From 829dd8112274d46c5ed82d46be506762e2c8fcd8 Mon Sep 17 00:00:00 2001 From: Haavard Skinnemoen Date: Fri, 8 Feb 2008 04:21:02 -0800 Subject: [PATCH] atmel_serial: use cpu_relax() when busy-waiting Replace two instances of barrier() with cpu_relax() since that's the right thing to do when busy-waiting. This does not actually change anything since cpu_relax() is defined as barrier() on both ARM and AVR32. Signed-off-by: Haavard Skinnemoen Acked-by: Andrew Victor Tested-by: Marc Pignat Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/serial/atmel_serial.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/serial/atmel_serial.c b/drivers/serial/atmel_serial.c index bb9c3574caa9..4d1ccc2b762d 100644 --- a/drivers/serial/atmel_serial.c +++ b/drivers/serial/atmel_serial.c @@ -615,7 +615,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios, imr = UART_GET_IMR(port); UART_PUT_IDR(port, -1); while (!(UART_GET_CSR(port) & ATMEL_US_TXEMPTY)) - barrier(); + cpu_relax(); /* disable receiver and transmitter */ UART_PUT_CR(port, ATMEL_US_TXDIS | ATMEL_US_RXDIS); @@ -794,7 +794,7 @@ void __init atmel_register_uart_fns(struct atmel_port_fns *fns) static void atmel_console_putchar(struct uart_port *port, int ch) { while (!(UART_GET_CSR(port) & ATMEL_US_TXRDY)) - barrier(); + cpu_relax(); UART_PUT_CHAR(port, ch); } -- 2.20.1