qdev: don't access name through info
[qemu.git] / hw / i2c.c
1 /*
2 * QEMU I2C bus interface.
3 *
4 * Copyright (c) 2007 CodeSourcery.
5 * Written by Paul Brook
6 *
7 * This code is licensed under the LGPL.
8 */
9
10 #include "i2c.h"
11
12 struct i2c_bus
13 {
14 BusState qbus;
15 i2c_slave *current_dev;
16 i2c_slave *dev;
17 uint8_t saved_address;
18 };
19
20 static struct BusInfo i2c_bus_info = {
21 .name = "I2C",
22 .size = sizeof(i2c_bus),
23 .props = (Property[]) {
24 DEFINE_PROP_UINT8("address", struct i2c_slave, address, 0),
25 DEFINE_PROP_END_OF_LIST(),
26 }
27 };
28
29 static void i2c_bus_pre_save(void *opaque)
30 {
31 i2c_bus *bus = opaque;
32
33 bus->saved_address = bus->current_dev ? bus->current_dev->address : -1;
34 }
35
36 static int i2c_bus_post_load(void *opaque, int version_id)
37 {
38 i2c_bus *bus = opaque;
39
40 /* The bus is loaded before attached devices, so load and save the
41 current device id. Devices will check themselves as loaded. */
42 bus->current_dev = NULL;
43 return 0;
44 }
45
46 static const VMStateDescription vmstate_i2c_bus = {
47 .name = "i2c_bus",
48 .version_id = 1,
49 .minimum_version_id = 1,
50 .minimum_version_id_old = 1,
51 .pre_save = i2c_bus_pre_save,
52 .post_load = i2c_bus_post_load,
53 .fields = (VMStateField []) {
54 VMSTATE_UINT8(saved_address, i2c_bus),
55 VMSTATE_END_OF_LIST()
56 }
57 };
58
59 /* Create a new I2C bus. */
60 i2c_bus *i2c_init_bus(DeviceState *parent, const char *name)
61 {
62 i2c_bus *bus;
63
64 bus = FROM_QBUS(i2c_bus, qbus_create(&i2c_bus_info, parent, name));
65 vmstate_register(NULL, -1, &vmstate_i2c_bus, bus);
66 return bus;
67 }
68
69 void i2c_set_slave_address(i2c_slave *dev, uint8_t address)
70 {
71 dev->address = address;
72 }
73
74 /* Return nonzero if bus is busy. */
75 int i2c_bus_busy(i2c_bus *bus)
76 {
77 return bus->current_dev != NULL;
78 }
79
80 /* Returns non-zero if the address is not valid. */
81 /* TODO: Make this handle multiple masters. */
82 int i2c_start_transfer(i2c_bus *bus, uint8_t address, int recv)
83 {
84 DeviceState *qdev;
85 i2c_slave *slave = NULL;
86
87 QTAILQ_FOREACH(qdev, &bus->qbus.children, sibling) {
88 i2c_slave *candidate = I2C_SLAVE_FROM_QDEV(qdev);
89 if (candidate->address == address) {
90 slave = candidate;
91 break;
92 }
93 }
94
95 if (!slave)
96 return 1;
97
98 /* If the bus is already busy, assume this is a repeated
99 start condition. */
100 bus->current_dev = slave;
101 slave->info->event(slave, recv ? I2C_START_RECV : I2C_START_SEND);
102 return 0;
103 }
104
105 void i2c_end_transfer(i2c_bus *bus)
106 {
107 i2c_slave *dev = bus->current_dev;
108
109 if (!dev)
110 return;
111
112 dev->info->event(dev, I2C_FINISH);
113
114 bus->current_dev = NULL;
115 }
116
117 int i2c_send(i2c_bus *bus, uint8_t data)
118 {
119 i2c_slave *dev = bus->current_dev;
120
121 if (!dev)
122 return -1;
123
124 return dev->info->send(dev, data);
125 }
126
127 int i2c_recv(i2c_bus *bus)
128 {
129 i2c_slave *dev = bus->current_dev;
130
131 if (!dev)
132 return -1;
133
134 return dev->info->recv(dev);
135 }
136
137 void i2c_nack(i2c_bus *bus)
138 {
139 i2c_slave *dev = bus->current_dev;
140
141 if (!dev)
142 return;
143
144 dev->info->event(dev, I2C_NACK);
145 }
146
147 static int i2c_slave_post_load(void *opaque, int version_id)
148 {
149 i2c_slave *dev = opaque;
150 i2c_bus *bus;
151 bus = FROM_QBUS(i2c_bus, qdev_get_parent_bus(&dev->qdev));
152 if (bus->saved_address == dev->address) {
153 bus->current_dev = dev;
154 }
155 return 0;
156 }
157
158 const VMStateDescription vmstate_i2c_slave = {
159 .name = "i2c_slave",
160 .version_id = 1,
161 .minimum_version_id = 1,
162 .minimum_version_id_old = 1,
163 .post_load = i2c_slave_post_load,
164 .fields = (VMStateField []) {
165 VMSTATE_UINT8(address, i2c_slave),
166 VMSTATE_END_OF_LIST()
167 }
168 };
169
170 static int i2c_slave_qdev_init(DeviceState *dev, DeviceInfo *base)
171 {
172 I2CSlaveInfo *info = container_of(base, I2CSlaveInfo, qdev);
173 i2c_slave *s = I2C_SLAVE_FROM_QDEV(dev);
174
175 s->info = info;
176
177 return info->init(s);
178 }
179
180 void i2c_register_slave(I2CSlaveInfo *info)
181 {
182 assert(info->qdev.size >= sizeof(i2c_slave));
183 info->qdev.init = i2c_slave_qdev_init;
184 info->qdev.bus_info = &i2c_bus_info;
185 qdev_register(&info->qdev);
186 }
187
188 DeviceState *i2c_create_slave(i2c_bus *bus, const char *name, uint8_t addr)
189 {
190 DeviceState *dev;
191
192 dev = qdev_create(&bus->qbus, name);
193 qdev_prop_set_uint8(dev, "address", addr);
194 qdev_init_nofail(dev);
195 return dev;
196 }