[PATCH v2 3/6] atmel_serial: Use existing console options only if BRG is running

From: Haavard Skinnemoen
Date: Wed Dec 19 2007 - 10:12:40 EST


If BRGR is zero, the baud rate generator isn't running, so the boot
loader can't have initialized the port.

Signed-off-by: Haavard Skinnemoen <hskinnemoen@xxxxxxxxx>
---
drivers/serial/atmel_serial.c | 15 +++++++--------
1 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/serial/atmel_serial.c b/drivers/serial/atmel_serial.c
index 61d71b0..a6b3828 100644
--- a/drivers/serial/atmel_serial.c
+++ b/drivers/serial/atmel_serial.c
@@ -842,13 +842,13 @@ static void __init atmel_console_get_options(struct uart_port *port, int *baud,
{
unsigned int mr, quot;

-// TODO: CR is a write-only register
-// unsigned int cr;
-//
-// cr = UART_GET_CR(port) & (ATMEL_US_RXEN | ATMEL_US_TXEN);
-// if (cr == (ATMEL_US_RXEN | ATMEL_US_TXEN)) {
-// /* ok, the port was enabled */
-// }
+ /*
+ * If the baud rate generator isn't running, the port wasn't
+ * initialized by the boot loader.
+ */
+ quot = UART_GET_BRGR(port);
+ if (!quot)
+ return;

mr = UART_GET_MR(port) & ATMEL_US_CHRL;
if (mr == ATMEL_US_CHRL_8)
@@ -868,7 +868,6 @@ static void __init atmel_console_get_options(struct uart_port *port, int *baud,
* lower than one of those, as it would make us fall through
* to a much lower baud rate than we really want.
*/
- quot = UART_GET_BRGR(port);
*baud = port->uartclk / (16 * (quot - 1));
}

--
1.5.3.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/