Example #1
0
static void serial_omap_start_tx(struct uart_port *port)
{
	struct uart_omap_port *up = (struct uart_omap_port *)port;
	struct circ_buf *xmit;
	unsigned int start;
	int ret = 0;

	if (!up->use_dma) {
		serial_omap_enable_ier_thri(up);
		return;
	}

	if (up->uart_dma.tx_dma_used)
		return;

	xmit = &up->port.state->xmit;

	if (up->uart_dma.tx_dma_channel == OMAP_UART_DMA_CH_FREE) {
		ret = omap_request_dma(up->uart_dma.uart_dma_tx,
				"UART Tx DMA",
				(void *)uart_tx_dma_callback, up,
				&(up->uart_dma.tx_dma_channel));

		if (ret < 0) {
			serial_omap_enable_ier_thri(up);
			return;
		}
	}
	spin_lock(&(up->uart_dma.tx_lock));
	up->uart_dma.tx_dma_used = true;
	spin_unlock(&(up->uart_dma.tx_lock));

	start = up->uart_dma.tx_buf_dma_phys +
				(xmit->tail & (UART_XMIT_SIZE - 1));

	up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
	/*
	 * It is a circular buffer. See if the buffer has wounded back.
	 * If yes it will have to be transferred in two separate dma
	 * transfers
	 */
	if (start + up->uart_dma.tx_buf_size >=
			up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
		up->uart_dma.tx_buf_size =
			(up->uart_dma.tx_buf_dma_phys +
			UART_XMIT_SIZE) - start;

	omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
				OMAP_DMA_AMODE_CONSTANT,
				up->uart_dma.uart_base, 0, 0);
	omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
				OMAP_DMA_AMODE_POST_INC, start, 0, 0);
	omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
				OMAP_DMA_DATA_TYPE_S8,
				up->uart_dma.tx_buf_size, 1,
				OMAP_DMA_SYNC_ELEMENT,
				up->uart_dma.uart_dma_tx, 0);
	/* FIXME: Cache maintenance needed here? */
	omap_start_dma(up->uart_dma.tx_dma_channel);
}
Example #2
0
static void serial_omap_start_tx(struct uart_port *port)
{
	struct uart_omap_port *up = to_uart_omap_port(port);
	int res;

	pm_runtime_get_sync(up->dev);

	/* Handle RS-485 */
	if (port->rs485.flags & SER_RS485_ENABLED) {
		/* Fire THR interrupts when FIFO is below trigger level */
		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
		serial_out(up, UART_OMAP_SCR, up->scr);

		/* if rts not already enabled */
		res = (port->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
		if (gpio_get_value(up->rts_gpio) != res) {
			gpio_set_value(up->rts_gpio, res);
			if (port->rs485.delay_rts_before_send > 0)
				mdelay(port->rs485.delay_rts_before_send);
		}
	}

	if ((port->rs485.flags & SER_RS485_ENABLED) &&
	    !(port->rs485.flags & SER_RS485_RX_DURING_TX))
		serial_omap_stop_rx(port);

	serial_omap_enable_ier_thri(up);
	pm_runtime_mark_last_busy(up->dev);
	pm_runtime_put_autosuspend(up->dev);
}
Example #3
0
static void serial_omap_stop_tx(struct uart_port *port)
{
	struct uart_omap_port *up = (struct uart_omap_port *)port;

	if (up->use_dma &&
		up->uart_dma.tx_dma_channel != OMAP_UART_DMA_CH_FREE) {
		/*
		 * Check if dma is still active. If yes do nothing,
		 * return. Else stop dma
		 */
		if (omap_get_dma_active_status(up->uart_dma.tx_dma_channel))
			return;
		omap_stop_dma(up->uart_dma.tx_dma_channel);
		omap_free_dma(up->uart_dma.tx_dma_channel);
		up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
	}

	if (!(up->rs485.flags & SER_RS485_ENABLED)) {
		serial_omap_disable_ier_thri(up);
		return;
	}

	up->tx_wait_end = 1;
	serial_omap_thri_mode(up);
	serial_omap_enable_ier_thri(up);
}
static void serial_omap_start_tx(struct uart_port *port)
{
	struct uart_omap_port *up = to_uart_omap_port(port);

	pm_runtime_get_sync(up->dev);
	serial_omap_enable_ier_thri(up);
	pm_runtime_mark_last_busy(up->dev);
	pm_runtime_put_autosuspend(up->dev);
}
static void serial_omap_start_tx(struct uart_port *port)
{
	struct uart_omap_port *up = (struct uart_omap_port *)port;
	struct omap_uart_port_info *pdata = up->pdev->dev.platform_data;
	struct circ_buf *xmit;
	unsigned int start;
	int ret = 0;

	if (!up->use_dma) {
		pm_runtime_get_sync(&up->pdev->dev);
		serial_omap_enable_ier_thri(up);
		if (pdata && pdata->set_noidle)
			pdata->set_noidle(up->pdev);
		pm_runtime_mark_last_busy(&up->pdev->dev);
		pm_runtime_put_autosuspend(&up->pdev->dev);
		return;
	}

	if (up->uart_dma.tx_dma_used)
		return;

	xmit = &up->port.state->xmit;

	if (up->uart_dma.tx_dma_channel == OMAP_UART_DMA_CH_FREE) {
		pm_runtime_get_sync(&up->pdev->dev);
		ret = omap_request_dma(up->uart_dma.uart_dma_tx,
				"UART Tx DMA",
				(void *)uart_tx_dma_callback, up,
				&(up->uart_dma.tx_dma_channel));

		if (ret < 0) {
			serial_omap_enable_ier_thri(up);
			return;
		}
	}
	spin_lock(&(up->uart_dma.tx_lock));
	up->uart_dma.tx_dma_used = true;
	spin_unlock(&(up->uart_dma.tx_lock));

	start = up->uart_dma.tx_buf_dma_phys +
				(xmit->tail & (UART_XMIT_SIZE - 1));

	up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
	if (start + up->uart_dma.tx_buf_size >=
			up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
		up->uart_dma.tx_buf_size =
			(up->uart_dma.tx_buf_dma_phys +
			UART_XMIT_SIZE) - start;

	omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
				OMAP_DMA_AMODE_CONSTANT,
				up->uart_dma.uart_base, 0, 0);
	omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
				OMAP_DMA_AMODE_POST_INC, start, 0, 0);
	omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
				OMAP_DMA_DATA_TYPE_S8,
				up->uart_dma.tx_buf_size, 1,
				OMAP_DMA_SYNC_ELEMENT,
				up->uart_dma.uart_dma_tx, 0);
	
	omap_start_dma(up->uart_dma.tx_dma_channel);
}