[PATCH v3 08/13] hw/misc/auxbus: Explode READ_I2C / WRITE_I2C_MOT cases

["Philippe Mathieu-Daudé" <f4bug@amsat.org>]

To allow further simplifications in the following commits,
start copying WRITE_I2C code to the READ_I2C, and READ_I2C_MOT
to WRITE_I2C_MOT. No logical change.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 hw/misc/auxbus.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/hw/misc/auxbus.c b/hw/misc/auxbus.c
index 148b070ce4a..9cc9cf3be32 100644
--- a/hw/misc/auxbus.c
+++ b/hw/misc/auxbus.c
@@ -133,6 +133,26 @@ AUXReply aux_request(AUXBus *bus, AUXCommand cmd, uint32_t address,
      * Classic I2C transactions..
      */
     case READ_I2C:
+        is_write = cmd == READ_I2C ? false : true;
+        if (i2c_bus_busy(i2c_bus)) {
+            i2c_end_transfer(i2c_bus);
+        }
+
+        if (i2c_start_transfer(i2c_bus, address, !is_write)) {
+            ret = AUX_I2C_NACK;
+            break;
+        }
+
+        ret = AUX_I2C_ACK;
+        while (len > 0) {
+            if (i2c_send_recv(i2c_bus, data++, is_write) < 0) {
+                ret = AUX_I2C_NACK;
+                break;
+            }
+            len--;
+        }
+        i2c_end_transfer(i2c_bus);
+        break;
     case WRITE_I2C:
         is_write = cmd == READ_I2C ? false : true;
         if (i2c_bus_busy(i2c_bus)) {
@@ -163,6 +183,39 @@ AUXReply aux_request(AUXBus *bus, AUXCommand cmd, uint32_t address,
      *  - We changed the address.
      */
     case WRITE_I2C_MOT:
+        is_write = cmd == READ_I2C_MOT ? false : true;
+        ret = AUX_I2C_NACK;
+        if (!i2c_bus_busy(i2c_bus)) {
+            /*
+             * No transactions started..
+             */
+            if (i2c_start_transfer(i2c_bus, address, !is_write)) {
+                break;
+            }
+        } else if ((address != bus->last_i2c_address) ||
+                   (bus->last_transaction != cmd)) {
+            /*
+             * Transaction started but we need to restart..
+             */
+            i2c_end_transfer(i2c_bus);
+            if (i2c_start_transfer(i2c_bus, address, !is_write)) {
+                break;
+            }
+        }
+
+        bus->last_transaction = cmd;
+        bus->last_i2c_address = address;
+        while (len > 0) {
+            if (i2c_send_recv(i2c_bus, data++, is_write) < 0) {
+                i2c_end_transfer(i2c_bus);
+                break;
+            }
+            len--;
+        }
+        if (len == 0) {
+            ret = AUX_I2C_ACK;
+        }
+        break;
     case READ_I2C_MOT:
         is_write = cmd == READ_I2C_MOT ? false : true;
         ret = AUX_I2C_NACK;
-- 
2.31.1