tty: serial - fix tty back references in termios

One or two drivers go poking back into the tty from the termios setting
routine in unsafe ways. We don't need to pass the tty down because the
[ab]users are just using it to get at things they can get at anyway.

This leaves low_latency setting to sort out along with set_ldisc use.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/serial/21285.c

@@ -216,7 +216,7 @@ serial21285_set_termios(struct uart_port *port, struct ktermios *termios,
 			struct ktermios *old)
 {
 	unsigned long flags;
-	unsigned int baud, quot, h_lcr;
+	unsigned int baud, quot, h_lcr, b;
 
 	/*
 	 * We don't support modem control lines.
@@ -234,12 +234,8 @@ serial21285_set_termios(struct uart_port *port, struct ktermios *termios,
 	 */
 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16); 
 	quot = uart_get_divisor(port, baud);
-
-	if (port->state && port->state->port.tty) {
-		struct tty_struct *tty = port->state->port.tty;
-		unsigned int b = port->uartclk / (16 * quot);
-		tty_encode_baud_rate(tty, b, b);
-	}
+	b = port->uartclk / (16 * quot);
+	tty_termios_encode_baud_rate(termios, b, b);
 
 	switch (termios->c_cflag & CSIZE) {
 	case CS5:

drivers/serial/imx.c

@@ -909,13 +909,11 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios,
 	rational_best_approximation(16 * div * baud, sport->port.uartclk,
 		1 << 16, 1 << 16, &num, &denom);
 
-	if (port->state && port->state->port.tty) {
-		tdiv64 = sport->port.uartclk;
-		tdiv64 *= num;
-		do_div(tdiv64, denom * 16 * div);
-		tty_encode_baud_rate(sport->port.state->port.tty,
+	tdiv64 = sport->port.uartclk;
+	tdiv64 *= num;
+	do_div(tdiv64, denom * 16 * div);
+	tty_termios_encode_baud_rate(termios,
 				(speed_t)tdiv64, (speed_t)tdiv64);
-	}
 
 	num -= 1;
 	denom -= 1;

drivers/serial/ioc3_serial.c

@@ -954,12 +954,13 @@ ioc3_change_speed(struct uart_port *the_port,
 		  struct ktermios *new_termios, struct ktermios *old_termios)
 {
 	struct ioc3_port *port = get_ioc3_port(the_port);
-	unsigned int cflag;
+	unsigned int cflag, iflag;
 	int baud;
 	int new_parity = 0, new_parity_enable = 0, new_stop = 0, new_data = 8;
 	struct uart_state *state = the_port->state;
 
 	cflag = new_termios->c_cflag;
+	iflag = new_termios->c_iflag;
 
 	switch (cflag & CSIZE) {
 	case CS5:
@@ -1000,12 +1001,12 @@ ioc3_change_speed(struct uart_port *the_port,
 
 	state->port.tty->low_latency = 1;
 
-	if (I_IGNPAR(state->port.tty))
+	if (iflag & IGNPAR)
 		the_port->ignore_status_mask &= ~(N_PARITY_ERROR
 						  | N_FRAMING_ERROR);
-	if (I_IGNBRK(state->port.tty)) {
+	if (iflag & IGNBRK) {
 		the_port->ignore_status_mask &= ~N_BREAK;
-		if (I_IGNPAR(state->port.tty))
+		if (iflag & IGNPAR)
 			the_port->ignore_status_mask &= ~N_OVERRUN_ERROR;
 	}
 	if (!(cflag & CREAD)) {

drivers/serial/ioc4_serial.c

@@ -1685,11 +1685,12 @@ ioc4_change_speed(struct uart_port *the_port,
 {
 	struct ioc4_port *port = get_ioc4_port(the_port, 0);
 	int baud, bits;
-	unsigned cflag;
+	unsigned cflag, iflag;
 	int new_parity = 0, new_parity_enable = 0, new_stop = 0, new_data = 8;
 	struct uart_state *state = the_port->state;
 
 	cflag = new_termios->c_cflag;
+	iflag = new_termios->c_iflag;
 
 	switch (cflag & CSIZE) {
 	case CS5:
@@ -1741,12 +1742,12 @@ ioc4_change_speed(struct uart_port *the_port,
 
 	state->port.tty->low_latency = 1;
 
-	if (I_IGNPAR(state->port.tty))
+	if (iflag & IGNPAR)
 		the_port->ignore_status_mask &= ~(N_PARITY_ERROR
 						| N_FRAMING_ERROR);
-	if (I_IGNBRK(state->port.tty)) {
+	if (iflag & IGNBRK) {
 		the_port->ignore_status_mask &= ~N_BREAK;
-		if (I_IGNPAR(state->port.tty))
+		if (iflag & IGNPAR)
 			the_port->ignore_status_mask &= ~N_OVERRUN_ERROR;
 	}
 	if (!(cflag & CREAD)) {

drivers/serial/max3100.c

@@ -430,17 +430,14 @@ max3100_set_termios(struct uart_port *port, struct ktermios *termios,
 	int baud = 0;
 	unsigned cflag;
 	u32 param_new, param_mask, parity = 0;
-	struct tty_struct *tty = s->port.state->port.tty;
 
 	dev_dbg(&s->spi->dev, "%s\n", __func__);
-	if (!tty)
-		return;
 
 	cflag = termios->c_cflag;
 	param_new = 0;
 	param_mask = 0;
 
-	baud = tty_get_baud_rate(tty);
+	baud = tty_termios_baud_rate(termios);
 	param_new = s->conf & MAX3100_BAUD;
 	switch (baud) {
 	case 300:
@@ -485,7 +482,7 @@ max3100_set_termios(struct uart_port *port, struct ktermios *termios,
 	default:
 		baud = s->baud;
 	}
-	tty_encode_baud_rate(tty, baud, baud);
+	tty_termios_encode_baud_rate(termios, baud, baud);
 	s->baud = baud;
 	param_mask |= MAX3100_BAUD;