1 /* 2 * QEMU Synchronous Serial Interface support 3 * 4 * Copyright (c) 2009 CodeSourcery. 5 * Copyright (c) 2012 Peter A.G. Crosthwaite (peter.crosthwaite@petalogix.com) 6 * Copyright (c) 2012 PetaLogix Pty Ltd. 7 * Written by Paul Brook 8 * 9 * This code is licensed under the GNU GPL v2. 10 * 11 * Contributions after 2012-01-13 are licensed under the terms of the 12 * GNU GPL, version 2 or (at your option) any later version. 13 */ 14 15 #include "qemu/osdep.h" 16 #include "hw/ssi/ssi.h" 17 #include "migration/vmstate.h" 18 #include "qemu/module.h" 19 20 struct SSIBus { 21 BusState parent_obj; 22 }; 23 24 #define TYPE_SSI_BUS "SSI" 25 #define SSI_BUS(obj) OBJECT_CHECK(SSIBus, (obj), TYPE_SSI_BUS) 26 27 static const TypeInfo ssi_bus_info = { 28 .name = TYPE_SSI_BUS, 29 .parent = TYPE_BUS, 30 .instance_size = sizeof(SSIBus), 31 }; 32 33 static void ssi_cs_default(void *opaque, int n, int level) 34 { 35 SSISlave *s = SSI_SLAVE(opaque); 36 bool cs = !!level; 37 assert(n == 0); 38 if (s->cs != cs) { 39 SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(s); 40 if (ssc->set_cs) { 41 ssc->set_cs(s, cs); 42 } 43 } 44 s->cs = cs; 45 } 46 47 static uint32_t ssi_transfer_raw_default(SSISlave *dev, uint32_t val) 48 { 49 SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(dev); 50 51 if ((dev->cs && ssc->cs_polarity == SSI_CS_HIGH) || 52 (!dev->cs && ssc->cs_polarity == SSI_CS_LOW) || 53 ssc->cs_polarity == SSI_CS_NONE) { 54 return ssc->transfer(dev, val); 55 } 56 return 0; 57 } 58 59 static void ssi_slave_realize(DeviceState *dev, Error **errp) 60 { 61 SSISlave *s = SSI_SLAVE(dev); 62 SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(s); 63 64 if (ssc->transfer_raw == ssi_transfer_raw_default && 65 ssc->cs_polarity != SSI_CS_NONE) { 66 qdev_init_gpio_in_named(dev, ssi_cs_default, SSI_GPIO_CS, 1); 67 } 68 69 ssc->realize(s, errp); 70 } 71 72 static void ssi_slave_class_init(ObjectClass *klass, void *data) 73 { 74 SSISlaveClass *ssc = SSI_SLAVE_CLASS(klass); 75 DeviceClass *dc = DEVICE_CLASS(klass); 76 77 dc->realize = ssi_slave_realize; 78 dc->bus_type = TYPE_SSI_BUS; 79 if (!ssc->transfer_raw) { 80 ssc->transfer_raw = ssi_transfer_raw_default; 81 } 82 } 83 84 static const TypeInfo ssi_slave_info = { 85 .name = TYPE_SSI_SLAVE, 86 .parent = TYPE_DEVICE, 87 .class_init = ssi_slave_class_init, 88 .class_size = sizeof(SSISlaveClass), 89 .abstract = true, 90 }; 91 92 DeviceState *ssi_create_slave_no_init(SSIBus *bus, const char *name) 93 { 94 return qdev_create(BUS(bus), name); 95 } 96 97 DeviceState *ssi_create_slave(SSIBus *bus, const char *name) 98 { 99 DeviceState *dev = ssi_create_slave_no_init(bus, name); 100 101 qdev_init_nofail(dev); 102 return dev; 103 } 104 105 SSIBus *ssi_create_bus(DeviceState *parent, const char *name) 106 { 107 BusState *bus; 108 bus = qbus_create(TYPE_SSI_BUS, parent, name); 109 return SSI_BUS(bus); 110 } 111 112 uint32_t ssi_transfer(SSIBus *bus, uint32_t val) 113 { 114 BusState *b = BUS(bus); 115 BusChild *kid; 116 SSISlaveClass *ssc; 117 uint32_t r = 0; 118 119 QTAILQ_FOREACH(kid, &b->children, sibling) { 120 SSISlave *slave = SSI_SLAVE(kid->child); 121 ssc = SSI_SLAVE_GET_CLASS(slave); 122 r |= ssc->transfer_raw(slave, val); 123 } 124 125 return r; 126 } 127 128 const VMStateDescription vmstate_ssi_slave = { 129 .name = "SSISlave", 130 .version_id = 1, 131 .minimum_version_id = 1, 132 .fields = (VMStateField[]) { 133 VMSTATE_BOOL(cs, SSISlave), 134 VMSTATE_END_OF_LIST() 135 } 136 }; 137 138 static void ssi_slave_register_types(void) 139 { 140 type_register_static(&ssi_bus_info); 141 type_register_static(&ssi_slave_info); 142 } 143 144 type_init(ssi_slave_register_types) 145 146 typedef struct SSIAutoConnectArg { 147 qemu_irq **cs_linep; 148 SSIBus *bus; 149 } SSIAutoConnectArg; 150 151 static int ssi_auto_connect_slave(Object *child, void *opaque) 152 { 153 SSIAutoConnectArg *arg = opaque; 154 SSISlave *dev = (SSISlave *)object_dynamic_cast(child, TYPE_SSI_SLAVE); 155 qemu_irq cs_line; 156 157 if (!dev) { 158 return 0; 159 } 160 161 cs_line = qdev_get_gpio_in_named(DEVICE(dev), SSI_GPIO_CS, 0); 162 qdev_set_parent_bus(DEVICE(dev), BUS(arg->bus)); 163 **arg->cs_linep = cs_line; 164 (*arg->cs_linep)++; 165 return 0; 166 } 167 168 void ssi_auto_connect_slaves(DeviceState *parent, qemu_irq *cs_line, 169 SSIBus *bus) 170 { 171 SSIAutoConnectArg arg = { 172 .cs_linep = &cs_line, 173 .bus = bus 174 }; 175 176 object_child_foreach(OBJECT(parent), ssi_auto_connect_slave, &arg); 177 } 178