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 #include "qom/object.h" 23 24 #define SII9022_SYS_CTRL_DATA 0x1a 25 #define SII9022_SYS_CTRL_PWR_DWN 0x10 26 #define SII9022_SYS_CTRL_AV_MUTE 0x08 27 #define SII9022_SYS_CTRL_DDC_BUS_REQ 0x04 28 #define SII9022_SYS_CTRL_DDC_BUS_GRTD 0x02 29 #define SII9022_SYS_CTRL_OUTPUT_MODE 0x01 30 #define SII9022_SYS_CTRL_OUTPUT_HDMI 1 31 #define SII9022_SYS_CTRL_OUTPUT_DVI 0 32 #define SII9022_REG_CHIPID 0x1b 33 #define SII9022_INT_ENABLE 0x3c 34 #define SII9022_INT_STATUS 0x3d 35 #define SII9022_INT_STATUS_HOTPLUG 0x01; 36 #define SII9022_INT_STATUS_PLUGGED 0x04; 37 38 #define TYPE_SII9022 "sii9022" 39 OBJECT_DECLARE_SIMPLE_TYPE(sii9022_state, SII9022) 40 41 struct sii9022_state { 42 I2CSlave parent_obj; 43 uint8_t ptr; 44 bool addr_byte; 45 bool ddc_req; 46 bool ddc_skip_finish; 47 bool ddc; 48 }; 49 50 static const VMStateDescription vmstate_sii9022 = { 51 .name = "sii9022", 52 .version_id = 1, 53 .minimum_version_id = 1, 54 .fields = (VMStateField[]) { 55 VMSTATE_I2C_SLAVE(parent_obj, sii9022_state), 56 VMSTATE_UINT8(ptr, sii9022_state), 57 VMSTATE_BOOL(addr_byte, sii9022_state), 58 VMSTATE_BOOL(ddc_req, sii9022_state), 59 VMSTATE_BOOL(ddc_skip_finish, sii9022_state), 60 VMSTATE_BOOL(ddc, sii9022_state), 61 VMSTATE_END_OF_LIST() 62 } 63 }; 64 65 static int sii9022_event(I2CSlave *i2c, enum i2c_event event) 66 { 67 sii9022_state *s = SII9022(i2c); 68 69 switch (event) { 70 case I2C_START_SEND: 71 s->addr_byte = true; 72 break; 73 case I2C_START_RECV: 74 break; 75 case I2C_FINISH: 76 break; 77 case I2C_NACK: 78 break; 79 } 80 81 return 0; 82 } 83 84 static uint8_t sii9022_rx(I2CSlave *i2c) 85 { 86 sii9022_state *s = SII9022(i2c); 87 uint8_t res = 0x00; 88 89 switch (s->ptr) { 90 case SII9022_SYS_CTRL_DATA: 91 if (s->ddc_req) { 92 /* Acknowledge DDC bus request */ 93 res = SII9022_SYS_CTRL_DDC_BUS_GRTD | SII9022_SYS_CTRL_DDC_BUS_REQ; 94 } 95 break; 96 case SII9022_REG_CHIPID: 97 res = 0xb0; 98 break; 99 case SII9022_INT_STATUS: 100 /* Something is cold-plugged in, no interrupts */ 101 res = SII9022_INT_STATUS_PLUGGED; 102 break; 103 default: 104 break; 105 } 106 107 trace_sii9022_read_reg(s->ptr, res); 108 s->ptr++; 109 110 return res; 111 } 112 113 static int sii9022_tx(I2CSlave *i2c, uint8_t data) 114 { 115 sii9022_state *s = SII9022(i2c); 116 117 if (s->addr_byte) { 118 s->ptr = data; 119 s->addr_byte = false; 120 return 0; 121 } 122 123 switch (s->ptr) { 124 case SII9022_SYS_CTRL_DATA: 125 if (data & SII9022_SYS_CTRL_DDC_BUS_REQ) { 126 s->ddc_req = true; 127 if (data & SII9022_SYS_CTRL_DDC_BUS_GRTD) { 128 s->ddc = true; 129 /* Skip this finish since we just switched to DDC */ 130 s->ddc_skip_finish = true; 131 trace_sii9022_switch_mode("DDC"); 132 } 133 } else { 134 s->ddc_req = false; 135 s->ddc = false; 136 trace_sii9022_switch_mode("normal"); 137 } 138 break; 139 default: 140 break; 141 } 142 143 trace_sii9022_write_reg(s->ptr, data); 144 s->ptr++; 145 146 return 0; 147 } 148 149 static void sii9022_reset(DeviceState *dev) 150 { 151 sii9022_state *s = SII9022(dev); 152 153 s->ptr = 0; 154 s->addr_byte = false; 155 s->ddc_req = false; 156 s->ddc_skip_finish = false; 157 s->ddc = false; 158 } 159 160 static void sii9022_realize(DeviceState *dev, Error **errp) 161 { 162 I2CBus *bus; 163 164 bus = I2C_BUS(qdev_get_parent_bus(dev)); 165 i2c_slave_create_simple(bus, TYPE_I2CDDC, 0x50); 166 } 167 168 static void sii9022_class_init(ObjectClass *klass, void *data) 169 { 170 DeviceClass *dc = DEVICE_CLASS(klass); 171 I2CSlaveClass *k = I2C_SLAVE_CLASS(klass); 172 173 k->event = sii9022_event; 174 k->recv = sii9022_rx; 175 k->send = sii9022_tx; 176 dc->reset = sii9022_reset; 177 dc->realize = sii9022_realize; 178 dc->vmsd = &vmstate_sii9022; 179 } 180 181 static const TypeInfo sii9022_info = { 182 .name = TYPE_SII9022, 183 .parent = TYPE_I2C_SLAVE, 184 .instance_size = sizeof(sii9022_state), 185 .class_init = sii9022_class_init, 186 }; 187 188 static void sii9022_register_types(void) 189 { 190 type_register_static(&sii9022_info); 191 } 192 193 type_init(sii9022_register_types) 194