[RFC 05/24] SERIAL: omap: no need to re-read EFR

Russell King rmk+kernel at arm.linux.org.uk
Sat Oct 6 08:40:42 EDT 2012

There's no need to re-read EFR after we've recently written it; the
register is a configuration register which doesn't change its value
without us writing to it.

Removing this re-reading avoids the possibility that we end up with
up->efr having the ECB bit set, which should only be temporarily set
when accessing the enhanced features.

Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
 drivers/tty/serial/omap-serial.c |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 391087e..654dd78 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -872,8 +872,6 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
 	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
-	up->efr = serial_in(up, UART_EFR);
 	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 	serial_out(up, UART_LCR, 0);

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