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From: Krishna Yarlagadda <kyarlagadda@nvidia.com>
To: <gregkh@linuxfoundation.org>, <robh+dt@kernel.org>,
	<mark.rutland@arm.com>, <thierry.reding@gmail.com>,
	<jonathanh@nvidia.com>, <ldewangan@nvidia.com>, <jslaby@suse.com>
Cc: <linux-serial@vger.kernel.org>, <devicetree@vger.kernel.org>,
	<linux-tegra@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	"Shardar Shariff Md" <smohammed@nvidia.com>,
	Krishna Yarlagadda <kyarlagadda@nvidia.com>
Subject: [PATCH 02/14] serial: tegra: add support to ignore read
Date: Mon, 12 Aug 2019 16:58:11 +0530	[thread overview]
Message-ID: <1565609303-27000-3-git-send-email-kyarlagadda@nvidia.com> (raw)
In-Reply-To: <1565609303-27000-1-git-send-email-kyarlagadda@nvidia.com>

From: Shardar Shariff Md <smohammed@nvidia.com>

Add support to ignore read characters if CREAD flag is not set.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
---
 drivers/tty/serial/serial-tegra.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c
index 19f4c24..93d299e 100644
--- a/drivers/tty/serial/serial-tegra.c
+++ b/drivers/tty/serial/serial-tegra.c
@@ -542,6 +542,9 @@ static void tegra_uart_handle_rx_pio(struct tegra_uart_port *tup,
 		ch = (unsigned char) tegra_uart_read(tup, UART_RX);
 		tup->uport.icount.rx++;
 
+		if (tup->uport.ignore_status_mask & UART_LSR_DR)
+			continue;
+
 		if (!uart_handle_sysrq_char(&tup->uport, ch) && tty)
 			tty_insert_flip_char(tty, ch, flag);
 	} while (1);
@@ -562,6 +565,10 @@ static void tegra_uart_copy_rx_to_tty(struct tegra_uart_port *tup,
 		dev_err(tup->uport.dev, "No tty port\n");
 		return;
 	}
+
+	if (tup->uport.ignore_status_mask & UART_LSR_DR)
+		return;
+
 	dma_sync_single_for_cpu(tup->uport.dev, tup->rx_dma_buf_phys,
 				TEGRA_UART_RX_DMA_BUFFER_SIZE, DMA_FROM_DEVICE);
 	copied = tty_insert_flip_string(tty,
@@ -1190,6 +1197,11 @@ static void tegra_uart_set_termios(struct uart_port *u,
 	tegra_uart_write(tup, tup->ier_shadow, UART_IER);
 	tegra_uart_read(tup, UART_IER);
 
+	tup->uport.ignore_status_mask = 0;
+	/* Ignore all characters if CREAD is not set */
+	if ((termios->c_cflag & CREAD) == 0)
+		tup->uport.ignore_status_mask |= UART_LSR_DR;
+
 	spin_unlock_irqrestore(&u->lock, flags);
 }
 
-- 
2.7.4


  parent reply	other threads:[~2019-08-12 11:28 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-12 11:28 [PATCH 00/14] serial: tegra: Tegra186 support and fixes Krishna Yarlagadda
2019-08-12 11:28 ` [PATCH 01/14] serial: tegra: add internal loopback functionality Krishna Yarlagadda
2019-08-13  9:38   ` Thierry Reding
2019-08-12 11:28 ` Krishna Yarlagadda [this message]
2019-08-13  9:42   ` [PATCH 02/14] serial: tegra: add support to ignore read Thierry Reding
2019-08-27  9:29     ` Krishna Yarlagadda
2019-08-12 11:28 ` [PATCH 03/14] serial: tegra: avoid reg access when clk disabled Krishna Yarlagadda
2019-08-13  9:45   ` Thierry Reding
2019-08-27  9:29     ` Krishna Yarlagadda
2019-08-12 11:28 ` [PATCH 04/14] serial: tegra: protect IER against LCR.DLAB Krishna Yarlagadda
2019-08-13  9:46   ` Thierry Reding
2019-08-12 11:28 ` [PATCH 05/14] serial: tegra: flush the RX fifo on frame error Krishna Yarlagadda
2019-08-13  9:48   ` Thierry Reding
2019-08-27  9:29     ` Krishna Yarlagadda
2019-08-12 11:28 ` [PATCH 06/14] serial: tegra: report error to upper tty layer Krishna Yarlagadda
2019-08-13  9:52   ` Thierry Reding
2019-08-27  9:29     ` Krishna Yarlagadda
2019-08-12 11:28 ` [PATCH 07/14] serial: tegra: add compatible for new chips Krishna Yarlagadda
2019-08-13  9:55   ` Thierry Reding
2019-08-27  9:29     ` Krishna Yarlagadda
2019-08-12 11:28 ` [PATCH 08/14] serial: tegra: check for FIFO mode enabled status Krishna Yarlagadda
2019-08-13 10:03   ` Thierry Reding
2019-08-27  9:29     ` Krishna Yarlagadda
2019-08-12 11:28 ` [PATCH 09/14] serial: tegra: set maximum num of uart ports to 8 Krishna Yarlagadda
2019-08-13 10:19   ` Thierry Reding
2019-08-27  9:30     ` Krishna Yarlagadda
2019-08-12 11:28 ` [PATCH 10/14] serial: tegra: add support to use 8 bytes trigger Krishna Yarlagadda
2019-08-19 20:29   ` Jon Hunter
2019-08-27  9:31     ` Krishna Yarlagadda
2019-08-12 11:28 ` [PATCH 11/14] serial: tegra: DT for Adjusted baud rates Krishna Yarlagadda
2019-08-13 10:24   ` Thierry Reding
2019-08-27  9:31     ` Krishna Yarlagadda
2019-08-12 11:28 ` [PATCH 12/14] serial: tegra: add support to adjust baud rate Krishna Yarlagadda
2019-08-12 11:28 ` [PATCH 13/14] serial: tegra: report clk rate errors Krishna Yarlagadda
2019-08-12 11:28 ` [PATCH 14/14] serial: tegra: Add PIO mode support Krishna Yarlagadda

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