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From: Jiada Wang <jiada_wang@mentor.com>
To: <gregkh@linuxfoundation.org>, <jslaby@suse.cz>,
	<linux-serial@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Cc: <jiada_wang@mentor.com>, <anton_bondarenko@mentor.com>,
	<dirk.behme@de.bosch.com>
Subject: [PATCH v1 11/15] serial: imx: initialized DMA w/o HW flow enabled
Date: Tue, 9 Dec 2014 18:11:32 +0900	[thread overview]
Message-ID: <1418116296-12082-12-git-send-email-jiada_wang@mentor.com> (raw)
In-Reply-To: <1418116296-12082-1-git-send-email-jiada_wang@mentor.com>

From: Anton Bondarenko <anton_bondarenko@mentor.com>

DMA mode for UART can be used even w/o HW flow control with RTS/CTS.
So it need to be initialized and enabled earlier.

Signed-off-by: Anton Bondarenko <anton_bondarenko@mentor.com>
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
 drivers/tty/serial/imx.c | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index d501628..a0f27b4 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -1173,12 +1173,20 @@ static int imx_startup(struct uart_port *port)
 		}
 	}
 
+	/* Can we enable the DMA support? */
+	if (is_imx6q_uart(sport) && !uart_console(port) &&
+	    !sport->dma_is_inited)
+		imx_uart_dma_init(sport);
+
 	spin_lock_irqsave(&sport->port.lock, flags);
 	/*
 	 * Finally, clear and enable interrupts
 	 */
 	writel(USR1_RTSD, sport->port.membase + USR1);
 
+	if (sport->dma_is_inited && !sport->dma_is_enabled)
+		imx_enable_dma(sport);
+
 	temp = readl(sport->port.membase + UCR1);
 	temp |= UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN;
 
@@ -1378,11 +1386,6 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios,
 		if (sport->have_rtscts) {
 			ucr2 &= ~UCR2_IRTS;
 			ucr2 |= UCR2_CTSC;
-
-			/* Can we enable the DMA support? */
-			if (is_imx6q_uart(sport) && !uart_console(port)
-				&& !sport->dma_is_inited)
-				imx_uart_dma_init(sport);
 		} else {
 			termios->c_cflag &= ~CRTSCTS;
 		}
@@ -1504,8 +1507,6 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios,
 	if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
 		imx_enable_ms(&sport->port);
 
-	if (sport->dma_is_inited && !sport->dma_is_enabled)
-		imx_enable_dma(sport);
 	spin_unlock_irqrestore(&sport->port.lock, flags);
 }
 
-- 
1.9.3


  parent reply	other threads:[~2014-12-09  9:12 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-12-09  9:11 [PATCH v1 00/15] serial: imx: misc fix and features Jiada Wang
2014-12-09  9:11 ` [PATCH v1 01/15] serial: imx: add CREAD flag support Jiada Wang
2014-12-09  9:11 ` [PATCH v1 02/15] serial: imx: use locking to stop concurrent access of UCR1 Jiada Wang
2014-12-09  9:11 ` [PATCH v1 03/15] serial: imx: remove unneeded imx_transmit_buffer() from imx_start_tx() Jiada Wang
2014-12-09  9:11 ` [PATCH v1 04/15] serial: imx: TX DMA: clean up sg initialization Jiada Wang
2014-12-09  9:11 ` [PATCH v1 05/15] serial: imx: unmap sg in case of dmaengine_prep_slave_sg() failure Jiada Wang
2014-12-09  9:11 ` [PATCH v1 06/15] serial: imx: unmap scatter gather list in imx_flush_buffer Jiada Wang
2014-12-09  9:11 ` [PATCH v1 07/15] serial: imx: use dma_is_txing to synchronize dma_tx_callback and imx_dma_tx Jiada Wang
2014-12-09  9:11 ` [PATCH v1 08/15] Revert "serial: imx: always wake up the processes in the TX callback" Jiada Wang
2014-12-09  9:11 ` [PATCH v1 09/15] serial: imx: call imx_dma_tx() again in dma_tx_callback Jiada Wang
2014-12-09  9:11 ` [PATCH v1 10/15] serial: imx: disable TDMAEN in imx_flush_buffer() Jiada Wang
2014-12-09  9:11 ` Jiada Wang [this message]
2015-04-09 12:00   ` [PATCH v1 11/15] serial: imx: initialized DMA w/o HW flow enabled Sebastian Andrzej Siewior
2015-04-13  7:40     ` jiwang
2015-04-13  8:06       ` Sebastian Andrzej Siewior
2015-04-17  9:18         ` jiwang
2015-04-17 10:31           ` Sebastian Andrzej Siewior
2015-05-06 16:08           ` Nicolae Rosia
2015-05-06 16:12             ` Sebastian Andrzej Siewior
2015-05-06 16:46               ` Nicolae Rosia
2015-05-06 17:30                 ` Sebastian Andrzej Siewior
2015-05-07 13:55                   ` Nicolae Rosia
2015-05-07 13:58                     ` Sebastian Andrzej Siewior
2014-12-09  9:11 ` [PATCH v1 12/15] serial: imx: start rx_dma once RXFIFO is not empty Jiada Wang
2014-12-09  9:11 ` [PATCH v1 13/15] serial: imx: Enable UCR4_OREN in startup interface Jiada Wang
2014-12-09  9:11 ` [PATCH v1 14/15] serial: imx: Fix issue in software flow control Jiada Wang
2014-12-09  9:11 ` [PATCH v1 15/15] serial: imx: Support sw flow control in DMA mode Jiada Wang

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