From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4A7091868 for ; Wed, 28 Dec 2022 15:25:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A58E9C433D2; Wed, 28 Dec 2022 15:25:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672241117; bh=xzZyTAWzuVY9BUd3ys3fux0z9N2SLUeed5L8yZ51Iqg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YRsMKBodYG8JHvVzGnTzL/2mq0MOufzqDYHQBfCLlxqcqcJlTU1p95R6xZX22DDWo bu97wpZDv0l7eNJMcTUuuwl+MYk/5a65yuoXuloP2qJJIMKCF8kF/lbtvvGtheOrk2 Ss+XdFvb1pmQEfotsLD3Ky8G0z+bD63Y91GnYKPE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jon Hunter , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= , Thierry Reding , Akhil R , Kartik , Sasha Levin Subject: [PATCH 5.15 439/731] serial: tegra: Read DMA status before terminating Date: Wed, 28 Dec 2022 15:39:06 +0100 Message-Id: <20221228144309.284632016@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20221228144256.536395940@linuxfoundation.org> References: <20221228144256.536395940@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Kartik [ Upstream commit 109a951a9f1fd8a34ebd1896cbbd5d5cede880a7 ] 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 Signed-off-by: Sasha Levin --- drivers/tty/serial/serial-tegra.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c index d4dba298de7a..79187ff9ac13 100644 --- a/drivers/tty/serial/serial-tegra.c +++ b/drivers/tty/serial/serial-tegra.c @@ -619,8 +619,9 @@ 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); @@ -763,8 +764,9 @@ 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; -- 2.35.1