serial: 8250_dma: check the result of TX buffer mapping

Using dma_mapping_error() to make sure the mapping did not
fail.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Heikki Krogerus 2014-04-28 15:59:56 +03:00 committed by Greg Kroah-Hartman
parent 06aa82e498
commit d4089a3328

View File

@ -192,21 +192,28 @@ int serial8250_request_dma(struct uart_8250_port *p)
dma->rx_buf = dma_alloc_coherent(dma->rxchan->device->dev, dma->rx_size,
&dma->rx_addr, GFP_KERNEL);
if (!dma->rx_buf) {
dma_release_channel(dma->rxchan);
dma_release_channel(dma->txchan);
return -ENOMEM;
}
if (!dma->rx_buf)
goto err;
/* TX buffer */
dma->tx_addr = dma_map_single(dma->txchan->device->dev,
p->port.state->xmit.buf,
UART_XMIT_SIZE,
DMA_TO_DEVICE);
if (dma_mapping_error(dma->txchan->device->dev, dma->tx_addr)) {
dma_free_coherent(dma->rxchan->device->dev, dma->rx_size,
dma->rx_buf, dma->rx_addr);
goto err;
}
dev_dbg_ratelimited(p->port.dev, "got both dma channels\n");
return 0;
err:
dma_release_channel(dma->rxchan);
dma_release_channel(dma->txchan);
return -ENOMEM;
}
EXPORT_SYMBOL_GPL(serial8250_request_dma);