diff options
Diffstat (limited to 'drivers/tty/serial/imx.c')
| -rw-r--r-- | drivers/tty/serial/imx.c | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 630065b551f5..dfa2db6ed322 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -538,6 +538,11 @@ static void dma_tx_callback(void *data) if (!uart_circ_empty(xmit) && !uart_tx_stopped(&sport->port)) imx_dma_tx(sport); + else if (sport->port.rs485.flags & SER_RS485_ENABLED) { + temp = readl(sport->port.membase + UCR4); + temp |= UCR4_TCEN; + writel(temp, sport->port.membase + UCR4); + } spin_unlock_irqrestore(&sport->port.lock, flags); } @@ -555,6 +560,10 @@ static void imx_dma_tx(struct imx_port *sport) if (sport->dma_is_txing) return; + temp = readl(sport->port.membase + UCR4); + temp &= ~UCR4_TCEN; + writel(temp, sport->port.membase + UCR4); + sport->tx_bytes = uart_circ_chars_pending(xmit); if (xmit->tail < xmit->head || xmit->head == 0) { @@ -617,10 +626,15 @@ static void imx_start_tx(struct uart_port *port) if (!(port->rs485.flags & SER_RS485_RX_DURING_TX)) imx_stop_rx(port); - /* enable transmitter and shifter empty irq */ - temp = readl(port->membase + UCR4); - temp |= UCR4_TCEN; - writel(temp, port->membase + UCR4); + /* + * Enable transmitter and shifter empty irq only if DMA is off. + * In the DMA case this is done in the tx-callback. + */ + if (!sport->dma_is_enabled) { + temp = readl(port->membase + UCR4); + temp |= UCR4_TCEN; + writel(temp, port->membase + UCR4); + } } if (!sport->dma_is_enabled) { |