tty/serial_core: Introduce lock mechanism for RS485
Introduce an homogeneous lock system between setting and using the rs485
data of the uart_port.
This patch should not be split into multiple ones in order to avoid
leaving the tree in an unstable state.
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Suggested-by: Alan Cox <alan@linux.intel.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/mcf.c b/drivers/tty/serial/mcf.c
index d7be1f1..fdd5c7b 100644
--- a/drivers/tty/serial/mcf.c
+++ b/drivers/tty/serial/mcf.c
@@ -257,12 +257,12 @@
mr2 |= MCFUART_MR2_TXCTS;
}
+ spin_lock_irqsave(&port->lock, flags);
if (port->rs485.flags & SER_RS485_ENABLED) {
dev_dbg(port->dev, "Setting UART to RS485\n");
mr2 |= MCFUART_MR2_TXRTS;
}
- spin_lock_irqsave(&port->lock, flags);
uart_update_timeout(port, termios->c_cflag, baud);
writeb(MCFUART_UCR_CMDRESETRX, port->membase + MCFUART_UCR);
writeb(MCFUART_UCR_CMDRESETTX, port->membase + MCFUART_UCR);
@@ -442,10 +442,8 @@
static int mcf_config_rs485(struct uart_port *port, struct serial_rs485 *rs485)
{
struct mcf_uart *pp = container_of(port, struct mcf_uart, port);
- unsigned long flags;
unsigned char mr1, mr2;
- spin_lock_irqsave(&port->lock, flags);
/* Get mode registers */
mr1 = readb(port->membase + MCFUART_UMR);
mr2 = readb(port->membase + MCFUART_UMR);
@@ -460,7 +458,6 @@
writeb(mr1, port->membase + MCFUART_UMR);
writeb(mr2, port->membase + MCFUART_UMR);
port->rs485 = *rs485;
- spin_unlock_irqrestore(&port->lock, flags);
return 0;
}