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
|
/*
* *AT24C* series I2C EEPROM
*
* Copyright (c) 2015 Michael Davidsaver
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the LICENSE file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu/module.h"
#include "hw/i2c/i2c.h"
#include "hw/qdev-properties.h"
#include "hw/qdev-properties-system.h"
#include "sysemu/block-backend.h"
#include "qom/object.h"
/* #define DEBUG_AT24C */
#ifdef DEBUG_AT24C
#define DPRINTK(FMT, ...) printf(TYPE_AT24C_EE " : " FMT, ## __VA_ARGS__)
#else
#define DPRINTK(FMT, ...) do {} while (0)
#endif
#define ERR(FMT, ...) fprintf(stderr, TYPE_AT24C_EE " : " FMT, \
## __VA_ARGS__)
#define TYPE_AT24C_EE "at24c-eeprom"
typedef struct EEPROMState EEPROMState;
DECLARE_INSTANCE_CHECKER(EEPROMState, AT24C_EE,
TYPE_AT24C_EE)
struct EEPROMState {
I2CSlave parent_obj;
/* address counter */
uint16_t cur;
/* total size in bytes */
uint32_t rsize;
bool writable;
/* cells changed since last START? */
bool changed;
/* during WRITE, # of address bytes transfered */
uint8_t haveaddr;
uint8_t *mem;
BlockBackend *blk;
};
static
int at24c_eeprom_event(I2CSlave *s, enum i2c_event event)
{
EEPROMState *ee = container_of(s, EEPROMState, parent_obj);
switch (event) {
case I2C_START_SEND:
case I2C_START_RECV:
case I2C_FINISH:
ee->haveaddr = 0;
DPRINTK("clear\n");
if (ee->blk && ee->changed) {
int len = blk_pwrite(ee->blk, 0, ee->mem, ee->rsize, 0);
if (len != ee->rsize) {
ERR(TYPE_AT24C_EE
" : failed to write backing file\n");
}
DPRINTK("Wrote to backing file\n");
}
ee->changed = false;
break;
case I2C_NACK:
break;
}
return 0;
}
static
uint8_t at24c_eeprom_recv(I2CSlave *s)
{
EEPROMState *ee = AT24C_EE(s);
uint8_t ret;
ret = ee->mem[ee->cur];
ee->cur = (ee->cur + 1u) % ee->rsize;
DPRINTK("Recv %02x %c\n", ret, ret);
return ret;
}
static
int at24c_eeprom_send(I2CSlave *s, uint8_t data)
{
EEPROMState *ee = AT24C_EE(s);
if (ee->haveaddr < 2) {
ee->cur <<= 8;
ee->cur |= data;
ee->haveaddr++;
if (ee->haveaddr == 2) {
ee->cur %= ee->rsize;
DPRINTK("Set pointer %04x\n", ee->cur);
}
} else {
if (ee->writable) {
DPRINTK("Send %02x\n", data);
ee->mem[ee->cur] = data;
ee->changed = true;
} else {
DPRINTK("Send error %02x read-only\n", data);
}
ee->cur = (ee->cur + 1u) % ee->rsize;
}
return 0;
}
static void at24c_eeprom_realize(DeviceState *dev, Error **errp)
{
EEPROMState *ee = AT24C_EE(dev);
if (ee->blk) {
int64_t len = blk_getlength(ee->blk);
if (len != ee->rsize) {
error_setg(errp, "%s: Backing file size %" PRId64 " != %u",
TYPE_AT24C_EE, len, ee->rsize);
return;
}
if (blk_set_perm(ee->blk, BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE,
BLK_PERM_ALL, &error_fatal) < 0)
{
error_setg(errp, "%s: Backing file incorrect permission",
TYPE_AT24C_EE);
return;
}
}
ee->mem = g_malloc0(ee->rsize);
}
static
void at24c_eeprom_reset(DeviceState *state)
{
EEPROMState *ee = AT24C_EE(state);
ee->changed = false;
ee->cur = 0;
ee->haveaddr = 0;
memset(ee->mem, 0, ee->rsize);
if (ee->blk) {
int len = blk_pread(ee->blk, 0, ee->mem, ee->rsize);
if (len != ee->rsize) {
ERR(TYPE_AT24C_EE
" : Failed initial sync with backing file\n");
}
DPRINTK("Reset read backing file\n");
}
}
static Property at24c_eeprom_props[] = {
DEFINE_PROP_UINT32("rom-size", EEPROMState, rsize, 0),
DEFINE_PROP_BOOL("writable", EEPROMState, writable, true),
DEFINE_PROP_DRIVE("drive", EEPROMState, blk),
DEFINE_PROP_END_OF_LIST()
};
static
void at24c_eeprom_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
dc->realize = &at24c_eeprom_realize;
k->event = &at24c_eeprom_event;
k->recv = &at24c_eeprom_recv;
k->send = &at24c_eeprom_send;
device_class_set_props(dc, at24c_eeprom_props);
dc->reset = at24c_eeprom_reset;
}
static
const TypeInfo at24c_eeprom_type = {
.name = TYPE_AT24C_EE,
.parent = TYPE_I2C_SLAVE,
.instance_size = sizeof(EEPROMState),
.class_size = sizeof(I2CSlaveClass),
.class_init = at24c_eeprom_class_init,
};
static void at24c_eeprom_register(void)
{
type_register_static(&at24c_eeprom_type);
}
type_init(at24c_eeprom_register)
|
