1 /* 2 * Silicon Image SiI9022 3 * 4 * This is a pretty hollow emulation: all we do is acknowledge that we 5 * exist (chip ID) and confirm that we get switched over into DDC mode 6 * so the emulated host can proceed to read out EDID data. All subsequent 7 * set-up of connectors etc will be acknowledged and ignored. 8 * 9 * Copyright (C) 2018 Linus Walleij 10 * 11 * This work is licensed under the terms of the GNU GPL, version 2 or later. 12 * See the COPYING file in the top-level directory. 13 * SPDX-License-Identifier: GPL-2.0-or-later 14 */ 15 16 #include "qemu/osdep.h" 17 #include "qemu-common.h" 18 #include "hw/i2c/i2c.h" 19 #include "hw/i2c/i2c-ddc.h" 20 #include "trace.h" 21 22 #define SII9022_SYS_CTRL_DATA 0x1a 23 #define SII9022_SYS_CTRL_PWR_DWN 0x10 24 #define SII9022_SYS_CTRL_AV_MUTE 0x08 25 #define SII9022_SYS_CTRL_DDC_BUS_REQ 0x04 26 #define SII9022_SYS_CTRL_DDC_BUS_GRTD 0x02 27 #define SII9022_SYS_CTRL_OUTPUT_MODE 0x01 28 #define SII9022_SYS_CTRL_OUTPUT_HDMI 1 29 #define SII9022_SYS_CTRL_OUTPUT_DVI 0 30 #define SII9022_REG_CHIPID 0x1b 31 #define SII9022_INT_ENABLE 0x3c 32 #define SII9022_INT_STATUS 0x3d 33 #define SII9022_INT_STATUS_HOTPLUG 0x01; 34 #define SII9022_INT_STATUS_PLUGGED 0x04; 35 36 #define TYPE_SII9022 "sii9022" 37 #define SII9022(obj) OBJECT_CHECK(sii9022_state, (obj), TYPE_SII9022) 38 39 typedef struct sii9022_state { 40 I2CSlave parent_obj; 41 uint8_t ptr; 42 bool addr_byte; 43 bool ddc_req; 44 bool ddc_skip_finish; 45 bool ddc; 46 } sii9022_state; 47 48 static const VMStateDescription vmstate_sii9022 = { 49 .name = "sii9022", 50 .version_id = 1, 51 .minimum_version_id = 1, 52 .fields = (VMStateField[]) { 53 VMSTATE_I2C_SLAVE(parent_obj, sii9022_state), 54 VMSTATE_UINT8(ptr, sii9022_state), 55 VMSTATE_BOOL(addr_byte, sii9022_state), 56 VMSTATE_BOOL(ddc_req, sii9022_state), 57 VMSTATE_BOOL(ddc_skip_finish, sii9022_state), 58 VMSTATE_BOOL(ddc, sii9022_state), 59 VMSTATE_END_OF_LIST() 60 } 61 }; 62 63 static int sii9022_event(I2CSlave *i2c, enum i2c_event event) 64 { 65 sii9022_state *s = SII9022(i2c); 66 67 switch (event) { 68 case I2C_START_SEND: 69 s->addr_byte = true; 70 break; 71 case I2C_START_RECV: 72 break; 73 case I2C_FINISH: 74 break; 75 case I2C_NACK: 76 break; 77 } 78 79 return 0; 80 } 81 82 static int sii9022_rx(I2CSlave *i2c) 83 { 84 sii9022_state *s = SII9022(i2c); 85 uint8_t res = 0x00; 86 87 switch (s->ptr) { 88 case SII9022_SYS_CTRL_DATA: 89 if (s->ddc_req) { 90 /* Acknowledge DDC bus request */ 91 res = SII9022_SYS_CTRL_DDC_BUS_GRTD | SII9022_SYS_CTRL_DDC_BUS_REQ; 92 } 93 break; 94 case SII9022_REG_CHIPID: 95 res = 0xb0; 96 break; 97 case SII9022_INT_STATUS: 98 /* Something is cold-plugged in, no interrupts */ 99 res = SII9022_INT_STATUS_PLUGGED; 100 break; 101 default: 102 break; 103 } 104 105 trace_sii9022_read_reg(s->ptr, res); 106 s->ptr++; 107 108 return res; 109 } 110 111 static int sii9022_tx(I2CSlave *i2c, uint8_t data) 112 { 113 sii9022_state *s = SII9022(i2c); 114 115 if (s->addr_byte) { 116 s->ptr = data; 117 s->addr_byte = false; 118 return 0; 119 } 120 121 switch (s->ptr) { 122 case SII9022_SYS_CTRL_DATA: 123 if (data & SII9022_SYS_CTRL_DDC_BUS_REQ) { 124 s->ddc_req = true; 125 if (data & SII9022_SYS_CTRL_DDC_BUS_GRTD) { 126 s->ddc = true; 127 /* Skip this finish since we just switched to DDC */ 128 s->ddc_skip_finish = true; 129 trace_sii9022_switch_mode("DDC"); 130 } 131 } else { 132 s->ddc_req = false; 133 s->ddc = false; 134 trace_sii9022_switch_mode("normal"); 135 } 136 break; 137 default: 138 break; 139 } 140 141 trace_sii9022_write_reg(s->ptr, data); 142 s->ptr++; 143 144 return 0; 145 } 146 147 static void sii9022_reset(DeviceState *dev) 148 { 149 sii9022_state *s = SII9022(dev); 150 151 s->ptr = 0; 152 s->addr_byte = false; 153 s->ddc_req = false; 154 s->ddc_skip_finish = false; 155 s->ddc = false; 156 } 157 158 static void sii9022_realize(DeviceState *dev, Error **errp) 159 { 160 I2CBus *bus; 161 162 bus = I2C_BUS(qdev_get_parent_bus(dev)); 163 i2c_create_slave(bus, TYPE_I2CDDC, 0x50); 164 } 165 166 static void sii9022_class_init(ObjectClass *klass, void *data) 167 { 168 DeviceClass *dc = DEVICE_CLASS(klass); 169 I2CSlaveClass *k = I2C_SLAVE_CLASS(klass); 170 171 k->event = sii9022_event; 172 k->recv = sii9022_rx; 173 k->send = sii9022_tx; 174 dc->reset = sii9022_reset; 175 dc->realize = sii9022_realize; 176 dc->vmsd = &vmstate_sii9022; 177 } 178 179 static const TypeInfo sii9022_info = { 180 .name = TYPE_SII9022, 181 .parent = TYPE_I2C_SLAVE, 182 .instance_size = sizeof(sii9022_state), 183 .class_init = sii9022_class_init, 184 }; 185 186 static void sii9022_register_types(void) 187 { 188 type_register_static(&sii9022_info); 189 } 190 191 type_init(sii9022_register_types) 192