Пример #1
0
static void __dma_tx_complete(void *param)
{
	struct uart_8250_port	*p = param;
	struct uart_8250_dma	*dma = p->dma;
	struct circ_buf		*xmit = &p->port.state->xmit;
	unsigned long	flags;
	int		ret;

	dma_sync_single_for_cpu(dma->txchan->device->dev, dma->tx_addr,
				UART_XMIT_SIZE, DMA_TO_DEVICE);

	spin_lock_irqsave(&p->port.lock, flags);

	dma->tx_running = 0;

	xmit->tail += dma->tx_size;
	xmit->tail &= UART_XMIT_SIZE - 1;
	p->port.icount.tx += dma->tx_size;

	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
		uart_write_wakeup(&p->port);

	ret = serial8250_tx_dma(p);
	if (ret) {
		p->ier |= UART_IER_THRI;
		serial_port_out(&p->port, UART_IER, p->ier);
	}

	spin_unlock_irqrestore(&p->port.lock, flags);
}
Пример #2
0
static void omap_8250_dma_tx_complete(void *param)
{
	struct uart_8250_port	*p = param;
	struct uart_8250_dma	*dma = p->dma;
	struct circ_buf		*xmit = &p->port.state->xmit;
	unsigned long		flags;
	bool			en_thri = false;
	struct omap8250_priv	*priv = p->port.private_data;

	dma_sync_single_for_cpu(dma->txchan->device->dev, dma->tx_addr,
				UART_XMIT_SIZE, DMA_TO_DEVICE);

	spin_lock_irqsave(&p->port.lock, flags);

	dma->tx_running = 0;

	xmit->tail += dma->tx_size;
	xmit->tail &= UART_XMIT_SIZE - 1;
	p->port.icount.tx += dma->tx_size;

	if (priv->delayed_restore) {
		priv->delayed_restore = 0;
		omap8250_restore_regs(p);
	}

	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
		uart_write_wakeup(&p->port);

	if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) {
		int ret;

		ret = omap_8250_tx_dma(p);
		if (ret)
			en_thri = true;

	} else if (p->capabilities & UART_CAP_RPM) {
		en_thri = true;
	}

	if (en_thri) {
		dma->tx_err = 1;
		p->ier |= UART_IER_THRI;
		serial_port_out(&p->port, UART_IER, p->ier);
	}

	spin_unlock_irqrestore(&p->port.lock, flags);
}
Пример #3
0
static void
mtk8250_set_termios(struct uart_port *port, struct ktermios *termios,
			struct ktermios *old)
{
	struct uart_8250_port *up = up_to_u8250p(port);
	unsigned long flags;
	unsigned int baud, quot;

#ifdef CONFIG_SERIAL_8250_DMA
	if (up->dma) {
		if (uart_console(port)) {
			devm_kfree(up->port.dev, up->dma);
			up->dma = NULL;
		} else {
			mtk8250_dma_enable(up);
		}
	}
#endif

	serial8250_do_set_termios(port, termios, old);

	/*
	 * Mediatek UARTs use an extra highspeed register (UART_MTK_HIGHS)
	 *
	 * We need to recalcualte the quot register, as the claculation depends
	 * on the vaule in the highspeed register.
	 *
	 * Some baudrates are not supported by the chip, so we use the next
	 * lower rate supported and update termios c_flag.
	 *
	 * If highspeed register is set to 3, we need to specify sample count
	 * and sample point to increase accuracy. If not, we reset the
	 * registers to their default values.
	 */
	baud = uart_get_baud_rate(port, termios, old,
				  port->uartclk / 16 / UART_DIV_MAX,
				  port->uartclk);

	if (baud <= 115200) {
		serial_port_out(port, UART_MTK_HIGHS, 0x0);
		quot = uart_get_divisor(port, baud);
	} else if (baud <= 576000) {
		serial_port_out(port, UART_MTK_HIGHS, 0x2);

		/* Set to next lower baudrate supported */
		if ((baud == 500000) || (baud == 576000))
			baud = 460800;
		quot = DIV_ROUND_UP(port->uartclk, 4 * baud);
	} else {
		serial_port_out(port, UART_MTK_HIGHS, 0x3);
		quot = DIV_ROUND_UP(port->uartclk, 256 * baud);
	}

	/*
	 * Ok, we're now changing the port state.  Do it with
	 * interrupts disabled.
	 */
	spin_lock_irqsave(&port->lock, flags);

	/* set DLAB we have cval saved in up->lcr from the call to the core */
	serial_port_out(port, UART_LCR, up->lcr | UART_LCR_DLAB);
	serial_dl_write(up, quot);

	/* reset DLAB */
	serial_port_out(port, UART_LCR, up->lcr);

	if (baud > 460800) {
		unsigned int tmp;

		tmp = DIV_ROUND_CLOSEST(port->uartclk, quot * baud);
		serial_port_out(port, UART_MTK_SAMPLE_COUNT, tmp - 1);
		serial_port_out(port, UART_MTK_SAMPLE_POINT,
					(tmp - 2) >> 1);
	} else {