spi: simplify spi_sync() calling convention
Simplify spi_sync calling convention, eliminating the need to check both
the return value AND the message->status. In consequence, this corrects
misbehaviours of spi_read and spi_write (which only checked the former) and
their callers.
Signed-off-by: Marc Pignat <marc.pignat@hevs.ch>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 6ca07c9..93e9de4 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -541,10 +541,7 @@
* Also, the caller is guaranteeing that the memory associated with the
* message will not be freed before this call returns.
*
- * The return value is a negative error code if the message could not be
- * submitted, else zero. When the value is zero, then message->status is
- * also defined; it's the completion code for the transfer, either zero
- * or a negative error code from the controller driver.
+ * It returns zero on success, else a negative error code.
*/
int spi_sync(struct spi_device *spi, struct spi_message *message)
{
@@ -554,8 +551,10 @@
message->complete = spi_complete;
message->context = &done;
status = spi_async(spi, message);
- if (status == 0)
+ if (status == 0) {
wait_for_completion(&done);
+ status = message->status;
+ }
message->context = NULL;
return status;
}
@@ -628,10 +627,8 @@
/* do the i/o */
status = spi_sync(spi, &message);
- if (status == 0) {
+ if (status == 0)
memcpy(rxbuf, x[1].rx_buf, n_rx);
- status = message.status;
- }
if (x[0].tx_buf == buf)
mutex_unlock(&lock);