[PATCH] i2c: Match parameters of i2c_start_transfer and i2c_send_recv

[BALATON Zoltan <balaton@eik.bme.hu>]

These functions have a parameter that decides the direction of
transfer but totally confusingly they don't match but inverted sense.
To avoid frequent mistakes when using these functions change
i2c_send_recv to match i2c_start_transfer. Also use bool in
i2c_start_transfer instead of int to match i2c_send_recv.

Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
---
Looks like hw/misc/auxbus.c already got this wrong and calls both
i2c_start_transfer and i2c_send_recv with same is_write parameter.
Although the name of the is_write variable suggest this may need to be
inverted I'm not sure what that value actially means and which usage
was correct so I did not touch it. Someone knowing this device might
want to review and fix it.

 hw/display/sm501.c   |  2 +-
 hw/i2c/core.c        | 34 +++++++++++++++++-----------------
 hw/i2c/ppc4xx_i2c.c  |  2 +-
 include/hw/i2c/i2c.h |  4 ++--
 4 files changed, 21 insertions(+), 21 deletions(-)

diff --git a/hw/display/sm501.c b/hw/display/sm501.c
index 2db347dcbc..ccd0a6e376 100644
--- a/hw/display/sm501.c
+++ b/hw/display/sm501.c
@@ -1034,7 +1034,7 @@ static void sm501_i2c_write(void *opaque, hwaddr addr, uint64_t value,
                     int i;
                     for (i = 0; i <= s->i2c_byte_count; i++) {
                         res = i2c_send_recv(s->i2c_bus, &s->i2c_data[i],
-                                            !(s->i2c_addr & 1));
+                                            s->i2c_addr & 1);
                         if (res) {
                             s->i2c_status |= SM501_I2C_STATUS_ERROR;
                             return;
diff --git a/hw/i2c/core.c b/hw/i2c/core.c
index 1aac457a2a..c9d01df427 100644
--- a/hw/i2c/core.c
+++ b/hw/i2c/core.c
@@ -91,7 +91,7 @@ int i2c_bus_busy(I2CBus *bus)
  * without releasing the bus.  If that fails, the bus is still
  * in a transaction.
  */
-int i2c_start_transfer(I2CBus *bus, uint8_t address, int recv)
+int i2c_start_transfer(I2CBus *bus, uint8_t address, bool recv)
 {
     BusChild *kid;
     I2CSlaveClass *sc;
@@ -175,26 +175,14 @@ void i2c_end_transfer(I2CBus *bus)
     bus->broadcast = false;
 }
 
-int i2c_send_recv(I2CBus *bus, uint8_t *data, bool send)
+int i2c_send_recv(I2CBus *bus, uint8_t *data, bool recv)
 {
     I2CSlaveClass *sc;
     I2CSlave *s;
     I2CNode *node;
     int ret = 0;
 
-    if (send) {
-        QLIST_FOREACH(node, &bus->current_devs, next) {
-            s = node->elt;
-            sc = I2C_SLAVE_GET_CLASS(s);
-            if (sc->send) {
-                trace_i2c_send(s->address, *data);
-                ret = ret || sc->send(s, *data);
-            } else {
-                ret = -1;
-            }
-        }
-        return ret ? -1 : 0;
-    } else {
+    if (recv) {
         ret = 0xff;
         if (!QLIST_EMPTY(&bus->current_devs) && !bus->broadcast) {
             sc = I2C_SLAVE_GET_CLASS(QLIST_FIRST(&bus->current_devs)->elt);
@@ -206,19 +194,31 @@ int i2c_send_recv(I2CBus *bus, uint8_t *data, bool send)
         }
         *data = ret;
         return 0;
+    } else {
+        QLIST_FOREACH(node, &bus->current_devs, next) {
+            s = node->elt;
+            sc = I2C_SLAVE_GET_CLASS(s);
+            if (sc->send) {
+                trace_i2c_send(s->address, *data);
+                ret = ret || sc->send(s, *data);
+            } else {
+                ret = -1;
+            }
+        }
+        return ret ? -1 : 0;
     }
 }
 
 int i2c_send(I2CBus *bus, uint8_t data)
 {
-    return i2c_send_recv(bus, &data, true);
+    return i2c_send_recv(bus, &data, false);
 }
 
 uint8_t i2c_recv(I2CBus *bus)
 {
     uint8_t data = 0xff;
 
-    i2c_send_recv(bus, &data, false);
+    i2c_send_recv(bus, &data, true);
     return data;
 }
 
diff --git a/hw/i2c/ppc4xx_i2c.c b/hw/i2c/ppc4xx_i2c.c
index c0a8e04567..d3899203a4 100644
--- a/hw/i2c/ppc4xx_i2c.c
+++ b/hw/i2c/ppc4xx_i2c.c
@@ -239,7 +239,7 @@ static void ppc4xx_i2c_writeb(void *opaque, hwaddr addr, uint64_t value,
                     }
                 }
                 if (!(i2c->sts & IIC_STS_ERR) &&
-                    i2c_send_recv(i2c->bus, &i2c->mdata[i], !recv)) {
+                    i2c_send_recv(i2c->bus, &i2c->mdata[i], recv)) {
                     i2c->sts |= IIC_STS_ERR;
                     i2c->extsts |= IIC_EXTSTS_XFRA;
                     break;
diff --git a/include/hw/i2c/i2c.h b/include/hw/i2c/i2c.h
index 4117211565..a09ab9230b 100644
--- a/include/hw/i2c/i2c.h
+++ b/include/hw/i2c/i2c.h
@@ -72,10 +72,10 @@ struct I2CBus {
 I2CBus *i2c_init_bus(DeviceState *parent, const char *name);
 void i2c_set_slave_address(I2CSlave *dev, uint8_t address);
 int i2c_bus_busy(I2CBus *bus);
-int i2c_start_transfer(I2CBus *bus, uint8_t address, int recv);
+int i2c_start_transfer(I2CBus *bus, uint8_t address, bool recv);
 void i2c_end_transfer(I2CBus *bus);
 void i2c_nack(I2CBus *bus);
-int i2c_send_recv(I2CBus *bus, uint8_t *data, bool send);
+int i2c_send_recv(I2CBus *bus, uint8_t *data, bool recv);
 int i2c_send(I2CBus *bus, uint8_t data);
 uint8_t i2c_recv(I2CBus *bus);
 
-- 
2.21.3