From: Kartik Date: Tue, 18 Oct 2022 14:58:06 +0000 (+0530) Subject: serial: tegra: Read DMA status before terminating X-Git-Tag: v6.6.7~3882^2~43 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=109a951a9f1fd8a34ebd1896cbbd5d5cede880a7;p=platform%2Fkernel%2Flinux-starfive.git serial: tegra: Read DMA status before terminating Read the DMA status before terminating the DMA, as doing so deletes the DMA desc. Also, to get the correct transfer status information, pause the DMA using dmaengine_pause() before reading the DMA status. Fixes: e9ea096dd225 ("serial: tegra: add serial driver") Reviewed-by: Jon Hunter Reviewed-by: Ilpo Järvinen Acked-by: Thierry Reding Signed-off-by: Akhil R Signed-off-by: Kartik Link: https://lore.kernel.org/r/1666105086-17326-1-git-send-email-kkartik@nvidia.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c index 4304e3f..e5b9773 100644 --- a/drivers/tty/serial/serial-tegra.c +++ b/drivers/tty/serial/serial-tegra.c @@ -618,8 +618,9 @@ 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_pause(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); @@ -762,8 +763,9 @@ static void tegra_uart_terminate_rx_dma(struct tegra_uart_port *tup) return; } - dmaengine_terminate_all(tup->rx_dma_chan); + dmaengine_pause(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;