PPC: e500mc: add missing IVORs to bitmap
[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 I2CSlave *current_dev;
16 I2CSlave *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 I2CSlave, 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(I2CSlave *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 I2CSlave *slave = NULL;
86 I2CSlaveClass *sc;
87
88 QTAILQ_FOREACH(qdev, &bus->qbus.children, sibling) {
89 I2CSlave *candidate = I2C_SLAVE_FROM_QDEV(qdev);
90 if (candidate->address == address) {
91 slave = candidate;
92 break;
93 }
94 }
95
96 if (!slave) {
97 return 1;
98 }
99
100 sc = I2C_SLAVE_GET_CLASS(slave);
101 /* If the bus is already busy, assume this is a repeated
102 start condition. */
103 bus->current_dev = slave;
104 if (sc->event) {
105 sc->event(slave, recv ? I2C_START_RECV : I2C_START_SEND);
106 }
107 return 0;
108 }
109
110 void i2c_end_transfer(i2c_bus *bus)
111 {
112 I2CSlave *dev = bus->current_dev;
113 I2CSlaveClass *sc;
114
115 if (!dev) {
116 return;
117 }
118
119 sc = I2C_SLAVE_GET_CLASS(dev);
120 if (sc->event) {
121 sc->event(dev, I2C_FINISH);
122 }
123
124 bus->current_dev = NULL;
125 }
126
127 int i2c_send(i2c_bus *bus, uint8_t data)
128 {
129 I2CSlave *dev = bus->current_dev;
130 I2CSlaveClass *sc;
131
132 if (!dev) {
133 return -1;
134 }
135
136 sc = I2C_SLAVE_GET_CLASS(dev);
137 if (sc->send) {
138 return sc->send(dev, data);
139 }
140
141 return -1;
142 }
143
144 int i2c_recv(i2c_bus *bus)
145 {
146 I2CSlave *dev = bus->current_dev;
147 I2CSlaveClass *sc;
148
149 if (!dev) {
150 return -1;
151 }
152
153 sc = I2C_SLAVE_GET_CLASS(dev);
154 if (sc->recv) {
155 return sc->recv(dev);
156 }
157
158 return -1;
159 }
160
161 void i2c_nack(i2c_bus *bus)
162 {
163 I2CSlave *dev = bus->current_dev;
164 I2CSlaveClass *sc;
165
166 if (!dev) {
167 return;
168 }
169
170 sc = I2C_SLAVE_GET_CLASS(dev);
171 if (sc->event) {
172 sc->event(dev, I2C_NACK);
173 }
174 }
175
176 static int i2c_slave_post_load(void *opaque, int version_id)
177 {
178 I2CSlave *dev = opaque;
179 i2c_bus *bus;
180 bus = FROM_QBUS(i2c_bus, qdev_get_parent_bus(&dev->qdev));
181 if (bus->saved_address == dev->address) {
182 bus->current_dev = dev;
183 }
184 return 0;
185 }
186
187 const VMStateDescription vmstate_i2c_slave = {
188 .name = "I2CSlave",
189 .version_id = 1,
190 .minimum_version_id = 1,
191 .minimum_version_id_old = 1,
192 .post_load = i2c_slave_post_load,
193 .fields = (VMStateField []) {
194 VMSTATE_UINT8(address, I2CSlave),
195 VMSTATE_END_OF_LIST()
196 }
197 };
198
199 static int i2c_slave_qdev_init(DeviceState *dev, DeviceInfo *base)
200 {
201 I2CSlave *s = I2C_SLAVE_FROM_QDEV(dev);
202 I2CSlaveClass *sc = I2C_SLAVE_GET_CLASS(s);
203
204 return sc->init(s);
205 }
206
207 void i2c_register_slave_subclass(DeviceInfo *info, const char *parent)
208 {
209 assert(info->size >= sizeof(I2CSlave));
210 info->init = i2c_slave_qdev_init;
211 info->bus_info = &i2c_bus_info;
212 qdev_register_subclass(info, parent);
213 }
214
215 void i2c_register_slave(DeviceInfo *info)
216 {
217 i2c_register_slave_subclass(info, TYPE_I2C_SLAVE);
218 }
219
220 DeviceState *i2c_create_slave(i2c_bus *bus, const char *name, uint8_t addr)
221 {
222 DeviceState *dev;
223
224 dev = qdev_create(&bus->qbus, name);
225 qdev_prop_set_uint8(dev, "address", addr);
226 qdev_init_nofail(dev);
227 return dev;
228 }
229
230 static TypeInfo i2c_slave_type_info = {
231 .name = TYPE_I2C_SLAVE,
232 .parent = TYPE_DEVICE,
233 .instance_size = sizeof(I2CSlave),
234 .abstract = true,
235 .class_size = sizeof(I2CSlaveClass),
236 };
237
238 static void i2c_slave_register_devices(void)
239 {
240 type_register_static(&i2c_slave_type_info);
241 }
242
243 device_init(i2c_slave_register_devices);