[lkml]   [2017]   [Mar]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH] tty/serial: atmel: fix TX path in atmel_console_write()
A side effect of 89d8232411a8 ("tty/serial: atmel_serial: BUG: stop DMA
from transmitting in stop_tx") is that the console can be called with
TX path disabled. Then the system would hang trying to push charecters
out in atmel_console_putchar().

Signed-off-by: Nicolas Ferre <>
Fixes: 89d8232411a8 ("tty/serial: atmel_serial: BUG: stop DMA from transmitting
in stop_tx")
Cc: stable <> #4.4+
Acked-by: Richard Genoud <>

I resend this patch removing the "RFC" tag and adding the Acked-by: Richard.

Best regards,

drivers/tty/serial/atmel_serial.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index d9c05e05d896..2a03ad99d219 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -2486,6 +2486,9 @@ static void atmel_console_write(struct console *co, const char *s, u_int count)
pdc_tx = atmel_uart_readl(port, ATMEL_PDC_PTSR) & ATMEL_PDC_TXTEN;
atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS);

+ /* Make sure that tx path is actually able to send characters */
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN);
uart_console_write(port, s, count, atmel_console_putchar);

 \ /
  Last update: 2017-03-20 16:39    [W:0.031 / U:3.588 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site