1 | /* |
2 | * QEMU SMBus host (master) emulation. |
3 | * |
4 | * This code emulates SMBus transactions from the master point of view, |
5 | * it runs the individual I2C transaction to do the SMBus protocol |
6 | * over I2C. |
7 | * |
8 | * Copyright (c) 2007 CodeSourcery. |
9 | * Written by Paul Brook |
10 | * |
11 | * This code is licensed under the LGPL. |
12 | */ |
13 | |
14 | #include "qemu/osdep.h" |
15 | #include "hw/i2c/i2c.h" |
16 | #include "hw/i2c/smbus_master.h" |
17 | |
18 | /* Master device commands. */ |
19 | int smbus_quick_command(I2CBus *bus, uint8_t addr, int read) |
20 | { |
21 | if (i2c_start_transfer(bus, addr, read)) { |
22 | return -1; |
23 | } |
24 | i2c_end_transfer(bus); |
25 | return 0; |
26 | } |
27 | |
28 | int smbus_receive_byte(I2CBus *bus, uint8_t addr) |
29 | { |
30 | uint8_t data; |
31 | |
32 | if (i2c_start_transfer(bus, addr, 1)) { |
33 | return -1; |
34 | } |
35 | data = i2c_recv(bus); |
36 | i2c_nack(bus); |
37 | i2c_end_transfer(bus); |
38 | return data; |
39 | } |
40 | |
41 | int smbus_send_byte(I2CBus *bus, uint8_t addr, uint8_t data) |
42 | { |
43 | if (i2c_start_transfer(bus, addr, 0)) { |
44 | return -1; |
45 | } |
46 | i2c_send(bus, data); |
47 | i2c_end_transfer(bus); |
48 | return 0; |
49 | } |
50 | |
51 | int smbus_read_byte(I2CBus *bus, uint8_t addr, uint8_t command) |
52 | { |
53 | uint8_t data; |
54 | if (i2c_start_transfer(bus, addr, 0)) { |
55 | return -1; |
56 | } |
57 | i2c_send(bus, command); |
58 | if (i2c_start_transfer(bus, addr, 1)) { |
59 | i2c_end_transfer(bus); |
60 | return -1; |
61 | } |
62 | data = i2c_recv(bus); |
63 | i2c_nack(bus); |
64 | i2c_end_transfer(bus); |
65 | return data; |
66 | } |
67 | |
68 | int smbus_write_byte(I2CBus *bus, uint8_t addr, uint8_t command, uint8_t data) |
69 | { |
70 | if (i2c_start_transfer(bus, addr, 0)) { |
71 | return -1; |
72 | } |
73 | i2c_send(bus, command); |
74 | i2c_send(bus, data); |
75 | i2c_end_transfer(bus); |
76 | return 0; |
77 | } |
78 | |
79 | int smbus_read_word(I2CBus *bus, uint8_t addr, uint8_t command) |
80 | { |
81 | uint16_t data; |
82 | if (i2c_start_transfer(bus, addr, 0)) { |
83 | return -1; |
84 | } |
85 | i2c_send(bus, command); |
86 | if (i2c_start_transfer(bus, addr, 1)) { |
87 | i2c_end_transfer(bus); |
88 | return -1; |
89 | } |
90 | data = i2c_recv(bus); |
91 | data |= i2c_recv(bus) << 8; |
92 | i2c_nack(bus); |
93 | i2c_end_transfer(bus); |
94 | return data; |
95 | } |
96 | |
97 | int smbus_write_word(I2CBus *bus, uint8_t addr, uint8_t command, uint16_t data) |
98 | { |
99 | if (i2c_start_transfer(bus, addr, 0)) { |
100 | return -1; |
101 | } |
102 | i2c_send(bus, command); |
103 | i2c_send(bus, data & 0xff); |
104 | i2c_send(bus, data >> 8); |
105 | i2c_end_transfer(bus); |
106 | return 0; |
107 | } |
108 | |
109 | int smbus_read_block(I2CBus *bus, uint8_t addr, uint8_t command, uint8_t *data, |
110 | int len, bool recv_len, bool send_cmd) |
111 | { |
112 | int rlen; |
113 | int i; |
114 | |
115 | if (send_cmd) { |
116 | if (i2c_start_transfer(bus, addr, 0)) { |
117 | return -1; |
118 | } |
119 | i2c_send(bus, command); |
120 | } |
121 | if (i2c_start_transfer(bus, addr, 1)) { |
122 | if (send_cmd) { |
123 | i2c_end_transfer(bus); |
124 | } |
125 | return -1; |
126 | } |
127 | if (recv_len) { |
128 | rlen = i2c_recv(bus); |
129 | } else { |
130 | rlen = len; |
131 | } |
132 | if (rlen > len) { |
133 | rlen = 0; |
134 | } |
135 | for (i = 0; i < rlen; i++) { |
136 | data[i] = i2c_recv(bus); |
137 | } |
138 | i2c_nack(bus); |
139 | i2c_end_transfer(bus); |
140 | return rlen; |
141 | } |
142 | |
143 | int smbus_write_block(I2CBus *bus, uint8_t addr, uint8_t command, uint8_t *data, |
144 | int len, bool send_len) |
145 | { |
146 | int i; |
147 | |
148 | if (len > 32) { |
149 | len = 32; |
150 | } |
151 | |
152 | if (i2c_start_transfer(bus, addr, 0)) { |
153 | return -1; |
154 | } |
155 | i2c_send(bus, command); |
156 | if (send_len) { |
157 | i2c_send(bus, len); |
158 | } |
159 | for (i = 0; i < len; i++) { |
160 | i2c_send(bus, data[i]); |
161 | } |
162 | i2c_end_transfer(bus); |
163 | return 0; |
164 | } |
165 | |