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13#include "qemu/osdep.h"
14#include "hw/ssi/ssi.h"
15#include "qemu/module.h"
16#include "ui/console.h"
17
18typedef struct {
19 SSISlave ssidev;
20 qemu_irq interrupt;
21
22 int input[8];
23 int pressure;
24 int noise;
25
26 int cycle;
27 int output;
28} ADS7846State;
29
30
31#define CB_PD0 (1 << 0)
32#define CB_PD1 (1 << 1)
33#define CB_SER (1 << 2)
34#define CB_MODE (1 << 3)
35#define CB_A0 (1 << 4)
36#define CB_A1 (1 << 5)
37#define CB_A2 (1 << 6)
38#define CB_START (1 << 7)
39
40#define X_AXIS_DMAX 3470
41#define X_AXIS_MIN 290
42#define Y_AXIS_DMAX 3450
43#define Y_AXIS_MIN 200
44
45#define ADS_VBAT 2000
46#define ADS_VAUX 2000
47#define ADS_TEMP0 2000
48#define ADS_TEMP1 3000
49#define ADS_XPOS(x, y) (X_AXIS_MIN + ((X_AXIS_DMAX * (x)) >> 15))
50#define ADS_YPOS(x, y) (Y_AXIS_MIN + ((Y_AXIS_DMAX * (y)) >> 15))
51#define ADS_Z1POS(x, y) 600
52#define ADS_Z2POS(x, y) (600 + 6000 / ADS_XPOS(x, y))
53
54static void ads7846_int_update(ADS7846State *s)
55{
56 if (s->interrupt)
57 qemu_set_irq(s->interrupt, s->pressure == 0);
58}
59
60static uint32_t ads7846_transfer(SSISlave *dev, uint32_t value)
61{
62 ADS7846State *s = FROM_SSI_SLAVE(ADS7846State, dev);
63
64 switch (s->cycle ++) {
65 case 0:
66 if (!(value & CB_START)) {
67 s->cycle = 0;
68 break;
69 }
70
71 s->output = s->input[(value >> 4) & 7];
72
73
74 s->noise = (s->noise + 3) & 7;
75 switch ((value >> 4) & 7) {
76 case 1: s->output += s->noise ^ 2; break;
77 case 3: s->output += s->noise ^ 0; break;
78 case 4: s->output += s->noise ^ 7; break;
79 case 5: s->output += s->noise ^ 5; break;
80 }
81
82 if (value & CB_MODE)
83 s->output >>= 4;
84
85 break;
86 case 1:
87 s->cycle = 0;
88 break;
89 }
90 return s->output;
91}
92
93static void ads7846_ts_event(void *opaque,
94 int x, int y, int z, int buttons_state)
95{
96 ADS7846State *s = opaque;
97
98 if (buttons_state) {
99 x = 0x7fff - x;
100 s->input[1] = ADS_XPOS(x, y);
101 s->input[3] = ADS_Z1POS(x, y);
102 s->input[4] = ADS_Z2POS(x, y);
103 s->input[5] = ADS_YPOS(x, y);
104 }
105
106 if (s->pressure == !buttons_state) {
107 s->pressure = !!buttons_state;
108
109 ads7846_int_update(s);
110 }
111}
112
113static int ads7856_post_load(void *opaque, int version_id)
114{
115 ADS7846State *s = opaque;
116
117 s->pressure = 0;
118 ads7846_int_update(s);
119 return 0;
120}
121
122static const VMStateDescription vmstate_ads7846 = {
123 .name = "ads7846",
124 .version_id = 1,
125 .minimum_version_id = 1,
126 .post_load = ads7856_post_load,
127 .fields = (VMStateField[]) {
128 VMSTATE_SSI_SLAVE(ssidev, ADS7846State),
129 VMSTATE_INT32_ARRAY(input, ADS7846State, 8),
130 VMSTATE_INT32(noise, ADS7846State),
131 VMSTATE_INT32(cycle, ADS7846State),
132 VMSTATE_INT32(output, ADS7846State),
133 VMSTATE_END_OF_LIST()
134 }
135};
136
137static void ads7846_realize(SSISlave *d, Error **errp)
138{
139 DeviceState *dev = DEVICE(d);
140 ADS7846State *s = FROM_SSI_SLAVE(ADS7846State, d);
141
142 qdev_init_gpio_out(dev, &s->interrupt, 1);
143
144 s->input[0] = ADS_TEMP0;
145 s->input[2] = ADS_VBAT;
146 s->input[6] = ADS_VAUX;
147 s->input[7] = ADS_TEMP1;
148
149
150 qemu_add_mouse_event_handler(ads7846_ts_event, s, 1,
151 "QEMU ADS7846-driven Touchscreen");
152
153 ads7846_int_update(s);
154
155 vmstate_register(NULL, -1, &vmstate_ads7846, s);
156}
157
158static void ads7846_class_init(ObjectClass *klass, void *data)
159{
160 SSISlaveClass *k = SSI_SLAVE_CLASS(klass);
161
162 k->realize = ads7846_realize;
163 k->transfer = ads7846_transfer;
164}
165
166static const TypeInfo ads7846_info = {
167 .name = "ads7846",
168 .parent = TYPE_SSI_SLAVE,
169 .instance_size = sizeof(ADS7846State),
170 .class_init = ads7846_class_init,
171};
172
173static void ads7846_register_types(void)
174{
175 type_register_static(&ads7846_info);
176}
177
178type_init(ads7846_register_types)
179