i2c: Split smbus into parts

smbus.c and smbus.h had device side code, master side code, and
smbus.h has some smbus_eeprom.c definitions.  Split them into
separate files.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>

1 files changed, 236 insertions, 0 deletions

diff --git a/hw/i2c/smbus_slave.c b/hw/i2c/smbus_slave.c
new file mode 100644
index 0000000000..463fafe3c5
--- /dev/null
+++ b/hw/i2c/smbus_slave.c
@@ -0,0 +1,236 @@
+/*
+ * QEMU SMBus device emulation.
+ *
+ * This code is a helper for SMBus device emulation.  It implements an
+ * I2C device inteface and runs the SMBus protocol from the device
+ * point of view and maps those to simple calls to emulate.
+ *
+ * Copyright (c) 2007 CodeSourcery.
+ * Written by Paul Brook
+ *
+ * This code is licensed under the LGPL.
+ */
+
+/* TODO: Implement PEC.  */
+
+#include "qemu/osdep.h"
+#include "hw/hw.h"
+#include "hw/i2c/i2c.h"
+#include "hw/i2c/smbus_slave.h"
+
+//#define DEBUG_SMBUS 1
+
+#ifdef DEBUG_SMBUS
+#define DPRINTF(fmt, ...) \
+do { printf("smbus(%02x): " fmt , dev->i2c.address, ## __VA_ARGS__); } while (0)
+#define BADF(fmt, ...) \
+do { fprintf(stderr, "smbus: error: " fmt , ## __VA_ARGS__); exit(1);} while (0)
+#else
+#define DPRINTF(fmt, ...) do {} while(0)
+#define BADF(fmt, ...) \
+do { fprintf(stderr, "smbus: error: " fmt , ## __VA_ARGS__);} while (0)
+#endif
+
+enum {
+    SMBUS_IDLE,
+    SMBUS_WRITE_DATA,
+    SMBUS_RECV_BYTE,
+    SMBUS_READ_DATA,
+    SMBUS_DONE,
+    SMBUS_CONFUSED = -1
+};
+
+static void smbus_do_quick_cmd(SMBusDevice *dev, int recv)
+{
+    SMBusDeviceClass *sc = SMBUS_DEVICE_GET_CLASS(dev);
+
+    DPRINTF("Quick Command %d\n", recv);
+    if (sc->quick_cmd) {
+        sc->quick_cmd(dev, recv);
+    }
+}
+
+static void smbus_do_write(SMBusDevice *dev)
+{
+    SMBusDeviceClass *sc = SMBUS_DEVICE_GET_CLASS(dev);
+
+    if (dev->data_len == 0) {
+        smbus_do_quick_cmd(dev, 0);
+    } else if (dev->data_len == 1) {
+        DPRINTF("Send Byte\n");
+        if (sc->send_byte) {
+            sc->send_byte(dev, dev->data_buf[0]);
+        }
+    } else {
+        dev->command = dev->data_buf[0];
+        DPRINTF("Command %d len %d\n", dev->command, dev->data_len - 1);
+        if (sc->write_data) {
+            sc->write_data(dev, dev->command, dev->data_buf + 1,
+                           dev->data_len - 1);
+        }
+    }
+}
+
+static int smbus_i2c_event(I2CSlave *s, enum i2c_event event)
+{
+    SMBusDevice *dev = SMBUS_DEVICE(s);
+
+    switch (event) {
+    case I2C_START_SEND:
+        switch (dev->mode) {
+        case SMBUS_IDLE:
+            DPRINTF("Incoming data\n");
+            dev->mode = SMBUS_WRITE_DATA;
+            break;
+        default:
+            BADF("Unexpected send start condition in state %d\n", dev->mode);
+            dev->mode = SMBUS_CONFUSED;
+            break;
+        }
+        break;
+
+    case I2C_START_RECV:
+        switch (dev->mode) {
+        case SMBUS_IDLE:
+            DPRINTF("Read mode\n");
+            dev->mode = SMBUS_RECV_BYTE;
+            break;
+        case SMBUS_WRITE_DATA:
+            if (dev->data_len == 0) {
+                BADF("Read after write with no data\n");
+                dev->mode = SMBUS_CONFUSED;
+            } else {
+                if (dev->data_len > 1) {
+                    smbus_do_write(dev);
+                } else {
+                    dev->command = dev->data_buf[0];
+                    DPRINTF("%02x: Command %d\n", dev->i2c.address,
+                            dev->command);
+                }
+                DPRINTF("Read mode\n");
+                dev->data_len = 0;
+                dev->mode = SMBUS_READ_DATA;
+            }
+            break;
+        default:
+            BADF("Unexpected recv start condition in state %d\n", dev->mode);
+            dev->mode = SMBUS_CONFUSED;
+            break;
+        }
+        break;
+
+    case I2C_FINISH:
+        switch (dev->mode) {
+        case SMBUS_WRITE_DATA:
+            smbus_do_write(dev);
+            break;
+        case SMBUS_RECV_BYTE:
+            smbus_do_quick_cmd(dev, 1);
+            break;
+        case SMBUS_READ_DATA:
+            BADF("Unexpected stop during receive\n");
+            break;
+        default:
+            /* Nothing to do.  */
+            break;
+        }
+        dev->mode = SMBUS_IDLE;
+        dev->data_len = 0;
+        break;
+
+    case I2C_NACK:
+        switch (dev->mode) {
+        case SMBUS_DONE:
+            /* Nothing to do.  */
+            break;
+        case SMBUS_READ_DATA:
+            dev->mode = SMBUS_DONE;
+            break;
+        default:
+            BADF("Unexpected NACK in state %d\n", dev->mode);
+            dev->mode = SMBUS_CONFUSED;
+            break;
+        }
+    }
+
+    return 0;
+}
+
+static int smbus_i2c_recv(I2CSlave *s)
+{
+    SMBusDevice *dev = SMBUS_DEVICE(s);
+    SMBusDeviceClass *sc = SMBUS_DEVICE_GET_CLASS(dev);
+    int ret;
+
+    switch (dev->mode) {
+    case SMBUS_RECV_BYTE:
+        if (sc->receive_byte) {
+            ret = sc->receive_byte(dev);
+        } else {
+            ret = 0;
+        }
+        DPRINTF("Receive Byte %02x\n", ret);
+        dev->mode = SMBUS_DONE;
+        break;
+    case SMBUS_READ_DATA:
+        if (sc->read_data) {
+            ret = sc->read_data(dev, dev->command, dev->data_len);
+            dev->data_len++;
+        } else {
+            ret = 0;
+        }
+        DPRINTF("Read data %02x\n", ret);
+        break;
+    default:
+        BADF("Unexpected read in state %d\n", dev->mode);
+        dev->mode = SMBUS_CONFUSED;
+        ret = 0;
+        break;
+    }
+    return ret;
+}
+
+static int smbus_i2c_send(I2CSlave *s, uint8_t data)
+{
+    SMBusDevice *dev = SMBUS_DEVICE(s);
+
+    switch (dev->mode) {
+    case SMBUS_WRITE_DATA:
+        DPRINTF("Write data %02x\n", data);
+        if (dev->data_len >= sizeof(dev->data_buf)) {
+            BADF("Too many bytes sent\n");
+        } else {
+            dev->data_buf[dev->data_len++] = data;
+        }
+        break;
+    default:
+        BADF("Unexpected write in state %d\n", dev->mode);
+        break;
+    }
+    return 0;
+}
+
+static void smbus_device_class_init(ObjectClass *klass, void *data)
+{
+    I2CSlaveClass *sc = I2C_SLAVE_CLASS(klass);
+
+    sc->event = smbus_i2c_event;
+    sc->recv = smbus_i2c_recv;
+    sc->send = smbus_i2c_send;
+}
+
+static const TypeInfo smbus_device_type_info = {
+    .name = TYPE_SMBUS_DEVICE,
+    .parent = TYPE_I2C_SLAVE,
+    .instance_size = sizeof(SMBusDevice),
+    .abstract = true,
+    .class_size = sizeof(SMBusDeviceClass),
+    .class_init = smbus_device_class_init,
+};
+
+static void smbus_device_register_types(void)
+{
+    type_register_static(&smbus_device_type_info);
+}
+
+type_init(smbus_device_register_types)