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/module.h" 18 #include "hw/i2c/i2c.h" 19 #include "migration/vmstate.h" 20 #include "hw/display/i2c-ddc.h" 21 #include "trace.h" 22 23 #define SII9022_SYS_CTRL_DATA 0x1a 24 #define SII9022_SYS_CTRL_PWR_DWN 0x10 25 #define SII9022_SYS_CTRL_AV_MUTE 0x08 26 #define SII9022_SYS_CTRL_DDC_BUS_REQ 0x04 27 #define SII9022_SYS_CTRL_DDC_BUS_GRTD 0x02 28 #define SII9022_SYS_CTRL_OUTPUT_MODE 0x01 29 #define SII9022_SYS_CTRL_OUTPUT_HDMI 1 30 #define SII9022_SYS_CTRL_OUTPUT_DVI 0 31 #define SII9022_REG_CHIPID 0x1b 32 #define SII9022_INT_ENABLE 0x3c 33 #define SII9022_INT_STATUS 0x3d 34 #define SII9022_INT_STATUS_HOTPLUG 0x01; 35 #define SII9022_INT_STATUS_PLUGGED 0x04; 36 37 #define TYPE_SII9022 "sii9022" 38 #define SII9022(obj) OBJECT_CHECK(sii9022_state, (obj), TYPE_SII9022) 39 40 typedef struct sii9022_state { 41 I2CSlave parent_obj; 42 uint8_t ptr; 43 bool addr_byte; 44 bool ddc_req; 45 bool ddc_skip_finish; 46 bool ddc; 47 } sii9022_state; 48 49 static const VMStateDescription vmstate_sii9022 = { 50 .name = "sii9022", 51 .version_id = 1, 52 .minimum_version_id = 1, 53 .fields = (VMStateField[]) { 54 VMSTATE_I2C_SLAVE(parent_obj, sii9022_state), 55 VMSTATE_UINT8(ptr, sii9022_state), 56 VMSTATE_BOOL(addr_byte, sii9022_state), 57 VMSTATE_BOOL(ddc_req, sii9022_state), 58 VMSTATE_BOOL(ddc_skip_finish, sii9022_state), 59 VMSTATE_BOOL(ddc, sii9022_state), 60 VMSTATE_END_OF_LIST() 61 } 62 }; 63 64 static int sii9022_event(I2CSlave *i2c, enum i2c_event event) 65 { 66 sii9022_state *s = SII9022(i2c); 67 68 switch (event) { 69 case I2C_START_SEND: 70 s->addr_byte = true; 71 break; 72 case I2C_START_RECV: 73 break; 74 case I2C_FINISH: 75 break; 76 case I2C_NACK: 77 break; 78 } 79 80 return 0; 81 } 82 83 static uint8_t sii9022_rx(I2CSlave *i2c) 84 { 85 sii9022_state *s = SII9022(i2c); 86 uint8_t res = 0x00; 87 88 switch (s->ptr) { 89 case SII9022_SYS_CTRL_DATA: 90 if (s->ddc_req) { 91 /* Acknowledge DDC bus request */ 92 res = SII9022_SYS_CTRL_DDC_BUS_GRTD | SII9022_SYS_CTRL_DDC_BUS_REQ; 93 } 94 break; 95 case SII9022_REG_CHIPID: 96 res = 0xb0; 97 break; 98 case SII9022_INT_STATUS: 99 /* Something is cold-plugged in, no interrupts */ 100 res = SII9022_INT_STATUS_PLUGGED; 101 break; 102 default: 103 break; 104 } 105 106 trace_sii9022_read_reg(s->ptr, res); 107 s->ptr++; 108 109 return res; 110 } 111 112 static int sii9022_tx(I2CSlave *i2c, uint8_t data) 113 { 114 sii9022_state *s = SII9022(i2c); 115 116 if (s->addr_byte) { 117 s->ptr = data; 118 s->addr_byte = false; 119 return 0; 120 } 121 122 switch (s->ptr) { 123 case SII9022_SYS_CTRL_DATA: 124 if (data & SII9022_SYS_CTRL_DDC_BUS_REQ) { 125 s->ddc_req = true; 126 if (data & SII9022_SYS_CTRL_DDC_BUS_GRTD) { 127 s->ddc = true; 128 /* Skip this finish since we just switched to DDC */ 129 s->ddc_skip_finish = true; 130 trace_sii9022_switch_mode("DDC"); 131 } 132 } else { 133 s->ddc_req = false; 134 s->ddc = false; 135 trace_sii9022_switch_mode("normal"); 136 } 137 break; 138 default: 139 break; 140 } 141 142 trace_sii9022_write_reg(s->ptr, data); 143 s->ptr++; 144 145 return 0; 146 } 147 148 static void sii9022_reset(DeviceState *dev) 149 { 150 sii9022_state *s = SII9022(dev); 151 152 s->ptr = 0; 153 s->addr_byte = false; 154 s->ddc_req = false; 155 s->ddc_skip_finish = false; 156 s->ddc = false; 157 } 158 159 static void sii9022_realize(DeviceState *dev, Error **errp) 160 { 161 I2CBus *bus; 162 163 bus = I2C_BUS(qdev_get_parent_bus(dev)); 164 i2c_create_slave(bus, TYPE_I2CDDC, 0x50); 165 } 166 167 static void sii9022_class_init(ObjectClass *klass, void *data) 168 { 169 DeviceClass *dc = DEVICE_CLASS(klass); 170 I2CSlaveClass *k = I2C_SLAVE_CLASS(klass); 171 172 k->event = sii9022_event; 173 k->recv = sii9022_rx; 174 k->send = sii9022_tx; 175 dc->reset = sii9022_reset; 176 dc->realize = sii9022_realize; 177 dc->vmsd = &vmstate_sii9022; 178 } 179 180 static const TypeInfo sii9022_info = { 181 .name = TYPE_SII9022, 182 .parent = TYPE_I2C_SLAVE, 183 .instance_size = sizeof(sii9022_state), 184 .class_init = sii9022_class_init, 185 }; 186 187 static void sii9022_register_types(void) 188 { 189 type_register_static(&sii9022_info); 190 } 191 192 type_init(sii9022_register_types) 193