This is a note to let you know that I've just added the patch titled tty: serial: fsl_lpuart: disable Rx/Tx DMA in lpuart32_shutdown() to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tty-serial-fsl_lpuart-disable-rx-tx-dma-in-lpuart32_.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 3d82c68361bf4b40c98ddc3d465ae35a73317640 Author: Sherry Sun <sherry.sun@xxxxxxx> Date: Fri Nov 25 18:19:52 2022 +0800 tty: serial: fsl_lpuart: disable Rx/Tx DMA in lpuart32_shutdown() [ Upstream commit 1d4bd0e4ae4ba95892bef919a8d4d3f08f122d7e ] UARTBAUD_RDMAE and UARTBAUD_TDMAE are enabled in lpuart32_startup(), but lpuart32_shutdown() not disable them, only free the dma ring buffer and release the dma channels, so here disable the Rx/Tx DMA first in lpuart32_shutdown(). Fixes: 42b68768e51b ("serial: fsl_lpuart: DMA support for 32-bit variant") Signed-off-by: Sherry Sun <sherry.sun@xxxxxxx> Link: https://lore.kernel.org/r/20221125101953.18753-3-sherry.sun@xxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index fc311df9f1c9d..24f9001d10242 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -1807,6 +1807,11 @@ static void lpuart32_shutdown(struct uart_port *port) spin_lock_irqsave(&port->lock, flags); + /* disable Rx/Tx DMA */ + temp = lpuart32_read(port, UARTBAUD); + temp &= ~(UARTBAUD_TDMAE | UARTBAUD_RDMAE); + lpuart32_write(port, temp, UARTBAUD); + /* disable Rx/Tx and interrupts */ temp = lpuart32_read(port, UARTCTRL); temp &= ~(UARTCTRL_TE | UARTCTRL_RE |