iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

serial: uartps: Add a timeout to the tx empty wait

Browse Source 
[ Upstream commit 277375b864e8147975b064b513f491e2a910e66a ]

In case the cable is not connected then the target gets into
an infinite wait for tx empty.
Add a timeout to the tx empty wait.

Reported-by: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Shubhrajyoti Datta 2020-02-10 10:18:25 -07:00 committed by Greg Kroah-Hartman
parent 0cffbe2a1b
commit 6933267346
1 changed files with 10 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
drivers/tty/serial/xilinx_uartps.c
View File

@ -31,6 +31,7 @@
#include <linux/of.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
#include <linux/iopoll.h>
#define CDNS_UART_TTY_NAME "ttyPS"
#define CDNS_UART_NAME "xuartps"
@ -39,6 +40,7 @@
#define CDNS_UART_NR_PORTS 2
#define CDNS_UART_FIFO_SIZE 64 /* FIFO size */
#define CDNS_UART_REGISTER_SPACE 0x1000
#define TX_TIMEOUT 500000
/* Rx Trigger level */
static int rx_trigger_level = 56;
@ -685,16 +687,20 @@ static void cdns_uart_set_termios(struct uart_port *port,
unsigned int cval = 0;
unsigned int baud, minbaud, maxbaud;
unsigned long flags;
unsigned int ctrl_reg, mode_reg;
unsigned int ctrl_reg, mode_reg, val;
int err;
spin_lock_irqsave(&port->lock, flags);
/* Wait for the transmit FIFO to empty before making changes */
if (!(readl(port->membase + CDNS_UART_CR) &
CDNS_UART_CR_TX_DIS)) {
while (!(readl(port->membase + CDNS_UART_SR) &
CDNS_UART_SR_TXEMPTY)) {
cpu_relax();
err = readl_poll_timeout(port->membase + CDNS_UART_SR,
val, (val & CDNS_UART_SR_TXEMPTY),
1000, TX_TIMEOUT);
if (err) {
dev_err(port->dev, "timed out waiting for tx empty");
return;
}
}