korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2025-01-04 04:44:37 +08:00
Code Issues Packages Projects Releases Wiki Activity

tty: serial: fsl_lpuart: Clear the error flags by writing 1 for lpuart32 platforms

Browse Source 
Do not read the data register to clear the error flags for lpuart32
platforms, the additional read may cause the receive FIFO underflow
since the DMA has already read the data register.
Actually all lpuart32 platforms support write 1 to clear those error
bits, let's use this method to better clear the error flags.

Fixes: 42b68768e5 ("serial: fsl_lpuart: DMA support for 32-bit variant")
Cc: stable <stable@kernel.org>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20230801022304.24251-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Sherry Sun 2023-08-01 10:23:04 +08:00 committed by Greg Kroah-Hartman
parent 5d0c230f1d
commit 282069845a
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/tty/serial/fsl_lpuart.c
View File

@ -1139,8 +1139,8 @@ static void lpuart_copy_rx_to_tty(struct lpuart_port *sport)
unsigned long sr = lpuart32_read(&sport->port, UARTSTAT);
if (sr & (UARTSTAT_PE | UARTSTAT_FE)) {
/* Read DR to clear the error flags */
lpuart32_read(&sport->port, UARTDATA);
/* Clear the error flags */
lpuart32_write(&sport->port, sr, UARTSTAT);
if (sr & UARTSTAT_PE)
sport->port.icount.parity++;