diff options
Diffstat (limited to 'hw/i2c/arm_sbcon_i2c.c')
-rw-r--r-- | hw/i2c/arm_sbcon_i2c.c | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/hw/i2c/arm_sbcon_i2c.c b/hw/i2c/arm_sbcon_i2c.c new file mode 100644 index 0000000000..979ccbe0ed --- /dev/null +++ b/hw/i2c/arm_sbcon_i2c.c @@ -0,0 +1,107 @@ +/* + * ARM SBCon two-wire serial bus interface (I2C bitbang) + * a.k.a. ARM Versatile I2C controller + * + * Copyright (c) 2006-2007 CodeSourcery. + * Copyright (c) 2012 Oskar Andero <oskar.andero@gmail.com> + * + * This file is derived from hw/realview.c by Paul Brook + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + * + */ + +#include "qemu/osdep.h" +#include "hw/i2c/arm_sbcon_i2c.h" +#include "hw/registerfields.h" +#include "qemu/log.h" +#include "qemu/module.h" +#include "qom/object.h" + + +REG32(CONTROL_GET, 0) +REG32(CONTROL_SET, 0) +REG32(CONTROL_CLR, 4) + +#define SCL BIT(0) +#define SDA BIT(1) + +static uint64_t arm_sbcon_i2c_read(void *opaque, hwaddr offset, + unsigned size) +{ + ArmSbconI2CState *s = opaque; + + switch (offset) { + case A_CONTROL_SET: + return (s->out & 1) | (s->in << 1); + default: + qemu_log_mask(LOG_GUEST_ERROR, + "%s: Bad offset 0x%x\n", __func__, (int)offset); + return -1; + } +} + +static void arm_sbcon_i2c_write(void *opaque, hwaddr offset, + uint64_t value, unsigned size) +{ + ArmSbconI2CState *s = opaque; + + switch (offset) { + case A_CONTROL_SET: + s->out |= value & 3; + break; + case A_CONTROL_CLR: + s->out &= ~value; + break; + default: + qemu_log_mask(LOG_GUEST_ERROR, + "%s: Bad offset 0x%x\n", __func__, (int)offset); + } + bitbang_i2c_set(&s->bitbang, BITBANG_I2C_SCL, (s->out & SCL) != 0); + s->in = bitbang_i2c_set(&s->bitbang, BITBANG_I2C_SDA, (s->out & SDA) != 0); +} + +static const MemoryRegionOps arm_sbcon_i2c_ops = { + .read = arm_sbcon_i2c_read, + .write = arm_sbcon_i2c_write, + .endianness = DEVICE_NATIVE_ENDIAN, +}; + +static void arm_sbcon_i2c_init(Object *obj) +{ + DeviceState *dev = DEVICE(obj); + ArmSbconI2CState *s = ARM_SBCON_I2C(obj); + SysBusDevice *sbd = SYS_BUS_DEVICE(obj); + I2CBus *bus; + + bus = i2c_init_bus(dev, "i2c"); + bitbang_i2c_init(&s->bitbang, bus); + memory_region_init_io(&s->iomem, obj, &arm_sbcon_i2c_ops, s, + "arm_sbcon_i2c", 0x1000); + sysbus_init_mmio(sbd, &s->iomem); +} + +static const TypeInfo arm_sbcon_i2c_info = { + .name = TYPE_ARM_SBCON_I2C, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(ArmSbconI2CState), + .instance_init = arm_sbcon_i2c_init, +}; + +static void arm_sbcon_i2c_register_types(void) +{ + type_register_static(&arm_sbcon_i2c_info); +} + +type_init(arm_sbcon_i2c_register_types) |