[char-misc-next] mei: bus: use ssize_t as the return type for send and receive

[char-misc-next] mei: bus: use ssize_t as the return type for send and receive

[Tomas Winkler]

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>
---
 drivers/misc/mei/bus.c     | 30 ++++++++++++++----------------
 drivers/misc/mei/mei_dev.h |  6 +++---
 include/linux/mei_cl_bus.h |  4 ++--
 3 files changed, 19 insertions(+), 21 deletions(-)

diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c
index b2de93724f5b..be767f4db26a 100644
--- a/drivers/misc/mei/bus.c
+++ b/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 = NULL;
 	struct mei_cl_cb *cb = NULL;
-	int rets;
+	ssize_t rets;
 
 	if (WARN_ON(!cl || !cl->dev))
 		return -ENODEV;
@@ -278,12 +278,12 @@ out:
 	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;
@@ -293,11 +293,9 @@ 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 &&
@@ -320,13 +318,13 @@ 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;
@@ -335,20 +333,20 @@ 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;
 
@@ -362,7 +360,7 @@ 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;
 
diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h
index 49c033158d43..363c093a7772 100644
--- a/drivers/misc/mei/mei_dev.h
+++ b/drivers/misc/mei/mei_dev.h
@@ -347,9 +347,9 @@ 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);
diff --git a/include/linux/mei_cl_bus.h b/include/linux/mei_cl_bus.h
index 164aad1f9f12..0819d36a3a74 100644
--- a/include/linux/mei_cl_bus.h
+++ b/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);
-- 
1.9.3

Re: [char-misc-next] mei: bus: use ssize_t as the return type for send and receive

[Greg KH]

On Mon, Nov 24, 2014 at 09:51:06AM +0200, Tomas Winkler wrote:
> 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>
> ---
>  drivers/misc/mei/bus.c     | 30 ++++++++++++++----------------
>  drivers/misc/mei/mei_dev.h |  6 +++---
>  include/linux/mei_cl_bus.h |  4 ++--
>  3 files changed, 19 insertions(+), 21 deletions(-)

Doesn't apply :(