mei: bus: use ssize_t as the return type for send and receive

Mei bus receive and send function may return either number
of transmitted bytes or errno.  It is better to use ssize_t
type for that purpose that mixing size_t with int.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/mei/bus.c

@@ -224,13 +224,13 @@ void mei_cl_driver_unregister(struct mei_cl_driver *driver)
 }
 EXPORT_SYMBOL_GPL(mei_cl_driver_unregister);
 
-static int ___mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
+static ssize_t ___mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
 			bool blocking)
 {
 	struct mei_device *dev;
 	struct mei_me_client *me_cl;
 	struct mei_cl_cb *cb;
-	int rets;
+	ssize_t rets;
 
 	if (WARN_ON(!cl || !cl->dev))
 		return -ENODEV;
@@ -271,12 +271,12 @@ static int ___mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
 	return rets;
 }
 
-int __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
+ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
 {
 	struct mei_device *dev;
 	struct mei_cl_cb *cb;
 	size_t r_length;
-	int err;
+	ssize_t rets;
 
 	if (WARN_ON(!cl || !cl->dev))
 		return -ENODEV;
@@ -286,11 +286,9 @@ int __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
 	mutex_lock(&dev->device_lock);
 
 	if (!cl->read_cb) {
-		err = mei_cl_read_start(cl, length);
-		if (err < 0) {
-			mutex_unlock(&dev->device_lock);
-			return err;
-		}
+		rets = mei_cl_read_start(cl, length);
+		if (rets < 0)
+			goto out;
 	}
 
 	if (cl->reading_state != MEI_READ_COMPLETE &&
@@ -313,13 +311,13 @@ int __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
 	cb = cl->read_cb;
 
 	if (cl->reading_state != MEI_READ_COMPLETE) {
-		r_length = 0;
+		rets = 0;
 		goto out;
 	}
 
 	r_length = min_t(size_t, length, cb->buf_idx);
-
 	memcpy(buf, cb->response_buffer.data, r_length);
+	rets = r_length;
 
 	mei_io_cb_free(cb);
 	cl->reading_state = MEI_IDLE;
@@ -328,20 +326,20 @@ int __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
 out:
 	mutex_unlock(&dev->device_lock);
 
-	return r_length;
+	return rets;
 }
 
-inline int __mei_cl_async_send(struct mei_cl *cl, u8 *buf, size_t length)
+inline ssize_t __mei_cl_async_send(struct mei_cl *cl, u8 *buf, size_t length)
 {
 	return ___mei_cl_send(cl, buf, length, 0);
 }
 
-inline int __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length)
+inline ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length)
 {
 	return ___mei_cl_send(cl, buf, length, 1);
 }
 
-int mei_cl_send(struct mei_cl_device *device, u8 *buf, size_t length)
+ssize_t mei_cl_send(struct mei_cl_device *device, u8 *buf, size_t length)
 {
 	struct mei_cl *cl = device->cl;
 
@@ -355,7 +353,7 @@ int mei_cl_send(struct mei_cl_device *device, u8 *buf, size_t length)
 }
 EXPORT_SYMBOL_GPL(mei_cl_send);
 
-int mei_cl_recv(struct mei_cl_device *device, u8 *buf, size_t length)
+ssize_t mei_cl_recv(struct mei_cl_device *device, u8 *buf, size_t length)
 {
 	struct mei_cl *cl =  device->cl;
 

drivers/misc/mei/mei_dev.h

@@ -345,9 +345,9 @@ struct mei_cl_device *mei_cl_add_device(struct mei_device *dev,
 					struct mei_cl_ops *ops);
 void mei_cl_remove_device(struct mei_cl_device *device);
 
-int __mei_cl_async_send(struct mei_cl *cl, u8 *buf, size_t length);
-int __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length);
-int __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length);
+ssize_t __mei_cl_async_send(struct mei_cl *cl, u8 *buf, size_t length);
+ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length);
+ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length);
 void mei_cl_bus_rx_event(struct mei_cl *cl);
 void mei_cl_bus_remove_devices(struct mei_device *dev);
 int mei_cl_bus_init(void);

include/linux/mei_cl_bus.h

@@ -25,8 +25,8 @@ int __mei_cl_driver_register(struct mei_cl_driver *driver,
 
 void mei_cl_driver_unregister(struct mei_cl_driver *driver);
 
-int mei_cl_send(struct mei_cl_device *device, u8 *buf, size_t length);
-int mei_cl_recv(struct mei_cl_device *device, u8 *buf, size_t length);
+ssize_t mei_cl_send(struct mei_cl_device *device, u8 *buf, size_t length);
+ssize_t  mei_cl_recv(struct mei_cl_device *device, u8 *buf, size_t length);
 
 typedef void (*mei_cl_event_cb_t)(struct mei_cl_device *device,
 			       u32 events, void *context);