize the parent adapter. No current bus
43 * changes, no mux (if any) setup.
44 */
i2c_init_bus(unsigned int bus_no,int speed,int slaveaddr)45 static void i2c_init_bus(unsigned int bus_no, int speed, int slaveaddr)
46 {
47 if (bus_no >= CFG_SYS_NUM_I2C_BUSES)
48 return;
49
50 I2C_ADAP->init(I2C_ADAP, speed, slaveaddr);
51
52 if (gd->flags & GD_FLG_RELOC) {
53 I2C_ADAP->init_done = 1;
54 I2C_ADAP->speed = speed;
55 I2C_ADAP->slaveaddr = slaveaddr;
56 }
57 }
58
59 /* implement possible board specific board init */
i2c_init_board(void)60 __weak void i2c_init_board(void)
61 {
62 }
63
64 /*
65 * i2c_init_all():
66 *
67 * not longer needed, will deleted. Actual init the SPD_BUS
68 * for compatibility.
69 * i2c_adap[] must be initialized beforehead with function pointers and
70 * data, including speed and slaveaddr.
71 */
i2c_init_all(void)72 void i2c_init_all(void)
73 {
74 i2c_init_board();
75 i2c_set_bus_num(CONFIG_SYS_SPD_BUS_NUM);
76 return;
77 }
78
79 /*
80 * i2c_get_bus_num():
81 * ------------------
82 *
83 * Returns index of currently active I2C bus. Zero-based.
84 */
i2c_get_bus_num(void)85 unsigned int i2c_get_bus_num(void)
86 {
87 return gd->cur_i2c_bus;
88 }
89
90 /*
91 * i2c_set_bus_num():
92 * ------------------
93 *
94 * Change the active I2C bus. Subsequent read/write calls will
95 * go to this one. Sets all of the muxes in a proper condition
96 * if that bus is behind muxes.
97 * If previously selected bus is behind the muxes turns off all the
98 * muxes along the path to that bus.
99 *
100 * bus - bus index, zero based
101 *
102 * Returns: 0 on success, not 0 on failure
103 */
i2c_set_bus_num(unsigned int bus)104 int i2c_set_bus_num(unsigned int bus)
105 {
106 int max;
107
108 if ((bus == I2C_BUS) && (I2C_ADAP->init_done > 0))
109 return 0;
110
111 max = ll_entry_count(struct i2c_adapter, i2c);
112 if (I2C_ADAPTER(bus) >= max) {
113 printf("Error, wrong i2c adapter %d max %d possible\n",
114 I2C_ADAPTER(bus), max);
115 return -2;
116 }
117
118 gd->cur_i2c_bus = bus;
119 if (I2C_ADAP->init_done == 0)
120 i2c_init_bus(bus, I2C_ADAP->speed, I2C_ADAP->slaveaddr);
121
122 return 0;
123 }
124
125 /*
126 * Probe the given I2C chip address. Returns 0 if a chip responded,
127 * not 0 on failure.
128 */
i2c_probe(uint8_t chip)129 int i2c_probe(uint8_t chip)
130 {
131 return I2C_ADAP->probe(I2C_ADAP, chip);
132 }
133
134 /*
135 * Read/Write interface:
136 * chip: I2C chip address, range 0..127
137 * addr: Memory (register) address within the chip
138 * alen: Number of bytes to use for addr (typically 1, 2 for larger
139 * memories, 0 for register type devices with only one
140 * register)
141 * buffer: Where to read/write the data
142 * len: How many bytes to read/write
143 *
144 * Returns: 0 on success, not 0 on failure
145 */
i2c_read(uint8_t chip,unsigned int addr,int alen,uint8_t * buffer,int len)146 int i2c_read(uint8_t chip, unsigned int addr, int alen,
147 uint8_t *buffer, int len)
148 {
149 return I2C_ADAP->read(I2C_ADAP, chip, addr, alen, buffer, len);
150 }
151
i2c_write(uint8_t chip,unsigned int addr,int alen,uint8_t * buffer,int len)152 int i2c_write(uint8_t chip, unsigned int addr, int alen,
153 uint8_t *buffer, int len)
154 {
155 return I2C_ADAP->write(I2C_ADAP, chip, addr, alen, buffer, len);
156 }
157
i2c_set_bus_speed(unsigned int speed)158 unsigned int i2c_set_bus_speed(unsigned int speed)
159 {
160 unsigned int ret;
161
162 if (I2C_ADAP->set_bus_speed == NULL)
163 return 0;
164 ret = I2C_ADAP->set_bus_speed(I2C_ADAP, speed);
165 if (gd->flags & GD_FLG_RELOC)
166 I2C_ADAP->speed = (ret == 0) ? speed : 0;
167
168 return ret;
169 }
170
i2c_get_bus_speed(void)171 unsigned int i2c_get_bus_speed(void)
172 {
173 struct i2c_adapter *cur = I2C_ADAP;
174 return cur->speed;
175 }
176
i2c_reg_read(uint8_t addr,uint8_t reg)177 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg)
178 {
179 uint8_t buf;
180
181 i2c_read(addr, reg, 1, &buf, 1);
182
183 #ifdef DEBUG
184 printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x\n",
185 __func__, i2c_get_bus_num(), addr, reg, buf);
186 #endif
187
188 return buf;
189 }
190
i2c_reg_write(uint8_t addr,uint8_t reg,uint8_t val)191 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val)
192 {
193 #ifdef DEBUG
194 printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x\n",
195 __func__, i2c_get_bus_num(), addr, reg, val);
196 #endif
197
198 i2c_write(addr, reg, 1, &val, 1);
199 }
200
i2c_init(int speed,int slaveaddr)201 __weak void i2c_init(int speed, int slaveaddr)
202 {
203 i2c_init_bus(i2c_get_bus_num(), speed, slaveaddr);
204 }
205