Merge remote-tracking branch 'remotes/philmd-gitlab/tags/renesas-20201027' into staging
[qemu.git] / hw / gpio / max7310.c
1 /*
2 * MAX7310 8-port GPIO expansion chip.
3 *
4 * Copyright (c) 2006 Openedhand Ltd.
5 * Written by Andrzej Zaborowski <balrog@zabor.org>
6 *
7 * This file is licensed under GNU GPL.
8 */
9
10 #include "qemu/osdep.h"
11 #include "hw/i2c/i2c.h"
12 #include "hw/irq.h"
13 #include "migration/vmstate.h"
14 #include "qemu/log.h"
15 #include "qemu/module.h"
16 #include "qom/object.h"
17
18 #define TYPE_MAX7310 "max7310"
19 OBJECT_DECLARE_SIMPLE_TYPE(MAX7310State, MAX7310)
20
21 struct MAX7310State {
22 I2CSlave parent_obj;
23
24 int i2c_command_byte;
25 int len;
26
27 uint8_t level;
28 uint8_t direction;
29 uint8_t polarity;
30 uint8_t status;
31 uint8_t command;
32 qemu_irq handler[8];
33 qemu_irq *gpio_in;
34 };
35
36 static void max7310_reset(DeviceState *dev)
37 {
38 MAX7310State *s = MAX7310(dev);
39
40 s->level &= s->direction;
41 s->direction = 0xff;
42 s->polarity = 0xf0;
43 s->status = 0x01;
44 s->command = 0x00;
45 }
46
47 static uint8_t max7310_rx(I2CSlave *i2c)
48 {
49 MAX7310State *s = MAX7310(i2c);
50
51 switch (s->command) {
52 case 0x00: /* Input port */
53 return s->level ^ s->polarity;
54
55 case 0x01: /* Output port */
56 return s->level & ~s->direction;
57
58 case 0x02: /* Polarity inversion */
59 return s->polarity;
60
61 case 0x03: /* Configuration */
62 return s->direction;
63
64 case 0x04: /* Timeout */
65 return s->status;
66
67 case 0xff: /* Reserved */
68 return 0xff;
69
70 default:
71 qemu_log_mask(LOG_UNIMP, "%s: Unsupported register 0x02%" PRIx8 "\n",
72 __func__, s->command);
73 break;
74 }
75 return 0xff;
76 }
77
78 static int max7310_tx(I2CSlave *i2c, uint8_t data)
79 {
80 MAX7310State *s = MAX7310(i2c);
81 uint8_t diff;
82 int line;
83
84 if (s->len ++ > 1) {
85 #ifdef VERBOSE
86 printf("%s: message too long (%i bytes)\n", __func__, s->len);
87 #endif
88 return 1;
89 }
90
91 if (s->i2c_command_byte) {
92 s->command = data;
93 s->i2c_command_byte = 0;
94 return 0;
95 }
96
97 switch (s->command) {
98 case 0x01: /* Output port */
99 for (diff = (data ^ s->level) & ~s->direction; diff;
100 diff &= ~(1 << line)) {
101 line = ctz32(diff);
102 if (s->handler[line])
103 qemu_set_irq(s->handler[line], (data >> line) & 1);
104 }
105 s->level = (s->level & s->direction) | (data & ~s->direction);
106 break;
107
108 case 0x02: /* Polarity inversion */
109 s->polarity = data;
110 break;
111
112 case 0x03: /* Configuration */
113 s->level &= ~(s->direction ^ data);
114 s->direction = data;
115 break;
116
117 case 0x04: /* Timeout */
118 s->status = data;
119 break;
120
121 case 0x00: /* Input port - ignore writes */
122 break;
123 default:
124 qemu_log_mask(LOG_UNIMP, "%s: Unsupported register 0x02%" PRIx8 "\n",
125 __func__, s->command);
126 return 1;
127 }
128
129 return 0;
130 }
131
132 static int max7310_event(I2CSlave *i2c, enum i2c_event event)
133 {
134 MAX7310State *s = MAX7310(i2c);
135 s->len = 0;
136
137 switch (event) {
138 case I2C_START_SEND:
139 s->i2c_command_byte = 1;
140 break;
141 case I2C_FINISH:
142 #ifdef VERBOSE
143 if (s->len == 1)
144 printf("%s: message too short (%i bytes)\n", __func__, s->len);
145 #endif
146 break;
147 default:
148 break;
149 }
150
151 return 0;
152 }
153
154 static const VMStateDescription vmstate_max7310 = {
155 .name = "max7310",
156 .version_id = 0,
157 .minimum_version_id = 0,
158 .fields = (VMStateField[]) {
159 VMSTATE_INT32(i2c_command_byte, MAX7310State),
160 VMSTATE_INT32(len, MAX7310State),
161 VMSTATE_UINT8(level, MAX7310State),
162 VMSTATE_UINT8(direction, MAX7310State),
163 VMSTATE_UINT8(polarity, MAX7310State),
164 VMSTATE_UINT8(status, MAX7310State),
165 VMSTATE_UINT8(command, MAX7310State),
166 VMSTATE_I2C_SLAVE(parent_obj, MAX7310State),
167 VMSTATE_END_OF_LIST()
168 }
169 };
170
171 static void max7310_gpio_set(void *opaque, int line, int level)
172 {
173 MAX7310State *s = (MAX7310State *) opaque;
174 assert(line >= 0 && line < ARRAY_SIZE(s->handler));
175
176 if (level)
177 s->level |= s->direction & (1 << line);
178 else
179 s->level &= ~(s->direction & (1 << line));
180 }
181
182 /* MAX7310 is SMBus-compatible (can be used with only SMBus protocols),
183 * but also accepts sequences that are not SMBus so return an I2C device. */
184 static void max7310_realize(DeviceState *dev, Error **errp)
185 {
186 I2CSlave *i2c = I2C_SLAVE(dev);
187 MAX7310State *s = MAX7310(dev);
188
189 qdev_init_gpio_in(&i2c->qdev, max7310_gpio_set, 8);
190 qdev_init_gpio_out(&i2c->qdev, s->handler, 8);
191 }
192
193 static void max7310_class_init(ObjectClass *klass, void *data)
194 {
195 DeviceClass *dc = DEVICE_CLASS(klass);
196 I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
197
198 dc->realize = max7310_realize;
199 k->event = max7310_event;
200 k->recv = max7310_rx;
201 k->send = max7310_tx;
202 dc->reset = max7310_reset;
203 dc->vmsd = &vmstate_max7310;
204 }
205
206 static const TypeInfo max7310_info = {
207 .name = TYPE_MAX7310,
208 .parent = TYPE_I2C_SLAVE,
209 .instance_size = sizeof(MAX7310State),
210 .class_init = max7310_class_init,
211 };
212
213 static void max7310_register_types(void)
214 {
215 type_register_static(&max7310_info);
216 }
217
218 type_init(max7310_register_types)