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 typedef struct sii9022_state sii9022_state; 40 #define SII9022(obj) OBJECT_CHECK(sii9022_state, (obj), TYPE_SII9022) 41 42 struct sii9022_state { 43 I2CSlave parent_obj; 44 uint8_t ptr; 45 bool addr_byte; 46 bool ddc_req; 47 bool ddc_skip_finish; 48 bool ddc; 49 }; 50 51 static const VMStateDescription vmstate_sii9022 = { 52 .name = "sii9022", 53 .version_id = 1, 54 .minimum_version_id = 1, 55 .fields = (VMStateField[]) { 56 VMSTATE_I2C_SLAVE(parent_obj, sii9022_state), 57 VMSTATE_UINT8(ptr, sii9022_state), 58 VMSTATE_BOOL(addr_byte, sii9022_state), 59 VMSTATE_BOOL(ddc_req, sii9022_state), 60 VMSTATE_BOOL(ddc_skip_finish, sii9022_state), 61 VMSTATE_BOOL(ddc, sii9022_state), 62 VMSTATE_END_OF_LIST() 63 } 64 }; 65 66 static int sii9022_event(I2CSlave *i2c, enum i2c_event event) 67 { 68 sii9022_state *s = SII9022(i2c); 69 70 switch (event) { 71 case I2C_START_SEND: 72 s->addr_byte = true; 73 break; 74 case I2C_START_RECV: 75 break; 76 case I2C_FINISH: 77 break; 78 case I2C_NACK: 79 break; 80 } 81 82 return 0; 83 } 84 85 static uint8_t sii9022_rx(I2CSlave *i2c) 86 { 87 sii9022_state *s = SII9022(i2c); 88 uint8_t res = 0x00; 89 90 switch (s->ptr) { 91 case SII9022_SYS_CTRL_DATA: 92 if (s->ddc_req) { 93 /* Acknowledge DDC bus request */ 94 res = SII9022_SYS_CTRL_DDC_BUS_GRTD | SII9022_SYS_CTRL_DDC_BUS_REQ; 95 } 96 break; 97 case SII9022_REG_CHIPID: 98 res = 0xb0; 99 break; 100 case SII9022_INT_STATUS: 101 /* Something is cold-plugged in, no interrupts */ 102 res = SII9022_INT_STATUS_PLUGGED; 103 break; 104 default: 105 break; 106 } 107 108 trace_sii9022_read_reg(s->ptr, res); 109 s->ptr++; 110 111 return res; 112 } 113 114 static int sii9022_tx(I2CSlave *i2c, uint8_t data) 115 { 116 sii9022_state *s = SII9022(i2c); 117 118 if (s->addr_byte) { 119 s->ptr = data; 120 s->addr_byte = false; 121 return 0; 122 } 123 124 switch (s->ptr) { 125 case SII9022_SYS_CTRL_DATA: 126 if (data & SII9022_SYS_CTRL_DDC_BUS_REQ) { 127 s->ddc_req = true; 128 if (data & SII9022_SYS_CTRL_DDC_BUS_GRTD) { 129 s->ddc = true; 130 /* Skip this finish since we just switched to DDC */ 131 s->ddc_skip_finish = true; 132 trace_sii9022_switch_mode("DDC"); 133 } 134 } else { 135 s->ddc_req = false; 136 s->ddc = false; 137 trace_sii9022_switch_mode("normal"); 138 } 139 break; 140 default: 141 break; 142 } 143 144 trace_sii9022_write_reg(s->ptr, data); 145 s->ptr++; 146 147 return 0; 148 } 149 150 static void sii9022_reset(DeviceState *dev) 151 { 152 sii9022_state *s = SII9022(dev); 153 154 s->ptr = 0; 155 s->addr_byte = false; 156 s->ddc_req = false; 157 s->ddc_skip_finish = false; 158 s->ddc = false; 159 } 160 161 static void sii9022_realize(DeviceState *dev, Error **errp) 162 { 163 I2CBus *bus; 164 165 bus = I2C_BUS(qdev_get_parent_bus(dev)); 166 i2c_slave_create_simple(bus, TYPE_I2CDDC, 0x50); 167 } 168 169 static void sii9022_class_init(ObjectClass *klass, void *data) 170 { 171 DeviceClass *dc = DEVICE_CLASS(klass); 172 I2CSlaveClass *k = I2C_SLAVE_CLASS(klass); 173 174 k->event = sii9022_event; 175 k->recv = sii9022_rx; 176 k->send = sii9022_tx; 177 dc->reset = sii9022_reset; 178 dc->realize = sii9022_realize; 179 dc->vmsd = &vmstate_sii9022; 180 } 181 182 static const TypeInfo sii9022_info = { 183 .name = TYPE_SII9022, 184 .parent = TYPE_I2C_SLAVE, 185 .instance_size = sizeof(sii9022_state), 186 .class_init = sii9022_class_init, 187 }; 188 189 static void sii9022_register_types(void) 190 { 191 type_register_static(&sii9022_info); 192 } 193 194 type_init(sii9022_register_types) 195