From: Tudor Ambarus Date: Thu, 25 Nov 2021 09:00:17 +0000 (+0200) Subject: tty: serial: atmel: Check return code of dmaengine_submit() X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=a170e9f8512ae61d6490d477daae2bfdcd66e0cb;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git tty: serial: atmel: Check return code of dmaengine_submit() [ Upstream commit 1e67bd2b8cb90b66e89562598e9c2046246832d3 ] The tx_submit() method of struct dma_async_tx_descriptor is entitled to do sanity checks and return errors if encountered. It's not the case for the DMA controller drivers that this client is using (at_h/xdmac), because they currently don't do sanity checks and always return a positive cookie at tx_submit() method. In case the controller drivers will implement sanity checks and return errors, print a message so that the client will be informed that something went wrong at tx_submit() level. Fixes: 08f738be88bb ("serial: at91: add tx dma support") Signed-off-by: Tudor Ambarus Acked-by: Richard Genoud Link: https://lore.kernel.org/r/20211125090028.786832-3-tudor.ambarus@microchip.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index a00227d312d3..9a56b88df95f 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -925,6 +925,11 @@ static void atmel_tx_dma(struct uart_port *port) desc->callback = atmel_complete_tx_dma; desc->callback_param = atmel_port; atmel_port->cookie_tx = dmaengine_submit(desc); + if (dma_submit_error(atmel_port->cookie_tx)) { + dev_err(port->dev, "dma_submit_error %d\n", + atmel_port->cookie_tx); + return; + } } if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) @@ -1183,6 +1188,11 @@ static int atmel_prepare_rx_dma(struct uart_port *port) desc->callback_param = port; atmel_port->desc_rx = desc; atmel_port->cookie_rx = dmaengine_submit(desc); + if (dma_submit_error(atmel_port->cookie_rx)) { + dev_err(port->dev, "dma_submit_error %d\n", + atmel_port->cookie_rx); + goto chan_err; + } return 0;