tty/serial: atmel: fix TX path in atmel_console_write()

A side effect of 89d8232 ("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 <[email protected]> Fixes: 89d8232 ("tty/serial: atmel_serial: BUG: stop DMA from transmitting in stop_tx") Cc: stable <[email protected]> #4.4+ Acked-by: Richard Genoud <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
OpenDingux · Mar 31, 2017 · 497e1e1 · 497e1e1
1 parent 31ca2c6
commit 497e1e1
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
@@ -2488,6 +2488,9 @@ 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);
 
 	/*