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13#include "qemu/osdep.h"
14#include "hw/irq.h"
15#include "hw/ssi/ssi.h"
16#include "migration/vmstate.h"
17#include "qemu/module.h"
18#include "ui/console.h"
19#include "qom/object.h"
20
21struct ADS7846State {
22 SSIPeripheral ssidev;
23 qemu_irq interrupt;
24
25 int input[8];
26 int pressure;
27 int noise;
28
29 int cycle;
30 int output;
31};
32
33#define TYPE_ADS7846 "ads7846"
34OBJECT_DECLARE_SIMPLE_TYPE(ADS7846State, ADS7846)
35
36
37#define CB_PD0 (1 << 0)
38#define CB_PD1 (1 << 1)
39#define CB_SER (1 << 2)
40#define CB_MODE (1 << 3)
41#define CB_A0 (1 << 4)
42#define CB_A1 (1 << 5)
43#define CB_A2 (1 << 6)
44#define CB_START (1 << 7)
45
46#define X_AXIS_DMAX 3470
47#define X_AXIS_MIN 290
48#define Y_AXIS_DMAX 3450
49#define Y_AXIS_MIN 200
50
51#define ADS_VBAT 2000
52#define ADS_VAUX 2000
53#define ADS_TEMP0 2000
54#define ADS_TEMP1 3000
55#define ADS_XPOS(x, y) (X_AXIS_MIN + ((X_AXIS_DMAX * (x)) >> 15))
56#define ADS_YPOS(x, y) (Y_AXIS_MIN + ((Y_AXIS_DMAX * (y)) >> 15))
57#define ADS_Z1POS(x, y) 600
58#define ADS_Z2POS(x, y) (600 + 6000 / ADS_XPOS(x, y))
59
60static void ads7846_int_update(ADS7846State *s)
61{
62 if (s->interrupt)
63 qemu_set_irq(s->interrupt, s->pressure == 0);
64}
65
66static uint32_t ads7846_transfer(SSIPeripheral *dev, uint32_t value)
67{
68 ADS7846State *s = ADS7846(dev);
69
70 switch (s->cycle ++) {
71 case 0:
72 if (!(value & CB_START)) {
73 s->cycle = 0;
74 break;
75 }
76
77 s->output = s->input[(value >> 4) & 7];
78
79
80 s->noise = (s->noise + 3) & 7;
81 switch ((value >> 4) & 7) {
82 case 1: s->output += s->noise ^ 2; break;
83 case 3: s->output += s->noise ^ 0; break;
84 case 4: s->output += s->noise ^ 7; break;
85 case 5: s->output += s->noise ^ 5; break;
86 }
87
88 if (value & CB_MODE)
89 s->output >>= 4;
90
91 break;
92 case 1:
93 s->cycle = 0;
94 break;
95 }
96 return s->output;
97}
98
99static void ads7846_ts_event(void *opaque,
100 int x, int y, int z, int buttons_state)
101{
102 ADS7846State *s = opaque;
103
104 if (buttons_state) {
105 x = 0x7fff - x;
106 s->input[1] = ADS_XPOS(x, y);
107 s->input[3] = ADS_Z1POS(x, y);
108 s->input[4] = ADS_Z2POS(x, y);
109 s->input[5] = ADS_YPOS(x, y);
110 }
111
112 if (s->pressure == !buttons_state) {
113 s->pressure = !!buttons_state;
114
115 ads7846_int_update(s);
116 }
117}
118
119static int ads7856_post_load(void *opaque, int version_id)
120{
121 ADS7846State *s = opaque;
122
123 s->pressure = 0;
124 ads7846_int_update(s);
125 return 0;
126}
127
128static const VMStateDescription vmstate_ads7846 = {
129 .name = "ads7846",
130 .version_id = 1,
131 .minimum_version_id = 1,
132 .post_load = ads7856_post_load,
133 .fields = (VMStateField[]) {
134 VMSTATE_SSI_PERIPHERAL(ssidev, ADS7846State),
135 VMSTATE_INT32_ARRAY(input, ADS7846State, 8),
136 VMSTATE_INT32(noise, ADS7846State),
137 VMSTATE_INT32(cycle, ADS7846State),
138 VMSTATE_INT32(output, ADS7846State),
139 VMSTATE_END_OF_LIST()
140 }
141};
142
143static void ads7846_realize(SSIPeripheral *d, Error **errp)
144{
145 DeviceState *dev = DEVICE(d);
146 ADS7846State *s = ADS7846(d);
147
148 qdev_init_gpio_out(dev, &s->interrupt, 1);
149
150 s->input[0] = ADS_TEMP0;
151 s->input[2] = ADS_VBAT;
152 s->input[6] = ADS_VAUX;
153 s->input[7] = ADS_TEMP1;
154
155
156 qemu_add_mouse_event_handler(ads7846_ts_event, s, 1,
157 "QEMU ADS7846-driven Touchscreen");
158
159 ads7846_int_update(s);
160
161 vmstate_register(NULL, VMSTATE_INSTANCE_ID_ANY, &vmstate_ads7846, s);
162}
163
164static void ads7846_class_init(ObjectClass *klass, void *data)
165{
166 DeviceClass *dc = DEVICE_CLASS(klass);
167 SSIPeripheralClass *k = SSI_PERIPHERAL_CLASS(klass);
168
169 k->realize = ads7846_realize;
170 k->transfer = ads7846_transfer;
171 set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
172}
173
174static const TypeInfo ads7846_info = {
175 .name = TYPE_ADS7846,
176 .parent = TYPE_SSI_PERIPHERAL,
177 .instance_size = sizeof(ADS7846State),
178 .class_init = ads7846_class_init,
179};
180
181static void ads7846_register_types(void)
182{
183 type_register_static(&ads7846_info);
184}
185
186type_init(ads7846_register_types)
187