xref: /openbmc/qemu/include/hw/i2c/i2c.h (revision 1fd6bb44)
1 #ifndef QEMU_I2C_H
2 #define QEMU_I2C_H
3 
4 #include "hw/qdev.h"
5 
6 /* The QEMU I2C implementation only supports simple transfers that complete
7    immediately.  It does not support slave devices that need to be able to
8    defer their response (eg. CPU slave interfaces where the data is supplied
9    by the device driver in response to an interrupt).  */
10 
11 enum i2c_event {
12     I2C_START_RECV,
13     I2C_START_SEND,
14     I2C_FINISH,
15     I2C_NACK /* Masker NACKed a receive byte.  */
16 };
17 
18 typedef struct I2CSlave I2CSlave;
19 
20 #define TYPE_I2C_SLAVE "i2c-slave"
21 #define I2C_SLAVE(obj) \
22      OBJECT_CHECK(I2CSlave, (obj), TYPE_I2C_SLAVE)
23 #define I2C_SLAVE_CLASS(klass) \
24      OBJECT_CLASS_CHECK(I2CSlaveClass, (klass), TYPE_I2C_SLAVE)
25 #define I2C_SLAVE_GET_CLASS(obj) \
26      OBJECT_GET_CLASS(I2CSlaveClass, (obj), TYPE_I2C_SLAVE)
27 
28 typedef struct I2CSlaveClass
29 {
30     DeviceClass parent_class;
31 
32     /* Callbacks provided by the device.  */
33     int (*init)(I2CSlave *dev);
34 
35     /* Master to slave.  */
36     int (*send)(I2CSlave *s, uint8_t data);
37 
38     /* Slave to master.  */
39     int (*recv)(I2CSlave *s);
40 
41     /* Notify the slave of a bus state change.  */
42     void (*event)(I2CSlave *s, enum i2c_event event);
43 } I2CSlaveClass;
44 
45 struct I2CSlave
46 {
47     DeviceState qdev;
48 
49     /* Remaining fields for internal use by the I2C code.  */
50     uint8_t address;
51 };
52 
53 i2c_bus *i2c_init_bus(DeviceState *parent, const char *name);
54 void i2c_set_slave_address(I2CSlave *dev, uint8_t address);
55 int i2c_bus_busy(i2c_bus *bus);
56 int i2c_start_transfer(i2c_bus *bus, uint8_t address, int recv);
57 void i2c_end_transfer(i2c_bus *bus);
58 void i2c_nack(i2c_bus *bus);
59 int i2c_send(i2c_bus *bus, uint8_t data);
60 int i2c_recv(i2c_bus *bus);
61 
62 #define FROM_I2C_SLAVE(type, dev) DO_UPCAST(type, i2c, dev)
63 
64 DeviceState *i2c_create_slave(i2c_bus *bus, const char *name, uint8_t addr);
65 
66 /* wm8750.c */
67 void wm8750_data_req_set(DeviceState *dev,
68                 void (*data_req)(void *, int, int), void *opaque);
69 void wm8750_dac_dat(void *opaque, uint32_t sample);
70 uint32_t wm8750_adc_dat(void *opaque);
71 void *wm8750_dac_buffer(void *opaque, int samples);
72 void wm8750_dac_commit(void *opaque);
73 void wm8750_set_bclk_in(void *opaque, int new_hz);
74 
75 /* lm832x.c */
76 void lm832x_key_event(DeviceState *dev, int key, int state);
77 
78 extern const VMStateDescription vmstate_i2c_slave;
79 
80 #define VMSTATE_I2C_SLAVE(_field, _state) {                          \
81     .name       = (stringify(_field)),                               \
82     .size       = sizeof(I2CSlave),                                  \
83     .vmsd       = &vmstate_i2c_slave,                                \
84     .flags      = VMS_STRUCT,                                        \
85     .offset     = vmstate_offset_value(_state, _field, I2CSlave),    \
86 }
87 
88 #endif
89