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10#include "qemu/osdep.h"
11#include "hw/i2c/i2c.h"
12
13typedef struct I2CNode I2CNode;
14
15struct I2CNode {
16 I2CSlave *elt;
17 QLIST_ENTRY(I2CNode) next;
18};
19
20#define I2C_BROADCAST 0x00
21
22struct I2CBus
23{
24 BusState qbus;
25 QLIST_HEAD(, I2CNode) current_devs;
26 uint8_t saved_address;
27 bool broadcast;
28};
29
30static Property i2c_props[] = {
31 DEFINE_PROP_UINT8("address", struct I2CSlave, address, 0),
32 DEFINE_PROP_END_OF_LIST(),
33};
34
35#define TYPE_I2C_BUS "i2c-bus"
36#define I2C_BUS(obj) OBJECT_CHECK(I2CBus, (obj), TYPE_I2C_BUS)
37
38static const TypeInfo i2c_bus_info = {
39 .name = TYPE_I2C_BUS,
40 .parent = TYPE_BUS,
41 .instance_size = sizeof(I2CBus),
42};
43
44static void i2c_bus_pre_save(void *opaque)
45{
46 I2CBus *bus = opaque;
47
48 bus->saved_address = -1;
49 if (!QLIST_EMPTY(&bus->current_devs)) {
50 if (!bus->broadcast) {
51 bus->saved_address = QLIST_FIRST(&bus->current_devs)->elt->address;
52 } else {
53 bus->saved_address = I2C_BROADCAST;
54 }
55 }
56}
57
58static const VMStateDescription vmstate_i2c_bus = {
59 .name = "i2c_bus",
60 .version_id = 1,
61 .minimum_version_id = 1,
62 .pre_save = i2c_bus_pre_save,
63 .fields = (VMStateField[]) {
64 VMSTATE_UINT8(saved_address, I2CBus),
65 VMSTATE_END_OF_LIST()
66 }
67};
68
69
70I2CBus *i2c_init_bus(DeviceState *parent, const char *name)
71{
72 I2CBus *bus;
73
74 bus = I2C_BUS(qbus_create(TYPE_I2C_BUS, parent, name));
75 QLIST_INIT(&bus->current_devs);
76 vmstate_register(NULL, -1, &vmstate_i2c_bus, bus);
77 return bus;
78}
79
80void i2c_set_slave_address(I2CSlave *dev, uint8_t address)
81{
82 dev->address = address;
83}
84
85
86int i2c_bus_busy(I2CBus *bus)
87{
88 return !QLIST_EMPTY(&bus->current_devs);
89}
90
91
92
93int i2c_start_transfer(I2CBus *bus, uint8_t address, int recv)
94{
95 BusChild *kid;
96 I2CSlaveClass *sc;
97 I2CNode *node;
98
99 if (address == I2C_BROADCAST) {
100
101
102
103
104 bus->broadcast = true;
105 }
106
107 QTAILQ_FOREACH(kid, &bus->qbus.children, sibling) {
108 DeviceState *qdev = kid->child;
109 I2CSlave *candidate = I2C_SLAVE(qdev);
110 if ((candidate->address == address) || (bus->broadcast)) {
111 node = g_malloc(sizeof(struct I2CNode));
112 node->elt = candidate;
113 QLIST_INSERT_HEAD(&bus->current_devs, node, next);
114 if (!bus->broadcast) {
115 break;
116 }
117 }
118 }
119
120 if (QLIST_EMPTY(&bus->current_devs)) {
121 return 1;
122 }
123
124 QLIST_FOREACH(node, &bus->current_devs, next) {
125 sc = I2C_SLAVE_GET_CLASS(node->elt);
126
127
128 if (sc->event) {
129 sc->event(node->elt, recv ? I2C_START_RECV : I2C_START_SEND);
130 }
131 }
132 return 0;
133}
134
135void i2c_end_transfer(I2CBus *bus)
136{
137 I2CSlaveClass *sc;
138 I2CNode *node, *next;
139
140 if (QLIST_EMPTY(&bus->current_devs)) {
141 return;
142 }
143
144 QLIST_FOREACH_SAFE(node, &bus->current_devs, next, next) {
145 sc = I2C_SLAVE_GET_CLASS(node->elt);
146 if (sc->event) {
147 sc->event(node->elt, I2C_FINISH);
148 }
149 QLIST_REMOVE(node, next);
150 g_free(node);
151 }
152 bus->broadcast = false;
153}
154
155int i2c_send_recv(I2CBus *bus, uint8_t *data, bool send)
156{
157 I2CSlaveClass *sc;
158 I2CNode *node;
159 int ret = 0;
160
161 if (send) {
162 QLIST_FOREACH(node, &bus->current_devs, next) {
163 sc = I2C_SLAVE_GET_CLASS(node->elt);
164 if (sc->send) {
165 ret = ret || sc->send(node->elt, *data);
166 } else {
167 ret = -1;
168 }
169 }
170 return ret ? -1 : 0;
171 } else {
172 if ((QLIST_EMPTY(&bus->current_devs)) || (bus->broadcast)) {
173 return -1;
174 }
175
176 sc = I2C_SLAVE_GET_CLASS(QLIST_FIRST(&bus->current_devs)->elt);
177 if (sc->recv) {
178 ret = sc->recv(QLIST_FIRST(&bus->current_devs)->elt);
179 if (ret < 0) {
180 return ret;
181 } else {
182 *data = ret;
183 return 0;
184 }
185 }
186 return -1;
187 }
188}
189
190int i2c_send(I2CBus *bus, uint8_t data)
191{
192 return i2c_send_recv(bus, &data, true);
193}
194
195int i2c_recv(I2CBus *bus)
196{
197 uint8_t data;
198 int ret = i2c_send_recv(bus, &data, false);
199
200 return ret < 0 ? ret : data;
201}
202
203void i2c_nack(I2CBus *bus)
204{
205 I2CSlaveClass *sc;
206 I2CNode *node;
207
208 if (QLIST_EMPTY(&bus->current_devs)) {
209 return;
210 }
211
212 QLIST_FOREACH(node, &bus->current_devs, next) {
213 sc = I2C_SLAVE_GET_CLASS(node->elt);
214 if (sc->event) {
215 sc->event(node->elt, I2C_NACK);
216 }
217 }
218}
219
220static int i2c_slave_post_load(void *opaque, int version_id)
221{
222 I2CSlave *dev = opaque;
223 I2CBus *bus;
224 I2CNode *node;
225
226 bus = I2C_BUS(qdev_get_parent_bus(DEVICE(dev)));
227 if ((bus->saved_address == dev->address) ||
228 (bus->saved_address == I2C_BROADCAST)) {
229 node = g_malloc(sizeof(struct I2CNode));
230 node->elt = dev;
231 QLIST_INSERT_HEAD(&bus->current_devs, node, next);
232 }
233 return 0;
234}
235
236const VMStateDescription vmstate_i2c_slave = {
237 .name = "I2CSlave",
238 .version_id = 1,
239 .minimum_version_id = 1,
240 .post_load = i2c_slave_post_load,
241 .fields = (VMStateField[]) {
242 VMSTATE_UINT8(address, I2CSlave),
243 VMSTATE_END_OF_LIST()
244 }
245};
246
247static int i2c_slave_qdev_init(DeviceState *dev)
248{
249 I2CSlave *s = I2C_SLAVE(dev);
250 I2CSlaveClass *sc = I2C_SLAVE_GET_CLASS(s);
251
252 return sc->init(s);
253}
254
255DeviceState *i2c_create_slave(I2CBus *bus, const char *name, uint8_t addr)
256{
257 DeviceState *dev;
258
259 dev = qdev_create(&bus->qbus, name);
260 qdev_prop_set_uint8(dev, "address", addr);
261 qdev_init_nofail(dev);
262 return dev;
263}
264
265static void i2c_slave_class_init(ObjectClass *klass, void *data)
266{
267 DeviceClass *k = DEVICE_CLASS(klass);
268 k->init = i2c_slave_qdev_init;
269 set_bit(DEVICE_CATEGORY_MISC, k->categories);
270 k->bus_type = TYPE_I2C_BUS;
271 k->props = i2c_props;
272}
273
274static const TypeInfo i2c_slave_type_info = {
275 .name = TYPE_I2C_SLAVE,
276 .parent = TYPE_DEVICE,
277 .instance_size = sizeof(I2CSlave),
278 .abstract = true,
279 .class_size = sizeof(I2CSlaveClass),
280 .class_init = i2c_slave_class_init,
281};
282
283static void i2c_slave_register_types(void)
284{
285 type_register_static(&i2c_bus_info);
286 type_register_static(&i2c_slave_type_info);
287}
288
289type_init(i2c_slave_register_types)
290