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 #include "qapi/error.h" 20 #include "qom/object.h" 21 22 struct SSIBus { 23 BusState parent_obj; 24 }; 25 26 #define TYPE_SSI_BUS "SSI" 27 DECLARE_INSTANCE_CHECKER(SSIBus, SSI_BUS, 28 TYPE_SSI_BUS) 29 30 static const TypeInfo ssi_bus_info = { 31 .name = TYPE_SSI_BUS, 32 .parent = TYPE_BUS, 33 .instance_size = sizeof(SSIBus), 34 }; 35 36 static void ssi_cs_default(void *opaque, int n, int level) 37 { 38 SSISlave *s = SSI_SLAVE(opaque); 39 bool cs = !!level; 40 assert(n == 0); 41 if (s->cs != cs) { 42 SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(s); 43 if (ssc->set_cs) { 44 ssc->set_cs(s, cs); 45 } 46 } 47 s->cs = cs; 48 } 49 50 static uint32_t ssi_transfer_raw_default(SSISlave *dev, uint32_t val) 51 { 52 SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(dev); 53 54 if ((dev->cs && ssc->cs_polarity == SSI_CS_HIGH) || 55 (!dev->cs && ssc->cs_polarity == SSI_CS_LOW) || 56 ssc->cs_polarity == SSI_CS_NONE) { 57 return ssc->transfer(dev, val); 58 } 59 return 0; 60 } 61 62 static void ssi_slave_realize(DeviceState *dev, Error **errp) 63 { 64 SSISlave *s = SSI_SLAVE(dev); 65 SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(s); 66 67 if (ssc->transfer_raw == ssi_transfer_raw_default && 68 ssc->cs_polarity != SSI_CS_NONE) { 69 qdev_init_gpio_in_named(dev, ssi_cs_default, SSI_GPIO_CS, 1); 70 } 71 72 ssc->realize(s, errp); 73 } 74 75 static void ssi_slave_class_init(ObjectClass *klass, void *data) 76 { 77 SSISlaveClass *ssc = SSI_SLAVE_CLASS(klass); 78 DeviceClass *dc = DEVICE_CLASS(klass); 79 80 dc->realize = ssi_slave_realize; 81 dc->bus_type = TYPE_SSI_BUS; 82 if (!ssc->transfer_raw) { 83 ssc->transfer_raw = ssi_transfer_raw_default; 84 } 85 } 86 87 static const TypeInfo ssi_slave_info = { 88 .name = TYPE_SSI_SLAVE, 89 .parent = TYPE_DEVICE, 90 .class_init = ssi_slave_class_init, 91 .class_size = sizeof(SSISlaveClass), 92 .abstract = true, 93 }; 94 95 bool ssi_realize_and_unref(DeviceState *dev, SSIBus *bus, Error **errp) 96 { 97 return qdev_realize_and_unref(dev, &bus->parent_obj, errp); 98 } 99 100 DeviceState *ssi_create_slave(SSIBus *bus, const char *name) 101 { 102 DeviceState *dev = qdev_new(name); 103 104 ssi_realize_and_unref(dev, bus, &error_fatal); 105 return dev; 106 } 107 108 SSIBus *ssi_create_bus(DeviceState *parent, const char *name) 109 { 110 BusState *bus; 111 bus = qbus_create(TYPE_SSI_BUS, parent, name); 112 return SSI_BUS(bus); 113 } 114 115 uint32_t ssi_transfer(SSIBus *bus, uint32_t val) 116 { 117 BusState *b = BUS(bus); 118 BusChild *kid; 119 SSISlaveClass *ssc; 120 uint32_t r = 0; 121 122 QTAILQ_FOREACH(kid, &b->children, sibling) { 123 SSISlave *slave = SSI_SLAVE(kid->child); 124 ssc = SSI_SLAVE_GET_CLASS(slave); 125 r |= ssc->transfer_raw(slave, val); 126 } 127 128 return r; 129 } 130 131 const VMStateDescription vmstate_ssi_slave = { 132 .name = "SSISlave", 133 .version_id = 1, 134 .minimum_version_id = 1, 135 .fields = (VMStateField[]) { 136 VMSTATE_BOOL(cs, SSISlave), 137 VMSTATE_END_OF_LIST() 138 } 139 }; 140 141 static void ssi_slave_register_types(void) 142 { 143 type_register_static(&ssi_bus_info); 144 type_register_static(&ssi_slave_info); 145 } 146 147 type_init(ssi_slave_register_types) 148