root / hw / i2c / versatile_i2c.c @ 49ab747f
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/*
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* ARM Versatile I2C controller
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*
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* Copyright (c) 2006-2007 CodeSourcery.
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* Copyright (c) 2012 Oskar Andero <oskar.andero@gmail.com>
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*
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* This file is derived from hw/realview.c by Paul Brook
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, see <http://www.gnu.org/licenses/>.
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*
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*/
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#include "hw/sysbus.h" |
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#include "hw/bitbang_i2c.h" |
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typedef struct { |
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SysBusDevice busdev; |
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MemoryRegion iomem; |
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bitbang_i2c_interface *bitbang; |
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int out;
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int in;
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} VersatileI2CState; |
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static uint64_t versatile_i2c_read(void *opaque, hwaddr offset, |
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unsigned size)
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{ |
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VersatileI2CState *s = (VersatileI2CState *)opaque; |
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if (offset == 0) { |
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return (s->out & 1) | (s->in << 1); |
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} else {
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qemu_log_mask(LOG_GUEST_ERROR, |
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"%s: Bad offset 0x%x\n", __func__, (int)offset); |
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return -1; |
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} |
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} |
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static void versatile_i2c_write(void *opaque, hwaddr offset, |
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uint64_t value, unsigned size)
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{ |
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VersatileI2CState *s = (VersatileI2CState *)opaque; |
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switch (offset) {
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case 0: |
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s->out |= value & 3;
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break;
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case 4: |
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s->out &= ~value; |
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break;
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default:
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qemu_log_mask(LOG_GUEST_ERROR, |
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"%s: Bad offset 0x%x\n", __func__, (int)offset); |
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} |
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bitbang_i2c_set(s->bitbang, BITBANG_I2C_SCL, (s->out & 1) != 0); |
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s->in = bitbang_i2c_set(s->bitbang, BITBANG_I2C_SDA, (s->out & 2) != 0); |
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} |
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static const MemoryRegionOps versatile_i2c_ops = { |
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.read = versatile_i2c_read, |
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.write = versatile_i2c_write, |
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.endianness = DEVICE_NATIVE_ENDIAN, |
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}; |
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static int versatile_i2c_init(SysBusDevice *dev) |
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{ |
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VersatileI2CState *s = FROM_SYSBUS(VersatileI2CState, dev); |
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i2c_bus *bus; |
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bus = i2c_init_bus(&dev->qdev, "i2c");
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s->bitbang = bitbang_i2c_init(bus); |
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memory_region_init_io(&s->iomem, &versatile_i2c_ops, s, |
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"versatile_i2c", 0x1000); |
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sysbus_init_mmio(dev, &s->iomem); |
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return 0; |
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} |
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static void versatile_i2c_class_init(ObjectClass *klass, void *data) |
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{ |
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SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass); |
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k->init = versatile_i2c_init; |
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} |
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static const TypeInfo versatile_i2c_info = { |
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.name = "versatile_i2c",
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.parent = TYPE_SYS_BUS_DEVICE, |
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.instance_size = sizeof(VersatileI2CState),
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.class_init = versatile_i2c_class_init, |
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}; |
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static void versatile_i2c_register_types(void) |
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{ |
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type_register_static(&versatile_i2c_info); |
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} |
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type_init(versatile_i2c_register_types) |