[Blackfin] serial driver: Fix bug serial driver in DMA mode spams history to console on shell restart

http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=2920
Fix by increasing buffer tail immediately before starting tx dma.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
This commit is contained in:
Sonic Zhang 2007-12-21 17:12:55 +08:00 committed by Bryan Wu
parent 75b780bd99
commit 99ee7b5f3a

View file

@ -411,6 +411,10 @@ static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
set_dma_x_count(uart->tx_dma_channel, uart->tx_count);
set_dma_x_modify(uart->tx_dma_channel, 1);
enable_dma(uart->tx_dma_channel);
xmit->tail = (xmit->tail + uart->tx_count) & (UART_XMIT_SIZE - 1);
uart->port.icount.tx += uart->tx_count;
#ifdef CONFIG_BF54x
UART_SET_IER(uart, ETBEI);
#else
@ -502,9 +506,6 @@ static irqreturn_t bfin_serial_dma_tx_int(int irq, void *dev_id)
ier &= ~ETBEI;
UART_PUT_IER(uart, ier);
#endif
xmit->tail = (xmit->tail+uart->tx_count) &(UART_XMIT_SIZE -1);
uart->port.icount.tx+=uart->tx_count;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&uart->port);