[PATCH 3.16 060/233] serial: efm32: Fix parity management in 'efm32_uart_console_get_options()'

From: Ben Hutchings
Date: Sat Sep 09 2017 - 19:34:18 EST


3.16.48-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>

commit be40597a1bc173bf9dadccdf5388b956f620ae8f upstream.

UARTn_FRAME_PARITY_ODD is 0x0300
UARTn_FRAME_PARITY_EVEN is 0x0200
So if the UART is configured for EVEN parity, it would be reported as ODD.
Fix it by correctly testing if the 2 bits are set.

Fixes: 3afbd89c9639 ("serial/efm32: add new driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Acked-by: Uwe Kleine-KÃnig <u.kleine-koenig@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/tty/serial/efm32-uart.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

--- a/drivers/tty/serial/efm32-uart.c
+++ b/drivers/tty/serial/efm32-uart.c
@@ -27,6 +27,7 @@
#define UARTn_FRAME 0x04
#define UARTn_FRAME_DATABITS__MASK 0x000f
#define UARTn_FRAME_DATABITS(n) ((n) - 3)
+#define UARTn_FRAME_PARITY__MASK 0x0300
#define UARTn_FRAME_PARITY_NONE 0x0000
#define UARTn_FRAME_PARITY_EVEN 0x0200
#define UARTn_FRAME_PARITY_ODD 0x0300
@@ -578,12 +579,16 @@ static void efm32_uart_console_get_optio
16 * (4 + (clkdiv >> 6)));

frame = efm32_uart_read32(efm_port, UARTn_FRAME);
- if (frame & UARTn_FRAME_PARITY_ODD)
+ switch (frame & UARTn_FRAME_PARITY__MASK) {
+ case UARTn_FRAME_PARITY_ODD:
*parity = 'o';
- else if (frame & UARTn_FRAME_PARITY_EVEN)
+ break;
+ case UARTn_FRAME_PARITY_EVEN:
*parity = 'e';
- else
+ break;
+ default:
*parity = 'n';
+ }

*bits = (frame & UARTn_FRAME_DATABITS__MASK) -
UARTn_FRAME_DATABITS(4) + 4;