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Diffstat (limited to 'hw/i2c/arm_sbcon_i2c.c')
-rw-r--r--hw/i2c/arm_sbcon_i2c.c107
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)