diff options
| author | Heikki Krogerus <heikki.krogerus@linux.intel.com> | 2013-04-10 16:58:24 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-04-11 13:17:56 -0700 |
| commit | 5ea5b24da80322b8136cb000a7340cdc29a3d6dc (patch) | |
| tree | 3ec6da8909165463d6f4f81cdb1c505e87823f60 /drivers/tty/serial/8250 | |
| parent | 84f57d9e3685500a7447fc09a6891ce218869174 (diff) | |
serial: 8250_dma: TX cleanup
Removing one unneeded uart_write_wakeup(). There is no need
to start PIO transfer unless DMA fails, so this also changes
serial8250_tx_dma() to return 0 unless that is the case.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/8250')
| -rw-r--r-- | drivers/tty/serial/8250/8250_dma.c | 11 |
1 files changed, 4 insertions, 7 deletions
diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c index b9f7fd28112..ce2518d5dfd 100644 --- a/drivers/tty/serial/8250/8250_dma.c +++ b/drivers/tty/serial/8250/8250_dma.c @@ -33,10 +33,8 @@ static void __dma_tx_complete(void *param) if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) uart_write_wakeup(&p->port); - if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) { + if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) serial8250_tx_dma(p); - uart_write_wakeup(&p->port); - } } static void __dma_rx_complete(void *param) @@ -67,12 +65,11 @@ int serial8250_tx_dma(struct uart_8250_port *p) struct circ_buf *xmit = &p->port.state->xmit; struct dma_async_tx_descriptor *desc; - if (dma->tx_running) - return -EBUSY; + if (uart_tx_stopped(&p->port) || dma->tx_running || + uart_circ_empty(xmit)) + return 0; dma->tx_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); - if (!dma->tx_size) - return -EINVAL; desc = dmaengine_prep_slave_single(dma->txchan, dma->tx_addr + xmit->tail, |