diff options
Diffstat (limited to 'drivers/spi/spi.c')
| -rw-r--r-- | drivers/spi/spi.c | 19 |
1 files changed, 8 insertions, 11 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index b31f4431849..93e9de46977 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -541,10 +541,7 @@ static void spi_complete(void *arg) * 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 @@ int spi_sync(struct spi_device *spi, struct spi_message *message) 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; } @@ -589,7 +588,7 @@ int spi_write_then_read(struct spi_device *spi, const u8 *txbuf, unsigned n_tx, u8 *rxbuf, unsigned n_rx) { - static DECLARE_MUTEX(lock); + static DEFINE_MUTEX(lock); int status; struct spi_message message; @@ -615,7 +614,7 @@ int spi_write_then_read(struct spi_device *spi, } /* ... unless someone else is using the pre-allocated buffer */ - if (down_trylock(&lock)) { + if (!mutex_trylock(&lock)) { local_buf = kmalloc(SPI_BUFSIZ, GFP_KERNEL); if (!local_buf) return -ENOMEM; @@ -628,13 +627,11 @@ int spi_write_then_read(struct spi_device *spi, /* 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) - up(&lock); + mutex_unlock(&lock); else kfree(local_buf); |