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