mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

tty: serial: fsl_lpuart: fix the wrong return value in lpuart32_get_mctrl 

Patch e60c2991f1 make the lpuart32_get_mctrl always return 0, actually
this will break the functions of device which use flow control such as
Bluetooth.
For lpuart32 plaform, the hardware can handle the CTS automatically.
So we should set TIOCM_CTS active. Also need to set CAR and DSR active.

Patch has been tested on lpuart32 platforms such as imx8qm and imx8ulp.

Fixes: e60c2991f1 ("serial: fsl_lpuart: remove RTSCTS handling from get_mctrl()")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20210729083109.31541-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Sherry Sun 2021-07-29 16:31:09 +08:00 committed by Greg Kroah-Hartman
parent 7f0909db76
commit 06e91df16f
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/tty/serial/fsl_lpuart.c
View File

@ -1415,7 +1415,7 @@ static unsigned int lpuart_get_mctrl(struct uart_port *port)
static unsigned int lpuart32_get_mctrl(struct uart_port *port)
{
unsigned int mctrl = 0;
unsigned int mctrl = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
u32 reg;
reg = lpuart32_read(port, UARTCTRL);