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From:   Kartik <kkartik@nvidia.com>
To:     <ldewangan@nvidia.com>, <gregkh@linuxfoundation.org>,
        <jirislaby@kernel.org>, <thierry.reding@gmail.com>,
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        <akhilrajeev@nvidia.com>, <linux-serial@vger.kernel.org>,
        <linux-tegra@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: [PATCH] serial: tegra: read DMA status before terminating
Date:   Tue, 18 Oct 2022 11:55:11 +0530
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To get the valid data, read DMA status before terminating the DMA. As
dmaengine_terminate_all() deletes the DMA desc.

Fixes: e9ea096dd225 ("serial: tegra: add serial driver")

Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Signed-off-by: Kartik <kkartik@nvidia.com>
---
 drivers/tty/serial/serial-tegra.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c
index b7170cb9a544..2779b4491f02 100644
--- a/drivers/tty/serial/serial-tegra.c
+++ b/drivers/tty/serial/serial-tegra.c
@@ -619,8 +619,8 @@ static void tegra_uart_stop_tx(struct uart_port *u)
 	if (tup->tx_in_progress != TEGRA_UART_TX_DMA)
 		return;
 
-	dmaengine_terminate_all(tup->tx_dma_chan);
 	dmaengine_tx_status(tup->tx_dma_chan, tup->tx_cookie, &state);
+	dmaengine_terminate_all(tup->tx_dma_chan);
 	count = tup->tx_bytes_requested - state.residue;
 	async_tx_ack(tup->tx_dma_desc);
 	uart_xmit_advance(&tup->uport, count);
@@ -763,8 +763,8 @@ static void tegra_uart_terminate_rx_dma(struct tegra_uart_port *tup)
 		return;
 	}
 
-	dmaengine_terminate_all(tup->rx_dma_chan);
 	dmaengine_tx_status(tup->rx_dma_chan, tup->rx_cookie, &state);
+	dmaengine_terminate_all(tup->rx_dma_chan);
 
 	tegra_uart_rx_buffer_push(tup, state.residue);
 	tup->rx_dma_active = false;
-- 
2.17.1