1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
|
/*
* MAX7310 8-port GPIO expansion chip.
*
* Copyright (c) 2006 Openedhand Ltd.
* Written by Andrzej Zaborowski <balrog@zabor.org>
*
* This file is licensed under GNU GPL.
*/
#include "qemu/osdep.h"
#include "hw/i2c/i2c.h"
#define TYPE_MAX7310 "max7310"
#define MAX7310(obj) OBJECT_CHECK(MAX7310State, (obj), TYPE_MAX7310)
typedef struct MAX7310State {
I2CSlave parent_obj;
int i2c_command_byte;
int len;
uint8_t level;
uint8_t direction;
uint8_t polarity;
uint8_t status;
uint8_t command;
qemu_irq handler[8];
qemu_irq *gpio_in;
} MAX7310State;
static void max7310_reset(DeviceState *dev)
{
MAX7310State *s = MAX7310(dev);
s->level &= s->direction;
s->direction = 0xff;
s->polarity = 0xf0;
s->status = 0x01;
s->command = 0x00;
}
static int max7310_rx(I2CSlave *i2c)
{
MAX7310State *s = MAX7310(i2c);
switch (s->command) {
case 0x00: /* Input port */
return s->level ^ s->polarity;
break;
case 0x01: /* Output port */
return s->level & ~s->direction;
break;
case 0x02: /* Polarity inversion */
return s->polarity;
case 0x03: /* Configuration */
return s->direction;
case 0x04: /* Timeout */
return s->status;
break;
case 0xff: /* Reserved */
return 0xff;
default:
#ifdef VERBOSE
printf("%s: unknown register %02x\n", __func__, s->command);
#endif
break;
}
return 0xff;
}
static int max7310_tx(I2CSlave *i2c, uint8_t data)
{
MAX7310State *s = MAX7310(i2c);
uint8_t diff;
int line;
if (s->len ++ > 1) {
#ifdef VERBOSE
printf("%s: message too long (%i bytes)\n", __func__, s->len);
#endif
return 1;
}
if (s->i2c_command_byte) {
s->command = data;
s->i2c_command_byte = 0;
return 0;
}
switch (s->command) {
case 0x01: /* Output port */
for (diff = (data ^ s->level) & ~s->direction; diff;
diff &= ~(1 << line)) {
line = ctz32(diff);
if (s->handler[line])
qemu_set_irq(s->handler[line], (data >> line) & 1);
}
s->level = (s->level & s->direction) | (data & ~s->direction);
break;
case 0x02: /* Polarity inversion */
s->polarity = data;
break;
case 0x03: /* Configuration */
s->level &= ~(s->direction ^ data);
s->direction = data;
break;
case 0x04: /* Timeout */
s->status = data;
break;
case 0x00: /* Input port - ignore writes */
break;
default:
#ifdef VERBOSE
printf("%s: unknown register %02x\n", __func__, s->command);
#endif
return 1;
}
return 0;
}
static int max7310_event(I2CSlave *i2c, enum i2c_event event)
{
MAX7310State *s = MAX7310(i2c);
s->len = 0;
switch (event) {
case I2C_START_SEND:
s->i2c_command_byte = 1;
break;
case I2C_FINISH:
#ifdef VERBOSE
if (s->len == 1)
printf("%s: message too short (%i bytes)\n", __func__, s->len);
#endif
break;
default:
break;
}
return 0;
}
static const VMStateDescription vmstate_max7310 = {
.name = "max7310",
.version_id = 0,
.minimum_version_id = 0,
.fields = (VMStateField[]) {
VMSTATE_INT32(i2c_command_byte, MAX7310State),
VMSTATE_INT32(len, MAX7310State),
VMSTATE_UINT8(level, MAX7310State),
VMSTATE_UINT8(direction, MAX7310State),
VMSTATE_UINT8(polarity, MAX7310State),
VMSTATE_UINT8(status, MAX7310State),
VMSTATE_UINT8(command, MAX7310State),
VMSTATE_I2C_SLAVE(parent_obj, MAX7310State),
VMSTATE_END_OF_LIST()
}
};
static void max7310_gpio_set(void *opaque, int line, int level)
{
MAX7310State *s = (MAX7310State *) opaque;
if (line >= ARRAY_SIZE(s->handler) || line < 0)
hw_error("bad GPIO line");
if (level)
s->level |= s->direction & (1 << line);
else
s->level &= ~(s->direction & (1 << line));
}
/* MAX7310 is SMBus-compatible (can be used with only SMBus protocols),
* but also accepts sequences that are not SMBus so return an I2C device. */
static void max7310_realize(DeviceState *dev, Error **errp)
{
I2CSlave *i2c = I2C_SLAVE(dev);
MAX7310State *s = MAX7310(dev);
qdev_init_gpio_in(&i2c->qdev, max7310_gpio_set, 8);
qdev_init_gpio_out(&i2c->qdev, s->handler, 8);
}
static void max7310_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
dc->realize = max7310_realize;
k->event = max7310_event;
k->recv = max7310_rx;
k->send = max7310_tx;
dc->reset = max7310_reset;
dc->vmsd = &vmstate_max7310;
}
static const TypeInfo max7310_info = {
.name = TYPE_MAX7310,
.parent = TYPE_I2C_SLAVE,
.instance_size = sizeof(MAX7310State),
.class_init = max7310_class_init,
};
static void max7310_register_types(void)
{
type_register_static(&max7310_info);
}
type_init(max7310_register_types)
|
