[PATCH 3/4] serial: tegra: Remove redundant code and check in tegra_uart_stop_rx()

From: Jon Hunter
Date: Fri Oct 09 2015 - 09:50:25 EST


The serial-tegra driver always uses DMA and hence the driver always
allocates DMA channels. Therefore, the test to see if the RX DMA channel
is initialised in tegra_uart_stop_rx() is unnecessary and so remove
the test and the code that corresponds to the case where the RX DMA
channel is not initialised. Please note that the call to
tegra_uart_stop_rx() should always be before the call to
tegra_uart_shutdown() which will uninitialise the RX DMA channel.

Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx>
---
drivers/tty/serial/serial-tegra.c | 17 +++++++----------
1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c
index 42583484d4b2..11aa5e1e3705 100644
--- a/drivers/tty/serial/serial-tegra.c
+++ b/drivers/tty/serial/serial-tegra.c
@@ -777,16 +777,13 @@ static void tegra_uart_stop_rx(struct uart_port *u)
tup->ier_shadow = ier;
tegra_uart_write(tup, ier, UART_IER);
tup->rx_in_progress = 0;
- if (tup->rx_dma_chan) {
- dmaengine_terminate_all(tup->rx_dma_chan);
- dmaengine_tx_status(tup->rx_dma_chan, tup->rx_cookie, &state);
- async_tx_ack(tup->rx_dma_desc);
- count = tup->rx_bytes_requested - state.residue;
- tegra_uart_copy_rx_to_tty(tup, port, count);
- tegra_uart_handle_rx_pio(tup, port);
- } else {
- tegra_uart_handle_rx_pio(tup, port);
- }
+ dmaengine_terminate_all(tup->rx_dma_chan);
+ dmaengine_tx_status(tup->rx_dma_chan, tup->rx_cookie, &state);
+ async_tx_ack(tup->rx_dma_desc);
+ count = tup->rx_bytes_requested - state.residue;
+ tegra_uart_copy_rx_to_tty(tup, port, count);
+ tegra_uart_handle_rx_pio(tup, port);
+
if (tty) {
tty_flip_buffer_push(port);
tty_kref_put(tty);
--
2.1.4

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