From e1c609efbc0333840f2af2d875ca52ed8ee18587 Mon Sep 17 00:00:00 2001 From: Haavard Skinnemoen Date: Fri, 14 Mar 2008 14:54:13 +0100 Subject: [PATCH] atmel_serial: Drain console TX shifter before suspending Funny things may happen if we stop the USART clock before the shifter is empty. Prevent this from happening by waiting until the shifter is completely drained before allowing suspend to continue. Signed-off-by: Haavard Skinnemoen Cc: Andrew Victor --- drivers/serial/atmel_serial.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/serial/atmel_serial.c b/drivers/serial/atmel_serial.c index 5f0414f..6aeef22b 100644 --- a/drivers/serial/atmel_serial.c +++ b/drivers/serial/atmel_serial.c @@ -1454,6 +1454,12 @@ static int atmel_serial_suspend(struct platform_device *pdev, struct uart_port *port = platform_get_drvdata(pdev); struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + if (atmel_is_console_port(port) && console_suspend_enabled) { + /* Drain the TX shifter */ + while (!(UART_GET_CSR(port) & ATMEL_US_TXEMPTY)) + cpu_relax(); + } + if (device_may_wakeup(&pdev->dev) && !atmel_serial_clk_will_stop()) enable_irq_wake(port->irq); -- 2.7.4